<prompt> Mechanism of action of paclitaxel is :Topoisomerase inhibitionIncreases the polymerization of tubulinInhibits protein synthesisAlkylation of DNA  <response>: 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. 