[Abnormalities of DNA repair and gynecological cancers].

The demonstration of frequent defects in the DNA damage response in high grade ovarian cancer has paved the way for a new therapeutic approach aimed at exploiting this unique vulnerability. The efficacy of poly (ADP) ribose polymerase inhibitors (PARPi) in patients with homologous recombination (HR) DNA repair deficient ovarian cancer (OC) resulting from a BRCA1/2 mutation has provided the proof of concept for synthetic lethality. Thus, olaparib is now approved by the EMA as maintenance therapy after response to a platinum regimen for patients with recurrent, platinum-sensitive, high-grade serous, BRCA1/2-mutated ovarian cancer. Furthermore, several recent trials in OC have demonstrated that the benefit of PARPi may not be limited to patients with BRCA mutations. These data, combined with genomic studies suggesting that a significant proportion of OC may harbor somatic and germline alterations in other HR genes open huge perspectives for exploiting DNA repair as a therapeutic strategy. The current priorities are to (i) determine whether new biomarkers of homologous recombination deficiency may identify the BRCA wild-type subset likely to derive benefit from PARPi; (ii) to determine whether the efficacy of PARPi can be improved by combinatorial strategies (with chemotherapy, radiotherapy, immunotherapy, anti-angiogenesis or DNA repair inhibitors) and (iii) to develop new approaches exploiting DNA repair deficiencies in ovarian and other gynecological tumors.

Auguste A ，Leary A 《-》

[From poly(ADP-ribose) discovery to PARP inhibitors in cancer therapy].

Poly(ADP-ribosyl)ation is a post-translational modification catalyzed by poly(ADP-ribose) polymerases. PARP-1 is a molecular sensor of DNA breaks, playing a key role in the spatial and temporal organization of their repair, contributing to the maintenance of genome integrity and cell survival. The fact that PARP inhibition impairs efficacy of break repair has been exploited as anticancer strategies to potentiate the cytotoxicity of anticancer drugs and radiotherapy. Numerous clinical trials based on this innovative approach are in progress. PARP inhibition has also proved to be exquisitely efficient to kill tumour cells deficient in double strand break repair by homologous recombination, such as cells mutated for the breast cancer early onset genes BRCA1 or BRCA2, by synthetic lethality. Several phase III clinical trials are in progress for the treatment of breast and ovarian cancers with BRCA mutations and the PARP inhibitor olaparib has just been approved for advanced ovarian cancers with germline BRCA mutation. This review recapitulates the history from the discovery of poly(ADP-ribosyl)ation reaction to the promising therapeutic applications of its inhibition in innovating anticancer strategies. Benefits, hopes and obstacles are discussed.

Schreiber V ，Illuzzi G ，Héberlé E ，Dantzer F ... -  《-》

Clinical Application of Poly(ADP-Ribose) Polymerase Inhibitors in High-Grade Serous Ovarian Cancer.

: High-grade serous ovarian cancer is characterized by genomic instability, with one half of all tumors displaying defects in the important DNA repair pathway of homologous recombination. Given the action of poly(ADP-ribose) polymerase (PARP) inhibitors in targeting tumors with deficiencies in this repair pathway by loss of BRCA1/2, ovarian tumors could be an attractive population for clinical application of this therapy. PARP inhibitors have moved into clinical practice in the past few years, with approval from the Food and Drug Administration (FDA) and European Medicines Agency (EMA) within the past 2 years. The U.S. FDA approval of olaparib applies to fourth line treatment in germline BRCA-mutant ovarian cancer, and European EMA approval to olaparib maintenance in both germline and somatic BRCA-mutant platinum-sensitive ovarian cancer. In order to widen the ovarian cancer patient population that would benefit from PARP inhibitors, predictive biomarkers based on a clear understanding of the mechanism of action are required. Additionally, a better understanding of the toxicity profile is needed if PARP inhibitors are to be used in the curative, rather than the palliative, setting. We reviewed the development of PARP inhibitors in phase I-III clinical trials, including combination trials of PARP inhibitors and chemotherapy/antiangiogenics, the approval for these agents, the mechanisms of resistance, and the outstanding issues, including the development of biomarkers and the rate of long-term hematologic toxicities with these agents. The poly(ADP-ribose) polymerase (PARP) inhibitor olaparib has recently received approval from the Food and Drug Administration (FDA) and European Medicines Agency (EMA), with a second agent (rucaparib) likely to be approved in the near future. However, the patient population with potential benefit from PARP inhibitors is likely wider than that of germline BRCA mutation-associated disease, and biomarkers are in development to enable the selection of patients with the potential for clinical benefit from these agents. Questions remain regarding the toxicities of PARP inhibitors, limiting the use of these agents in the prophylactic or adjuvant setting until more information is available. The indications for olaparib as indicated by the FDA and EMA are reviewed.

Parkes EE ，Kennedy RD 《-》

Cediranib, a pan-VEGFR inhibitor, and olaparib, a PARP inhibitor, in combination therapy for high grade serous ovarian cancer.

Ivy SP ，Liu JF ，Lee JM ，Matulonis UA ，Kohn EC ... -  《-》

New Targeted Agents in Gynecologic Cancers: Synthetic Lethality, Homologous Recombination Deficiency, and PARP Inhibitors.

Liu FW ，Tewari KS 《-》