Antisense to the epstein-barr virus (EBV)-encoded latent membrane protein 1 (LMP-1) suppresses LMP-1 and bcl-2 expression and promotes apoptosis in EBV-immortalized B cells.
The Epstein-Barr virus (EBV)-encoded latent membrane protein (LMP-1) is required for viral transformation and functions to protect cells from apoptotic cell death, in part, by induction of antiapoptotic genes, including Bcl-2 and A20. We have used antisense oligodeoxynucleotides targeted to LMP-1 as a strategy to suppress LMP-1 expression and thereby inhibit its functions. We have shown that levels of LMP-1 protein in EBV-positive lymphoblastoid cell lines can be reduced by in vitro treatment with unmodified oligodeoxynucleotides targeted to the first five codons of the LMP-1 open-reading frame. Furthermore, suppression of LMP-1 was associated with molecular and phenotypic effects that included downregulation of the LMP-1-inducible antiapoptotic genes, Bcl-2 and Mcl-1, inhibition of proliferation, stimulation of apoptosis, and enhancement of sensitivity to the chemotherapeutic agent, etoposide. These effects were largely sequence-specific and observed in EBV-positive, but not EBV-negative cell lines. These studies suggest that lowering expression of LMP-1 in EBV-associated malignancy might have therapeutic effects and might synergize with other antitumor agents.
Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA.
J L
JL
Kenney
M E
ME
Guinness
T
T
Curiel
J
J
Lacy
D017209:Apoptosis / Q000235:genetics*; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D002461:Cell Line, Transformed; D003062:Codon; D005047:Etoposide / Q000494:pharmacology; D005312:Fetal Blood / Q000166:cytology; D015870:Gene Expression; D004854:Herpesvirus 4, Human / Q000235:genetics*; D064549:Myeloid Cell Leukemia Sequence 1 Protein; D009363:Neoplasm Proteins / Q000235:genetics; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D016366:Open Reading Frames; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D014763:Viral Matrix Proteins / Q000235:genetics*
D003062:Codon; C037662:EBV-associated membrane antigen, Epstein-Barr virus; D064549:Myeloid Cell Leukemia Sequence 1 Protein; D009363:Neoplasm Proteins; D016376:Oligonucleotides, Antisense; D019253:Proto-Oncogene Proteins c-bcl-2; D014763:Viral Matrix Proteins; D005047:Etoposide