CASC2/miR-18a/BTG3信号抑制非小细胞肺癌迁移和侵袭

CASC2/miR-18a/BTG3 signaling inhibits cell migration and invasion of non-small cell lung cancer

目的:研究长链非编码RNA CASC2在非小细胞肺癌(NSCLC)细胞迁移和侵袭中的作用及调控机制。方法: RT-qPCR和Western blot法检测正常人支气管上皮细胞系16-HBE及NSCLC细胞系A549和H1299中CASC2、微小RNA-18a (miR-18a)和BTG3的表达;生物信息学预测CASC2和miR-18a及miR-18a和BTG3的靶向关系,并利用双萤光素酶报告基因实验加以验证;Transwell小室法检测NSCLC细胞的迁移和侵袭能力;RT-qPCR和Western blot测定CASC2对miR-18a和BTG3表达的调控。结果:与16-HBE细胞相比,CASC2和BTG3在NSCLC细胞系中表达量明显下调,而miR-18a出现明显的高表达( P<0.05 );CASC2能够靶向吸附miR-18a,且 BTG3 被证实是miR-18a的一个靶基因;CASC2过表达抑制NSCLC细胞的迁移和侵袭能力,但外源回补miR-18a可促进细胞的迁移和侵袭;外源回补miR-181a可逆转CASC2对BTG3蛋白表达的促进作用。结论: CASC2通过负调控miR-18a促进BTG3表达,进而抑制NSCLC细胞的迁移和侵袭。

AIM: To explore the function and molecular mechanism of long non-coding RNA CASC2 in non-small-cell lung cancer (NSCLC) cell migration and invasion. METHODS: RT-qPCR and Western blot were used to detect the expression of CASC2, microRNA-18a (miR-18a) and BTG3 in human bronchial epithelial cell line 16-HBE, and NSCLC cell lines A549 and H1299. The interaction between CASC2 and miR-18a or miR-18a and BTG3 was predicted by bioinformatics software and verified by double-luciferase reporter assays. Transwell assays were performed to detect the migration and invasion abilities of the NSCLC cells. RT-qPCR and Western blot were used to determine the regulatory effects of CASC2 on miR-18a and BTG3 expression. RESULTS: Compared with 16-HBE cells, the expression of CASC2 and BTG3 was significantly down-regulated in the NASCL cells, while miR-18a was significantly over-expressed ( P <0.05). CASC2 acted as a molecular sponge for miR-18a, and BTG3 was verified to be a target gene of miR-18a. Up-regulation of CASC2 inhibited the migration and invasion abilities of NSCLC cells, while exogenous restoration of miR-18a stimulated cell migration and invasion abilities. In addition, exogenously over-expressed miR-181a reversed the promoting effect of CASC2 on BTG3 protein expression. CONCLUSION: CASC2 promotes BTG3 expression by negatively regulating miR-18a, and then inhibits the migration and invasion abilities of NSCLC cells.