Epidermal growth factor in human endometrium: proliferative effects in culture and immunocytochemical localization in normal and endometriotic tissues.

Endometrial proliferation is stimulated by oestradiol. The precise mechanism is poorly understood, but may be mediated by epidermal growth factor (EGF). The aim of the present study was to assess the effects of oestradiol and EGF on glandular and stromal proliferation in human endometrial cell cultures, and to determine the localization of EGF-like immunoreactivity (EGF-IR) using immunocytochemistry in normal and endometriotic tissue. Endometrium was obtained from women undergoing curettage or hysterectomy for benign disease, or laparoscopy for endometriosis. For tissue culture experiments, enriched glandular and stromal cells were prepared by digestion with collagenase and DNAase, and cultured for 4 days with oestradiol or EGF, both alone and in combination. Immunocytochemical studies were performed using sheep primary antibody against EGF, with binding visualized using the unlabelled antibody--enzyme method. In combination, oestradiol and EGF increased mean cell counts from 1.15 +/- 0.06 and 1.36 +/- 0.05 x 10(5)/ml to 1.68 +/- 0.1 (+46%) and 1.94 +/- 0.16 (+43%) x 10(5)/ml, in proliferative and secretory gland preparations respectively (n = 10, P less than 0.01). No effect was seen in stromal cell preparations; however the stimulation in gland preparations was further augmented after the addition of stromal-conditioned medium. EGF-IR was detected in endometrium from normal women, and in normal and ectopic endometrium from women with endometriosis. EGF-IR was seen in glands and stroma and was not related to the phase of the menstrual cycle. EGF may play a role in the oestrogen-stimulated proliferation of normal and endometriotic endometrium.