[Membrane transport of antineoplastic drugs and its relevance to tumour chemotherapy (author's transl)].

The permeation of cell membranes by several antineoplastic drugs (AD) exhibits characteristics of carrier-mediated transport processes (facilitated diffusion or active transport); the main representatives among these AD are mechlorethamine, cyclophosphamide, melphalan, methotrexate, 6-mercaptopurine, 5-fluorouracil, cytarabine, 5-fluorodeoxyuridine, vincristine, vinblastine, adriamycin, daunorubicin and dactinomycin. Inhibition or stimulation of the membrane transport of AD influences absorption, distribution, elimination, therapeutic effectiveness and toxicity. The choice of certain combination therapies may increase the selectivity of AD by influencing membrane transport. A change in the properties of transport systems is one possible reason for the resistance of tumour cells to various AD.