EDL-291, a novel isoquinoline, presents antiglioblastoma effects in vitro and in vivo

: To investigate the effectiveness of EDL-291, a 6,7-dimethoxy-1-[4-(4-methoxypyridin-3-yl)benzyl]-1,2,3,4-tetrahydroisoquinoline dihydrochloride compound, in inhibiting the survival of glioblastoma in vitro and in vivo. Dose-response curves were generated to determine the EC50 in rat and human glioblastoma cell lines by treatment with different dilutions of EDL-291. To evaluate the architecture of the glioblastoma cells after treatment with EDL-291, the rat and human glioblastoma cells were stained with Mito Tracker Green FM. To determine whether autophagy was induced in EDL-291-treated glioblastoma cells, both rat and human glioblastoma cell lines were stained with acridine orange and light chain-3 immunoblots were performed. The efficacy of EDL-291 was monitored in vivo using a rat glioblastoma model. Rat glioblastoma cells were transplanted into an intracranial rat model, followed by infusions of saline, a low dose of EDL-291 (20 mg/kg for the first half hour, followed by 40 mg/kg EDL-291 in saline for 4 h), or a high dose of EDL-291 (60 mg/kg for the first half hour, followed by 90 mg/kg EDL-291 for 4 h). EDL-291 inhibits glioblastoma in vitro by destroying the mitochondria as shown with Mito Tracker Green FM. Acridine orange staining and light chain-3 immunoblots suggest that autophagy is induced when glioblastoma cells are treated with EDL-291. In vivo, a low dosage of EDL-291 is sufficient and effective in reducing glioblastoma tumor size. EDL-291 selectively induces cell death in rat and human glioblastoma cell lines by the induction of autophagy. EDL-291 exhibits antiglioblastoma effects both in vitro and in vivo.