title: Antitumor effect of iRGD-modified liposomes containing conjugated linoleic acid-paclitaxel (CLA-PTX) on B16-F10 melanoma.
abstract: In the present study, we prepared a novel delivery system of iRGD (CRGDK/RGPD/EC)-modified sterically stabilized liposomes (SSLs) containing conjugated linoleic acid-paclitaxel (CLA-PTX). The anti-tumor effect of iRGD-SSL-CLA-PTX was investigated on B16-F10 melanoma in vitro and in vivo. The in vitro targeting effect of iRGD-modified SSLs was investigated in a real-time confocal microscopic analysis experiment. An endocytosis-inhibition assay was used to evaluate the endocytosis pathways of the iRGD-modified SSLs. In addition, the in vitro cellular uptake and in vitro cytotoxicity of iRGD-SSL-CLA-PTX were evaluated in B16-F10 melanoma cells. In vivo biodistribution and in vivo antitumor effects of iRGD-SSL-CLA-PTX were investigated in B16-F10 tumor-bearing mice. The induction of apoptosis by iRGD-SSL-CLA-PTX was evaluated in tumor-tissue sections. Real-time confocal microscopic analysis results indicated that the iRGD-modified SSLs internalized into B16-F10 cells faster than SSLs. The identified endocytosis pathway of iRGD-modified SSLs indicated that energy- and lipid raft-mediated endocytosis played a key role in the liposomes' cellular uptake. The results of the cellular uptake experiment indicated that the increased cellular uptake of CLA-PTX in the iRGD-SSL-CLA-PTX-treated group was 1.9-, 2.4-, or 2.1-fold compared with that in the CLA-PTX group after a 2-, 4-, or 6-hour incubation, respectively. In the biodistribution test, the CLA-PTX level in tumor tissues from iRGD-SSL-CLA-PTX-treated mice at 1 hour (1.84±0.17 μg/g) and 4 hours (1.17±0.28 μg/g) was 2.3- and 2.0-fold higher than that of CLA-PTX solution at 1 hour (0.79±0.06 μg/g) and 4 hours (0.58±0.04 μg/g). The value of the area under the curve for the first 24 hours in the tumors of iRGD-SSL-CLA-PTX-treated mice was significantly higher than that in the SSL-CLA-PTX and CLA-PTX solution-treated groups (P<0.01). The in vivo antitumor results indicated that iRGD-SSL-CLA-PTX significantly inhibited the growth of B16-F10 tumors compared with the SSL-CLA-PTX or CLA-PTX solution-treatment groups (P<0.01). The results of tumor-cell apoptosis showed that tumors from the iRGD-SSL-CLA-PTX-treated group exhibited more advanced cell apoptosis compared with the control, CLA-PTX solution-, and SSL-CLA-PTX-treated groups. In conclusion, the antitumor effect of iRGD-SSL-CLA-PTX was confirmed on B16-F10 melanoma in vitro and in vivo.
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Ruo
authors.initials: R
authors.lastname: Du
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Ting
authors.initials: T
authors.lastname: Zhong
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Wei-Qiang
authors.initials: WQ
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Ping
authors.initials: P
authors.lastname: Song
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Wen-Ding
authors.initials: WD
authors.lastname: Song
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China.
authors.forename: Yi-Qun
authors.initials: YQ
authors.lastname: Tang
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing ; State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing ; State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D045744:Cell Line, Tumor; D005260:Female; D053208:Kaplan-Meier Estimate; D044243:Linoleic Acids, Conjugated / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D008545:Melanoma / Q000188:drug therapy / Q000401:mortality; D051379:Mice; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000188:drug therapy / Q000401:mortality; D009842:Oligopeptides / Q000737:chemistry*; D017239:Paclitaxel / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D014018:Tissue Distribution; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D044243:Linoleic Acids, Conjugated; D008081:Liposomes; C569656:N-end cysteine peptide tumor-homing peptide; D009842:Oligopeptides; D017239:Paclitaxel
keywords: CLA-PTX; antitumor effect; iRGD; in vitro; in vivo; peptide-modified liposome