Department of Gastroenterology, The Ninth People's Hospital Affiliated to the School of Medicine, Shanghai Jiao Tong University, Shanghai 200011, China.
Department of Gastroenterology, The Ninth People's Hospital Affiliated to the School of Medicine, Shanghai Jiao Tong University, Shanghai 200011, China.
Biomed Pharmacother. 2017 Sep;93:1025-1032. doi: 10.1016/j.biopha.2017.07.029. Epub 2017 Jul 17.
Emerging reports suggest microRNAs (miRNAs) play a vital role in the progression of malignant tumors. MiR-30a is downregulated in a variety of cancers and acts as a tumor suppressing gene. However, the molecular mechanisms of miRNA-30a in hepatocellular carcinoma (HCC) are still unclear. Hereby, in this study, we detected that miR-30a expression was significantly down-regulated in both HCC tissues compared with adjacent non-cancerous liver tissues, and we also observed that miR-30a expression was lower in HCC cell lines than that of normal controls. By overexpression of miRNA-30a, we evaluated cell growth with CCK-8 assay and cell apoptosis by flow cytometry. The function of miR-30a on cellular migration in HCC cells was assessed. The potential target genes of miR-30a were analyzed with luciferase activity assay. Our data displayed that miR-30a mimic markedly inhibited HCC cell growth, induced cell apoptosis, and upregulated the expression of apoptotic proteins in HepG2 and MHCC976L cells. We also found that upregulation of miR-30a significantly inhibited HCC cells migration and invasion. Bioinformatics analysis revealed K-Ras was a regulative target gene of miR-30a, and further dual luciferase reporter assay showed that miR-30a directly binds to the 3'-untranslated region (3'-UTR) of K-Ras mRNA. Furthermore, we found that in HepG2 and MHCC97L cancer cells, miR-30a overexpression completely blocked the K-Ras/c-Raf/MEK/ERK pathway activation. Overall, these findings demonstrated that miR-30a might play a certain role in the cell growth, apoptosis and metastasis of HCC cells, partially via regulating K-Ras/c-Raf/MEK/ERK signaling pathway, potentially, it is therefore a candidate targeting biomarker for HCC therapy.
新兴研究报告表明，microRNAs（miRNAs）在恶性肿瘤的进展中起着至关重要的作用。miR-30a 在多种癌症中下调，充当肿瘤抑制基因。然而，miRNA-30a 在肝细胞癌（HCC）中的分子机制尚不清楚。在本研究中，我们检测到 HCC 组织中 miR-30a 的表达明显低于相邻非癌性肝组织，并且还观察到 HCC 细胞系中的 miR-30a 表达低于正常对照。通过过表达 miRNA-30a，我们使用 CCK-8 测定法评估细胞生长，并用流式细胞术评估细胞凋亡。评估了 miR-30a 对 HCC 细胞中细胞迁移的功能。使用荧光素酶活性测定分析了 miR-30a 的潜在靶基因。我们的数据显示，miR-30a 模拟物明显抑制 HCC 细胞生长，诱导细胞凋亡，并上调 HepG2 和 MHCC976L 细胞中凋亡蛋白的表达。我们还发现上调 miR-30a 可显着抑制 HCC 细胞的迁移和侵袭。生物信息学分析表明 K-Ras 是 miR-30a 的调节靶基因，进一步的双荧光素酶报告基因测定显示 miR-30a 可直接结合 K-Ras mRNA 的 3'-非翻译区（3'-UTR）。此外，我们发现 miR-30a 在 HepG2 和 MHCC97L 癌细胞中过表达可完全阻断 K-Ras/c-Raf/MEK/ERK 通路的激活。总的来说，这些发现表明 miR-30a 可能在 HCC 细胞的生长，凋亡和转移中发挥一定作用，部分通过调节 K-Ras/c-Raf/MEK/ERK 信号通路，因此，它可能是 HCC 治疗的候选靶向生物标志物。
