Increased expression of genes for basic fibroblast growth factor and transforming growth factor type β2 in human benign prostatic hyperplasia

Abstract
It is now widely accepted that factors other than androgen are crucial in the normal and abnormal growth of the prostate, including human benign prostatic hyperplasia (BPH). Using a Northern blot analysis, we examined human normal and benign hyperplastic prostates for expressions of basic fibroblast growth factor (FGF), acidic FGF, transforming growth factor type β2 (TGF‐β2), TGF‐β1, and epidermal growth factor (EGF). Basic FGF mRNAs were detectable in all the prostates examined. In addition, levels of basic FGF expression were significantly higher in BPH than in normal prostate. Acidic FGF transcripts were undetectable except in one case of BPH. Although both TGFs were expressed in all the samples, TGF‐β2 showed significantly increased levels of expression in BPH as compared to those in normal prostate, while TGF‐β1 did not. No EGF was expressed in any of the prostates examined. These findings suggest that specific growth factors (basic FGF and TGF‐β2) produced locally in the prostate may be involved in BPH development.