Behind XRCC1 Arg399Gln polymorphism: protection factor of laryngeal cancer

Laryngeal cancer is the second most common head and neck cancer worldwide, which has been considering a serious global health problem due to the high morbidity and mortality. Tumour risk factors include the DNA repair gene polymorphisms, but their contribution for metastasis and/or second primary tumour development has been seldom investigated. Objective (s): The present study evaluated the possible association between the DNA repair gene polymorphisms and laryngeal cancer risk, metastasis and/or second primary tumour in a hospital-based case-control study that comprised 149 laryngeal cancer patients and 448 controls from Heliópolis Hospital, São Paulo, Brazil. Design: The single nucleotide polymorphisms (SNPs) of the genes XRCC1 (Arg194Trp; Arg399Gln), XPD (Lys751Gln) and XRCC3 (Thr241Met) were analysed by TaqMan SNP Genotyping Assays. Results: The heterozygous genotype (OR 0.63, 95% CI 0.41-0.96) as well as the mutated homozygous genotype (OR 0.29, 95% CI 0.13-0.66) of XRCC1 (Arg399Gln) decreased the laryngeal cancer risk, even though none of the genes polymorphisms was associated with metastasis and/or second primary tumour development. Conclusion: The determination of the XRCC1 (399Gln) genotype might be applied as a molecular predictor of laryngeal cancer among individuals who are highly exposed to cigarette smoking carcinogens and improve the prognostic of the disease.