Infiltrating immune cells in prostate cancer tissue after androgen deprivation and radiotherapy.

ABSTRACT:

Objectives

Androgen deprivation therapy (ADT) has long been a cornerstone in treatment of advanced prostate cancer (PCa), and is known to improve the results of radiotherapy (RT) for high-risk disease. The purpose of our study was to use a multiplexed immunohistochemical (mIHC) approach to investigate the infiltration of immune cells in PCa tissue after eight weeks of ADT and/or RT with 10 Gy.

Methods

From a cohort of 48 patients divided into two treatment arms, we obtained biopsies before and after treatment and used a mIHC method with multispectral imaging to analyze the infiltration of immune cells in tumor stroma and tumor epithelium, focusing on areas with high infiltration.

Results

Tumor stroma showed a significantly higher infiltration of immune cells compared to tumor epithelium. The most prominent immune cells were CD20⁺ B-lymphocytes, followed by CD68⁺ macrophages, CD8⁺ cytotoxic T-cells, FOXP3⁺ regulatory T-cells (Tregs), and T-bet⁺ Th1-cells. Neoadjuvant ADT followed by RT significantly increased the infiltration of all five immune cells. Numbers of Th1-cells and Tregs significantly increased after single treatment with ADT or RT. In addition, ADT alone increased the number of cytotoxic T-cells and RT increased the number of B-cells.

Conclusions

Neoadjuvant ADT in combination with RT results in a higher inflammatory response compared to RT or ADT alone. The mIHC method may be a useful tool for investigating infiltrating immune cells in PCa biopsies to understand how immunotherapeutic approaches can be combined with current PCa therapies.

SUBMITTER: Erlandsson A 

PROVIDER: S-EPMC9996739 | biostudies-literature | 2023 Jan-Dec

REPOSITORIES: biostudies-literature