FBXO4 and esophageal squamous cell carcinoma: The screening of human esophageal squamous cell carcinoma (ESCC) tissues identified the existence of Fbxo4 mutations, such as S8R, S12L, P13S, L23Q, and G30N in D domain, and P76T mutation in F-box domain, leading to loss of function of Fbxo4 [21].