Hem-Onc: Microtubule Inhibitors

Question 1

Vincristine: mech

Answer 1

M phase specific
Vinca alkaloid that binds beta-tubulin, inhibit its polymerization into microtubules, therby preventing mitotic spindle formation (M-phase arrest)

Question 2

Vincristine: uses

Answer 2

Solid tumors, leukemias, lymphomas

Question 3

Vincristine: tox

Answer 3

neurotoxicity (areflexia, peripheral neuritis), paralytic ileus

Question 4

Vinblastine: mech

Answer 4

M phase specific
Vinca alkaloid that binds beta-tubulin, inhibits its polymerization into microtubules, thereby preventing mitotic spindle formation (M-phase arrest)

Question 5

Vinblastine: uses

Answer 5

Solid tumors, leukemias, and lymphomas

Question 6

Vinblastine: tox

Answer 6

VinBLASTine BLASTS Bone marrow (suppression)

Question 7

Paclitaxel, other taxols: mech

Answer 7

CCS: G2 and M phase
Hyperstabilize polymerized microtubules in M phase so that mitotic spindle cannot break down (anaphase cannot occur)
“It is taxing to stay polymerized”

Question 8

Paclitaxel: uses

Answer 8

Ovarian and breast carcinomas

Question 9

Paclitaxel: tox

Answer 9

Myelosuppression, alopecia, hypersensitivity