mutational analysis of hogg1 gene promoter in patients with non-small cell lung cancer

Abstract

Background and objective 8-hydroxygumine DNA glycosylase 1 (OGG1) is a DNA repair enzyme, which can repair damaged DNA by excising 8-dihydro-8-oxoguanine (8-OH-G). Polymorphisms in human OGG1 gene (hOGG1) may alter glycosylase activity, thereby affects its repair to the damaged DNA, resulting in contribution to carcinogenesis. However, an association of genetic variants of hOGG1 promoter with non-small cell lung cancer (NSCLC) remains unclear. The present study aims to explore whether there are mutations in the promoter region of hOGG1 and the association of the potential genetic variants with NSCLC. Methods Forty lung cancer patients were enrolled from January, 2003 to December, 2005 in the first affiliated hospital of Soochow University. PCR-SSCP followed by direct sequencing were performed to detect mutations within the promoter region of the hOGG1 gene in NSCLC and corresponding paracancerous lung tissues. Results No abnormal mutation was found in the promoter region of the hOGG1 gene in 40 patients with NSCLC. However, a SNP rs159153 in hOGG1 was significantly associated with higher TNM stage (P=0.008). Moreover, lower frequency of lymph node metastasis was observed in smoker patients with NSCLC (P=0.034). Conclusion The SNP rs159153 in the promoter region of the hOGG1 gene and smoking history may effectively forebode the aggressiveness and metastatic potential of NSCLC.