Enhanced gene transfection by photochemical internalization of protomine sulfate/DNA complexes

Publication Type:

Conference Paper


SPIE BiOSPhotonic Therapeutics and Diagnostics VIII, SPIE, Volume 8207, San Francisco, California, p.82074S - 82074S-8 (2012)


Introduction: One of many limitations for cancer gene therapy is the inability of the therapeutic gene to transfect a sufficient number of tumor cells. Photochemical internalization (PCI) is a photodynamic therapy-based approach for improving the delivery of macromolecules and genes into the cell cytosol. The utility of PCI for the delivery of the GFP indicator gene on the same plasmid as a tumor suppressor gene (PTEN) was investigated in monolayers of U251 human glioma cells. Materials and Methods: U251 monolayers were incubated in AlPcS2a for 18 h. The monolayers were incubated with non-viral vectors for either 4 or 18 hrs. In all cases, light treatment was performed with a diode laser at a wavelength of 670 nm. The non-viral transfection agents, branched PEI or protomine sulfate (PS), were used with the plasmid construct (GFP-PTEN). Results: PS was much less toxic to the gliomas cells compared to BPEI but was highly inefficient at gene transfection. PCI resulted in a 5-10 fold increase in GFP protein expression compared to controls. Conclusions: Collectively, the results suggest that AlPcS2a-mediated PCI can be used to enhance transfection of tumor suppressor genes in glioma cells.