Taccalonolide A

Taccalonolide A is the first microtubule stabilizing agent to be discovered from a plant since identification of the mechanism of action of paclitaxel and it is the first natural product steroid identified to have these cellular effects, with cytotoxic and antimalarial activities. Taccalonolide A causes G2-M accumulation, Bcl-2 phosphorylation and initiation of apoptosis. Taccalonolide A is effective in vitro against cell lines that overexpress P-glycoprotein (Pgp) and multidrug resistance protein 7 (MRP7), with an IC50 of 622 nM for SK-OV-3 cells.

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