Suramin sensitizing cells to ionizing radiation by inactivating DNA-dependent protein kinase

Ku80 gene G-1401T promoter polymorphism and risk of gastric cancer

AIM: To evaluate the possible relationship between the Ku80 gene polymorphism and the risk of gastric cancer in China.

METHODS: In this hospital-based case-control study of gastric cancer in Jiangsu Province, China, we investigated the association of the Ku80 G-1401T (rs828907) polymorphism with gastric cancer risk. A total of 241 patients with gastric cancer and 273 age- and sex-matched control subjects were genotyped and analyzed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS: The frequencies of genotypes GG, GT and TT were 65.6%, 22.8% and 11.6% in gastric cancer cases, respectively, and 75.8%, 17.6% and 6.6% in controls, respectively. There were significant differences between gastric cancer and control groups in the distribution of their genotypes (P = 0.03) and allelic frequencies (P = 0.002) in the Ku80 promoter G-1401T polymorphism.

CONCLUSION: The T allele of Ku80 G-1401T may be associated with the development of gastric cancer.

Association between DNA double strand break gene Ku80 polymorphisms and oral cancer susceptibility

The DNA double strand break repair gene Ku80 is thought to play a major role in the caretaking of the overall genome stability. It is very possible that defective in double strand break repair capacity can lead to human carcinogenesis. Thus, the polymorphic variants of Ku80 were firstly investigated regarding their association with oral cancer susceptibility. In this hospital-based case-control study, the association of Ku80 promoter G-1401T (rs828907), promoter C-319T (rs11685387), and intron19 (rs9288518) polymorphisms with oral cancer risk in a Taiwanese population was investigated. 600 patients with oral cancer and 600 age- and gender-matched healthy controls recruited were genotyped and analyzed by PCR-RFLP method. There were significant differences between oral cancer and control groups in the distributions of their genotypes (P=0.0038) and allelic frequencies (P=0.0044) in the Ku80 promoter G-1401T polymorphism. In the other two polymorphisms, there was no difference between both groups in the distribution of either genotype or allelic frequency. There is a synergistic gene-environmental interaction between Ku80 and areca chewing. Compared with G/G genotype in Ku80 promoter G-1401T, the G/T plus T/T significantly enhanced the risk only in the areca chewers (odds ratio=1.603; 95% confidence interval=1.053-2.011), not in the non-areca chewers. In conclusion, the Ku80 promoter G-1401T is correlated with oral cancer susceptibility and this polymorphism may be a useful marker for oral cancer prevention and early detection.