It has been demonstrated that stromal prostate cells in BPH tissue can act as antigen-presenting cells (APC) and activate antigen-specific CD4+ T cells to release IL-17 and IFN-γ, stimulating the release of IL-6 (a potent autocrine growth factor) and IL-8 (a paracrine inducer of fibroblast growth factor 2) which are the main inducer of stromal and epithelial prostate cells growth and proliferation (82). This evidence concerns the gene IL17A and benign prostatic hyperplasia.