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An environment co-contaminated with metals and antibiotics ultimately exposes bacteria to these metals and antibiotics simultaneously. This study aims to explore the efficacy of sublethal concentrations of copper ions contaminated with tetracycline regarding antibiotic resistance in a sensitive strain of E. coli K12. The study proved that a copper ions and tetracycline co-contaminated environment could considerably enhance the mutation frequencies of chloramphenicol and polymyxin B resistance in antibiotic susceptible E. coli; however, the equivalent copper ions and tetracycline alone showed weaker effects. Results also demonstrated that an environment co-contaminated with relatively high sublethal concentrations of copper ion and tetracycline co-contaminated environment could induce much higher antibiotic resistance than the low sublethal and control groups. Whole-genome characterization results indicated that variability existed within the genotype and phenotype involved in antibiotic resistance. Additionally, the evolved resistant strains displayed hereditary resistance after 5 round culture cycles in LB broth over 5 days. Results implied that co-contamination with metals and antibiotics environment could strengthen resistance and contribute to the induction and dissemination of antibiotic resistance in metal and antibiotic co-contaminated environment. [ABSTRACT FROM AUTHOR]

• A novel PDGFB-conjugated copper-gadolinium oxide nanocluster (PDGFB-CGO) was fabricated. • PDGFB-CGO could positively recognize tumor tissue and was effectively internalized within the cancer cells. • PDGFB-CGO showed effective synergistic action of CDT and PTT. • PDGFB-CGO suppressed EMT and tumor angiogenesis, thereby restricting tumor cell migration and invasion. • PDGFB-CGO disrupted the intracellular copper balance, thereby inducing tumor cell apoptosis and anti-angiogenesis. The major hurdles for cancer therapy include controlling tumor growth and metastasis. Herein, we developed a novel platelet-derived growth factor receptor - β (PDGFR - β)-recognizing cyclic peptide (PDGFB)-conjugated copper-gadolinium oxide (CGO) nanocluster (PDGFB-CGO) to suppress tumor growth and metastasis via copper overload-mediated apoptosis and anti-angiogenesis. The developed PDGFB-CGO showed not only ultra-strong Fenton-catalytic activity and PT performance but also excellent T 1 contrast ability. It effectively recognized the tumor tissue, thereby significantly improving its tumor-specific delivery and upon laser irradiation, quickly ablated tumor cells contributing to PTT. In addition, PDGFB-CGO quickly produced abundance of highly active Cu(I) which catalyzed endogenous hydrogen peroxide (H 2 O 2) into hydroxyl radical (·OH), achieving ultra-high cancer CDT efficiency. In addition, the influx of Cu(I) broke copper homeostasis, thereby suppressing epithelial-mesenchymal transition (EMT) and tumor angiogenesis. This process restricted cell migration and invasion, which dramatically blocked cancer metastasis. In addition, the systemic delivery of PDGFB-CGO significantly enhanced the MRI signal in the tumor, which would be beneficial for the accurate diagnosis of cancer. Thus, this work provides a promising strategy to develop advanced biomaterials for efficient theranostic applications in cancer. [ABSTRACT FROM AUTHOR]