A, RB was efficiently deleted in the uterine epithelium of uterine epithelium-specific conditional knockout mice (Rb1 eKO mice). Scale bar = 100μm. Rb1 eKO mice, Rb1loxP/loxPLtfCre/+ mice; Rb1 eControl mice (littermate controls of Rb1 eKO mice), Rb1loxP/loxP mice; le, luminal epithelium; s, stroma. 