SLC31A1 and lung adenocarcinoma: 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).