Targeting replication stress response using polypurine reverse hoogsteen hairpins directed against WEE1 and CHK1

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Eva Aubets1, Véronique Noé1, Carlos J Ciudad1

  • 1Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences and Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona (UB), 08028 Barcelona, Spain.

Biochemical Pharmacology
|March 17, 2020
PubMed

Insights

Polypurine Reverse Hoogsteen hairpins (PPRHs) effectively silenced WEE1 and CHK1 genes, crucial for cancer cell survival. This inhibition reduced cancer cell viability and enhanced apoptosis, showing promise as an anticancer strategy.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Gene Silencing

Background:

  • Cell cycle checkpoints are vital for repairing DNA damage and maintaining genomic integrity.
  • Cancer cells, with high replication rates and genetic instability, rely on the replication stress response (RSR).
  • Inhibiting RSR pathways presents a potential anticancer therapeutic strategy.

Purpose of the Study:

  • To investigate the efficacy of Polypurine Reverse Hoogsteen hairpins (PPRHs) in silencing WEE1 and CHK1, key RSR components.
  • To evaluate PPRHs as a potential gene-silencing tool for cancer therapy.
  • To assess the synergistic effects of PPRHs with existing chemotherapeutic agents.

Main Methods:

  • Designing and utilizing PPRHs to target WEE1 and CHK1 genes for silencing.
  • Assessing the impact of PPRHs on cancer cell viability, apoptosis, and cell cycle progression in vitro.
  • Quantifying changes in WEE1 and CHK1 mRNA and protein levels post-PPRH treatment.
  • Evaluating the combined effects of PPRHs with DNA damaging agents like methotrexate and 5-Fluorouracil.

Main Results:

  • PPRHs targeting WEE1 or CHK1 significantly reduced the viability of various cancer cell lines.
  • Apoptosis increased in HeLa cells treated with PPRHs.
  • PPRH treatment led to dose- and time-dependent reductions in WEE1 and CHK1 mRNA and protein levels.
  • PPRHs disrupted the cell cycle and demonstrated synergistic effects when combined with methotrexate or 5-Fluorouracil.

Conclusions:

  • PPRHs are validated as an effective in vitro gene-silencing tool against RSR genes WEE1 and CHK1.
  • Inhibiting WEE1 and CHK1 holds potential as a monotherapy or combination therapy for cancer treatment.
  • PPRHs show promise for enhancing the efficacy of conventional chemotherapy agents.
Keywords:
CHK1Cell cycle checkpointDNA damagePPRHReplication stressWEE1

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