ABSTRACT
The purpose of this study was to clarify the association between P53 and the Bcl-2 family [Bcl-2, Bax, Bcl-xL, Bcl-xS] expression and apoptosis in pancreatic ductal adenocarcinoma [PDAC]. A total of 70 patients with PDAC were studied. The expression of P53 protein in PDAC was assessed using the immunohistochemical method, which categorized the PDAC patients into two groups: group 1: 36 cases with immunonegative P53[-], and group 2: 34 cases with immunopositive P53[+]. The expression of Bcl-2, Bax, Bcl-xL, and Bcl-xS in the 70 PDAC cases was detected by immunohistochemical and Western blotting methods. The apoptotic index [AI] was also measured in these samples by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling [TUNEL] method. The relation between P53 and the Bcl-2 protein family and apoptosis was then evaluated. Bcl-2 and Bcl-xS expression was significantly associated with P53 [p<0.05]. No clear associations were found among P53, Bax and Bcl-xL expression [p>0.05]. The AI of groups 1 and 2 was 12.1 +/- 2.47 and 8.1 +/- 1.48, respectively [p=0.023]. There was no relationship between AI and Bcl-2, Bax, Bcl-xL and Bcl-xS expression [p>0.05, respectively]. Bcl-2/Bax ratio was significantly associated with AI [p<0.01]. Bcl-2 and Bcl-xS represent significant anti-and proapoptotic proteins, respectively, modulated through a P53-dependent pathway in PDAC, and P53 modulated apoptosis mainly through Bcl-2/Bax ratio