Blocking PD1/PDL1 Interactions Together with MLN4924 Therapy is a Potential Strategy for Glioma Treatment

Area of Science:

• Neuro-oncology
• Cancer immunology
• Molecular oncology

Background:

• Gliomas are aggressive brain tumors with poor prognosis.
• Immune checkpoint molecule PDL1 (programmed death ligand-1) overexpression correlates with reduced survival in glioma patients.
• MLN4924, a pharmacological inhibitor of cullin neddylation, induces glioma cell apoptosis but stabilizes HIF1A, a PDL1 enhancer.

Purpose of the Study:

• To investigate PDL1 (programmed death ligand-1) upregulation in gliomas following MLN4924 treatment.
• To assess the impact of MLN4924-induced PDL1 on T-cell exhaustion.
• To evaluate the potential of combining MLN4924 with PD1/PDL1 pathway blockade for glioma therapy.

Main Methods:

• Immunohistochemistry, molecular biology, and biochemistry were used to assess PDL1 expression and its role in gliomas.
• In vitro cytotoxicity assays were performed on glioma cell lines treated with MLN4924.
• T-cell based assays were utilized to evaluate T-cell activation and exhaustion.

Main Results:

• PDL1 was confirmed to be overexpressed in clinical glioma samples and cell lines.
• MLN4924 treatment significantly increased HIF1A and PDL1 mRNA and protein levels in glioma cells.
• MLN4924-induced PDL1 caused T-cell exhaustion, which was reversed by PD1/PDL1 blockade.

Conclusions:

• PDL1 upregulation in gliomas presents a viable chemotherapeutic target.
• Combination therapy of MLN4924 with PD1/PDL1 pathway inhibition offers a promising strategy for glioma treatment.