A comparison of melphalan transport in human breast cancer cells and lymphocytes in vitro.
Evidence is presented that melphalan uptake by MCF-7 human breast cancer cells and peripheral blood lymphocytes from normal human subjects is an active process involving 2 amino acid carriers. Quantitative differences were observed in drug transport between the 2 cell types. Cell/medium distribution ratios of melphalan at equilibrium conditions were approx. 4-fold higher in breast cancer cells than in lymphocytes. The transport capacity, Vmax, for both carrier systems was at least 50-fold greater in MCF-7 cells than in lymphocytes, whereas the Michaelis constants were similar. These findings, in part, provide a rational basis for the use of melphalan in the chemotherapy of breast cancer.
D000596:Amino Acids / Q000378:metabolism; D001692:Biological Transport; D001943:Breast Neoplasms / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism; D002478:Cells, Cultured; D004347:Drug Interactions; D007700:Kinetics; D008214:Lymphocytes / Q000378:metabolism*; D008558:Melphalan / Q000097:blood / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism
D000596:Amino Acids; D002352:Carrier Proteins; D012964:Sodium; D008558:Melphalan