Plasmacytomagenesis in Eμ-v-abl transgenic mice is accelerated when apoptosis is restrained

Blood. 2014 Aug 14;124(7):1099-109. doi: 10.1182/blood-2014-04-570770. Epub 2014 Jul 1.

Abstract

Mice susceptible to plasma cell tumors provide a useful model for human multiple myeloma. We previously showed that mice expressing an Eµ-v-abl oncogene solely develop plasmacytomas. Here we show that loss of the proapoptotic BH3-only protein Bim or, to a lesser extent, overexpression of antiapoptotic Bcl-2 or Mcl-1, significantly accelerated the development of plasmacytomas and increased their incidence. Disease was preceded by an increased abundance of plasma cells, presumably reflecting their enhanced survival capacity in vivo. Plasmacytomas of each genotype expressed high levels of v-abl and frequently harbored a rearranged c-myc gene, probably as a result of chromosome translocation. As in human multiple myelomas, elevated expression of cyclin D genes was common, and p53 deregulation was rare. Our results for plasmacytomas highlight the significance of antiapoptotic changes in multiple myeloma, which include elevated expression of Mcl-1 and, less frequently, Bcl-2, and suggest that closer attention to defects in Bim expression is warranted.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / genetics*
  • Apoptosis Regulatory Proteins / genetics
  • Apoptosis Regulatory Proteins / metabolism
  • Bcl-2-Like Protein 11
  • Blotting, Western
  • Cells, Cultured
  • Cyclin D1 / genetics
  • Cyclin D1 / metabolism
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Kaplan-Meier Estimate
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Multiple Myeloma / genetics
  • Mutation
  • Myeloid Cell Leukemia Sequence 1 Protein / genetics
  • Myeloid Cell Leukemia Sequence 1 Protein / metabolism
  • Plasmacytoma / genetics*
  • Plasmacytoma / metabolism
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins c-abl / genetics*
  • Proto-Oncogene Proteins c-abl / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / genetics
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • Apoptosis Regulatory Proteins
  • BCL2L11 protein, human
  • Bcl-2-Like Protein 11
  • Bcl2l11 protein, mouse
  • Mcl1 protein, mouse
  • Membrane Proteins
  • Myeloid Cell Leukemia Sequence 1 Protein
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • Proto-Oncogene Proteins c-myc
  • Tumor Suppressor Protein p53
  • Cyclin D1
  • Proto-Oncogene Proteins c-abl