ATP-dependent transport of vinblastine in vesicles from human multidrug-resistant cells

Journal Article · Sun May 01 00:00:00 EDT 1988 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.85.10.3580· OSTI ID:5517837

Horio, M; Gottesman, M M; Pastan, I ^[1]

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1. National Institutes of Health, Bethesda, MD (USA)

Resistance of human cancer cells to multiple cytotoxic hydrophobic agents (multidrug resistance) is due to overexpression of the MDR1 gene, whose product is the plasma membrane P-glycoprotein. Plasma membrane vesicles partially purified from multidrug-resistant human KB carcinoma cells, but not from drug-sensitive cells, accumulate ({sup 3}H)vinblastine in an ATP-dependent manner. This transport is osmotically sensitive, with an apparent K{sub m} of 38 {mu}M for ATP and of {approx} 2 {mu}M for vinblastine. The nonhydrolyzable analog adenosine 5{prime}-({beta},{gamma}-imido)triphosphate does not substitute for ATP but is a competitive inhibitor of ATP for the transport process. Vanadate, and ATPase inhibitor, is a potent noncompetitive inhibitor of transport. These results indicate that hydrolysis of ATP is probably required for active transport vinblastine. Several other drugs to which multidrug-resistant cell lines are resistant inhibit transport, with relative potencies as follows: vincristine > actinomycin D > daunomycin > colchicine = puromycin. Verapamil and quinidine, which reverse the multidrug-resistance phenotype, are good inhibitors of the transport process. These results confirm that multidrug-resistant cells express an energy-dependent plasma membrane transporter for hydrophobic drugs, and establish a system for the detailed biochemical analysis of this transport process.

• OSTI ID: 5517837
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Vol. 85:10; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ATP-ASE
BIOCHEMICAL REACTION KINETICS
TRITIUM COMPOUNDS
MEMBRANE TRANSPORT
TUMOR CELLS
SENSITIVITY
VINBLASTINE
ATP
ENZYME INHIBITORS
GLUCOPROTEINS
MAN
VANADATES
ACID ANHYDRASES
ALKALOIDS
ANIMAL CELLS
ANIMALS
ANTIMITOTIC DRUGS
AROMATICS
AZAARENES
AZOLES
CARBOHYDRATES
DRUGS
ENZYMES
GLYCOPROTEINS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
HYDROLASES
INDOLES
KINETICS
MAMMALS
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PHOSPHOHYDROLASES
PRIMATES
PROTEINS
PYRROLES
REACTION KINETICS
SACCHARIDES
TRANSITION ELEMENT COMPOUNDS
VANADIUM COMPOUNDS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques