Metallothionein 1M suppresses tumorigenesis in hepatocellular carcinoma

Members of the metallothionein (MT) family are involved in metal detoxifcation and in the protection of cells against certain electrophilic carcinogens. In present study, it was found that MT1M was downregulated in more than 77.1% (91/118) of hepatocellular carcinoma (HCC) tissues compared with adjacent non-tumor tissues. Furthermore, overexpression of MT1M inhibited cell viability, colony formation, cell migration and invasion in HCC cell lines and tumor cell growth in xenograft nude mice, and activated cell apoptosis in HCC cell lines. In addition, immunohistochemistry analysis showed MT1M was negative or weak staining in tumor tissues but moderate or strong staining in adjacent non-tumor tissues. The sensitivity and specificity of MT1M for HCC diagnosis were 76.27% and 89.83%, respectively. In conclusion, MT1M was identified as a potential tumor marker for HCC and may serve as a useful therapeutic agent for HCC gene therapy.