武田 朋也 (タケダ トモヤ)

  • 薬学部 医療薬学科 講師
Last Updated :2024/02/02

コミュニケーション情報 byコメンテータガイド

  • コメント

    がん治療に関する研究を行っております。がんのメカニズムを解明し、がんに特有な変異やシグナル伝達系を標的とした新たな治療法の開発に取り組んでいます。

研究者情報

学位

  • 修士(神戸大学)
  • 博士(近畿大学)

ホームページURL

J-Global ID

研究キーワード

  • がん転移   分子標的薬耐性   薬物治療学   

現在の研究分野(キーワード)

    がん治療に関する研究を行っております。がんのメカニズムを解明し、がんに特有な変異やシグナル伝達系を標的とした新たな治療法の開発に取り組んでいます。

研究分野

  • ライフサイエンス / 腫瘍生物学

経歴

  • 2023年04月 - 現在  近畿大学 薬学部 講師
  • 2018年04月 - 2023年03月  近畿大学薬学部助教
  • 2014年04月 - 2018年03月  近畿大学薬学部助手

学歴

  • 2009年04月 - 2011年03月   神戸大学   大学院医学研究科

所属学協会

  • 日本薬学会   日本がん分子標的治療学会   日本癌学会   

研究活動情報

論文

  • Tomoya Takeda; Masanobu Tsubaki; Shuji Genno; Kenta Tokunaga; Remi Tanaka; Shozo Nishida
    International journal of molecular medicine 52 3 2023年09月 
    Triple‑negative breast cancer (TNBC), a highly metastatic subtype of breast cancer, and it has the worst prognosis among all subtypes of breast cancer. However, no effective systematic therapy is currently available for TNBC metastasis. Therefore, novel therapies targeting the key molecular mechanisms involved in TNBC metastasis are required. The present study examined whether the expression levels of human epidermal growth factor receptor 3 (HER3) were associated with the metastatic phenotype of TNBC, and evaluated the potential of HER3 as a therapeutic target in vitro and in vivo. A new highly metastatic 4T1 TNBC cell line, termed 4T1‑L8, was established. The protein expression levels in 4T1‑L8 cells were measured using luminex magnetic bead assays and western blot analysis. The HER3 expression levels and distant metastasis‑free survival (DMFS) in TNBC were analyzed using Kaplan‑Meier Plotter. Transwell migration and invasion assays were performed to detect migration and invasion. The anti‑metastatic effects were determined in an experimental mouse model of metastasis. The results revealed that the increased expression of the HER3/Akt/mTOR pathway was associated with a greater level of cell migration, invasion and metastasis of TNBC cells. In addition, it was found that high expression levels of HER3 were associated with a poor DMFS. The inhibition of the HER3/Akt/mammalian target of rapamycin (mTOR) pathway decreased the migration, invasion and metastasis of TNBC cells by decreasing the expression of C‑X‑C chemokine receptor type 4 (CXCR4). Furthermore, treatment of metastatic TNBC cells with everolimus inhibited their migration, invasion and metastasis by decreasing CXCR4 expression. Thus, targeting the HER3/Akt/mTOR pathway opens up a new avenue for the development of therapeutics against TNBC metastasis; in addition, everolimus may prove to be an effective therapeutic agent for the suppression of TNBC metastasis.
  • Masanobu Tsubaki; Tomoya Takeda; Takuya Matsuda; Kana Kishimoto; Honoka Takefuji; Yuzuki Taniwaki; Misa Ueda; Tadafumi Hoshida; Kazufumi Tanabe; Shozo Nishida
    Cancer cell international 23 1 73 - 73 2023年04月 
    BACKGROUND: KRAS mutations are fraught with the progression of colorectal cancer and resistance to chemotherapy. There are pathways such as extracellular regulated protein kinase 1/2 (ERK1/2) and Akt downstream and farnesylation and geranylgeranylation upstream that are activated upon mutated KRAS. Previous studies have shown that statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are effective to treat KRAS mutated colorectal cancer cells. Increased doses of oxaliplatin (L-OHP), a well-known alkylating chemotherapeutic drug, causes side effects such as peripheral neuropathy due to ERK1/2 activation in spinal cords. Hence, we examined the combinatorial therapeutic efficacy of statins and L-OHP to reduce colorectal cancer cell growth and abrogate neuropathy in mice. METHODS: Cell survival and confirmed apoptosis was assessed using WST-8 assay and Annexin V detection kit. Detection of phosphorylated and total proteins was analyzed the western blotting. Combined effect of simvastatin and L-OHP was examined the allograft mouse model and L-OHP-induced neuropathy was assessed using cold plate and von Frey filament test. RESULTS: In this study, we examined the effect of combining statins with L-OHP on induction of cell death in colorectal cancer cell lines and improvement of L-OHP-induced neuropathy in vivo. We demonstrated that combined administration with statins and L-OHP significantly induced apoptosis and elevated the sensitivity of KRAS-mutated colorectal cancer cells to L-OHP. In addition, simvastatin suppressed KRAS prenylation, thereby enhancing antitumor effect of L-OHP through downregulation of survivin, XIAP, Bcl-xL, and Bcl-2, and upregulation of p53 and PUMA via inhibition of nuclear factor of κB (NF-κB) and Akt activation, and induction of c-Jun N-terminal kinase (JNK) activation in KRAS-mutated colorectal cancer cells. Moreover, simvastatin enhanced the antitumor effects of L-OHP and suppressed L-OHP-induced neuropathy via ERK1/2 activation in vivo. CONCLUSION: Therefore, statins may be therapeutically useful as adjuvants to L-OHP in KRAS-mutated colorectal cancer and may also be useful in the treatment of L-OHP-induced neuropathy.
  • Masanobu Tsubaki; Tomoya Takeda; Yuuichi Koumoto; Takehiro Usami; Takuya Matsuda; Shiori Seki; Kazuko Sakai; Kazuto Nishio; Shozo Nishida
    Cell proliferation 56 6 e13420  2023年02月 
    The development of BCR::ABL1 tyrosine kinase inhibitors (TKIs), such as dasatinib, has dramatically improved survival in cases of chronic myeloid leukaemia (CML). However, the development of resistance to BCR::ABL1 TKIs is a clinical problem. BCR::ABL1 TKI resistance is known to have BCR::ABL1-dependent or BCR::ABL1-independent mechanisms, but the mechanism of BCR::ABL1 independence is not well understood. In the present study, we investigated the mechanism of BCR::ABL1-independent dasatinib resistance. The expression and activation level of genes or proteins were evaluated using array CGH, real time PCR, or western blot analysis. Gene expression was modulated using siRNA-mediated knockdown. Cell survival was assessed by using trypan blue dye method. We found that dasatinib-resistant K562/DR and KU812/DR cells did not harbour a BCR::ABL1 mutation but had elevated expression and/or activation of MOS, TPL2 and ERK1/2. In addition, MOS siRNA, TPL2 siRNA and trametinib resensitized dasatinib-resistant cells to dasatinib. Moreover, expression levels of MOS in dasatinib non-responder patients with CML were higher than those in dasatinib responders, and the expression of TPL2 tended to increase in dasatinib non-responder patients compared with that in responder patients. Our results indicate that activation of ERK1/2 by elevated MOS and TPL2 expression is involved in dasatinib resistance, and inhibition of these proteins overcomes dasatinib resistance. Therefore, MOS, TPL2 and ERK1/2 inhibitors may be therapeutically useful for treating BCR::ABL1-independent dasatinib-resistant CML.
  • Masanobu Tsubaki; Tomoya Takeda; Takuya Matsuda; Kana Kishimoto; Remi Tanaka; Katsumasa Tsurushima; Toshihiko Ishizaka; Shozo Nishida
    Clinical and experimental medicine 2022年11月 
    Multiple myeloma (MM) frequently acquires multidrug resistance (MDR), which is due to poor prognosis. Our previous study indicated that high expression of Survivin and multidrug resistance protein 1 (MDR1) and decreased expression of Bim are associated with MDR in adriamycin- and dexamethasone-resistant cells. However, the fundamental mechanism of MDR in adriamycin- and dexamethasone-resistant MM cells is still unidentified. In this study, we examined the MDR mechanism in adriamycin- and dexamethasone-resistant cells. RPMI8226/ADM, ARH-77/ADM, RPMI8226/DEX, and ARH-77/DEX cells exhibited enhanced nuclear factor κB (NF-κB) p65, Akt, and extracellular signal-regulated kinase 1/2 (ERK1/2) activation. Combination treatment with NF-κB p65, phosphoinositide 3-kinase (PI3K), and mitogen-activated protein kinase 1/2 (MEK1/2) inhibitors resensitized to adriamycin and dexamethasone via increased Bim expression. Although treatment with MDR1 or Survivin siRNA did not overcome adriamycin and dexamethasone resistance in RPMI8226/ADM and RPMI8226/DEX cells, administration of Bim siRNA induced adriamycin and dexamethasone resistance in RPMI8226 cells. Moreover, low expression of Bim was related to poor prognosis in MM patients. These results indicate that activation of NF-κB p65, Akt, and ERK1/2 is associated with adriamycin and dexamethasone resistance via decreasing Bim expression, and these signal inhibitor combinations overcome drug resistance in MM. These findings suggest that combination treatment with these inhibitors and adriamycin or dexamethasone may be a promising therapy for adriamycin- and dexamethasone-resistant MM.
  • Masanobu Tsubaki; Tomoya Takeda; Takuya Matsuda; Akihiro Kimura; Remi Tanaka; Sakiko Nagayoshi; Tadafumi Hoshida; Kazufumi Tanabe; Shozo Nishida
    BMB reports 56 2 78 - 83 2022年10月 
    Chronic myeloid leukemia (CML) has a markedly improved prognosis with the use of breakpoint cluster region-abelson 1 (BCR-ABL1) tyrosine kinase inhibitors (BCR-ABL1 TKIs). However, approximately 40% of patients are resistant or intolerant to BCR-ABL1 TKIs. Hypoxia inducible factor 1α (HIF-1α) is a hypoxia response factor that has been reported to be highly expressed in CML patients, making it a candidate target molecule for the therapy of CML as well as BCR-ABL1 TKI-resistant CML. In this study, we examined whether HIF-1α inhibitors induce cell death in CML cells and BCR-ABL1 TKI-resistant CML cells. We found that echinomycin and PX-478 induced cell death in BCR-ABL1 TKIs sensitive and resistant CML cells at similar concentrations while the cell sensitivity was not affected with imatinib or dasatinib in BCR-ABL1 TKIs resistant CML cells. In addition, echinomycin and PX-478 inhibited the c-Jun N-terminal kinase (JNK), Akt, and extracellular-regulated protein kinase 1/2 (ERK1/2) activation via suppression of BCR-ABL1 and Met expression in BCR-ABL1 sensitive and resistant CML cells. Moreover, treatment with HIF-1α siRNA induced cell death by inhibiting BCR-ABL1 and Met expression and activation of JNK, Akt, and ERK1/2 in BCR-ABL1 TKIs sensitive and resistant CML cells. These results indicated that HIF-1α regulates BCR-ABL and Met expression and is involved in cell survival in CML cells, suggesting that HIF-1α inhibitors induce cell death in BCR-ABL1 TKIs sensitive and resistant CML cells. These findings suggest that HIF-1α inhibitors may be beneficial as treatment for CML.
  • Katsumasa Tsurushima; Masanobu Tsubaki; Tomoya Takeda; Takuya Matsuda; Akihiro Kimura; Honoka Takefuji; Akane Okada; Chiaki Sakamoto; Toshihiko Ishizaka; Shozo Nishida
    International journal of molecular sciences 23 15 2022年08月 
    Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.
  • Tomoya Takeda; Masanobu Tsubaki; Takuya Matsuda; Akihiro Kimura; Minami Jinushi; Teruki Obana; Manabu Takegami; Shozo Nishida
    Oncology reports 47 6 2022年06月 
    Tamoxifen resistance remains a major obstacle in the treatment of estrogen receptor (ER)‑positive breast cancer. In recent years, the crucial role of the epithelial‑mesenchymal transition (EMT) process in the development of drug resistance in breast cancer has been underlined. However, the central molecules inducing the EMT process during the development of tamoxifen resistance remain to be elucidated. In the present study, it was demonstrated that tamoxifen‑resistant breast cancer cells underwent EMT and exhibited an enhanced cell motility and invasive behavior. The inhibition of snail family transcriptional repressor 1 (Snail) and twist family BHLH transcription factor 1 (Twist) reversed the EMT phenotype and decreased the tamoxifen resistance, migration and invasion of tamoxifen‑resistant breast cancer cells. In addition, it was observed that the inhibition of epidermal growth factor receptor (EGFR) reversed the EMT phenotype in tamoxifen‑resistant MCF7 (MCF‑7/TR) cells via the downregulation of Snail and Twist. Notably, the EGFR inhibitor, gefitinib, decreased tamoxifen resistance, migration and invasion through the inhibition of Snail and Twist. On the whole, the results of the present study suggest that EGFR may be a promising therapeutic target for tamoxifen‑resistant breast cancer. Moreover, it was suggested that gefitinib may serve as a potent novel therapeutic strategy for breast cancer patients, who have developed tamoxifen resistance.
  • Katsumasa Tsurushima; Yukiko Yanagishita; Naoki Ogawa; Chika Fujii; Yukako Yasui; Tomoya Takeda; Masanobu Tsubaki; Shozo Nishida; Toshihiko Ishizaka; Jun Yamamura; Syunji Kamigaki
    Gan to kagaku ryoho. Cancer & chemotherapy 49 6 701 - 704 2022年06月 
    Olanzapine(OLZ)is a multi-acting receptor-targeted antipsychotic drug approved in Japan in December 2017 for the treatment of anticancer drug-induced nausea and vomiting. However, the recommended doses and administration periods of OLZ in the literature and guidelines are varied. Reports on the efficacy and safety of OLZ combined with perioperative chemotherapy for breast cancer in Japanese patients are few. Moreover, the risk of nausea and vomiting during treatment with anticancer drugs in young and women patients remains to be high. In this study, we conducted an exploratory survey on the optimal duration of OLZ administration(days 1-4: 5 mg, before sleep)during perioperative breast cancer 5-fluorouracil, epirubicin, cyclophosphamide(FEC)therapy. We found that treatment with OLZ showed efficacy in improving nausea grade and maintaining relative dose intensity. Moreover, it could be used safely without interruption due to side effects, such as weight gain, elevation in blood glucose, somnolence, and insomnia. Prophylactic antiemetic therapy with OLZ administration (days 1-4: 5 mg)prior to sleep was effective in patients having FEC therapy-induced nausea and vomiting.
  • Tomoya Takeda; Yuuta Yamamoto; Masanobu Tsubaki; Takuya Matsuda; Akihiro Kimura; Natsumi Shimo; Shozo Nishida
    Oncology letters 23 4 106 - 106 2022年04月 
    Colorectal cancer (CRC) is one of the most prevalent malignant diseases and metastasis is the leading cause of poor prognosis in patients with CRC. Further knowledge of the molecular mechanism underlying metastasis in CRC and the identification of new therapeutic targets are needed. Yes-associated protein (YAP) is a transcriptional regulator that is important in tumorigenesis and tumor cell proliferation. The present study investigated whether YAP was crucial for CRC migration and invasion. The protein expression levels were detected via western blotting, and migration and invasion were analyzed by Transwell migration and invasion assays. Subsequently, YAP expression was silenced using small interfering RNA. The mRNA expression levels were detected via reverse transcription-quantitative PCR and cell viability was assessed via Trypan blue exclusion assay. The results revealed that YAP protein levels were associated with migration and invasion of CRC cells. Notably, YAP small interfering RNA inhibited the migration and invasion of DLD-1 cells. In addition, the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway inhibitor LY294002 suppressed the migration and invasion of DLD-1 cells by decreasing the expression of YAP. Notably, the present study demonstrated that verteporfin mediated the suppression of migration and invasion of DLD-1 cells due to the decreased expression of YAP. Therefore, targeting YAP may be valuable for developing therapeutic strategies against CRC, and verteporfin may be an effective therapy to suppress the migration and invasion of CRC.
  • M Tsubaki; T Takeda; T Mastuda; A Kimura; M Yanae; A Maeda; T Hoshida; K Tanabe; S Nishida
    Journal of physiology and pharmacology : an official journal of the Polish Physiological Society 73 1 2022年02月 
    Statins and fibrates are frequently used to treat hyperlipidemia; however, these drugs may have adverse effects such as rhabdomyolysis. The incidence of rhabdomyolysis due to fibrates and statins is low (0.0028-0.0096%) when administered as monotherapy, however it increases to 0.015-0.021% when the drugs are used in combination. The mechanism underlying myotoxicity induced by the combination of statins and fibrates is yet unclear. Here, we investigated the mechanisms underlying induced myotoxicity in rat myoblasts L6 and differentiated L6 cells (myotubes) using a combination of statins and fibrates. We found that cell death induced by a combination of fluvastatin or simvastatin with bezafibrate or fenofibrate in L6 myoblasts and myotubes was mediated by inhibition of geranylgeranyl pyrophosphate (GGPP) production. Additionally, the drug combination inhibited Rho activation in L6 myoblasts and myotube cells. In L6 myoblasts, the combination of statins and bezafibrate enhanced p27 expression and induced G1 arrest and apoptosis. Furthermore, combined treatment suppressed Akt activation and enhanced Bim expression in L6 myotubes but did not affect extracellular regulated protein kinase 1/2 activation. These results suggested that combined administration of statins and fibrates induced death of L6 myoblasts and myotube cells by inhibiting GGPP biosynthesis and Rho pathway activation. Supplementation with GGPP may be therapeutically beneficial for preventing myotoxicity associated with combined statin and fibrates treatment.
  • Tomoya Takeda; Masanobu Tsubaki; Natsuki Kato; Shuji Genno; Eri Ichimura; Aya Enomoto; Motohiro Imano; Takao Satou; Shozo Nishida
    Oncology letters 22 6 827 - 827 2021年12月 
    Melanomas are highly malignant tumors that readily metastasize and have poor prognosis. Targeted therapy is a cornerstone of treatment for patients with melanoma. Although c-Kit gene aberration has found in 5-10% of melanoma cases, research on c-Kit inhibitors for melanoma with c-Kit aberration have been disappointing. Sorafenib is a tyrosine kinase inhibitor, whose targets include c-Kit, platelet derived growth factor receptor (PDGFR), VEGFR and RAF. The present study aimed to examine the effect of sorafenib on metastatic melanoma with c-Kit aberration. Cell viability was assessed via trypan blue assay. Migration and invasion were analyzed using cell culture inserts. The anti-metastatic effects and antitumour activity of sorafenib were determined in an in vivo model. Protein expression was detected via western blotting, and the expression of MMP and very late antigen (VLA) was detected via reverse transcription-quantitative PCR. It was identified that sorafenib decreased cell viability, migration and invasion in vitro. Furthermore, sorafenib inhibited metastasis and tumor growth in vivo. Mechanistically, sorafenib inhibited c-Kit, PDGFR, VEGFR, B-Raf and c-Raf phosphorylation both in vitro and in vivo. In addition, sorafenib reduced the expression levels of MMPs and VLA. Importantly, there was a significant effect of sorafenib treatment on overall survival in mice. Collectively, this study suggests that sorafenib may serve as a novel therapeutic option for melanoma with c-Kit dysregulation.
  • Daichiro Fujiwara; Masanobu Tsubaki; Tomoya Takeda; Makoto Miura; Shozo Nishida; Katsuhiko Sakaguchi
    European journal of hospital pharmacy : science and practice 28 5 266 - 270 2021年09月 
