NOTCH1 and acute lymphoblastic leukemia: HPB-ALL cells with wild-type PTEN, were partially resistant to Compound E. In PTEN-positive HPB-ALL cells, inhibition of NOTCH1 increased expression of PTEN, followed by the PTEN protein level, which inhibited the PI3K-AKT pathway gradually associated with decreasing phosphorylation of Ser473-AKT 11.