Enhanced laser thermal ablation for the in vitro treatment of liver cancer by specific delivery of multiwalled carbon nanotubes functionalized with human serum albumin

Abstract

Cornel Iancu1, Lucian Mocan1, Constantin Bele2, Anamaria Ioana Orza2, Flaviu A Tabaran3, Cornel Catoi3, Rares Stiufiuc4, Ariana Stir1, Cristian Matea2, Dana Iancu1, Lucia Agoston-Coldea1, Florin Zaharie1, Teodora Mocan11Department of Nanomedicine, 'Iuliu Hatieganu' University of Medicine and Pharmacy, Third Surgery Clinic, Cluj-Napoca, Romania; 2Department of Biochemistry, 3Department of Pathology, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania; 4Department of Biophysics, 'Iuliu Hatieganu' University of Medicine and Pharmacy, Cluj-Napoca, RomaniaAbstract: The main goal of this investigation was to develop and test a new method of treatment for human hepatocellular carcinoma (HCC). We present a method of carbon nanotube-enhanced laser thermal ablation of HepG2 cells (human hepatocellular liver carcinoma cell line) based on a simple multiwalled carbon nanotube (MWCNT) carrier system, such as human serum albumin (HSA), and demonstrate its selective therapeutic efficacy compared with normal hepatocyte cells. Both HepG2 cells and hepatocytes were treated with HSA–MWCNTs at various concentrations and at various incubation times and further irradiated using a 2 W, 808 nm laser beam. Transmission electron, phase contrast, and confocal microscopy combined with immunochemical staining were used to demonstrate the selective internalization of HSA–MWCNTs via Gp60 receptors and the caveolin-mediated endocytosis inside HepG2 cells. The postirradiation apoptotic rate of HepG2 cells treated with HSA–MWCNTs ranged from 88.24% (for 50 mg/L) at 60 sec to 92.34% (for 50 mg/L) at 30 min. Significantly lower necrotic rates were obtained when human hepatocytes were treated with HSA–MWCNTs in a similar manner. Our results clearly show that HSA–MWCNTs selectively attach on the albondin (aka Gp60) receptor located on the HepG2 membrane, followed by an uptake through a caveolin-dependent endocytosis process. These unique results may represent a major step in liver cancer treatment using nanolocalized thermal ablation by laser heating.Keywords: carbon nanotubes, albumin, HepG2 cells, noncovalent functionalization, laser irradiation, Gp60 receptor