Abstract 3200: New epigenetic mechanism of disulfiram targeting chromatin remodeling in neuroblastoma

Abstract Pediatric neuroblastoma is one of the most common extra cranial cancers in children. Despite an improvement in survival with the currently available therapies, neuroblastoma with an amplification of the transcription factor MYCN have a very poor prognosis. New therapeutic approaches must be developed to increase the survival of patients. One such approach is epigenetic drug therapy. Neuroblastoma, like many other pediatric cancers, contains several epigenetic alterations at the level of DNA methylation and histone modifications. In a screening of FDA approved drugs, we discovered some molecules having characteristics of epigenetic drugs that were unknown until now. Our study seeks to demonstrate the efficacy of these molecules in the treatment of neuroblastoma cell lines. Following preliminary tests, one of the molecules approved by the FDA stood out: disulfiram, a medication approved for the treatment of chronic alcoholism. We treated neuroblastoma cell lines (MYCN amplified: IMR-32, N91 and SK-N-DZ; MYCN non-amplified: SK-N-AS and SK-N-SH) for 48 hours with disulfiram at clinically relevant concentrations (from 10 nM to 50 μM). Our results demonstrate a 50% growth inhibition (IC50) of 50nM for the cell lines tested. In addition, after analysis by flow cytometry, we found a cell cycle block in G2/M. We also observed a decrease in the transcription factor MYCN and a reduction in acetylation of several histone marks by Western blots analysis. Further studies are underway to determine the mechanism of action of disulfiram and we also plan on doing RNA sequencing and ChIP sequencing. This study will evaluate the efficacy of disulfiram alone as well as in combination with other epigenetic drugs, such as DNA methyltransferase inhibitor decitabine, for the treatment of neuroblastoma. Citation Format: Simon Jacques-Ricard, Noel Raynal, Gregory Armaos, Elodie Da Costa, Annie Beaudry. New epigenetic mechanism of disulfiram targeting chromatin remodeling in neuroblastoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3200.