Prognostic significance of bcl-2 and p53 expression in colorectal carcinoma

Objective： This study was designed to detect the expression ofbcl-2 and p53 proteins in colorectal carcinomas and to determine their association with the patient survival and stage of the diseases. Methods： Immunohistochemistry method was used to detect the expression ofbcl-2 and p53 proteins in 93 cases ofcolorectal carcinoma. The stain results were obtained by analyzing the clinic-pathological characteristics of patients. Results： Fifty-seven percent （53/93） of the colorectal carcinomas were bcl-2 protein positive. The positive rate of bcl-2 protein in lymph node involvement cases was lower （15/37） than the cases without node involvement （38/58, P〈0.01）. The positive rate of p53 protein was 43% （40/93） in colon-rectum carcinomas. No significant correlation was observed between p53 protein expression and clinic-pathological manifestations （P〉0.05） but the survival was significantly worse （P=0.0001） in the p53 protein positive cases. Neither bcl-2 nor p53 alone was correlated with stage of the disease. When combined bcl-2/p53 status was analyzed, a group with bcl-2（＋） and p53（-） had the best prognosis. This group was significantly associated with earlier Dukes＇ stages （P=0.1763）. In multivariate Cox regression analysis, lymph node involvement and p53 protein expression were two independent factors correlated with survival time. Conclusion： The expression ofbcl-2 and p53 represent biological characteristics of colorectal carcinomas. Assessment of both bcl-2 and p53 status may be valuable in predicting the prognosis of patients.