First isolated in 1995 by Osada and colleagues from Aspergillus fumigatus BM939, these natural products arenotable for their ability to inhibit the cell cycle of mouse tsFT210cells, with minimum inhibitory concentrations (MICs) of 16.4 μMfor TPS A and 4.4 μM for TPS B. TPSA primarily induces G2/M phase cell cycle arrest by inhibiting tubulinpolymerization. and has shown potentialin reversing drug resistance by targeting the breast cancer resistanceprotein (BCRP/ABCG2). While TPS B exhibitsgreater potency than TPS A, its cytotoxicity is not restricted tothe M phase. Here, ABCG2 is linked to cancer.