Frequency of bcl-2 Gene Rearrangement in B-Cell Non Hodgkin’s Lymphoma

Abstract

<br/><b>Objective</b>: The objective of the study was to determine the frequency of bcl-2 gene rearrangement in B-cellNon-Hodgkin’s lymphoma (NHL) and identify different breakpoints of bcl-2 gene. <br/><b>Methods</b>: Thirty cases of Bcelllymphoma (including 8 cases of follicular lymphoma, 19 cases of diffuse large B-cell lymphoma and 3 casesof T-cell rich B-cell lymphoma) were included in the study. Good quality of DNA was extracted in 4 cases fromformalin fixed paraffin embedded tissue and in 26 cases from fine needle aspirate. The polymerase chain reactionwas done for major break point region (mbr), minor cluster region (mcr) and intermediate cluster region (icr) ofbcl-2 gene. <br/><b>Results</b>: The bcl-2 gene rearrangement was identified in 23.3% of B-cell lymphoma, 50% of follicularlymphoma, 15% of diffuse large B-cell lymphoma and no bcl-2 rearrangement was identified in any of the T-cellrich B-cell lymphomas. Further analysis showed, icr breakpoint in 16.7% of B-cell lymphoma, 37.5% of follicularlymphoma and 10.5% of diffuse large B-cell lymphoma. Involvement of mbr breakpoint was found in 6.7% ofB-cell lymphoma, 12.5% of follicular lymphoma, 5.3% of diffuse large B-cell lymphoma. Involvement of mcrbreakpoint was not seen in any of the case. <br/><b>Conclusion</b>: The bcl-2 gene rearrangement is quite frequent infollicular lymphoma, followed by diffuse large B-cell lymphoma. The commonest breakpoint in present series isicr followed by mbr. This indicates that primers for bcl-2 gene must include icr primer, whenever bcl-2 gene isbeing evaluated for B-cell NHL in this part of the world and this might reduce the variability of frequency ofbcl-2 gene rearrangement within and between different regions.