Cytokine Networks and Prostate Growth: Immune Mechanisms in the Development of BPH
Benign prostatic hyperplasia (BPH) is a highly prevalent, age-associated condition characterized by nonmalignant enlargement of the prostate and a spectrum of lower urinary tract symptoms (LUTS). While androgen signaling and stromal–epithelial interactions are classic drivers of BPH, a large body of evidence now supports chronic, low-grade inflammation as a coequal engine of prostate growth and symptom progression. Inflammatory infiltrates in BPH tissue, typically macrophages, T cells, mast cells, and occasional neutrophils, create a cytokine-rich microenvironment that sustains epithelial and stromal proliferation, extracellular matrix (ECM) remodeling, angiogenesis, and smooth muscle hypercontractility. Cytokine networks rather than single mediators appear to determine biological outcomes: pro-growth and pro-fibrotic axes (eg, IL-6/STAT3, IL-8/CXCR signaling, TNF-α/NF-κB, IL-17–driven amplification loops, and TGF-β–mediated myofibroblast activation) intersect with counter-regulatory pathways (eg, IL-10, TGF-β immunoregulation, and specialized pro-resolving mediators) that may be insufficient or dysregulated in progressive disease. These immune signals interact with endocrine aging, metabolic syndrome, oxidative stress, local hypoxia, and recurrent infection or tissue injury, producing a “wound that does not heal” phenotype in the transitional zone. This review synthesizes current concepts on how cytokine networks shape the BPH microenvironment, linking immune cell recruitment and activation to prostate enlargement, fibrosis, and LUTS, and highlights emerging biomarker and therapeutic opportunities targeting inflammation-driven prostate growth.