Although CB839 has been shown to have an inhibitory capacity (IC50) in the nanomolar range in sensitive cancers, it appears to inhibit proliferation without inducing apoptosis in endothelial cells in the micromolar range, while we have showed that proliferation of CD4+ T cells is not significantly reduced by concentrations up to 5 micromolar (125, 126). The gene discussed is CD4; the disease is cancer.