Exth-65. identification of lomerizine as a potential anti-glioblastoma drug

Abstract BACKGROUND Glioblastoma (GBM) is one of the most malignant primary brain tumors. Despite development of surgical techniques, chemotherapy and radiotherapy, GBM prognosis is still poor. Here, we identified lomerizine, a prophylactic drug for migraine, as a potential anti-GBM drug from thousands of existing compounds. We investigated its therapeutic effects both in vitro and in vivo with the purpose of drug repositioning. Materials and method: Human patient-derived glioma stem cell line (GSC; KGS01, KGS10, KGS15), their differentiated cells, and GBM cell lines (A172, SNB19, T98, U87) were used. Proliferation assay, migration assay and invasion assay were performed with all cell lines. Sphere-forming assay was performed with GSCs. Various signaling pathways altered by lomerizine were analyzed by Western blotting. In addition, induction of apoptosis was evaluated by immunofluorescence and Annexin V assay. Anti-GBM effects of lomerizine in vivo was validated with a mouse brain tumor model. Result: Lomerizine inhibited proliferation, migration, and invasion dose-dependently in all cell lines, especially in GSCs. Sphere formation was also suppressed by lomerizine in all GSCs. STAT3, which is involved in tumorigenesis, was dephosphorylated after the treatment with lomerizine in a dose-dependent manner in all cell lines. Furthermore, apoptosis induction by lomerizine was confirmed in both immunofluorescence and Annexin V assay. In vivo experiments showed a significant tumor suppression and prolongation of overall survival in the group of mice treated with lomerizine. CONCLUSION This study suggests that lomerizine has anti- GBM effects.