Checkpoint Kinase 1 Inhibitor Combined with Low Dose Hydroxyurea Promotes ATM-Activated NF-κB-Dependent...

Area of Science:

• Oncology
• Immunology
• Molecular Biology

Background:

• Melanoma incidence is rising globally, with treatment resistance a common challenge.
• Novel therapeutic strategies are needed to overcome treatment resistance and enhance anti-tumour immune responses.

Purpose of the Study:

• To investigate the effect of SRA737 (checkpoint kinase 1 inhibitor) combined with low-dose hydroxyurea (LDHU) on melanoma cells.
• To elucidate the underlying molecular mechanisms of SRA737 + LDHU-induced anti-tumour effects, including chemokine and cytokine modulation.

Main Methods:

• Assessed chemokine and cytokine expression in human melanoma cell lines treated with SRA737 + LDHU.
• Investigated the regulatory pathways, including ATM and NF-κB signalling, involved in treatment-induced gene expression.

Main Results:

• SRA737 + LDHU treatment upregulated pro-inflammatory chemokines in melanoma cells via the ATM-NF-κB signalling pathway.
• Increased chemokine expression correlated with enhanced secretion, suggesting a modified tumour microenvironment.
• Inhibition of ATM or NF-κB did not impede SRA737 + LDHU-induced melanoma cell death.

Conclusions:

• SRA737 + LDHU effectively upregulates pro-inflammatory chemokine expression in melanoma.
• The ATM-NF-κB pathway is crucial for mediating this chemokine upregulation.
• These findings suggest a potential mechanism for enhancing anti-tumour immunity in melanoma.