Expression of Bcl-2 and Bcl-2-Ig fusion transcripts in normal and neoplastic cells

J Clin Invest. 1987 Nov;80(5):1512-5. doi: 10.1172/JCI113235.


We examined the expression of the Bcl-2 gene at chromosome segment 18q21, that is translocated into the Ig heavy chain gene locus in t(14;18) bearing lymphomas. Bcl-2, while B cell associated, is expressed in a variety of hematopoietic lineages including T cells. Bcl-2 mRNA levels are high during pre-B cell development, the time at which the t(14;18) translocation occurs, but are down regulated with maturation. Like certain other oncogenes, Bcl-2 is quiescent in resting B cells but up-regulated with B cell activation. Mature B cell lymphomas with a t(14;18) have log-folds more mRNA than matched counterparts without the translocation. A sensitive S1 protection assay revealed that all transcripts in t(14;18) B cells were Bcl-2-Ig fusion mRNAs and originated from the translocated allele. Thus, there is a marked deregulation of Bcl-2 when it is introduced into the Ig locus in t(14;18) lymphomas.

MeSH terms

  • B-Lymphocytes / metabolism
  • Cell Differentiation
  • Chromosomes, Human, Pair 14*
  • Chromosomes, Human, Pair 18*
  • Gene Expression Regulation*
  • Humans
  • Lymphocyte Activation
  • Lymphocytes / metabolism*
  • Lymphoma / genetics*
  • Oncogenes*
  • RNA, Messenger / genetics
  • T-Lymphocytes / metabolism
  • Transcription, Genetic*
  • Translocation, Genetic
  • Tumor Cells, Cultured


  • RNA, Messenger