Apoptosis and Proliferative Activity of Non-Hodgkin's Lymphoma: Correlation with Bcl-2 and P53 Protein Expression / 대한방사선종양학회지

ABSTRACT

PURPOSE: Tumor growth in a given neoplasm is the net result of cell proliferation and cell loss, and apoptosis is the most significant component of continuous cell loss in most tumors. In this study, we examined non-Hodgkin's lymphoma (NHL, n=67) immunohistochemically for the presence of Bcl-2 oncoprotein and P53 protein and compared apoptotic indices (AIs) and Ki-67 proliferative indices (percentages of Ki-67 positive cells). MATERIALS AND METHODS: 67 patients with NHL were evaluated 3 low-grade and 64 intermediate-grade. The phenotype was determined in 65 cases 47 (70%) were B cell type and 18 (27%) were T cell type. AIs and Ki-67 proliferative indices were determined immunohistochemically and the overexpression of P53 and Bcl-2 protein were also evalutated. RESULTS: The overexpressions of Bcl-2 protein and P53 protein were found in 40% (26/65) and 31% (20/ 65). The AI ranged from 0% to 15% (mean 2.16, median 1.2). Cellular Bcl-2, which counteracts apoptosis, was significantly ( p=0.005) associated with AIs. Ki-67 proliferative indices ranged from 1% to 91% (mean 55.4), and P53 was significantly ( p=0.000) associated with Ki-67 proliferative indices. A positive correlation between AIs and Ki-67 proliferative indices was revealed ( p=0.012) in Bcl-2 positive patients. CONCLUSION: In NHL, we observed a correlation between AIs and Bcl-2 expression, between Ki-67 proliferative indices and P53 expression, and between AIs and Ki-67 proliferative indices in Bcl-2 positive patients. Our results suggest that cell apoptosis may be inseparable from cell proliferation during tumor growth.