Western blot analysis of Hells wild-type (p53/Rb1 DKO and p53 cKO) and Hells-null (p53/Rb1/Hells TKO and p53/Hells DKO) tumors confirmed that HELLS was efficiently knocked-out in these osteosarcomas (Figure 5C). The gene discussed is TP53; the disease is osteosarcoma.