Skip to main content
Advertisement

Main menu

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET

User menu

  • My alerts
  • Log in
  • My Cart

Search

  • Advanced search
Drug Metabolism & Disposition
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET
  • My alerts
  • Log in
  • My Cart
Drug Metabolism & Disposition

Advanced Search

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Visit dmd on Facebook
  • Follow dmd on Twitter
  • Follow ASPET on LinkedIn
Research ArticleArticle

IDENTIFICATION OF THE CYTOSOLIC CARBOXYLESTERASE CATALYZING THE 5′-DEOXY-5-FLUOROCYTIDINE FORMATION FROM CAPECITABINE IN HUMAN LIVER

Toshiki Tabata, Miki Katoh, Shogo Tokudome, Miki Nakajima and Tsuyoshi Yokoi
Drug Metabolism and Disposition October 2004, 32 (10) 1103-1110; DOI: https://doi.org/10.1124/dmd.104.000554
Toshiki Tabata
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Miki Katoh
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Shogo Tokudome
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Miki Nakajima
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Tsuyoshi Yokoi
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF
Loading

Abstract

Capecitabine, a prodrug of 5-fluorouracil, is first metabolized to 5′-deoxy-5-fluorocytidine (5′-DFCR) by carboxylesterase (CES), which is mainly expressed in microsomes. Recently, we clarified that 5′-DFCR formation was catalyzed by the enzyme in cytosol as well as microsomes in human liver. In the present study, the cytosolic enzyme involved in 5′-DFCR formation from capecitabine was identified. This enzyme was purified in the cytosolic preparation by ammonium sulfate precipitation, Sephacryl S-300 gel filtration, Mono P chromatofocusing, and Superdex 200 gel filtration. The purified enzyme was identified by the amino acid sequence analysis to be CES1A1 or a CES1A1 precursor. Based on the result of the N-terminal amino acid sequence analysis, the purified enzyme has no putative signal peptide, indicating that it was CES1A1. The apparent Km and Vmax values of 5′-DFCR formation were 19.2 mM and 88.3 nmol/min/mg protein, respectively. The 5′-DFCR formation catalyzed by the purified enzyme was inhibited by both diisopropylfluorophosphate and bis(p-nitrophenyl)phosphate in a concentration-dependent manner. 7-Ethyl-10-hydroxycamptothecin (SN-38) formation from irinotecan also occurred in the purified enzyme, cytosol, and microsomes. In conclusion, the cytosolic enzyme involved in 5′-DFCR formation from capecitabine would be CES1A1. It is suggested that the cytosolic CES has significant hydrolysis activity and plays an important role as the microsomal CES in drug metabolism. It is worthy to investigate the metabolic enzyme in cytosol involved in the activation of ester-type prodrugs such as capecitabine.

Footnotes

  • This study was supported by a grant-in-aid for Encouragement of Young Scientists of the Ministry of Education, Culture, Sports, Science and Technology of Japan.

  • doi:10.1124/dmd.104.000554.

  • ABBREVIATIONS: 5-FU, 5-fluorouracil; 5′-DFCR, 5′-deoxy-5-fluorocytidine; CES, carboxylesterase; 5′-DFUR, 5′-deoxy-5-fluorouridine (doxifluridine); CDA, cytidine deaminase; TP, thymidine phosphorylase; CDHP, 5-chloro-2,4-dihydroxypyridine; TPI, 5-chloro-6-(2-iminopyrrolidin-1-yl)methyl-2,4-(1H,3H)-pyrimidinedione; DFP, diisopropylfluorophosphate; BNPP, bis(p-nitrophenyl)phosphate; THU, tetrahydrouridine; CPT-11, irinotecan hydrochloride trihydrate; SN-38, 7-ethyl-10-hydroxycamptothecin; PAGE, polyacrylamide gel electrophoresis; TFA, trifluoroacetic acid; HPLC, high-performance liquid chromatography.

    • Received May 8, 2004.
    • Accepted July 12, 2004.
  • The American Society for Pharmacology and Experimental Therapeutics
View Full Text

 

DMD articles become freely available 12 months after publication, and remain freely available for 5 years. 

Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page. 

 

  • Click here for information on institutional subscriptions.
  • Click here for information on individual ASPET membership.

 

Log in using your username and password

Forgot your user name or password?

Purchase access

You may purchase access to this article. This will require you to create an account if you don't already have one.
PreviousNext
Back to top

In this issue

Drug Metabolism and Disposition: 32 (10)
Drug Metabolism and Disposition
Vol. 32, Issue 10
1 Oct 2004
  • Table of Contents
  • About the Cover
  • Index by author
Download PDF
Article Alerts
Sign In to Email Alerts with your Email Address
Email Article

Thank you for sharing this Drug Metabolism & Disposition article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
IDENTIFICATION OF THE CYTOSOLIC CARBOXYLESTERASE CATALYZING THE 5′-DEOXY-5-FLUOROCYTIDINE FORMATION FROM CAPECITABINE IN HUMAN LIVER
(Your Name) has forwarded a page to you from Drug Metabolism & Disposition
(Your Name) thought you would be interested in this article in Drug Metabolism & Disposition.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Research ArticleArticle

IDENTIFICATION OF THE CYTOSOLIC CARBOXYLESTERASE CATALYZING THE 5′-DEOXY-5-FLUOROCYTIDINE FORMATION FROM CAPECITABINE IN HUMAN LIVER

Toshiki Tabata, Miki Katoh, Shogo Tokudome, Miki Nakajima and Tsuyoshi Yokoi
Drug Metabolism and Disposition October 1, 2004, 32 (10) 1103-1110; DOI: https://doi.org/10.1124/dmd.104.000554

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero

Share
Research ArticleArticle

IDENTIFICATION OF THE CYTOSOLIC CARBOXYLESTERASE CATALYZING THE 5′-DEOXY-5-FLUOROCYTIDINE FORMATION FROM CAPECITABINE IN HUMAN LIVER

Toshiki Tabata, Miki Katoh, Shogo Tokudome, Miki Nakajima and Tsuyoshi Yokoi
Drug Metabolism and Disposition October 1, 2004, 32 (10) 1103-1110; DOI: https://doi.org/10.1124/dmd.104.000554
Reddit logo Twitter logo Facebook logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • Abstract
    • Materials and Methods
    • Results
    • Discussion
    • Acknowledgments
    • Footnotes
    • References
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF

Related Articles

Cited By...

More in this TOC Section

  • Ontogeny of CPPGL
  • Expression of AKR and SDR Isoforms in the Human Intestine
  • Metabolism of Lufotrelvir in Humans
Show more Articles

Similar Articles

Advertisement
  • Home
  • Alerts
Facebook   Twitter   LinkedIn   RSS

Navigate

  • Current Issue
  • Fast Forward by date
  • Fast Forward by section
  • Latest Articles
  • Archive
  • Search for Articles
  • Feedback
  • ASPET

More Information

  • About DMD
  • Editorial Board
  • Instructions to Authors
  • Submit a Manuscript
  • Customized Alerts
  • RSS Feeds
  • Subscriptions
  • Permissions
  • Terms & Conditions of Use

ASPET's Other Journals

  • Journal of Pharmacology and Experimental Therapeutics
  • Molecular Pharmacology
  • Pharmacological Reviews
  • Pharmacology Research & Perspectives
ISSN 1521-009X (Online)

Copyright © 2023 by the American Society for Pharmacology and Experimental Therapeutics