Background and objective: MicroRNAs (miRNAs) is a group of non-coding small RNA molecules, which play important roles in the development of tumor. The mechanisms of various kinds of miRNAs in lung cancer still need to be further elucidated. This study investigated the function of miR-614 on lung cancer cell invasion and proliferation.
Methods: Real-time quantitative PCR was used to detect the expression of miR-614 in lung cancer cell PGCL3 and PGLH7. Transwell assay was used to test the role of miR-614 on regulating invasion and migration of cells. CCK8 assay and BrdU incorporation assay was used to assess the role of miR-614 on cell proliferation. Bioinformatics software predicted the potential target genes of miR-614 and dual luciferase reporter gene was used to analyze the binding between miR-614 and 3'UTR of puromycin-sensitive aminopeptidase (PSA). Western blot detected the PSA protein levels.
Results: The expression of miR-614 in PGCL3 cells with high metastasis potential was significantly lower than that in PGLH7 cells with low metastasis potential. Furthermore, altered expression of miR-614 by transfection of pre-miR-614 mimics and inhibitor significantly affected the ability of invasion and proliferation of lung cancer cells. Bioinformatics analysis predicted that PSA was one of the potential target genes of miR-614. Altered expression of miR-614 markedly down-regulated the PSA protein levels of lung cancer cells. In addition, dual luciferase reporter gene assay indicated that miR-614 regulated PSA expression by binding to the 3'UTR of PSA mRNA.
Conclusions: MiR-614 inhibited cell invasion and proliferationa targeting PSA in lung cancer cells, PGCL3.
背景与目的 MicroRNAs（miRNAs）是一种非编码的小分子RNA，在肿瘤的发生发展过程中发挥着重要的作用，各种miRNAs对肺癌的作用及机制仍需进一步阐明。本研究探讨了miR-614对肺癌细胞增殖和侵袭的作用及机制。方法 应用实时定量PCR检测miR-614在高低不同转移能力肺癌PGCL3和PGLH7细胞中的表达水平；脂质体2000介导分别转染miR-614类似物和抑制物入PGCL3和PGLH7细胞，应用Transwell实验检测miR-614对肺癌细胞侵袭的作用；应用CCK8实验和BrdU掺入实验检测miR-614对肺癌细胞增殖的作用；生物信息学软件预测miR-614潜在的靶基因，双荧光素酶报告基因验证miR-614是否作用于嘌呤霉素敏感性氨肽酶（puromycin-sensitive aminopeptidase, PSA）mRNA的3’UTR区预测靶位；Western blot检测PSA蛋白水平。结果 miR-614在高转移肺癌细胞PGCL3中的表达水平明显低于其在低转移肺癌细胞PGLH7的表达水平；体外侵袭实验结果显示，miR-614可抑制肺癌细胞侵袭；细胞增殖实验结果显示，miR-614可抑制肺癌细胞增殖；miRanda软件预测并经双荧光素酶报告基因验证PSA是miR-614的靶基因；miR-614类似物可下调PSA蛋白表达，miR-614抑制物可上调PSA蛋白表达。结论 miR-614过表达抑制了人肺癌细胞的侵袭和增殖能力，PSA是miR-614下游靶基因之一。