Adhesion of HT-29 colon carcinoma cells to endothelial cells requires sequential events involving E-selectin and integrin β4
Adhesion of HT-29 colon carcinoma cells to endothelial cells requires sequential events involving E-selectin and integrin β4
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DOI：
10.1023/b:clin.0000037708.09420.9a
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发表时间：
2004-01-01
影响因子：
4
通讯作者：
Huot, J
中科院分区：
文献类型：
--
作者：
Lafferrière, J;Houle, F;Huot, J
HT-29结肠癌细胞通过其与E-选择素的特异性结合而附着于TNFa活化的人脐静脉内皮细胞（HUVEC）。这种相互作用在癌细胞中激活MAPK SAPK 2/p38，这导致它们的跨内皮迁移（Laferriere等人，J Biol Chem 2001; 276：33762）。在这项研究中，我们研究了E-选择素在激活整合素调节粘附和调节整合素介导的事件中的作用。用特异性抗体阻断来自HT-29细胞的整合素（α 2、α 3、α 6、α v β 5、β 1和β 4）揭示了β 4整合素在它们与TNF α处理的HUVEC的粘附中的作用。β 4整合素依赖的粘附是最大的30分钟后，而-E-选择素依赖的粘附是最大的15分钟后。整合素β 4成为快速磷酸化后加入HT-29细胞的内皮细胞和效果是独立的E-选择素的表达。此外，重组E-选择素/Fc嵌合体不诱导α 4的磷酸化。β 4的磷酸化不是粘附所必需的，因为在表达从其胞质磷酸化结构域缺失的截短形式的β 4的HT-29细胞中粘附不受影响。然而，β 4的非磷酸化缺失体的表达与减少的跨内皮细胞迁移相关，强调了β 4的胞质结构域在细胞迁移中的关键作用。我们建议：1）HT-29细胞与活化的内皮细胞的粘附遵循至少两个基本的顺序步骤，包括E-选择素与癌细胞上的其受体结合，然后β 4与内皮细胞上的其自身受体结合; 2）整联蛋白β 4的磷酸化有助于增强癌细胞的运动潜能并增加其跨内皮迁移。总的来说，我们的研究结果表明，转移性癌细胞与内皮细胞的相互作用意味着一个特定的信号事件序列，最终导致其有效的跨内皮迁移的增加。
HT-29 colon carcinoma cells attach to TNFalpha-activated human umbilical vein endothelial cells (HUVECs) by their specific binding to E-selectin. This interaction activates, in the cancer cells, the MAPK SAPK2/p38, which leads to their transendothelial migration (Laferriere et al., J Biol Chem 2001; 276: 33762). In this study, we investigated the role of E-selectin in activating integrins to modulate adhesion and regulate integrin-mediated events. Blocking the integrins from HT-29 cells (alpha2, alpha3, alpha6, alphavbeta5, beta1 and beta4) with specific antibodies revealed a role for beta4 integrin in their adhesion to TNFalpha-treated HUVEC. The beta4 integrin-dependent adhesion was maximal after 30 min, whereas the-E-selectin-dependent adhesion was maximal after 15 min. Integrin beta4 became quickly phosphorylated upon addition of HT-29 cells to endothelial cells and the effect was independent of the expression of E-selectin. Moreover, a recombinant E-selectin/Fc chimera did not induce the phosphorylation of alphabeta4. The phosphorylation of beta4 is not required for adhesion since adhesion was not affected in HT-29 cells that express a truncated form of beta4 that is deleted from its cytoplasmic phosphorylatable domain. However, the expression of the non-phosphorylatable deletant of beta4 was associated with decreased transendothelial cell migration underscoring the key role for the cytoplasmic domain of beta4 in cell migration. We suggest: 1) that the adhesion of HT-29 cells to activated endothelial cells follows at least two essential sequential steps involving the binding of E-selectin to its receptor on carcinoma cells and then the binding of beta4 to its own receptor on endothelial cells; 2) that the phosphorylation of integrin beta4 contributes to enhance the motile potential of cancer cells and increase their trans-endothelial migration. Overall, our results indicate that the interaction of metastatic cancer cells with endothelial cells implies a specific sequence of signaling events that ultimately leads to an increase in their efficient transendothelial migration.