Enhanced gene transfer and cell death following p53 gene transfer using photochemical internalisation of glucosylated PEI-DNA complexes

J Gene Med. 2004 Aug;6(8):884-94. doi: 10.1002/jgm.573.


Background: p53 is frequently mutated in many cancers including human head and neck squamous cell carcinoma and pancreatic cancer. In tumor models, wild-type (wt) p53 gene transfer induces apoptosis and tumor regression in vivo, justifying the extensive clinical investigation of p53 gene therapy.

Methods: p53 nonviral-mediated gene transfer was achieved using glucosylated polyethylenimine (PEI) in conjunction with photochemical internalisation (PCI). Experimental conditions were optimised using the green fluorescent protein (GFP) as a reporter. p53 gene transfer was then evaluated using semi-quantitative RT-PCR in p53-deleted PANC3 and p53-mutated FaDu cell lines. Following gene transfer, induction of apoptosis was investigated using phosphatidylserine externalisation and nuclear fragmentation assays. Induction of long-term cell death was analysed using colony-forming assays.

Results: PCI was found to enhance GFP gene transfer after 48 h in both cell lines. Whether using glucosylated-PEI alone or associated with PCI, p53 gene transfer was achieved with subsequent recovery of p53 mRNA expression in PANC3 cells and a significant 4-fold increase in p53 mRNA expression in FaDu cells. PCI was found to further enhance p53 mRNA expression by 2.3-fold in PANC3 cells. Spontaneous induction of apoptosis following wt-p53 gene transfer was achieved in both cell lines. PCI was found to enhance apoptosis up to levels similar to those achieved with chemotherapy. As a consequence, long-term cell death was significantly enhanced after wt-p53 gene transfer when PCI was used in both cell lines, yielding up to 60% cell death.

Conclusions: PCI increases glucosylated-PEI-mediated p53 gene transfer, apoptosis as well as cell death in mutant p53 human cancer cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis*
  • DNA Fragmentation
  • Gene Transfer Techniques*
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Humans
  • Immunohistochemistry
  • Indicators and Reagents / chemistry
  • Microscopy, Fluorescence
  • Photochemistry
  • Plasmids
  • Polyethyleneimine / analogs & derivatives*
  • RNA, Messenger / metabolism
  • Tumor Cells, Cultured
  • Tumor Stem Cell Assay / methods
  • Tumor Suppressor Protein p53 / genetics*


  • Indicators and Reagents
  • RNA, Messenger
  • Tumor Suppressor Protein p53
  • Green Fluorescent Proteins
  • Polyethyleneimine