KGF AND EGF DIFFERENTIALLY REGULATE THE PHENOTYPE OF PROSTATIC EPITHELIAL-CELLS

Previous studies indicate that keratinocyte growth factor (KGF) acts a s a paracrine factor in the prostatic epithelium and epidermal growth factor (EGF) acts as an autocrine factor. In serum-free medium, KGF or EGF promoted similar growth of human prostatic epithelial cells. Resp onse to two growth-inhibitory factors (suramin and transforming growth factor-beta), and expression of keratins and prostate-specific antige n (PSA), were similar with either mitogen. However, colonies in medium with KGF were very compact with extensive intercellular bonds, wherea s colonies with EGF consisted of widely-separated cells. Growth was de creased to a greater extent by deletion of growth factors from medium with KGF versus EGF, and retinoic acid was 10-foid more potent at indu cing growth inhibition and differentiation-associated keratin with KGF compared to ECP. We conclude that regulation of growth and differenti ation in the prostate might vary depending on the availability of KGF versus EGF.