ROCK 与ET-1 协同促进SLUG 转录诱导上皮性卵巢癌细胞发生上皮向间充质转分化#
 

摘要：目的：ROCK 为RhoGTPases 的下游效应分子，在卵巢癌细胞中过度激活。 内皮素-1（ET-1）和内皮素受体（ETAR）在卵巢癌原发灶和转移灶中表达量高。而且，在卵巢癌患者的腹水中可以检测到ET-1 高表达，表明ET-1 可以促进肿瘤的播散。本实验研究ET-1/ETAR和ROCK 在促进上皮性卵巢癌细胞SK-OV-3 和CaOV3 发生上皮向间充质转分化（EMT）中的作用。方法：ET-1 处理SK-OV-3 和CaOV3 后，用Realtime PCR 和Western blot 等方法检测细胞EMT 的形态和基因变化。结果：发现ET-1 能诱导细胞发生EMT 相一致的形态和基因变化；同时，ET-1 促进SLUG 的转录；而且，ROCK 的活化突变体转染该两种细胞，可以激活ROCK 通路，促进SLUG 启动子活性而上调SLUG 的转录水平，增强ET-1 促进SLUG 转录的作用；ROCK 抑制剂Y27632 可以逆转ET-1 对SLUG 的上调作用。结论：这些结果表明ROCK 协同ET-1 促进SLUG 转录，从而促进上皮性卵巢癌细胞发生EMT。
 

关键词：卵巢癌；ROCK；内皮素-1；SLUG；上皮向间充质转分化

0 引言
因为上皮性卵巢癌容易发生远处转移，它成为妇科恶性肿瘤的首要致死原因。上皮向间充质转型（epithelial-to-mesenchymal transition, EMT）可使癌细胞获得迁移、侵袭和转移的能力, 从而在肿瘤转移中起重要作用。内皮素-1（ET-1）及其受体ETAR 在卵巢癌的原发灶和转移灶中高表达。而且，在肿瘤细胞中，ET-1/ETAR 自分泌通路通过诱导纤维样和侵袭的表型，促进EMT；ROCK 是Rho GTPases 的下游效应分子，可以调节细胞骨架的组装以及细胞黏附斑的形成。但是，在诱导上皮性卵巢癌细胞EMT 发生过程中，ET-1/ETAR 通路与ROCK 的协同作用及可能的机制，目前的研究甚少。本实验以上皮性卵巢癌细胞SK-OV-3和CaOV3 为研究对象，用ET-1 处理或激活ROCK 后，检测其EMT 表型的改变以及转录因子SLUG的转录水平，探讨ET-1/ETAR通路与ROCK协同促进上皮性卵巢癌细胞发生EMT的作用及其机制。

4 结论
总之，本研究揭示了上皮性卵巢癌细胞发生EMT 新的机制：上皮性卵巢癌细胞中ET-1/ETAR 信号诱导ROCK 活化，ROCK 活化后促进下游靶基因SLUG 转录，进而促进上皮性卵巢癌细胞发生EMT 以及转移。因此，抑制ROCK 有可能作为逆转卵巢癌侵袭与转移的一个新的治疗方向。
 

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