Accordingly, it induced an arrest in the G1 phase of cell cycle in human lung cancer cells, which was mediated by a downregulation of cyclins D1 and E, cyclin-dependent protein kinase (CDK)-2, -4, and -6, and by the upregulation of G1 cell cycle negative regulators (i.e., p21CIP1/WAF1 and p27KIP1); also, lowered levels of phosphorylated retinoblastoma (p-RB) protein by the sesquiterpenes were found [153]. The gene discussed is CDKN1A; the disease is lung cancer.