Together with our prior results indicating that these immune agonists have high efficacy and safety if confined to the tumor microenvironment11, these results prompted us to test the utility of nanoparticle-IL-2/anti-CD137 formulations designed to rapidly accumulate in tumors while minimizing systemic exposure, through the enhanced permeation and retention (EPR) effect. The gene discussed is TNFRSF9; the disease is neoplasm.