KINDAI UNIVERSITY


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FUKUSHIMA Nobuyuki

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FacultyDepartment of Life Science / Graduate School of Science and Engineering Research
PositionProfessor
Degree
Commentator Guidehttps://www.kindai.ac.jp/meikan/656-fukushima-nobuyuki.html
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Last Updated :2020/07/08

Research Activities

Research Areas

  • Life sciences, Pharmacology
  • Life sciences, Pharmaceuticals - health and biochemistry
  • Life sciences, Developmental biology
  • Life sciences, Cell biology
  • Life sciences, Neuroscience - general

Published Papers

  • Involvement of LPA signaling via LPA receptor-2 in the promotion of malignant properties in osteosarcoma cells., Takahashi K, Fukushima K, Tanaka K, Minami K, Ishimoto K, Otagaki S, Fukushima N, Honoki K, Tsujiuchi T, Experimental cell research, Experimental cell research, 369(2), 316 - 324, Aug. 2018 , Refereed
  • Involvement of FFA1 and FFA4 in the regulation of cellular functions during tumor progression in colon cancer cells., Takahashi K, Fukushima K, Onishi Y, Minami K, Otagaki S, Ishimoto K, Fukushima N, Honoki K, Tsujiuchi T, Experimental cell research, Experimental cell research, 369(1), 54 - 60, Aug. 2018 , Refereed
  • Lysophosphatidic acid receptor-2 (LPA2) and LPA5 regulate cellular functions during tumor progression in fibrosarcoma HT1080 cells., Takahashi K, Minami K, Otagaki S, Ishimoto K, Fukushima K, Fukushima N, Honoki K, Tsujiuchi T, Biochemical and biophysical research communications, Biochemical and biophysical research communications, Aug. 2018 , Refereed
  • Induction of GPR40 positively regulates cell motile and growth activities in breast cancer MCF-7 cells., Fukushima K, Takahashi K, Kusaka M, Ishimoto K, Minami K, Otagaki S, Fukushima N, Honoki K, Tsujiuchi T, Journal of receptor and signal transduction research, Journal of receptor and signal transduction research, 1 - 5, Aug. 2018 , Refereed
  • Promotion of cell-invasive activity through the induction of LPA receptor-1 in pancreatic cancer cells., Fukushima K, Otagaki S, Takahashi K, Minami K, Ishimoto K, Fukushima N, Honoki K, Tsujiuchi T, Journal of receptor and signal transduction research, Journal of receptor and signal transduction research, 38(4), 367 - 371, Aug. 2018 , Refereed
  • Exposure to bisphenol A affects GABAergic neuron differentiation in neurosphere cultures., Fukushima N, Nagao T, Neuroreport, Neuroreport, 29(9), 712 - 717, Jun. 2018 , Refereed
  • Effects of LPA1 and LPA6 on the regulation of colony formation activity in colon cancer cells treated with anticancer drugs., Takahashi K, Fukushima K, Otagaki S, Ishimoto K, Minami K, Fukushima N, Honoki K, Tsujiuchi T, Journal of receptor and signal transduction research, Journal of receptor and signal transduction research, 38(1), 71 - 75, Feb. 2018 , Refereed
  • Involvement of LPA receptor-5 in the enhancement of cell motile activity by phorbol ester and anticancer drug treatments in melanoma A375 cells., Fukushima K, Takahashi K, Kurokawa A, Ishimoto K, Otagaki S, Minami K, Fukushima N, Honoki K, Tsujiuchi T, Biochemical and biophysical research communications, Biochemical and biophysical research communications, 496(1), 225 - 230, Jan. 2018 , Refereed
  • Different effects of GPR120 and GPR40 on cellular functions stimulated by 12-O-tetradecanoylphorbol-13- acetate in melanoma cells., FUKUSHIMA Nobuyuki, 475, 25 - 30, Jul. 2016 , Refereed
  • Downregulation of activation factors of endothelia and fibroblasts via lysophosphatidic acid signaling in a mouse lung cancer LL/2 cell line., Tanabe E, Kitayoshi M, Hirane M, Araki M, Dong Y, Fukushima N, Tsujiuchi T, Journal of receptor and signal transduction research, Journal of receptor and signal transduction research, 33(5), 286 - 290, Oct. 2013 , Refereed
  • Extracellular lipid metabolism influences the survival of ovarian cancer cells., Kuwata S, Ohkubo K, Kumamoto S, Yamaguchi N, Izuka N, Murota K, Tsujiuchi T, Iwamori M, Fukushima N, Biochemical and biophysical research communications, Biochemical and biophysical research communications, 439(2), 280 - 284, Sep. 2013 , Refereed
  • Extracellular lipid metabolism influences the survival of ovarian cancer cells, Biochem. Biophys. Res. Commun., Biochem. Biophys. Res. Commun., Aug. 2013
  • Hydrogen peroxide stimulates cell motile activity through LPA receptor-3 in liver epithelial WB-F344 cells., Shibata A, Tanabe E, Inoue S, Kitayoshi M, Okimoto S, Hirane M, Araki M, Fukushima N, Tsujiuchi T, Biochemical and biophysical research communications, Biochemical and biophysical research communications, 433(3), 317 - 321, Apr. 2013 , Refereed
  • Enhancement of Drug Resistance by Lysophosphatidic Acid Receptor-3 in Mouse Mammary Tumor FM3A Cells., Fukui R, Kato K, Okabe K, Kitayoshi M, Tanabe E, Fukushima N, Tsujiuchi T, Journal of toxicologic pathology, Journal of toxicologic pathology, 25(3), 225 - 228, Sep. 2012 , Refereed
  • Different effects on cell proliferation and migration abilities of endothelial cells by LPA(1) and LPA(3) in mammary tumor FM3A cells, Misaho Kitayoshi, Rie Fukui, Eriko Tanabe, Kohei Kato, Kyohei Yoshikawa, Nobuyuki Fukushima, Toshifumi Tsujiuchi, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, 32(4), 209 - 213, Aug. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) receptors belong to G protein-coupled transmembrane receptors and mediate a variety of cellular responses through the binding of LPA. So far, six types of LPA receptors (LPA receptor-1 (LPA(1)) to LPA(6)) have been identified. Recently, it has been demonstrated that each LPA receptor has opposite effects on malignant property of cancer cells. In this study, to evaluate an involvement of LPA receptors on angiogenic process in mammary tumor cells, we generated Lpar1- and Lpar3-expressing (FM3A-a1 and FM3A-a3A9, respectively) cells from FM3A cells, and investigated the effects on cell proliferation and migration abilities of endothelial F-2 cells by those cells. In Vegf-A and Vegf-C genes, FM3A-a1 cells indicated high expression and FM3A-a3A9 cells showed low expression, compared with control cells. When F-2 cells were cultured with a supernatant from FM3A-a1 cells, the cell growth rate and migration ability of F-2 cells was significantly higher than control cells. By contrast, a supernatant from FM3A-a3A9 cells significantly inhibited those abilities of F-2 cells. These results suggest that LPA(1) and LPA(3) may play opposite roles on the regulation of endothelial cells in mouse mammary tumor FM3A cells.
  • Genetic and epigenetic alterations of lysophosphatidic Acid receptor genes in rodent tumors by experimental models., Tsujiuchi T, Okabe K, Fukushima N, Journal of toxicologic pathology, Journal of toxicologic pathology, 24(3), 143 - 148, Sep. 2011 , Refereed
  • No Involvement of Lysophosphatidic Acid Receptor-3 in Cell Migration of Mouse Lung Tumor Cells Stimulatedby 12-O-Tetradecanoylphorbol-13-acetate., Okumura M, Kato K, Fukui R, Fukushima N, Tsujiuchi T, Journal of toxicologic pathology, Journal of toxicologic pathology, 24(3), 183 - 186, Sep. 2011 , Refereed
  • Polyunsaturated fatty acids induce ovarian cancer cell death through ROS-dependent MAP kinase activation, Aiko Tanaka, Akane Yamamoto, Kaeko Murota, Toshifumi Tsujiuchi, Masao Iwamori, Nobuyuki Fukushima, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 493(1), 468 - 473, Nov. 2017 , Refereed
    Summary:Free fatty acids not only play a role in cell membrane construction and energy production but also exert diverse cellular effects through receptor and non-receptor mechanisms. Moreover, epidemiological and clinical studies have so far suggested that polyunsaturated fatty acids (PUFAs) could have health benefits and the advantage as therapeutic use in cancer treatment. However, the underlying mechanisms of PUFA-induced cellular effects remained to be cleared. Here, we examined the effects of omega-3 and to omega-6 PUFAs on cell death in ovarian cancer cell lines. omega-3 PUFA, docosahexaenoic acid (DHA) and omega-6 PUFA, gamma-linolenic acid (gamma-LNA) induced cell death in KF28 cells at the levels of physiological concentrations, but not HAC2 cells. Pharmacological and biochemical analyses demonstrated that cell death induced by DHA and gamma-LNA was correlated with activation of JNK and p38 MAP kinases, and further an upstream MAP kinase kinase, apoptosis signal -regulating kinase 1, which is stimulated by reactive oxygen species (ROS). Furthermore, an antioxidant vitamin E attenuated PUFA-induced cell death and MAP kinase activation. These findings indicate that PUFA-induced cell death involves ROS-dependent MAP kinase activation and is a cell type -specific action. A further study of the underlying mechanisms for ROS-dependent cell death induced by PUFAs will lead to the discovery of a new target for cancer therapy or diagnosis. (C) 2017 Elsevier Inc. All rights reserved.
  • Enhanced cellular functions through induction of LPA(2) by cisplatin in fibrosarcoma HT1080 cells, Kaede Takahashi, Kaori Fukushima, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, MOLECULAR AND CELLULAR BIOCHEMISTRY, MOLECULAR AND CELLULAR BIOCHEMISTRY, 431(1-2), 29 - 35, Jul. 2017 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a simple biophysical lipid which interacts with at least six subtypes of G protein-coupled LPA receptors (LPA(1)-LPA(6)). In cancer cells, LPA signaling via LPA receptors is involved in the regulation of malignant properties, such as cell growth, motility, and invasion. The aim of this study was to assess whether LPA receptors regulate cellular functions of fibrosarcoma cells treated with anticancer drug. HT1080 cells were maintained by the stepwise treatment of cisplatin (CDDP) at a range of 0.01 to 1.0 A mu M for approximately 6 months. The cell motile and invasive activities of long-term CDDP-treated (HT-CDDP) cells were significantly stimulated by LPA treatment, while HT-CDDP cells in the static state showed the low cell motile and invasive activities in comparison with HT1080 cells. Since the expression level of LPAR2 gene was markedly elevated in HT-CDDP cells, LPA(2) knockdown cells were generated from HT-CDDP cells. The cell motile and invasive activities of HT-CDDP cells were reduced by LPA(2) knockdown. In colony assay, large-sized colonies formed by long-term CDDP treatment were suppressed by LPA(2) knockdown. In addition, LPA(2) knockdown cells reduced LPA production by autotaxin (ATX), correlating with ATX expression level. These results suggest that LPA signaling via LPA(2) may play an important role in the regulation of cellular functions in HT1080 cells treated with CDDP.
  • Functional characterization of lysophosphatidic acid receptor 1 mutants identified in rat cancer tissues, Shoichi Ishii, Toshifumi Tsujiuchi, Nobuyuki Fukushima, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 486(3), 767 - 773, May 2017 , Refereed
    Summary:Lysophosphatidic acid (LPA), an extracellular lipid mediator, exerts various cellular effects through activation of LPA receptors, LPA(1)-LPA(6), in many types of cells including cancer cells. We recently found several missense mutations of Lpar1 in rat cancer tissues. One of these mutations is located at the extracellular tip of the seventh transmembrane domain of LPA(1), and another three mutations are found within the NPXXY motif in the seventh transmembrane domain. These mutants are designated F295S LPA(1) and P308S, 1310T, and Y311H LPA(1), respectively. Here, we examined the functions of these LPA(1) mutants. Compared with wild-type (WT) LPA(1), F295S, P308S, and 1310T LPA(1) showed decreased maximal responses in inhibition of cAMP formation, Ca2+ mobilization, and cytoskeletal changes. Y311H LPA(1) failed to show LPA-induced cellular responses. However, these LPA(1) mutants were internalized in response to LPA exposure. Finally, while WT and F295S LPA(1) showed a similar, broad distribution throughout the cell, P308S, 1310T, and Y311H LPA(1) displayed a restricted cellular distribution and co-localized with the endoplasmic reticulum. These data suggest that the LPA(1) mutants perturb LPA signaling in cancer tissues. (C) 2017 Elsevier Inc. All rights reserved.
