We use cookies to improve your experience. By continuing to browse this site, you accept our cookie policy.×
Skip main navigation
Aging Health
Bioelectronics in Medicine
Biomarkers in Medicine
Breast Cancer Management
CNS Oncology
Colorectal Cancer
Concussion
Epigenomics
Future Cardiology
Future Medicine AI
Future Microbiology
Future Neurology
Future Oncology
Future Rare Diseases
Future Virology
Hepatic Oncology
HIV Therapy
Immunotherapy
International Journal of Endocrine Oncology
International Journal of Hematologic Oncology
Journal of 3D Printing in Medicine
Lung Cancer Management
Melanoma Management
Nanomedicine
Neurodegenerative Disease Management
Pain Management
Pediatric Health
Personalized Medicine
Pharmacogenomics
Regenerative Medicine

Differing clinical impact of BRCA1 and BRCA2 mutations in serous ovarian cancer

    Guoyan Liu

    Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

    Department of Gynecology & Obstetrics, Tianjin Medical University General Hospital, Tianjin, China

    ,
    Da Yang

    Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

    ,
    Yan Sun

    Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

    Department of Pathology, Tianjin Medical University Cancer Institute & Hospital, Tianjin, China

    ,
    Ilya Shmulevich

    Institute for Systems Biology, Seattle, WA, USA

    ,
    Fengxia Xue

    Department of Gynecology & Obstetrics, Tianjin Medical University General Hospital, Tianjin, China

    ,
    Anil K Sood

    Department of Cancer Biology & Center for RNAi & Non-Coding RNA, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

    Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

    &
    Wei Zhang

    * Author for correspondence

    Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.

    Published Online:https://doi.org/10.2217/pgs.12.137

    A key function of BRCA1 and BRCA2 is the participation in dsDNAbreak repair via homologous recombination. BRCA1 and BRCA2 mutations, which occur in most hereditary ovarian cancers (OCs) and approximately 10% of all OC cases, are associated with defects in homologous recombination and genomic instability, a phenotype termed ‘BRCAness’. The clinical effects of BRCA1 and BRCA2 mutations have commonly been analyzed together; however, it is becoming increasingly apparent that these mutations do not have the same effects in OC. Recently, three major reports highlighted the unequal clinical characteristics of OCs with BRCA1 and BRCA2 mutations. All studies demonstrated that BRCA2-mutated patients are associated with better survival and therapeutic response than BRCA1-mutated and wild-type patients with serous OC. The differing prognostic effects of the BRCA2 and BRCA1 mutations is likely due to differing roles of BRCA1 and BRCA2 in homologous recombination repair and a stronger association between the BRCA2 mutation and a hypermutator phenotype. These new findings have potentially important implications for clinical management of patients with serous OC.

    Papers of special note have been highlighted as: ▪ of interest ▪▪ of considerable interest

