曲霉素鈉產品是Fostriecin is a potent inhibitor of the serine/threonine protein phosphatases PP2A and PP4 with IC?? value of 3.2 and 3 nM, respectively. It also displays weak inhibition of topoisomerase II having IC?? of 40 μM and PP1 with IC?? of 131 μM. Fostriecin has antitumor activity against a wide spectrum of tumor cells?in vitro?and excellent activity against P388 and L1210 leukemias?in vivo.