Prognostic significance of Bcl-2 and p53 expression in gastric cancer

Abstract

Background and aims: Apoptosis regulates cell death and influences cell proliferation and therefore may play an important role in development or growth of various malignant tumors. The Bcl-2 and p53 are closely linked in the regulation of apoptosis. We investigated the prognostic significance of Bcl-2 and p53 expression in patients with gastric cancer. Patients and methods: Immunohistochemistry was used to study Bcl-2 and p53 expression in 308 consecutive patients with gastric cancer. Results: Bcl-2 expression was positive in 39 patients (12.7%) and showed a significant negative correlation with depth of invasion and lymph node metastasis. p53 expression was observed in 105 patients (34.1%) and was significantly associated with depth of invasion, lymph node metastasis, distant metastasis, and intestinal type. Patients with Bcl-2+ tumors showed a trend to better 5-year survival rate (81%) than those with Bcl-2- negative tumors (71%). The 5-year survival rate in p53 positive cases (60%) was significantly lower than that in p53-negative cases (78%). In addition, p53 expression showed a significantly poorer prognosis in both diffuse and intestinal types. In multivariate analysis restricted to patients with R0 resection p53 expression was an independent prognostic factor (relative risk: 2.063). In combined assessment of p53 and Bcl-2 expression the group with p53+/Bcl-2- tumors showed significantly worse 5-year survival (57%) than the other groups, while best survival was seen in the group with p53+/Bcl-2+ tumors (100%). Conclusion: p53 expression is an unfavorable prognostic factor in gastric cancer. Bcl-2 expression may have possible prognostic value when combined with p53 expression.