Abstract 5452: Pimozide suppresses the growth of brain tumor by targeting oncogenic pathways

Abstract

Abstract Brain tumor is considered as one of the most aggressive and incurable form of cancer. Majority of the brain tumors have a median survival rate of only 12%. Even though advanced treatments such as surgical removal, chemotherapy and radiotherapy are available, brain tumor persists to be lethal. Obstacles associated with the current treatment options are: recurrence, development of resistance and inability to cross blood brain barrier (BBB). BBB restricts majority of drugs to reach the brain thus resulting in an ineffective treatment. Pimozide (PMZ) is an antipsychotic drug used for the treatment of schizophrenia and chronic psychosis. In this study, pimozide has shown significant reduction in the viability of U-87MG, U-251MG, DAOY and T98G cell lines with an IC50 ranging from 11µM to 20µM after 24 h of treatment. Pimozide induced apoptosis in these cell lines as evaluated by FITC/Annexin assay and further validated by the cleavage of caspase 3 as well as PARP by western blot analysis. Pimozide treatment resulted in the concentration dependent decrease in the expression of GLI1, OCT4, SOX2 and NANOG in U87MG, U251MG, DAOY and T98G brain cancer cell lines, depicting a reduction in the stem cell like property of these cell lines. In addition, pimozide treatment inhibited the expression of proto-oncogene c-Myc. Inhibition of Gli1 and c-Myc demonstrates that pimozide might also inhibit the growth of cancer cells by targeting SHH signaling. Our results further demonstrated that oral administration of pimozide (25mg/kg) inhibits the brain tumors in intracranial tumor model with no significant difference in average weight of critical organs. It is important to note that pimozide is an FDA approved drug with no considerable toxicity. Overall, this study depicts that pimizode is a potential candidate to target brain tumors. Citation Format: Itishree Kaushik, Alok Ranjan, Blake Schwettmann, Sanjay Srivastava. Pimozide suppresses the growth of brain tumor by targeting oncogenic pathways [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5452.