Applications of ROS-Induced Zr-MOFs Platform in Multimodal Synergistic Therapy

BACKGROUND

Metal-organic frameworks (MOFs) exhibited the adjustable aperture, high load capacities, tailorable structures, and excellent biocompatibilities that have used to be as drug delivery carries in cancer therapy. Until now, Zr-MOFs in particular combine optimal stability towards hydrolysis and postsynthetic modification with low toxicity, and are widely studied for its excellent biological performance.

INTRODUCTION

This review comprises the exploration of Zr-MOFs as drug delivery devices (DDSs) with focus on various new methods, including chemotherapy (CT), photodynamic therapy (PDT), photothermal therapy (PTT), sonodynamic therapy(SDT), radiotherapy, immunotherapy, gene therapy and related combined therapies, which all generate reactive oxygen species (ROS) to achieve the high efficiency of tumor therapy.

CONCLUSION

We described and summarized these pertinent examples of the therapeutic mechanisms and highlight the antitumor effects of their biological application both in vitro and in vivo. The perspectives on their future applications and analogous challenge of the Zr-MOFs materials are given.

Glucose Oxidase-Instructed Traceable Self-Oxygenation/Hyperthermia Dually Enhanced Cancer Starvation Therapy

Cancer theranostics based on glucose oxidase (GOx)-induced starvation therapy has got more and more attention in cancer management. Herein, GOx armed manganese dioxide nanosheets (denoted as MNS-GOx) were developed as cancer nanotheranostic agent for magnetic resonance (MR)/photoacoustic (PA) dual-modal imaging guided self-oxygenation/hyperthermia dually enhanced starvation cancer therapy. The manganese dioxide nanomaterials with different morphologies (such as nanoflowers, nanosheets and nanowires) were synthesized by a biomimetic approach using melanin as a biotemplate. Afterwards, the manganese dioxide nanosheets (MNS) with two sides and large surface area were selected as the vehicle to carry and deliver GOx. The as-prepared MNS-GOx can perform the circular reaction of glucose oxidation and H2O2 decomposition for enhanced starvation therapy. Moreover, the catalytic activity of GOx could be further improved by the hyperthermia of MNS-GOx upon near-infrared laser irradiation. Most intriguingly, MNS-GOx could achieve "turn-on" MR imaging and "turn-off" PA imaging simultaneously. The theranostic capability of MNS-GOx was evaluated on A375 tumor-bearing mice with all tumor elimination. Our findings integrated molecular imaging and starvation-based synergistic cancer therapy, which provided a new platform for cancer nanotheranostics.

Enhanced Radiotherapy using Bismuth Sulfide Nanoagents Combined with Photo-thermal Treatment

Nanotechniques that can improve the effectiveness of radiotherapy (RT) by integrating it with multimodal imaging are highly desirable. Results In this study, we fabricated Bi2S3 nanorods that have attractive features such as their ability to function as contrast agents for X-ray computed tomography (CT) and photoacoustic (PA) imaging as well as good biocompatibility. Both in vitro and in vivo studies confirmed that the Bi2S3 nanoagents could potentiate the lethal effects of radiation via amplifying the local radiation dose and enhancing the anti-tumor efficacy of RT by augmenting the photo-thermal effect. Furthermore, the nanoagent-mediated hyperthermia could effectively increase the oxygen concentration in hypoxic regions thereby inhibiting the expression of hypoxia-inducible factor (HIF-1α). This, in turn, interfered with DNA repair via decreasing the expression of DNA repair-related proteins to overcome radio-resistance. Also, RT combined with nanoagent-mediated hyperthermia could substantially suppress tumor metastasis via down-regulating angiogenic factors. Conclusion In summary, we constructed a single-component powerful nanoagent for CT/PA imaging-guided tumor radiotherapy and, most importantly, explored the potential mechanisms of nanoagent-mediated photo-thermal treatment for enhancing the efficacy of RT in a synergistic manner.