5-Nitrouracil stabilizes the plasma concentration values of 5-FU in colorectal cancer patients receiving capecitabine.
Sci Rep
; 10(1): 2711, 2020 02 17.
Article
in En
| MEDLINE
| ID: mdl-32066801
Capecitabine is selectively converted from 5'-DFUR to 5-fluorouracil (5-FU) in tumours by thymidine phosphorylase (TP). We investigated the addition of 5-nitrouracil (5-NU), a TP inhibitor, into blood samples for precise measurements of plasma 5-FU concentrations. The plasma concentration of 5-FU was measured after capecitabine administration. Two samples were obtained at 1 or 2 h after capecitabine administration and 5-NU was added to one of each pair. Samples were stored at room temperature or 4 °C and 5-FU concentrations were measured immediately or 1.5 or 3 h later. The mean plasma 5-FU concentration was significantly higher at room temperature than at 4 °C (p < 0.001). The 5-FU concentration was significantly increased in the absence of 5-NU than in the presence of 5-NU (p < 0.001). The 5-FU change in concentration was greater in the absence of 5-NU, and reached 190% of the maximum compared with baseline. A significant interaction was found between temperature and 5-NU conditions (p < 0.001). Differences between the presence or absence of 5-NU were greater at room temperature than under refrigerated conditions. 5-FU plasma concentrations after capecitabine administration varied with time, temperature, and the presence or absence of 5-NU. This indicates that plasma concentrations of 5-FU change dependent on storage conditions after blood collection.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Thymidine Phosphorylase
/
Uracil
/
Colorectal Neoplasms
/
Capecitabine
/
Fluorouracil
/
Antimetabolites, Antineoplastic
Limits:
Adult
/
Female
/
Humans
/
Male
Language:
En
Journal:
Sci Rep
Year:
2020
Document type:
Article
Affiliation country:
Japan
Country of publication:
United kingdom