Tumor microenvironment-responsive BSA nanocarriers for combined chemo/chemodynamic cancer therapy

Tumor microenvironment (TME), characterized by high glutathione (GSH), high hydrogen peroxide (H₂O₂) and acidic pH levels, is favorable for the growth, invasion and metastasis of cancer cells. Taking advantage of the specific characteristics of tumors, TME-responsive GCBD NPs are designed to deliver nanoscale coordination polymers (NCPs, GA-Cu) and chemotherapy drugs (doxorubicin, DOX) based on bovine serum albumin (BSA) nanocarriers into cancer cells for combined chemodynamic therapy (CDT) and chemotherapy. In an acidic environment, GCBD NPs could release approximately 90% copper ions, which can not only consume overexpressed GSH to modulate the TME but can also react with endogenous H₂O₂ in a Fenton-like reaction to achieve the CDT effect. Meanwhile, the released DOX could enter the nucleus of tumor cells and affect their proliferation to achieve efficient chemotherapy. Both in vitro and in vivo experiments showed that GCBD NPs had good biosafety and could effectively inhibit the growth of cancer cells. GCBD NPs are promising as a biocompatible nanoplatform to exploit TME characteristics for combined chemo and chemodynamic therapy, providing a novel strategy to eradicate tumors with high efficiency and specificity.