    OBJECTIVES: The incidence of severe mucosal damage due to low nutritional status is high in patients receiving concurrent chemoradiotherapy (CCRT) for head and neck cancer. Objective assessments do not exist for discharge criteria after completion of CCRT. Although the prognostic nutritional index (PNI) is an objective indicator of postoperative outcomes in patients undergoing cancer surgery, the prognostic impact of the PNI in patients with head and neck cancer receiving CCRT is unexplored. We investigated whether the PNI could be an objective criterion for nutritional status and a discharge criterion after completion of CCRT. METHODS: We assessed the medical records of 23 patients with head and neck cancer who received triweekly cisplatin +radiotherapy (2 Gy ×35 fractions). We evaluated whether the PNI could be a useful evaluation indicator in patients with head and neck cancer receiving CCRT and determined the cut-off PNI value by receiver operating characteristic (ROC) curve analysis as a criterion for hospital discharge. RESULTS: The PNI pre-treatment and post-treatment values were 51.0 and 38.0, respectively (p<0.05). The median length of hospitalisation after therapy was 5 days in patients with grades 1 and 2 and 10 days in patients with grade 3 oral and pharyngeal mucositis (p<0.05). The optimal cut-off PNI value as a criterion for hospital discharge was found to be 40.4 (grades 1 and 2 mucositis) and 38.6 (grade 3 mucositis) by the ROC analysis. CONCLUSIONS: The PNI is a simple, objective and temporal indicator which is useful in assessing the nutritional status of patients with head and neck cancer. The PNI could be used as an objective indicator to determine the time of discharge after CCRT completion.
  • Masanobu Tsubaki; Tomoya Takeda; Takuya Matsuda; Yuuta Yamamoto; Aki Higashinaka; Kasane Yamamoto; Katsumasa Tsurushima; Toshihiko Ishizaka; Shozo Nishida
    Cytokine 144 155591 - 155591 2021年08月 
    Interleukin 19 (IL-19) is a member of the IL-10 family of cytokines and is known as an inhibitory cytokine. IL-10, also an inhibitory cytokine, suppresses the receptor activator of nuclear factor κB (NF-κB) ligand (RANKL)-induced osteoclast differentiation. However, the effects of IL-19 on osteoclast differentiation are not currently well-understood. In this study, we examined whether IL-19 suppresses osteoclast differentiation in the mouse macrophage-like cell line RAW264.7. We found that IL-19 inhibited RANKL-induced osteoclast differentiation. In addition, IL-19 suppressed RANKL-induced NF-κB and p38 mitogen-activated protein kinase (p38MAPK) activation and c-Fos expression. Moreover, RANKL inhibited IL-19 mRNA expression and secretion in RAW264.7 cells, and the inhibition of the IL-19 function promoted osteoclast differentiation. These results indicate that IL-19 suppressed osteoclast differentiation via the inhibition of NF-κB and p38MAPK activation and c-Fos expression. Furthermore, IL-19 may maintain the osteoclast precursor state, such as monocytes and macrophages. These findings may be useful in the development of osteoclast inhibitors, thereby improving treatments for osteoclast activation-related diseases, such as osteoporosis.
  • Tomoya Takeda; Masanobu Tsubaki; Shuji Genno; Takuya Matsuda; Yuuta Yamamoto; Akihiro Kimura; Nao Shimizu; Shozo Nishida
    Clinical and experimental medicine 22 2 221 - 228 2021年07月 
    Non-small cell lung cancer (NSCLC) is a highly aggressive cancer with one of the most prevalent malignant tumors. Metastasis in NSCLC is the major cause of treatment failure and cancer-related deaths. Yes-associated protein (YAP) is a transcriptional coactivator regulated by the evolutionarily conserved Hippo signaling pathway that regulates organ size, growth, and regeneration. YAP is highly expressed in several malignant tumor types. Furthermore, YAP promotes tumor initiation and/or progression in various types of cancer. However, it is unclear whether YAP contributes to the metastasis in NSCLC and serves as a useful therapeutic target. Here, we investigated whether levels of YAP correlate with metastatic phenotype in NSCLC cells and serve as a useful therapeutic target. We found that high levels of YAP associate with high cell migration, invasion, and metastasis in NSCLC cell lines. Furthermore, YAP siRNA decreased the migration and invasion in NSCLC cells. Additionally, verteporfin, an agent used for the treatment of symptomatic polypoidal choroidal vasculopathy, decreased the expression of YAP and inhibited migration, invasion, and metastasis in NSCLC cells. Thus, the study suggests that targeting YAP may present a new avenue to develop therapeutics against metastasis in NSCLC and that verteporfin has potential molecular therapeutic strategy for the treatment of metastatic NSCLC.
  • Yusuke Morii; Masanobu Tsubaki; Tomoya Takeda; Rie Otubo; Shiori Seki; Yuta Yamatomo; Motohiro Imano; Takao Satou; Kazunori Shimomura; Shozo Nishida
    European journal of pharmacology 898 173957 - 173957 2021年05月 
    Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutation in colon cancer contributes to the poor prognosis of the disease and chemoresistance of tumors. New therapies are needed; however, the lack of knowledge of the mechanism of chemoresistance has hindered progress. In this study, we investigated the mechanism of the reduced sensitivity of colon cancer cells to 5-fluorouracil (5-FU) and oxaliplatin (L-OHP), and the effects of perifosine, an Akt inhibitor that enhances the cytotoxicity of 5-FU and L-OHP in colon cancer cells harboring the PIK3CA mutation. The use of 5-FU or L-OHP alone or in combination induced significant death of Caco-2 cells (PIK3CA wild type), but only weakly decreased the viability of DLD-1 and SW948 cells harboring the PIK3CA mutation. The use of 5-FU and L-OHP, either alone or in combination, strongly suppressed Akt activation, Survivin, Bcl-2, and Bcl-xL expression, and enhanced Puma, phospho-p53, and p53 expression in Caco-2 cells than in DLD-1 cells. In addition, perifosine enhanced the cytotoxicity of the 5-FU and L-OHP combination, inhibited Akt activation and the expression of Survivin, Bcl-2, and Bcl-xL, and increased the expression of Puma, phospho-p53, and p53 in DLD-1 cells. These results indicate that PIK3CA mutation contributes to reduced sensitivity to 5-FU and L-OHP via Akt activation in colon cancer cells. Perifosine increases the efficacy of 5-FU and L-OHP by suppressing Akt activation. Thus, the use of an Akt inhibitor in combination with 5-FU and L-OHP may be beneficial in colon cancer with cells harboring the PIK3CA mutation.
  • Masanobu Tsubaki; Tomoya Takeda; Takuya Matsuda; Shiori Seki; Yoshika Tomonari; Shoutaro Koizumi; Miki Nagatakiya; Mai Katsuyama; Yuuta Yamamoto; Katsumasa Tsurushima; Toshihiko Ishizaka; Shozo Nishida
    Biomedicines 9 1 2021年01月 
    Multiple myeloma (MM) is an incurable malignancy often associated with primary and acquired resistance to therapeutic agents, such as proteasome inhibitors. However, the mechanisms underlying the proteasome inhibitor resistance are poorly understood. Here, we elucidate the mechanism of primary resistance to bortezomib and ixazomib in the MM cell lines, KMS-20, KMS-26, and KMS-28BM. We find that low bortezomib and ixazomib concentrations induce cell death in KMS-26 and KMS-28BM cells. However, high bortezomib and ixazomib concentrations induce cell death only in KMS-20 cells. During Gene Expression Omnibus analysis, KMS-20 cells exhibit high levels of expression of various genes, including anti-phospho-fibroblast growth factor receptor 1 (FGFR1), chemokine receptor type (CCR2), and serum and glucocorticoid regulated kinase (SGK)1. The SGK1 inhibitor enhances the cytotoxic effects of bortezomib and ixazomib; however, FGFR1 and CCR2 inhibitors do not show such effect in KMS-20 cells. Moreover, SGK1 activation induces the phosphorylation of NF-κB p65, and an NF-κB inhibitor enhances the sensitivity of KMS-20 cells to bortezomib and ixazomib. Additionally, high levels of expression of SGK1 and NF-κB p65 is associated with a low sensitivity to bortezomib and a poor prognosis in MM patients. These results indicate that the activation of the SGK1/NF-κB pathway correlates with a low sensitivity to bortezomib and ixazomib, and a combination of bortezomib and ixazomib with an SGK1 or NF-κB inhibitor may be involved in the treatment of MM via activation of the SGK1/NF-κB pathway.
  • Masanobu Tsubaki; Shuuji Genno; Tomoya Takeda; Takuya Matsuda; Naoto Kimura; Yuuma Yamashita; Yuusuke Morii; Kazunori Shimomura; Shozo Nishida
    Biomedicines 9 1 2021年01月 
    The high mortality rate of cancer is strongly correlated with the development of distant metastases at secondary sites. Although Rho GTPases, such as RhoA, RhoB, RhoC, and RhoE, promote tumor metastasis, the main roles of Rho GTPases remain unidentified. It is also unclear whether rhosin, a Rho inhibitor, acts by suppressing metastasis by a downstream inhibition of Rho. In this study, we investigated this mechanism of metastasis in highly metastatic melanoma and breast cancer cells, and the mechanism of inhibition of metastasis by rhosin. We found that rhosin suppressed the RhoA and RhoC activation, the nuclear localization of YAP, but did not affect ERK1/2, Akt, or NF-κB activation in the highly metastatic cell lines B16BL6 and 4T1. High expression of YAP was associated with poor overall and recurrence-free survival in patients with breast cancer or melanoma. Treatment with rhosin inhibited lung metastasis in vivo. Moreover, rhosin inhibited tumor cell adhesion to the extracellular matrix via suppression of RHAMM expression, and inhibited SDF-1-induced cell migration and invasion by decreasing CXCR4 expression in B16BL6 and 4T1 cells. These results suggest that the inhibition of RhoA/C-YAP pathway by rhosin could be an extremely useful therapeutic approach in patients with melanoma and breast cancer.
  • Keisuke Tateishi; Masanobu Tsubaki; Tomoya Takeda; Yuuta Yamatomo; Motohiro Imano; Takao Satou; Shozo Nishida
    Journal of B.U.ON. : official journal of the Balkan Union of Oncology 26 2 606 - 612 2021年 
    PURPOSE: Head and neck squamous cell carcinoma (HNSCC) is a major malignancy worldwide. Ras overexpression in HNSCC is known to promote tumor cell growth; therefore, inhibition of Ras activation could lead to tumor growth suppression in HNSCC patients. Here, we investigated the effect of FTI-277, a farnesyl transferase inhibitor, and GGTI-287, a geranyltransferase 1 inhibitor, on the Ras signaling pathway in HNSCC cell lines-HEp-2 and HSC-3. METHODS: Cell viability was analyzed using the trypan blue staining exclusion assay. The apoptosis of cells was assessed by flow cytometry and caspase activation analysis. The expression levels of proteins were examined using western blot analysis. RESULTS: FTI-277 and GGTI-287 induced cell death, enhanced caspase 3 activity, and increased the number of annexin V-positive cells in HEp-2 and HSC-3 cells. FTI-277 and GGTI-287 induced apoptosis in HSC-3 cells at much lower concentrations than that in HEp-2 cells. FTI-277 and GGTI-287 decreased the concentration of phosphorylated ERK1/2 and mTOR via membrane localization of Ras and enhanced Bim expression. Furthermore, FTI-277 and GGTI-287 induced cell death in v-H-Ras-transfected NIH3T3 (NW7) cells and not in empty vector-transfected NIH3T3 (NV20) cells. CONCLUSION: FTI-277 and GGTI-287 may be useful as potential therapeutic agents for treating HNSCC patients; moreover, farnesyl transferase and geranylgeranyltransferase 1 inhibitors can be further developed as anticancer agents.
  • Natsuki Kato; Keisuke Tateishi; Masanobu Tsubaki; Tomoya Takeda; Mikihiro Matsumoto; Katsumasa Tsurushima; Toshihiko Ishizaka; Shozo Nishida
    Pharmaceuticals (Basel, Switzerland) 14 1 2020年12月 
    Chemotherapy-induced peripheral neuropathy is a common factor in limiting therapy which can result in therapy cessation or dose reduction. Gabapentin, a calcium channel inhibitor, and duloxetine, a serotonin noradrenaline reuptake inhibitor, are used to treat a variety of pain conditions such as chronic low back pain, postherpetic neuralgia, and diabetic neuropathy. It has been reported that administration of gabapentin suppressed oxaliplatin- and paclitaxel-induced mechanical hyperalgesia in rats. Moreover, duloxetine has been shown to suppress oxaliplatin-induced cold allodynia in rats. However, the mechanisms by which these drugs prevent oxaliplatin- and paclitaxel-induced neuropathy remain unknown. Behavioral assays were performed using cold plate and the von Frey test. The expression levels of proteins were examined using western blot analysis. In this study, we investigated the mechanisms by which gabapentin and duloxetine prevent oxaliplatin- and paclitaxel-induced neuropathy in mice. We found that gabapentin and duloxetine prevented the development of oxaliplatin- and paclitaxel-induced cold and mechanical allodynia. In addition, our results revealed that gabapentin and duloxetine suppressed extracellular signal-regulated protein kinase 1/2 (ERK1/2) phosphorylation in the spinal cord of mice. Moreover, PD0325901 prevented the development of oxaliplatin- and paclitaxel-induced neuropathic-like pain behavior by inhibiting ERK1/2 activation in the spinal cord of mice. In summary, our findings suggest that gabapentin, duloxetine, and PD0325901 prevent the development of oxaliplatin- and paclitaxel-induced neuropathic-like pain behavior by inhibiting ERK1/2 phosphorylation in mice. Therefore, inhibiting ERK1/2 phosphorylation could be an effective preventive strategy against oxaliplatin- and paclitaxel-induced neuropathy.
  • Tomoya Takeda; Masanobu Tsubaki; Shuji Genno; Chisato Nemoto; Yasuka Onishi; Yuuta Yamamoto; Motohiro Imano; Takao Satou; Shozo Nishida
    Oncology reports 44 5 2211 - 2218 2020年11月 
    Imatinib is the gold standard in the conventional treatment of chronic myeloid leukemia (CML). However, some patients become resistant to imatinib therapy. To overcome this resistance, second‑generation (dasatinib, nilotinib, and bosutinib) and third‑generation (ponatinib) tyrosine kinase inhibitors (TKIs) have been developed and have been shown to be effective against refractory CML. Although these TKIs provide many benefits for patients with CML, advanced patients show resistance even to these TKIs. Therefore, novel therapeutic strategies are urgently needed for the treatment of TKI‑resistant CML patients. AT9283 is a multi‑targeted kinase inhibitor with potent activity against Janus kinase (JAK), Aurora kinases, and Abl. In the present study, we showed that AT9283 significantly decreased the cell viability of both TKI‑sensitive and TKI‑resistant CML cells as determined by trypan blue exclusion assay. In addition, cell cycle analysis, Annexin V assay, and caspase‑3/7 activity assay revealed that AT9283 increased the cell population in the G2/M phase and induced apoptosis. We investigated the molecular mechanisms underlying the decrease in cell viability upon treatment with AT9283 by western blotting. Interestingly, our results showed that AT9283 inhibited the expression of Aurora A, Aurora B, and downstream Histone H3 phosphorylation. In contrast, we observed no changes in the levels of Bcr‑Abl, signal transducer and activator of transcription 3 (STAT3), extracellular signal‑regulated kinase (ERK), and Akt phosphorylation. In addition, we found that AMG900, a selective Aurora A and Aurora B inhibitor, increased the G2/M phase cell population and induced apoptosis via inhibition of Aurora A and Aurora B in both TKI‑sensitive and TKI‑resistant CML cells. Our studies show that Aurora A and Aurora B are promising therapeutic targets for TKI‑sensitive and TKI‑resistant CML, and AT9283 may have potential clinical applications for the treatment of TKI‑resistant CML patients.
  • Masanobu Tsubaki; Shiori Seki; Tomoya Takeda; Akiko Chihara; Yuuko Arai; Yuusuke Morii; Motohiro Imano; Takao Satou; Kazunori Shimomura; Shozo Nishida
    International journal of molecular sciences 21 21 2020年10月 
    Multiple myeloma (MM)-induced bone disease occurs through hyperactivation of osteoclasts by several factors secreted by MM cells. MM cell-secreted factors induce osteoclast differentiation and activation via direct and indirect actions including enhanced expression of receptor activator of nuclear factor κB ligand (RANKL) in osteoblasts and bone marrow stromal cells (BMSCs). Hepatocyte growth factor (HGF) is elevated in MM patients and is associated with MM-induced bone disease, although the mechanism by which HGF promotes bone disease remains unclear. In the present study, we demonstrated that HGF induces RANKL expression in osteoblasts and BMSCs, and investigated the mechanism of induction. We found that HGF and MM cell supernatants induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. In addition, HGF increased phosphorylation of Met and nuclear factor κB (NF-κB) in ST2 cells, MC3T3-E1 cells, or mouse BMSCs. Moreover, Met and NF-κB inhibitors suppressed HGF-induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. These results indicated that HGF promotes RANKL expression in osteoblasts and BMSCs via the Met/NF-κB signaling pathway, and Met and NF-κB inhibitors suppressed HGF-induced RANKL expression. Our findings suggest that Met and NF-κB inhibitors are potentially useful in mitigating MM-induced bone disease in patients expressing high levels of HGF.
  • T Takeda; M Tsubak; S Genno; T Matsuda; Y Yamamoto; E Ueda; M Imano; T Satou; S Nishida
    Journal of physiology and pharmacology : an official journal of the Polish Physiological Society 71 4 2020年08月 
    Burkitt lymphoma (BL) is a highly aggressive form of non-Hodgkin's B-cell lymphoma. Currently, multi-agent chemotherapy regimens are being used to significantly improve cure rates and achieve complete remissions in BL patients. However, drug resistance can often occur within 6 months in BL patients, contributing to poor prognosis. Mounting evidence suggests that cell adhesion-mediated drug resistance (CAM-DR), caused by the interaction between the bone marrow microenvironment and tumour cells may play an important role in drug resistance to chemotherapy. However, the molecular mechanism underlying CAM-DR in BL has not been identified yet. In this study, we investigated the molecular mechanism responsible for CAM-DR in BL cells. We also examined the therapeutic targets of CAM-DR in BL cells and found CD49d and CD49e to be the important adhesion molecules involved. However, CD49a, CD49b, CD11a, CD29, CD18, and CD61 were not found to be associated with CAM-DR in BL cells. Furthermore, we clarified that CD49d- and CD49e-mediated CAM-DR could be attributed to an increase in the expression of B cell leukemia-xL (Bcl-xL) and survivin proteins, and a decrease in the expression of Bcl-2 associated X (Bax), Bcl-2 interacting mediator (Bim) and p53 upregulated modulator of apoptosis (PUMA) proteins via nuclear factor kappaB (NF-κB) activation. In addition, bortezomib was found to overcome CAM-DR in BL cells by inhibiting NF-κB. Thus, bortezomib may have potential clinical applications in the treatment of CD49d- and CD49e-mediated CAM-DR in BL patients.
  • Tomoya Takeda; Masanobu Tsubaki; Ryota Asano; Tatsuki Itoh; Motohiro Imano; Takao Satou; Shozo Nishida
    Journal of dermatological science 99 3 168 - 176 2020年07月 [査読有り]
     
