Many OVs and viral vectors armed with CD40L have been tested in clinical [53,54,55,56] and preclinical [50,57,58] settings and have been shown to exert multiple antitumoral activities including tumor growth control, cancer cell apoptosis, induction of T-cell responses, increase in T-effector/T-reg cell ratios, and upregulation of Th1 cytokines. This evidence concerns the gene CD40LG and neoplasm.