Paclitaxel CAS#33069-62-4

Paclitaxel is a diterpenoid monomer isolated from the bark of Taxus species. As a structurally complex secondary metabolite, it represents the only known therapeutic agent capable of both promoting microtubule polymerization and stabilizing the resultant microtubule structures. Isotopic labeling studies demonstrate that paclitaxel specifically binds to polymerized microtubules without interacting with free tubulin dimers.

Cellular exposure to paclitaxel induces massive intracellular microtubule accumulation, which disrupts multiple cellular processes – most notably arresting cell cycle progression at the mitotic phase, thereby inhibiting normal cell division. Clinical trials (Phase II-III) have established its primary efficacy against ovarian and breast carcinomas, with demonstrated activity against various malignancies including non-small cell lung cancer, colorectal carcinoma, melanoma, head and neck cancers, lymphomas, and gliomas.