An shRNA barcode screen provides insight into cancer cell vulnerability to MDM2 inhibitors

Nat Chem Biol. 2006 Apr;2(4):202-6. doi: 10.1038/nchembio774. Epub 2006 Feb 13.


The identification of the cellular targets of small molecules with anticancer activity is crucial to their further development as drug candidates. Here, we present the application of a large-scale RNA interference-based short hairpin RNA (shRNA) barcode screen to gain insight in the mechanism of action of nutlin-3 (1). Nutlin-3 is a small-molecule inhibitor of MDM2, which can activate the p53 pathway. Nutlin-3 shows strong antitumor effects in mice, with surprisingly few side effects on normal tissues. Aside from p53, we here identify 53BP1 as a critical mediator of nutlin-3-induced cytotoxicity. 53BP1 is part of a signaling network induced by DNA damage that is frequently activated in cancer but not in healthy tissues. Our results suggest that nutlin-3's tumor specificity may result from its ability to turn a cancer cell-specific property (activated DNA damage signaling) into a weakness that can be exploited therapeutically.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology
  • Blotting, Western
  • Cell Line, Tumor
  • Cells, Cultured
  • DNA Damage
  • Electronic Data Processing
  • Fibroblasts / metabolism
  • Gene Expression Regulation, Neoplastic*
  • Genes, p53
  • Genetic Techniques*
  • Humans
  • Imidazoles / chemistry
  • Intracellular Signaling Peptides and Proteins / chemistry
  • Mice
  • Microscopy, Fluorescence
  • Models, Chemical
  • Neoplasms / drug therapy*
  • Nuclear Proteins
  • Nucleic Acid Hybridization
  • Oligonucleotide Array Sequence Analysis
  • Phosphoproteins / chemistry
  • Piperazines / chemistry
  • Plasmids / metabolism
  • Proto-Oncogene Proteins c-mdm2 / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-mdm2 / metabolism*
  • RNA Interference
  • RNA, Small Interfering / chemistry*
  • Signal Transduction
  • Tumor Suppressor Protein p53 / metabolism
  • Tumor Suppressor p53-Binding Protein 1


  • Antineoplastic Agents
  • Imidazoles
  • Intracellular Signaling Peptides and Proteins
  • Nuclear Proteins
  • Phosphoproteins
  • Piperazines
  • RNA, Small Interfering
  • TP53BP1 protein, human
  • Tumor Suppressor Protein p53
  • Tumor Suppressor p53-Binding Protein 1
  • nutlin 3
  • Proto-Oncogene Proteins c-mdm2

Associated data

  • PubChem-Substance/8139831
  • PubChem-Substance/8139832