KROK 1 2009 – Question 195 · KROK (Medicine) · Biological Chemistry
An oncological patient was administered methotrexate. With the lapse of time the target cells of the tumour lost sensitivity to this preparation. We can observe changes in the gene expression of the following enzyme:
- A. Folate decarboxylase
- B. Dihydrofolate reductase
- C. Thiminase
- D. Folate oxidase
- E. Desaminase
Hint
Ask which enzyme is the direct pharmacological target of this antimetabolite and how a rise in the amount of that enzyme could blunt the drug's effect.
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