PNPLA2 and head and neck squamous cell carcinoma: Pnpla2 was significantly upregulated (p < 0.05) in liver hepatocellular carcinoma (LIHC), prostate adenocarcinoma (PRAD), thyroid carcinoma (THCA), and cholangiocarcinoma (CHOL), while significantly downregulated (p < 0.05) in breast invasive carcinoma (BRCA), head and neck squamous cell carcinoma (HNSC), kidney chromophobe (KICH), lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC) and pheochromocytoma and paraganglioma (PCPG).