Expression of mortalin detected in human liver cancer by tissue microarrays.

Mortalin is a highly conserved molecular chaperone in the heat shock protein (HSP) 70 family, which plays a role in carcinogenesis. The relationship between tumors and the expression of mortalin is not fully elucidated. In this study, human tumor specimens from various organs of liver cancer at different stages and cultured liver cancer cells were used to study the expression pattern of mortalin. Through immunohistochemistry we showed that mortalin was significantly higher in tumors than in adjacent benign tissues. Using liver tissue microarrays tested on hepatocellular carcinomas, mortalin expression was consecutively higher with advanced tumor stages. Mortalin expression on the cultured liver cancer cells were characterized with immunocytochemistry, Real-time PCR, and western blot. The results showed that the expression level is markedly higher in the SMMC 7721 (a liver-derived tumor cell line) than in the HL 7702 (a normal liver cell line) in the protein level only. Understanding the role of mortalin in tumors may lead to development of a new therapeutic target in cancer treatment.