A comparative study between NHL associated either with BCL2 or BCL6 rearrangement showed that advanced disease and bone marrow involvement were more frequent in BCL2(+) NHL.
One patient with follicular small cleaved cell NHL that evolved to a small noncleaved cell NHL had coexisting bcl-2 and c-myc rearrangement in the aspiration specimen of the high-grade NHL, suggesting sequential bcl-2 and c-myc activation during the tumor's progression.
The NHL was considered a histological conversion from follicular lymphoma because lymphoma cells carried t(14;18) (q32;q21) and were strongly positive for BCL2 protein.
Ongoing clinical trials are exploring the role of Bcl-2 downregulation with oblimersen (Bcl-2 antisense) in patients with non-Hodgkin's lymphoma, chronic lymphocytic leukemia and multiple myeloma.
Fourteen patients with FSCCL and 1 patient with DSCCL had a phenotype of follicular center cells (FCC) (CALLA+, SIgD-, Leu-1-, Leu-8- and negative ALPase), and 11 patients with FSCCL had bcl-2 gene rearrangements.
DNA was extracted from archival CPs of B-cell NHL cases with previous fluorescence in situ hybridization (FISH) assays for MYC rearrangement and/or IGH/BCL-2 translocation.
Translocations involving 3q27 that affect the BCL6 gene are common and specific chromosomal abnormalities in B-cell precursor non-Hodgkin lymphoma (mainly diffuse large-cell and follicular lymphoma), but they have not been reported in Burkitt lymphoma.
Small deletions occur in highly conserved regions of the LAZ3/BCL6 major translocation cluster in one case of non-Hodgkin's lymphoma without 3q27 translocation.
These modifications induced by rituximab were in large part responsible for the down-regulation of the anti-apoptotic gene products Bcl-2/Bcl-xL and chemosensitization of the drug-resistant B-NHL cell lines to various drug-induced apoptosis.
This study suggests that BCL6 rearrangement is primarily associated with large cell lymphoma, and that BCL2(-)BCL6(+) NHL could potentially be curable with modern combination chemotherapy.
Using fluorescence in situ hybridization and molecular analyses, we report here on the rearrangement of the RhoH/TTF gene, at band 4p13, in four cases of NHL with t(3;4)(q27;p13) translocation and its fusion to the LAZ3/BCL6 gene at band 3q27, in three of these cases.
Twenty cases of Japanese non-Hodgkin's lymphoma with B cell markers were studied with respect to their immunoglobulin heavy (IgH) chain gene loci on chromosome 14 and BCL2 loci on chromosome 18.
This study was planned with the aim to investigate the association between bcl-2 gene rearrangements and apoptotic changes during chemotherapy in patients with non-Hodgkin's lymphoma.
The gene was identified by fusion to the BCL6/LAZ3 oncogene in an initially described t(3;4)(q27;p11) translocation in a non-Hodgkin's lymphoma cell line.
Fifty-one cases of intestinal non-Hodgkin's lymphoma (NHL) (10 small B-cell mucosa-associated lymphoid tissue [MALT] NHLs, 12 large B-cell MALT NHLs, 18 large B-cell NHLs, 2 small T-cell NHLs, 7 large T-cell NHLs, and 2 mantle cell NHLs) were studied for the immunohistochemical expression of MIB-1 and the TUNEL assay as well as the expression of bcl-2 and p53, both of which are regulatory gene products involved in apoptosis.
High bcl-2 expression was more frequent in B-cell NHL (109 of 214, 51%) than in T-cell NHL (6 of 35, 17%) (P = .0004), and was heterogeneously distributed among the different histological subtypes.