Our findings suggested that, to minimize off-target effects and to benefit from the optimal response, selective inhibitors targeting the PI3K/Akt/mTOR may represent a new promising treatment for T-ALL patients, since they showed a strong cytotoxicity against leukemic T-cells or T-lymphocytes stimulated to proliferate, whereas they did not compromise viability of quiescent healthy CD4+ T lymphocytes. The gene discussed is CD4; the disease is acute lymphoblastic leukemia.