In order to test their in vitro self-renewal potential, sorted RCC-41-PDX-1/CD132+ and unsorted RCC-41-PDX-2 cells were cultured at concentrations ranging from 102 to 1 cell per well in DMEM-LG serum-free medium and assessed for spheroid formation (Figure 3B). Here, PDX1 is linked to renal cell carcinoma.