Gene delivery using a receptor-mediated gene transfer system targeted to hepatocellular carcinoma cells

Abstract

For gene therapy to be effective in cancers, it is necessary to deliver therapeutic genes into cells with high specificity and efficiency. In this study, we examined the in vitro and in vivo gene delivery efficiency of a new, growth receptor-mediated gene transfer system in hepatocellular carcinoma (HCC). The effects of transfection of wild-type p53 using this system were also studied. The system consisted of a ligand oligopeptide for epidermal growth factor receptor (EGFR) recognition, a polypeptide for DNA binding, and an endosome-releasing oligopeptide for endosomolysis. Two human HCC cell lines and a normal liver cell line were used, and pCMV-␤-galactosidase (␤-gal) was used as a reporter gene. Both HCC cell lines had strong expression of EGFR and the in vitro transfer efficiency peaked at day 5 at about 50%. This finding was in contrast to the normal liver cell line, which had weak EGFR expression and less than 1% transfer efficiency throughout. For in vivo gene transfer in tumors produced by inoculating HCC cells in nude mice and with the vector-␤-gal gene complex injected peritumorally, ␤-gal expression was detected within the tumors at 12 hr, peaked at day 5 involving about 50% of the tumor cells and persisted at 2 weeks. Using this vector system, transfection of wild-type p53 into Huh-7 cells that had mutated p53 resulted in significant growth inhibition of cancer cells accompanied by a decreased G2/M phase and increased p53 protein. In conclusion, this receptor-mediated gene transfer system appears to work specifically in HCC cells with high efficiency, and may be promising in delivering apoptotic and other genes into HCC cells.

The mechanism of selective transfection mediated by pentablock copolymers; Part I: Investigation of cellular uptake

“…Overcoming a single barrier cannot necessarily guarantee the success of transfection. As reported for PLL-based vectors, gene delivery through EGF receptor-mediated internalization was inefficient without the aid of endosome-releasing agents [10,35,37], implying that the ligand and endosomolytic agents together play an essential role in PLL-mediated gene delivery. However, for vectors composed of PEI with great advantage in escaping the endosome, the incorporated EGF could make an independent contribution on increasing transfection efficiency [5,6].…”

“…In Part I, this study investigates whether cellular entry is one of the main intracellular barriers to transfection in the pentablock copolymer vector systems by incorporating epidermal growth factor (EGF), a 53-residue peptide that binds to the EGF receptor with high affinity [4], into the polyplex constructs in different ways, with the aim of enhancing transfection in cancer cell lines through receptor-mediated cellular uptake. A number of studies have shown the efficacy of EGF incorporation in enhancing transfection efficiency of some polymeric vectors in tumor cells that overexpress the EGF-receptor [5][6][7][8][9][10][11].…”

Apoptotic and anti-angiogenic strategies in liver and gastrointestinal malignancies

“…Furthermore, axin, an important regulator of b-catenin, is commonly mutated in human HCCs, and transduction of the wild-type Axin gene (AXIN1) induces apoptosis in HCC cells as well as in colon cancer cells. Other gene therapy possibilities against cancer have been reported by administration of a recombinant adenoviral vector expressing wild-type tumor suppressor p53 gene [58].…”

Gene Therapy in Liver Diseases: State-of-the-Art and Future Perspectives

“…Towards this target, several approaches have been made [164][165][166][167][168][169]. Herpes virus simplex type-1 (HSV-1) is one of the most promising viral platforms for transferring therapeutic genes and the development of oncolytic vectors that can target, multiply in, and eradicate hepatoma cells via their lytic cycle.…”