Downregulated Expression of Chromobox Homolog 7 in Hepatocellular Carcinoma

Background: As an essential member of the Polycomb group (PcG) proteins, chromobox homolog 7 (CBX7) is found deregulated in some human cancers, and is thought to be a contributing factor in carcinogenesis. However, the expression and role of CBX7 in hepatocellular carcinoma (HCC) is still not well characterized. Materials and Methods: The levels of the CBX7 protein were quantified in 75 paired HCC and adjacent nontumor tissues by immunohistochemistry; comparisons were made using McNemar's chi-square test. The Kaplan–Meier estimate was used for survival analysis. Results: We found that the expression of CBX7 in HCC tissues was significantly lower than that of adjacent nontumor tissues. In addition, decreased CBX7 expression levels were correlated with liver cirrhosis in HCC patients. Furthermore, the survival times of HCC patients who were CBX7-expression-negative were shorter than HCC patients who were CBX7-expression-positive. Conclusion: Our results show that downregulation of CBX7 is related to HCC progression and a poor prognosis in HCC patients.