Chemical Genetic Screens Identify Kinase Inhibitor Combinations that Target Anti-Apoptotic Proteins for Cancer Therapy

ACS Chem Biol. 2018 May 18;13(5):1148-1152. doi: 10.1021/acschembio.8b00077. Epub 2018 Apr 5.

Abstract

The study presented here provides a framework for the discovery of unique inhibitor combinations that target the apoptosis network for cancer therapy. A pair of doxycycline (Dox)-inducible cell lines that specifically report on the ability of an inhibitor to induce apoptosis by targeting either the Mcl-1 arm or the Bcl-2/Bcl-xL/Bcl-w arm were used. Cell-based assays were optimized for high throughput screening (HTS) with caspase 3/7 as a read out. HTS with a 355-member kinase inhibitor library and the panel of Dox-inducible cell lines revealed that cyclin dependent kinase (CDK) inhibitors induced apoptosis by targeting the Mcl-1 arm, whereas PI3K inhibitors induced apoptosis by targeting the Bcl-2/Bcl-xL/Bcl-w arm. Validation studies identified unique combinations that synergistically inhibited growth and induced apoptosis in a panel of cancer cell lines. Since these inhibitors have been or are currently in clinical trials as single agents, the combinations can be rapidly translated to the clinics.

Publication types

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

MeSH terms

  • Apoptosis Regulatory Proteins / drug effects*
  • Apoptosis Regulatory Proteins / metabolism
  • Cell Line, Tumor
  • Doxycycline / pharmacology
  • Drug Therapy, Combination
  • High-Throughput Screening Assays
  • Humans
  • Neoplasms / drug therapy*
  • Protein Kinase Inhibitors / administration & dosage
  • Protein Kinase Inhibitors / pharmacology*
  • Protein Kinase Inhibitors / therapeutic use
  • Proto-Oncogene Proteins c-bcl-2 / drug effects
  • Proto-Oncogene Proteins c-bcl-2 / metabolism

Substances

  • Apoptosis Regulatory Proteins
  • Protein Kinase Inhibitors
  • Proto-Oncogene Proteins c-bcl-2
  • Doxycycline