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Updated: Jul 3, 2026
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Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
Published on: February 9, 2021
Thymidylate synthase inhibitory drugs induce p53-dependent pathways differently
Eszter Holub1,2,3, Milda Blanka Szajkó1,2, Anna Felföldi1
1Department of Applied Biotechnology and Food Science, Faculty of Chemical Technology and Biotechnology at Budapest University of Technology and Economics, Budapest, Hungary.
Plos One
|July 1, 2026
Summary
Thymidylate synthase (TS) inhibition disrupts DNA synthesis and triggers cell death. Beyond its enzymatic role, TS interacts with RNA, influencing gene expression and revealing drug-specific cellular responses.
Area of Science:
- Biochemistry
- Molecular Biology
- Cancer Therapeutics
Background:
- Thymidylate synthase (TS) is crucial for DNA synthesis and a target for chemotherapy.
- TS inhibition causes DNA damage and cell death by disrupting nucleotide balance.
- TS also interacts with RNA, suggesting roles beyond its catalytic function.
Purpose of the Study:
- To investigate the transcriptomic effects of TS inhibition by 5-fluoro-2'-deoxyuridine (5FdUR) and raltitrexed (RTX).
- To explore the non-catalytic RNA-binding role of TS in cellular responses.
- To compare drug-specific transcriptional signatures and cellular responses.
Main Methods:
- Treatment of HCT116 cells with 5FdUR or RTX.
- Transcriptomic analysis (RNA sequencing).
- Quantitative PCR (qPCR) and Western blotting for validation.
- Co-immunoprecipitation coupled to sequencing to identify RNA partners.
Main Results:
- Both 5FdUR and RTX induced DNA damage responses but with distinct transcriptional profiles.
- A significant induction of p53-related gene expression was observed with 5FdUR treatment.
- Direct RNA binding partners of TS were identified, supporting its post-transcriptional regulatory role.
Conclusions:
- TS inhibition has multifaceted effects, impacting both DNA metabolism and RNA regulation.
- Distinct cellular responses are elicited by different TS inhibitors, such as 5FdUR and RTX.
- TS's interaction with RNA highlights its broader role in gene regulation beyond DNA synthesis.
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