Photochemical internalization-mediated nonviral gene transfection: polyamine core-shell nanoparticles as gene carrier

The overall objective of the research was to investigate the utility of photochemical internalization (PCI) for the enhanced nonviral transfection of genes into glioma cells. The PCI-mediated introduction of the tumor suppressor gene phosphatase and tensin homolog (PTEN) or the cytosine deaminase (CD) pro-drug activating gene into U87 or U251 glioma cell monolayers and multicell tumor spheroids were evaluated. In the study reported here, polyamine-DNA gene polyplexes were encapsulated in a nanoparticle (NP) with an acid degradable polyketal outer shell. These NP synthetically mimic the roles of viral capsid and envelope, which transport and release the gene, respectively. The effects of PCI-mediated suppressor and suicide genes trans- fection efficiency employing either "naked" polyplex cores alone or as NP-shelled cores were compared. PCI was performed with the photosensitizer AlPcS2a and λ ¼ 670-nm laser irradiance. The results clearly dem- onstrated that the PCI can enhance the delivery of both the PTEN or CD genes in human glioma cell mono- layers and multicell tumor spheroids. The transfection efficiency, as measured by cell survival and inhibition of spheroid growth, was found to be significantly greater at suboptimal light and DNA levels for shelled NPs compared with polyamine-DNA polyplexes alone. © 2014 Society of Photo-Optical Instrumentation Engineers (SPIE) (DOI: 10