The synthesis and X-ray responsive manner of diselenide-bridged silica nanoparticles in chemo-immunotherapy [IMAGE: SIBET]

Despite recent advances in chemotherapeutics, cancer remains a leading cause of disease-related death worldwide. While the clinical outcomes of conventional mono-chemotherapy on cancers remain unsatisfactory, the development of nanomaterials-based drug delivery systems may prove efficient and safe for use in chemotherapy.

In recent years, researchers have been exploring various smart nanocarriers that respond to internal stimuli such as changes in pH, redox potential, and enzymatic activity of tumor microenvironments. Mesoporous organosilica nanoparticles (MONs) are an inorganic-organic hybrid material with large surface area, tunable structure, good biocompatibility and controllable degradation properties which exhibit promising clinical application prospects. To further enhance the control of drug release, there is a critical need to fabricate nanocarriers that can respond to exogenous stimuli such as light, sound, electricity, and magnetism.

Recently, Professor Dong Wenfei’s group from the Suzhou Institute of Biomedical Engineering and Technology (SIBET) cooperated with Professor Shao Dan from South China University of Technology and Professor Kam W. Leong from Columbia University. Together they discovered a new feature of the diselenide-bridged mesoporous organosilica material (10.1002/adma. 201801198); namely that it is an X-ray irradiation degradable material.

Un-released Front Cover of Advanced Materials [IMAGE: ADVANCED MATERIALS]

In their work they optimized the preparation process to obtain diselenide-bridged MONs with moderate particle size, pore size, and selenium content for loading the conventional chemotherapeutic doxorubicin. Such nanodrugs exhibit sensitive and controllable X-ray responsive degradation ability; the matrix can be rapidly disintegrated and the drug explosively released under low-dose X-ray (1 Gy) irradiation.

After cloaking tumor cell-derived cell membranes on the surface of the nanomedicine, the biomimetic nanomedicine achieved tumor-targeted and immune-evasive drug delivery by improving its stability and prolonging blood circulation. It effectively allowed for low-dose X-ray-mediated chemotherapy and significantly reduced the side effects of doxorubicin in vitro and in vivo.

This treatment strategy can also generate tumor-specific immune response by inducing immunogenic death of tumor cells. The combination of this treatment strategy with the use of immune checkpoint blockers can further promote the systemic anti-tumor immune response, which inhibits the growth of both primary and metastatic tumors.

Based on their excellent X-ray responsive degradation, diselenide-bridged MONs can be seen as a potential drug carrier for X-ray-mediated radio-chemotherapy.

As a result of this work, a paper entitled “Biomimetic Diselenide-Bridged Mesoporous Organosilica Nanoparticle as an X-Ray-Responsive Biodegradable Carrier for Chemo-Immunotherapy” was published in Advanced Materials and selected as the front cover image. 

Source: Suzhou Institute of Biomedical Engineering and Technology,

Chinese Academy of Sciences