Hypoxia-inducible factor (HIF)-1α suppression in myeloma cells blocks tumoral growth in vivo inhibiting angiogenesis and bone destruction

Leukemia. 2013 Aug;27(8):1697-706. doi: 10.1038/leu.2013.24. Epub 2013 Jan 24.

Abstract

Hypoxia-inducible transcription factor-1 (HIF-1α) is overexpressed in multiple myeloma (MM) cells within the hypoxic microenvironment. Herein, we explored the effect of persistent HIF-1α inhibition by a lentivirus short hairpin RNA pool on MM cell growth either in vitro or in vivo and on the transcriptional and pro-angiogenic profiles of MM cells. HIF-1α suppression did not have a significant impact on MM cell proliferation and survival in vitro although, increased the antiproliferative effect of lenalidomide. On the other hand, we found that HIF-1α inhibition in MM cells downregulates the pro-angiogenic genes VEGF, IL8, IL10, CCL2, CCL5 and MMP9. Pro-osteoclastogenic cytokines were also inhibited, such as IL-7 and CCL3/MIP-1α. The effect of HIF-1α inhibition was assessed in vivo in nonobese diabetic/severe combined immunodeficiency mice both in a subcutaneous and an intratibial MM model. HIF-1α inhibition caused a dramatic reduction in the weight and volume of the tumor burden in both mouse models. Moreover, a significant reduction of the number of vessels and vascular endothelial growth factors (VEGFs) immunostaining was observed. Finally, in the intratibial experiments, HIF-1α inhibition significantly blocked bone destruction. Overall, our data indicate that HIF-1α suppression in MM cells significantly blocks MM-induced angiogenesis and reduces MM tumor burden and bone destruction in vivo, supporting HIF-1α as a potential therapeutic target in MM.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Proliferation
  • Cell Survival / genetics
  • Disease Models, Animal
  • Drug Resistance, Neoplasm / genetics
  • Gene Expression Profiling
  • Gene Knockdown Techniques
  • Gene Silencing
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics*
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Mice
  • Multiple Myeloma / genetics*
  • Multiple Myeloma / pathology*
  • Neovascularization, Pathologic / genetics*
  • Osteolysis / genetics*
  • Osteolysis / pathology*
  • Tumor Burden / genetics

Substances

  • Hypoxia-Inducible Factor 1, alpha Subunit