SN38-loaded <100 nm targeted liposomes for improving poor solubility and minimizing burst release and toxicity: in vitro and in vivo study

• Published in: International journal of nanomedicine Vol. 13; pp. 2789 - 2802
• Main Authors: Fang, Yi-Ping, Chuang, Chih-Hung, Wu, Yi-Jhun, Lin, Hsin-Che, Lu, Yun-Chi
• Format: Journal Article
• Language: English
• Published: New Zealand Dove Medical Press Limited 01.01.2018; Taylor & Francis Ltd; Dove Medical Press
• Subjects: Acids; Animals; Antineoplastic Agents, Phytogenic - administration & dosage; Antineoplastic Agents, Phytogenic - pharmacokinetics; Biochemistry; Blood; Breast cancer; Camptothecin - administration & dosage; Camptothecin - adverse effects; Camptothecin - analogs & derivatives; Camptothecin - pharmacokinetics; Cancer; Chromatography; Colorectal cancer; Cytotoxicity; Diarrhea; Drug delivery systems; Drug dosages; Drug Liberation; Entrapment; Health aspects; human breast cancer; Humans; Imaging systems; Investigations; Irinotecan; Liposomes - administration & dosage; Liposomes - chemistry; Male; MCF-7 Cells; Metastasis; Mice, Inbred BALB C; Microscopy; Molecular Imaging - methods; Nanoparticles; Nanoparticles - administration & dosage; Nanoparticles - chemistry; Nanoparticles - toxicity; Neutropenia; Original Research; Particle Size; pharmacokinetics; Pharmacy; Physiological aspects; Physiology; Polyethylene glycol; R&D; Research & development; SN-38; Solubility; targeted liposome; Tissue Distribution; Toxicity; Tumors; Vitamin B; Xenograft Model Antitumor Assays; United States > US; Taiwan; toxicity; pharmacokinetics; SN38; targeted liposome; human breast cancer
• ISSN: 1178-2013; 1176-9114; 1178-2013
• DOI: 10.2147/IJN.S158426

SN38 (7-ethyl-10-hydroxycamptothecin) is a camptothecin derivative acts against various tumors. However, SN38 is hydrolyzed in the physiological environment (pH 7.4), and this instability interferes with its potential therapeutic effect. Our objective was to investigate SN38-loaded liposomes to overcome the poor solubility of SN38 and its biodistribution, which further diminish its toxicity. The sub-100 nm targeted liposomes was employed to deliver SN-38 and evaluate the characterization, release behaviors, cytotoxicity, in vivo pharmacokinetics and biochemical assay. The SN38-loaded targeted liposomes consisted of small (100.49 nm) spherical nanoparticles with negative charge (-37.93 mV) and high entrapment efficiency (92.47%). The release behavior of the SN38-loaded targeted liposomes was fitted with Higuchi kinetics ( =0.9860). Free SN38 presented initial burst release. The IC for the SN38-loaded targeted liposomes (0.11 μM) was significantly lower than for the SN38 solution (0.37 μM) in the MCF7 cell line ( <0.01). Confocal laser scanning microscopy also confirmed highly efficient accumulation in the MCF7 cells. Pharmacokinetics demonstrated that the SN38-loaded targeted liposomes had a slightly increased half-life and mean residence time and decreased area under the concentration-time curve and maximum concentration. The results suggested that retention was achieved while the exposure of SN38 was significantly decreased. A noninvasive in vivo imaging system also showed that the targeted liposomes selectively targeted MCF7 tumors. In vivo toxicity data demonstrated that the decrease in platelets was significantly improved by SN38-loaded targeted liposomes, and diarrhea was not observed in BALB/c mice. In summary, SN38-loaded targeted liposomes could be a good candidate for application in human breast cancer.