RELATIONSHIP BETWEEN EPIDERMAL GROWTH-FACTOR AND ITS RECEPTOR IN HUMAN BENIGN PROSTATIC HYPERPLASIA

Human benign prostatic hyperplasia (BPH) samples were analyzed to eval uate the presence of immunoreactive epidermal growth factor (irEGF) an d EGF receptor (EGFR). In all BPH samples examined both peptide and it s receptor were present. Scatchard analysis of binding data of [I-125] EGF showed two classes of binding sites with high and low affinity. In tratissular irEGF concentrations showed a significant inverse linear c orrelation with EGFR levels. Two groups of samples can be identified: the first showing high irEGF concentrations and low levels of EGF bind ing sites; the second low irEGF and high concentrations of EGFR. The s imultaneous presence of EGF and its receptor in BPH samples indicates that this growth factor may act in an autocrine/paracrine manner in hu man prostatic tissue. The inverse relationship between EGF and the two sites of EGFR lead one to hypothesize that EGF itself could play a ce ntral role in determining receptor cell surface availability.