Zusammenfassung
The role of estrogen receptor beta (ER beta) in pathogenesis of endometriosis remains to be elucidated. In this study, we have examined the expression of the four main ER beta transcript isoforms in human endometrial tissue in women with or without endometriosis. Total RNA was isolated from native endometrial tissue and transcript levels of ER alpha, beta 1, beta 2, beta 4, beta 5 were analyzed ...
Zusammenfassung
The role of estrogen receptor beta (ER beta) in pathogenesis of endometriosis remains to be elucidated. In this study, we have examined the expression of the four main ER beta transcript isoforms in human endometrial tissue in women with or without endometriosis. Total RNA was isolated from native endometrial tissue and transcript levels of ER alpha, beta 1, beta 2, beta 4, beta 5 were analyzed by means of RT-PCR. We compared the results with regard to menstrual cycle phase as well as to presence or absence of endometriosis. We prospectively harvested the endometrium of ten women without endometriosis (five for each cycle phase) and eight patients with endometriosis (five in the proliferative phase, three in the secretory phase). ER alpha, beta 1, beta 2, and beta 5 transcripts were detected in both cycle phases. During the proliferative phase, healthy women had a significantly higher ER alpha/ER beta 1-ratio than patients with endometriosis. Irrespective of the cycle phase, ER alpha-mRNA level was significantly higher than transcript levels of ER beta isoforms. ER alpha, beta 1, beta 2, and beta 5 are expressed in human endometrium. The individual receptors differed in terms of expression strength but there was no relevant change during the cycle. The decreased ER alpha/ER beta 1-ratio in proliferative endometrium of endometriosis patients suggest that ER beta 1 might be involved in the pathogenesis of endometriosis. Further studies should be undertaken to substantiate the role of ER beta in endometrial pathology.