Wortmannin, 10 mg

A small-molecule research compound from STEMCELL Technologies, wortmannin is a fungal metabolite that covalently binds to and inhibits phosphatidylinositol 3-kinases (PI3K) of class I, II, and III. Species-specific differences in the class II PI3Ks determine sensitivity, with IC₅₀ values of 5 nM (Drosophila), 50 nM (mouse), and 450 nM (human). The compound also inhibits polo-like kinases PLK1 and PLK3, with reported IC₅₀ values of 24 nM and 49 nM, respectively. At higher concentrations it can additionally affect mammalian target of rapamycin (mTOR), DNA-dependent protein kinase catalytic subunit (DNA-PKcs), phosphatidylinositol 4-kinase (PI4K), myosin light-chain kinase (MLCK), and mitogen-activated protein kinase (MAPK).

The molecule has the chemical formula C₂₃H₂₄O₈, a molecular weight of 428.4 g/mol, and a CAS number of 19545-26-7. It is supplied as a crystalline solid with a stated purity of ≥ 98%. The compound is soluble in DMSO at ≤ 30 mM and in absolute ethanol at ≤ 0.3 mM, but has low solubility in aqueous media. To prepare a 10 mM stock in DMSO, 1 mg should be resuspended in 233 µL of DMSO, with stocks prepared fresh before use and stored at -20°C. Working aliquots are recommended to avoid repeated freeze-thaw cycles, and final DMSO concentration in cell culture should be kept below 0.1% due to potential cell toxicity. The product is stable at -20°C as supplied and should be protected from prolonged exposure to light. This product is hazardous; users are referred to the Safety Data Sheet (SDS).

Wortmannin is described as an inhibitor of the PI3K/AKT pathway with downstream effects on PLK signaling. Published applications include cancer research, where it exhibits cytotoxic activity on a number of human tumor cell lines in vitro and shows anti-tumor activity in mouse xenografts of C3H mammary carcinoma and BxPC-3 pancreatic carcinoma cells.