Single nucleotide polymorphisms of MAGE-A3 gene and its clinical implications in Chinese patients with non-small cell lung cancer（NSCLC）

Background: Available study revealed advanced tumors have a higher expression rate of MAGE-A3 gene which has a lot of single nucleotide polymorphism(SNP) loci with polymorphisms. This study aimed to analyze the allele frequency of SNP loci in MAGE-A3 gene and investigate the relationship between MAGE-A3 gene polymorphisms and clinical factors.Methods: Tumor samples of a cohort of 191 NSCLC patients were collected. EGFR m RNA expression were detected by q RT-PCR. SNPs in whole length of MAGE-A3 gene were detected by direct sequencing. Frequencies of the SNPs were correlated to gene expression, mutation status of EGFR and clinical factors.Results: Sequencing analysis confirmed that allele frequencies of genotypes on SNP loci rs5970360, rs5925210, rs5970361, rs5925211 and rs35123853 were CC(0.681)/CT(0.319), CC(0.660)/CG(0.340), CC(0.681)/CA(0.319), AA(0.984)/AT(0.016) and GG(1.000)/GA(0.000), respectively, which were different from the frequencies and genotypes of MAGE-A3 in SNP database. Chi-square tests showed the EGFR mR NA expression level had significant correlation with the genotypes of SNP loci rs5970360 and rs5925210. But all frequencies of each MAGE-A3 SNPs were not found significantly different between EGFR mutant and wild type patients. MAGE-A3 gene polymorphisms had no significant effects on survival of NSCLC patients.Conclusions: Chinese patients with NSCLC had different SNP patterns of MAGE-A3 in comparison with those in international SNP database. These MAGE-A3 SNP loci might have not prognostic significance. MAGE-A3 SNP loci rs5970360 and rs5925210 might be predictive for EGFR m RNA expression levels and helpful to the selection of patients for epidermal growth factor receptor(EGFR) targeted immunotherapy.