In vivo assessment of the regulation of transforming growth factor alpha, epidermal growth factor (EGF), and EGF receptor in the human endometrium by medroxyprogesterone acetate.
OBJECTIVE
The present study evaluated the in vivo effect of medroxyprogesterone acetate (MPA) on the localization of immunoreactive transforming growth factor alpha (TGFalpha), epidermal growth factor (EGF), and their common receptor (EGF-R) in the human endometrium.


METHODS
The study design was a randomized clinical trial enrolling 36 healthy women with regular menstrual cycles. The participants were randomly assigned into three groups: groups 1 (n = 11) and 2 (n = 17) received placebo and were submitted to endometrial biopsy during the proliferative and secretory phases of menstrual cycle, respectively; group 3 (n = 8) received MPA (10 mg/day) for 10 days followed by endometrial biopsy, which was performed during the secretory phase. Immunohistochemistry was used to localize TGFalpha, EGF, and EGF-R in the endometrial tissue.


RESULTS
TGFalpha was present markedly in the luminal and glandular epithelia but also in the periglandular stroma, with a distribution pattern similar in the three experimental groups. EGF immunostaing was equally distributed in epithelial and stromal layers of the endometrium and remained unchanged in endometrial samples from women treated with MPA compared to placebo. EGF-R was expressed only in the epithelium. The intensity of EGF-R immunostaining was higher in secretory than in proliferative endometrium and was further increased by administration of MPA (p < 0.05, chi-square test).


CONCLUSIONS
The present results suggest that the progestogen-induced in vivo differentiation of secretory endometrium does not require dramatic changes in the expression of EGF or TGFalpha, whereas EGF-R may be up regulated.
Reis
Fernando M
FM
Gynecological Endocrinology Unit, Division of Endocrinology, Hospital de Clínicas, Department of Physiology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Lhullier
Cintia
C
Edelweiss
Maria Isabel
MI
Spritzer
Poli Mara
PM
D000328:Adult; D001706:Biopsy; D004717:Endometrium / Q000187:drug effects* / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000378:metabolism*; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017258:Medroxyprogesterone Acetate / Q000494:pharmacology*; D008597:Menstrual Cycle / Q000502:physiology; D008875:Middle Aged; D011374:Progesterone / Q000097:blood; D016211:Transforming Growth Factor alpha / Q000378:metabolism*
D016211:Transforming Growth Factor alpha; D011374:Progesterone; D004815:Epidermal Growth Factor; D017258:Medroxyprogesterone Acetate; D066246:ErbB Receptors