Enhancement of the pro-apoptotic properties of Newcastle disease virus promotes tumor remission in syngeneic murine cancer models

摘要

Newcastle disease virus (NDV) is considered a promising agent for cancer therapy due to its oncolytic properties. These include preferential replication in transformed cells, induction of innate and adaptive immune responses within tumors and cytopathic effects in infected tumor cells due to the activation of apoptosis. In order to enhance the latter and thus possibly enhance the overall oncolytic activity of NDV, we generated a recombinant NDV encoding the human TNF receptor Fas (rNDV-B1/Fas). rNDV-B1/Fas replicates to similar titers as its wild type (rNDV-B1) counterpart, however overexpression of Fas in infected cells leads to higher levels of cytotoxicity correlated with faster and increased apoptosis responses in which both the intrinsic and extrinsic pathways are activated earlier. Furthermore, in vivo studies in syngeneic murine melanoma model show an enhancement of the oncolytic properties of rNDV-B1/Fas, with major improvements in survival and tumor remission. Altogether, our data suggest that up-regulation of the pro-apoptotic function of NDV is a viable approach to enhance its anti-tumor properties, and adds to the currently known, rationally-based strategies to design optimized therapeutic viral vectors for the treatment of cancer.