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// Tomoko Yoshihama 1, 2 , Koya Fukunaga 1 , Akira Hirasawa 2 , Hiroyuki Nomura 2 , Tomoko Akahane 2 , Fumio Kataoka 2 , Wataru Yamagami 2 , Daisuke Aoki 2 and Taisei Mushiroda 1 1 Laboratory for Pharmacogenomics, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan 2 Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan Correspondence to: Taisei Mushiroda, email: mushiroda@riken.jp Keywords: pharmacogenomics; carboplatin; ovarian cancer; next-generation sequencer; targeted resequencing Received: April 07, 2018 Accepted: June 13, 2018 Published: July 03, 2018 ABSTRACT Purpose: To find genetic variants that predicted toxicity and/or efficacy of paclitaxel plus carboplatin combination therapy (TC therapy). Patients and methods: In a retrospective case-control study, we analyzed 320 patients who had received TC therapy for gynecological cancers (ovarian, fallopian tube, peritoneal, uterine, and cervical cancers) and collected their germline DNA. We performed a comprehensive pharmacogenomic analysis using a targeted resequencing panel of 100 pharmacogenes. For 1,013 variants passing QC, case-control association studies and survival analyses were conducted. Results: GSTP1 rs1695 showed the smallest p value for hematotoxicity association, and the 105 Ile wild type allele had a significantly higher risk of severe hematotoxicity (neutropenia G4, thrombocytopenia ≥ G3 and anemia ≥ G3) than the 105 Val allele (p=0.00034, odds ratio=5.71 (95% confidence interval:1.77-18.44)). Next, we assessed 5-year progression-free survival (PFS) and overall survival (OS) in 56 advanced ovarian cancer patients who received tri-weekly TC as a first-line chemotherapy. Patients with the 105 Ile/ 105 Ile genotype showed significantly better PFS (p=0.00070) and OS (p=0.0012) than those with the 105 Ile/ 105 Val or 105 Val/ 105 Val genotype. Conclusion: Our study indicates that the GSTP1 rs1695 105 Ile/ 105 Ile genotype is associated with both severe hematotoxicity and high efficacy of TC therapy, identifying a possible prognostic indicator for patients with TC therapy.

Pathogenic germline BRCA1, BRCA2 (BRCA1/2), and several other gene variants predispose women to primary ovarian, fallopian tube, and peritoneal carcinoma (OC), although variant frequency and relevance information is scarce in Japanese women with OC. Using targeted panel sequencing, we screened 230 unselected Japanese women with OC from our hospital-based cohort for pathogenic germline variants in 75 or 79 OC-associated genes. Pathogenic variants of 11 genes were identified in 41 (17.8%) women: 19 (8.3%; BRCA1), 8 (3.5%; BRCA2), 6 (2.6%; mismatch repair genes), 3 (1.3%; RAD51D), 2 (0.9%; ATM), 1 (0.4%; MRE11A), 1 (FANCC), and 1 (GABRA6). Carriers of BRCA1/2 or any other tested gene pathogenic variants were more likely to be diagnosed younger, have first or second-degree relatives with OC, and have OC classified as high-grade serous carcinoma (HGSC). After adjustment for these variables, all 3 features were independent predictive factors for pathogenic variants in any tested genes whereas only the latter two remained for variants in BRCA1/2. Our data indicate similar variant prevalence in Japanese patients with OC and other ethnic groups and suggest that HGSC and OC family history may facilitate genetic predisposition prediction in Japanese patients with OC and referring high-risk patients for genetic counseling and testing.