Involvement of Programmed Cell Death Receptor-1 in Pituitary Adenomas

Abstract

Background and Aim: Pituitary adenomas (PA) are the second most common intracranial neoplasms which can recur despite the treatment with traditional strategies. Cancer cells may evade from immune system cells pretending as host cells using the PD-1/PD-L1 axis which is used in the normal physiological function of T cells, and immunotherapy is based on the disruption of this axis via triggering T cell response. In this case-control study, we aimed to evaluate the PD-1 and PD-L1 protein levels in blood and tumor samples of patients with PA.

Methods: Study samples were obtained from 49 PA patients and 10 healthy controls for PD-1 and PD-L1 expression analysis. PDL1 expression in tissue and blood samples were evaluated by Real-Time Polymerase Chain Reaction. PD-1  levels were measured using a two-site sandwich ELISA kit in plasma samples.

Results: The mean level of expression for PDL1 protein was 60.902±100.171 pg/mL in PA tissues and 1±0 pg/mL in the control samples (p<0.05), whereas the mean expression level of PDL1 in circulation was 13.071±8.071 pg/mL in PA samples and 9.302±2.278  pg/mL in the controls  (p= 0.060). The mean level of PD1 protein was 359.429±476.544 pg/mL in PA and 258.961±65.872 pg/mL in the control samples in the blood (p= 0.135).

Conclusion: PDL1 might serve as a promising candidate for cancer immunotherapy targeting the PD-1/PD-L1 pathway in patients with PA.