Standing the test of time: targeting thymidylate biosynthesis in cancer therapy

Nat Rev Clin Oncol. 2014 May;11(5):282-98. doi: 10.1038/nrclinonc.2014.51. Epub 2014 Apr 15.


Over the past 60 years, chemotherapeutic agents that target thymidylate biosynthesis and the enzyme thymidylate synthase (TS) have remained among the most-successful drugs used in the treatment of cancer. Fluoropyrimidines, such as 5-fluorouracil and capecitabine, and antifolates, such as methotrexate and pemetrexed, induce a state of thymidylate deficiency and imbalances in the nucleotide pool that impair DNA replication and repair. TS-targeted agents are used to treat numerous solid and haematological malignancies, either alone or as foundational therapeutics in combination treatment regimens. We overview the pivotal discoveries that led to the rational development of thymidylate biosynthesis as a chemotherapeutic target, and highlight the crucial contribution of these advances to driving and accelerating drug development in the earliest era of cancer chemotherapy. The function of TS as well as the mechanisms and consequences of inhibition of this enzyme by structurally diverse classes of drugs with distinct mechanisms of action are also discussed. In addition, breakthroughs relating to TS-targeted therapies that transformed the clinical landscape in some of the most-difficult-to-treat cancers, such as pancreatic, colorectal and non-small-cell lung cancer, are highlighted. Finally, new therapeutic agents and novel mechanism-based strategies that promise to further exploit the vulnerabilities and target resistance mechanisms within the thymidylate biosynthesis pathway are reviewed.

Publication types

  • Review

MeSH terms

  • Antimetabolites, Antineoplastic / pharmacology*
  • Antimetabolites, Antineoplastic / therapeutic use
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • DNA Repair / drug effects
  • DNA Replication / drug effects
  • DNA, Neoplasm / biosynthesis
  • Drug Design
  • Drug Resistance, Neoplasm
  • Folic Acid Antagonists / pharmacology
  • Folic Acid Antagonists / therapeutic use
  • Humans
  • Models, Biological
  • Neoplasm Proteins / antagonists & inhibitors*
  • Neoplasm Proteins / physiology
  • Neoplasms / drug therapy*
  • Neoplasms / enzymology
  • Prodrugs / pharmacokinetics
  • Pyrimidines / pharmacology
  • Pyrimidines / therapeutic use
  • Thymidine Monophosphate / biosynthesis*
  • Thymidylate Synthase / antagonists & inhibitors*
  • Thymidylate Synthase / physiology


  • Antimetabolites, Antineoplastic
  • DNA, Neoplasm
  • Folic Acid Antagonists
  • Neoplasm Proteins
  • Prodrugs
  • Pyrimidines
  • Thymidine Monophosphate
  • Thymidylate Synthase