miR-34a 通过Snail 诱导肺癌EMT 及促进其转移的分子机制

目的:探讨miR-34a 在肺癌组织中的表达情况以及miR-34a 在肺癌细胞侵袭和迁移过程中的作用及其机制。方法:qPCR 检测肺癌和正常肺组织中miR-34a 的表达情况;使用miR-34a-mimic 和miR-34a-inhibitor 过表达和沉默miR-34a,qPCR 检测沉默和过表达效果;Western blot 检测沉默和过表达miR-34a 后Snail 蛋白的表达情况;荧光素酶报告基因检测miR-34a 与Snail 的相互作用;Transwell 侵袭实验检测miR-34a 的表达对肺癌细胞侵袭能力的影响;划痕实验检测miR-34a 的表达对肺癌细胞迁移能力的影响;Western blot 检测E-Cadherin、Vimentin 和Twist 蛋白的表达情况。结果:与正常肺组织相比,肺癌组织中miR-34a 表达明显降低;且晚期、低分化和有淋巴结转移的肺癌组织miR-34a 表达明显较早期、高分化和无淋巴结转移的肺癌组织低;miR-34a-mimic miR-34a-inhibitor 可以有效抑制和过表达miR-34a 的表达;miR-34a 能与Snail 的3忆UTR 特异性结合;miR-34a 可以调控肺癌H1650 细胞的侵袭迁移能力;过表达miR-34a 上调E-Cadherin,同时下调Vimentin 和Twist 蛋白的表达,沉默miR-34a 则相反。结论:miR-34a 在肺癌中表达明显降低,且跟肺癌分期分级以及淋巴结转移与否密切相关,同时miR-34a 可以通过上皮间质转化调节肺癌细胞侵袭和迁移能力。

Mechanism of miR-34a on invasion and migration ability of human lung carcinoma by Snail induced EMT

Objective:To investigate the exression of miR-34a on lung cancer and normal lung tissues,and the effect and mechanism of miR-34a in lung cancer cell invasion and migration.Methods: qPCR was used to detect the expression of miR-34a on lung cancer.miR-34a-mimic and miR-34a-inhibitor were used to overexpress and knockdown miR-34a.qPCR was used to detect the ef-fectiveness.Western blot was used to detect the expression of Snail after induced with miR-34a-mimic and miR-34a-inhibitor.Luciferase reporter gene was used to detect interaction between miR-34a and Snail.Transwell invasion assay was used to detect invasion ability after induced with miR-34a-mimic and miR-34a-inhibitor.Scratch assay was used to detect migration ability after induced with miR-34a-mimic and miR-34a-inhibitor.The expression of E-cadherin,Vimentin and Twist were detected by Western blot.Results: miR-34a expression was significantly reduced in lung cancer.With the stage of lung cancer progression,the expression of miR-34a reduced.With the differentiation of lung cancer progression,the expression of miR-34a decreased.Decreasing of miR-34a was associated with lung cancer lymph node metastasis.miR-34a-mimic and miR-34a-inhibitor could overexpress and knockdown miR-34a.miR-34a could regulate expression of Snail.Snail was the direct target of miR-34a;miR-34a could regulate the invasion ability of human lung carcinoma H1650 cells;miR-34a could regulate the migration of human lung carcinoma H1650 cells;miR-34a could regulate the expression of E-cadherin,Vimentin and Twist.Conclusion: miR-34a plays the role of tumor suppressor factor in lung cancer.miR-34a can regulate the invasion and migration ability of lung carcinoma H1650 cells by Snail induced EMT.