Resistance to anticancer drugs

Question 0

glycoprotein transporters can be blocked by what drug?

Answer 0

Verapamil - calcium channel blocker

Question 1

Resistance in Anticancer drugs moa?

Answer 1

1 change in sensitivity or lowering binding affinity of target enzymes or receptors.

2 decreased drug accumulation vis increased expression of glycoprotein transporter or via reduced permeabillity.

Question 2

Other moas of resistance to anticancer drugs are?

Answer 2

• formation of drug-inactivating enzymes
• production of reactive chemicals that “trap” the anticancer drug
• increased nucleic acid repair mecanisms
• reduced activation of prodrugs

Question 3

What is primary resistance?

Answer 3

drug do not respond to initial therapy. Related to the frequency of spontaneous mutations(105 - 109) = increased probability of resistance

Question 4

What is aquired resistance?

Answer 4

Resistance that develops or appear during therapy. May occur due to:

1 Amplification of target genes(dihydrofolate reductase - methotrexate)

2 Multidrug resistance = increased gp transporters

Question 5

Name three pharmacologic sanctuaries

Answer 5

1 brain
2 testes
3 ovaries

Question 6

Inhibitors of microtubule function

Answer 6

Vinca alkaloids and Paclitaxel

Question 7

Ribonucleotide reductase inhibitor =

Answer 7

hydroxyurea

Question 8

dTMP synthesis inhibitors are …..

Answer 8

Methotrexate and 5-Fluorouracil