Interestingly, flow cytometry analysis performed on RCC-41-PDX-1/CD132+-1.1 tumor cell suspensions reveals the presence of three subsets: a first subset of CD133−/EpCAM+ (17%) represents a fraction of non-CSC/RCCs, while two smaller subsets of CD133+/EpCAM− (4%) and CD133+/EpCAM+ (10%) cells (Figure 5D) likely represent RCC-41 CSCs differing for the acquisition of EpCAM [26]. This evidence concerns the gene PROM1 and renal cell carcinoma.