Development of endometrial hyperplasia in Ezh2 cKO uteri. A–D: Hematoxylin and eosin staining of uteri from 8-month–old control (Ctrl; A) and Ezh2 cKO (B–D) mice. B and C: Asterisks indicate cystic glands, whereas the dashed line shows an area with gland crowding, magnified in D. E and F: Vimentin staining in the uteri from control (E) and Ezh2 cKO (F) mice at the age of 8 months. G and H: Ki-67 staining in some abnormal glandular structures in the uteri of Ezh2 cKO mice at the age of 8 months. I–L: Ki-67 staining of control and Ezh2 cKO uteri at the age of 5 months. n = 3 (E–H); n = 2 to 3 (I–L). Scale bars: 250 μm (A and B); 25 μm (C and D); 50 μm (E–H, J, and L); 100 μm (I and K). Original magnification: ×100 (I and K); ×200 (J and L). Myo, myometrium.