Abstract
Menstruation is one of the basic but poorly understood life processes in primates during which females shed inner uterine lining every month only to be completely regenerated back within a week. The definitive evidence for the existence and/or identity of stem cells responsible for this process has remained elusive for more than six decades now. Recently, we reported Axin2, a classical Wnt reporter gene, as a marker for endometrial stem cells that also serve as the cells of origin for endometrial cancer.