Apoptosis Regulating Proteins bax and p53 in Mantle Cell Lymphoma.

In malignant tumors beside cell proliferation also cell death plays role for cell survival. Apoptosis regulating genes can be divided into two groups: death antagonists and death agonists such as bax. The ratio of death agonists and antagonists determines if a cell goes into apoptosis. We investigated in a large collective the immunohistochemical expression of the apoptotic marker p53 and bax in relation to the clinical course. Biopsies were stained immunohistochemically with monoclonal antibodies against bax and p53 and the expression was subdivided in three groups: negative, weak positive and strong positive. The expression profiles were analyzed with the overall survival data according to Kaplan and Meier. Patients with mantle cell lymphoma that had negative p53 expression had a median overall survival time of 38.1 months compared to 22.3 months for patients with a weak and 11.3 months for a strong p53 expression (0<0.0001). The bax expression was in the majority of cases positive. Only one case showed a negative staining. Patients with weak and strong bax expression showed no differences in clinical outcome (median overall survival time: 23 vs 33 months, p=0.6051). The immunohistochemical detection of p53 in mantle cell lymphoma is a good predictor for the clinical outcome.