Epidermal Growth Factor Enhances Secretion of the Ovarian Tumor-Associated Cancer Antigen CAI25 From the Human Amnion WISH Cell Line

Abstract

OBJECTIVE : We studied the relation between epidermal growth factor (EGF)/epidermal growth factor receptor (EGFR) and CA125 production in WISH cells.

METHODS: We investigated quantitatively and immunohistochemically EGF-stimulated CA125 release from WISH cells and the effect of EGF on CA125 phosphorylation.

RESULTS: Immunohistochemical staining demonstrated that CA125 and EGFR expression on the plasma membrane of the WISH cells was closely correlated with cell density. The WISH cell monolayers (day 4) stained for CA125 in both the cytoplasm and plasma membrane. By day 8, cells began to form clumps in the surrounding monolayer that were positive for membrane- associated CA125 and EGFR, while the monolayer was almost negative for both molecules. Four-day and 8-day cells exposed to EGF demonstrated a loss of both CA125 and EGFR staining. Epidermal growth factor increased the secreted CA125 levels by 50% in day-4 cells but had no effect on day-8 cells. CA125 from WISH cells was phosphorylated, and EGF further enhanced this phosphorylation.

CONCLUSION: Release of CA125 from the plasma membrane is enhanced by EGF and may be regulated by phosphorylation. (J Soc Gynecol Invest 1994;1:89-96)