Indeed, we note that Cdkn1a is increased in both DKO leukemias and E2a-/-Lef1F/F leukemias after deletion of Lef1 compared to E2a-/- leukemias suggesting that Cdkn1a could be a TCF1 target that is repressed by LEF1. The gene discussed is LEF1; the disease is leukemia.