Aurora A kinase inhibition enhances oncolytic herpes virotherapy through cytotoxic synergy and innate cellular immune modulation

// Mark A. Currier 1 , Les Sprague 1 , Tilat A. Rizvi 2 , Brooke Nartker 1 , Chun-Yu Chen 1 , Pin-Yi Wang 1 , Brian J. Hutzen 1 , Meghan R. Franczek 1 , Ami V. Patel 2 , Katherine E. Chaney 2 , Keri A. Streby 1,3 , Jeffrey A. Ecsedy 4 , Joe Conner 5 , Nancy Ratner 2 and Timothy P. Cripe 1,3 1 Center for Childhood Cancer and Blood Diseases, Nationwide Children’s Hospital, The Ohio State University, Columbus, Ohio, USA 2 Division of Experimental Hematology and Cancer Biology, Cincinnati Children’s Hospital Medical Center; Cincinnati, Ohio, USA 3 Division of Hematology/Oncology/Blood and Marrow Transplantation, Nationwide Children’s Hospital, The Ohio State University, Columbus, Ohio, USA 4 Takeda Pharmaceuticals International Co, Cambridge, MA, USA 5 Virttu Biologics, Ltd, Biocity, Scotland, Newhouse, United Kingdom Correspondence to: Timothy P. Cripe, email: // Keywords : oHSV, Aurora A kinase, neuroblastoma, MPNST Received : November 07, 2016 Accepted : January 17, 2017 Published : February 02, 2017 Abstract Malignant peripheral nerve sheath tumor (MPNST) and neuroblastoma models respond to the investigational small molecule Aurora A kinase inhibitor, alisertib. We previously reported that MPNST and neuroblastomas are also susceptible to oncolytic herpes virus (oHSV) therapy. Herein, we show that combination of alisertib and HSV1716, a virus derived from HSV-1 and attenuated by deletion of RL1, exhibits significantly increased antitumor efficacy compared to either monotherapy. Alisertib and HSV1716 reduced tumor growth and increased survival in two xenograft models of MPNST and neuroblastoma. We found the enhanced antitumor effect was due to multiple mechanisms that likely each contribute to the combination effect. First, oncolytic herpes virus increased the sensitivity of uninfected cells to alisertib cytotoxicity, a process we term virus-induced therapeutic adjuvant (VITA). Second, alisertib increased peak virus production and slowed virus clearance from tumors, both likely a consequence of it preventing virus-mediated increase of intratumoral NK cells. We also found that alisertib inhibited virus-induced accumulation of intratumoral myeloid derived suppressor cells, which normally are protumorigenic. Our data suggest that clinical trials of the combination of oHSV and alisertib are warranted in patients with neuroblastoma or MPNST.