Analysis of Nuclear Factor Kappa B in Mantle Cell Lymphoma.

Gene expression profiles revealed that proliferation associated genes are important prognostic factors in the clinical outcome in mantle cell lymphoma (MCL). Beside this well accepted markers also analysis of apoptotic proteins are now under investigation. We investigated immunohistochemically the expression of the apoptotic marker NF-kB in relation to the clinical course in 89 patients enrolled in two multicenter prospective trials. Biopsies were recut and stained with mandatory antibodies (CD20, CD5, CD3, CD23, cyclin D1) and NF-kB. The NF-kB expression was analyzed in three groups: negative, cytoplasmatic positive and nuclear positive (more than 1/HPF). The expression was compared with the overall survival data analyzed according to Kaplan and Meier. In 13 cases a negative NF-kB staining was detected. Fifty-seven cases were positive only in the cytoplasma and in 17 cases more than 1 cell per high power field showed nuclear activity. Patients with mantle cell lymphoma that had negative and cytoplasmatic positive expression had a median overall survival time of 35.7 months compared to 22.4 months for patients with a nuclear NF-kB expression. The Kaplan-Meier analysis showed a significant difference in the overall survival time (p=0.0121). The immunohistochemical detection of NF-kB in mantle cell lymphoma is possible and a tool to identify patients with a poor prognosis.