EXPRESSION OF TRANSFORMING GROWTH-FACTOR-BETA-1 MESSENGER-RIBONUCLEIC-ACID AND THE MODULATION OF DEOXYRIBONUCLEIC-ACID SYNTHESIS BY TRANSFORMING GROWTH-FACTOR-BETA-1 IN HUMAN ENDOMETRIAL CELLS

OBJECTIVE: The purpose of this study was (1) to evaluate the potential sites of transforming growth factor-beta 1 synthesis in human endomet rium by analyzing separated endometrial glands and stromal cells for t ransforming growth factor-beta 1 messenger ribonucleic acid by Norther n analysis of total ribonucleic acid and (2) to investigate the effect s of transforming growth factor-beta 1 on deoxyribonucleic acid synthe sis in endometrial epithelial and stromal cells in culture. STUDY DESI GN: Endometrial glands and stroma from proliferative and secretory end ometrium were isolated after collagenase treatment of endometrial tiss ue minces and were analyzed for transforming growth factor-beta 1 mess enger ribonucleic acid by Northern analysis. We studied the effects of estradiol-17 beta and transforming growth factor-beta 1 on deoxyribon ucleic acid synthesis in endometrial epithelium and transforming growt h factor-beta 1 on stromal cells in culture by evaluating tritiated th ymidine incorporation into trichloroacetic acid-precipitable material. RESULTS: Transforming growth factor-beta 1 messenger ribonucleic acid was detected for Northern analysis in separated endometrial stromal c ells in levels that were greatest during the secretory phase and in gr eater levels than in epithelial cells from that same tissue. Transform ing growth factor-beta 1 messenger ribonucleic acid in glandular epith elium in culture was not increased to detectable levels by treatment w ith transforming growth factor-beta. Deoxyribonucleic acid synthesis i n endometrial glandular epithelium was inhibited by transforming growt h factor-beta 1, but transforming growth factor-beta 1 stimulated deox yribonucleic acid synthesis in endometrial stromal cells in culture. A fter treatment for 5 days with estradiol-17 beta (10(-8) mol/L), deoxy ribonucleic acid synthesis in endometrial glands in culture was decrea sed by 40%. Transforming growth factor-beta 1 (1 ng/ml) did not alter this effect of estradiol-17 beta on deoxyribonucleic acid synthesis. C ONCLUSIONS: Transforming growth factor-beta 1 acts to decrease deoxyri bonucleic acid synthesis in epithelial cells and to increase it in str omal cells isolated from human endometrium and maintained in monolayer culture. Transforming growth factor-beta 1, potentially of stromal ce ll origin, could participate in the regulation of endometrial cell pro liferation and differentiation in vivo.