Dihydropyrimidine dehydrogenase enzyme, the key and rate-limiting enzyme for the catabolism of 5-fluorouracil (5-FU), is closely related to 5-FU clinical therapy.

• 双氢嘧啶脱氢酶（DPD酶）是5-氟尿嘧啶(5-FU)分解代谢的最主要的限速酶，与5-FU的临床疗效密切相关。