Question

Drugs vincristine and vinblastine used in cancer therapy are obtained
a. Rauwolfia serpentina
b. Atropa belladonna
c. Catharanthus roseus
d. Withania somnifera

Answer 1

Hint: Vinblastine and vincristine are the plant alkaloids used for clinical purposes. These are extracted from asymmetric dimeric compounds obtained from periwinkle plants.

Complete answer:
Vinblastine and vincristine are the vinca alkaloids used as chemotherapy drugs for treatment of cancer. These are obtained from Catharanthus roseus which is commonly known as periwinkle plant. It is a small perennial flowering plant that belongs to the family Apocynaceae. These plants are native to Madagascar Island. These are also used as an ornamental plant because of their pink/white flowers which are their source of their attraction.

These drugs, vinblastine and vincristine are known to prevent further division of cancer cells thereby preventing the cancerous growth. These drugs bind to the ends of microtubules thus inducing microtubule depolymerization. This leads to inhibition of mitotic progression hence promoting the cell death. Moreover, these drugs are lipid-soluble compounds.

On the other hand, Rauwolfia serpentina is used for treating hypertension. Atropa belladonna produces tropane alkaloids, namely hyoscyamine and scopolamine for treating inflammatory bowel disease, Parkinson's disease, motion sickness, colic and as a sedative. While Withania somnifera is itself used as a drug for treating various medical issues.

Hence, the correct answer is option (C).

Note: The drug vinblastine drug is primarily used for treatment of non-Hodgkin's lymphoma, Hodgkin lymphoma, bladder cancers, testicular, soft tissue sarcoma, Kaposi's sarcoma, t-cell lymphoma, bladder cancers and choriocarcinoma. Furthermore, Vincristine is used to treat head and neck cancers, breast cancer, leukaemia and various other forms of cancer.