GRIK2 and esophageal squamous cell carcinoma: Most importantly, using molecular subtyping by CNA clusters, mutation panel (ADCY2, CACNA1D, GRIK2, KCNMA1, and KCNQ3), and genes with CNA loss panel (SLN, ACAT1, GUCY1A2), we stratified ESCC patients into distinct prognostic subgroups.