title: pH-sensitive drug-delivery systems for tumor targeting.
abstract: Drug-delivery system responses to stimuli have been well investigated recently. As pH decrease is observed in most solid tumors, drug-delivery systems responsive to the slightly acidic extracellular pH environment of solid tumors have been developed as a general strategy for tumor targeting. Drug vehicles that are sensitive to acidic endosome/lysosome pH have been constructed for efficient drug release in tumor cells. This review explains the mechanisms of acidic pH in the tumor microenvironment and endocytic-related organelles, endosomes and lysosomes. Nanoparticle responses to acidic extracellular pH are discussed, along with approaches for improving tumor-specific therapy. Endosome/lysosome pH-triggered vehicles are reviewed, which achieve rapid drug release in tumor cells and overcome multidrug resistance.
authors.affiliation: Key Laboratory of Smart Drug Delivery, Ministry of Education, Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai 201203, China.
authors.forename: Xi
authors.initials: X
authors.lastname: He
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Li
authors.forename: Sai
authors.initials: S
authors.lastname: An
authors.forename: Chen
authors.initials: C
authors.lastname: Jiang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000627:therapeutic use*; D016503:Drug Delivery Systems / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008024:Ligands; D053758:Nanoparticles; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D059016:Tumor Microenvironment
chemical_list: D000970:Antineoplastic Agents; D008024:Ligands