To confirm the relevance of our findings in vivo and in human cancers, we also use the Pten null prostate cancer and T-ALL mouse models, as they closely mimic the clinical features of these human cancers with high frequencies of PTEN mutation and PI3K pathway activation19–22, as well as the PTEN null human prostate cancer and T-ALL cell lines. This evidence concerns the gene PTEN and acute lymphoblastic leukemia.