    BACKGROUND: Malignant melanoma is among the deadliest forms of skin cancers, and its incidence has been increasing over the past decades. In malignant melanoma, activation of the nuclear factor kappa B (NF-κB) promotes survival, migration, and invasion of cancer cells. Anti-NF-κB agents for treating metastatic melanoma would be beneficial, but no such drug is approved as either monotherapy or adjuvant therapy. Dimethyl fumarate (DMF) is an approved anti-inflammatory drug already in clinical use for psoriasis and multiple sclerosis. OBJECTIVE: We investigated the anti-tumour effect of DMF treatment in metastatic melanoma in vitro and in vivo. METHODS: The cell viability was assessed via trypan blue exclusion assay. The migration and invasion was analyzed in a Boyden chamber assay. The anti-metastatic effects and anti-tumour activity of DMF was determined in an in-vivo model. The expressions of NF-κB pathway and NF-κB regulatory proteins were detected via western blotting. RESULTS: DMF decreased the cell viability, migration and invasion in vitro. In addition, DMF inhibited spontaneous metastasis and tumour growth. Mechanistically, DMF prevented the nuclear translocation of NF-κB, whereas no changes were observed in the phosphorylation levels of inhibitor of kappa B (IκB). In addition, DMF inhibited the expression of matrix metalloproteinases (MMPs) and very late antigens (VLAs). Furthermore, DMF treatment decreased the expression of Survivin and Bcl-extra large (Bcl-XL) proteins. CONCLUSION: Our results suggest that DMF as a novel inhibitor of NF-κB may be a potential therapeutic agent for metastatic melanoma.
  • Keiji Mashimo; Daichiro Fujiwara; Tadafumi Hoshida; Naomi Morimoto; Akihiro Noda; Tomoya Takeda; Masanobu Tsubaki; Shozo Nishida; Katsuhiko Sakaguchi
    Gan to kagaku ryoho. Cancer & chemotherapy 47 6 993 - 995 2020年06月 [査読有り]
     
    We had cases in which peripheral neuropathy was augmented after changing from mFOLFOX6, a chemotherapy for colorectal cancer, to FOLFIRI and comparatively examined disease status and trends. There were no shared points with respect to patient characteristics, timing of peripheral neuropathy augmentation, drug dosage, etc. It appeared that the change in chemotherapy itself had an effect on neuropathic symptoms. Regarding the change in chemotherapy, the therapeutic agent was switched from oxaliplatin to irinotecan; the cause was unknown, but some effects of these two drugs were suggested. Future investigation, including the examination of genetic mutations, is necessary.
  • Mitsuki Tabata; Masanobu Tsubaki; Tomoya Takeda; Keisuke Tateishi; Katsumasa Tsurushima; Motohiro Imano; Takao Satou; Toshihiko Ishizaka; Shozo Nishida
    BMC complementary medicine and therapies 20 1 84 - 84 2020年03月 [査読有り]
     
