CCND1 and esophageal squamous cell carcinoma: Several recent studies have elucidated that certain molecules, such as p53, cyclin D1 (CCND1) and FAS, have important roles in tumourigenesis and the development of the ESCC (Hollstein et al, 1990; Adélaide et al, 1995; Shinozaki et al, 1996; Gratas et al, 1998).