1995 Fiscal Year Final Research Report Summary

Molecular biology of 3q27 translocation in lymphoid malignancies

Research Project

Project/Area Number	06671110
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Hematology
Research Institution	Dokkyo University School of Medicine
Principal Investigator	NAKAMURA Yuichi Dokkyo University School of Medicine, Department of Medicine, Lecturer, 医学部, 講師 (20227896)
Project Period (FY)	1994 – 1995
Keywords	Malignant lymphoma / Chromosomal translocation / BCL6 gene
Research Abstract	First, we studied the structural alterations within the 5' part of the BCL6 gene on the band 3q27, where is frequently affected by chromosomal translocations in B cell non-Hodgkin's lymphoma (B-NHL) patients. We found that five out of 11 patients with BCL6 abnormality had two independent DNA rearrangements on both alleles, presenting multiple rearranged bands on Southern blotting. Furthermore, in one of them, it was revealed that an internal DNA deletion of 1.5kb area was generated within the BCL6 locus on untranslocated chromosome 3. Our results suggest that the occurrence of biallelic rearrangements and submicroscopic local recombinations would be unique features with BCL6 abnormality in B-NHL.Next, we analyzed aberrant expressions of the BCL6 mRNA recognized in two cell lines harboring 3q27 translocations. Analysis of cDNA from these cells revealed that the 5' non-coding region of the BCL6 mRNA was substituted by transcripts from immunoglobulin genes including intronic sequences, forming unique chimeric transcripts.