title: Overcoming the polyethylene glycol dilemma via pathological environment-sensitive change of the surface property of nanoparticles for cellular entry.
abstract: Modification with polyethylene glycol (PEG) is currently considered an important strategy for anti-cancer drug delivery, because PEGylated-nanoparticles would be effectively delivered to tumor tissue by enhanced permeation and retention effects. However, PEGylation suppresses the cellular uptake of nanoparticles (NPs) to target cells (known as the PEG dilemma). Here, we propose a novel strategy, namely conferring a pathological environment-sensitive property of nanoparticles for overcoming the PEG dilemma. Specifically, although nanoparticles have an overall negative surface charge to avoid interactions with biogenic substances in blood circulation, inversion of surface charge (to positive) at the pH of the tumor microenvironment may allow the nanoparticles to be taken up by cancer cells. To prove this concept, charge-invertible nanoparticles modified with novel slightly acidic pH-sensitive peptide (SAPSP-NPs) were developed. The negatively-charged SAPSP-NPs were delivered to tumor tissue, and were successfully taken up by cancer cells upon inversion of the surface charge to positive at intratumoral pH. SAPSP-NPs may serve as an alternative carrier to the PEGylated NP for anti-cancer drug delivery.
authors.affiliation: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Hama
authors.affiliation: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
authors.forename: Shoko
authors.initials: S
authors.lastname: Itakura
authors.affiliation: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Nakai
authors.affiliation: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
authors.forename: Kayoko
authors.initials: K
authors.lastname: Nakayama
authors.affiliation: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Morimoto
authors.affiliation: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Suzuki
authors.affiliation: Department of Biophysical Chemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan. Electronic address: kogure@mb.kyoto-phu.ac.jp.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kogure
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage; D045744:Cell Line, Tumor; D004337:Drug Carriers / Q000737:chemistry / Q000378:metabolism*; D016503:Drug Delivery Systems; D006801:Humans; D006863:Hydrogen-Ion Concentration; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry / Q000378:metabolism*; D009369:Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry / Q000378:metabolism*; D013499:Surface Properties
chemical_list: D000970:Antineoplastic Agents; D004337:Drug Carriers; D010455:Peptides; D011092:Polyethylene Glycols
keywords: Cancer therapy; Charge-inversion; Intratumoral pH; Nanoparticles; Pathological environment-sensitivity