SMS and head and neck squamous cell carcinoma: As a hub gene in the model of Arg and Pro metabolism and prognosis, carbamoyl phosphate synthase 1 (CPS1) has been shown to be associated with poor prognosis in lung adenocarcinoma, and spermine synthase (SMS) has been reported to be associated with poor prognosis in hepatocellular carcinoma, head and neck squamous cell carcinoma, and colorectal cancer.