  • Different Induction of LPA Receptors by Chemical Liver Carcinogens Regulates Cellular Functions of Liver Epithelial WB-F344 Cells, Miku Hirane, Shuhei Ishii, Ayaka Tomimatsu, Kaori Fukushima, Kaede Takahashi, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, MOLECULAR CARCINOGENESIS, MOLECULAR CARCINOGENESIS, 55(11), 1573 - 1583, Nov. 2016 , Refereed
    Summary:Lysophosphatidic acid (LPA) signaling via LPA receptors (LPA1 to LPA6) mediates a variety of cellular functions, including cell motility. In the present study, we investigated the effects of LPA receptors on cell motile activity during multi-stage hepatocarcinogenesis in rat liver epithelial WB-F344 cells treated with chemical liver carcinogens. Cells were treated with a initiator (N-nitrosodiethylamine (DEN)) and three promoters (phenobarbital (PB), okadaic acid (OA) and clofibrate) every 24 h for 2 days. Cell motile activity was elevated by DEN, correlating with Lpar3 expression. PB, OA, and clofibrate elevated Lpar1 expression and inhibited cell motile activity. To evaluate the effects of long-term treatment on cell motility, cells were treated with DEN and/or PB for at least 6 months. Lpar3 expression and cell motile activity were significantly elevated by the long-term DEN treatment with or without further PB treatment. In contrast, long-term PB treatment with or without further DEN elevated Lpar1 expression and inhibited cell motility. When the synthesis of extracellular LPA was blocked by a potent ATX inhibitor S32826 before cell motility assay, the cell motility induced by DEN and PB was markedly suppressed. These results suggest that activation of the different LPA receptors may regulate the biological functions of cells treated with chemical carcinogens. (C) 2015 Wiley Periodicals, Inc.
  • Negative Effects of G-Protein-Coupled Free Fatty Acid Receptor GPR40 on Cell Migration and Invasion in Fibrosarcoma HT1080 Cells, Shuhei Ishii, Yuka Kitamura, Miku Hirane, Ayaka Tomimatsu, Kaori Fukushima, Kaede Takahashi, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, MOLECULAR CARCINOGENESIS, MOLECULAR CARCINOGENESIS, 55(11), 1553 - 1559, Nov. 2016 , Refereed
    Summary:G-protein-coupled receptor 40 (GPR40) and GPR120 mediate a variety of biological functions by the binding of long and medium chain free fatty acids. In the present study, we investigated a role of GPR40 in the pathogenesis of fibrosarcoma HT1080 cells. The GPR40 gene expression was detected in HT1080 cells, but not the GPR120 gene. The cell motile and invasive activities were markedly enhanced by GPR40 knockdown, compared with control cells. To evaluate whether GPR40 is involved in the cellular functions of HT1080 cells during anticancer drug treatment, HT1080 cells were maintained in condition medium containing cisplatin (CDDP) (0.01-1.0 mu M) for 6 mo. The expression levels of the GPR40 gene was elevated by the long-term CDDP treatment in HT1080 cells, while the GPR120 gene expression remained unchanged. The cell motile and invasive activities of HT1080 cells treated with CDDP were significantly lower than those of untreated cells. In gelatin zymography, the activities of matrix metalloproteinase-2 (MMP-2) and MMP-9 of HT1080 cells were enhanced by the long-term CDDP treatment. In addition, GW9508 which is an agonist of GPR40 and GPR120 suppressed the cell motile and invasive activities of HT1080 cells treated with CDDP as well as the MMP activation. These results suggest that GPR40 negatively regulates the tumor progression of fibrosarcoma cells. (C) 2015 Wiley Periodicals, Inc.
  • Diverse effects of G-protein-coupled free fatty acid receptors on the regulation of cellular functions in lung cancer cells, Tsubasa Kita, Yui Kadochi, Kaede Takahashi, Kaori Fukushima, Eri Yamasaki, Taiki Uemoto, Miku Hirane, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, EXPERIMENTAL CELL RESEARCH, EXPERIMENTAL CELL RESEARCH, 342(2), 193 - 199, Mar. 2016 , Refereed
    Summary:Free fatty acids (FFAs) are dietary nutrients which mediate a variety of biological effects through binding to G-protein-coupled FFA receptors (FFARs). G-protein-coupled receptor 120 (GPR120) and GPR40 are identified as FFARs for long- and medium-chain fatty acids. Here we investigated whether GPR120 and GPR40 are involved in the acquisition of malignant properties in lung cancer cells. Three lung cancer RLCNR, LL/2 and A549 cells used in this study expressed GPR120 and GPR40 genes. The cell motile activities of all cells were significantly suppressed by a GPR40 antagonist GW1100. In addition, GPR40 knockdown inhibited the cell motile activity of A549 cells. In gelatin zymography, matrix metalloproteinase-2 (MMP-2) activity in GPR40 knockdown was significantly lower than that in control cells. Next, to evaluate effects of GPR120 and GPR40 on cellular functions induced by anti-cancer drug, the long-term cisplatin (CDDP) treated (A549-CDDP) cells were generated. The expression levels of GPR120 and GPR40 were significantly decreased in A549-CDDP cells. While A549-CDDP cells showed the high cell motile activity, GW1100 suppressed the cell motile activity of A549-CDDP cells. These results demonstrate that GPR120 negatively and GPR40 positively regulate cellular functions during tumor progression in lung cancer cells. (C) 2016 Elsevier Inc. All rights reserved.
  • LPA signaling through LPA receptors regulates cellular functions of endothelial cells treated with anticancer drugs, Shiori Mori, Mutsumi Araki, Shuhei Ishii, Miku Hirane, Kaori Fukushima, Ayaka Tomimatsu, Kaede Takahashi, Nobuyuki Fukushima, Toshifumi Tsujiuchi, MOLECULAR AND CELLULAR BIOCHEMISTRY, MOLECULAR AND CELLULAR BIOCHEMISTRY, 408(1-2), 147 - 154, Oct. 2015 , Refereed
    Summary:Lysophosphatidic acid (LPA) signaling via LPA receptors provides a variety of cellular functions, including angiogenesis. In this study, to assess an involvement of LPA receptors in cell motile activities of endothelial cells during chemotherapy, F-2 cells were treated with cisplatin (CDDP) and doxorubicin (DOX) at a concentration of 0.01 mu M every 24 h for at least 1 month. The treatment of CDDP and DOX inhibited the expression levels of the LPA receptor-1 (Lpar1), Lpar2, and Lpar3 genes in F-2 cells. The cell motile activities of CDDP and DOX treated cells were relatively lower than those of untreated cells. Next, we investigated whether cancer cells could stimulate the cell motile activities of F-2 cells treated with CDDP and DOX. For cell motility assay, CDDP- and DOX-treated cells were co-cultured with pancreatic cancer PANC-1 cells. The cell motile activities of CDDP- and DOX-treated cells were significantly enhanced by the existence of PANC-1 cells, correlating with the LPA receptor expressions. In addition, the elevated cell motile activities were suppressed by the pretreatment of an autotaxin inhibitor S32826. These results suggest that LPA signaling via LPA receptors may regulate the cell motile activities of F-2 cells treated with anticancer drugs.
  • Different roles of GPR120 and GPR40 in the acquisition of malignant properties in pancreatic cancer cells, Kaori Fukushima, Eri Yamasaki, Shuhei Ishii, Ayaka Tomimatsu, Kaede Takahashi, Miku Hirane, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 465(3), 512 - 515, Sep. 2015 , Refereed
    Summary:Free fatty acids (FFAs) act as extracellular signaling molecules through binding to G-protein-coupled FFA receptors (FFARs). GPR120 and GPR40 are identified as FFARs for medium- and long-chain fatty acids. In the present study, we investigated roles of GPR120 and GPR40 in cellular functions of pancreatic cancer PANC-1 cells, using GPR120 and GPR40 knockdown cells (PANC-sh120 and PANC-sh40 cells respectively). In cell motility assay, PANC-sh120 cells showed the low cell motility, compared with control cells. In contrast, the cell motility of PANC-sh40 cells was significantly higher than that of control cells. Activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. While PANC-sh120 cells indicated the reduced MMP-2 activity, MMP-2 activity in PANC-sh40 cells was significantly higher than that in control cells. On the other hand, no activation of MMP-9 was detected in all cells. In colony assay, the large sized colonies were markedly formed in PANC-sh40 cells. No colony formation was observed in PANC-sh120 cells as well as control cells. These results suggest that distinct effects of GPR120 and GPR40 are involved in the acquisition of malignant property in pancreatic cancer cells. (C) 2015 Elsevier Inc. All rights reserved.
  • Comparative analyses of lysophosphatidic acid receptor-mediated signaling, Nobuyuki Fukushima, Shoichi Ishii, Toshifumi Tsujiuchi, Nao Kagawa, Kazutaka Katoh, CELLULAR AND MOLECULAR LIFE SCIENCES, CELLULAR AND MOLECULAR LIFE SCIENCES, 72(12), 2377 - 2394, Jun. 2015 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive lipid mediator that activates G protein-coupled LPA receptors to exert fundamental cellular functions. Six LPA receptor genes have been identified in vertebrates and are classified into two subfamilies, the endothelial differentiation genes (edg) and the non-edg family. Studies using genetically engineered mice, frogs, and zebrafish have demonstrated that LPA receptor-mediated signaling has biological, developmental, and pathophysiological functions. Computational analyses have also identified several amino acids (aa) critical for LPA recognition by human LPA receptors. This review focuses on the evolutionary aspects of LPA receptor-mediated signaling by comparing the aa sequences of vertebrate LPA receptors and LPA-producing enzymes; it also summarizes the LPA receptor-dependent effects commonly observed in mouse, frog, and fish.
  • Diverse effects of LPA(4), LPA(5) and LPA(6) on the activation of tumor progression in pancreatic cancer cells, Shuhei Ishii, Miku Hirane, Kaori Fukushima, Ayaka Tomimatsu, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 461(1), 59 - 64, May 2015 , Refereed
    Summary:Lysophosphatidic acid (LPA) is an extracellular biological lipid which interacts with G protein-coupled LPA receptors (LPA(1) to LPA(6)). LPA signaling via LPA receptors mediates several cellular responses. In the present study, to assess the roles of LPA(4), LPA(6) and LPA(6) in cellular functions of pancreatic cancer cells, we generated LEA receptor knockdown cells from PANC-1 cells (PANC-sh4, PANC-sh5 and PANC-sh6 cells, respectively). In cell motility assay, PANC-sh4 and PANC-sh5 cells enhanced the cell motile activities, compared with control cells. In contrast, the cell motile activity of PANC-sh6 cells was suppressed. The invasive activities of PANC-sh4 and PANC-sh5 cells were markedly stimulated, while PANC-sh6 cells showed the low invasive activity. In colony assay, PANC-sh4 and PANC-sh5 cells formed the large sized colonies, but not PANC-sh6 cells. When endothelial cells were incubated with supernatants from PANC-sh4 and PANC-sh5 cells, the cell motility and tube formation of endothelial cells were significantly induced, but not PANC-sh6 cells. These results suggest that the diverse roles of LPA(4), LPA(6) and LPA(6) are involved in the activation of tumor progression in pancreatic cancer cells. (C) 2015 Elsevier Inc. All rights reserved.
