Figure 2.

Endometrial organoids express sex hormone receptors and exhibit structural organization. Organoids were observed after 14 days of stepwise hormone treatment mimicking the follicular phase of a normal menstrual cycle. Levels of (A) estrogen receptor, (B) androgen receptor, and (C) progesterone receptor were detected by immunohistochemical staining in endometrial organoids. (D) Proliferation was assessed in the organoids as indicated by Ki67 immunoreactivity. (E, F) Cell specific markers were assessed by immunofluorescent staining of E-cadherin, pan-cytokeratin (epithelial), and vimentin (stromal), which revealed structural organization of the cells in the organoids.