Synthesis and Εvaluation of Αnticancer Αctivity in Cells of Novel Stoichiometric Pegylated Fullerene-Doxorubicin Conjugates
- 625 Downloads
To synthesize pegylated stoichiometrically and structurally well-defined conjugates of fullerene (C60) with doxorubicin (DOX) and investigate their antiproliferative effect against cancer cell lines.
Stoichiometric (1:1 and 1:2) pegylated conjugates of C60 with DOX were synthesized using the Prato reaction to create fulleropyrrolidines equipped with a carboxyl function for anchoring a polyethylene glycol (PEG) moiety and either a hydroxyl group for attaching one molecule of DOX or a terminal alkyne group for attaching two molecules of DOX through a click reaction. In both conjugates, the DOX moieties are held through a urethane-type bond. Drug release was studied in phosphate buffer (PBS, pH 7.4) and MCF-7 cancer cells lysate. The uptake of the conjugates by MCF-7 cancer cells and their intracellular localization were studied with fluorescence microscopy. The antiproliferative activity of the conjugates was investigated using the WST-1 test.
One or two DOX molecules were anchored on pegylated C60 particles to form DOX-C60-PEG conjugates. Drug liberation from the conjugates was significantly accelerated in the presence of tumor cell lysate compared to PBS. The conjugates could be internalized by MCF-7 cells. DOX from the conjugates exhibited much delayed, compared to free DOX, localization in the nucleus and antiproliferative activity.
Pegylated DOX-C60 conjugates (1:1) and (2:1) with well-defined structure were successfully synthesized and found to exhibit comparable, but with a delayed onset, antiproliferative activity with free DOX against MCF-7 cancer cells. The results obtained justify further investigation of the potential of these conjugates as anticancer nanomedicines.
KEY WORDSantiproliferative activity conjugates doxorubicin fullerenes nanoparticles
Flash Column Chromatography
amino-polyethylene glycol monomethyl ether
ACKNOWLEDGMENTS AND DISCLOSURES
We wish to thank Dr. N. Eilert, University of Leipsig, for guidance regarding the preliminary biological results, Dr. G. Tsivgoulis, and Dr. K. Andriopoulou, Department of Chemistry, University of Patras, for UV/vis spectra and TGA measurements and related comments, respectively.
- 13.Hirsch A, Brettreich M. In Fullerenes: Chemistry and Reactions. Weinheim: Wiley VCH; 2005.Google Scholar
- 14.WST-1 proliferation assay at http://lifescience.roche.com/shop/products/cell-proliferation-reagent-wst-1.
- 20.Heymann D. Solubility of fullerenes C60 and C70 in water. Lunar and Planetary Science. 1996;27:543–4.Google Scholar