Stromal Cells, Extracellular Matrix Components, and Adenosine A3 Receptor in Prostate Biopsies: Association With Histological Grade, PSA Levels, and Clinical Tumor Stage.

Prostate cancer (PC) is the second leading cause of cancer-related death in men worldwide. Its progression is marked by significant phenotypic changes in stromal cells and alterations in extracellular matrix (ECM) composition, including variations in collagen fibers, proteoglycans (PGs), and glycosaminoglycans. Tumor cells also modulate ECM secretion through adenosine A3 receptor (A3AR) activity. This study aimed to evaluate stromal cells, ECM components, and A3AR expression in prostate biopsies and explore their association with clinicopathological variables. We analyzed tissue samples from 96 patients diagnosed with PC or benign prostatic hyperplasia (BPH), using immunohistochemistry for alpha-smooth muscle actin and A3AR, and histochemical methods for ECM components. PC samples showed reduced stromal cell content and increased PGs, collagen fibers, and A3AR levels compared with BPH. While we found associations with histological classification, no significant correlations were observed with preoperative prostate-specific antigen levels or clinical risk categories. Our findings suggest that ECM components and A3AR may be involved in PCr progression and hold potential as biomarkers. However, due to the limited number of high-grade cases, further studies are needed to confirm these associations.