MKI67 and premature menopause: For premature ovarian failure (POF), the Liu team introduced MenSC transplantation in bilateral ovaries to treat cyclophosphamide-induced mouse models of POF and found that MenSCs survived at least 14 days in vivo, leading to elevated expression of ovarian granulosa cell markers anti Müllerian hormone, inhibin α/β and follicle-stimulating hormone receptor, and the proliferation marker Ki67 [51].