PLK4 is overexpressed in hepatocellular carcinoma; its overexpression promotes cell proliferation, migration and invasion, while downregulation suppresses these cell behaviors; high PLK4 expression is associated with shorter overall and disease-free survival in patients [33, 34]. Other studies suggest that PLK4 mRNA and protein levels are decreased in hepatocellular carcinoma compared with noncancerous tissues and that the lower levels are associated with poorer clinicopathological and shorter survival parameters; PLK4 silencing increases cell growth in vitro [35, 36]. This evidence concerns the gene PLK4 and hepatocellular carcinoma.