Which of the following anticancer drugs kills dividing cells by binding beta-tubulin and stabilizing polymerized microtubules, thereby preventing their depolymerization?
- A Vincristine
- B Etoposide
- C Paclitaxel ✓
- D Colchicine
Correct answer: C. Paclitaxel
Explanation
Taxanes such as paclitaxel bind the beta-tubulin subunit of polymerized microtubules and stabilize them against depolymerization, so the mitotic spindle cannot function and cells arrest in mitosis. Vincristine and colchicine both bind tubulin at distinct sites but prevent polymerization, the opposite effect. Etoposide does not touch tubulin at all; it forms a complex with topoisomerase II and DNA that causes strand breaks.
Reference: Katzung's Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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