Targeting DNA Repair in Cancer: Beyond PARP Inhibitors

Germline aberrations in critical DNA-repair and DNA damage-response (DDR) genes cause cancer predisposition, whereas various tumors harbor somatic mutations causing defective DDR/DNA repair. The concept of synthetic lethality can be exploited in such malignancies, as exemplified by approval of poly(ADP-ribose) polymerase inhibitors for treating BRCA1/2-mutated ovarian cancers. Herein, we detail how cellular DDR processes engage various proteins that sense DNA damage, initiate signaling pathways to promote cell-cycle checkpoint activation, trigger apoptosis, and coordinate DNA repair. We focus on novel therapeutic strategies targeting promising DDR targets and discuss challenges of patient selection and the development of rational drug combinations. $\textbf{SIGNIFICANCE}$: Various inhibitors of DDR components are in preclinical and clinical development. A thorough understanding of DDR pathway complexities must now be combined with strategies and lessons learned from the successful registration of PARP inhibitors in order to fully exploit the potential of DDR inhibitors and to ensure their long-term clinical success. Cancer Discov; 7(1); 20-37. ©2016 AACRJ.S. Brown, B. O'Carrigan, and T.A. Yap acknowledge support from the Experimental Cancer Medicine Centre (to The Institute of Cancer Research) and the National Institute for Health Research Biomedical Research Centre (jointly to the Royal Marsden NHS Foundation Trust and The Institute of Cancer Research). Research in The Jackson laboratory is funded by Cancer Research UK (CRUK) program grant number C6/A18796. Core funding is provided by CRUK (C6946/A14492) and the Wellcome Trust (WT092096). S.P. Jackson receives his salary from the University of Cambridge, UK, supplemented by CRUK

Testosterone deficiency and quality of life in Australasian testicular cancer survivors: a prospective cohort study

This is the first prospective study in a contemporary Australian/New Zealand population to determine the prevalence of testosterone deficiency in testicular cancer survivors at 12 months from treatment, and any association with poorer quality of life. Hormone assays from 54 evaluable patients in a prospective cohort study revealed biochemical hypogonadism in 18 patients (33%) and low-normal testosterone in 13 patients (24%). We found no association between testosterone levels and quality of life (all P > 0.05). Hypogonadal patients should be considered for testosterone replacement to prevent long-term morbidity.B. O'Carrigan, M. Fournier, I. N. Olver, M. R. Stockler, H. Whitford, G. C. Toner, D. B. Thomson, I. D. Davis, F. Hanning, N. Singhal, C. Underhill, P. Clingan, A. McDonald, A. Boland, P. Grimison and Australian and New Zealand Urogenital and Prostate Cancer Trials Grou