Most previous studies indicate that decreased FAS expression and/or increased FASL expression was a common feature of malignant transformation and an early event associated with the development of most human cancers, including gastric cancer, prostate cancer, nasopharyngeal carcinoma, renal cell carcinoma and oral squamous cell carcinoma [25–27,55,66]. The gene discussed is FASLG; the disease is oral cavity squamous cell carcinoma.