'Sense-and-Treat' DNA Nanodevice for Synergetic Destruction of Circulating Tumor Cells

DNA nanostrucures are promising materials for biomedical applications. Herein, we established a “sense-and-treat” localized drug delivery system based on a DNA nanodevice to specifically destroy circulating tumor cells (CTCs) by synergetic chemotherapy and photodynamic therapy. The DNA nanodevices could sense the existence of CTCs and treat CTCs with anticancer agents. Typically, the presence of target cell promoted the formation of hairpin structure of aptamer, and then the aptamer-accompanied DNA tetrahedron would release from the supporter. The chemotherapy drugs (doxorubicin, Dox) loaded in DNA tetrahedron would destroy the CTCs specifically. Moreover, the photosensitizer labeled on DNA tetrahedron would be activated by lights and generated toxic 1O2, once DNA nanodevices bound CTCs flow through the superficial capillary. Unlike the aptamer only labeled with photosensitizer, the DNA nanodevice showed the capability to promote cellular internalization of anticancer agents, increase drug loading capacit...