    BACKGROUND: Current chemotherapies for Burkitt lymphoma (BL) have dramatically improved its clinical outcome. However, chemoresistance can lead to chemotherapy failure and very poor prognosis; thus, novel strategies are urgently required for patients with drug-resistant BL. To investigate the mechanisms underlying drug resistance in BL, we established drug-resistant BL cell lines: HS-Sultan/ADM (adriamycin-resistant), HS-Sultan/VCR (vincristine-resistant), HS-Sultan/DEX (dexamethasone-resistant), and HS-Sultan/L-PAM (melphalan-resistant). METHODS: Drug transporter and survival factor expression were investigated the using western blotting and real time polymerase chain reaction. Cell survival was analyzed by trypan blue dye exclusion method. RESULTS: The established cell lines acquired cross-resistance to adriamycin, vincristine, dexamethasone, and melphalan and exhibited 50% inhibitory concentration values 106-, 40-, 81-, and 45-fold higher than the parental cell lines, respectively. We found that protein and mRNA expression of MDR1 and Survivin were higher in drug-resistant BL cells than in the parent cells. Treatment with verapamil, an MDR1 inhibitor, or Survivin siRNA alongside each anti-cancer drug suppressed the proliferation of all drug-resistant BL cells. Src kinase activity was higher in all resistant cell lines than the parental cells; suppressing Src with dasatinib restored drug sensitivity by reducing MDR1 and Survivin expression. CONCLUSIONS: MDR1 and Survivin upregulation are responsible for resistance to conventional drugs and dasatinib can restore drug sensitivity by reducing MDR1 and Survivin expression in drug-resistant BL cells. Src inhibitors could therefore be a novel treatment strategy for patients with drug resistant BL.
  • Mitsuki Tabata; Masanobu Tsubaki; Tomoya Takeda; Keisuke Tateishi; Saho Maekawa; Katsumasa Tsurushima; Motohiro Imano; Takao Satou; Toshihiko Ishizaka; Shozo Nishida
    Clinical and experimental medicine 20 1 63 - 71 2020年02月 [査読有り]
     
    Multiple myeloma (MM) is the second most common hematologic malignancy. In spite of the development of new therapeutic agents, MM remains incurable due to multidrug resistance (MDR) and the 5-year survival rate is approximately 50%. Thus, further study is needed to investigate the mechanism of MDR and improve MM prognosis. Heat shock protein 90 (HSP90) is a molecular chaperone that is responsible for the stability of a number of client proteins, most of which are involved in tumor progression. Therefore, HSP90 inhibitors represent potential new therapeutic agents for cancer. Furthermore, inhibition of HSP90 leads to degradation of client proteins, overcoming acquired anti-cancer drug resistance. In this study, we assessed the role of HSP90 in MDR using established melphalan-resistant MM cells. We found that expression of HSP90 was higher in melphalan-resistant MM cells than in parent cells and that HSP90 inhibitors KW-2478 and NUV-AUY922 restored drug sensitivity to the level observed in parent cells. Activation of the unfolded protein response is a hallmark of MM, and expression of endoplasmic reticulum stress signaling molecules is reduced in melphalan-resistant cells; however, KW-2478 did not affect endoplasmic reticulum stress signaling. We demonstrated that treatment with KW-2478 decreased expression of Src, a client of HSP90, and suppressed the activity of ERK, Akt, and NF-κB. Our findings indicate that inhibition of HSP90 results in suppression of Src and its downstream effectors, including ERK, Akt, and NF-κB, and therefore that HSP90 inhibitors could be useful for treatment of MDR MM.
  • Masanobu Tsubaki; Tomoya Takeda; Masaki Noguchi; Minami Jinushi; Shiori Seki; Yuusuke Morii; Kazunori Shimomura; Motohiro Imano; Takao Satou; Shozo Nishida
    Cancers 11 12 2019年11月 [査読有り]
     
    RAS and BRAF-mutated colorectal cancers are associated with resistance to chemotherapy and poor prognosis, highlighting the need for new therapeutic strategies. Although these cancers sometimes respond to mitogen activated protein kinase kinase (MEK) inhibitor treatment, they often acquire resistance via mechanisms, which are poorly understood. Here, we investigated the mechanism of MEK inhibitor resistance in primary- and acquired-resistant cells. Cell viability was examined using the trypan blue dye exclusion assay. Protein expression was analyzed by western blotting. Somatic mutations in colorectal cancer cells were investigated using the polymerase chain reaction array. PD0325901 and trametinib induced cell death in LoVo and Colo-205 cells but not in DLD-1 and HT-29 cells, which have a PIK3CA mutation constitutively activating Akt and NF-κB. Treatment with PD0325901 and trametinib suppressed ERK1/2 activation in all four cell lines but only induced Akt and NF-κB activation in DLD-1 and HT-29 cells. Inhibition of Akt but not NF-κB, overcame MEK inhibitor resistance in DLD-1 and HT-29 cells. Acquired-resistant LoVo/PR, Colo-205/PR and LoVo/TR cells have constitutively active Akt due to a M1043V mutation in the kinase activation loop of PIK3CA and Akt inhibitor resensitized these cells to MEK inhibitor. These results demonstrate that the overactivation of Akt plays a critical role in MEK inhibitor primary and acquired resistance and implicate combined Akt/MEK inhibition as a potentially useful treatment for RAS/BRAF-mutated colorectal cancer.
  • Masanobu Tsubaki; Tomoya Takeda; Naoya Obata; Keishi Kawashima; Mitsuki Tabata; Motohiro Imano; Takao Satou; Shozo Nishida
    Journal of cellular physiology 234 10 17975 - 17989 2019年08月 [査読有り]
     
    Malignant melanoma is a highly aggressive skin cancer, and the overall median survival in patients with metastatic melanoma is only 6-9 months. Although molecular targeted therapies have recently been developed and have improved the overall survival, melanoma patients may show no response and acquisition of resistance to these drugs. Thus, other molecular approaches are essential for the treatment of metastatic melanoma. In the present study, we investigated the effect of cotreatment with dacarbazine and statins on tumor growth, metastasis, and survival rate in mice with metastatic melanomas. We found that cotreatment with dacarbazine and statins significantly inhibited tumor growth and metastasis via suppression of the RhoA/RhoC/LIM domain kinase/serum response factor/c-Fos pathway and enhanced p53, p21, p27, cleaved caspase-3, and cleaved poly(ADP-ribose) polymerase 1 expression in vivo. Moreover, the cotreatment significantly improved the survival rate in metastasis-bearing mice. Importantly, treatment with dacarbazine plus 100 mg/kg simvastatin or fluvastatin prevented metastasis-associated death in 4/20 mice that received dacarbazine + simvastatin and in 8/20 mice that received dacarbazine + fluvastatin (survival rates, 20% and 40%, respectively). These results suggested that cotreatment with dacarbazine and statins may thus serve as a new therapeutic approach to control tumor growth and metastasis in melanoma patients.
  • Keiji Mashimo; Masanobu Tsubaki; Tomoya Takeda; Ryota Asano; Minami Jinushi; Motohiro Imano; Takao Satou; Katsuhiko Sakaguchi; Shozo Nishida
    Clinical and experimental medicine 19 1 133 - 141 2019年02月 [査読有り]
     
    The survival and growth of multiple myeloma (MM) cells are facilitated by cell-cell interactions with bone marrow stromal cells and the bone marrow microenvironment. These interactions induce de novo drug resistance known as cell adhesion-mediated drug resistance. Our previous results recently revealed that the receptor activator of NF-κB (RANK) ligand (RANKL), which is expressed by bone marrow stromal cells, contributes to anti-cancer drug resistance through the activation of various signaling molecules and suppression of Bim expression in RANK-expressing MM cells. However, the detailed mechanisms underlying RANKL-induced drug resistance remain uncharacterized. In the present study, we investigated the mechanism of RANKL-induced drug resistance in RANK-expressing MM cell lines. We found treatment of MM cells with RANKL-induced c-Src phosphorylation and activation of the downstream signaling molecules Akt, mTOR, STAT3, JNK, and NF-κB. In addition, treatment with dasatinib, a c-Src inhibitor, overcame RANKL- and bone marrow stromal cell-induced drug resistance to adriamycin, vincristine, dexamethasone, and melphalan by suppressing c-Src, Akt, mTOR, STAT3, JNK, and NF-κB activation and enhancing expression of Bim. Overall, RANKL- and bone marrow stromal cell-induced drug resistance correlated with the activation of c-Src signaling pathways, which caused a decrease in Bim expression. Dasatinib treatment of RANK-expressing MM cells re-sensitized them to anti-cancer drugs. Therefore, inhibition of c-Src may be a new therapeutic approach for overcoming RANKL-induced drug resistance in patients with MM.
  • Tsubaki M; Takeda T; Tomonari Y; Koumoto YI; Imano M; Satou T; Nishida S
    Laboratory investigation; a journal of technical methods and pathology 99 1 72 - 84 2019年01月 [査読有り]
     
    Multiple myeloma (MM) commonly displays multidrug resistance and is associated with poor prognosis. Therefore, it is important to identify the mechanisms by which MM cells develop multidrug resistance. Our previous study showed that multidrug resistance is correlated with overexpression of multidrug resistance protein 1 (MDR1) and Survivin, and downregulation of Bim expression in melphalan-resistant RPMI8226/L-PAM cells; however, the underlying mechanism of multidrug resistance remains unclear. In the present study, we investigated the mechanism of multidrug resistance in melphalan-resistant cells. We found that RPMI8226/L-PAM and ARH-77/L-PAM cells showed increased phosphorylation of extracellular signal-regulated protein kinase 1/2 (ERK1/2) and Akt, and nuclear localization of nuclear factor κB (NF-κB). The combination of ERK1/2, Akt, and NF-κB inhibitors with melphalan reversed melphalan resistance via suppression of Survivin expression and enhanced Bim expression in melphalan-resistant cells. In addition, RPMI8226/L-PAM and ARH-77/L-PAM cells overexpressed hypoxia-inducible factor 1α (HIF-1α) via activation of ERK1/2, Akt, and NF-κB. Moreover, suppression of HIF-1α by echinomycin or HIF-1α siRNA resensitized RPMI8226/L-PAM cells to melphalan through downregulation of Survivin expression and upregulation of Bim expression. These results indicate that enhanced Survivin expression and decreased Bim expression by HIF-1α via activation of ERK1/2, Akt, and NF-κB play a critical role in melphalan resistance. Our findings suggest that HIF-1α, ERK1/2, Akt, and NF-κB inhibitors are potentially useful as anti-MDR agents for the treatment of melphalan-resistant MM.
  • 婦人科悪性腫瘍におけるパクリタキセル・カルボプラチン療法での後発品製剤安全性の検討
    藤本伸一郎; 柳江正嗣; 淺野肇; 武田朋也; 椿正寛; 藤原季美子; 月岡康行; 松野純男; 森嶋祥之; 西田升三
    ジェネリック研究 12 2 74 - 79 2018年12月 [査読有り]
     
    わが国では後発医薬品への切り替えが推進されているが、切り替え時の問題点として、臨床試験における同等性の報告が義務付けられていないことが挙げられる。安全域が狭いがん化学療法の分野において、切り替えによる有害事象発現の差異が治療に影響する可能性は高く、実臨床での薬剤評価が必要と考える。しかし、後発医薬品への切り替えに際し、製剤毎での比較報告はあるものの、後発医薬品を併用したレジメンとしての報告は少なく、十分なエビデンスが少ないなかで治療が行われているのが現状である。本検討では婦人科悪性腫瘍における重要なレジメンである、パクリタキセル・カルボプラチン療法における切り替えによる安全性の差異を確認した。結果として、血液毒性、筋肉痛及び関節痛については、切り替え後も同等である可能性が示唆された。他の非血液毒性については、切り替えによりオッズ比は低下傾向であったが、同等性は保証されなかった。また、治療中に減量を必要とした症例数に有意な差は認められず、切り替え後も安全性が保たれていることが示唆された。今後も症例数を重ね、より科学的根拠のある報告をする必要がある。(著者抄録)
  • Masanobu Tsubaki; Tomoya Takeda; Mikihiro Matsumoto; Natsuki Kato; Shota Yasuhara; Yu-Ichi Koumoto; Motohiro Imano; Takao Satou; Shozo Nishida
    Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine 40 10 1010428318808670 - 1010428318808670 2018年10月 [査読有り]
     
    Chemotherapy-induced neuropathy is a highly problematic, dose-limiting effect of potentially curative regimens of cancer chemotherapy. When neuropathic pain is severe, patients often either switch to less-effective chemotherapy agents or choose to discontinue chemotherapy entirely. Conventional chemotherapy drugs used to treat lung and breast cancer, multiple myeloma, and lymphoma include paclitaxel, vincristine, and bortezomib. Approximately 68% of patients receiving these anticancer drugs develop neuropathy within the first month of treatment, and while strategies to prevent chemotherapy-induced neuropathy have been investigated, none have yet been proven as effective. Recent reports suggest that chemotherapy-induced neuropathy is associated with signal transduction molecules, including protein kinase C and mitogen-activated protein kinases. It is currently unclear whether protein kinase C inhibition can prevent chemotherapy-induced neuropathy. In this study, we found that tamoxifen, a protein kinase C inhibitor, suppressed paclitaxel-, vincristine-, and bortezomib-induced cold and mechanical allodynia in mice. In addition, chemotherapy drugs induce neuropathy via the protein kinase C/extracellular signal-regulated kinase pathway in the spinal cord in lumbar segments 4-6 and dorsal root ganglions. In addition, tamoxifen was shown to act synergistically with paclitaxel to inhibit tumor-growth in mice injected with tumor cells. Our results indicated that paclitaxel-, vincristine-, and bortezomib-induced neuropathies were associated with the protein kinase C/extracellular signal-regulated kinase pathway in the lumbar spinal cord and dorsal root ganglions, which suggest that protein kinase C inhibitors may be therapeutically effective for the prevention of chemotherapy-induced neuropathy when administered with standard chemotherapy agents.
  • Tsubaki M; Takeda T; Tomonari Y; Mashimo K; Koumoto YI; Hoshida S; Itoh T; Imano M; Satou T; Sakaguchi K; Nishida S
    Journal of cellular physiology 233 5 4258 - 4271 2018年05月 [査読有り]
     
