BMI1 and cancer: Second, the elevated expression of LGR5 was associated with an increase in stem cell marker expression while depletion of LGR5 reduced the expression of stem cell markers, such as OCT4, Nanog, Bmi-1 and KLF4 (Figure 7a), all of which have been associated with cancer stemness or been used to isolate CSC subpopulations in vitro and in vivo.