CAL-130 is a novel phosphoinositide 3-kinase (PI3K) inhibitor. It is reported that combined inhibition of PI3Kγ/δ as therapy for T cell acute lymphoblastic leukemia (T-ALL). In the absence of PTEN phosphatase tumor suppressor function, PI3Kγ or PI3Kδ alone can support leukemogenesis, whereas inactivation of both isoforms suppressed tumor formation. The reliance of PTEN null T-ALL on the combined activities of PI3Kγ/δ was further demonstrated by the ability of a dual inhibitor to reduce disease burden and prolong survival in mice as well as prevent proliferation and promote activation of proapoptotic pathways in human tumors.