Expression of gap junction genes connexin 32, connexin 43 and their proteins in hepatocellular carcinoma and normal liver tissues

AIM To investigate the significance and mechanism of cx32 mRNA, cx43 mRNA and their proteins in hepatocarcinogenesis.METHODS Sixty-one cases of HCC and 14 cases of normal liver tissues were detected by immunohistochemical and in situ hybridization (ISH) methods.RESULTS In HCC grades Ⅰ,Ⅱ,Ⅲ*and normal liver tissues, the positive rates of Cx32 protein were 55.6%, 42.1%, 18.2% and 92.9%,respectively. The detection rates of Cx43 protein were 44.4%, 26.3%, 12.1% and 78.6%,respectively. There was significant difference in Cx32 and Cx43 protein between HCC and normal liver tissues (P＜0.01). ISH the positive rates of cx32 mRNA shown by ISH in HCC grades Ⅰ,Ⅱ,Ⅲ* and normal liver tissues were 88.9%, 84.2%,87.9% and 92.9%, respectively. Those of cx43 mRNA were 77.8%, 78.6%, 78.8% and 85.7%,respectively. There was no statistical difference in the positive rates of cx32 mRNA and cx43 mRNA between HCC and normal liver tissue (P＞0.05).CONCLUSION The aberrant location of Cx32 and Cx43 proteins could be responsible for progression of hepatocarcinogenesis, and the defect of cx genes in post-translational processing might be the possible mechanism.