To further elucidate the relationship between the YAP–FOXD1 axis and human stem cell aging, we examined the expression levels of YAP, pan-TEAD, and FOXD1 in both replicative-senescent (RS) hMSCs and Werner syndrome (WS) hMSCs, a human stem cell model for premature aging disorder WS [37,48]. Here, FOXD1 is linked to Werner syndrome.