MCC and neoplasm: The results demonstrated that in the PBS group, immunosuppressed M2 macrophages were the predominant phenotype, whereas M1 macrophages increased significantly after MCC treatment, and the abundance of M1 macrophages was the highest when the antimicrobial peptide was conjugated, which confirmed that Co2+ and peptides reprogramed the phenotype of tumour-associated macrophages synergistically.