Abstract

Introduction: Breast cancer is a malignant proliferation of epithelial cells that cover the breast ducts or lobes. The accumulation of DNA damage is considered as a major factor in breast cancer. One of the most important defense mechanisms is Nucleotide Excision Repair (NER). Dysregulation of DNA repair genes expression is important for breast carcinogenesis. XPC(Xeroderma pigmentosum, complementation group C) is an important NER gene that recognizes the damage caused by a variety of bulky DNA adducts. Poly AT (PAT) sequence is one of important polymorphisms in this gene.

Objective: This study investigated the relationship of the XPC PAT polymorphism with breast cancer.

Materials and Methods: In this Case-Control study, we analyzed 79 patients and 120 healthy controls. The genotyping of PAT polymorphism was performed using polymerase chain reaction (PCR) and statistical analyses were conducted by theMedCalc statistical software (version 12.1).

Results: Among cancer cases, the distributions of PAT-/-, PAT-/+ and PAT+/+ genotypes were 66%, 10%, and 24%, respectively. Among controls, the distributions of PAT-/-, PAT-/+ and PAT+/+ genotypes were 71%, 19%, 10%, respectively. The genotype frequencies did differ significantly between patients and controls (P=0.01).The frequency of PAT+ allele was significantly higher in patients (0.30) than in the controls (0.20), (P=0.02).

Conclusion: Our study suggests that XPC Poly AT sequence polymorphism might be a genetic predisposing factor for breast Cancer. However, larger population-based studies are needed for clarifying the role of XPC gene polymorphism in breast Cancer.