Figure 3

Induction of the knockout (KO) of Pten and Arid1a in ovarian endometriosis. (A) Laparotomy findings 6 weeks after the transplantation of small uterine pieces from the donor onto the ovaries and 4 weeks after the DOX treatment. Yellow arrowheads indicate bilateral ovaries. (B) The photo shows the removed uterus and bilateral ovaries (orange arrowheads). Both ovaries are enlarged. (C) Microscopic photographs show the cystic ovarian lesions from each donor type by hematoxylin & eosin (HE) staining and immunostaining for Pax8, Pten, and Arid1a (200×). Epithelial cells from all donor types are positive for Pax8. Cells from Control donor mice (white arrows) keep the expression of both Pten and Arid1a and show no morphological changes with single-layer growth. Cells from iAD donor mice (gray arrows) lack the expression of Arid1a, but show no morphological changes. Cells from iPD donor mice (black arrows) form focal lesions with stratified growth patterns and mild nuclear atypia, corresponding to atypical endometriosis. In this lesion, cells lack the expression of Pten. Cells from iPAD donor mice (yellow arrows) form focal lesions with back-to-back and cribriform growth patterns, stromal invasion, and prominent nuclear atypia, corresponding to endometrioid carcinoma. In this lesion, cells lack the expression of both Pten and Arid1a. (D) The graph shows the ratio of lesion classifications formed by the knockout (KO) induction of Pten and Arid1a by the administration of doxycycline (DOX) in the cystic ovarian lesions of each donor origin. Cysts from Control and iAD show no morphological changes (No atypia). All cysts (100%, 8/8) from iPD are classified as atypical endometriosis (Atypical). Approximately 50% of cysts (50%, 3/6) from iPAD are classified as endometrioid carcinoma (Carcinoma) and the others as atypical endometriosis (50%, 3/6). (E) This case’s implanted site from iPAD did not have a Pax8-positive epithelium (“Failed implant” area enclosed by a dashed line), suggesting engraftment failure.