Down-Regulated CMTM2 Promotes Epithelial-Mesenchymal Transition in Hepatocellular Carcinoma

BACKGROUND: Our recent study identified that human chemokine-like factor (CKLF)-like MARVEL transmembrane domain-containing family member 2 (CMTM2) was deregulated in hepatocellular carcinoma (HCC) tissues and posed as a potential tumor suppressor. However, the mechanism of CMTM2 in HCC occurrence and development has not been well elaborated. MATERIALS AND METHODS: The expression of CMTM2 was knocked-down by RNA interruption in Huh-7 and SMMC7721 cells. Cell proliferation ability was detected by CCK8 test and colony formation assay. The cell invasion and migration were measured by wound healing and Transwell assay. RESULTS: We found that the cell proliferation was significantly increased by interruption of CMTM2 expression, both in Huh-7 and SMMC7721 cells. Moreover, down-regulated CMTM2 could promote the invasion and migration ability of HCC cells through inducing the epithelial-mesenchymal transition (EMT) process. We further discovered that both the expression of CMTM2 and the EMT-associated marker E-cadherin were decreased in the same thirty cases of HCC tissues compared with the corresponding adjacent non-tumor tissues. Pearson correlation test showed that there was a significantly positive correlation between CMTM2 and E-cadherin in HCC tissues (P<0.05). CONCLUSION: Based on the results of cell model and HCC tissues, our study suggests that down-regulated CMTM2 promotes HCC metastasis through inducing the EMT process.