Inducible expression of human lung cancer-related mutant EGFR genes in transgenic mice caused the development of lung adenocarcinoma, whereas stopping inducible expression of the mutant EGFR genes led to lung tumor regression [191,192], demonstrating that activating EGFR mutations are required and sufficient for lung cancer tumorigenesis and malignancy maintenance. The gene discussed is EGFR; the disease is lung cancer.