Tissue microarray for high-throughput analysis of gene expression profiles in hepatocellular carcinoma

To study the expression profiles of HBsAg, HBcAg, p21WAF1/CIP1 (p21), Rb genes in hepatocellular carcinoma (HCC) and to investigate their roles in the hepatocar-cinogenesis.

HCC tissue microarray containing 120-min tissues of 40 HCC cases was constructed. HBsAg, HBcAg, p21 and Rb proteins were immunohistochemically stained by streptavidin-peroxidase conjugated method (S-P). The expression loss of these genes in cancerous, para-cancerous tissues and adjacent normal liver tissues of 40 HCCs were comparatively examined.

The positive rate of HBsAg expression in cancerous tissues of 40 HCCs was 7.5%, which was lower than that in para-cancerous and adjacent normal liver tissues (chi2 =12.774, P < 0.01; chi2 = 18.442, P < 0.01). The positive rate of HBcAg expression in cancerous tissues of 40 HCCs was 20.0%, which was also lower than that in para-cancerous and adjacent normal liver tissues (chi2 = 9.482, P < 0.01; chi2 = 14.645, P < 0.01). p21 protein deletion rate in cancerous tissues of 40 HCCs was 27.5%, which was higher than that in para-cancerous and adjacent normal liver tissues (chi2 = 7.439, P < 0.01; chi2 = 11.174, P < 0.01). p21 protein deletion correlated remarkably with the pathological grade of HCC (chi2 = 0.072, P < 0.05). Rb protein deletion rate in cancerous tissues of 40 HCCs was 42.5%, which was also higher than that in para-cancerous and adjacent normal liver tissues (chi2 = 10.551, P < 0.01; chi2 = 18.353, P < 0.01). Rb protein deletion rate did not correlate remarkably with tumor size or pathological grade of HCC (chi2 = 0.014, P > 0.05; chi2 = 0.017, P > 0.05).

Expression deletion of HBsAg, HBcAg, p21 and Rb proteins in HCCs may play important roles in the carcinogenesis of HCC. Tissue microarray is an effective high-throughput technique platform for cancer research.