Polymorphisms of Death Pathway Genes FAS and FASL in Esophageal Squamous-Cell Carcinoma

Background: The FAS receptor–ligand system is a key regulator of apoptotic cell death, and loss of FAS expression and gain of FAS ligand (FASL) expression play important roles in the development and progression of cancer. Single-nucleotide polymorphisms in the promoter region of the FAS (G or A at position –1377 [FAS –1377G/A] and A or G at position –670 [FAS –670A/G]) and FASL (T or C at position –844 [FASL –844T/C]) genes alter the transcriptional activity of these genes. We examined the association between these polymorphisms and risk of the development and metastasis of esophageal squamous-cell carcinoma. Methods: Genotypes of 588 case patients with esophageal squamous-cell carcinoma and 648 control subjects were determined by polymerase chain reaction–based restriction fragment length polymorphism. Associations with the risk of esophageal squamous-cell carcinoma were estimated by logistic regression. All statistical tests were two-sided. Results: We observed a statistically significantly increased risk of esophageal squamous-cell carcinoma associated with the FAS –1377AA (odds ratio [OR] = 1.79, 95% confidence interval [CI] = 1.29 to 2.48; P