FIGURE 5.

BMI1 overexpression overcomes inhibition of mammosphere formation by PLK1 knockdown. Control (pMSCV) and BMI1 (pMSCV-BMI1) overexpressing MCF7 and MDA-MB-231 cells expressing a control sh RNA or PLK1 sh RNAs (PLKi46 and PLKi47) (as indicated) were studied for mammosphere formation as described in Fig. 4A. In this case, the shRNA vector expresses GFP, hence mammospheres were photographed using a FITC filter (10× mag). Error bars represent ± S.D. *, p < 0.05 (significant); NS, not significant.