Because IL7R mutant leukemias exhibited clear upregulation of mTOR signaling, we administered the clinical-grade dual PI3K and mTOR inhibitor dactolisib (Fig. 7a) and found it had a striking impact on the frequency of leukemia cells in the blood (Fig. 7b), significantly prolonging the survival of transplanted mice (Fig. 7c). Here, IL7R is linked to leukemia.