Figure 1.

Expression of SRC-3 in human endometrial cells (A) left column of panels shows low and high power magnification images (top and bottom panels respectively) of human endometrial tissue biopsied during the estrogen-dominant proliferative phase of the menstrual cycle, which was immunohistochemically stained for SRC-3 expression. Note that most glandular epithelial (GE) cells express nuclear localized SRC-3 while stromal cells express lower levels of SRC-3 at this stage of the cycle. Right column of panels displays low and higher magnification images (top and bottom panels respectively) of human endometrial tissue biopsied during the progesterone-dominant secretory phase and stained for SRC-3 expression. Expression of nuclear SRC-3 is clearly detected in the GE cells, which exhibit a distinctive tortuous morphology at this stage of the cycle. Nuclear expression of SRC-3 in the stroma is clearly observed in the majority of cells. Scale bars in the top and bottom left panels apply to the top and bottom right panels respectively. (B) The left two columns show cultured T-HESCs stained with DAPI (blue nucleus) or DAPI (blue) plus phalloidin (green; binds F-actin) on day 0 and 6 of EPC treatment; arrowhead denotes nucleus of T-HESC. On day 0 of EPC treatment, T-HESCs exhibit a fibroblastic morphology with F-actin fibers orientated parallel to each other. Following six days of EPC treatment, note the conspicuous spatial disorganization of the F-actin fibers indicative of cellular transformation from a fibroblastoid to an epithelioid cell morphology (39). The two columns on the right show the same cells immunofluorescently stained for SRC-3 expression [red (arrowhead)] or SRC-3 (red) plus phalloidin (green). Note that SRC-3 is expressed in all T-HESCs at days 0 and 6 of EPC treatment with most of its expression localized to the nucleus (arrowhead). Scale bar applies to all panels.