Immune Characterization of the Programmed Death Receptor Pathway in High Risk Prostate Cancer.
Baas W, Gershburg S, Dynda D, Delfino K, Robinson K, Nie D, Yearley JH, and Alanee S. Immune characterization of the programmed death receptor pathway in high risk prostate cancer. Clin Genitourin Cancer 2017; 15(5):577-581.
Clin Genitourin Cancer
BACKGROUND: Programmed cell death-1 (PD-1), a T-cell inhibitory receptor, and its ligand, PD-L1, have been reported to be expressed in many tumor types, and this expression has led to the development of many drugs targeting the PD-1 pathway. The objective of this study was to determine the expression of PD-1 and PD-L1 in high-grade prostate cancer tissues, and correlate the expression with disease and patient characteristics.
MATERIALS AND METHODS: Immunohistochemistry for PD-1 (CD279), PD-L1 (B7-H1), and CD3 was performed and scored from 0 to 5 on prostatectomy/biopsy tissue samples taken from 25 men with high-grade prostate cancer. Charts were then retrospectively reviewed for numerous patient and disease characteristics. Statistical analyses were done to investigate the association of these patient and disease characteristics with PD-1, PD-L1, and CD3 expression.
RESULTS: A score of 3 to 5 on the semiquantitative 0 to 5 score was deemed "high" expression whereas a score of 0 to 2 was deemed "low" expression. Of the 25 samples, 2 (8%) scored high for PD-1 expression, 2 (8%) scored high for PD-L1 expression, and 18 (72%) scored high for CD3 expression. There was no statistically significant difference between high and low expression groups of PD-1, PD-L1, or CD3 for any of the variables we collected.
CONCLUSION: An overall low expression of PD-1 and PD-L1, and a concurrent high expression of CD3+ T cells was found in high-risk prostate cancer tissue. No significant association was found between expression of PD-1, PD-L1, or CD3, and patient or disease characteristics. Because of this, one might be able to question the role of PD-L1 in local immune suppression in prostate cancer.
Medical Subject Headings
Aged; B7-H1 Antigen; Biomarkers, Tumor; CD3 Complex; Down-Regulation; Gene Expression Regulation, Neoplastic; Humans; Male; Middle Aged; Neoplasm Grading; Programmed Cell Death 1 Receptor; Prostatectomy; Prostatic Neoplasms; Retrospective Studies; T-Lymphocytes