Tumour microenvironment-responsive semiconducting polymer-based self-assembly nanotheranostics.

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Oncology

Background:

• Developing advanced nanoplatforms for cancer theranostics is crucial for improving treatment efficacy and diagnosis.
• Multimodal imaging and combination therapy offer synergistic benefits in cancer management.
• Stimuli-responsive drug delivery systems can enhance therapeutic outcomes and minimize off-target toxicity.

Purpose of the Study:

• To design and evaluate a novel Pt prodrug and gadolinium ion-loaded nanoplatform for multimodal imaging-guided cancer therapy.
• To investigate the pH and thermal sensitivity of the nanoplatform for controlled drug release and combination therapy.
• To assess the diagnostic and therapeutic efficacy of the nanoplatform in a tumor model.

Main Methods:

• Fabrication of a pH and thermal-sensitive polymer-based nanoplatform loaded with a Pt prodrug and gadolinium ions.
• Characterization of nanoparticle stability, drug release kinetics under different pH and temperature conditions.
• Evaluation of multimodal imaging capabilities (photoacoustic/magnetic resonance/positron emission tomography) and T1 relaxivity enhancement.
• Assessment of in vivo tumor accumulation, chemo-photothermal combination therapy efficacy, and tumor eradication.

Main Results:

• The nanoplatform demonstrated stability in physiological environments and controlled drug release under tumor-specific acidic pH and near-infrared (NIR) irradiation.
• Significant enhancement in magnetic resonance (MR) signal (~3-fold increase in T1 relaxivity) was observed in the acidic tumor microenvironment.
• The nanoparticles exhibited excellent tumor accumulation and achieved complete tumor eradication with low-power NIR laser irradiation.
• Reduced side effects on normal organs due to targeted drug release.

Conclusions:

• The developed nanoplatform offers a promising strategy for multimodal imaging-guided chemo-photothermal combination therapy.
• The stimuli-responsive nature of the nanoplatform allows for precise control over drug release and therapeutic effects.
• This approach provides a new avenue for effective cancer diagnosis and treatment with enhanced safety profile.