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 cellcycle regulation p57kip2,retinoblastinoma protein(Rb protein)and proliferating cell nuclear antigen(PCNA)in the genesisand progression of human pancreatic cancer.METHODS:The expression of p57kip2,Rb protein and PCNAin tumor tissues and adjacent tissues of 32 patients withpancreatic cancer was detected with SP immunohistochemicaltechnique.RESULTS:p57kip2protein positive-expression rate in tumortissues of pancreatic cancer was 46.9 %,which was lowerthan that in adjacent pancreatic tissues(75.0 %)(X~2=5.317,P<0.05),p57kip2protein positive-expression correlatedsignificantly with tumor cell differentiation(well-differentiationversus moderate or low-differentiation,P<0.05)but did notcorrelate significantly with lymph node metastasis(lymph nodemetastasis versus non-lymph node metastasis,P>0.05);Rbgene protein positive-expression rate in tumor tissues was50.0 %,which was also lower than that in adjacent pancreatictissues(78.1%)(X~2=5.497,P<0.05);PCNA positive-expression rate was 71.9 %,being higher than that inadjacent pancreatic tissues(43.8 %)(X~2=5.189,P<0.05),PCNA positive-expression also correlated significantly withtumor cell differentiation and lymph node metastasis(well-differentiation versus moderate or low-differentiation,lymphnode metastasis versus non-lymph node metastasis,P<0.05).Rb protein positive-expression rate in the tumor tissues ofp57kip2protein positive-expression group was 53.3 %;andRb protein positive-expression rate in the tumor tissues ofp57kip2protein negative-expression group was 47.1%.Therewas no significant relationship between the two groups(r=0.16507,P>0.05).CONCLUSlrON:The decreased expression of p57kip2,Rbprotein or over-expression of PCNA protein might contributeto the genesis or progression of pancreatic cancer,p57kip2,Rb protein and PCNA may play an important role in genesisand progression of pancreatic cancer.