Evaluation of E1A double mutant oncolytic adenovectors in anti-glioma gene therapy.
Malignant glioma, in particular glioblastoma multiforme (GBM), represents one of the most devastating cancers currently known and existing treatment regimens do little to change patient prognosis. Conditionally replicating adenoviral vectors (CRAds) represent attractive experimental anti-cancer agents with potential for clinical application. However, early protein products of the wild type adenovirus backbone--such as E1A--limit CRAds' replicative specificity. In this study, we evaluated the oncolytic potency and specificity of CRAds in which p300/CPB and/or pRb binding capacities of E1A were ablated to reduce non-specific replicative cytolysis. In vitro cytopathic assays, quantitative PCR analysis, Western blot, and flow cytometry studies demonstrate the superior anti-glioma efficacy of a double-mutated CRAd, Ad2/24CMV, which harbors mutations that reduce E1A binding to p300/CPB and pRb. When compared to its single-mutated and wild type counterparts, Ad2/24CMV demonstrated attenuated replication and cytotoxicity in representative normal human brain while displaying enhanced replicative cytotoxicity in malignant glioma. These results have implications for the development of double-mutated CRAd vectors for enhanced GBM therapy.
Ulasov
Ilya V
IV
The Brain Tumor Center, The University of Chicago, Chicago, Illinois 60637, USA.
Tyler
Matthew A
MA
Rivera
Angel A
AA
Nettlebeck
Dirk M
DM
Douglas
Joanne T
JT
Lesniak
Maciej S
MS
D000256:Adenoviridae / Q000235:genetics*; D017500:Adenovirus E1A Proteins / Q000235:genetics*; D002460:Cell Line; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D005910:Glioma / Q000628:therapy*; D006801:Humans; D009154:Mutation; D050130:Oncolytic Virotherapy / Q000379:methods*; D050504:Oncolytic Viruses / Q000502:physiology*; D014779:Virus Replication
D017500:Adenovirus E1A Proteins