BCL-6 gene product, a 92- to 98-kD nuclear phosphoprotein, is highly expressed in germinal center B cells and their neoplastic counterparts

Blood. 1995 Jul 1;86(1):28-37.

Abstract

The BCL-6 gene is known to be located on chromosome 3q27, at the breakpoint of the 3q27-associated translocations that occur frequently in human non-Hodgkin's lymphomas (NHLs). To identify the BCL-6 protein, two antibodies that recognized distinct domains of this protein were raised in rabbits. Immunoprecipitation and immunoblotting of lysates of BCL-6-expressing cells using both antibodies showed a broad 92- to 98-kD band. Dephosphorylation of BCL-6 protein reduced the size of this band to 87 kD, suggesting that BCL-6 may be expressed in a phosphorylated form. Immunostaining with both antibodies showed that BCL-6 protein was localized in the nuclei of most of the germinal center B cells and a small number of marginal zone B cells. Furthermore, BCL-6 protein was expressed in follicular, Burkitt's, and diffuse large B-cell lymphomas. These results suggest that the BCL-6 protein, expressed in B cells of the germinal centers which are important in the maturation of immune responses, may play some physiological role(s) in the germinal center B cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / immunology
  • B-Lymphocyte Subsets / metabolism*
  • Base Sequence
  • Bone Neoplasms / genetics
  • Bone Neoplasms / metabolism
  • Bone Neoplasms / pathology
  • Burkitt Lymphoma / genetics
  • Burkitt Lymphoma / metabolism
  • Burkitt Lymphoma / pathology
  • Cell Nucleus / metabolism
  • DNA-Binding Proteins / biosynthesis*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / immunology
  • Gene Expression Regulation, Leukemic
  • Gene Expression Regulation, Neoplastic*
  • Leukemia / genetics
  • Leukemia / metabolism
  • Leukemia-Lymphoma, Adult T-Cell / genetics
  • Leukemia-Lymphoma, Adult T-Cell / metabolism
  • Leukemia-Lymphoma, Adult T-Cell / pathology
  • Lymphoma, B-Cell / genetics
  • Lymphoma, B-Cell / metabolism
  • Lymphoma, Large B-Cell, Diffuse / genetics
  • Lymphoma, Large B-Cell, Diffuse / metabolism
  • Lymphoma, Non-Hodgkin / genetics
  • Lymphoma, Non-Hodgkin / metabolism*
  • Mice
  • Mice, SCID
  • Molecular Sequence Data
  • Neoplasm Proteins / biosynthesis*
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / immunology
  • Osteosarcoma / genetics
  • Osteosarcoma / metabolism
  • Osteosarcoma / pathology
  • Palatine Tonsil / cytology*
  • Phosphorylation
  • Protein Processing, Post-Translational
  • Proto-Oncogene Proteins / biosynthesis*
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / immunology
  • Proto-Oncogene Proteins c-bcl-6
  • Rabbits
  • Transcription Factors / biosynthesis*
  • Transcription Factors / genetics
  • Transcription Factors / immunology
  • Tumor Cells, Cultured
  • Tunicamycin / pharmacology

Substances

  • Antibodies, Monoclonal
  • DNA-Binding Proteins
  • Neoplasm Proteins
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-bcl-6
  • Transcription Factors
  • Tunicamycin