  • Role of GPR120 in cell motile activity induced by 12-O-tetradecanoylphorbol-13-acetate in liver epithelial WB-F344 cells, Shuhei Ishii, Miku Hirane, Yuka Kitamura, Shiori Mori, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, MOLECULAR AND CELLULAR BIOCHEMISTRY, MOLECULAR AND CELLULAR BIOCHEMISTRY, 400(1-2), 145 - 151, Feb. 2015 , Refereed
    Summary:G-protein-coupled receptor 120 (GPR120) is identified as a G-protein-coupled receptor for unsaturated long-chain free fatty acids that mediates insulin signaling and anti-inflammatory effects. Recently, it has been reported that GPR120 promotes the cell motile activity and angiogenesis in cancer cells. In this study, we assessed the role of GPR120 in the cell motile activity induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in rat liver epithelial WB-F344 cells. Cells were treated with TPA at a concentration of 5 nM for 72 h. The expression level of the Gpr120 gene was measured by quantitative real-time RT-PCR analysis. Cells treated with TPA showed the elevated Gpr120 expression, in comparison with untreated cells. In cell motility assays, the cell motile activity of cells treated with TPA was significantly higher than that of untreated cells. To confirm whether GPR120 is involved in the cell motile activity mediated by TPA, we generated GPR120 knockdown cells from WB-F344 cells. The cell motile activity induced by TPA was significantly suppressed by GPR120 knockdown. These results suggest that GPR120 plays an important role in the cell motile activity induced by TPA in WB-F344 cells.
  • Expression of the long-chain fatty acid receptor GPR120 in the gonadotropes of the mouse anterior pituitary gland, Ryutaro Moriyama, Chikaya Deura, Shingo Imoto, Kazuhiro Nose, Nobuyuki Fukushima, HISTOCHEMISTRY AND CELL BIOLOGY, HISTOCHEMISTRY AND CELL BIOLOGY, 143(1), 21 - 27, Jan. 2015 , Refereed
    Summary:G-protein-coupled receptor 120 (GPR120) has been known to be a receptor of long-chain fatty acids. Here, we investigated GPR120 expression in the mouse pituitary gland via real-time PCR, in situ hybridization, and immunohistochemistry. GPR120 mRNA was abundantly expressed in the pituitary gland of ad-lib fed animals. In situ hybridization and immunohistochemistry revealed GPR120 expression in the gonadotropes of the anterior pituitary gland, but not in thyrotropes, somatotropes, lactotropes, corticotropes, melanotropes, and the posterior pituitary gland. Furthermore, 24 h of fasting induced an increase in GPR120 mRNA expression in the pituitary gland. These results demonstrate that GPR120 in mouse pituitary gonadotropes is upregulated by fasting and that it may play a role in controlling gonadotropin secretion.
  • Opposite effects of GPR120 and GPR40 on cell motile activity induced by ethionine in liver epithelial cells, Shuhei Ishii, Miku Hirane, Sayumi Kato, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 456(1), 135 - 138, Jan. 2015 , Refereed
    Summary:Free fatty acids (FFAs) are dietary nutrients which act as ligands for FFAs receptors. G-protein-coupled receptor 120 (GPR120) and GPR40 are activated by long and medium chain FFAs. In the present study, we investigated the role of the GPR120 and GPR40 in cell motile activity stimulated by ethionine in rat liver epithelial WB-F344 cells. Cells were treated with ethionine at a concentration of 10 mu M every 24 h for 2 days. The expression levels of the Gpr120 and Gpr40 genes in WB-F344 cells treated ethionine were significantly higher than those in untreated cells. In cell motility assay, the cell motile activity of WB-F344 cells was markedly elevated by ethionine, compared with untreated cells. To evaluate the effects of GPR120 on the cell motile activity by ethionine, we established GPR120 knockdown cells from WB-F344 cells. The cell motile activity stimulated by ethionine was significantly suppressed by GPR120 knockdown. In addition, a potent GPR40 antagonist GW1100 enhanced the cell motile activity by ethionine. These results suggest that opposite effects of GPR120 and GPR40 may be involved in the cell motile activity stimulated by ethionine in WB-F344 cells. (C) 2014 Elsevier Inc. All rights reserved.
  • Functional lysophosphatidic acid receptors expressed in Oryzias latipes, Yuji Morimoto, Shoichi Ishii, Jun-ichi Ishibashi, Kazutaka Katoh, Toshifumi Tsujiuchi, Nao Kagawa, Nobuyuki Fukushima, GENE, GENE, 551(2), 189 - 200, Nov. 2014 , Refereed
    Summary:Lysophosphatidic acid (LPA) signaling is known to play biological and pathophysiological roles in many types of animals. Medaka (Oryzias latipes) is an experimental fish that can be easily maintained, propagated, and analyzed, and whose genome has been completely sequenced. However, there is limited information available regarding medaka LPA receptors. Here, using information from the medaka genome database, we examine the genomic structures, expression, and functions of six LPA receptor genes, Lpar1-Lpar6. Our analyses reveal that the genomic structures of Lpar1 and Lpar4 are different from those deduced from the database. Functional analyses using a heterologous expression system demonstrate that all medaka LPA receptors except for LPA(5b) respond to LPA treatment with cytoskeletal changes. These findings provide useful information on the structure and function of medaka LPA receptor genes, and identify medaka as a useful experimental model for exploration of the biological significance of LPA signaling. (C) 2014 Elsevier B.V. All rights reserved.
  • Lysophosphatidic acid receptor-5 negatively regulates cell motile and invasive activities of human sarcoma cell lines, Yan Dong, Miku Hirane, Mutsumi Araki, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, MOLECULAR AND CELLULAR BIOCHEMISTRY, MOLECULAR AND CELLULAR BIOCHEMISTRY, 393(1-2), 17 - 22, Aug. 2014 , Refereed
    Summary:LPA signaling via LPA receptors [LPA receptor-1 (LPA(1))-LPA(6)] mediates the several cellular responses in cancer cells, including cell motility and invasion. In the present study, to investigate a role of LPA(5) in the cell motile and invasive activities of sarcoma cells, LPAR5 knockdown (HOSL5 and HT1080L5) cells were generated from human osteosarcoma HOS and fibrosarcoma HT1080 cells, respectively. In cell motility assays with cell culture inserts, HOSL5 and HT1080L5 cells indicated the high cell motile activities, compared with control cells. The cell invasive activities of HOSL5 and HT1080L5 cells were significantly higher than those of control cells. Moreover, the activities of matrix metalloproteinase (MMP)-2 and MMP-9 were measured by gelatin zymography. MMP-2 was significantly activated in HOSL5 cells, but not MMP-9. The elevated activities of MMP-2 and MMP-9 were found in HT1080L5 cells, in comparison with control cells. These results suggest that LPA signaling via LPA(5) negatively regulates the cell motile and invasive activities of human sarcoma cells.
  • Long-term exposure of 3T3 fibroblast cells to endocrine disruptors alters sensitivity to oxidative injury, Yuka Nishimura, Yasuyoshi Nakai, Aiko Tanaka, Tetsuji Nagao, Nobuyuki Fukushima, CELL BIOLOGY INTERNATIONAL, CELL BIOLOGY INTERNATIONAL, 38(7), 868 - 874, Jul. 2014 , Refereed
    Summary:When Swiss 3T3 fibroblasts were exposed to bisphenol A (BPA) or nonylphenol (NP) within a range of 0.1-100 nM for 30-45 days, increased resistance to oxidative injury was found. Western blot analysis indicated concomitant increased expression of bcl-2 protein and reduced histone methylation levels in cells after BPA or NP exposure. Using a heterologous expression system, both chemicals could stimulate G protein-coupled receptor 30 (GPR30), a transmembrane estrogen receptor predominantly expressed in 3T3 cells, at lower concentrations, which gave increased survival. Taken together, these results suggest that BPA or NP exposure might cause alterations in cellular activity against oxidative stress, possibly through GPR30.
  • Diverse effects of LPA receptors on cell motile activities of cancer cells, Toshifumi Tsujiuchi, Miku Hirane, Yan Dong, Nobuyuki Fukushima, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, 34(3), 149 - 153, Jun. 2014 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive lipid that interacts with G protein-coupled transmembrane LPA receptors (LPA(1) to LPA(6)). LPA mediates a variety of cellular responses in normal cells, including cell growth, motility, differentiation, morphogenesis, and prevention from apoptosis. Furthermore, LPA signaling via LPA receptors is involved in the pathogenesis of several diseases, including cancer. Cell motility is one of the important properties during the progression of cancer cells. In recent studies, it has been demonstrated that LPA receptors have the diverse effects in the cell motile activities of cancer cells, depending on the cell types involved. In this review, we provide the current knowledge for the biological roles of LPA receptors in the cell motile activities of cancer cells.
  • Effects of bisphenol A and 4-nonylphenol on cellular responses through the different induction of LPA receptors in liver epithelial WB-F344 cells, Yan Dong, Mutsumi Araki, Miku Hirane, Eriko Tanabe, Nobuyuki Fukushima, Toshifumi Tsujiuchi, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, 34(3), 201 - 204, Jun. 2014 , Refereed
    Summary:Lysophosphatidic acid (LPA) signaling via G protein-coupled transmembrane LPA receptors (LPA(1) to LPA(6)) mediates a variety of cellular functions, including cell proliferation, migration, morphogenesis, and differentiation. Recently, we demonstrated that the different induction of LPA receptors by estrogens regulates cell motile activity of rat liver epithelial WB-F344 cells. In the present study, to assess whether endocrine disruptors (EDs) are involved in cellular functions through LPA signaling, we measured cell motile activity and LPA receptor expressions in WB-F344 cells treated with bisphenol A (BPA) and 4-nonylphenol (4-NP). Using quantitative real time RT-PCR analysis, the Lpar1 expression was elevated in BPA-treated cells, whereas the Lpar3 expression was decreased. In contrast, 4-NP increased the Lpar3 expression, but not the Lpar1 and Lpar2. For cell motility assay with a Cell Culture Insert, cell motile activity of BPA-treated cells was significantly lower than that of untreated cells. In contrast, 4-NP markedly enhanced cell motile activity. The effects of BPA and 4-NP on cell motility were inhibited by the Lpar1 or Lpar3 knockdown. These results suggest that BPA and 4-NP may regulate cell motile activity through the different induction of LPA receptors in WB-F344 cells.
  • Inhibitory effects of lysophosphatidic acid receptor-5 on cellular functions of sarcoma cells, Mutsumi Araki, Misaho Kitayoshi, Yan Dong, Miku Hirane, Shuhei Ozaki, Shiori Mori, Nobuyuki Fukushima, Kanya Honoki, Toshifumi Tsujiuchi, GROWTH FACTORS, GROWTH FACTORS, 32(3-4), 117 - 122, Jun. 2014 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive lipid that interacts with G protein-coupled LPA receptors (LPA receptor-1 (LPA(1)) to LPA(6)). Here, we investigated the effects of LPA signaling via LPA(5) on cellular functions of sarcoma cells by generating Lpar5 overexpressing and Lpar5 knockdown cells from rat osteosarcoma and malignant fibrous histiocytoma cells, respectively. The cell motility activity of Lpar5 overexpressing cells was significantly lower, while Lpar5 knockdown cells showed high cell motility, compared with respective controls. Gelatin zymography showed that LPA(5) suppressed the activation of matrix metalloproteinase-2. LPA(5) also inhibited the cell motility activity of endothelial cells, correlating with the expression levels of vascular endothelial growth factor genes. These results suggest that LPA signaling via LPA(5) negatively regulates the cellular functions of rat sarcoma cells.
  • Long-term pre-exposure of pheochromocytoma PC12 cells to endocrine-disrupting chemicals influences neuronal differentiation, Yuka Nishimura, Tetsuji Nagao, Nobuyuki Fukushima, NEUROSCIENCE LETTERS, NEUROSCIENCE LETTERS, 570, 1 - 4, Jun. 2014 , Refereed
    Summary:This study examined the effects of exposure to low concentrations (0.1-100 nM) of bisphenol A (BPA) or nonylphenol (NP) on neuronal differentiation in pheochromocytoma PC12 cells. Pre-exposure to BPA for a week or a month, but not for a day, decreased neuronal differentiation in PC12 cells. Likewise, one week's pre-exposure to NP also inhibited neuronal differentiation in these cells. The inhibitory effects were still observed when PC12 cells were treated with BPA or NP for a week, followed by a week's withdrawal. These findings suggest that long-term exposure of PC12 cells to low concentrations of BPA or NP leads to changes in the cellular machinery responsible for neuronal differentiation, and these changes might be retained within PC12 cells. (C) 2014 Elsevier Ireland Ltd. All rights reserved.