    References

    • Pennington KP, Swisher EM. Hereditary ovarian cancer: beyond the usual suspects. Gynecol. Oncol.124(2),347–353 (2012).
    • King MC, Marks JH, Mandell JB. Breast and ovarian cancer risks due to inherited mutations in BRCA1 and BRCA2. Science302(5645),643–646 (2003).
    • Chen S, Parmigiani G. Meta-analysis of BRCA1 and BRCA2 penetrance. J. Clin. Oncol.25(11),1329–1333 (2007).
    • Sakai W, Swisher EM, Karlan BY et al. Secondary mutations as a mechanism of cisplatin resistance in BRCA2-mutated cancers. Nature451(7182),1116–1120 (2008).
    • Swisher EM, Sakai W, Karlan BY, Wurz K, Urban N, Taniguchi T. Secondary BRCA1 mutations in BRCA1-mutated ovarian carcinomas with platinum resistance. Cancer Res.68(8),2581–2586 (2008).
    • Yang D, Khan S, Sun Y et al. Association of BRCA1 and BRCA2 mutations with survival, chemotherapy sensitivity, and gene mutator phenotype in patients with ovarian cancer. JAMA306(14),1557–1565 (2011).▪ A comprehensive analysis of The Cancer Genome Atlas data on different effect of BRCA1 and BRCA2 mutations on drug response and hypermutator phenotype in ovarian cancer.
    • Hyman DM, Zhou Q, Iasonos A et al. Improved survival for BRCA2-associated serous ovarian cancer compared with both BRCA-negative and BRCA1-associated serous ovarian cancer. Cancer118(15),3703–3709 (2011).▪ Another important report of improved survival of BRCA2-mutated ovarian cancer patients.
    • Bolton Kl, Chenevix-Trench G, Goh C et al. Association between BRCA1 and BRCA2 mutations and survival in women with invasive epithelial ovarian cancer. JAMA307(4),382–390 (2012).▪▪ Large multicenter study on differing effect of BRCA1 and BRCA2 mutations on ovarian cancer survival.
    • Liu J, Cristea MC, Frankel P et al. Clinical characteristics and outcomes of BRCA-associated ovarian cancer: genotype and survival. Cancer Genet.205(1–2),34–41 (2012).
    • 10  Reitsma W, de Bock GH, Oosterwijk JC, Ten Hoor KA, Hollema H, Mourits MJ. Clinicopathologic characteristics and survival in BRCA1- and BRCA2-related adnexal cancer: are they different? Int. J. Gynecol. Cancer22(4),579–585 (2012).
    • 11  Whittemore AS, Gong G, Itnyre J. Prevalence and contribution of BRCA1 mutations in breast cancer and ovarian cancer: results from three U.S. population-based case–control studies of ovarian cancer. Am. J. Hum. Genet.60(3),496–504 (1997).
    • 12  Risch HA, McLaughlin JR, Cole DE et al. Prevalence and penetrance of germline BRCA1 and BRCA2 mutations in a population series of 649 women with ovarian cancer. Am. J. Hum. Genet.68(3),700–710 (2001).
    • 13  Rubin SC, Blackwood MA, Bandera C et al.BRCA1, BRCA2, and hereditary nonpolyposis colorectal cancer gene mutations in an unselected ovarian cancer population: relationship to family history and implications for genetic testing. Am. J. Obstet. Gynecol.178(4),670–677 (1998).
    • 14  Pal T, Permuth-Wey J, Betts JA et al.BRCA1 and BRCA2 mutations account for a large proportion of ovarian carcinoma cases. Cancer104(12),2807–2816 (2005).
    • 15  Press JZ, De Luca A, Boyd N et al. Ovarian carcinomas with genetic and epigenetic BRCA1 loss have distinct molecular abnormalities. BMC Cancer8,17 (2008).
    • 16  Levine DA, Argenta PA, Yee CJ et al. Fallopian tube and primary peritoneal carcinomas associated with BRCA mutations. J. Clin. Oncol.21(22),4222–4227 (2003).
