Long non-coding RNA CASC15 promotes HCC progression via modulation of Six1 targeted by miR-2355-5p

Abstract Background: Long-chain non-coding RNA (LncRNA) plays a key role in the biological processes of tumors. LncRNA CASC15 has been shown to be involved in the development of a variety of tumors. The study aimed to elucidate the mechanism of lncRNA CASC15 in the progression of hepatocellular carcinomas (HCC).Methods: qRT-PCR was used to detect the expression levels of CASC15, miR-2355-5p and Six1 mRNA in HCC tissues and cells. Six1 protein expression levels were detected by Western Blot. CCK-8 experiment, colony formation experiment, Edu staining and Transwell experiment analysis were used to analyze the effects of CASC15, miR-2355-5p and Six1 on cell proliferation, cell invasion and migration. The relationship between CASC15, miR-2355-5p and Six1 was analyzed using bioinformatics analysis and Luciferase.Result: CASC15 was raised in HCC tissues and HCC cells. Down-regulation of CASC15 inhibited the growth, migration, invasion and tumor growth of HCC cells. The expression level of miR-2355-5p was reduced in HCC tissues. In addition, miR-2355-5p inhibitor induced the growth, migration and invasion of HCC cells. MiR-2355-5p was predicted to be a downstream target of CASC15. The expression level of miR-2355-5p was negatively correlated with CASC15 in HCC tumor tissues. Six1 was predicted to be a downstream target of miR-30a-5p. In vitro and in vivo results showed that CASC15/miR-2355-5p can regulate Six1.Conclusion: LncCASC15 regulated the proliferation and invasion of Six1 by binding with miR-2355-5p in HCC, suggesting that CASC15 may be a potential target for HCC.