For example, Ricci-Vitiani et al. [37] showed that tumorigenic cells in colon cancer population (with CD133+ marker) accounts for about 2.5% of the tumor cells and Korkaya et al. [38] determined that CSCs comprise 1–5% of primary tumors in human mammary carcinomas. This evidence concerns the gene PROM1 and malignant colon neoplasm.