Targeting Myc and Hdac8 with a Combination of SiRNAs Inhibits Tumor Growth in a Murine Neuroblastoma Xenograft Model

Abstract

Neuroblastoma is a common tumor of the peripheral nervous system in children. Highly aggressive MYC-drivenneuroblastoma is defined by increased MYC and/or MYCN expression. HDAC8 overexpression is associated with advanced neuroblastoma. Previously, we have demonstrated that transient knockdown of both Myc and Hdac8 using siRNA significantly suppressed neuroblastoma cells proliferation compared to knockdown of either target in vitro. In this study, we further investigated whether combinational targeting Myc and Hdac8 in neuroblastoma xenograft mice model is consistent with our previous findings. Intratumoral treatment with siRNA-MYC and siRNA-HDAC8 reduced the levels of the target MYC protein by 64% and HDAC8 by 85%; in addition, we found that the average tumor growth was reduced by 80% compared to that of control tumors treated with NC-siRNA. Our results suggest the potential therapeutic effect of the combination of siRNA-MYC and siRNA-HDAC8 for neuroblastoma treatment.