SLC31A1 and head and neck squamous cell carcinoma: Upregulation of SLC31A1 is associated with poor OS in cervical squamous cell carcinoma, esophageal cancer, BRCA, or head and neck squamous cell carcinoma patients.365 The analysis of tumor immune infiltration revealed associations between the expression of SLC31A1 and the presence of T cells, and macrophages within the TME.