In summary, we have discovered a highly selective and potent PI3Kδ/Vps34 dual kinase inhibitor, PI3KD/V-IN-01, which exerts better anti-proliferative effects against the majority of B-cell related malignancies that we tested (AML, CLL and B-NHL) as compared to individual targeted PI3Kδ and Vps34 inhibitors. The gene discussed is PIK3C3; the disease is B-cell chronic lymphocytic leukemia.