Molecular Mechanisms for injury-dependent activation of c-Met, HGF receptor

c-Met、HGF 受体损伤依赖性激活的分子机制

• 批准号: 15590272
• 负责人: MACHIDE Mitsuru
• 金额: $ 2.18万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15590272/
• 关键词: tissue injury; HGF; c-Met; cell-cell contact; tyrosine phosphatase; oxidant stress; aminoacid; HGF(肝細胞増殖因子); 組織恒常性; juxtamembrane領域; protein kinase C; チロシンキナーゼ; ストレス; 発癌

In this project, we attempted to clarify the molecular mechanisms by which the tissues recognize their injured- or homeostatic states. We especially focused on the physiological changes of activation states of c-Met, the receptor for HGF and obtained the results as descried bellow 1〜4.1, (1) HGF readily induces cellular proliferation of primary hepatocytes when they are cultured at low cellular density, but in confluent cultures, HGF failed to show the effect. which was thought to mimic the response of parenchymal) hepatocytes in injured liver. In this system, we found that c-Met tyrosine autophosphorylation was down regulated in the confluent cells even after HGF-stimulation. (2) Oxidant stress causes arrest of cellular proliferation, and we found that the stress induced by hydrogen peroxide deprives cells of mitotic response to HGF, which was caused down regulation of c-Met activation through Ser985-phosphorylation on c-Met. (3) Primary hepatocytes could not proliferate in proline-free culture medium even after HGF-stimulation, while the c-Met and the associated signal transducers were readily activated.2, We successfully identified molecules responsible for 1,(1)〜 (3) as follows. (1) A tyrosine phosphatase LAR, which dephosphorylates c-Met in a cell density dependent way, (2) PKC enhances Ser985 phosphorylation and PP2A which targets phosphorylated Ser985 was suppressed by hydrogen peroxide-treatment, (3) Expression of CDK4 that trigger the cellular proliferation was suppressed under Pro-free medium.3, We established ES cells for construction of transgenic mouse carrying Ser985 deleted c-Met.

在这个项目中，我们试图阐明组织识别其损伤或稳态的分子机制。本实验着重研究了肝细胞生长因子受体c-Met激活状态的生理变化，得到如下结果：（1）肝细胞生长因子在低密度培养时能促进原代肝细胞增殖，而在汇合培养时不能促进原代肝细胞增殖;其被认为模拟了损伤肝脏中实质肝细胞的反应。在这个系统中，我们发现，c-Met酪氨酸自磷酸化下调融合细胞，即使在HGF刺激。(2)氧化应激导致细胞增殖停滞，我们发现过氧化氢诱导的应激剥夺了细胞对HGF的有丝分裂反应，这是通过c-Met上的Ser 985-磷酸化下调c-Met的活化引起的。(3)原代肝细胞即使在HGF刺激后也不能在无脯氨酸的培养基中增殖，而c-Met和相关的信号转导分子很容易被激活。2，我们成功地鉴定了负责1，（1）β（3）的分子如下。(1)酪氨酸磷酸酶LAR以细胞密度依赖的方式使c-Met去磷酸化;（2）PKC促进Ser 985的磷酸化，而磷酸化Ser 985的PP 2A被过氧化氢处理所抑制;（3）在无Pro培养基中，触发细胞增殖的CDK 4的表达被抑制。

项目成果

町出 充, 中村 敏一: "増殖因子の臨床応用 -HGFによる再生医療の展開-"現代医療. 35(7). 140-148 (2003)

Mitsuru Machide、Toshikazu Nakamura：“生长因子的临床应用 - 使用 HGF 的再生医学的发展 -”现代医学 35(7)。

橋ヶ迫 敦子 et al.: "HGFによる難治性肝疾患の再生治療"血液・免疫・腫瘍. 8(1). 44-51 (2003)

Atsuko Hashigasako 等人：“使用 HGF 进行顽固性肝脏疾病的再生治疗”，血液学、免疫学和肿瘤学 8(1) (2003)。

-HGFによる肝再生医療の展開-

-利用HGF开发肝脏再生医学-

• 发表时间: 2003
• 期刊: G.I.Research (Journal of Gastrointestinal Research) 11
• 作者: Hashigasako A. et al.;Hashigasako A. et al.;Hashigasako A.et al.;Mizuno S.et al.;Yoshida S.et al.;Ohuchida K.et al.;Oshima K.et al.;Koibuchi K.et al.;町出 充 他
• 通讯作者: 町出 充 他

Essential role of HGF (hepatocyte growth factor) in blood formation in Xenopus.

HGF（肝细胞生长因子）在非洲爪蟾血液形成中的重要作用。

• 发表时间: 2004
• 期刊: Blood 103
• 作者: Kuwano H;et al.;森本兼曩;Koibuchi K. et al.
• 通讯作者: Koibuchi K. et al.

Bi-directional regulation of c-met Ser985 phosphorylation via PKC and protein phosphatase 2A involves c-met activation and cellular responsiveness to HGF.

通过 PKC 和蛋白磷酸酶 2A 对 c-met Ser985 磷酸化的双向调节涉及 c-met 激活和细胞对 HGF 的反应。

• 发表时间: 2004
• 期刊: J.Biol.Chem. 279
• 作者: Hashigasako A. et al.