Identification of novel small molecules that inhibit protein-protein interactions between MAGE and KAP-1

Arch Biochem Biophys. 2011 Apr 15;508(2):217-21. doi: 10.1016/j.abb.2011.01.007. Epub 2011 Jan 28.

Abstract

The Class I MAGE proteins are normally expressed only in developing germ cells but are often aberrantly expressed in malignancies, particularly melanoma, making them good therapeutic targets. MAGE proteins promote tumor survival by binding to the RBCC region of KAP-1 and suppressing p53. Although, suppression of MAGE expression, by RNA interference, relieves p53 suppression and inhibits tumor growth, its therapeutic uses are limited by lack of methods for systemic delivery of small interfering RNA. To overcome this barrier, we sought to discover chemical compounds that inhibit binding between MAGE and KAP-1 proteins. Based on previously published effects of MAGE suppression, we developed a strategy for screening a small molecule library based on selective death of MAGE positive cells, activation of p53 and lack of caspase activity. We screened the Maybridge HitFinder library of compounds and eight compounds fulfilled these criteria. Seven of these compounds interfered with co-precipitation of MAGE and KAP-1, and three interfered with binding of MAGE and KAP-1 in a mammalian two hybrid assay. We now report identification of three potential compounds that interfere with MAGE/KAP-1 binding and can be developed as novel chemo-therapeutic agents for treatment of advanced melanoma and other cancers.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antigens, Neoplasm / metabolism*
  • Antineoplastic Agents / chemistry*
  • Antineoplastic Agents / pharmacology*
  • CHO Cells
  • Cell Line, Tumor
  • Cricetinae
  • Cricetulus
  • Drug Evaluation, Preclinical
  • High-Throughput Screening Assays
  • Humans
  • Protein Binding / drug effects
  • Repressor Proteins / chemistry
  • Repressor Proteins / metabolism*
  • Tripartite Motif-Containing Protein 28

Substances

  • Antigens, Neoplasm
  • Antineoplastic Agents
  • Repressor Proteins
  • TRIM28 protein, human
  • Tripartite Motif-Containing Protein 28