Effects of thiol compounds on methotrexate uptake by murine lymphocytes from thymus and thymic lymphosarcoma.

  title={Effects of thiol compounds on methotrexate uptake by murine lymphocytes from thymus and thymic lymphosarcoma.},
  author={D. Sołtysiak-Pawłuczuk and A. Naciaźek-Wieniawska and A. Danysz and A. Czarnomska},
  journal={Cancer letters},
  volume={65 3},
The characteristics of methotrexate (MTX) uptake and the effects of exogenous sulfhydryl compounds (i.e. reduced glutathione and cysteine) on MTX accumulation in thymocytes and thymic lymphosarcoma cells has been studied. Significant differences in the rate and the extent of MTX uptake between normal and neoplastic cells were demonstrated. MTX accumulation was found to be more efficient in thymic lymphosarcoma cells as compared with parental cells. In the cells examined, MTX uptake was not… Expand
Effect of 5-fluorouracil on methotrexate transport and cytotoxicity in HT29 colon adenocarcinoma cells.
The results of this study suggest that the increase in cellular GSH level as a result of 5FU pretreatment may play a role in the enhancement of MTX uptake and the cytotoxicity of both drugs in HT29 cells. Expand
Cellular aspects of folate and antifolate membrane transport.
The physiological role of reduced folate carriers and folate receptors in normal and neoplastic cells is described regarding changes in transport activity and connection of transport systems with resistance to antifolates and cancer development. Expand
Human galectin-1, -2, and -4 induce surface exposure of phosphatidylserine in activated human neutrophils but not in activated T cells.
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Factors controlling the concentrations of methotrexate in cultured hepatic cells.
The polyglutamate metabolites of methotrexate are as inhibitory to the target enzyme dihydrofolate reductase as is metotrexate and have a longer half-life within the cells and thus a greater potential for cytotoxicity. Expand
Membrane transport of methotrexate in human lymphoblastoid cells.
The elucidation of a second route of MTX transport at high dose concentrations in human neoplastic cells may explain the apparent efficacy of high-dose MTX in MTX-“resistant” tumors. Expand
Carrier-mediated transport of the folic acid analogue, methotrexate, in the L1210 leukemia cell.
It is indicated that methotrexate transport in the L1210 cell is carrier-mediated and uphill, and the implication of these findings with respect to the development of more effective folic acid antagonists is considered. Expand
Transport and metabolism of methotrexate in normal and resistant cultured rat hepatoma cells.
The results suggest that the cells become resistant as a result of a stable change in the transport system for MTX, but the mechanism of this process is not yet understood. Expand
Kinetic correlates of methotrexate transport and therapeutic responsiveness in murine tumors.
Steady-state levels of drug accumulation in vitro reflected influx and efflux rates and were consistently correlatable with therapeutic responsiveness, and there was no significant difference in the extent to which folate and reduced 5-substituted folate derivatives compete with methotrexate for uptake in cells from all five tumors. Expand
A methotrexate-resistant human breast cancer cell line with multiple defects, including diminished formation of methotrexate polyglutamates.
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Transport of methotrexate in L1210 cells. Mechanism for inhibition by p-chloromercuriphenylsulfonate and N-ethylmaleimide.
Methotrexate transport in L1210 cells is highly sensitive to inhibition by p-chloromercuriphenylsulfonate (CMPS) and, to a lesser extent, by N-ethylmaleimide, while complete inhibition was achieved at higher levels of these agents. Expand
Evidence for inherent differences in the system A carrier from normal and transformed liver tissue. Differential inactivation and substrate protection in membrane vesicles and reconstituted proteoliposomes.
The results support the hypothesis that there are inherent differences in the System A carriers that are present in normal and transformed liver tissue. Expand
Structural and functional properties of the folate transport protein from a methotrexate-resistant subline of Lactobacillus casei
Findings indicate that the mutant binding protein exists in a low-affinity form due to disulfide bridge formation between two homologous protein subunits and that cleavage of this bond by mercaptoethanol generates the high-Affinity state. Expand