  • Lysophosphatidic acid receptor-5 negatively regulates cellular responses in mouse fibroblast 3T3 cells, Yan Dong, Miku Hirane, Mutsumi Araki, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 446(2), 585 - 589, Apr. 2014 , Refereed
    Summary:Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA(1)-LPA(6)) mediates a variety of biological functions, including cell migration. Recently, we have reported that LPA(1) inhibited the cell motile activities of mouse fibroblast 313 cells. In the present study, to evaluate a role of LPA(5) in cellular responses, Lpar5 knockdown (3T3-L5) cells were generated from 3T3 cells. In cell proliferation assays, LPA markedly stimulated the cell proliferation activities of 3T3-L5 cells, compared with control cells. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3-L5 cells were significantly higher than those of control cells. The activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. 3T3-L5 cells stimulated the activation of Mmp-2, correlating with the expression levels of Mmp-2 gene. Moreover, to assess the co-effects of LPA(1) and LPA(5) on cell motile activities, Lpar5 knockdown (3T3a1-L5) cells were also established from Lpar1 over-expressing (3T3a1) cells. 3T3a1-L5 cells increased the cell motile activities of 3T3a1 cells, while the cell motile activities of 3T3a1 cells were significantly lower than those of control cells. These results suggest that LPA(5) may act as a negative regulator of cellular responses in mouse fibroblast 313 cells, similar to the case for LPA(1). (C) 2014 Elsevier Inc. All rights reserved.
  • Lysophosphatidic acid receptors in cancer pathobiology, Toshifumi Tsujiuchi, Mutsumi Araki, Miku Hirane, Yan Dong, Nobuyuki Fukushima, HISTOLOGY AND HISTOPATHOLOGY, HISTOLOGY AND HISTOPATHOLOGY, 29(3), 313 - 321, Mar. 2014 , Refereed
    Summary:Lysophosphatidic acid (LPA) receptors (LPA(1) to LPA(6)) are G protein-coupled transmembrane and mediate a variety of biological responses through the binding of LPA, such as cell proliferation, migration, morphogenesis and differentiation. Previously, high secretion levels of LPA were found in blood and ascites from patients with aggressive ovarian cancer. So far, numerical studies have demonstrated that LPA signaling via LPA receptors contributes to the acquisition of malignant potency by several cancer cells. Moreover, genetic and epigenetic alterations of LPA receptor genes have been detected in cancer cells. Therefore, it is suggested that LPA signaling may be a target molecule for the establishment of chemoprevention agents in clinical cancer approaches. Here, we review the current knowledge for the biological roles of LPA signaling via LPA receptors in the pathogenesis of cancer cells.
  • Ethionine regulates cell motile activity through LPA receptor-3 in liver epithelial WB-F344 cells, Serina Inoue, Eriko Tanabe, Ayano Shibata, Miku Hirane, Mutsumi Araki, Yan Dong, Nobuyuki Fukushima, Toshifumi Tsujiuchi, MOLECULAR AND CELLULAR BIOCHEMISTRY, MOLECULAR AND CELLULAR BIOCHEMISTRY, 383(1-2), 173 - 177, Nov. 2013 , Refereed
    Summary:Lysophosphatidic acid (LPA) receptors (LPA(1) to LPA(6)) indicate a variety of cellular responses, such as cell proliferation, migration, differentiation, and morphogenesis. However, the role of each LPA receptor is not functionally equivalent. Ethionine, an ethyl analog of methionine, is well known to be one of the potent liver carcinogens in rats. In this study, to assess whether ethionine may regulate cell motile activity through LPA receptors, rat liver epithelial (WB-F344) cells were treated with ethionine for 48 h. In cell motility assay with a cell culture insert, the treatment of ethionine at 1.0 and 10 mu M enhanced significantly high cell motile activity, compared with untreated cells. The expression levels of LPA receptor genes in cells treated with ethionine were measured by quantitative real time RT-PCR analysis. The expression of the Lpar3 gene in ethionine-treated cells was significantly higher than that in untreated cells. Furthermore, to confirm an involvement of LPA(3) on cell motility increased by ethionine, the Lpar3 knockdown cells were also used. The cell motile activity by ethionine was completely suppressed in the Lpar3 knockdown cells. These results suggest that LPA signaling through LPA(3) may be involved in cell motile activity stimulated by ethionine in WB-F344 cells.
  • Inhibitory effects of LPA(1) on cell motile activities stimulated by hydrogen peroxide and 2,3-dimethoxy-1,4-naphthoquinone in fibroblast 3T3 cells, Miku Hirane, Mutsumi Araki, Yan Dong, Kanya Honoki, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 441(1), 47 - 52, Nov. 2013 , Refereed
    Summary:Reactive oxygen species (ROS) are known to mediate a variety of biological responses, including cell motility. Recently, we indicated that lysophosphatidic acid (LPA) receptor-3 (LPA(3)) increased cell motile activity stimulated by hydrogen peroxide. In the present study, we assessed the role of LPA(1) in the cell motile activity mediated by ROS in mouse fibroblast 3T3 cells. 3T3 cells were treated with hydrogen peroxide and 2,3-dimethoxy-1,4-naphthoquinone (DMNQ) at concentrations of 0.1 and 1 mu M for 48 h. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3 cells treated with hydrogen peroxide and DMNQ were significantly higher than those of untreated cells. 3T3 cells treated with hydrogen peroxide and DMNQ showed elevated expression levels of the Lpar3 gene, but not the Lpar1 and Lpar2 genes. To investigate the effects of LPA(1) on the cell motile activity induced by hydrogen peroxide and DMNQ, Lpar1-overexpressing (3T3-a1) cells were generated from 3T3 cells and treated with hydrogen peroxide and DMNQ. The cell motile activities stimulated by hydrogen peroxide and DMNQ were markedly suppressed in 3T3-a1 cells. These results suggest that LPA signaling via LPA(1) inhibits the cell motile activities stimulated by hydrogen peroxide and DMNQ in 3T3 cells. (C) 2013 Elsevier Inc. All rights reserved.
  • Lysophosphatidic acid receptor-3 increases tumorigenicity and aggressiveness of rat hepatoma RH7777 cells, Kyoko Okabe, Mai Hayashi, Kohei Kato, Mai Okumura, Rie Fukui, Kanya Honoki, Nobuyuki Fukushima, Toshifumi Tsujiuchi, MOLECULAR CARCINOGENESIS, MOLECULAR CARCINOGENESIS, 52(4), 247 - 254, Apr. 2013 , Refereed
    Summary:Lysophosphatidic acid (LPA), which interacts with G protein-coupled transmembrane LPA receptors exhibits several biological effects, such as cell proliferation, migration, and differentiation. Recently, it has been reported that alteration of LPA receptor genes occurs in several cancer cells. In this study, to assess the biological role of LPA receptor-3 (LPA3) in the pathogenesis of tumor cells, we generated the Lpar3-expressing cells (RHa3B12 and RHa3G8) from rat hepatoma RH7777 cells, and examined their abilities of cell migration and tumorigenicity, compared with the Lpar3-unexpressing cells. In cell motility and invasion assays, RHa3B12 and RHa3G8 cells showed significantly higher intrinsic activity without LPA treatment than control RH7777AB cells. LPA treatment further increased cell motility and invasion of these cells. The cell motility of RHa3B12 and RHa3G8 cells stimulated by LPA treatment was significantly suppressed by pretreatment with inhibitors of Gi or Gq proteins. In a soft agar assay, the large sized colonies were formed in RHa3B12 and RHa3G8 cells, but not in RH7777AB cells. The cell survival of RHa3G8 cells treated with cisplatin (CDDP) or doxorubicin (DOX) was higher than that of RH7777AB cells, correlating with the elevated expression levels of multidrug-resistance related genes, Mdr1a, Mdr1b, and Gstp1. These results suggest that LPA3 may be involved in progression and aggressiveness of rat hepatoma RH7777 cells. (c) 2011 Wiley Periodicals, Inc.
  • Involvement of oncogenic K-ras on cell migration stimulated by lysophosphatidic acid receptor-2 in pancreatic cancer cells, Kyohei Yoshikawa, Eriko Tanabe, Ayano Shibata, Serina Inoue, Misaho Kitayoshi, Souta Okimoto, Nobuyuki Fukushima, Toshifumi Tsujiuchi, EXPERIMENTAL CELL RESEARCH, EXPERIMENTAL CELL RESEARCH, 319(3), 105 - 112, Feb. 2013 , Refereed
    Summary:Lysophosphatidic acid (LPA) mediates a variety of cellular responses with atleast six G protein-coupled transmembrane receptors (LPA receptor-1 (LPA(1)-LPA(6))). The interaction between LPA receptors and other cellular molecules on the biological function is not fully understood. Recently, we have reported that LPA(1) suppressed and LPA(3) stimulated cell migration of pancreatic cancer cells. In the present study, to evaluate the function of LPA(2) on motile and invasive activities of pancreatic cancer cells, we generated Lpar2 knockdown (HPD-sh2) cells from hamster pancreatic cancer cells and measured their cell migration ability. In cell motility and invasive assays with an uncoated Cell Culture Insert, HPD-sh2 cells showed significantly lower intrinsic activity than control (HPD-GFP) cells. Since K-ras mutations were frequently detected in pancreatic cancer, we next investigated whether oncogenic K-ras is involved in cell migration induced by LPA2 using K-ras knockdown (HPD-K2) cells. The cell motile ability of HPD-K2 cells was significantly lower than that of control cells. To confirm LPA2 increases cell migration activity, cells were pretreated with dioctylglycerol pyrophosphate (DGPP) which is the antagonist of LPA(1)/LPA(3). The cell motile and invasive abilities of DGPP -treated HPD-GFP cells were markedly higher than those of untreated cells, but DGPP did not stimulate cell migration of HPD-K2 cells. These results suggest that cell migration activity of pancreatic cancer cells stimulated by LPA2 may be enhanced by oncogenic K-ras. (c) 2012 Elsevier Inc. All rights reserved.
  • Negative regulation of cell motile and invasive activities by lysophosphatidic acid receptor-3 in colon cancer HCT116 cells, Rie Fukui, Eriko Tanabe, Misaho Kitayoshi, Kyohei Yoshikawa, Nobuyuki Fukushima, Toshifumi Tsujiuchi, TUMOR BIOLOGY, TUMOR BIOLOGY, 33(6), 1899 - 1905, Dec. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) mediates a wide range of biological responses with G protein-coupled transmembrane receptors (LPA receptors). So far, at least six types of LPA receptors (LPA receptor-1 (LPA(1)) to LPA(6)) have been identified. Recently, it has been reported that LPA(3) indicates opposite effects on cellular functions of cancer cells. In the present study, to assess a biological role of LPA(3) on cell migration ability of colon cancer cells, we generated LPA receptor-3 (LPAR3) knockdown (HCT-sh3-3) cells from HCT116 and measured cell motile and invasion activities. In motility assay with a cell culture insert, HCT-sh3-3 cells showed significantly high cell motile activity, compared with control cells. For invasion assay, the filter was coated with Matrigel. The invasive activity of HCT-sh3-3 cells was significantly higher than that of control cells. Furthermore, we also examined the effects of LPAR3 knockdown on the interaction between colon cancer cells and endothelial F-2 cells. When F-2 cells were cultured with serum-free DMEM containing a supernatant from HCT-sh3-3 cells, the cell growth rate and migration activity of F-2 cells were significantly stimulated, associating with the elevated expressions of vascular endothelial growth factor (VEGF)-A and VEGF-C genes in HCT-sh3-3 cells. These results suggest that LPA(3) may act as a negative regulator on cell motile and invasive abilities of colon cancer HCT116 cells.