    Several autocrine soluble factors, including macrophage inflammatory protein-1α (MIP-1α), tumor necrosis factor-α, and hepatocyte growth factor, promote cell survival and growth in multiple myeloma (MM) cells. We hypothesized that inhibition of the MIP-1α autocrine loop may enhance the cytotoxic effect of anticancer drugs in MM cell lines. In the present study, an MIP-1α neutralizing antibody suppressed cell proliferation and enhanced the cytotoxic effect of melphalan or bortezomib on MM cells. In addition, melphalan resistance cells (RPMI8226/L-PAM and HS-sultan/L-PAM cells) secreted MIP-1α and neutralizing antibody of MIP-1α partially overcame melphalan resistance. Moreover, combination treatment with MIP-1α neutralizing antibody and melphalan or bortezomib inhibited extracellular signal regulated kinase 1/2 (ERK1/2), Akt, and mammalian target of rapamycin (mTOR) activation, Bcl-2, Bcl-xL, and Survivin expression, and upregulated the expression of Bim and cleaved Poly (ADP-ribose) polymerase (PARP). Treatment of IM9 cells with MIP-1α siRNA suppressed the activation of ERK1/2, Akt, and mTOR, and enhanced the cytotoxic effect of melphalan and bortezomib. These results indicate that MIP-1α neutralizing antibodies or MIP-1α siRNA enhance the cytotoxic effect of melphalan and bortezomib by suppressing the chemokine receptor/ERK and chemokine receptor/Akt/mTOR pathways. The inhibition of MIP-1α may thus provide a new therapeutic approach to control tumor progression and bone destruction in patients with MM.
  • Tsubaki M; Takeda T; Tomonari Y; Kawashima K; Itoh T; Imano M; Satou T; Nishida S
    Journal of cellular physiology 233 4 3638 - 3647 2018年04月 [査読有り]
     
    Pioglitazone is an anti-diabetic agent that belongs to the thiazolidinedione class, which target peroxisome proliferator-activated receptor γ (PPARγ), a transcription factor in the nuclear receptor family. Different cancer cells expressing high levels of PPARγ and PPARγ ligands induce cell cycle arrest, cell differentiation, and apoptosis. However, the mechanisms underlying these processes remain unknown. Here, we investigated the mechanism underlying pioglitazone-induced apoptosis in human cancer cells. We showed that at similar concentrations, pioglitazone induced death in cancer cells expressing high or low levels of PPARγ. Combined treatment of pioglitazone and GW9662, a PPARγ antagonist, did not rescue this cell death phenotype. Z-VAD-fmk, a pan-caspase inhibitor, did not reverse pioglitazone-induced apoptosis in cancer cells expressing PPARγ at high or low levels. Pioglitazone suppressed the activation of signal transducers and activator of transcription 3 (STAT3) and Survivin expression, and enhanced the apoptosis-inducing factor (AIF) levels in these cells. Furthermore, pioglitazone enhanced the cytotoxic effect of cisplatin and oxaliplatin by suppressing Survivin and increasing AIF expression. These results indicated that pioglitazone induced apoptosis via a PPARγ-independent pathway, thus describing pioglitazone as a potential therapeutic agent for controlling the progression of different cancers.
  • Tomoya Takeda; Masanobu Tsubaki; Yoshika Tomonari; Keishi Kawashima; Tatsuki Itoh; Motohiro Imano; Takao Satou; Shozo Nishida
    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 100 486 - 494 2018年04月 [査読有り]
     
    Bavachin is a phytoestrogen purified from natural herbal plants such as Psoralea corylifolia. In this study, we examined the effect of bavachin in multiple myeloma (MM) cell lines. We found that bavachin decreased the viability of MM cell lines, but was not cytotoxic towards normal cells. It inhibited the activation of nuclear factor kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3). Furthermore, bavachin increased the expression of p53 and NOXA, and decreased the expression of X-linked inhibitor of apoptosis protein (XIAP), survivin, B cell lymphoma-extra large (Bcl-xL), and Bcl-2. Additionally, bavachin induced apoptosis by the activation of caspase-3 and caspase-9, implicating the involvement of the mitochondrial pathway. Our results suggest that bavachin induces apoptosis through the inhibition of NF-κB and STAT3 activation in MM cell lines. Most importantly, few NF-κB and STAT3 inhibitors with high efficiency, specificity, and safety are currently available for clinical cancer therapy. Hence, bavachin, which targets NF-κB and STAT3, is a potential anticancer agent for the treatment of MM.
  • Masanobu Tsubaki; Tomoya Takeda; Ryo-Ta Asano; Tomoyuki Matsuda; Shin-Ichiro Fujimoto; Tatsuki Itoh; Motohiro Imano; Takao Satou; Shozo Nishida
    Toxicology in vitro : an international journal published in association with BIBRA 46 284 - 293 2018年02月 [査読有り]
     
    Oral mucositis is a common adverse effect of chemotherapy that limits the required dose of chemotherapeutic agents. Numerous attempts to mitigate chemotherapy-induced oral mucositis have failed to identify an appropriate treatment. Recently, it has been indicated that rebamipide prevents chemoradiotherapy-induced oral mucositis in patients. However, the details of the underlying mechanism involved in the cytoprotective effect of rebamipide remain obscure. In the present study, we investigated the mechanism behind rebamipide cytoprotective effect in the oral mucosa using primary normal human oral keratinocytes (NHOK cells). We found that rebamipide prevented 5-fluorouracil (5-FU)-induced cell death in NHOK cells. In addition, rebamipide increased the levels of phosphorylated Akt and mTOR, enhanced the Bcl-2 and Bcl-xL expressions, and suppressed the expression of Bax and Bim. This is in contrast to 5-FU-induced suppression of Akt and mTOR activation, Bcl-2 and Bcl-xL expressions, and the enhanced expression of Bax and Bim. These findings suggest that rebamipide can potentially be used for the protection of oral mucosa from chemotherapy-induced mucositis. This is the first study that elucidates the specific molecular pathway for the cytoprotective effect of rebamipide.
  • Masanobu Tsubaki; Tomoya Takeda; Mikihiro Matsumoto; Natsuki Kato; Ryo-Ta Asano; Motohiro Imano; Takao Satou; Shozo Nishida
    American journal of cancer research 8 7 1239 - 1248 2018年 [査読有り]
     
    Chemotherapy-induced neuropathy is a common, dose-dependent adverse effect of some anti-cancer drugs and leads to discontinuation of chemotherapy and detrimental dose reductions, thereby affecting the quality of life of cancer patients. Currently, no treatment can effectively prevent or treat chemotherapy-induced neuropathy. Therefore, understanding its underlying molecular mechanisms may help to identify novel therapies for treating it. Some disease-induced neuropathy involve the activation of mitogen-activated protein kinases (MAPKs), such as extracellular-regulated protein kinase 1/2 (ERK1/2). In the present study, we investigated whether ERK1/2 inhibition can prevent chemotherapy-induced neuropathy. We found that trametinib, an MEK inhibitor, suppressed oxaliplatin-, paclitaxel-, vincristine-, and bortezomib-induced cold and mechanical allodynia in mice. In addition, treatment with oxaliplatin, paclitaxel, vincristine, or bortezomib enhanced ERK1/2 and c-Jun N-terminal kinase (JNK) phosphorylation in the spinal cord lumbar segments 4-6, and when combined with trametinib, can prevent chemotherapy-induced neuropathy via the suppression of ERK1/2 activation, but does not affect JNK activation. In conclusion, we demonstrated that the disruption of this pathway by MEK inhibitors suppresses oxaliplatin-, paclitaxel-, vincristine-, and bortezomib-induced neuropathy. This suggests that inhibition of the MEK/ERK pathway could prevent chemotherapy-induced neuropathy and MEK inhibitors could be used in combination with anti-tumor drugs during pharmacotherapy.
  • Daichiro Fujiwara; Masanobu Tsubaki; Tomoya Takeda; Yoshika Tomonari; Yu-Ichi Koumoto; Katsuhiko Sakaguchi; Shozo Nishida
    Tumor Biology 39 10 1 - 12 2017年10月 [査読有り]
     
    Recently, statins have been demonstrated to improve cancer-related mortality or prognosis in patients of various cancers. However, the details of the apoptosis-inducing mechanisms remain unknown. This study showed that the induction of apoptosis by statins in hematopoietic tumor cells is mediated by mitochondrial apoptotic signaling pathways, which are activated by the suppression of mevalonate or geranylgeranyl pyrophosphate biosynthesis. In addition, statins decreased the levels of phosphorylated extracellular signal–regulated kinase 1/2 and mammalian target of rapamycin through suppressing Ras prenylation. Furthermore, inhibition of extracellular signal–regulated kinase 1/2 and mammalian target of rapamycin by statins induced Bim expression via inhibition of Bim phosphorylation and ubiquitination and cell-cycle arrest at G1 phase via enhancement of p27 expression. Moreover, combined treatment of U0126, a mitogen-activated protein kinase kinase 1/2 inhibitor, and rapamycin, a mammalian target of rapamycin inhibitor, induced Bim and p27 expressions. The present results suggested that statins induce apoptosis by decreasing the mitochondrial transmembrane potential, increasing the activation of caspase-9 and caspase-3, enhancing Bim expression, and inducing cell-cycle arrest at G1 phase through inhibition of Ras/extracellular signal–regulated kinase and Ras/mammalian target of rapamycin pathways. Therefore, our findings support the use of statins as potential anticancer agents or concomitant drugs of adjuvant therapy.
  • Masanobu Tsubaki; Tomoya Takeda; Toshiki Kino; Kazuko Sakai; Tatsuki Itoh; Motohiro Imano; Takashi Nakayama; Kazuto Nishio; Takao Satou; Shozo Nishida
    Oncotarget 8 24 38717 - 38730 2017年06月 [査読有り]
     
    Resistance to the breakpoint cluster region-abelson 1 (BCR-ABL1) tyrosine kinase inhibitor (TKI) imatinib poses a major problem when treating chronic myeloid leukemia (CML). Imatinib resistance often results from a secondary mutation in BCR-ABL1. However, in the absence of a mutation in BCR-ABL1, the basis of BCR-ABL1-independent resistance must be elucidated. To gain insight into the mechanisms of BCR-ABL1-independent imatinib resistance, we performed an array-based comparative genomic hybridization. We identified various resistance-related genes, and focused on MET. Treatment with a MET inhibitor resensitized K562/IR cells to BCR-ABL1 TKIs. Combined treatment of K562/IR cells with imatinib and a MET inhibitor suppressed extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK) activation, but did not affect AKT activation. Our findings implicate the MET/ERK and MET/JNK pathways in conferring resistance to imatinib, providing new insights into the mechanisms of BCR-ABL1 TKI resistance in CML.
  • Masanobu Tsubaki; Daichiro Fujiwara; Tomoya Takeda; Toshiki Kino; Yoshika Tomonari; Tatsuki Itoh; Motohiro Imano; Takao Satou; Katsuhiko Sakaguchi; Shozo Nishida
    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY 44 2 222 - 234 2017年02月 [査読有り]
     
    Statins induce apoptosis of tumour cells by inhibiting the prenylation of small G-proteins. However, the details of the apoptosis-inducing mechanisms remain poorly understood. The present study showed that the induction of apoptosis by statins in four different human head and neck squamous cell carcinoma ( HNSCC) cell lines, HSC-3, HEp-2, Ca9-22, and SAS cells was mediated by increased caspase-3 activity. Statins induced apoptosis by the suppression of geranylgeranyl pyrophosphate biosynthesis. Furthermore, statins decreased the levels of phosphorylated ERK and mTOR by inhibiting the membrane localization of Ras and enhancing Bim expression in HSC-3 and HEp-2 cells. We also found that in all the cell types analyzed, the IC50 values for fluvastatin and simvastatin were highest in HEp-2 cells. In addition, HSC-3, Ca9-22, and SAS cells had higher Ras expression and membrane localization, higher activation of ERK1/2 and mTOR, and lower levels of Bim expression than HEp-2 cells. Our results indicate that statins induce apoptosis by increasing the activation of caspase-3 and by enhancing Bim expression through inhibition of the Ras/ERK and Ras/mTOR pathways. Furthermore, the sensitivity of HNSCC cells to statin treatment was closely related to Ras expression and prenylation levels, indicating that statins may act more effectively against tumours with high Ras expression and Ras-variability. Therefore, our findings support the use of statins as potential anticancer agents.
  • Daichiro Fujiwara; Keiji Mashimo; Kayo Kimura; Akihiro Noda; Kazuo Taki; Hiroshi Yoshibayashi; Tomoya Takeda; Masanobu Tsubaki; Shozo Nishida; Katsuhiko Sakaguchi
    Japanese Journal of Cancer and Chemotherapy 44 2 149 - 152 2017年02月 [査読有り]
     
    Febrile neutropenia (FN) is one of the serious treatment-related toxicities after FEC 100 (5-fluorouracil 500 mg/m2, epirubicin 100 mg/m2, cyclophosphamide 500 mg/m2) chemotherapy for breast cancer. Granulocyte-colony stimulating factor (GCSF) is used as a support therapy for FN. Thus, we evaluated retrospectively the safety of administering pegfilgrastim the day after FEC100 chemotherapy in Japanese patients with breast cancer as compared with lenograstim. Grade 3 or 4 neutropenia was observed in 91.7% patients after pegfilgrastim administration and in 63.2% after lenograstim. The incidence rate of FN was 7.0% after pegfilgrastim administration and 9.7% after lenograstim, a difference that was not significantly different (p= 0.741). The mean relative dose intensity was good at 0.98 for pegfilgrastim and 0.97 for lenograstim. In conclusion, pegfilgrastim is not inferior to lenograstim in the incidence of FN. However, we do not recommend administering pegfilgrastim on the day after FEC100 therapy because it causes more severe neutropenia and has a high risk of FN. The timing of administration of pegfilgrastim in FEC 100 therapy requires further study.
  • Masanobu Tsubaki; Daichiro Fujiwara; Tomoya Takeda; Toshiki Kino; Yoshika Tomonari; Tatsuki Itoh; Motohiro Imano; Takao Satou; Katsuhiko Sakaguchi; Shozo Nishida
    Clinical and experimental pharmacology & physiology 44 2 222 - 234 2017年02月 [査読有り]
     
