OX40 is a member of the tumor necrosis factor receptor family and a potent co-stimulatory pathway that when triggered can enhance T-cell proliferation, memory and antitumor activity.13, 14, 15 It has been shown that the immune-stimulating properties of OX40 agonists can overcome some of the immunosuppressive properties within the tumor microenvironment (TME). The gene discussed is TNFRSF4; the disease is neoplasm.