El-Readi et al. investigated the P-gp reversal activities of 1 and deacetylnomilin (4), isolated from C. jambhiri and C. pyriformis in human leukemia cells (CEM/ADR5000), and also their potential cytotoxicity against this cell line, as well as its parental cell line CCRF-CEM (Adriamycin-sensitive human leukemia cell line, no expression of P-gp) and Caco-2 cells [51]. The gene discussed is PGP; the disease is leukemia.