A fiber chimeric CRAd vector Ad5/11-D24 double-armed with TRAIL and arresten for enhanced glioblastoma therapy

Malignant gliomas remain refractory to treatment despite advances in chemotherapy and surgical techniques. Conditionally replicating adenoviral vector (CRAd) could kill the tumor cells by selectively replicating in neoplastic cells, which represents a novel strategy for tumor therapy. Although CRAd with a 24-bp deletion in CR2 of the E1 region (CRAd5-D24) has been shown to have a better therapeutic effect over the other types of CRAd vectors, the current CRAd5-D24 still has some shortcomings for an efficient therapy of gliomas. In this study, we developed for the first time a novel vector CRAd5/11-D24.TRAIL/arresten by the following strategies: (1) modify CRAd5-D24 with Ad5/11 chimeric fiber to improve its infection efficiency for glioblastoma; and (2) insert two transgene expression cassettes into the E3 region and the region between the fiber and E4, respectively, for an enhanced therapeutic effect. The results indicated that the CRAd5/11-D24.TRAIL/arresten achieved nearly complete inhibition of glioma growth in nude mice possibly by increased antiangiogenesis and enhanced tumor apoptosis. The vector is the first reported E1A D24-deleted, Ad5/11 chimeric, and dual-armed oncolytic virus that shows markedly improved antitumor activities compared with the conventional oncolytic viruses. This novel antitumor agent should be evaluated further in future preclinical and clinical studies.