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Human
glioma cells transformed by IGF-I triple helix technology show immune and
apoptotic characteristics determining cell selection for gene therapy of
glioblastoma
Ly A, Duc HT, Kalamarides M, Trojan LA, Pan Y, Shevelev A, Francois JC, Noel
T, Kane A, Henin D, Anthony DD, Trojan J
Laboratory of Developmental Neurology, INSERM and University
Paris VII, Hopital Robert Debre, 75019 Paris, France
Aims. Insulin-like growth factor type I (IGF-I) antisense cellular gene
therapy of tumours is based on the following data: rat glioma or hepatoma cells
transfected with the vector encoding IGF-I antisense cDNA lose their
tumorigenicity and induce a tumour specific immune response involving CD8(+) T
cells.
Recently, using the IGF-I triple helix approach in studies of tumorigenicity,
major histocompatibility complex class I (MHC-I) antigens were demonstrated in
rat glioma transfected cells.
This study used comparative IGF-I antisense and triple helix technologies in
human primary glioma cells to determine the triple helix strategy that would be
most appropriate for the treatment of glioblastoma.
Methods.
The cells were transfected using the IGF-I triple helix expression vector,
pMT-AG, derived from the pMT-EP vector.
pMT-AG contains a cassette comprising a 23 bp DNA fragment transcribing a third
RNA strand, which forms a triple helix structure within a target region of the
human IGF-I gene.
Using pMT-EP, vectors encoding MHC-I or B7 antisense cDNA were also
constructed.
Results.
IGF-I triple helix transfected glioma cells are characterised by immune and
apoptotic phenomena that appear to be related.
The expression of MHC-I and B7 in transfected cells (analysed by flow cytometry)
was accompanied by programmed cell death (detected by dUTP fluorescein terminal
transferase labelling of nicked DNA and electron microscopic techniques).
Cotransfection of these cells with MHC-I and B7 antisense vectors suppressed the
expression of MHC-I and B7, and was associated with a pronounced decrease in
apoptosis.
Conclusion.
When designing an IGF-I triple helix strategy for the treatment of human
glioblastoma, the transfected tumour cells should have the following
characteristics: the absence of IGF-I, the presence of both MHC-I and B7
molecules, and signs of apoptosis.
PMID: 11477137 [PubMed - indexed for MEDLINE]
Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11477137&dopt=Abstract
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