  • Loss of lysophosphatidic acid receptor-3 suppresses cell migration activity of human sarcoma cells, Eriko Tanabe, Misaho Kitayoshi, Kyohei Yoshikawa, Ayano Shibata, Kanya Honoki, Nobuyuki Fukushima, Toshifumi Tsujiuchi, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION, 32(6), 328 - 334, Dec. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) interacts with at least six G protein-coupled transmembrane LPA receptors (LPA(1)-LPA(6)). Recently, we have reported that LPA(3) indicated opposite effects on cell migration, depending on the cell types. In the present study, to assess an involvement of LPA(3) on cell migration of sarcoma cells, we generated LPA receptor-3 (LPAR3)-knockdown (HT1080-sh3 and HOS-sh3, respectively) cells from fibrosarcoma HT1080 and osteosarcoma HOS cells, and measured their cell migration abilities. In cell motility assay with a Cell Culture Insert, both LPAR3-knockdown cells showed significantly lower cell motile activities than control cells. Next, to investigate the effect of LPAR3-knockdown on invasion activity, which degraded the extracellular matrices, the Matrigel-coated filter was used. HT1080-sh3 cells showed significantly low invasive activity compared with control cells, while no invasive activity was found in HOS-sh3 cells. In gelatin zymography, no significant difference of matrix metalloproteinase (MMP)-2 and MMP-9 activities were detected in all cells. The results indicated that LPA(3) acts as a positive regulator of cell motility and invasion in sarcoma cells, suggesting that LPA signaling pathway via LPA(3) may be involved in the progression of sarcoma cells.
  • Regulation of cell motile activity through the different induction of LPA receptors by estrogens in liver epithelial WB-F344 cells, Eriko Tanabe, Ayano Shibata, Serina Inoue, Misaho Kitayoshi, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 428(1), 105 - 109, Nov. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) interacts with G protein-coupled transmembrane LPA receptors (LPA receptors; LPA(1)-LPA(6)). Recently, we demonstrated that each LPA receptor acts as a positive or negative regulator of cell migration ability. It is known that estrogens indicate a variety of biological functions, including cell motility. In the present study, to assess whether LPA signaling is involved in cell motile activity stimulated by estrogens, we measured cell motile activity and LPA receptor expressions of rat liver epithelial WB-F344 cells treated with 17 beta-estradiol (E-2), ethinyl estradiol (EE) and diethylstilbestrol (DES) at concentrations of 0.1 and 1.0 mu M for 48 h. The cell motility of E-2 and EE treated cells was significantly higher than that of untreated cells. By contrast, DES markedly inhibited cell motile activity. Using quantitative real time RT-PCR analysis, Lpar1 and Lpar3 expressions in E-2 treated cells were significantly higher than those in untreated cells. In EE treated cells, Lpar3 expression was markedly elevated, whereas Lpar1 expression was decreased. On the other hand, Lpar1 expression was significantly increased in DES treated cells. Interestingly, the effects of E-2, EE and DES on cell motility were suppressed by Lpar1 or Lpar3 knockdown. These results suggest that the different induction of LPA receptors by estrogens may regulate cell motile activity of WB-F344 cells. (C) 2012 Elsevier Inc. All rights reserved.
  • Opposite roles of LPA(1) and LPA(3) on cell motile and invasive activities of pancreatic cancer cells, Kohei Kato, Kyohei Yoshikawa, Eriko Tanabe, Misaho Kitayoshi, Rie Fukui, Nobuyuki Fukushima, Toshifumi Tsujiuchi, TUMOR BIOLOGY, TUMOR BIOLOGY, 33(5), 1739 - 1744, Oct. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) interacts with at least six G protein-coupled transmembrane LPA receptors. Recently, it has been demonstrated that each LPA receptor acts as a positive or negative regulator of cellular function. In the present study, to assess a biological role of LPA receptors on cell migration of pancreatic cancer cells, we generated LPA receptor-1 (LPA(1)) and LPA(3) knockdown cells from hamster pancreatic cancer cells by transfection with short hairpin RNA plasmids and measured their cell motile and invasive abilities. In cell motility and invasion assay, a Cell Culture Insert, coated with or without a Matrigel, was used. While the cell motility and invasion of Lpar1 knockdown cells were markedly enhanced than those of control cells, Lpar3 knockdown cells showed significantly lower cell motility and invasion. Moreover, to investigate an involvement of LPA(1) and LPA(3) in the development of pancreatic cancers, we also measured the expression levels of Lpar1 and Lpar3 genes in hamster pancreatic duct adenocarcinomas (PDAs) induced by a nitroso compound. The expressions of Lpar1 gene in PDAs were significantly lower than those in normal pancreatic tissues. By contrast, the elevated expressions of Lpar3 gene were detected in PDAs. We thus demonstrate that LPA(1) and LPA(3) play the different roles on cell migration ability of pancreatic cancer cells, suggesting the opposite effects via LPA(1) and LPA(3) may contribute to the pathogenesis of pancreatic cancers in hamsters.
  • Enhancement of endothelial cell migration by constitutively active LPA(1)-expressing tumor cells, Misaho Kitayoshi, Kohei Kato, Eriko Tanabe, Kyohei Yoshikawa, Rie Fukui, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 422(2), 339 - 343, Jun. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) receptors belong to G protein-coupled transmembrane receptors (LPA receptors; LPA(1) to LPA(6)). They indicate a variety of cellular response by the interaction with LPA, including cell proliferation, migration and differentiation. Recently, we have reported that constitutive active mutated LPA(1) induced the strong biological effects of rat neuroblastoma B103 cells. In the present study, we examined the effects of mutated LPA(1) on the interaction between B103 cells and endothelial F-2 cells. Each LPA receptor expressing B103 cells were maintained in serum-free DMEM and cell motility assay was performed with a Cell Culture Insert. When F-2 cells were cultured with conditioned medium from Lpar1 and Lpar3-expressing cells, the cell motility of F-2 cells was significantly higher than control cells. Interestingly, the motile activity of F-2 cells was strongly induced by mutated LPA(1) than other cells, correlating with the expression levels of vascular endothelial growth factor (Vegf)-A and Vegf-C. Pretreatment of LPA signaling inhibitors inhibited F-2 cell motility stimulated by mutated LPA(1). These results suggest that activation of LPA signaling via mutated LPA(1) may play an important role in the promotion of angiogenesis in rat neuroblastoma cells. (C) 2012 Elsevier Inc. All rights reserved.
  • Lysophosphatidic acid induces neurite branch formation through LPA(3), Daisuke Furuta, Masayuki Yamane, Toshifumi Tsujiuchi, Ryutaro Moriyama, Nobuyuki Fukushima, MOLECULAR AND CELLULAR NEUROSCIENCE, MOLECULAR AND CELLULAR NEUROSCIENCE, 50(1), 21 - 34, May 2012 , Refereed
    Summary:Although neurite branching is crucial for neuronal network formation after birth, its underlying mechanisms remain unclear. Here, we demonstrate that lysophosphatidic acid (LPA) stimulates neurite branching through a novel signaling pathway. Treatment of neuronal cell lines with LPA resulted in neurite branch formation when LPA(3) receptor was introduced. The effects of LPA were blocked by inhibition of G(q) signaling. Furthermore, expression of inhibitory mutants of the small GTPase Rnd2/Rho7 or an Rnd2 effector rapostlin abolished LPA(3)-mediated neurite branching. The LPA(3) agonist 2(S)-OMPT or LPA also induced axonal branch formation in hippocampal neurons, which was blocked by G(q) and Rnd2 pathway inhibition or LPA(3) knockdown. These findings suggest that the novel signaling pathway involving LPA(3), G(q), and Rnd2 may play an important role in neuronal network formation. (c) 2012 Elsevier Inc. All rights reserved.
  • Differential function of lysophosphatidic acid receptors in cell proliferation and migration of neuroblastoma cells, Mai Hayashi, Kyoko Okabe, Kohei Kato, Mai Okumura, Rie Fukui, Nobuyuki Fukushima, Toshifumi Tsujiuchi, CANCER LETTERS, CANCER LETTERS, 316(1), 91 - 96, Mar. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive lipid mediator that induces diverse cellular biological effects and interacts with G protein-coupled transmembrane LPA receptors. In the present study, to assess biological roles of LPA receptors in the pathogenesis of tumor cells, each LPA receptor (Lpar1, Lpar2 or Lpar3)-expressing rat neuroblastoma B103 cells (Ipa1-1, Ipa2-2 or Ipa3-3-2 cells, respectively) were used. In cell motility and invasion assay, Ipa2-2 and Ipa3-3-2 cells showed significant higher intrinsic activity without LPA treatment than LPA receptor-unexpressing AB2-1 bf cells. LPA treatment further increased cell motility of these cells, which was suppressed by the pretreatment with inhibitors of Gi, Gq protein, or ROCK. By contrast, Ipa1-1 cells markedly decreased intrinsic cell motility and invasion, compared with AB2-1 bf cells. Constitutively active mutant Lpar1-expressing cells (Ipa1 Delta-1) showed significant high motility, comparable with those of Ipa2-2 and Ipa3-3-2. In soft agar assay. Ipa3-3-2 and Ipa1 Delta-1 cells showed colony formation, but other cells failed. These results suggest that LPA receptors may play different roles in cell proliferation and migration of rat neuroblastoma cells. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
  • Constitutively active lysophosphatidic acid receptor-1 enhances the induction of matrix metalloproteinase-2, Kohei Kato, Rie Fukui, Kyoko Okabe, Eriko Tanabe, Misaho Kitayoshi, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 417(2), 790 - 793, Jan. 2012 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a simple phospholipid which interacts with at least six G protein-coupled transmembrane LPA receptors (LPA(1)-LPA(6)). In rat neuroblastoma B103 cells, we have recently reported that each LPA receptor indicates the different cellular functions, including cell motility, invasion and tumorigenicity. Especially, mutated and constitutively active LPA(1) enhanced these cellular effects in B103 cells. In the present study, to better understand a role of mutated LPA(1) underlying progression of cancer cells, we measured the expression and activity levels of matrix metalloproteinases (MMPs) in constitutively active mutant Lpar1-expressing B103 cells (lpa1 Delta-1), compared with each wild-type LPA receptor-expressing cells. LPA receptor-unexpressing cells were also used as control. In quantitative real time RT-PCR analysis, the expressions of Mmp-9 were detected at the same levels in all cells. By contrast, Mmp-2 expressions of lpa1 Delta-1 were significantly higher than those of other cells. In gelatin zymography, proMmp-9 was observed at the same levels in all cells. Interestingly, markedly high levels of proMmp-2 and Mmp-2 were detected in lpa1 Delta-1 cells, whereas no activation was in other cells. The increased expression and activity of Mmp-2 in lpa1 Delta-1 cells were suppressed by the pretreatment with a Gq protein inhibitor. These results suggest that mutated LPA(1) may involve in the enhancement of Mmp-2 expression and activation in rat neuroblastoma cells. (C) 2011 Elsevier Inc. All rights reserved.
  • Involvement of ERK in NMDA receptor-independent cortical neurotoxicity of hydrogen sulfide, Yuko Kurokawa, Fumiko Sekiguchi, Satoko Kubo, Yoshiko Yamasaki, Sachi Matsuda, Yukari Okamoto, Teruki Sekimoto, Anna Fukatsu, Hiroyuki Nishikawa, Toshiaki Kume, Nobuyuki Fukushima, Akinori Akaike, Atsufumi Kawabata, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 414(4), 727 - 732, Nov. 2011 , Refereed
    Summary:Hydrogen sulfide (H(2)S), a gasotransmitter, exerts both neurotoxicity and neuroprotection, and targets multiple molecules including NMDA receptors, T-type calcium channels and NO synthase (NOS) that might affect neuronal viability. Here, we determined and characterized effects of NaHS, an H(2)S donor, on cell viability in the primary cultures of mouse fetal cortical neurons. NaHS caused neuronal death, as assessed by LDH release and trypan blue staining, but did not significantly reduce the glutamate toxicity. The neurotoxicity of NaHS was resistant to inhibitors of NMDA receptors, T-type calcium channels and NOS, and was blocked by inhibitors of MEK, but not JNK, p38 MAP kinase, PKC and Src. NaHS caused prompt phosphorylation of ERK and upregulation of Bad, followed by translocation of Bax to mitochondria and release of mitochondrial cytochrome c(1) leading to the nuclear condensation/fragmentation. These effects of NaHS were suppressed by the MEK inhibitor. Our data suggest that the NMDA receptor-independent neurotoxicity of H(2)S involves activation of the MEK/ERK pathway and some apoptotic mechanisms. (C) 2011 Elsevier Inc. All rights reserved.
