Eniluracil Treatment Completely Inactivates Dihydropyrimidine Dehydrogenase in Colorectal Tumors

Abstract

This study provides definitive evidence that eniluracil completely inactivates DPD activity in human solid tumors. The increased plasma uracil and decreased DPD activity are consistent with systemic inactivation of the enzyme. The mechanism of inactivation is at the catalytic level, because no changes in DPD protein or mRNA were observed. Treatment with eniluracil will eliminate DPD activity as a source of pharmacokinetic fluorouracil variability or resistance in human colorectal cancer.