Mesoporous nanocarriers with a stimulus-responsive cyclodextrin gatekeeper for targeting tumor hypoxia

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cancer Research

Background:

• Tumor hypoxia creates unique reductive environments distinct from normal tissues.
• NAD(P)H:quinone oxidoreductase 1 (NQO1) activity is significantly elevated in hypoxic cancer cells.
• NQO1's heightened activity presents an opportunity for targeted cancer therapy.

Purpose of the Study:

• To develop a drug delivery system that selectively targets hypoxic tumor cells.
• To leverage the enzymatic activity of NQO1 for controlled drug release.
• To design mesoporous silica nanoparticles (MSNs) responsive to hypoxic conditions.

Main Methods:

• Synthesis of mesoporous silica nanoparticles (MSNs) functionalized with an azobenzene linker and drug payload.
• Utilizing the NQO1 enzyme's bioreductive activity to cleave the azobenzene linker.
• Evaluating drug release kinetics in vitro and in vivo under hypoxic and normoxic conditions.
• Characterizing the targeting and release capabilities of the Si-Azo-CD-PEG system.

Main Results:

• The azobenzene linker in MSNs undergoes reductive cleavage specifically triggered by NQO1.
• Controlled drug release from MSNs occurs selectively under hypoxic conditions due to NQO1 activity.
• The developed nanomaterial demonstrated effective drug delivery to hypoxic tumors in vitro and in vivo.
• The azobenzene linker proved effective in constructing NQO1-responsive nanomaterials.

Conclusions:

• Si-Azo-CD-PEG nanoparticles serve as a promising drug delivery carrier for hypoxic cancers.
• The azobenzene linker is a versatile component for designing hypoxia-responsive nanomaterials.
• This approach offers a strategy for targeted cancer therapy by exploiting tumor microenvironment characteristics.