This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti-Cancer, Subject name: Pharmacology
[{'content': 'Cell cycle specific anti-cancerous drug is? \nSelect and explain. \nA. Cyclophosphamide, B. Vincristine, C. Nitrogen mustard, D. Doxorubicin.', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. b (Vincristine). (Ref. Harrison Principles of Internal Medicine, 16th ed., 469 Fig. 70.3)CYCLE SPECIFIC ANTICANCEROUS DRUGSS-Phase specific drugsM-Phase specific drugsG,Phase specific drugsHydroxyurea,Methotrexate,Dactinomycin,Cytarabine,5-FU,MercaptopurineThiogauanine,ColchicinesVinca alkaloids and taxols (e.g., vincristine, vinblastine, paclitaxel).Vinca alkaloids (vincristine, vinblastine) inhibit mitotic spindle formation while taxels (paclitaxel) stabilize the mitotic spindles. Thus are known as'Spindle poisons'.Intercalaters: Anthracyclines and actinomycin D.By crosslinking between adjacent guanine in DNA: Cisplatin.By DNA breakage: Bleomycin.", 'role': 'assistant'}]