Gene delivery to hypoxic cells in vitro

• Published in: British journal of cancer Vol. 83; no. 5; pp. 662 - 667
• Main Authors: DACHS, G. U, CORALLI, C, HART, S. L, TOZER, G. M
• Format: Journal Article
• Language: English
• Published: Basingstoke Nature Publishing Group 01-09-2000
• Subjects: Animals; Biological and medical sciences; Cancer research; Cancer therapies; Cell growth; Cell Line; Cell Separation; Cytomegalovirus; Feasibility Studies; Flow Cytometry; Gene expression; Gene therapy; Gene Transfer Techniques; Genetic Therapy - methods; Genetic Vectors; Humans; Hypoxia; Medical research; Medical sciences; Mice; Other treatments; Oxygen - metabolism; Peptides; Peptides - genetics; Phosphatidylethanolamines - genetics; Plasmids - genetics; Promoter Regions, Genetic; Proteins; Radiation; Regular; Time Factors; Transfection; Treatment. General aspects; Tumor Cells, Cultured; Tumors; United Kingdom > UK; Antineoplastic agent; Human; Cell culture; Evaluation; Solid tumor; Correlation; Prognosis; Treatment efficiency; Experimental study; Gene expression; Radiotherapy; Genetic transfer; Chemotherapy; Hypoxemia; Gene therapy; Negative therapeutic reaction; Tumor cell
• ISSN: 0007-0920; 1532-1827
• DOI: 10.1054/bjoc.2000.1318

Hypoxia in solid tumours has been correlated with poor prognosis and resistance to radiation and chemotherapy. Hypoxia is also a strong stimulus for gene expression. We previously proposed a gene therapy approach which exploits the presence of severe hypoxia in tumours for the induction of therapeutic genes. Hypoxic cells are known to have a reduced metabolic rate, transcription and translation. These facts may prevent gene transfer and therefore warranted further investigation. In this paper the feasibility of gene delivery in vitro under tumour conditions was demonstrated. DNA was delivered in vitro using a peptide-mediated non-viral system. Across a range of oxygen tensions and mammalian cell lines (including human tumour and endothelial cells) it was shown that hypoxic cells could be transfected. Transfection efficiencies varied depending on the level of hypoxia, cell characteristics and gene promoters used. An in vitro model of hypoxia/reoxygenation, designed to mimic the variable nature of tumour hypoxia, showed that hypoxic preconditioning and reoxygenation alone did not reduce transfection efficiency significantly; only chronic anoxia reduced transfection. The fact that neither intermediate hypoxia nor intermittent anoxia significantly reduced transfection is promising for future hypoxia-targeted gene therapy strategies.