BCL-2 EXPRESSION CORRELATES WITH LOWER PROLIFERATIVE ACTIVITY IN THE INTERMEDIATE-GRADE AND HIGH-GRADE NON-HODGKINS-LYMPHOMAS - AN EASTERN CCOOPERATIVE ONCOLOGY GROUP AND SOUTHWEST-ONCOLOGY-GROUP COOPERATIVE LABORATORY STUDY

An inverse relationship between BCL-2 expression and cell cycle transi tion has been suggested by recent studies in murine models. To investi gate the clinical relevance of these laboratory studies, a group of 11 6 paraffin-embedded non-Hodgkin's lymphoma (NHL) biopsy specimens (Wor king Formulation Groups D-H, and J) from a cooperative group study of cellular DNA content were analyzed for the 14;18 translocation using p olymerase chain reaction (PCR)-based methods and, if sufficient tissue remained, for BCL-2 and BAX expression by immunohistochemistry. The r esults of these studies were then compared with the results of the pre viously performed flow cytometric analysis of ploidy and proliferative activity (S-phase-fraction). BCL-2 expression was inversely associate d with proliferative activity (P = .001; n = 41), but there was no ass ociation between staining for Fax and %S-phase. Ploidy was not associa ted with either BCL-2 or BAX expression. The t(14;18) was detected in 21 of the 54 cases in which PCR-amplifiable DNA was recovered; 20 of t hese occurred at the major breakpoint region and 1 at the minor breakp oint region. High levels of BCL-2 or BAX expression occurred independe ntly of t(14;18). There was no association between t(14;18) and either ploidy or proliferative activity. The inverse relationship between BC L-2 expression and proliferative activity in the intermediate- and hig h-grade NHLs is consistent with recent studies suggesting that Bcl-2 b oth retards entry into the cell cycle and inhibits apoptosis. (C) 1998 by The American Society of Hematology.