Characterization of epidermal growth factor receptor in normal and neoplastic human endometrium

Abstract
Growth factors, including epidermal growth factor (EGF), have been implicated in the growth of several types of cancer. This study compares EGF receptors in normal and neoplastic endometrium. Membrane fractions were isolated from surgical specimens. Radioreceptor assays demonstrated the presence of receptors with a dissociation constant of 0.64 nmol/1 in normal endometrium. Affinity crosslinking revealed receptor molecular weight of 150 to 170 kiloDaltons (KD). A survey of samples (n = 37) revealed progressive decrease of EGF receptors in cancers of increasing grade: Grade 1–2 adenocarcinoma decreased 34% from control (n = 6, P < 0.01), whereas Grade 3 adenocarcinoma decreased 90% (n = 7, P P < 0.01). The dissociation constant and molecular weight of the receptor in neoplastic endometrium did not differ significantly from normal. The inverse relationship with grade suggests receptor alteration or down regulation by hormones and/or growth factors.