Tumor-targeted PE38KDEL delivery via PEGylated anti-HER2 immunoliposomes

• Published in: International journal of pharmaceutics 2009-06, Vol.374 (1), p.145-152
• Main Authors: Gao, Jie, Zhong, Wei, He, Jinqiu, Li, Huimei, Zhang, He, Zhou, Guichen, Li, Bohua, Lu, Ying, Zou, Hao, Kou, Geng, Zhang, Dapeng, Wang, Hao, Guo, Yajun, Zhong, Yanqiang
• Format: Article
• Language: English
• Subjects: ADP Ribose Transferases - immunology; ADP Ribose Transferases - pharmacokinetics; ADP Ribose Transferases - pharmacology; Bacterial Toxins - immunology; Bacterial Toxins - pharmacokinetics; Bacterial Toxins - pharmacology; Biological and medical sciences; Breast cancer; Breast Neoplasms - drug therapy; Breast Neoplasms - immunology; Cell Line, Tumor; Cytotoxicity; Drug Delivery Systems; Exotoxins - immunology; Exotoxins - pharmacokinetics; Exotoxins - pharmacology; Female; Flow Cytometry; General pharmacology; Half-Life; Humans; Immunoglobulin Fab Fragments - immunology; Liposomes; Medical sciences; Particle Size; PE38KDEL; PEGylated immunoliposomes; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Polyethylene Glycols - chemistry; Pseudomonas aeruginosa Exotoxin A; Receptor, ErbB-2 - immunology; RhuMAbHER2; Sulfhydryl Compounds - chemistry; Virulence Factors - immunology; Virulence Factors - pharmacokinetics; Virulence Factors - pharmacology
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/j.ijpharm.2009.03.018

We previously reported the development of PE38KDEL-loaded anti-HER2 poly(lactic-co-glycolic acid) (PLGA) nanoparticles that bind and internalize in HER2-overexpressing breast cancer cells, enabling potent anti-tumor activity. To overcome the problems associated with the short half-lives of this drug delivery system, we have constructed PE38KDEL-loaded anti-HER2 PEGylated liposomes (PE-HER-liposomes). PE-HER-liposomes were constructed with Fab′ of recombinant humanized anti-HER2 monoclonal antibody (anti-HER2 Fab′) covalently linked to PEGylated liposomes containing PE38KDEL (PE-liposomes). We attached anti-HER2 Fab′ to the terminus of PEG (polyethylene glycol) on PEGylated liposomes. Incorporation of pyridylthiopropionoylamino-PEG-distearoylphosphatidylethanolamine (PDP-PEG-DSPE) into PEGylated liposomes followed by mild thiolysis of the PDP groups resulted in the formation of reactive thiol groups at the periphery of the liposomes. Efficient attachment of maleimide-derivatized anti-HER2 Fab′ took place under mild conditions. The characterization of PE-HER-liposomes, such as particle size, was evaluated by dynamic light-scattering detector. The Micro BCA method was used to determine the encapsulation efficiency of PE38KDEL and the quantity of conjugated Fab′. Flow cytometry and confocal microscopy showed that PE-HER-liposomes possessed receptor-specific binding and internalization for HER2-overexpressing SK-BR3 cells. Remarkably, PE-HER-liposomes were more cytotoxic than non-targeted PE-liposomes in HER2-overexpressing breast cancer cells. In conclusion, PE-HER-liposomes could serve as a promising therapeutic candidate for the treatment of HER2-overexpressing breast cancers.