CXCR4 and neoplasm: Moreover, we observed a reduction in the percentage of epithelial (i.e., EpCAM+) cells within the tumor, and a significant decrease in the percentages of CD133+ and CD133+/CXCR4+ cells within the EpCAM+ cell population, which is in line with our hypothesis that Ru1 affects the CSC compartment (Fig. 3D).