MDM2 309T>G polymorphism and risk of lung cancer in a Korean population

Background: The MDM2 protein plays an important role in regulating cell proliferation and apoptosis by interaction with multiple proteins including p53 and Rb. A polymorphism (309T>G) in the MDM2 promoter has been shown to result in higher levels of MDM2 RNA and protein. In order to evaluate the association of the MDM2 309T>G polymorphism and lung cancer risk, we carried out a case-control study in a Korean population. Methods: The MDM2 genotypes were determined in 582 lung cancer patients and in 582 healthy control subjects who were frequency matched for age and gender. Results: The distribution of the MDM2 309T>G genotypes was not significantly different between overall lung cancer cases and controls. However, when the cases were categorized by tumor histology, the 309GG genotype was associated with a significantly increased risk of adenocarcinoma (adjusted OR = 1.91, 95% CI = 1.16-3.14, P = 0.01) compared to the 309TT genotype. In addition, the risk of adenocarcinoma increased as the number of 309G alleles increased (P_trend = 0.01). Conclusion: Our findings suggest that the MDM2 309T>G polymorphism may be used as a marker for genetic susceptibility to adenocarcinoma of the lung.