Review
Copyright ©2013 Baishideng. All rights reserved.
World J Clin Oncol. Feb 10, 2013; 4(1): 14-24
Published online Feb 10, 2013. doi: 10.5306/wjco.v4.i1.14
Ovarian cancer and DNA repair: DNA ligase IV as a potential key
Joana Assis, Deolinda Pereira, Rui Medeiros
Joana Assis, Rui Medeiros, Molecular Oncology GRP-CI, Portuguese Institute of Oncology, 4200-072 Porto, Portugal
Joana Assis, Rui Medeiros, Research Department of Portuguese League against Cancer (NRNorte), 4200-072 Porto, Portugal
Deolinda Pereira, Oncology Department, Portuguese Institute of Oncology, 4200-072 Porto, Portugal
Deolinda Pereira, Rui Medeiros, ICBAS, Abel Salazar Institute for the Biomedical Sciences, University of Porto, 4200-072 Porto, Portugal
Rui Medeiros, CEBIMED, Faculty of Health Sciences of Fernando Pessoa University, 4200-150 Porto, Portugal
Author contributions: Assis J and Medeiros R designed the structure of the review; Assis J wrote the initial draft and the final version of the manuscript; Pereira D and Medeiros R critically revised the manuscript for important intellectual content; Medeiros R supervised the study and approved the version to be published.
Supported by Research Department of Portuguese League against Cancer (NRNorte) and Minister of Health of Portugal (CFICS-45/2007)
Correspondence to: Rui Medeiros, Professor, Molecular Oncology GRP-CI, Portuguese Institute of Oncology, R. Dr António Bernardino de Almeida, 4200-072 Porto, Portugal. ruimedei@ipoporto.min-saude.pt
Telephone: +351-22-5084000 Fax: +351-22-5084001
Received: September 27, 2012
Revised: January 7, 2013
Accepted: January 17, 2013
Published online: February 10, 2013
Processing time: 174 Days and 11.5 Hours
Abstract

Ovarian cancer (OC) is the sixth most common cancer and the seventh cause of death from cancer in women. The etiology and the ovarian carcinogenesis still need clarification although ovulation may be determinant due to its carcinogenic role in ovarian surface epithelium. The link between ovarian carcinogenesis and DNA repair is well established and it became clear that alterations in DNA damage response may affect the risk to develop OC. Polymorphisms are variations in the DNA sequence that exist in normal individuals of a population and are capable to change, among other mechanisms, the balance between DNA damage and cellular response. Consequently, genetic variability of the host has a great role in the development, progression and consequent prognosis of the oncologic patient as well as in treatment response. Standard treatment for OC patients is based on cytoreductive surgery, followed by chemotherapy with a platinum agent and a taxane. Although 80% of the patients respond to the first-line therapy, the development of resistance is common although the mechanisms underlying therapy failure remain mostly unknown. Because of their role in oncology, enzymes involved in the DNA repair pathways, like DNA Ligase IV (LIG4), became attractive study targets. It has been reported that variations in LIG4 activity can lead to a hyper-sensitivity to DNA damage, deregulation of repair and apoptosis mechanisms, affecting the susceptibility to cancer development and therapy response. To overcome resistance mechanisms, several investigations have been made and the strategy to target crucial molecular pathways, such as DNA repair, became one of the important areas in clinical oncology. This review aims to elucidate the link between DNA repair and OC, namely which concerns the role of LIG4 enzyme, and how genetic polymorphisms in LIG4 gene can modulate the activity of the enzyme and affect the ovarian carcinogenesis and treatment response. Moreover, we try to understand how LIG4 inhibition can be a potential contributor for the development of new cancer treatment strategies.

Keywords: Ovarian Cancer; DNA Repair; DNA ligase IV; Polymorphisms; Susceptibility; Treatment response