  • Distinct DNA methylation patterns of lysophosphatidic acid receptor genes during rat hepatocarcinogenesis induced by a choline-deficient L-amino acid-defined diet, Kyoko Okabe, Mai Hayashi, Ikuma Yoshida, Kazuki Nishimura, Nobuyuki Fukushima, Toshifumi Tsujiuchi, ARCHIVES OF TOXICOLOGY, ARCHIVES OF TOXICOLOGY, 85(10), 1303 - 1310, Oct. 2011 , Refereed
    Summary:Altered expressions of lysophosphatidic acid (LPA) receptor genes have been reported in tumor cells of human and rats. Recently, we detected the frequent mutations of LPA receptor-1 (LPA1) gene in rat hepatocellular carcinomas (HCCs) induced by a choline-deficient L-amino acid-defined (CDAA) diet. In this study, the DNA methylation patterns of LPA receptor genes and their expression levels during rat hepatocarcinogenesis induced by the CDAA diet were investigated. Six-week-old F344 male rats were continuously fed with the CDAA diet, and animals were then killed at 7 days and 2, 12, 20, and 75 weeks, respectively. Genomic DNAs were extracted from livers and HCCs for the assessment of methylation status by bisulfite sequencing, comparing to normal livers. The livers of rats fed the CDAA diet were unmethylated in LPA1 and LPA2 genes as well as normal livers. In LPA3 gene, although normal livers were unmethylated, the livers at 7 days and 2 and 12 weeks weakly or moderately methylated and those at 20 weeks markedly methylated. Moreover, 4 HCCs were completely methylated in LPA3 gene. Expression levels of LPA receptor genes in the livers of rats fed the CDAA diet and HCCs were correlating with DNA methylation status. These results indicate that DNA methylation status of the LPA3 gene was disturbed in the livers of rats fed the CDAA diet and established HCCs, suggesting that alterations of the LPA receptor genes might be involved during rat hepatocarcinogenesis induced by the CDAA diet.
  • Induction of lysophosphatidic acid receptor-3 by 12-O-tetradecanoylphorbol-13-acetate stimulates cell migration of rat liver cells, Kyoko Okabe, Kohei Kato, Miki Teranishi, Mai Okumura, Rie Fukui, Toshio Mori, Nobuyuki Fukushima, Toshifumi Tsujiuchi, CANCER LETTERS, CANCER LETTERS, 309(2), 236 - 242, Oct. 2011 , Refereed
    Summary:12-O-tetradecanoylphorbol-13-acetate (TPA) which is one of tumor promoting agents stimulates cell migration ability of several tumor cells. In the present study, we investigated whether lysophosphatidic acid (LPA) receptors are involved in cell migration of rat liver cells stimulated by TPA. The rat liver epithelial WB-F344 and hepatoma RH7777 cells were treated by TPA for 48 h. The expression levels of LPA receptor genes in those cells were measured by real-time reverse transcription (RT)-polymerase chain reaction (PCR) analysis. The expressions of the LPA receptor-3 (Lpar3) gene were significantly elevated in WB-F344 and RH7777 cells treated by TPA, but not Lpar1 and Lpar2 genes. In cell migration assay, TPA treatment showed markedly high cell migration in both cells. The pretreatment with inhibitors of Gi protein suppressed those migration abilities. We next generated the Lpar3 knockdown cells from WB-F344 cells and investigated the effect on cell migration. Interestingly, the cell migration of the knockdown cells was not stimulated by TPA. These results suggest that TPA-stimulated cell migration of rat liver cells may be mainly dependent on the LPA(3)-mediated effect. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
  • Possible Involvement of Lysophosphatidic Acid Receptor-5 Gene in the Acquisition of Growth Advantage of Rat Tumor Cells, Kyoko Okabe, Mai Hayashi, Yasuna Yamawaki, Miki Teranishi, Kanya Honoki, Toshio Mori, Nobuyuki Fukushima, Toshifumi Tsujiuchi, MOLECULAR CARCINOGENESIS, MOLECULAR CARCINOGENESIS, 50(8), 635 - 642, Aug. 2011 , Refereed
    Summary:Aberrant expressions of lysophosphatidic acid (LPA) receptor genes have been reported in tumor cells. Here, we measured the expression levels of the Lpa5 gene and its DNA methylation status in rat tumor cells, and investigated cell growth effects of LPA in Lpa5 expressed cells. Real-time reverse transcription (RT)-polymerase chain reaction (PCR) analysis revealed that increased expressions of the Lpa5 gene were detected in rat liver-derived hepatoma RH7777 and lung-derived adenocarcinoma RLCNR cells. For the analysis of methylation status, bisulfite sequencing was performed with RH7777 and RLCNR cells and compared with other tumor cells and liver epithelial cells. The Lpa5 gene in Lpa5 unexpressed cells and liver epithelial cells were highly methylated in the 50 upstream region. In contrast, the Lpa5 gene in RH7777 and RLCNR cells was unmethylated, correlating with increased expressions of Lpa5. In the assays for cell growth effects of LPA, LPA enhanced cell proliferation and motility in RH7777 and RLCNR cells. LPA also stimulated cell invasion in RLCNR, but not in RH7777 cells. In rat liver and lung tumors induced by nitroso-compounds, 4 out of 6 hepatocellular carcinomas and 5 out of 6 lung adenocarcinomas indicated increased expressions of Lpa5 with unmethylated status. These results suggest that increased Lpa5 expressions due to aberrant DNA methylation may be involved in the acquisition of growth advantage of rat tumor cells. (C) 2011 Wiley-Liss, Inc.
  • Coordinated interactions between actin and microtubules through crosslinkers in neurite retraction induced by lysophosphatidic acid, Nobuyuki Fukushima, Daisuke Furuta, Toshifumi Tsujiuchi, NEUROCHEMISTRY INTERNATIONAL, NEUROCHEMISTRY INTERNATIONAL, 59(2), 109 - 113, Aug. 2011 , Refereed
    Summary:Neurite development requires rearrangement of cytoskeletal elements, which are mechanically and functionally integrated with each other. Although the process of how an extracellular signal induces rearrangement of a single element has been closely examined, the mechanisms by which the signal regulates cytoskeletal integration during cell shape changes are poorly understood. We previously reported that lysophosphatidic acid (LPA) induces actin polymerization-dependent microtubule (MT) rearrangement, leading to neurite retraction in cultured neurons. Here we examined whether the crosslinker proteins were involved in LPA-induced neurite retraction using immortalized mouse neuroblast TR cells. When the MT-binding domains of MACF (MT actin-crosslinking factor) were exogenously expressed in TR cells, MTs were found to be stabilized and become resistant to exposure to LPA. On the other hand, expression of MT-associated protein 2c showed no effect on LPA-induced neurite retraction. These findings suggest that MACF is involved in actin-dependent MT rearrangement during LPA-induced neurite retraction. (C) 2011 Elsevier BM. All rights reserved.
  • Loss of lysophosphatidic acid receptor-3 enhances cell migration in rat lung tumor cells, Mai Hayashi, Kyoko Okabe, Yasuna Yamawaki, Miki Teranishi, Kanya Honoki, Toshio Mori, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 405(3), 450 - 454, Feb. 2011 , Refereed
    Summary:Lysophosphatidic acid (LPA) indicates several biological effects, such as cell proliferation, differentiation and migration. LPA interacts with G protein-coupled transmembrane LPA receptors. In our previous report, we detected that loss of the LPA receptor-1 (Lpar1) expression is due to its aberrant DNA methylation in rat tumor cell lines. In this study, to assess an involvement of the other LPA receptor, Lpar3, in the pathogenesis of rat lung tumor cells, we measured the expression levels of the Lpar3 gene and its DNA methylation status by reverse transcription (RT)-polymerase chain reaction (PCR) and bisulfite sequencing analyses, respectively. RLCNR lung adenocarcinoma cells showed reduced expression of the Lpar3, compared with normal lung tissues. In the 5' upstream region of the Lpar3, normal lung tissues were unmethylated. By contrast, RLCNR cells were highly methylated, correlating with reduced expressions of the Lpar3. Based on these results, we generated the Lpar3-expressing RLCNR-a3 cells and measured the cell migration ability. Interestingly, the cell migration of RLCNR-a3 cells was significantly lower than that of RLCNR cells. This study suggests that loss of the Lpar3 due to aberrant DNA methylation may be involved in the progression of rat lung tumor cells. (C) 2011 Elsevier Inc. All rights reserved.
  • Differential expressions and DNA methylation patterns of lysophosphatidic acid receptor genes in human colon cancer cells, Megumu Tsujino, Minako Fujii, Kyoko Okabe, Toshio Mori, Nobuyuki Fukushima, Toshifumi Tsujiuchi, VIRCHOWS ARCHIV, VIRCHOWS ARCHIV, 457(6), 669 - 676, Dec. 2010 , Refereed
    Summary:Lysophosphatidic acid (LPA), which is a bioactive phospholipid, interacts with specific G protein-coupled transmembrane receptors. Recently, alterations of LPA receptor genes have been reported in some tumor cells. In this study, we examined the expression profiles and DNA methylation status of LPA receptor 1-5 (LPA1-5) genes in human colon cancer cells and also looked for the mutations. Reverse transcription-polymerase chain reaction (PCR) and bisulfite sequencing analyses were carried out. While LPA1, LPA2, and LPA4 genes were expressed in DLD1, SW480, HCT116, CaCo-2, SW48, and LoVo cells, the expressions of LPA3 and LPA5 genes were various. These expression levels were correlated with DNA methylation status in the 5' upstream regions of the LPA receptor genes. Mutation analysis was also performed using a PCR-single-strand conformation polymorphism method. Although no mutations in LPA1, LPA3 and LPA5 genes were found in all types of cells, LPA2 mutations in DLD1 and SW48 cells, and LPA4 mutation were found in DLD1 cells. On the basis of the present results, we demonstrate that these colon cancer cells will be available to understanding the molecular pathway through LPA receptors in the development of tumor cells, and that LPA receptors may be new molecular targets for therapeutic approaches and chemoprevention.
  • Lysophosphatidic acid influences initial neuronal polarity establishment, Masayuki Yamane, Daisuke Furuta, Nobuyuki Fukushima, NEUROSCIENCE LETTERS, NEUROSCIENCE LETTERS, 480(2), 154 - 157, Aug. 2010 , Refereed
    Summary:Neuronal polarity is specified by neurite determination into axons and dendrites. Its establishment requires both extrinsic signals, which regulate axon and dendrite development through repulsive or attractive actions, and intrinsic cellular mechanisms, which include rearrangement and selective transport of the cytoskeleton and localization of intracellular organelles. However, it remains unclear how extrinsic signals activate intrinsic cellular mechanisms to establish neuronal polarity. Here, we examine the effects of lysophosphatidic acid (LPA), a signaling lipid that induces cytoskeletal rearrangement in neuronal cells, on neuronal polarity establishment. In hippocampal neuronal cultures where a concentration gradient of LPA was formed, the bases of axons were located predominantly at the side distal to the LPA source. Furthermore, Golgi apparatus were also positioned distally as early as 1 h after exposure to the LPA source, suggesting that LPA signaling is involved in the initial determination of the area where an axon sprouts, and thereby the establishment of neuronal polarity. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
  • No mutations of lysophosphatidic acid receptor genes in lung adenocarcinomas induced by N-Nitrosobis(2-hydroxypropyl)amine in rats, Naoko Wakabayashi, Megumu Tsujino, Masaki Tajiri, Midori Taki, Ayumi Koshino, Hiroko Ikeda, Nobuyuki Fukushima, Toshifumi Tsujiuchi, Journal of Toxicologic Pathology, Journal of Toxicologic Pathology, 23(1), 63 - 66, Apr. 2010 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation and migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, frequent mutations of the LPA receptor-1 (LPA1) gene were detected in rat lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl)amine (BHP). In this study, to evaluate the involvement of other LPA receptor gene alterations during lung carcinogenesis, we investigated mutations of the LPA2, LPA3, LPA4 and LPA5 genes in lung adenocarcinomas induced by BHP in rats. Fifteen male Wistar rats, 6 weeks of age, were given 2000 ppm BHP in their drinking water for 12 weeks and then maintained without further treatment until sacrifice at 25 weeks, and 15 adenocarcinomas were obtained. Genomic DNAs were extracted from frozen tissues, and the LPA2, LPA3, LPA4 and LPA5 genes were examined for mutations, using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. No mutations of LPA2, LPA3, LPA4 and LPA5 were detected in the 15 adenocarcinomas. These results suggest that alterations due to LPA2, LPA3, LPA4 and LPA5 gene mutations might not be involved in the development of lung adenocarcinomas induced by BHP in rats.
