title: Well-Defined Redox-Sensitive Polyethene Glycol-Paclitaxel Prodrug Conjugate for Tumor-Specific Delivery of Paclitaxel Using Octreotide for Tumor Targeting.
abstract: A redox-sensitive prodrug, octreotide(Phe)-polyethene glycol-disulfide bond-paclitaxel [OCT(Phe)-PEG-ss-PTX], was successfully developed for targeted intracellular delivery of PTX. The formulation emphasizes long-circulation-time polymer-drug conjugates, combined targeting based on EPR and OCT-receptor mediated endocytosis, sharp redox response, and programmed drug release. The nontargeted redox-sensitive prodrug, mPEG-ss-PTX, and the targeted insensitive prodrug, OCT(Phe)-PEG-PTX, were also synthesized as controls. These polymer-PTX conjugates, structurally confirmed by 1H NMR, exhibited approximately 23,000-fold increase in water solubility over parent PTX and possessed drug contents ranging from 11% to 14%. The redox-sensitivity of the objective OCT(Phe)-PEG-ss-PTX prodrug was verified by in vitro PTX release profile in simulated reducing conditions, and the SSTRs-mediated endocytosis was demonstrated by flow cytometry and confocal laser scanning microscopy analyses. Consequently, compared with mPEG-PTX and OCT(Phe)-PEG-PTX, the OCT(Phe)-PEG-ss-PTX exhibited much stronger cyotoxicity and apoptosis-inducing ability against NCI-H446 tumor cells (SSTRs overexpression), whereas a comparable cytotoxicity of these prodrugs was obtained against WI-38 normal cells (no SSTRs expression). Finally, the in vivo studies on NCI-H466 tumor-bearing nude mice demonstrated that the OCT(Phe)-PEG-ss-PTX possessed superior tumor-targeting ability and antitumor activity over mPEG-PTX, OCT(Phe)-PEG-PTX and Taxol, as well as minimal collateral damage. This targeted redox-sensitive polymer-PTX prodrug system is promising in tumor therapy.
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Tingjie
authors.initials: T
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Qu
authors.initials: Q
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Lifang
authors.initials: L
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Meirong
authors.initials: M
authors.lastname: Huo
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008823:Micelles; D015282:Octreotide / Q000737:chemistry*; D010084:Oxidation-Reduction; D017239:Paclitaxel / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D011355:Prodrugs / Q000737:chemistry*; D055752:Small Cell Lung Carcinoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D014407:Tumor Cells, Cultured; D023041:Xenograft Model Antitumor Assays
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004337:Drug Carriers; D008823:Micelles; D011108:Polymers; D011355:Prodrugs; D011092:Polyethylene Glycols; D017239:Paclitaxel; D015282:Octreotide
keywords: octreotide; paclitaxel; prodrug conjugate; redox-sensitive; tumor therapy