Moreno-Manzano V, Lucio-Cazana J, Konta T, Nakayama K, Kitamura M
Department of Medicine, University College Medical School, University College London, Mortimer Street, London, W1T 3AA, United Kingdom.
Biochem Biophys Res Commun. 2000 Oct 22;277(2):293-8. doi: 10.1006/bbrc.2000.3654.
Extracellular matrix facilitates anchorage-dependent cell survival via interaction of its arginine-glycine-aspartate (RGD) motif with integrins. In this report, we describe an unexpected, apoptosis-promoting the effect of immobilized RGD (iRGD) on tumor necrosis factor-alpha (TNF-alpha)-induced apoptosis. Mesangial cells cultured on RGD-coated plates showed enhanced susceptibility to TNF-alpha-induced apoptosis. iRGD alone did not affect cell survival. In contrast, iRGD did not facilitate but inhibited apoptosis induced by H(2)O(2). Mitogen-activated protein (MAP) kinases and tyrosine kinases are important mediators for the RGD-integrin signaling. Pretreatment with MAP kinase kinase inhibitor PD098059, c-Jun N-terminal kinase (JNK)-c-Jun/AP-1 inhibitor curcumin or p38 MAP kinase inhibitor SB203580 did not attenuate the apoptosis-promoting effect of iRGD. Consistently, transfection with dominant-negative mutants of extracellular signal-regulated kinases, JNK or p38 MAP kinase did not inhibit the effect of iRGD. In contrast, protein tyrosine kinase inhibitors, genistein, and herbimycin A, abrogated the apoptosis-promoting effect of iRGD. Of note, TNF-alpha-induced apoptosis on uncoated plates was not attenuated by tyrosine kinase inhibitors. These data provide the first evidence that iRGD accelerates certain apoptosis. We identified that the effect was mediated by the tyrosine kinase-dependent, MAP kinase-independent mechanism.
细胞外基质通过其精氨酸 - 甘氨酸 - 天冬氨酸（RGD）基序与整合素的相互作用促进锚定依赖性细胞存活。在本报告中，我们描述了固定化RGD（iRGD）对肿瘤坏死因子 - α（TNF - α）诱导的细胞凋亡具有意想不到的促凋亡作用。在RGD包被的平板上培养的系膜细胞对TNF - α诱导的细胞凋亡敏感性增强。单独的iRGD不影响细胞存活。相反，iRGD不促进但抑制由H₂O₂诱导的细胞凋亡。丝裂原活化蛋白（MAP）激酶和酪氨酸激酶是RGD - 整合素信号传导的重要介质。用MAP激酶激酶抑制剂PD098059、c - Jun N端激酶（JNK） - c - Jun/AP - 1抑制剂姜黄素或p38 MAP激酶抑制剂SB203580预处理并不能减弱iRGD的促凋亡作用。同样，用细胞外信号调节激酶、JNK或p38 MAP激酶的显性负突变体转染也不能抑制iRGD的作用。相反，蛋白酪氨酸激酶抑制剂染料木黄酮和除莠霉素A消除了iRGD的促凋亡作用。值得注意的是，酪氨酸激酶抑制剂不能减弱未包被平板上TNF - α诱导的细胞凋亡。这些数据提供了第一个证据，即iRGD加速某些细胞凋亡。我们确定该作用是由酪氨酸激酶依赖性、MAP激酶非依赖性机制介导的。
