The Correlation Between -1310c/g Polymorphism Located In The Promoter Region Of Ku70 Gene And Breast Cancer

Objective:The aim of the present study was undertaken is to determine the distribution of c.-1310 C>G located in the coding and promoter regions of Ku70 polymorphism in breast cancer patients and healthy control group in order to evaluate the potential association between Ku70 c.-1310 C>G single nucleotide polymorphism and breast cancer risk in Chinese women. Here we carried out a case-control study to investigate association of this polymorphism with breast cancer in Chinese population, to provide the evidence for early diagnosis, therapy and prevention of breast cancer.Methods:This hospital-based case-control study included 293 breast cancer patients and 301 healthy controls. All the individuals were collected from the Chinese Han people and were randomly selected. Genomic DNA was extracted from blood sample, and the polymerase chain reaction-restriction fragment length polymorphism technique was used to detect the genotype and allele frequencies of Ku70-1310 C/G polymorphism.Results:1. In healthy han women in China, the frequency of Ku70 c.-1310 C>G polymorphism C allele is 78.2%, the frequency of G allele is 21.8%. The distribution of CC, CG, GG allelotype 59.5%, 37.5%, 3%. 2. In breast cancer cases, the frequency of Ku70 c.-1310 C>G polymorphism G allele is 30.2%,higher than 21.8% of healthy individuals. Individuals with Ku70-1310 C/G or G/G genotype were at higher risk of breast cancer as compared with subjects carrying genotype C/C (OR = 1.43, p = 0.038; OR = 3.53, p = 0.002, respectively).3. The patient population has been divided in two groups based on menopausal status. the variant genotypes of CG + GG and G allele were both associated with a significantly increased risk of breast cancer among premenopausal women (ORCG+GG = 1.724, p = 0.003; ORG allele = 1.637, p = 0.001) but not in postmenopausal women (ORCG+GG = 1.297, p = 0.302; ORG allele = 1.383, p = 0.107).4. The GG genotype was significantly associated with elevated risk of ER-negative breast cancer, ER-positive breast cancer, PR- positive breast cancer, HER 2-negative breast cancer and HER 2-positive breast cancer. But, no association could be made between GG genotype and risk of PR-negative breast cancer.5. There were no significant differences in genotypes distribution between the three groups which were divided base on the lymph node metastasis status (p = 0.987) .Conclusions:G allele of Ku70 polymorphism (rs2267437) is a genetic susceptibility factor for the development of breast cancer in a Chinese population. Ku70 c.-1310 C>G polymorphism is significantly associated with elevated risk of breast cancer.