Since 2010, our laboratory has been focused on developing nanomaterials, particularly liposomes, to combat cancer by interacting with, and neutralizing CTCs in the circulation.48,66–68,79,86,96,99 The preferred therapeutic is tumor necrosis factor (TNF) apoptosis-inducing ligand (TRAIL), which has shown promise in treating CTCs to reduce the likelihood of metastasis.143 TRAIL is a particularly appropriate therapeutic for this delivery method due to its capability to preferentially induce apoptosis in cancer cells, with minimal toxic side effects to most normal cells. The gene discussed is TNF; the disease is cancer.