Bax mutations are an infrequent event in indolent lymphomas and in mantle cell lymphoma

Background and Objectives. The Bar gene is one of the most important genes involved in apoptosis regulation. Recently, it has been proposed that inact ivating mutations of this death agonist may contribute to the pathogenesis of human tumors. This study was aimed at defining the status of the Bar gen e in indolent lymphomas. Design and Methods. Fifty paraffin-embedded biopsies from patients with ind olent lymphomas (10 small lymphocytic lymphomas, 5 immunocytomas, 20 follic ular lymphomas and 15 marginal zone lymphomas) and 10 mantle cell lymphomas (MCL) were studied. All six exons of the Bar gene, together with their fla nking sequences, underwent mutational analysis by PCR-SSCP followed by dire ct sequencing of positive cases. Moreover, Bar protein expression was inves tigated in all samples by immunohistochemical analysis. Results. All analyzed cases showed wild type Bar gene alleles and variable levels of Bar protein expression. Interpretation and Conclusions. This study indicates that deregulation of a poptotic control in indolent lymphomas and MCL is not caused by bar mutatio ns and that other molecular mechanisms must, therefore, be involved. (C)200 0, Ferrata Storti Foundation.