Angelw Chem: cancer immunotherapy with nano artificial enzyme in Central South University

February 11, 2020 / BIOON / -- in theory, our immune system can detect and kill cancer cells Unfortunately, the tumor is ready for these attacks Despite modern cancer treatment, metastasis and recurrence remain a major problem The enhancement of antitumor immunity is now possible thanks to the mimicry of the enzyme's copper telluride nanoparticles, especially under nir-ii light As reported by Chinese scientists in angelwandte Chemie, this process can induce oxidative stress in tumor cells, destroy their immunosuppressive state and trigger the inflammatory process The structure of these nanoparticles is completely different from that of enzyme, but they can simulate the catalytic activity of enzyme They are easier to prepare, cheaper and more stable than natural enzymes Wansong Chen of Central South University, in collaboration with you Nian Liu, has now launched a new kind of nano enzyme: copper telluride nanoparticles (Cu2 xTe), which simulates the activities of glutathione oxidase and peroxidase The activity of the enzyme is due to the conversion of copper ions between two oxidation states The substrate is glutathione, an antioxidant The concentration of glutathione in tumor cells is significantly higher than that in healthy cells This is why nanoenzymes only work in tumor cells In addition, they also absorb nir-ii light (near-infrared light with wavelengths between 1000 and 1350 nm), which causes their environment to heat up This effect strongly increased the enzyme like activity of nano enzyme In the treatment, nir-ii irradiation can be selectively applied to tumors Experiments on tumor cell culture and tumor bearing mice show that the use of nano enzyme and nir-ii irradiation can cause a series of cell responses, greatly increase the oxidative stress in the tumor, and eventually lead to cell death At the same time, the inhibition of immune process by tumor microenvironment was relieved Instead, substances that promote inflammation are released and trigger an immune response The increased concentration of effector T cells also supports this conclusion Therefore, the immune system can learn to defend against metastasis and establish "immune memory" to prevent recurrence Reference: Liu Younan et al Artistic enzyme catalyzed cascade reactions: ANTIUMOR immunology reinforced by nir-ii high t Angewandte chemistry 2019 Doi: https://doi.org/10.1002/anie.201909729