[Expression of cyclins in hepatocellular carcinoma and its correlation to tumor cell apoptosis]

Abstract

Background & objective: Cyclins overexpress in various tumors, but its expression in hepatocellular carcinoma (HCC) and its correlation to cell proliferation and apoptosis are unclear. This study was to determine the expression of Cyclins, proliferating cell nuclear antigen (PCNA), and cell apoptosis in HCC, and to analyze their interrelations.

Methods: Tissue microarray technology and SP immunohistochemistry were used to detect expressions of Cyclins A, B1, D1, E, and PCNA in 122 specimens of HCC. In situ terminal deoxyribonucleotide transferase labeling was used to detect cell apoptosis.

Results: In the 122 HCC specimens, positive rate of Cyclin A was 50.0%, of Cyclin B1 was 47.5%, of Cyclin D1 was 42.6%, of Cyclin E was 35.2%. Cyclins levels were significantly higher in HCC tissues of grade II, III, and IV than in HCC tissues of grade I(P 0.05). Densities of apoptotic cells were significantly lower in HCC tissues of grade II, III, and IV than in HCC tissues of grade I(P 0.05); PCNA scores were significantly higher in HCC tissues of grade II, III, and IV than in HCC tissues of grade I(P 0.01). The poorer differentiation, the lower density of apoptotic cells in HCC, the higher PCNA score in HCC. Cyclins levels were negatively related to density of apoptotic cells (r=-0.686, P < 0.01), and positively related to PCNA score (r=0.599, P < 0.01); density of apoptotic cells was negatively related to PCNA score (r=-0.701, P < 0.01).

Conclusion: Cyclins overexpress in HCC, which may shorten tumor cell cycle phase, accelerate cell proliferation and decrease apoptosis, and result in increased malignant phenotypes.