Tat-conjugated synthetic macromolecules facilitate cytoplasmic drug delivery to human ovarian carcinoma cells.
We have synthesized N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-cell penetrating peptide Tat conjugates and evaluated their subcellular distribution in A2780 human ovarian carcinoma cells by confocal fluorescence microscopy and subcellular fractionation. Our data indicate the transport of these conjugates by a single Tat molecule to both the cytoplasm and nucleus via a nonendocytotic and concentration independent process. The uptake was observed to occur within 3 min, as confirmed by live cell microscopy. In contrast, HPMA copolymers lacking the Tat peptide were internalized solely by endocytosis. For the first time, Tat-mediated cytoplasmic delivery of a polymer bound anticancer drug, doxorubicin, was also demonstrated. These findings establish the feasibility of overcoming major cellular and subcellular obstacles to intracellular macromolecular delivery and hold great promise for the development of polymer-based systems for the cytoplasmic delivery of therapeutic molecules.
Nori
Aparna
A
Department of Pharmaceutics, University of Utah, Salt Lake City, Utah 84112, USA.
Jensen
Keith D
KD
Tijerina
Monica
M
Kopecková
Pavla
P
Kopecek
Jindrich
J
D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004337:Drug Carriers / Q000737:chemistry* / Q000493:pharmacokinetics; D005260:Female; D015696:Gene Products, tat / Q000737:chemistry* / Q000493:pharmacokinetics; D006801:Humans; D008689:Methacrylates; D008856:Microscopy, Fluorescence; D010051:Ovarian Neoplasms / Q000473:pathology*; D011108:Polymers / Q000737:chemistry* / Q000493:pharmacokinetics; D022161:Transport Vesicles / Q000378:metabolism; D014407:Tumor Cells, Cultured
D004337:Drug Carriers; D015696:Gene Products, tat; D008689:Methacrylates; D011108:Polymers; C032802:hydroxypropyl methacrylate