Stephacidin B is a fungal metabolite that has been found in A. ochraceus.1 Dimeric stephacidin B is rapidly converted to a monomer, avrainvillamide , in vitro.2 Stephacidin B is cytotoxic to a variety of cancer cells, including testosterone-independent PC3 and -sensitive LNCaP prostate cancer cells (IC50s = 0.37 and 0.06 µM, respectively) and estradiol-independent SK-BR-3 and -sensitive MCF-7 breast cancer cells (IC50s = 0.32 and 0.27 µM, respectively).1 It induces apoptosis in HepG2 and Huh7 hepatocellular carcinoma cells when used at a concentration of 4 µM.3
1.Qian-Cutrone, J., Huang, S., Shu, Y.-Z., et al.Stephacidin A and B: Two structurally novel, selective inhibitors of the testosterone-dependent prostate LNCaP cellsJ. Am. Chem. Soc.124(49)14556-14557(2002) 2.Wulff, J.E., Herzon, S.B., Siegrist, R., et al.Evidence for the rapid conversion of stephacidin B into the electrophilic monomer avrainvillamide in cell cultureJ. Am. Chem. Soc.129(16)4898-4899(2007) 3.Hu, L., Zhang, T., Liu, D., et al.Notoamide-type alkaloid induced apoptosis and autophagy via a P38/JNK signaling pathway in hepatocellular carcinoma cellsRSC Adv.9(34)19855-19868(2019)