CD73 and PD-L1 expression in WHO grade 1 and grade 2 meningiomas: an exploratory analysis of purinergic and immune-related profiles.

BACKGROUND

Meningiomas are the most common primary central nervous system tumors and exhibit heterogeneous biological behavior across WHO grades. Emerging evidence suggests that purinergic signaling and immune-related pathways may contribute to meningioma biology.

OBJECTIVE

This study evaluated the expression and activity of CD39/ENTPD1 and CD73/NT5E, the expression of PD-L1/CD274, and the systemic inflammatory profile in patients undergoing surgical resection of meningiomas.

RESULTS

Forty patients were included, with specific subgroups available for molecular, immunohistochemical, enzymatic, and cytokine analyses. Molecular comparisons were restricted to WHO grade 1 and grade 2 tumors. NT5E/CD73 expression was higher in WHO grade 2 tumors at both mRNA and protein levels, whereas CD274/PD-L1 expression was lower. Peripheral CD39/CD73 enzymatic activity also differed between study groups, while plasma cytokines showed non-significant trends toward higher concentrations in patients with WHO grade 2 tumors.

CONCLUSION

Given the cross-sectional design, small sample sizes for specific analyses, and the absence of direct measurements of adenosine signaling or longitudinal clinical outcomes, these findings should be interpreted as exploratory patterns associated with tumor grade rather than evidence of tumor progression or a causal mechanism of immune evasion. Overall, the results identify CD73 as a candidate biomarker associated with WHO grade, warranting validation in larger, longitudinal, and mechanistic studies.