This Article Order Full text via Infotrieve Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Strayer, D. S. Articles by Leibowitz, J. L. Search for Related Content PubMed PubMed Citation Articles by Strayer, D. S. Articles by Leibowitz, J. L.

American Journal of Pathology, Vol 128, 203-209, Copyright © 1987 by American Society for Investigative Pathology

REGULAR ARTICLES

Inhibition of epidermal growth factor-induced cellular proliferation

DS Strayer and JL Leibowitz

The authors tested whether two oncogenic poxviruses, Shope fibroma virus (SFV) and malignant rabbit fibroma virus (MV), coded for an epidermal growth factor (EGF)-like protein. Virus-free lysates of SFV or MV-infected rabbit kidney cells do not appreciably affect proliferation of EGF-unresponsive RK-13 cells. Comparable lysates inhibit the background proliferation of two EGF-responsive cell lines, human foreskin fibroblasts and normal rat kidney cells. Inhibition of EGF-stimulated proliferation is also observed in a dose-dependent fashion. This inhibition is greatest when the virus lysate preparations are added either simultaneously with or before EGF. When EGF is added to cultures 24 hours before the SFV or MV preparations, the latter then have little or no effect on EGF-induced target cell proliferation. The inhibitory factor competed with radiolabeled EGF for its receptor site. Electroblotting shows a protein of 35 kd molecular weight in the lysates of virus-infected RK-13 cells which reacts with anti-EGF antibody. These findings interpreted to indicate that SFV and MV code for an inhibitor of EGF activity, and that this inhibition occurs at least in part by competitive inhibition of EGF-EGF receptor interactions.