PD-L1 (SP263) expression correlates with pathological aggressive parameters in prostate cancer

Objective: Research on the expression of PD-L1 (clone SP263) in prostate cancer (PC) is rare. This study aims to investigate PD-L1 (SP263) expression and its clinicopathological correlations in PC. Methods: A total of 265 PC samples at our center from 2021 to 2024 were included in this study. The clinical information and pathological data were collected. Whole-slide immunohistochemical analysis of PD-L1 (SP263), p53, ERG, PTEN, HER-2 and Ki67 was performed on PC samples, including core biopsies, radical prostatectomies, transurethral resections of the prostate and metastases. Next-generation sequencing was performed in 17 patients and the status of TP53, BRCA1/2 were analyzed. Associations were assessed between PD-L1 status and clinicopathological parameters (age, preoperative serum prostate-specific antigen [PSA], surgical margin, Gleason Group [GG], TNM stage, Ki-67, p53/TP53, BRCA1/2, survival outcomes, etc.) using chi-square, Mann-Whitney U and Kaplan-Meier analyses. Results: PD-L1 positivity (10.2 %, 27/265) correlated with advanced age (P = 0.007), high GG (P = 0.019), T3/4 stage (P = 0.001), positive surgical margin (P = 0.004), aberrant p53/TP53 (P = 0.043), and elevated Ki-67 (P = 0.042). No associations were observed between these factors (serum PSA, N category, M category, PTEN, ERG, BRCA1/2, or survival outcomes) and PD - L1. Conclusion: The expression of PD-L1 (SP263) is positively associated with pathologically aggressive parameters in PC. This finding implies the potential value of PD-L1 as a biomarker for risk stratification. Moreover, it indicates the possibility of using PD-L1 (SP263) and p53 expression to guide the combinational application of mutated p53 inhibitors and PD-1/PD-L1 antibodies in PC.