Aurora A kinase inhibition compromises its antitumor efficacy by elevating PD-L1 expression

Area of Science:

• Oncology
• Immunology
• Molecular Biology

Background:

• Aurora A kinase is crucial for cell division and a target in cancer therapy.
• Aurora A inhibitors show promise preclinically but have limited clinical success.
• The mechanism behind limited clinical efficacy requires further investigation.

Purpose of the Study:

• To investigate the immunomodulatory effects of Aurora A inhibitors.
• To elucidate the mechanism by which Aurora A affects anti-tumor immunity.
• To explore combination strategies to enhance the efficacy of Aurora A inhibitors.

Main Methods:

• Treatment of tumor cells and immune-competent mice with alisertib, an Aurora A inhibitor.
• Analysis of programmed death ligand 1 (PD-L1) expression.
• Investigation of the cGAS/STING/NF-κB pathway activation.
• Combination therapy with anti-PD-L1 antibody.

Main Results:

• Alisertib upregulated PD-L1 expression in tumor cells, suppressing anti-tumor immunity.
• Aurora A directly phosphorylates cGAS, inhibiting PD-L1 expression.
• Alisertib treatment activates the cGAS/STING/NF-κB pathway, leading to increased PD-L1.
• Combination of alisertib and anti-PD-L1 antibody enhanced anti-tumor effects in mice.

Conclusions:

• Aurora A inhibitors can paradoxically enhance PD-L1 expression, reducing anti-tumor immunity.
• The cGAS-STING pathway is involved in mediating the effects of Aurora A on PD-L1.
• Combining Aurora A inhibitors with PD-L1 blockade represents a promising strategy to improve cancer treatment efficacy.