    • 17  Crum CP, Drapkin R, Miron A et al. The distal fallopian tube: a new model for pelvic serous carcinogenesis. Curr. Opin Obstet. Gynecol.19(1),3–9 (2007).
    • 18  Norquist BM, Garcia RL, Allison KH et al. The molecular pathogenesis of hereditary ovarian carcinoma: alterations in the tubal epithelium of women with BRCA1 and BRCA2 mutations. Cancer116(22),5261–5271 (2010).
    • 19  Cancer Genome Atlas Research Network. Integrated genomic analyses of ovarian carcinoma. Nature474(7353),609–615 (2011).
    • 20  Bowtell DD. The genesis and evolution of high-grade serous ovarian cancer. Nat. Rev. Cancer10(11),803–808 (2010).
    • 21  Kuo KT, Mao TL, Jones S et al. Frequent activating mutations of PIK3CA in ovarian clear cell carcinoma. Am. J. Pathol.174(5),1597–1601 (2009).
    • 22  Jones S, Wang TL, Shih Ie M et al. Frequent mutations of chromatin remodeling gene ARID1A in ovarian clear cell carcinoma. Science330(6001),228–231 (2010).
    • 23  Wiegand KC, Shah SP, Al-Agha OM et al.ARID1A mutations in endometriosis-associated ovarian carcinomas. N. Engl. J. Med.363(16),1532–1543 (2010).
    • 24  Cuatrecasas M, Villanueva A, Matias-Guiu X, Prat J. K-RAS mutations in mucinous ovarian tumors: a clinicopathologic and molecular study of 95 cases. Cancer79(8),1581–1586 (1997).
    • 25  Gilks CB, Prat J. Ovarian carcinoma pathology and genetics: recent advances. Hum. Pathol.40(9),1213–1223 (2009).
    • 26  Piek JM, Torrenga B, Hermsen B et al. Histopathological characteristics of BRCA1- and BRCA2-associated intraperitoneal cancer: a clinic-based study. Fam. Cancer2(2),73–78 (2003).
    • 27  Geisler JP, Hatterman-Zogg MA, Rathe JA, Buller RE. Frequency of BRCA1 dysfunction in ovarian cancer. J. Natl Cancer Inst.94(1),61–67 (2002).
    • 28  Hilton JL, Geisler JP, Rathe JA, Hattermann-Zogg MA, Deyoung B, Buller RE. Inactivation of BRCA1 and BRCA2 in ovarian cancer. J. Natl Cancer Inst.94(18),1396–1406 (2002).
    • 29  Lim Sl, Smith P, Syed N et al. Promoter hypermethylation of FANCF and outcome in advanced ovarian cancer. Br. J. Cancer98(8),1452–1456 (2008).
    • 30  Wang Z, Li M, Lu S, Zhang Y, Wang H. Promoter hypermethylation of FANCF plays an important role in the occurrence of ovarian cancer through disrupting Fanconi anemia–BRCA pathway. Cancer Biol. Ther.5(3),256–260 (2006).
    • 31  D’Andrea AD. The Fanconi anemia/BRCA signaling pathway: disruption in cisplatin-sensitive ovarian cancers. Cell Cycle2(4),290–292 (2003).
    • 32  Soegaard M, Kjaer SK, Cox M et al.BRCA1 and BRCA2 mutation prevalence and clinical characteristics of a population-based series of ovarian cancer cases from Denmark. Clin. Cancer Res.14(12),3761–3767 (2008).
    • 33  Risch HA, McLaughlin JR, Cole De et al. Population BRCA1 and BRCA2 mutation frequencies and cancer penetrances: a kin-cohort study in Ontario, Canada. J. Natl Cancer Inst.98(23),1694–1706 (2006).
    • 34  Shaw PA, McLaughlin JR, Zweemer RP et al. Histopathologic features of genetically determined ovarian cancer. Int. J. Gynecol. Pathol.21(4),407–411 (2002).
    • 35  Tan DS, Rothermundt C, Thomas K et al. ‘BRCAness’ syndrome in ovarian cancer: a case–control study describing the clinical features and outcome of patients with epithelial ovarian cancer associated with BRCA1 and BRCA2 mutations. J. Clin. Oncol.26(34),5530–5536 (2008).
