Create a biomedicine article inspired by the provided title: Resistance to methotrexate in thymidylate synthetase-deficient mutants of cultured mouse mammary tumor FM3A cells.
Output: Growth inhibition by methotrexate (MTX) of a cultured mouse mammary carcinoma FM3A line and its mutants deficient in thymidine kinase and thymidylate synthetase was studied under a variety of conditions. In medium containing 10 microM thymidine, the thymidylate synthetase-deficient mutants were slightly more resistant to MTX than the wild-type line and the thymidine kinase-deficient mutant. The addition of both 10 microM thymidine and 50 microM hypoxanthine to the medium completely eliminated the inhibition by MTX of the wild-type and thymidylate synthetase-deficient mutants but had no effect on inhibition of the thymidine kinase-deficient mutant. Thus, addition of either thymidine or purine alone was not sufficient to protect FM3A cells against the growth inhibitory effect of MTX. In contrast, addition of a small amount of 5-methyltetrahydrofolate to medium containing 10 microM thymidine caused an increase of several orders of magnitude in the resistance of thymidylate synthetase-deficient mutants to MTX but did not affect that of the wild-type line. Wild-type cells became almost as resistant to MTX as did the mutant cells by addition of 1 microM 5-fluorodeoxyuridine as well as a small amount of 5-methyltetrahydrofolate with thymidine. These results show directly that thymidylate synthetase is essential in determining the cytotoxicity of MTX by modulating the intracellular tetrahydrofolate pool.
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Based on the cause: "The addition of both 10 microM thymidine and 50 microM hypoxanthine to the medium completely eliminated the inhibition by MTX of the wild-type and thymidylate synthetase-deficient mutants but had no effect on inhibition of the thymidine kinase-deficient mutant."
What is likely to be the effect? Addition of either thymidine or purine alone was not sufficient to protect FM3A cells against the growth inhibitory effect of MTX.

The addition of both 10 microM thymidine and 50 microM hypoxanthine to the medium completely eliminated the inhibition by MTX of the wild-type and thymidylate synthetase-deficient mutants but had no effect on inhibition of the thymidine kinase-deficient mutant.
Produce a sentence that encompasses the concept from the above statement. Sentence: Addition of either thymidine or purine alone was not sufficient to protect FM3A cells against the growth inhibitory effect of MTX.

Can you generate a sentence that has a conflicting meaning compared to "Thus, addition of either thymidine or purine alone was not sufficient to protect FM3A cells against the growth inhibitory effect of MTX."? Addition of a small amount of 5-methyltetrahydrofolate to medium containing 10 microM thymidine caused an increase of several orders of magnitude in the resistance of thymidylate synthetase-deficient mutants to MTX but did not affect that of the wild-type line.

Generate a biomedicine sentence about: thymidylate, hypoxanthine, synthetase
Sentence: The addition of both 10 microM thymidine and 50 microM hypoxanthine to the medium completely eliminated the inhibition by MTX of the wild-type and thymidylate synthetase-deficient mutants but had no effect on inhibition of the thymidine kinase-deficient mutant.

Generate a biomedicine sentence about: synthetase, inhibition, methotrexate
Sentence: Growth inhibition by methotrexate (MTX) of a cultured mouse mammary carcinoma FM3A line and its mutants deficient in thymidine kinase and thymidylate synthetase was studied under a variety of conditions.