We hypothesize that redirection of Delta 24 infectivity to mutant EGFR would end result from the focusing on in the cancer cells liable for the superior neoplastic phenotype of gliomas. Implementing isogenic cell lines, we 1st confirmed the peptide PEPCH1 binds preferentially to your membrane of cells overexpress ing EGFRvIII. Then we constructed an adenovirus with retargeted infectivity via EGFR by inserting the PEPCH1 coding sequence during the HI loop of the Delta 24 detar geted adenovirus. Delta 24 RIVER infected and rep licated efficiently in EGFR expressing order b-AP15 A549 cells, permitting for adenoviral manufacturing. Importantly, Delta 24 RIVER showed selective cytotoxicity in cancer cells expressing high levels of EGFR. Therefore, infection with very similar doses of Delta 24 RIVER induced a cytopathic impact in A549 cells but not in 293 cells.
We evaluated the EGFR expression level in numerous cancer cell lines and typical cells, like MDA MB 468 breast cancer cells, A549 non tiny cell lung cancer cells, MRC five human lung fibroblasts, U2OS and Saos 2 sarcoma cells, and ordinary human astro cytes. MDA YM201636 MB 468 and A549 cells showed large EGFR expression ranges. Conversely, U2OS, Saos 2, and MRC five had been characterized by reduced EGFR expression. We observed that Delta 24 RIVER acquired a replication pheno style, as assessed by expression of late genes, and induced important cytolysis within a dose dependent manner in cancer cells with high ranges of EGFR but didn’t replicate in regular fibroblasts and astrocytes. To more prove the EGFR dependent infectivity and cytolysis on the Delta 24 RIVER construct, we tested Delta 24 RIVER and Delta 24 within the U87 MG isogenic procedure. Delta 24 RIVER induced potent cytolysis while in the U87 Delta EGFR cell line but not inside the U87 parental line.
In vivo experiments making use of U87MG and U87 Delta EGFR

xenografts implanted in nude mice treated intratu morally with a dose of 10e8 pfu/animal of Delta 24 RIVER are in progress. Taken together, these data constitute proof of principle to the direct target of a cancer specific receptor employing replication competent tumor selective adenoviruses. ET 29. TARGETED CANCER GENE THERAPY Implementing AN HIF DEPENDENT ONCOLYTIC ADENOVIRUS Dawn E. Post,1,2,6 Eric M. Sandberg,1,2 Narra Sarojini Devi,one,2 Daniel J. Brat,4,6 Zhiheng Xu,5,6 Mourad Tighiouart,5,6 and Erwin G. Van Meir1,2,3,6, 1Laboratory of Molecular Neuro Oncology, Departments of 2 Neurosurgery, 3Hematology/Oncology and 4Pathology, 5Biostatistics Research and Informatics, 6Winship Cancer Institute, Emory University, Atlanta, GA, USA There are no approved therapies for hypoxic/HIF active tumor cells, which are associated with tumor resistance to therapy, and have therefore become an important therapeutic target. The mutant variant III of EGFR constitutes the prototype within the cancer specific receptor.