MYO18B promotes hepatocellular carcinoma progression by activating PI3K/AKT/mTOR signaling pathway

BACKGROUND: MYO18B has been identified as a novel tumor suppressor gene in several cancers. However, its specific roles in the progression of hepatocellular carcinoma (HCC) has not been well defined. METHODS: We firstly identified the expression and prognostic values of MYO18B in HCC using TCGA cohort and our clinical data. Then, MYO18B knockdown by RNA inference was implemented to investigate the effects of MYO18B on HCC cells. Quantitative RT-PCR and Western blot were used to determine gene and protein expression levels. CCK-8 and colony formation assays were performed to examine cell proliferation capacity. Wound healing and transwell assays were used to evaluate the migration and invasion of HepG2 cells. RESULTS: MYO18B was overexpressed and correlated with poor prognosis in HCC. MYO18B expression was an independent risk factor for overall survival. Knockdown of MYO18B significantly inhibited the proliferation, migration and invasion of HepG2 cells. Meanwhile, MYO18B knockdown could effectively suppress the phosphorylation of PI3K, AKT, mTOR and P70S6K, suggesting that MYO18B might promote HCC progression by targeting PI3K/AKT/mTOR signaling pathway. CONCLUSIONS: MYO18B promoted tumor growth and migration via the activation of PI3K/AKT/mTOR signaling pathway. MYO18B might be a promising target for clinical intervention of HCC.