Exposure of HCT116 and SW480 colorectal cancer cells to patchouli alcohol activated p21 expression and inhibited the expression of cyclin D1 and CDK4 and induced cell apoptosis and cell cycle arrest in A549 lung cancer cells in vitro and in vivo via the EGFR-MAPK pathway [39, 40]. The gene discussed is EGFR; the disease is lung carcinoma.