Objective: To investigate the association of single nucleotide polymorphism (SNP) of manganese superoxide dismutase (MnSOD) gene with carcinogenesis and progression of esophageal squamous cell carcinoma.
Methods: The MnSOD9 T-->C SNP was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 103 patients with esophageal squamous cell carcinoma and 195 healthy controls.
Results: A significant difference was observed in the MnSOD allelotype distribution among esophageal squamous cell carcinomas and healthy controls (chi(2) = 4.645, P < 0.05). Individuals with the 9 C allele had a significantly higher risk to develop esophageal squamous cell carcinoma compared with those with the TT allele. The frequency of C allelotype among patients with lesions of different lengths (</= 5 cm and > 5 cm) was 16.3% and 36.7%, respectively. A significant difference was observed in the MnSOD allelotype distribution between patients with lesions of different lengths (chi(2) = 5.147, P < 0.05). No significant association of the MnSOD polymorphism at 9 T-->C with the tumor site, maximal length and clinical staging was found in esophageal squamous cell carcinoma.
Conclusion: Single nucleotide polymorphism (SNP) of MnSOD gene may be correlated with the susceptibility and disease progression of esophageal squamous cell carcinoma, and may become a tumor marker for prediction of this cancer.