Expression of p57kip2, Rb protein and PCNA and their relationships with clinicopathology in human pancreatic cancer

AIM: To investigate the effects of inhibiting factor of cell cycle regulation p57(kip2), retinoblastinoma protein (Rb protein) and proliferating cell nuclear antigen (PCNA) in the genesis and progression of human pancreatic cancer. METHODS: The expression of p57(kip2), Rb protein and PCNA in tumor tissues and adjacent tissues of 32 patients with pancreatic cancer was detected with SP immunohistochemical technique. RESULTS: p57(kip2) protein positive-expression rate in tumor tissues of pancreatic cancer was 46.9 %, which was lower than that in adjacent pancreatic tissues (75.0 %) (chi(2)=5.317, P<0.05), p57(kip2) protein positive-expression correlated significantly with tumor cell differentiation (well-differentiation versus moderate or low-differentiation, P<0.05) but did not correlate significantly with lymph node metastasis (lymph node metastasis versus non-lymph node metastasis, P>0.05); Rb gene protein positive-expression rate in tumor tissues was 50.0 %, which was also lower than that in adjacent pancreatic tissues (78.1 %) (chi(2)=5.497, P<0.05); PCNA positive-expression rate was 71.9 %, being higher than that in adjacent pancreatic tissues (43.8 %) (chi(2)=5.189, P<0.05), PCNA positive-expression also correlated significantly with tumor cell differentiation and lymph node metastasis (well-differentiation versus moderate or low- differentiation, lymph node metastasis versus non-lymph node metastasis, P<0.05). Rb protein positive-expression rate in the tumor tissues of p57(kiP2) protein positive-expression group was 53.3 %; and Rb protein positive-expression rate in the tumor tissues of p57(kip2) protein negative-expression group was 47.1 %. There was no significant relationship between the two groups (r=0.16507, P>0.05). CONCLUSION: The decreased expression of p57(kip2), Rb protein or over-expression of PCNA protein might contribute to the genesis or progression of pancreatic cancer, p57(kip2), Rb protein and PCNA may play an important role in genesis and progression of pancreatic cancer.