pH-sensitive drug-delivery systems for tumor targeting.
1Key Laboratory of Smart Drug Delivery, Ministry of Education, Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai 201203, China.
Therapeutic Delivery
|December 6, 2013
Summary
This review explores stimuli-responsive drug delivery systems that target tumors. Acidic pH-triggered nanoparticles enhance drug release within tumor cells, improving cancer therapy and overcoming drug resistance.
Area of Science:
- Biomedical Engineering
- Nanotechnology
- Oncology
Background:
- Solid tumors exhibit a lower extracellular pH compared to normal tissues.
- Tumor cells internalize drugs via endosomes and lysosomes, which have acidic internal environments.
- Traditional drug delivery often struggles with tumor specificity and overcoming multidrug resistance.
Purpose of the Study:
- To review stimuli-responsive drug delivery systems for enhanced tumor targeting.
- To explain the role of acidic pH in the tumor microenvironment and intracellular organelles.
- To discuss strategies for improving tumor-specific drug delivery and efficacy.
Main Methods:
- Review of existing literature on pH-responsive drug delivery systems.
- Analysis of nanoparticle behavior in acidic tumor microenvironments.
- Discussion of endosome/lysosome pH-triggered drug release mechanisms.
Main Results:
- Drug delivery systems can be designed to respond to the acidic extracellular pH of tumors.
- Nanoparticles can be engineered for pH-triggered drug release within tumor cells.
- Acidic pH-responsive systems show potential for overcoming multidrug resistance.
Conclusions:
- Stimuli-responsive drug delivery systems offer a promising strategy for targeted cancer therapy.
- Exploiting the acidic tumor microenvironment and endosomal/lysosomal pH can improve drug efficacy.
- Further development of pH-sensitive nanocarriers can enhance tumor treatment outcomes.
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