NBS1 rs2735383 polymorphism is associated with an increased risk of laryngeal carcinoma

Abstract

Background: Nijmegen breakage syndrome 1 (NBS1), as a key protein in the DNA double-strand breaks (DSBs) repair pathway, plays an important role in maintaining genomic stability. Although single nucleotide polymorphisms (SNPs) in NBS1 have frequently been studied in multiple cancers, the relationships of two functional NBS1 polymorphisms (rs2735383 and rs1805794) with laryngeal carcinoma are yet unclear. Therefore, in the present study, we performed a case-control study including 342 cases and 345 controls to analyze the associations between two polymorphisms of NBS1 and the risk of laryngeal carcinoma. Methods: We used the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to determine the genotypes of the functional SNPs in NBS1 gene. Results: In comparison with the homozygous rs2735383GG genotype, the CC genotype was significantly associated with an increased risk of laryngeal carcinoma (adjusted OR=1.884, 95%CI=1.215-2.921). The rs2735383C variant genotypes (GC+CC) conferred a 1.410-fold increased risk of laryngeal carcinoma (adjusted OR=1.410, 95%CI=1.004-1.980). Furthermore, when compared to rs2735383GG genotype in laryngeal carcinoma tissues, the combined GC and CC genotypes exerted a significantly lower mRNA level of NBS1 (P=0.003). In contrast, no significant association was found between rs1805794G>C polymorphism and cancer risk (adjusted OR=1.074, 95%CI=0.759-1.518 for GC; adjusted OR=1.100, 95%CI=0.678-1.787 for CC; adjusted OR=1.079, 95%CI=0.774-1.505 for GC+CC). Conclusions: These findings indicate that rs2735383G>C polymorphism in NBS1 may play a crucial role in the development of laryngeal carcinoma.