MRC1 and neoplasm: proved that low molecular weight HA modified black phosphorus (BP) nanoparticles (HA‐BP) could successfully reeducate M2‐like macrophages into M1 phenotype with down‐regulated CD206 and increased CD86 expression, which was closely related to the capability of HA facilitating M1‐polarization.[160] The HA‐BP could markedly reprogram tumor‐supportive TAMs and reduce 4T1 tumor growth.