    • 36  Vencken PM, Kriege M, Hoogwerf D et al. Chemosensitivity and outcome of BRCA1- and BRCA2-associated ovarian cancer patients after first-line chemotherapy compared with sporadic ovarian cancer patients. Ann. Oncol.22(6),1346–1352 (2011).
    • 37  Gallagher DJ, Konner JA, Bell-McGuinn KM et al. Survival in epithelial ovarian cancer: a multivariate analysis incorporating BRCA mutation status and platinum sensitivity. Ann. Oncol.22(5),1127–1132 (2011).
    • 38  Turner N, Tutt A, Ashworth A. Hallmarks of ‘BRCAness’ in sporadic cancers. Nat. Rev. Cancer4(10),814–819 (2004).
    • 39  Gourley C, Michie Co, Roxburgh P et al. Increased incidence of visceral metastases in Scottish patients with BRCA1/2-defective ovarian cancer: an extension of the ovarian BRCAness phenotype. J. Clin. Oncol.28(15),2505–2511 (2010).
    • 40  Aida H, Takakuwa K, Nagata H et al. Clinical features of ovarian cancer in Japanese women with germ-line mutations of BRCA1. Clin. Cancer Res.4(1),235–240 (1998).
    • 41  Artioli G, Borgato L, Cappetta A et al. Overall survival in BRCA-associated ovarian cancer: case–control study of an Italian series. Eur. J. Gynaecol. Oncol.31(6),658–661 (2010).
    • 42  Ben David Y, Chetrit A, Hirsh-Yechezkel G et al. Effect of BRCA mutations on the length of survival in epithelial ovarian tumors. J. Clin. Oncol.20(2),463–466 (2002).
    • 43  Boyd J, Sonoda Y, Federici MG et al. Clinicopathologic features of BRCA-linked and sporadic ovarian cancer. JAMA283(17),2260–2265 (2000).
    • 44  Buller RE, Shahin MS, Geisler JP, Zogg M, De Young BR, Davis CS. Failure of BRCA1 dysfunction to alter ovarian cancer survival. Clin. Cancer Res.8(5),1196–1202 (2002).
    • 45  Cass I, Baldwin RL, Varkey T, Moslehi R, Narod SA, Karlan BY. Improved survival in women with BRCA-associated ovarian carcinoma. Cancer97(9),2187–2195 (2003).
    • 46  Chetrit A, Hirsh-Yechezkel G, Ben-David Y, Lubin F, Friedman E, Sadetzki S. Effect of BRCA1/2 mutations on long-term survival of patients with invasive ovarian cancer: the national Israeli study of ovarian cancer. J. Clin .Oncol.26(1),20–25 (2008).
    • 47  Hennessy BT, Timms KM, Carey MS et al. Somatic mutations in BRCA1 and BRCA2 could expand the number of patients that benefit from poly (ADP ribose) polymerase inhibitors in ovarian cancer. J. Clin. Oncol.28(22),3570–3576 (2010).
    • 48  Jóhannsson OT, Ranstam J, Borg A, Olsson H. Survival of BRCA1 breast and ovarian cancer patients: a population-based study from southern Sweden. J. Clin. Oncol.16(2),397–404 (1998).
    • 49  Kringen P, Wang Y, Dumeaux V et al.TP53 mutations in ovarian carcinomas from sporadic cases and carriers of two distinct BRCA1 founder mutations; relation to age at diagnosis and survival. BMC Cancer5,134 (2005).
    • 50  Lacour RA, Westin SN, Meyer LA et al. Improved survival in non-Ashkenazi Jewish ovarian cancer patients with BRCA1 and BRCA2 gene mutations. Gynecol. Oncol.121(2),358–363 (2011).
    • 51  Pal T, Permuth-Wey J, Kapoor R, Cantor A, Sutphen R. Improved survival in BRCA2 carriers with ovarian cancer. Fam. Cancer6(1),113–119 (2007).
    • 52  Pharoah PD, Easton DF, Stockton DL, Gayther S, Ponder BA. Survival in familial, BRCA1-associated, and BRCA2-associated epithelial ovarian cancer. United Kingdom Coordinating Committee for Cancer Research (UKCCCR) Familial Ovarian Cancer Study Group. Cancer Res.59(4),868–871 (1999).