    Statins induce apoptosis of tumour cells by inhibiting the prenylation of small G-proteins. However, the details of the apoptosis-inducing mechanisms remain poorly understood. The present study showed that the induction of apoptosis by statins in four different human head and neck squamous cell carcinoma (HNSCC) cell lines, HSC-3, HEp-2, Ca9-22, and SAS cells was mediated by increased caspase-3 activity. Statins induced apoptosis by the suppression of geranylgeranyl pyrophosphate biosynthesis. Furthermore, statins decreased the levels of phosphorylated ERK and mTOR by inhibiting the membrane localization of Ras and enhancing Bim expression in HSC-3 and HEp-2 cells. We also found that in all the cell types analyzed, the IC50 values for fluvastatin and simvastatin were highest in HEp-2 cells. In addition, HSC-3, Ca9-22, and SAS cells had higher Ras expression and membrane localization, higher activation of ERK1/2 and mTOR, and lower levels of Bim expression than HEp-2 cells. Our results indicate that statins induce apoptosis by increasing the activation of caspase-3 and by enhancing Bim expression through inhibition of the Ras/ERK and Ras/mTOR pathways. Furthermore, the sensitivity of HNSCC cells to statin treatment was closely related to Ras expression and prenylation levels, indicating that statins may act more effectively against tumours with high Ras expression and Ras-variability. Therefore, our findings support the use of statins as potential anticancer agents.
  • Tomoya Takeda; Masanobu Tsubaki; Kotaro Sakamoto; Eri Ichimura; Aya Enomoto; Yuri Suzuki; Tatsuki Itoh; Motohiro Imano; Genzoh Tanabe; Osamu Muraoka; Hideaki Matsuda; Takao Satou; Shozo Nishida
    Toxicology and applied pharmacology 306 105 - 12 2016年09月 [査読有り]
     
    Advanced metastatic melanoma, one of the most aggressive malignancies, is currently without reliable therapy. Therefore, new therapies are urgently needed. Mangiferin is a naturally occurring glucosylxanthone and exerts many beneficial biological activities. However, the effect of mangiferin on metastasis and tumor growth of metastatic melanoma remains unclear. In this study, we evaluated the effect of mangiferin on metastasis and tumor growth in a mouse metastatic melanoma model. We found that mangiferin inhibited spontaneous metastasis and tumor growth. Furthermore, mangiferin suppressed the nuclear translocation of nuclear factor kappa B (NF-κB) and expression of phosphorylated NF-κB-inducing kinase (NIK), inhibitor of kappa B kinase (IKK), and inhibitor of kappa B (IκB) and increases the expression of IκB protein in vivo. In addition, we found that mangiferin inhibited the expression of matrix metalloproteinases (MMPs) and very late antigens (VLAs) in vivo. Mangiferin treatment also increased the expression of cleaved caspase-3, cleaved Poly ADP ribose polymerase-1 (PARP-1), p53 upregulated modulator of apoptosis (PUMA), p53, and phosphorylated p53 proteins, and decreased the expression of Survivin and Bcl-associated X (Bcl-xL) proteins in vivo. These results indicate that mangiferin selectivity suppresses the NF-κB pathway via inhibition of NIK activation, thereby inhibiting metastasis and tumor growth. Importantly, the number of reported NIK selective inhibitors is limited. Taken together, our data suggest that mangiferin may be a potential therapeutic agent with a new mechanism of targeting NIK for the treatment of metastatic melanoma.
  • Masanobu Tsubaki; Tomoya Takeda; Misako Yoshizumi; Emi Ueda; Tatsuki Itoh; Motohiro Imano; Takao Satou; Shozo Nishida
    Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine 37 7 9099 - 110 2016年07月 [査読有り]
     
    Interaction between multiple myeloma (MM) cells and the bone marrow microenvironment plays a critical role in MM pathogenesis and the development of drug resistance. Recently, it has been reported that MM cells express the receptor activator of nuclear factor-κB (NF-κB) (RANK). However, the role of the RANK/RANK ligand (RANKL) system in drug resistance remains unclear. In this study, we demonstrated a novel function of the RANK/RANKL system in promoting drug resistance in MM. We found that RANKL treatment induced drug resistance in RANK-expressing but not RANK-negative cell lines. RANKL stimulation of RANK-expressing cells increased multidrug resistance protein 1 (MDR1), breast cancer resistance protein (BCRP), and lung resistance protein 1 (LRP1) expression and decreased Bim expression through various signaling molecules. RNA silencing of Bim expression induced drug resistance, but the RANKL-mediated drug resistance could not be overcome through the RNA silencing of MDR1, BCRP, and LRP1 expression. These results indicate that the RANK/RANKL system induces chemoresistance through the activation of multiple signal transduction pathways and by decreasing Bim expression in RANK-positive MM cells. These findings may prove to be useful in the development of cell adhesion-mediated drug resistance inhibitors in RANK-positive MM cells.
  • Takeda T; Tsubaki M; Kino T; Kawamura A; Isoyama S; Itoh T; Imano M; Tanabe G; Muraoka O; Matsuda H; Satou T; Nishida S
    International journal of oncology 48 6 2704 - 12 2016年06月 [査読有り]
     
    Multiple myeloma (MM) is still an incurable hematological malignancy with a 5-year survival rate of ~35%, despite the use of various treatment options. The nuclear factor κB (NF-κB) pathway plays a crucial role in the pathogenesis of MM. Thus, inhibition of the NF-κB pathway is a potential target for the treatment of MM. In a previous study, we showed that mangiferin suppressed the nuclear translocation of NF-κB. However, the treatment of MM involves a combination of two or three drugs. In this study, we examined the effect of the combination of mangiferin and conventional anticancer drugs in an MM cell line. We showed that the combination of mangiferin and an anticancer drug decreased the viability of MM cell lines in comparison with each drug used separately. The decrease in the combination of mangiferin and an anticancer drug induced cell viability was attributed to increase the expression of p53 and Noxa and decreases the expression of XIAP, survivin, and Bcl-xL proteins via inhibition of NF-κB pathway. In addition, the combination treatment caused the induction of apoptosis, activation of caspase-3 and the accumulation of the cells in the sub-G1 phase of the cell cycle. Our findings suggest that the combination of mangiferin and an anticancer drug could be used as a new regime for the treatment of MM.
  • Tomoya Takeda; Masanobu Tsubaki; Toshiki Kino; Misa Yamagishi; Megumi Iida; Tatsuki Itoh; Motohiro Imano; Genzoh Tanabe; Osamu Muraoka; Takao Satou; Shozo Nishida
    Chemico-biological interactions 251 26 - 33 2016年05月 [査読有り]
     
    Mangiferin is a naturally occurring glucosyl xanthone, which induces apoptosis in various cancer cells. However, the molecular mechanism underlying mangiferin-induced apoptosis has not been clarified thus far. Therefore, we examined the molecular mechanism underlying mangiferin-induced apoptosis in multiple myeloma (MM) cell lines. We found that mangiferin decreased the viability of MM cell lines in a concentration-dependent manner. We also observed an increased number of apoptotic cells, caspase-3 activation, and a decrease in the mitochondrial membrane potential. In addition, mangiferin inhibited the nuclear translocation of nuclear factor kappa B (NF-κB) and expression of phosphorylated inhibitor kappa B (IκB) and increased the expression of IκB protein, whereas no changes were observed in the phosphorylation levels of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal protein kinase 1/2 (JNK1/2), and mammalian target of rapamycin (mTOR). The molecular mechanism responsible for mangiferin-induced inhibition of nuclear translocation of NF-κB was a decrease in the expression of phosphorylated NF-κB-inducing kinase (NIK). Moreover, mangiferin decreased the expression of X-linked inhibitor of apoptosis protein (XIAP), survivin, and Bcl-xL proteins. Knockdown of NIK expression showed results similar to those observed with mangiferin treatment. Our results suggest that mangiferin induces apoptosis through the inhibition of nuclear translocation of NF-κB by suppressing NIK activation in MM cell lines. Our results provide a new insight into the molecular mechanism of mangiferin-induced apoptosis. Importantly, since the number of reported NIK inhibitors is limited, mangiferin, which targets NIK, may be a potential anticancer agent for the treatment of MM.
  • Tsubaki M; Mashimo K; Takeda T; Kino T; Fujita A; Itoh T; Imano M; Sakaguchi K; Satou T; Nishida S
    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 78 23 - 29 2016年03月 [査読有り]
     
    Macrophage inflammatory protein-1alpha (MIP-1α) is detected at high concentrations in patients with multiple myeloma. It is thought to play an important role in the etiology of multiple myeloma and osteolysis. Thus, inhibiting MIP-1α expression may be useful in developing therapeutic treatments for multiple myeloma-induced osteolysis. In this study, we investigated the potential of statins to inhibit mRNA expression and secretion of MIP-1α in mouse myeloma cells (MOPC-31C). We found that statins inhibited the lipopolysaccharide (LPS)-induced MIP-1α mRNA expression and protein secretion in MOPC-31C cells. This inhibition was reversed when farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), intermediates of the mevalonate pathway, were combined with statins. Furthermore, statins reduced the GTP form of Ras, a phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2), and phosphorylated Akt. Our results indicate that statins inhibit biosynthesis of FPP and GGPP and thereby down regulate signal transduction of Ras/ERK and Ras/Akt pathways. The net effect suppresses LPS-induced MIP-1α mRNA expression and protein secretion in MOPC-31C cells. Thus, statins hold great promise for developing effective therapies against myeloma-induced osteolysis.
  • Masanobu Tsubaki; Tomoya Takeda; Tadahumi Tani; Hirotaka Shimaoka; Naohiro Suzuyama; Kotaro Sakamoto; Arisa Fujita; Naoki Ogawa; Tatsuki Itoh; Motohiro Imano; Yoshinori Funakami; Seiji Ichida; Takao Satou; Shozo Nishida
    INTERNATIONAL JOURNAL OF CANCER 137 1 243 - 250 2015年07月 [査読有り]
     
    Oxaliplatin is a key drug commonly used in colorectal cancer treatment. Despite high clinical efficacy, its therapeutic application is limited by common, dose-limiting occurrence of neuropathy. As usual symptomatic neuropathy treatments fail to improve the patients' condition, there is an urgent need to advance our understanding of the pathogenesis of neuropathy to propose effective therapy and ensure adequate pain management. Oxaliplatin-induced neuropathy was recently reported to be associated with protein kinase C (PKC) activation. It is unclear, however, whether PKC inhibition can prevent neuropathy. In our current studies, we found that a PKC inhibitor, tamoxifen, inhibited oxaliplatin-induced neuropathy via the PKC/extracellular signal-regulated kinase (ERK)/c-Fos pathway in lumbar spinal cords (lumbar segments 4-6). Additionally, tamoxifen was shown to act in synergy with oxaliplatin to inhibit growth in tumor cells-implanted mice. Moreover, mitogen-activated protein kinase kinase (MEK) 1/2 inhibitor, PD0325901, suppressed oxaliplatin-induced neuropathy and enhanced oxaliplatin efficacy. Our results indicate that oxaliplatin-induced neuropathy is associated with PKC/ERK/c-Fos pathway in lumbar spinal cord. Additionally, we demonstrate that disruption of this pathway by PKC and MEK inhibitors suppresses oxaliplatin-induced neuropathy, thereby suggesting that PKC and MEK inhibitors may be therapeutically useful in preventing oxaliplatin-induced neuropathy and could aid in combination antitumor pharmacotherapy.
  • Tsubaki M; Takeda T; Ogawa N; Sakamoto K; Shimaoka H; Fujita A; Itoh T; Imano M; Ishizaka T; Satou T; Nishida S
    Leukemia research 39 4 445 - 452 2015年04月 [査読有り]
     
    The acquisition of anti-cancer drug resistance is a major limitation of chemotherapy for multiple myeloma(MM) and it is thus important to identify the mechanisms by which MM cells develop such drug resistance. In a previous study, we showed that multidrug resistance (MDR) involves the overexpression of MDR1 and survivin in vincristine-resistant RPMI8226/VCR cells. However, the underlying mechanism of MDR remains unclear. In this study, we investigated the mechanism of MDR in RPMI8226/VCR cells, and found that RPMI8226/VCR cells exhibit increased levels of activated ERK1/2, Akt, and NF-kappa B, while the levels of activated mTOR, p38MAPK, and JNK do not differ between RPMI8226/VCR cells and their vincristine-susceptible counterparts. In addition, the inhibition of ERK1/2, Akt, or NF-kappa B by inhibitors reversed thedrug resistance of RPMI8226/VCR cells via the suppression of survivin expression, but did not affect MDR1 expression; RNA silencing of survivin expression completely reversed vincristine resistance, while MDR1 silencing only weakly suppressed vincristine resistance in RPMI8226/VCR cells. These results indicate that enhanced survivin expression via the activation of ERK1/2, Akt, and NF-kappa B plays a critical role in vincristine resistance in RPMI8226/VCR cells. Our findings suggest that ERK1/2, Akt, and NF-kappa B inhibitors are potentially useful as anti-MDR agents for the treatment of vincristine-resistant MM. (C) 2015 Elsevier Ltd. All rights reserved.
  • Masanobu Tsubaki; Tomoya Takeda; Toshiki Kino; Naoya Obata; Tatsuki Itoh; Motohiro Imano; Kenji Mashimo; Daichiro Fujiwara; Katsuhiko Sakaguchi; Takao Satou; Shozo Nishida
    American journal of cancer research 5 10 3186 - 97 2015年 [査読有り]
     
    Metastatic melanoma is a life-threatening disease for which no effective treatment is currently available. In melanoma cells, Rho overexpression promotes invasion and metastasis. However, the effect of statins on spontaneous metastasis and tumor growth remains unclear. In the present study, we investigated the mechanism of statin-mediated tumor growth and metastasis inhibition in an in vivo model. We found that statins significantly inhibited spontaneous metastasis and tumor growth. Statins inhibited the mRNA expression and enzymatic activities of matrix metalloproteinases (MMPs) in vivo and also suppressed the mRNA and protein expression of very late antigens (VLAs). Moreover, statins inhibited the prenylation of Rho as well as the phosphorylation of LIM kinase, serum response factor (SRF), and c-Fos downstream of the Rho signaling pathway. In addition, statins enhanced p53, p21, and p27 expression and reduced phosphorylation of cyclin-dependent kinase and expression of cyclin D1 and E2. These results indicate that statins suppress Rho signaling pathways, thereby inhibiting tumor metastasis and growth. Furthermore, statins markedly improved the survival rate in a metastasis model, suggesting that statins have potential clinical applications for the treatment of metastatic cancers.
  • Tsubaki M; Takeda T; Kino T; Itoh T; Imano M; Tanabe G; Muraoka O; Satou T; Nishida S
    American journal of translational research 7 8 1371 - 81 2015年 [査読有り]
     
