CD274 and neoplasm: Additionally, once the nitroimidazole groups in this nanomedicine were reduced to the hydrophilic aminoimidazole groups by NADPH in tumor cells, the UCST of PAAN copolymer could be automatically decreased to the point below the physiological temperature by alternating the hydrophilicity to hydrophobicity ratio, causing the rapid disintegration of this nanomedicine and on‐demand release of the PD‐L1 inhibitor BMS202.