Cirsiliol is a flavonoid that has been found in S. indicum and has diverse biological activities.1 It inhibits 5-lipoxygenase (5-LO) and 12-LO (IC50s = 0.1 and 1 ?M, respectively).1 Cirsiliol inhibits the release of slow-reacting substance of anaphylaxis (SRS-A) in passively sensitized isolated guinea pig lung (IC50 = 0.4 ?M). It induces relaxation of precontracted isolated rat uterus, urinary bladder, proximal aorta, and trachea in a concentration-dependent manner.2 Cirsiliol inhibits colony formation and migration of B16/F10 murine melanoma cells.3 In vivo, cirsiliol (200 ?g/kg) enhances radiation-induced inhibition of tumor growth in an H1299 non-small cell lung cancer (NSCLC) mouse xenograft model.4
1.Yoshimoto, T., Furukawa, M., Yamamoto, S., et al.Flavonoids: Potent inhibitors of arachidonate 5-lipoxygenaseBiochem. Biophys. Res. Commun.116(2)612-618(1983) 2.Mustafa, E.H., Zarga, M.A., Sabri, S., et al.Effects of cirsiliol, a flavone isolated from Achillea fragrantissima, on rat isolated smooth muscleInt. J. Pharm.33(3)204-209(1995) 3.Prasad, P., Vasas, A., Hohmann, J., et al.Cirsiliol suppressed epithelial to mesenchymal transition in B16F10 malignant melanoma cells through alteration of the PI3K/Akt/NF-κB signaling pathwayInt. J. Mol. Sci.20(3)608(2019) 4.Kang, J., Kim, E., Kim, W., et al.Rhamnetin and cirsiliol induce radiosensitization and inhibition of epithelial-mesenchymal transition (EMT) by miR-34a-mediated suppression of Notch-1 expression in non-small cell lung cancer cell linesJ. Biol. Chem.288(38)27343-27357(2013)