MDR gene is a p-glycorprotein, an energy-dependent pump that serves to remove exogenous toxins or endogenous metabolites from the cell. It is found in a wide range of normal tissues. That includes: adrenal tissue, cells lining the renal tubule, cells lining the jejunum and colon, cells lining the bile canaliculi, & endothelial cells of capillaries in the brain and testes.
CHEMOTHERAPY AGENTS NOT AFFECTED BY MDR:
CHEMOTHERAPY AGENTS THAT ARE AFFECTED BY MDR:
2. Vinca Alkaloids
How to overcome MDR-1?mediated drug resistance?
Many agents directly inhibit the P-glycoprotein pump: amphotericin B, colchicine, diltiazem, cyclosporine, erythromycin, hormones, verapamil, & VX-170.