    • 53  Ragupathy K, Ferguson M. Pattern and chemosensitivity of ovarian cancer in patients with BRCA1/2 mutations. J. Obstet. Gynaecol.31(2),178–179 (2011).
    • 54  Ramus SJ, Fishman A, Pharoah PD, Yarkoni S, Altaras M, Ponder BA. Ovarian cancer survival in Ashkenazi Jewish patients with BRCA1 and BRCA2 mutations. Eur. J. Surg. Oncol.27(3),278–281 (2001).
    • 55  Rubin SC, Benjamin I, Behbakht K et al. Clinical and pathological features of ovarian cancer in women with germ-line mutations of BRCA1. N. Engl. J. Med.335(19),1413–1416 (1996).
    • 56  Zweemer RP, Verheijen RH, Coebergh JW et al. Survival analysis in familial ovarian cancer, a case control study. Eur. J. Obstet. Gynecol. Reprod. Biol.98(2),219–223 (2001).
    • 57  Dann RB, Deloia JA, Timms KM et al.BRCA1/2 mutations and expression: response to platinum chemotherapy in patients with advanced stage epithelial ovarian cancer. Gynecol. Oncol.125(3),677–682 (2012).
    • 58  Mankoo PK, Shen R, Schultz N, Levine DA, Sander C. Time to recurrence and survival in serous ovarian tumors predicted from integrated genomic profiles. PLoS ONE6(11),e24709 (2011).
    • 59  Yarden RI, Pardo-Reoyo S, Sgagias M, Cowan KH, Brody LC. BRCA1 regulates the G2/M checkpoint by activating Chk1 kinase upon DNA damage. Nat. Genet.30(3),285–289 (2002).
    • 60  Joukov V, Groen AC, Prokhorova T et al. The BRCA1/BARD1 heterodimer modulates ran-dependent mitotic spindle assembly. Cell127(3),539–552 (2006).
    • 61  Lou Z, Minter-Dykhouse K, Chen J. BRCA1 participates in DNA decatenation. Nat. Struct. Mol. Biol.12(7),589–593 (2005).
    • 62  Sankaran S, Crone DE, Palazzo RE, Parvin JD. BRCA1 regulates gamma-tubulin binding to centrosomes. Cancer Biol. Ther.6(12),1853–1857 (2007).
    • 63  Starita LM, Machida Y, Sankaran S et al. BRCA1-dependent ubiquitination of gamma-tubulin regulates centrosome number. Mol. Cell. Biol.24(19),8457–8466 (2004).
    • 64  Drost R, Bouwman P, Rottenberg S et al. BRCA1 RING function is essential for tumor suppression but dispensable for therapy resistance. Cancer Cell.20(6),797–809 (2011).▪ Important study on different domain mutations of BRCA1 inducing different effects on tumor suppression and therapy resistance.
    • 65  Narod SA, Neuhausen S, Vichodez G et al. Rapid progression of prostate cancer in men with a BRCA2 mutation. Br. J. Cancer99(2),371–374 (2008).
    • 66  Ferrone CR, Levine DA, Tang LH et al.BRCA germline mutations in Jewish patients with pancreatic adenocarcinoma. J. Clin. Oncol.27(3),433–438 (2009).
    • 67  Liede A, Karlan BY, Narod SA. Cancer risks for male carriers of germline mutations in BRCA1 or BRCA2: a review of the literature. J. Clin. Oncol.22(4),735–742 (2004).
    • 68  Hahn SA, Greenhalf B, Ellis I et al.BRCA2 germline mutations in familial pancreatic carcinoma. J. Natl Cancer Inst.95(3),214–221 (2003).
    • 69  Moller P, Evans DG, Reis MM et al. Surveillance for familial breast cancer: Differences in outcome according to BRCA mutation status. Int. J. Cancer121(5),1017–1020 (2007).
    • 70  Lee EH, Park SK, Park B et al. Effect of BRCA1/2 mutation on short-term and long-term breast cancer survival: a systematic review and meta-analysis. Breast Cancer Res. Treat.122(1),11–25 (2010).
