EGFR and head and neck squamous cell carcinoma: According to the TIMER database, EGFR was upregulated in five cancers, including GBM, head and neck squamous cell carcinoma, kidney renal cell carcinoma, kidney renal cell papillary cell carcinoma, and lung squamous cell carcinoma, whereas it was downregulated in breast invasive carcinoma, colon adenocarcinoma, pheochromocytoma and paraganglioma, prostate adenocarcinoma, rectum adenocarcinoma, and uterine corpus endometrial carcinoma.