Background: Cell cycle deregulation is a major component of carcinogenesis. The p53 tumor suppressorgene plays an important role in regulating cell cycle arrest, and mouse double minute 2 (MDM2) is a keyregulator of p53 activity and degradation. Abnormal expression of p53 and MDM2 occurs in various cancersincluding lung cancer.
Methods: We investigated the distribution of the p53 Arg72Pro (rs1042522) and MDM2SNP309 (rs2279744) genotypes in patients and healthy control subjects to assess whether these single nucleotidepolymorphisms (SNPs) are associated with an increased risk of lung adenocarcinomas in Chinese female nonsmokers.Genotypes of 764 patients and 983 healthy controls were determined using the TaqMan SNP genotypingassay.
Results: The p53 Pro/Pro genotype (adjusted OR = 1.55, 95% CI = 1.17–2.06) significantly correlated withan increased risk of lung adenocarcinoma, compared with the Arg/Arg genotype. An increased risk was also notedfor MDM2 GG genotype (adjusted OR = 1.68, 95% CI = 1.27–2.21) compared with the TT genotype. Combinedp53 Pro/Pro and MDM2 GG genotypes (adjusted OR = 2.66, 95% CI = 1.54–4.60) had a supermultiplicativeinteraction with respect to lung adenocarcinoma risk. We also found that cooking oil fumes, fuel smoke, andpassive smoking may increase the risk of lung adenocarcinomas in Chinese female non-smokers who carry p53or MDM2 mutant alleles.
Conclusions: P53 Arg72Pro and MDM2 SNP309 polymorphisms, either alone or incombination, are associated with an increased lung adenocarcinoma risk in Chinese female non-smokers.