    • 71  Foulkes WD, Metcalfe K, Sun P et al. Estrogen receptor status in BRCA1- and BRCA2-related breast cancer: the influence of age, grade, and histological type. Clin. Cancer Res.10(6),2029–2034 (2004).
    • 72  Satagopan JM, Boyd J, Kauff ND et al. Ovarian cancer risk in Ashkenazi Jewish carriers of BRCA1 and BRCA2 mutations. Clin. Cancer Res.8(12),3776–3781 (2002).
    • 73  Antoniou A, Pharoah PD, Narod S et al. Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case series unselected for family history: a combined analysis of 22 studies. Am. J. Hum. Genet.72(5),1117–1130 (2003).
    • 74  Prevalence and penetrance of BRCA1 and BRCA2 mutations in a population-based series of breast cancer cases. Anglian Breast Cancer Study Group. Br. J. Cancer83(10),1301–1308 (2000).
    • 75  Hall JM, Lee Mk, Newman B et al. Linkage of early-onset familial breast cancer to chromosome 17q21. Science250(4988),1684–1689 (1990).
    • 76  Miki Y, Swensen J, Shattuck-Eidens D et al. A strong candidate for the breast and ovarian cancer susceptibility gene BRCA1. Science266(5182),66–71 (1994).
    • 77  Sy SM, Huen MS, Chen J. PALB2 is an integral component of the BRCA complex required for homologous recombination repair. Proc. Natl Acad. Sci. USA106(17),7155–7160 (2009).
    • 78  Wooster R, Bignell G, Lancaster J et al. Identification of the breast cancer susceptibility gene BRCA2. Nature378(6559),789–792 (1995).
    • 79  Esashi F, Christ N, Gannon J et al. CDK-dependent phosphorylation of BRCA2 as a regulatory mechanism for recombinational repair. Nature434(7033),598–604 (2005).
    • 80  Ayoub N, Rajendra E, Su X, Jeyasekharan AD, Mahen R, Venkitaraman AR. The carboxyl terminus of BRCA2 links the disassembly of Rad51 complexes to mitotic entry. Curr. Biol.19(13),1075–1085 (2009).
    • 81  Davies OR, Pellegrini L. Interaction with the BRCA2 C terminus protects RAD51-DNA filaments from disassembly by BRC repeats. Nat. Struct. Mol. Biol.14(6),475–483 (2007).
    • 82  Roy R, Chun J, Powell SN. BRCA1 and BRCA2: different roles in a common pathway of genome protection. Nat. Rev. Cancer12(1),68–78 (2011).▪▪ Comprehensive and well-written review highlighting the different roles of BRCA1 and BRCA2 in homologous recombination.
    • 83  Lou Z, Chini CC, Minter-Dykhouse K, Chen J. Mediator of DNA damage checkpoint protein 1 regulates BRCA1 localization and phosphorylation in DNA damage checkpoint control. J. Biol. Chem.278(16),13599–13602 (2003).
    • 84  Hashizume R, Fukuda M, Maeda I et al. The RING heterodimer BRCA1–BARD1 is a ubiquitin ligase inactivated by a breast cancer-derived mutation. J. Biol. Chem.276(18),14537–14540 (2001).
    • 85  Jensen RB, Carreira A, Kowalczykowski SC. Purified human BRCA2 stimulates RAD51-mediated recombination. Nature467(7316),678–683 (2010).
    • 86  Holloman WK. Unraveling the mechanism of BRCA2 in homologous recombination. Nat. Struct. Mol. Biol.18(7),748–754 (2011).
    • 87  Baumann P, Benson FE, West SC. Human Rad51 protein promotes ATP-dependent homologous pairing and strand transfer reactions in vitro. Cell87(4),757–766 (1996).
    • 88  Osher DJ, Kushner YB, Arseneau J, Foulkes WD. Melphalan as a treatment for BRCA-related ovarian carcinoma: can you teach an old drug new tricks? J. Clin. Pathol.64(10),924–926 (2011).
