ANALYSIS OF THE BCL-6 GENE CONFIGURATION IN DIFFUSE B-CELL NON-HODGKINS-LYMPHOMAS AND HODGKINS-DISEASE

BCL-6 is a novel proto-oncogene that codes for a zinc-finger protein s haring homologies with many transcription factors. It has recently bee n shown that BCL-6 is involved in chromosome band 3q27 aberrations in non-Hodgkin's lymphomas (NHLs) and BCL-6 rearrangements have been dete cted in 34-45 per cent of diffuse large cell lymphomas with B immunoph enotype. We have studied the BCL-6 gene configuration by Southern blot analysis in 60 cases of B-cell NHL and in 17 cases of Hodgkin's disea se (HD). BCL-6 was rearranged in 15/46 (32.6 per cent) diffuse B-large cell lymphomas, mainly with centroblastic morphology, and in 2/11 (18 .2 per cent) follicular (centroblastic-centrocytic) lymphomas. Convers ely, all cases of HD, including four cases of lymphocyte predominant, nodular type (nodular paragranuloma), had a germline configuration. Th ese findings confirm that BCL-6 is rearranged in a significant percent age of diffuse B-large cell lymphomas, suggesting that this proto-onco gene might have a pathogenetic role in this subset of NHLs, but our pr eliminary analysis suggests that BCL-6 lesions are not involved in the pathogenesis of HD. However, further investigations using more sensit ive techniques are required to confirm these findings.