MicroRNA-506 suppresses invasiveness and metastasis of human hepatocellular carcinoma cells by targeting IL8.

MicroRNAs (miRNAs) have been reported to be involved in tumor metastasis. In this study, we investigated the function of miR-506 in the metastasis of human hepatocellular carcinoma (HCC). We found that miR-506 is significantly downregulated in the primary tissue of metastatic HCC and in highly metastatic HCC cell lines. Overexpression of miR-506 suppressed HCC cell migration, invasion, and metastasis both in vitro and in vivo. Furthermore, miR-506 was found to specifically target the 3' untranslated region (3'-UTR) of interleukin 8 (IL8) mRNA. Spearman's correlation analysis revealed that miR-506 expression inversely correlated with IL8 mRNA and protein expression in HCC tissue samples. IL8 treatment reversed miR-506-induced suppression of HCC cell migration and invasiveness. Thus, miR-506 acts as a tumor suppressor that may inhibit the migration, invasiveness, and metastasis of HCC cells by targeting IL8.