Discovery of Dual Inhibitors of MDM2 and XIAP for Cancer Treatment

Cancer Cell. 2016 Oct 10;30(4):623-636. doi: 10.1016/j.ccell.2016.08.015. Epub 2016 Sep 22.

Abstract

MDM2 and XIAP are mutually regulated. Binding of MDM2 RING protein to the IRES region on XIAP mRNA results in MDM2 protein stabilization and enhanced XIAP translation. In this study, we developed a protein-RNA fluorescence polarization (FP) assay for high-throughput screening (HTS) of chemical libraries. Our FP-HTS identified eight inhibitors that blocked the MDM2 protein-XIAP RNA interaction, leading to MDM2 degradation. The compound-induced MDM2 downregulation resulted not only in inhibition of XIAP expression, but also in activation of p53, which contributed to cancer cell apoptosis in vitro and inhibition of cancer cell proliferation in vivo. Importantly, one of the MDM2/XIAP inhibitors, MX69, showed minimal inhibitory effect on normal human hematopoiesis in vitro and was very well tolerated in animal models.

Publication types

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

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Female
  • Humans
  • Mice
  • Mice, SCID
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / drug therapy*
  • Proto-Oncogene Proteins c-mdm2 / antagonists & inhibitors*
  • X-Linked Inhibitor of Apoptosis Protein / antagonists & inhibitors*
  • Xenograft Model Antitumor Assays

Substances

  • X-Linked Inhibitor of Apoptosis Protein
  • XIAP protein, human
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2