In treatment of hypoxic tumors, oxygen‐dependent photodynamic therapy (PDT) is considerably limited. Herein, a new bimetallic and biphasic Rh‐based core–shell nanosystem (Au@Rh‐ICG‐CM) is developed to address tumor hypoxia while achieving high PDT efficacy. Such porous Au@Rh core–shell nanostructures are expected to exhibit catalase‐like activity to efficiently catalyze oxygen generation from endogenous hydrogen peroxide in tumors. Coating Au@Rh nanostructures with tumor cell membrane (CM) enables tumor targeting via homologous binding. As a result of the large pores of Rh shells and the trapping ability of CM, the photosensitizer indocyanine green (ICG) is successfully loaded and retained in the cavity of Au@Rh‐CM. Au@Rh‐ICG‐CM shows good biocompatibility, high tumor accumulation, and superior fluorescence and photoacoustic imaging properties. Both in vitro and in vivo results demonstrate that Au@Rh‐ICG‐CM is able to effectively convert endogenous hydrogen peroxide into oxygen and then elevate the production of tumor‐toxic singlet oxygen to significantly enhance PDT. As noted, the mild photothermal effect of Au@Rh‐ICG‐CM also improves PDT efficacy. By integrating the superiorities of hypoxia regulation function, tumor accumulation capacity, bimodal imaging, and moderate photothermal effect into a single nanosystem, Au@Rh‐ICG‐CM can readily serve as a promising nanoplatform for enhanced cancer PDT.
Intratumoral hypoxia is a major contributor to multiple drug resistance (MDR) in cancer, and can lead to poor prognosis of patients receiving chemotherapy. Development of an MDR‐inhibitor that mitigates the hypoxic environment is crucial for cancer management and treatment. Reported is a biocompatible and biodegradable catalase‐conjugated iron oxide nanoparticle (Cat‐IONP) capable of converting reactive oxygen species to molecular oxygen to supply an oxygen source for the hypoxic tumor microenvironment. Cat‐IONP demonstrates initial enzymatic activity comparable to free catalase while providing a nearly threefold increase in long‐term enzymatic activity. It is demonstrated that Cat‐IONP significantly reduces the in vitro expression of hypoxia‐inducible factors at the transcription level in a breast cancer cell line. Co‐treatment of Cat‐IONP and paclitaxel (PTX) significantly increases the drug sensitivity of hypoxic‐cultured cells, demonstrating greater than twofold and fivefold reduction in cell viability in comparison to cells treated only with 80 and 120 × 10−6
- NSF-PAR ID:
- 10459454
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 8
- Issue:
- 20
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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