H2AX: A key player in DNA damage response and a promising target for cancer therapy

Kirti S Prabhu1, Shilpa Kuttikrishnan1, Nuha Ahmad1

  • 1Translational Research Institute, Academic Health System, Hamad Medical Corporation, Doha 3050, Qatar.

Insights

DNA damage response involves histone variant H2AX (γH2AX) phosphorylation, crucial for genomic stability and cancer progression. Targeting H2AX offers therapeutic potential as a biomarker and treatment strategy.

Area of Science:

  • Molecular Biology
  • Genetics
  • Cancer Research

Background:

  • Cancer arises from disrupted cell growth and division, often linked to unrepaired DNA damage and genomic instability.
  • The DNA damage response (DDR) system, including histone variant H2AX phosphorylation (γH2AX), is vital for maintaining genomic integrity.
  • Unrepaired DNA damage can lead to mutations, driving cancer initiation and progression.

Purpose of the Study:

  • To explain the molecular dynamics of H2AX in DNA damage response.
  • To emphasize H2AX's role in recruiting repair machinery to damaged chromatin.
  • To explore the therapeutic potential of targeting H2AX in cancer treatment.

Main Methods:

  • Review of molecular dynamics of H2AX phosphorylation.
  • Explanation of signaling pathways involving ATM and ATR kinases.
  • Analysis of H2AX roles in cell cycle checkpoints and apoptosis.

Main Results:

  • H2AX phosphorylation, mediated by ATM/ATR, signals DNA damage, activating downstream pathways.
  • γH2AX is crucial for recruiting DNA repair complexes to double-strand break sites.
  • H2AX phosphorylation regulates cell fate decisions, promoting repair or apoptosis.

Conclusions:

  • H2AX phosphorylation is a critical regulatory point in DNA damage response, impacting cell survival.
  • H2AX serves as a biomarker for DNA integrity and a potential therapeutic target in oncology.
  • Targeting H2AX pathways may enhance cancer treatment efficacy by influencing apoptosis and cell cycle control.

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