  • Mutations of Lysophosphatidic Acid Receptor Genes in Human Osteosarcoma Cells, Kyoko Okabe, Mai Hayashi, Minako Fujii, Kanya Honoki, Toshio Mori, Nobuyuki Fukushima, Toshifumi Tsujiuchi, PATHOBIOLOGY, PATHOBIOLOGY, 77(5), 278 - 282, 2010 , Refereed
    Summary:Objective: Lysophosphatidic acid (LPA), which is a bioactive phospholipid, interacts with specific G protein-coupled transmembrane receptors. Recently, alterations in LPA receptor genes have been reported in some tumor cells. In this study, to assess an involvement of LPA receptor genes in the development of human cancer cells, we looked for the presence of mutations in LPA receptor 1-6 (LPA1-6) genes in MG63 osteosarcoma, HT1080 fibrosarcoma, A549 lung adenocarcinoma, MCF-7 breast carcinoma, and G-361 melanoma cells. Methods: Genomic DNAs were extracted from each cell and polymerase chain reaction-single-strand conformation polymorphism analysis was performed to identify the mutations. Results: MG63 showed mutations in LPA1 and LPA3 genes, while no mutations in the LPA receptor genes were found in HT1080, A549, MCF-7 and G-361 cells. Sequence analysis revealed a CGC to CGT (Arg to Arg) transition at codon 314 in LPA1, and a GCG to GTG (Ala to Val) transition at codon 247 in LPA3. Conclusion: These results indicated that the mutations in LPA1 and LPA3 genes occur in MG63 cells, suggesting that the alterations in LPA receptor genes may play some role in the pathogenesis in human osteosarcoma cells. Copyright (C) 2010 S. Karger AG, Basel
  • Different Expressions and DNA Methylation Patterns of Lysophosphatidic Acid Receptor Genes in Mouse Tumor Cells, Kyoko Okabe, Mai Hayashi, Naoko Wakabayashi, Yasuna Yamawaki, Miki Teranishi, Nobuyuki Fukushima, Toshifumi Tsujiuchi, PATHOBIOLOGY, PATHOBIOLOGY, 77(6), 309 - 314, 2010 , Refereed
    Summary:Objective: Lysophosphatidic acid (LPA) receptors act as several biological effectors through LPA, which is a bioactive phospholipid. Recently, aberrant expressions of LPA receptor genes due to DNA methylation have been detected in several tumor cells. In this study, we measured expression levels and DNA methylation status of LPA receptor genes in mouse tumor cells, LL/2 lung carcinoma, B16F0 melanoma, FM3A mammary carcinoma and L1210 leukemia cells, compared with normal tissues. Methods: Total RNAs were extracted and RT-PCR analysis was performed. For DNA methylation status, bisulfite sequencing analysis was carried out, comparing outcomes with other tumor cells and normal tissues. Results: The expressions of LPA1 gene were shown in LL/2, but not in B16F0, FM3A and L1210 cells. While the LPA2 gene was expressed in all 4 tumor cells, the LPA3 gene was unexpressed in them. The LPA1 and LPA3 unexpressed cells were highly methylated, although normal tissues were all unmethylated. The DNA methylation status was correlated with gene expression levels in cancer cells. Conclusion: The present results demonstrate that DNA methylation patterns of LPA receptor genes are dependent on cancer cell types, suggesting that LPA receptors may be new molecular targets for therapeutic approaches and chemoprevention. Copyright (C) 2011 S. Karger AG, Basel
  • Post-translational modifications of tubulin in the nervous system, Nobuyuki Fukushima, Daisuke Furuta, Yuji Hidaka, Ryutaro Moriyama, Toshifumi Tsujiuchi, JOURNAL OF NEUROCHEMISTRY, JOURNAL OF NEUROCHEMISTRY, 109(3), 683 - 693, May 2009 , Refereed
    Summary:Many studies have shown that microtubules (MTs) interact with MT-associated proteins and motor proteins. These interactions are essential for the formation and maintenance of the polarized morphology of neurons and have been proposed to be regulated in part by highly diverse, unusual post-translational modifications (PTMs) of tubulin, including acetylation, tyrosination, detyrosination, Delta 2 modification, polyglutamylation, polyglycylation, palmitoylation, and phosphorylation. However, the precise mechanisms of PTM generation and the properties of modified MTs have been poorly understood until recently. Recent PTM research has uncovered the enzymes mediating tubulin PTMs and provided new insights into the regulation of MT-based functions. The identification of tubulin deacetylase and discovery of its specific inhibitors have paved the way to understand the roles of acetylated MTs in kinesin-mediated axonal transport and neurodegenerative diseases such as Huntington's disease. Studies with tubulin tyrosine ligase (TTL)-null mice have shown that tyrosinated MTs are essential in normal brain development. The discovery of TTL-like genes encoding polyglutamylase has led to the finding that polyglutamylated MTs which accumulate during brain development are involved in synapse vesicle transport or neurite outgrowth through interactions with motor proteins or MT-associated proteins, respectively. Here we review current exciting topics that are expected to advance MT research in the nervous system.
  • Frequent mutations of lysophosphatidic acid receptor-1 gene in rat liver tumors, Yumi Obo, Takanori Yamada, Mami Furukawa, Mayuko Hotta, Kanya Honoki, Nobuyuki Fukushima, Toshifumi Tsujiuchi, MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS, MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS, 660(1-2), 47 - 50, Jan. 2009 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with Specific G protein-coupled transmembrane receptors, including LPA1 to LPA5. In the present study, to clarify an involvement of LPA I gene alterations in the development of hepatocellular carcinomas (HCCs) we investigated the LPA1 mutations in rat HCCs induced by exogenous and endogenous liver carcinogenesis models. We induced HCCs in rats with N-nitrosodiethylamine (DEN) and a choline-deficient L-amino acid-defined (CDAA) diet. RNAs were extracted from 15 HCCS induced by DEN and 12 HCCs induced by the CDAA diet. To identify LPA1 mutations, reverse transcription (RT) - polymerase chain reaction (PCR) - single strand conformation polymorphism (SSCP) analysis, followed by nucleotide sequencing, was performed. Missense mutations were detected in 7 out of 15 HCCs (46.7%,) induced by DEN. Five Out of 12 HCCs (41.7%,) induced by the CDAA diet also showed missense mutations. These results demonstrated that mutations in LPA1 gene occur in rat HCCs induced by DEN and the CDAA diet, suggesting that LPA1 mutations may be essentially involved ill rat liver carcinogenesis. (c) 2008 Elsevier B.V. All rights reserved.
  • Mutations of lysophosphatidic acid receptor-1 gene during progression of lung tumors in rats, Takanori Yamada, Yumi Obo, Mami Furukawa, Mayuko Hotta, Ayako Yamasaki, Kanya Honoki, Nobuyuki Fukushima, Toshifumi Tsujiuchi, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 378(3), 424 - 427, Jan. 2009 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. In this study, mutations of lysophosphatidic acid receptor-1 (LPA1) gene were investigated to clarify the possible molecular mechanisms underlying the development of lung tumors induced by N-nitrosobis(2-hydroxypropyl)amine (BHP) in rats. Male Wistar rats, 6 weeks of age. were given 2000 ppm BHP in their drinking water for 12 weeks and then maintained without further treatment until sacrifice at 25 weeks. Genomic DNAs were extracted from paraffin-embedded tissues and exons 2-4 were examined for mutations, using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. No LPA1 mutations were detected in 15 hyperplasias, but 2 out of 12 adenomas (16.7%) and 7 Out Of 17 adenocarcinomas (41.2%). These results suggest that mutations of LPA1 gene may be involved in the acquisition of growth advantage from adenomas to adenocarcinomas in lung carcinogenesis induced in rats by BHP. (C) 2008 Elsevier Inc. All rights reserved.
  • Infrequent Mutation of Lysophosphatidic Acid Receptor-1 Gene in Hamster Pancreatic Duct Adenocarcinomas and Established Cell Lines, Toshifumi Tsujiuchi, Mami Furukawa, Yumi Obo, Ayako Yamasaki, Mayuko Hotta, Chie Kusunoki, Naoko Suyama, Toshio Mori, Kanya Honoki, Nobuyuki Fukushima, JOURNAL OF TOXICOLOGIC PATHOLOGY, JOURNAL OF TOXICOLOGIC PATHOLOGY, 22(1), 89 - 92, 2009 , Refereed
    Summary:To evaluate the involvement of lysophosphatidic acid receptor-1 (LPA1) gene alteration in pancreatic carcinogenesis, we investigated mutations in the LPA1 gene in hamster pancreatic duct adenocarcinomas (PDAs) and established cell lines. Female Syrian golden hamsters received 30 mg/kg of N-nitrosobis(2-oxopropyl) amine (BOP) followed by repeated exposure to an augmentation pressure regimen consisting of a choline-deficient diet combined with DL-ethionine and then L-methionine and a further administration of 20 mg/kg BOP. A total of 10 PDAs obtained 10 weeks after beginning the experiment and three cell lines established from subcutaneously transplantable PDAs in syngeneic hamsters were examined for mutations using reverse transcription-polymerase chain reaction-single strand conformation polymorphism (RT-PCR-SSCP) analysis. A mutation was detected in only one PDA (1/10, 10%) in the form of a GGA to GTA (Gly to Val) transversion at codon 355, and no mutations were detected in the three cell lines. These results suggest that the LPA1 gene mutation may play roles in a limited fraction of BOP-induced pancreatic duct carcinogenesis in hamsters. (J Toxicol Pathol 2009; 22: 89-92)
  • A lysophosphatidic acid receptor lacking the PDZ-binding domain is constitutively active and stimulates cell proliferation, Shinya Shano, Kazuki Hatanaka, Shinsuke Ninose, Ryutaro Moriyama, Toshifumi Tsujiuchi, Nobuyuki Fukushima, BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH, BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH, 1783(5), 748 - 759, May 2008
    Summary:Lysophosphatidic acid (LPA) is an extracellular signaling lipid that regulates cell proliferation, survival, and motility of normal and cancer cells. These effects are produced through G protein-coupled LPA receptors, LPA(1) to LPA(5). We generated an LPA(1) mutant lacking the SerValVal sequence of the C-terminal PDZ-binding domain to examine the role of this domain in intracellular signaling and other cellular functions. B103 neuroblastoma cells expressing the mutant LPA(1) showed rapid cell proliferation and tended to form colonies under serum-free conditions. The enhanced cell proliferation of the mutant cells was inhibited by exogenous expression of the plasmids inhibiting G proteins including G(beta gamma), G(alpha i) and G(alpha q) or G(alpha 12/13), or treatment with pertussis toxin, phosphoinositide 3-kinase (PI3K) inhibitors or a Rho inhibitor. We confirmed that the PI3K-Akt and Rho pathways were intrinsically activated in mutant cells by detecting increases in phosphorylated Akt in western blot analyses or by directly measuring Rho activity. Interestingly, expression of the mutant LPA(1) in non-tumor mouse fibroblasts induced colony formation in a clonogenic soft agar assay, indicating that oncogenic pathways were activated. Taken together, these observations suggest that the mutant LPA(1) constitutively activates the G protein signaling leading to PI3K-Akt and Rho pathways, resulting in enhanced cell proliferation. (C) 2007 Elsevier B.V. All rights reserved.