    Rheumatoid arthritis is a systemic autoimmune disease characterized by chronic inflammation of synovial joints, ultimately leading to a progressive and irreversible joint destruction. Activation of nuclear factor-kappa B (NF-κB) promotes production of proinflammatory cytokines in various inflammatory diseases including rheumatoid arthritis. Mangiferin, 1,3,6,7-tetrahydroxyxanthone-C2-β-D-glucoside (C-glucosyl xanthone), is a naturally occurring polyphenol. Our previous results showed that mangiferin suppressed NF-κB activation. However, it is unclear, whether mangiferin can prevent rheumatoid arthritis through suppression of NF-κB activation and expression of various cytokines, such as tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6), which play a critical role in the pathogenesis of rheumatoid arthritis. In the present study, we found that mangiferin suppressed the progression and incidence of CIA in DBA1/J mice. In CIA mice, mangiferin inhibited the mRNA expression of cytokine genes in thymus and spleen of CIA mie and led to decreased serum levels of IL-1β, IL-6, TNF-α, and receptor activator NF-κB ligand (RANKL) via inhibition of NF-κB and activation of extracellular signal-regulated kinase 1/2 (ERK1/2). In addition, mangiferin markedly inhibited not only developing but also clinically evident CIA. These findings suggest that mangiferin has potential clinical applications for the treatment of rheumatoid arthritis.
  • Tsubaki M; Takeda T; Sakamoto K; Shimaoka H; Fujita A; Itoh T; Imano M; Mashimo K; Fujiwara D; Sakaguchi K; Satou T; Nishida S
    American journal of cancer research 5 1 168 - 179 2015年 [査読有り]
     
    Osteolytic bone disease in multiple myeloma (MM) is associated with upregulated osteoclast activity. Macrophage inflammatory protein-1 alpha (MIP-1 alpha) is crucially involved in the development of osteolytic bone lesions in MM. We previously reported that minodronate inhibited lipopolysaccharide-induced MIP-1 alpha secretion in mouse myeloma cells. However, it remains unknown whether bisphosphonates and statins inhibit MIP-1 alpha secretion by human MM cells. In present study, we investigated whether bisphosphonates and statins had any inhibitory effect on MIP-1 alpha secretion by human myeloma cells and the mechanism underlying this effect. In this study, we found that bisphosphonates and statins inhibited MIP-1 alpha mRNA and MIP-1 alpha secretion and suppressed extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt phosphorylation by inhibiting Ras prenylation. Moreover, bisphosphonates and statins suppressed the expression of acute myeloid leukemia-1 alpha (AML-1A) mRNA, a MIP-1 alpha transcription factor. These results indicate that bisphosphonates and statins suppress the Ras/mitogen-activated protein kinase kinase/ERK/AML-1A and Ras/phosphatidylinositol-3 kinase/Akt/AML-1A pathways, thereby inhibiting MIP-1 alpha secretion by MM cells. Therefore, use of MIP-1 alpha expression inhibitors such as bisphosphonates and statins may provide a new therapeutic approach to inhibiting tumour progression and bone destruction in MM patients.
  • Tsubaki M; Ogawa N; Takeda T; Sakamoto K; Shimaoka H; Fujita A; Itoh T; Imano M; Satou T; Nishida S
    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 68 8 999 - 1005 2014年10月 [査読有り]
     
    Dimethyl fumarate (DMF) is a fumaric acid ester that is used to treat psoriasis and multiple sclerosis. Recently, DMF was found to exhibit anti-tumor effects. However, the molecular mechanisms underlying these effects have not been elucidated. In this study, we investigated the mechanism of DMF-induced apoptosis in different human hematopoietic tumor cell lines. We found that DMF induced apoptosis in different human hematopoietic tumor cell lines but it did not affect the normal human B lymphocyte cell line RPMI 1788. We also observed a concurrent increase in caspase-3 activity and in the number of Annexin-V-positive cells. Furthermore, an examination of the survival signals, which are activated by apoptotic stimuli, revealed that DMF significantly inhibited nuclear factor-kappa B (NF-kappa B) p65 nuclear translocation. In addition, DMF suppressed B-cell lymphoma extra-large (Bcl-xL) and X-linked inhibitor of apoptosis (XIAP) expression whereas Bcl-2, survivin, Bcl-2-associated X protein (Bax), and Bim levels did not change. These results indicated that DMF induced apoptosis by suppressing NF-kappa B activation, and Bcl-xL and XIAP expression. These findings suggested that DMF might have potential as an anticancer agent that could be used in combination therapy with other anticancer drugs for the treatment of human hematopoietic tumors. (C) 2014 Elsevier Masson SAS. All rights reserved.
  • Masanobu Tsubaki; Makiko Komai; Tatsuki Itoh; Motohiro Imano; Kotaro Sakamoto; Hirotaka Shimaoka; Tomoya Takeda; Naoki Ogawa; Kenji Mashimo; Daiichiro Fujiwara; Junji Mukai; Katsuhiko Sakaguchi; Takao Satou; Shozo Nishida
    JOURNAL OF BIOMEDICAL SCIENCE 21 10  2014年02月 [査読有り]
     
    Background: Bisphosphonates are an important class of antiresorptive drugs used in the treatment of metabolic bone diseases. Recent studies have shown that nitrogen-containing bisphosphonates induced apoptosis in rabbit osteoclasts and prevented prenylated small GTPase. However, whether bisphosphonates inhibit osteoclast formation has not been determined. In the present study, we investigated the inhibitory effect of minodronate and alendronate on the osteoclast formation and clarified the mechanism involved in a mouse macrophage-like cell lines C7 and RAW264.7. Results: It was found that minodronate and alendronate inhibited the osteoclast formation of C7 cells induced by receptor activator of NF kB ligand and macrophage colony stimulating factor, which are inhibited by the suppression of geranylgeranyl pyrophosphate (GGPP) biosynthesis. It was also found that minodronate and alendronate inhibited the osteoclast formation of RAW264.7 cells induced by receptor activator of NF-kappa B ligand. Furthermore, minodronate and alendornate decreased phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt; similarly, U0126, a mitogen protein kinase kinase 1/2 (MEK1/2) inhibitor, and LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor, inhibited osteoclast formation. Conclusions: This indicates that minodronate and alendronate inhibit GGPP biosynthesis in the mevalonate pathway and then signal transduction in the MEK/ERK and PI3K/Akt pathways, thereby inhibiting osteoclast formation. These results suggest a novel effect of bisphosphonates that could be effective in the treatment of bone metabolic diseases, such as osteoporosis.
  • Masanobu Tsubaki; Makiko Komai; Tatsuki Itoh; Motohiro Imano; Kotaro Sakamoto; Hirotaka Shimaoka; Tomoya Takeda; Naoki Ogawa; Kenji Mashimo; Daiichiro Fujiwara; Junji Mukai; Katsuhiko Sakaguchi; Takao Satou; Shozo Nishida
    LEUKEMIA RESEARCH 38 1 121 - 130 2014年01月 [査読有り]
     
    The calcium channel blocker verapamil inhibits the transport function of multidrug resistance protein 1 (MDR1). Although verapamil acts to reverse MDR in cancer cells, the underlying mechanism remains unclear. In the present study, we investigated the mechanism of reversing MDR by verapamil in anticancer drug-resistant multiple myeloma (MM) cell lines. We found that verapamil suppresses MDR1 and survivin expressions and increases Bim expression via suppression of Src activation. Furthermore, dasatinib reversed the drug-resistance of the drug-resistant cell lines. These findings suggest that Src inhibitors are potentially useful as an anti-MDR agent for the treatment of malignant tumor cells. (C) 2013 Elsevier Ltd. All rights reserved.
  • Masanobu Tsubaki; Makiko Komai; Tatsuki Itoh; Motohiro Imano; Kotaro Sakamoto; Hirotaka Shimaoka; Naoki Ogawa; Kenji Mashimo; Daichiro Fujiwara; Tomoya Takeda; Junji Mukai; Katsuhiko Sakaguchi; Takao Satou; Shozo Nishida
    EUROPEAN JOURNAL OF CANCER 49 17 3708 - 3717 2013年11月 [査読有り]
     
    Several autocrine soluble factors, including macrophage inflammatory protein-1 alpha and tumour necrosis factor-alpha (TNF-alpha), promote the survival and growth of multiple myeloma (MM) cells. We hypothesised that inhibition of the TNF-alpha autocrine loop may enhance the cytotoxic effect of anticancer drugs in MM cell lines. In the present study, a TNF-alpha-neutralizing antibody suppressed cell proliferation and enhanced the cytotoxic effect of anticancer drugs onMMcells. In addition, combination treatment with the TNF-alpha-neutralizing antibody and the chemotherapy agent melphalan inhibited nuclear factor kappa B (NF-kappa B) p65 nuclear translocation and mammalian target of rapamycin (mTOR) activation and upregulated the expression of Bax and Bim. Treatment of ARH-77 cells with the NF-kappa B inhibitor dimethyl fumarate or the mTOR inhibitor rapamycin suppressed NF-kappa B p65 nuclear translocation and enhanced the cytotoxic effect of melphalan. Furthermore, infliximab, a monoclonal antibody against TNF-alpha, also enhanced the cytotoxic effect of anticancer drugs in ARH-77 cells. These results indicated that TNF-alpha-neutralizing antibodies or infliximab enhanced the cytotoxic effect of anticancer drugs by suppressing the TNF receptor/mTOR/NF-kappa B pathways. The inhibition of TNF-alpha may thus provide a new therapeutic approach to control tumour progression and bone destruction in MM patients. (C) 2013 Elsevier Ltd. All rights reserved.
  • Tsubaki M; Komai M; Fujimoto S; Itoh T; Imano M; Sakamoto K; Shimaoka H; Takeda T; Ogawa N; Mashimo K; Fujiwara D; Mukai J; Sakaguchi K; Satou T; Nishida S
    Journal of experimental & clinical cancer research : CR 32 62 - 62 1 2013年09月 [査読有り]
     
    BACKGROUND: Increased motility and invasiveness of cancer cells are reminiscent of the epithelial-mesenchymal transition (EMT), which occurs during cancer progression and metastasis. Recent studies have indicated the expression of receptor activator of nuclear factor-κB (RANK) in various solid tumors, including breast cancer. Although activation of the RANK ligand (RANKL)/RANK system promotes cell migration, metastasis, and anchorage-independent growth of tumor-initiating cells, it remains to be investigated if RANKL induces EMT in breast cancer cells. In this study, we investigated whether RANKL induces EMT in normal breast mammary epithelial cells and breast cancer cells, and the mechanism underlying such induction. METHODS: Expression levels of vimentin, N-cadherin, E-cadherin, Snail, Slug, and Twist were examined by real-time polymerase chain reaction. Cell migration and invasion were assessed using Boyden chamber and invasion assays, respectively. The effects of RANKL on signal transduction molecules were determined by western blot analyses. RESULTS: We found that stimulation by RANKL altered the cell morphology to the mesenchymal phenotype in normal breast epithelial and breast cancer cells. In addition, RANKL increased the expression levels of vimentin, N-cadherin, Snail, and Twist and decreased the expression of E-cadherin. We also found that RANKL activated nuclear factor-κB (NF-κB), but not extracellular signal-regulated kinase 1/2, Akt, mammalian target of rapamycin, c-Jun N-terminal kinase, and signal transducer and activator of transcription 3. Moreover, dimethyl fumarate, a NF-κB inhibitor, inhibited RANKL-induced EMT, cell migration, and invasion, and upregulated the expressions of Snail, Twist, vimentin, and N-cadherin. CONCLUSIONS: The results indicate that RANKL induces EMT by activating the NF-κB pathway and enhancing Snail and Twist expression. These findings suggest that the RANKL/RANK system promotes tumor cell migration, invasion, and metastasis via the induction of EMT.
  • Shinsuke Nozaki; Tomoya Takeda; Takuya Kitaura; Nobuyuki Takenaka; Tohru Kataoka; Takaya Satoh
    Cellular Signalling 25 6 1361 - 1371 2013年06月 [査読有り]
     
    The small GTPase Rac1 plays a pivotal role in insulin-stimulated glucose uptake in skeletal muscle, which is mediated by GLUT4 translocation to the plasma membrane. However, regulatory mechanisms for Rac1 and its role in the signaling pathway composed of phosphoinositide 3-kinase and the serine/threonine kinase Akt remain obscure. Here, we investigate the role of Akt in the regulation of Rac1 in myocytes. Insulin-induced, but not constitutively activated Rac1-induced, GLUT4 translocation was suppressed by Akt inhibitor IV. Insulin-induced Rac1 activation, on the other hand, was completely inhibited by this inhibitor. Constitutively activated phosphoinositide 3-kinase induced Rac1 activation and GLUT4 translocation. This GLUT4 translocation was almost completely suppressed by Rac1 knockdown. Furthermore, constitutively activated phosphoinositide 3-kinase-induced, but not constitutively activated Rac1-induced, GLUT4 translocation was suppressed by Akt2 knockdown. Finally, insulin-induced Rac1 activation was indeed inhibited by Akt2 knockdown. Together, these results reveal a novel regulatory mechanism involving Akt2 for insulin-dependent Rac1 activation. © 2013 Elsevier Inc.
  • Shuji Ueda; Sohei Kitazawa; Kota Ishida; Yuki Nishikawa; Megumi Matsui; Hikaru Matsumoto; Takuji Aoki; Shinsuke Nozaki; Tomoya Takeda; Yoshikazu Tamori; Atsu Aiba; C. Ronald Kahn; Tohru Kataoka; Takaya Satoh
    FASEB JOURNAL 24 7 2254 - 2261 2010年07月 [査読有り]
     
