Clinical significance of p16 protein expression loss and aberrant p53 protein expression in pancreatic cancer.
Pancreatic cancer is a disease with poor prognosis mainly due to low resection rates and late diagnosis. To increase resectability and improve survival rates, a better understanding of pancreatic cancer pathogenesis and more effective screening techniques are required. New methods, such as genetic and molecular alterations, may suggest novel approaches for pancreatic cancer diagnosis and treatment. We immunohistochemically investigated 44 formalin-fixed, paraffin-embedded specimens of pancreatic ductal adenocarcinoma using monoclonal anti-p16 antibodies and monoclonal anti-p53 antibodies. The expressions of p16 and p53 proteins were compared using the Chi-square test with SPSS. Disease-free survival was analyzed using the Kaplan-Meier method, verified by the Log- Rank test. Loss of p16 expression was noted in 20 (45.5%) cases and aberrant p53 protein expression was detected in 14 (31.8%) cases. Loss of p16 expression was associated with a higher incidence of lymph node metastasis (p=0.040) and a more advanced stage (p=0.015), although there was no significant correlation between p16 expression and survival. Aberrant p53 protein expression correlated with histologic grade (p= 0.038). Disease-free survival rate was significantly lower in the aberrant p53 protein positive group compared to the negative group (p=0.029). From our results, we suggest that p53 is not a prognostic factor; however, p16 and p53 genes do play important roles in the progression of pancreatic ductal adenocarcinoma.
Jeong
Joon
J
Department of Surgery, Yongdong Severance Hospital, Yonsei University College of Medicine, 146-92 Dogok-dong, Kangnam-gu, Seoul 135- 720, Korea.
Park
Young Nyun
YN
Park
Joon Seong
JS
Yoon
Dong-Sup
DS
Chi
Hoon Sang
HS
Kim
Byong Ro
BR
D000328:Adult; D000368:Aged; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis*; D005260:Female; D019942:Genes, p16; D016158:Genes, p53; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000737:chemistry* / Q000235:genetics / Q000401:mortality / Q000473:pathology; D012727:Sex Characteristics; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
D019941:Cyclin-Dependent Kinase Inhibitor p16; D016159:Tumor Suppressor Protein p53