In contrast, decreased SLC31A1 mRNA expression levels were observed in cholangiocarcinoma (CHOL), kidney chromophobe (KIRC), kidney renal clear cell carcinoma (KIRP), liver hepatocellular carcinoma (LIHC), lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), prostate adenocarcinoma (PRAD), thyroid carcinoma (THCA) tumor tissues (P < 0.001). Here, SLC31A1 is linked to squamous cell lung carcinoma.