Initially, the TIC population in CRC was identified by the presence of the surface marker CD133, which showed an increased tumorigenic potential in xenografts of immunodeficient mice.7 Despite the description of some surface markers, only an insufficient purity of TICs can be achieved so far and their biology remains undefined.8 Hence, identifying the regulatory mechanisms and signaling pathways involved in TICs, and developing targeted therapy, might raise promising strategies in the treatment of CRC. The gene discussed is PROM1; the disease is colorectal carcinoma.