    The Rho family GTPase Rac1 has been implicated in the regulation of glucose uptake in myoblast cell lines. However, no evidence for the role of Rac1 has been provided by a mouse model. The purpose of this study is to test the involvement of Rac1 in insulin action in mouse skeletal muscle. Intravenous administration of insulin indeed elicited Rac1 activation in gastrocnemius muscle, suggesting the involvement of Rac1 in this signaling pathway. We then examined whether insulin-stimulated translocation of the facilitative glucose transporter GLUT4 from its storage sites to the skeletal muscle sarcolemma depends on Rac1. We show that ectopic expression of constitutively activated Rac1, as well as intravenous administration of insulin, caused translocation of GLUT4 to the gastrocnemius muscle sarcolemma, as revealed by immunofluorescent staining of a transiently expressed exofacial epitope-tagged GLUT4 reporter. Of particular note, insulin-dependent, but not constitutively activated Rac1-induced, GLUT4 translocation was markedly suppressed in skeletal muscle-specific rac1-knockout mice compared to control mice. Immunogold electron microscopic analysis of endogenous GLUT4 gave similar results. Collectively, we propose a critical role of Rac1 in insulin-dependent GLUT4 translocation to the skeletal muscle sarcolemma, which has heretofore been predicted solely by cell culture studies.-Ueda, S., Kitazawa, S., Ishida, K., Nishikawa, Y., Matsui, M., Matsumoto, H., Aoki, T., Nozaki, S., Takeda, T., Tamori, Y., Aiba, A., Kahn, C. R., Kataoka, T., Satoh, T. Crucial role of the small GTPase Rac1 in insulin-stimulated translocation of glucose transporter 4 to the mouse skeletal muscle sarcolemma. FASEB J. 24, 2254-2261 (2010). www.fasebj.org

講演・口頭発表等

  • Mechanism of tamoxifen acquired resistance via EMT induction by EGFR activation in breast cancer cells
    Tomoya Takeda; Masanobu Tsubaki; Remi Tanaka; Koudai Takimoto; Shozo Nishida
    The 82th Annual Meeting of the Japanese Cancer Association 2023年
  • EGFR 活性化による EMT 誘導を介したタモキシフェン耐性獲得機序
    武田 朋也; 椿 正寛; 田中 澪美; 滝本 航大; 西田 升三
    第27回日本がん分子標的治療学会学術集会 2023年
  • AT9283 exhibits antiproliferative effect on BCR-ABL TKI sensitive and resistant CML cells by inhibition of Aurora.
    Tomoya Takeda; Masanobu Tsubaki; Takuya Matsuda; Kana Kishimoto; Remi Tanaka; Shozo Nishida
    The 81th Annual Meeting of the Japanese Cancer Association 2022年
  • AT9283はBCR-ABL阻害剤感受性および抵抗性の慢性骨髄性白血病細胞でのAurora AおよびAurora B阻害を介したアポトーシス誘導効果.
    武田 朋也; 椿 正寛; 松田 拓弥; 岸本 佳奈; 田中 澪美; 西田 升三
    第26回日本がん分子標的治療学会学術集会 2022年
  • AT9283 suppresses proliferation in tyrosine kinase inhibitor sensitive and resistant chronic myeloid leukemia cells by inhibition of Aurora A and Aurora B.
    Tomoya Takeda; Masanobu Tsubaki; Shozo Nishida
    The 5rd International Cancer Research Symposium of Training Plan for Oncology Professionals 2022年
  • AT9283 induces apoptosis via inhibition of Aurora kinase in imatinib sensitive and resistance CML cells.
    Tomoya Takeda; Masanobu Tsubaki; Takuya Matsuda; Yuuta Yamamoto; Kana Kishimoto; Shozo Nishida
    The 80th Annual Meeting of the Japanese Cancer Association 2021年
  • AT9283 によるイマチニブ感受性及び耐性慢性骨髄性白血病細胞における Aurora A 及び Aurora B 阻害を介した細胞死誘導効果
    武田 朋也; 椿 正寛; 松田 拓弥; 山本 裕太; 岸本 佳奈; 森井 悠介; 西田 升三
    第25回日本がん分子標的治療学会学術集会 2021年 口頭発表(一般)
  • Dimethyl fumarate suppresses tumor growth and metastasis of metastatic melanoma by inhibiting the nuclear translocation of NF-κB.
    Tomoya Takeda; Masanobu Tsubaki; Shozo Nishida
    The 4rd International Cancer Research Symposium of Training Plan for Oncology Professionals 2021年 ポスター発表
  • Sorafenibによるマルチキナーゼ阻害での悪性黒色腫での腫瘍増殖・転移抑制効果
    武田朋也; 椿正寛; 源野秀次; 山本裕太; 西田升三
    第24回日本がん分子標的治療学会学術集会 2020年 ポスター発表
  • Sorafenib inhibits the tumor growth and metastasis through suppression of receptor tyrosine kinase pathway in melanoma.
    Tomoya Takeda; Masanobu Tsubaki; Shuji Genno; Shozo Nishida
    The 79th Annual Meeting of the Japanese Cancer Association 2020年 口頭発表(一般)
  • Sorafenib targeting of c-Kit aberration in metastatic melanoma.
    Tomoya Takeda; Masanobu Tsubaki; Shozo Nishida
    The 3rd International Cancer Research Symposium of Training Plan for Oncology Professionals 2020年 ポスター発表
  • Sorafenib suppresses the tumor growth and metastasis of melanoma through suppression of receptor tyrosine kinase pathway.
    Tomoya Takeda; Masanobu Tsubaki; Minami Jinushi; Shuji Genno; Shozo Nishida
    The 78th Annual Meeting of the Japanese Cancer Association 2019年 ポスター発表
  • Sorafenibによる受容体チロシンキナーゼ阻害を介した悪性黒色腫での腫瘍増殖・転移抑制効果
    武田朋也; 椿正寛; 地主みなみ; 源野秀次; 西田升三
    第23回日本がん分子標的治療学会学術集会 2019年 口頭発表(一般)
  • Dimethyl fumarate によるNF-κB 阻害を介した悪性黒色腫での抗腫瘍効果
    武田朋也; 椿正寛; 浅野良太; 川島啓司; 西田升三
    第68回日本薬学会近畿支部総会・大会 2018年 口頭発表(一般)
  • Dimethyl fumarate suppresses the tumor growth and metastasis through suppression of NF-kappaB.  [通常講演]
    Tomoya Takeda; Masanobu Tsubaki; Ryota Asano; Keishi Kawashima; Mitsuki Tabata; Shozo Nishida
    The 77th Annual Meeting of the Japanese Cancer Association 2018年
  • Dimethyl fumarate によるNF-κB 阻害を介した悪性黒色腫での抗腫瘍効果.  [通常講演]
    武田朋也; 椿正寛; 浅野良太; 川島啓司; 西田升三
    第68回日本薬学会近畿支部総会・大会 2018年
  • Dimethyl fumarateによるNF-κB核移行阻害を介した悪性黒色腫での腫瘍増殖・転移抑制効果.  [通常講演]
    武田朋也; 椿正寛; 浅野良太; 川島啓司; 田畑光希; 西田升三
    第22回日本がん分子標的治療学会学術集会 2018年
  • Dimethyl fumarateによる悪性黒色腫でのNF-κB阻害を介した腫瘍増殖・転移抑制効果.  [通常講演]
    武田 朋也; 椿 正寛; 浅野 良太; 川島 啓司; 西田 升三
    日本薬学会第138回年会 2018年
  • MangiferinによるNIK/NF-kappaB経路阻害を介した腫瘍増殖・転移抑制効果.  [通常講演]
    武田 朋也; 椿 正寛; 友成 佳加; 河本 雄一; 浅野 良太; 川島 啓司; 藤本 伸一郎; 山添 譲; 西田 升三
    第21回日本がん分子標的治療学会学術集会 2017年
  • 新規NIK阻害剤mangiferin投与による腫瘍増殖・転移抑制効果.  [通常講演]
    武田 朋也; 椿 正寛; 友成 佳加; 藤本 伸一郎; 山添 譲; 西田 升三
    日本薬学会第137回年会 2017年
  • Mangiferin, a novel NIK inhibitor, inhibition metasatsis and tumor growth in mouse melanoma model.  [通常講演]
    Tomoya Takeda; Masanobu Tsubaki; Ryo-ta Asano; Keishi Kawashima; Shozo Nishida
    The 76th Annual Meeting of the Japanese Cancer Association 2017年
  • Mangiferin によるNF-κB 経路阻害を介した腫瘍増殖・転移抑制効果.  [通常講演]
    武田 朋也; 椿 正寛; 浅野 良太; 川島 啓司; 西田升三
    第67回日本薬学会近畿支部総会・大会 2017年
  • 新規NIK阻害剤mangiferin による腫瘍増殖・転移抑制効果.  [通常講演]
    武田 朋也; 椿 正寛; 木野 稔己; 友成 佳加; 西田 升三
    第66回日本薬学会近畿支部総会・大会 2016年
  • 新規NIK阻害薬によるNF-kappaB 経路抑制を介したアポトーシス誘導機序.  [通常講演]
    武田 朋也; 椿 正寛; 木野 稔己; 友成 佳加; 眞下 恵次; 阪口 勝彦; 西田 升三
    第75回日本癌学会学術総会 2016年
  • 多発性骨髄腫における新規NIK阻害剤mangiferinによる細胞死誘導機構の解析.  [通常講演]
    武田 朋也; 椿 正寛; 木野 稔己; 友成 佳加; 眞下 恵次; 藤原 大一朗; 阪口 勝彦; 西田 升三
    第20回日本がん分子標的治療学会 2016年
  • NIK阻害剤による多発性骨髄腫の細胞死誘導効果及びその作用機序の解明.  [通常講演]
    武田 朋也; 椿 正寛; 木野 稔己; 眞下 恵次; 山添 譲; 阪口 勝彦; 西田 升三
    日本薬学会第136回年会 2016年
  • Bisphospohnates 及びstatins による多発性骨髄腫でのMIP-1α分泌抑制効果―ドラッグリポジショニングによる骨破壊因子抑制剤の開発―.  [通常講演]
    武田 朋也; 椿 正寛; 木野 稔己; 西田 升三
    第65回日本薬学会近畿支部総会・大会 2015年
  • Bisphosphonates 及びstatins による骨髄腫でのRas 経路阻害を介したMIP-1alpha 発現抑制効果.  [通常講演]
    武田 朋也; 椿 正寛; 木野 稔己; 眞下 恵次; 藤原 大一朗; 阪口 勝彦; 西田 升三
    第74回日本癌学会学術総会 2015年
  • Bisphosphonates 及び statinsによる骨髄腫でのMIP-1α分泌抑制効果-ドラッグリポジショニングによる骨破壊因子抑制剤の開発-.  [通常講演]
    武田 朋也; 椿 正寛; 藤田 亜梨沙; 木野 稔己; 中橋 拓也; 眞下 恵次; 藤原 大一郎; 山添 譲; 阪口 勝彦; 西田 升三
    第19回日本がん分子標的治療学会 2015年
  • RANKL/RANK システムによるNF-κB活性化を介したEMT誘導に基づく浸潤促進効果.  [通常講演]
    武田 朋也; 椿 正寛; 嶌岡 弘高; 坂本 洸太郎; 藤田 亜梨沙; 小川 直希; 眞下 恵次; 藤原 大一郎; 山添 譲; 阪口 勝彦; 石坂 敏彦; 西田 升三
    日本薬学会第135回年会 2015年
  • RANKL によるEMT 誘導に基づく浸潤促進効果.  [通常講演]
    武田 朋也; 椿 正寛; 嶌岡 弘高; 坂本 洸太郎; 藤田 亜梨沙; 西田 升三
    第64回日本薬学会近畿支部総会・大会 2014年
  • RANKL/RANK システムによる乳がんでのNF-kappaB 活性化を介したEMT 促進効果.  [通常講演]
    武田 朋也; 椿 正寛; 嶌岡 弘高; 坂本 洸太郎; 藤田 亜梨沙; 小川 直希; 山添 譲; 向井 淳治; 西田 升三
    第73回日本癌学会学術総会 2014年

MISC

産業財産権

  • 特許第6488264号:NIK阻害剤    2019年03月01日
    西田升三, 椿正寛, 武田朋也
  • 西田 升三, 椿 正寛, 武田 朋也, 西尾 和人, 中山 隆志, 坂井 和子, 駒居 真紀子, 小野 優里, 深松 真衣  学校法人近畿大学  201603011480948052

共同研究・競争的資金等の研究課題

  • 日本学術振興会:科学研究費助成事業
    研究期間 : 2023年04月 -2026年03月 
    代表者 : 武田 朋也
  • 骨微小環境を標的としたトリプルネガティブ乳癌の骨転移治療薬の開発
    一般財団法人横山臨床薬理研究助成基金:
    研究期間 : 2023年07月 -2024年06月
  • 日本学術振興会:科学研究費助成事業 若手研究
    研究期間 : 2020年04月 -2022年03月 
    代表者 : 武田 朋也
     
    トリプルネガティブ乳癌(TNBC;Triple negative breast cancer)の骨転移成立には、TNBCと骨髄間質細胞との相互作用が重要である。本研究では、TNBCと骨髄間質細胞との相互作用に関与する因子としてケモカイン受容体CXCR4を見出した。さらに、CXCR4を阻害することでTNBCの骨転移を抑制することを明らかにした。以上より、CXCR4が骨髄間質細胞と相互作用することで、TNBCの骨転移を亢進している可能性が示唆された。そして、CXCR4を阻害する薬剤がTNBCの骨転移を抑制する新たな治療薬となる可能性が期待される。
  • 日本学術振興会:科学研究費助成事業 若手研究(B)
    研究期間 : 2017年04月 -2020年03月 
    代表者 : 武田 朋也
     
    乳癌の予後不良となる最大の原因として、転移が挙げられる。転移には、乳癌(上皮細胞)が間葉系の乳がん細胞に変化し、浸潤・運動を亢進する上皮間葉転換(EMT)が重要な役割を担う。本研究では乳癌におけるEMTの分子メカニズムについて検討した。その結果、Zeb-1が乳癌のEMT誘導に関与し、Zeb-1を阻害することで、乳癌の転移が抑制された。このことから、乳癌の転移におけるZeb-1の重要性が明らかとなり、乳癌の転移を抑制する新たな治療標的分子となり得る可能性が示唆された。
  • 日本学術振興会:科学研究費助成事業 基盤研究(C)
    研究期間 : 2015年04月 -2018年03月 
    代表者 : 西田 升三; 椿 正寛; 武田 朋也
     
    ヒト慢性骨髄性白血病細胞においてイマチニブ耐性株を樹立し、耐性獲得機序の解析を行い、MET活性化に基づくバイパスシグナル伝達経路が関与することを見出した。さらに、METを阻害する分子標的薬によりイマチニブ耐性を克服することを明らかにした。以上の結果は、臨床におけるイマチニブ耐性慢性骨髄性白血病出現時における治療に貢献できる可能性が考えられる。 なお、本研究成果は主な発表論文の項に全てまとめてある。

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