LRIG1 and cutaneous squamous cell carcinoma: LRIG1 belongs to LRIG gene family and functions as a tumor suppressor, and its high expression is associated with an increased survival in various tumor types including breast cancer, ovarian cancer, uterine cervical cancer, cutaneous squamous cell carcinoma, nasopharyngeal, oropharyngeal cancer, non-small cell lung cancer and hepatocellular carcinoma [46, 47].