Oncolytic viruses: how “lytic” must they be for therapeutic efficacy?

Abstract

Oncolytic viruses (OVs) preferentially target and kill cancer cells without affecting healthy cells through a multi-modal mechanism of action. While historically the direct killing activity of OVs was considered the primary mode of action, initiation or augmentation of a host antitumor immune response is now considered an essential aspect of oncolytic virotherapy. To improve oncolytic virotherapy, many studies focus on increasing virus replication and spread. In this article, we open for discussion the traditional dogma that correlates replication with the efficacy of OVs, pointing out several examples that oppose this principle.

Keywords

• oncolytic virus
• oncolysis
• antitumor immune response
• immunotherapy
• productive infection
• herpes simplex virus
• vaccinia virus
• reovirus
• vesicular stomatitis virus
• newcastle disease virus