Alternative lengthening of telomeres renders cancer cells hypersensitive to ATR inhibitors

Science. 2015 Jan 16;347(6219):273-7. doi: 10.1126/science.1257216.

Abstract

Cancer cells rely on telomerase or the alternative lengthening of telomeres (ALT) pathway to overcome replicative mortality. ALT is mediated by recombination and is prevalent in a subset of human cancers, yet whether it can be exploited therapeutically remains unknown. Loss of the chromatin-remodeling protein ATRX associates with ALT in cancers. Here, we show that ATRX loss compromises cell-cycle regulation of the telomeric noncoding RNA TERRA and leads to persistent association of replication protein A (RPA) with telomeres after DNA replication, creating a recombinogenic nucleoprotein structure. Inhibition of the protein kinase ATR, a critical regulator of recombination recruited by RPA, disrupts ALT and triggers chromosome fragmentation and apoptosis in ALT cells. The cell death induced by ATR inhibitors is highly selective for cancer cells that rely on ALT, suggesting that such inhibitors may be useful for treatment of ALT-positive cancers.

Publication types

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

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Apoptosis
  • Ataxia Telangiectasia Mutated Proteins / antagonists & inhibitors
  • Ataxia Telangiectasia Mutated Proteins / metabolism
  • Cell Cycle
  • Cell Line, Tumor
  • DNA Helicases / genetics
  • DNA Helicases / metabolism
  • Gene Knockdown Techniques
  • Glioma / drug therapy
  • Glioma / genetics
  • HeLa Cells
  • Homologous Recombination
  • Humans
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Osteosarcoma / drug therapy
  • Osteosarcoma / genetics
  • Promyelocytic Leukemia Protein
  • Pyrazines / pharmacology*
  • RNA, Untranslated / genetics
  • RNA, Untranslated / metabolism
  • Replication Protein A / metabolism
  • Sulfones / pharmacology*
  • Telomerase / metabolism
  • Telomere / drug effects*
  • Telomere / genetics
  • Telomere / metabolism*
  • Telomere Homeostasis*
  • Telomeric Repeat Binding Protein 2 / metabolism
  • Transcription Factors / metabolism
  • Tumor Suppressor Proteins / metabolism
  • X-linked Nuclear Protein

Substances

  • 3-amino-6-(4-(methylsulfonyl)phenyl)-N-phenylpyrazine-2-carboxamide
  • Antineoplastic Agents
  • Nuclear Proteins
  • Promyelocytic Leukemia Protein
  • Pyrazines
  • RNA, Untranslated
  • RPA1 protein, human
  • Replication Protein A
  • Sulfones
  • TERF2 protein, human
  • Telomeric Repeat Binding Protein 2
  • Transcription Factors
  • Tumor Suppressor Proteins
  • PML protein, human
  • ATR protein, human
  • Ataxia Telangiectasia Mutated Proteins
  • Telomerase
  • DNA Helicases
  • ATRX protein, human
  • X-linked Nuclear Protein