Cross-resistance to the lipid-soluble antifolate trimetrexate in human carcinoma cells with the multidrug-resistant phenotype.

@article{Assaraf1989CrossresistanceTT,
  title={Cross-resistance to the lipid-soluble antifolate trimetrexate in human carcinoma cells with the multidrug-resistant phenotype.},
  author={Yehuda G. Assaraf and Andrea Molina and Robert T. Schimke},
  journal={Journal of the National Cancer Institute},
  year={1989},
  volume={81 4},
  pages={
          290-4
        }
}
We are studying mechanisms of resistance to hydrophilic and lipophilic antifolates in cultured mammalian cells. We determined the cytotoxicity of methotrexate and the lipid-soluble antifolate trimetrexate to various human carcinoma cells and their doxorubicin-resistant sublines. These multidrug-resistant cells were 17-fold to 26-fold more resistant to trimetrexate but as sensitive to methotrexate as their parental cells. Verapamil and quinidine, which are known to modulate the degree of… 
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