LINC00473 promotes hepatocellular carcinoma progression via acting as a ceRNA for microRNA-195 and increasing HMGA2 expression

Abstract

Hepatocellular carcinoma (HCC) is a most aggressive malignant tumor. Nevertheless, the molecular mechanisms underlying HCC are still completely unclear. LINC00473 is identified as a tumor promoter in many cancers. In this investigation, the function of LINC00473 was specifically focused on. We exhibited that LINC00473 was obviously elevated in HCC cells compared to QSG-7701 cells. Functionally, down-regulation of LINC00473 could prevent HCC cell viability and cell proliferation. For another, HCC cell colony formation capacity was greatly restrained while cell apoptosis was triggered by loss of LINC00473. Meanwhile, would-healing assay and transwell invasion experiments were employed in our present study. As demonstrated, we observed that HCC cell migratory and invasive ability were obviously suppressed by the silence of LINC00473. Apart from these, mechanistic investigations implied miR-195 was a sponge target of LINC00473. It is widely established miR-195 is a famous tumor inhibitory gene regulator in various cancers. Here, we confirmed the binding correlation between LINC00473 and miR-195 using RIP assay. Subsequently, in vivo experiments were employed and it was manifested that LINC00473 was able to promote HCC tumor growth via acting as a ceRNA to inhibit miR-195. HMGA2 is a kind of nuclear-binding protein and it is involved in various cancers. We predicted it as a target of miR-195 and we confirmed their correlation. In addition, HMGA2 was repressed by loss of LINC00473, which was rescued by miR-195 inhibitors. Then, we found that angiogenic fator vascular endothelial growth factor (VEGF) was inhibited by loss of LINC00473 whereas anti-angiogenic factor EPN2 was induced in vivo. Taken all these together, our study revealed the significance of LINC00473/miR-195/HMGA2 signaling axis for the first time in HCC progression. It was suggested the potential possibility of LINC00473 as an indicator for HCC.