title: A synthetic lethal siRNA screen identifying genes mediating sensitivity to a PARP inhibitor.
abstract: Inhibitors of poly (ADP-ribose)-polymerase-1 (PARP) are highly lethal to cells with deficiencies in BRCA1, BRCA2 or other components of the homologous recombination pathway. This has led to PARP inhibitors entering clinical trials as a potential therapy for cancer in carriers of BRCA1 and BRCA2 mutations. To discover new determinants of sensitivity to these drugs, we performed a PARP-inhibitor synthetic lethal short interfering RNA (siRNA) screen. We identified a number of kinases whose silencing strongly sensitised to PARP inhibitor, including cyclin-dependent kinase 5 (CDK5), MAPK12, PLK3, PNKP, STK22c and STK36. How CDK5 silencing mediates sensitivity was investigated. Previously, CDK5 has been suggested to be active only in a neuronal context, but here we show that CDK5 is required in non-neuronal cells for the DNA-damage response and, in particular, intra-S and G(2)/M cell-cycle checkpoints. These results highlight the potential of synthetic lethal siRNA screens with chemical inhibitors to define new determinants of sensitivity and potential therapeutic targets.
authors.affiliation: The Breakthrough Breast Cancer Research Centre, The Institute of Cancer Research, London, UK.
authors.forename: Nicholas C
authors.initials: NC
authors.lastname: Turner
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Lord
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Iorns
authors.forename: Rachel
authors.initials: R
authors.lastname: Brough
authors.forename: Sally
authors.initials: S
authors.lastname: Swift
authors.forename: Richard
authors.initials: R
authors.lastname: Elliott
authors.forename: Sydonia
authors.initials: S
authors.lastname: Rayter
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Tutt
authors.forename: Alan
authors.initials: A
authors.lastname: Ashworth
mesh_terms: D015153:Blotting, Western; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D051360:Cyclin-Dependent Kinase 5 / Q000235:genetics / Q000378:metabolism; D004249:DNA Damage; D004260:DNA Repair; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D048291:Mitogen-Activated Protein Kinase 12 / Q000235:genetics / Q000378:metabolism; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics*; D014162:Transfection; D025521:Tumor Suppressor Proteins; D000097868:Polo-like Kinases
chemical_list: D051360:Cyclin-Dependent Kinase 5; D006861:Hydrogen Peroxide; D048291:Mitogen-Activated Protein Kinase 12; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D011065:Poly(ADP-ribose) Polymerases; D017346:Protein Serine-Threonine Kinases; D034741:RNA, Small Interfering; D025521:Tumor Suppressor Proteins; C486256:PLK3 protein, human; D000097868:Polo-like Kinases; C496588:STK36 protein, human