Mechanism of action of paclitaxel is :: (A) Topoisomerase inhibition, (B) Increases the polymerization of tubulin, (C) Inhibits protein synthesis, (D) Alkylation of DNA
Answer is B. Taxanes (paclitaxel and docetaxel) act by increasing the polymerization of tubulin whereas vinca alkaloids (vincristine, vinblastine and vinorelbine) cause inhibition of tubulin polymerization. Both of these drugs act by causing the disruption of mitosis and are active in M-phase of the cell cycle.