    • 89  Evers B, Schut E, van der Burg E et al. A high-throughput pharmaceutical screen identifies compounds with specific toxicity against BRCA2-deficient tumors. Clin. Cancer Res.16(1),99–108 (2009).
    • 90  Farmer H, McCabe N, Lord CJ et al. Targeting the DNA repair defect in BRCA mutant cells as a therapeutic strategy. Nature434(7035),917–921 (2005).
    • 91  Bryant HE, Schultz N, Thomas HD et al. Specific killing of BRCA2-deficient tumours with inhibitors of poly(ADP-ribose) polymerase. Nature434(7035),913–917 (2005).
    • 92  Chen A. PARP inhibitors: its role in treatment of cancer. Chin. J. Cancer30(7),463–471 (2011).
    • 93  Fong PC, Boss DS, Yap TA et al. Inhibition of poly(ADP-ribose) polymerase in tumors from BRCA mutation carriers. N. Engl. J. Med.361(2),123–134 (2009).
    • 94  Audeh MW, Carmichael J, Penson RT et al. Oral poly(ADP-ribose) polymerase inhibitor olaparib in patients with BRCA1 or BRCA2 mutations and recurrent ovarian cancer: a proof-of-concept trial. Lancet376(9737),245–251 (2010).
    • 95  Fong PC, Yap TA, Boss DS et al. Poly(ADP)-ribose polymerase inhibition: frequent durable responses in BRCA carrier ovarian cancer correlating with platinum-free interval. J. Clin. Oncol.28(15),2512–2519 (2010).
    • 96  Gelmon KA, Tischkowitz M, Mackay H et al. Olaparib in patients with recurrent high-grade serous or poorly differentiated ovarian carcinoma or triple-negative breast cancer: a Phase 2, multicentre, open-label, non-randomised study. Lancet Oncol.12(9),852–861 (2011).
    • 97  Kaye SB, Lubinski J, Matulonis U et al. Phase II, open-label, randomized, multicenter study comparing the efficacy and safety of olaparib, a poly (ADP-ribose) polymerase inhibitor, and pegylated liposomal doxorubicin in patients with BRCA1 or BRCA2 mutations and recurrent ovarian cancer. J. Clin. Oncol.30(4),372–379 (2012).
    • 98  Ledermann J, Harter P, Gourley C et al. Olaparib maintenance therapy in platinum-sensitive relapsed ovarian cancer. N. Engl. J. Med.366(15),1382–1392 (2012).
    • 99  Turner NC Lord CJ, Iorns E et al. A synthetic lethal siRNA screen identifying genes mediating sensitivity to a PARP inhibitor. EMBO J.27(9),1368–1377 (2008).
    • 100  Issaeva N, Thomas HD, Djureinovic T et al. 6-thioguanine selectively kills BRCA2-defective tumors and overcomes PARP inhibitor resistance. Cancer Res.70(15),6268–6276 (2010).
    • 101  Jacquemont C, Taniguchi T. Proteasome function is required for DNA damage response and fanconi anemia pathway activation. Cancer Res.67(15),7395–7405 (2007).
    • 102  Deans AJ, Khanna KK, Mcnees CJ, Mercurio C, Heierhorst J, Mcarthur GA. Cyclin-dependent kinase 2 functions in normal DNA repair and is a therapeutic target in BRCA1-deficient cancers. Cancer Res.66(16),8219–8226 (2006).
    • 103  Dungey FA, Caldecott KW, Chalmers AJ. Enhanced radiosensitization of human glioma cells by combining inhibition of poly(ADP-ribose) polymerase with inhibition of heat shock protein 90. Mol. Cancer Ther.8(8),2243–2254 (2009).
    • 104  Chiang JW, Karlan BY, Cass L, Baldwin RL. BRCA1 promoter methylation predicts adverse ovarian cancer prognosis. Gynecol. Oncol.101(3),403–410 (2006).
    • 105  Liu GY, Zhang W. Will Chinese ovarian cancer patients benefit from knowing the BRCA2 mutation status? Chin. J. Cancer31(1),1–4 (2012).