“…Previous studies have indicated an association between IL18-607C/A and -137G/ C polymorphisms and the risk of many malignant tumors, such as esophageal cancer, gastrointestinal cancer, papillary thyroid cancer, hepatocellular carcinoma, prostate carcinoma, and oral squamous cell carcinoma (Liu et al, 2013;Singh et al, 2014;Bao et al, 2015;Chung et al, 2015;Dwivedi et al, 2015b;Li et al, 2015;Yao et al, 2015;Zhu et al, 2016). Singh et al (2014) performed a study on 272 patients with oral squamous cell carcinoma and 185 controls, and reported that the IL18-137G/C genetic variation was correlated with the progression of this cancer, but the -607C/A polymorphism was not.…”