  • Lysophosphatidic acid stimulates astrocyte proliferation through LPA(1), Shinya Shano, Ryutaro Moriyama, Jerold Chun, Nobuyuki Fukushima, NEUROCHEMISTRY INTERNATIONAL, NEUROCHEMISTRY INTERNATIONAL, 52(1-2), 216 - 220, Jan. 2008
    Summary:Lysophosphatidic acid (LPA) is an extracellular lipid mediator that regulates nervous system development and functions through multiple types of LPA receptors. Here we explore the role of LPA receptor subtypes in cortical astrocyte functions. Astrocytes cultured under serum-free conditions were found to express the genes of five LPA receptor subtypes, lpa(1) to lpa(5). When astrocytes were treated with dibutyryl cyclic adenosine monophosphate, a reagent inducing astrocyte differentiation or activation, lpa(1) expression levels remained unchanged, but those of other LPA receptor subtypes were relatively reduced. LPA stimulated DNA synthesis in both undifferentiated and differentiated astrocytes, but failed to do so in astrocytes prepared from mice lacking lpa(1) gene. LPA also inhibited [H-3]-glutamate uptake in both undifferentiated and differentiated astrocytes; and LPA-induced inhibition of glutamate uptake was still observed in lpa(1)-deficient astrocytes. Taken together, these observations demonstrate that LPA(1) mediates LPA-induced stimulation of cell proliferation but not inhibition of glutamate uptake in astrocytes. (C) 2007 Elsevier Ltd. All rights reserved.
  • Lysophosphatidic acid stimulates neuronal differentiation of cortical neuroblasts through the LPA(1)-G(i/o) pathway, Nobuyuki Fukushima, Shinya Shano, Ryutaro Moriyama, Jerold Chun, NEUROCHEMISTRY INTERNATIONAL, NEUROCHEMISTRY INTERNATIONAL, 50(2), 302 - 307, Jan. 2007
    Summary:Lysophosphatidic acid (LPA) is an extracellular lipid mediator that regulates cortical development. Here we examined how LPA influences the cell fate of cortical neuroblasts using a neurosphere culture system. We generated neurospheres in the presence of basic fibroblast growth factor (bFGF). Treatment with LPA throughout the culture period significantly reduced the number of cells in the neurospheres. When dissociated single cells derived from neurospheres were induced to differentiate by adherence on coverslips, the proportion of MAP2-positive neurons was higher in LPA-treated neurospheres than in those treated with bFGF alone, and the proportion of myelin basic protein-positive oligodendrocytes was lower. Consistent with this finding, LPA raised the ratio of beta-tubulin type III-positive young neurons and reduced the ratio of CD140a-positive oligodendrocyte precursors in neurospheres. These effects of LPA were inhibited by pretreatment of neurospheres with pertussis toxin or an LPA(1)-preferring antagonist, Ki16425. Moreover, LPA-induced enhancement of neuronal differentiation was not observed in neurospheres derived from lpa(1)-null mice. These results suggest that LPA promotes the commitment of neuroblasts to the neural lineage through the LPA(1)-G(i/o) pathway. (c) 2006 Elsevier Ltd. All rights reserved.
  • Actomyosin-dependent microtubule rearrangement in lysophosphatidic acid-induced neurite remodeling of young cortical neurons, Nobuyuki Fukushima, Yuka Morita, BRAIN RESEARCH, BRAIN RESEARCH, 1094, 65 - 75, Jun. 2006
    Summary:It has been shown that lysophosphatidic acid (LPA), a signaling phospholipid, induces neurite retraction and the formation of retraction fibers in young cortical neurons by actin rearrangement. This study examined the rearrangement of microtubules (MTs) during LPA-induced neurite remodeling by immunostaining with antibodies against several types of tubulin. The results showed that alpha-tubulin was present in growing neurites as well as in cell bodies with various localization profiles. Exposure of neurons to LPA resulted in neurite retraction, accompanied by the rearrangement of MTs in neurites and the accumulation of MTs in cell bodies, without significant changes in the total amount of MTs in the cytoskeletal fraction of cultured neurons. Similar findings were obtained when young neurons were stained for other types of tubulin, including beta-tubulin type III and posttranslationally acetylated and tyrosinated tubulin. LPA-induced MT rearrangement was accompanied by accumulation of myosin IIB and polymerized actin at the base of retraction fibers. These effects of LPA on MTs and myosin 1113 were blocked by pretreatment with inhibitors of the actomyosin and Rho pathways (cytochalasin D, blebbistatin, and Y27632), but not by an MT stabilizer (taxol), whereas taxol inhibited neurite retraction and MT depolymerization induced by nocodazole. Furthermore, neurofilaments also showed rearrangement in response to LPA, which was blocked by cytochalasin D and Y27632, but not taxol. Taken together, these results suggested that LPA did not induce MT depolymerization and that LPA-induced actomyosin activation produced MT and neurofilament rearrangement, leading to neurite remodeling. (c) 2006 Elsevier B.V. All rights reserved.
  • Characterization of lpa(2) (Edg4) and lpa(1)/lpa(2) (Edg2/Edg4) lysophosphatidic acid receptor knockout mice: Signaling deficits without obvious phenotypic abnormality attributable to lpa(2), JJA Contos, Ishii, I, N Fukushima, MA Kingsbury, XQ Ye, S Kawamura, JH Brown, J Chun, MOLECULAR AND CELLULAR BIOLOGY, MOLECULAR AND CELLULAR BIOLOGY, 22(19), 6921 - 6929, Oct. 2002 , Refereed
    Summary:Lysophosphatidic acid (LPA), a bioactive lipid produced by several cell types including postmitotic neurons and activated platelets, is thought to be involved in various biological processes, including brain development. Three cognate G protein-coupled receptors encoded by lpa(1)/lp(A1)/Edg-2/Gpcr26, lpa(2)/lp(A2)/Edg-4, and lpa(3)/lp(A3)/Edg-7 mediate the cellular effects of LPA. We have previously shown that deletion of lpa(1) in mice results in craniofacial dysmorphism, semilethality due to defective suckling behavior, and generation of a small fraction of pups with frontal hematoma. To further investigate the role of these receptors and LPA signaling in the organism, we deleted lpa(2) in mice. Homozygous knockout (lpa(2)((-/-))) mice were born at the expected frequency and displayed no obvious phenotypic abnormalities. Intercrosses allowed generation of lpa(1)((-/-)) lpa(2)((-/-)) double knockout mice, which displayed no additional phenotypic abnormalities relative to lpa(1)((-/-)) mice except for an increased incidence of perinatal frontal hematoma. Histological analyses of lpa(1)((-/-)) lpa(2)((-/-)) embryonic cerebral cortices did not reveal obvious differences in the proliferating cell population. However, many LPA-induced responses, including phospholipase C activation, Ca2+ mobilization, adenylyl cyclase activation, proliferation, JNK activation, Akt activation, and stress fiber formation, were absent or severely reduced in embryonic fibroblasts derived from lpa(1)((-/-)) lpa(2)((-/-)) mice. Except for adenylyl cyclase activation [which was nearly abolished in lpa(1)((-/-)) fibroblasts], these responses were only partially affected in lpa(1)((-/-)) and lpa(2)((-/-)) fibroblasts. Thus, although LPA(2) is not essential for normal mouse development, it does act redundantly with LPA(1) to mediate most LPA responses in fibroblasts.
  • Dual regulation of actin rearrangement through lysophosphatidic acid receptor in neuroblast cell lines: Actin depolymerization by Ca2+-alpha-actinin and polymerization by Rho, N Fukushima, Ishii, I, Y Habara, CB Allen, J Chun, MOLECULAR BIOLOGY OF THE CELL, MOLECULAR BIOLOGY OF THE CELL, 13(8), 2692 - 2705, Aug. 2002 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a potent lipid mediator with actions on many cell types. Morphological changes involving actin polymerization are mediated by at least two cognate G protein-coupled receptors, LPA(1)/EDG-2 or LPA(2)/EDG-4. Herein, we show that LPA can also induce actin depolymerization preceding actin polymerization within single TR mouse immortalized neuroblasts. Actin depolymerization resulted in immediate loss of membrane ruffling, whereas actin polymerization resulted in process retraction. Each pathway was found to be independent: depolymerization mediated by intracellular calcium mobilization, and a-actinin activity and polymerization mediated by the activation of the small Rho GTPase. alpha-Actinin-mediated depolymerization seems to be involved in growth cone collapse of primary neurons, indicating a physiological significance of LPA-induced actin depolymerization. Further evidence for dual regulation of actin rearrangement was found by heterologous retroviral transduction of either lpa(1) or lpa(2) in B103 cells that neither express LPA receptors nor respond to LPA, to confer both forms of LPA-induced actin rearrangements. These results suggest that diverging intracellular signals from a single type of LPA receptor could regulate actin depolymerization, as well as polymerization, within a single cell. This dual actin rearrangement may play a novel, important role in regulation of the neuronal morphology and motility during brain development.
  • Lysophosphatidic acid influences the morphology and motility of young, postmitotic cortical neurons, N Fukushima, JA Weiner, D Kaushal, JJA Contos, SK Rehen, MA Kingsbury, KY Kim, J Chun, MOLECULAR AND CELLULAR NEUROSCIENCE, MOLECULAR AND CELLULAR NEUROSCIENCE, 20(2), 271 - 282, Jun. 2002 , Refereed
    Summary:Lysophosphatidic acid (LPA) is a bioactive lysophospholipid that produces process retraction and cell rounding through its cognate receptors in neuroblastoma cell lines. Although the expression profile of LPA receptors in developing brains suggests a role for LPA in central nervous system (CNS) development, how LPA influences the morphology of postmitotic CNS neurons remains to be determined. Here we have investigated the effects of exogenous LPA on the morphology of young, postmitotic neurons in primary culture. When treated with LPA, these neurons responded by not only retracting processes but also producing retraction fiber "caps" characterized by fine actin filaments emanating from a dense core. Retraction fiber caps gradually vanished due to the outward spread of regrowing membranes along the fibers, suggesting a role for caps as scaffolds for regrowth of retracted processes. Furthermore, LPA also affects neuronal migration in vitro and in vivo. Taken together, these results implicate LPA as an extracellular lipid signal affecting process outgrowth and migration of early postmitotic neurons during development.

Books etc

  • Lysophosphatidic acid receptor. Encyclopedia of SIgnaling Molecules,, Fukushima, N, Kado T, Tsujiuchi, T, Springer,   2017
  • Neural effects of LPA signaling. In Lysophospholipid Receptors: Signaling and Biochemistry., FUKUSHIMA Nobuyuki, Sole author, Wiley,   2013
  • Cytoskeleton of the Nervous System, Advances in Neurobiology, Microtubules in the Nervous System., Fukushima, N, Sole author, Springer,   2011

Conference Activities & Talks

  • Molecular mechanism of LPA3-mediated axonal branching formation in cultured hippocampal neurons,   2010 12
  • Lysophosphatidic acid receptor 3 activation induces axonal branch formation in cultured hippocampal neurons,   2010 09
  • Palmitate regulates GnRH receptor mRNA expression level in the gonadotrope of the mouse anterior pituitary gland., 14th International Congress of Endocrinology,   2010 03 , 14th International Congress of Endocrinology
  • Lysophosphatidic acid receptor 3 is involved in neurite branching formation in hippocampal neurons,   2009 10
  • LPA induces neurite shape changes through LPA3, PLM2009,   2009 05 , PLM2009
  • Regulation of neurite morphology by LPA, PLM2009,   2009 05 , PLM2009
  • Palmitate regulates GnRH receptor mRNA expression level in the gonadotrope of the mouse pituitary gland.,   2009 05
  • Palmitate regulates GnRH receptor mRNA expression in the gonadotrope of the mouse anterior pituitary,   2008 07
  • Fasting induced increase in long-chain fatty acid receptor GPR120 expression in the gonadotrope of the mouse anterior pituitary., 37th Annual Meeting of Society for Neuroscience,   2007 11 , 37th Annual Meeting of Society for Neuroscience
  • Palmitate-induced increase in long-chain fatty acid receptor GPR120 mRNA level in LβT2 pituitary gonadotrope cells.,   2007 09
  • Fasting induced Long-chain fatty acid receptor GPR120 expression increase in the anterior pituitary of mouse.,   2006 07