Gujar et al. briefly review and graphically illustrate the oncolytic virus approach to cancer immunotherapy, describing its mechanisms of action (oncolysis, transgene expression, tumor vasculature collapse, and stimulation of antitumor immunity via induction of cytokines and chemokines), outlining the resulting innate and adaptive immune responses, and describing barriers and potential solutions to improving use.
Oncolytic viruses (OVs) preferentially infect and kill cancer cells without harming normal cells. OVs can revert cancer-associated immune suppression and initiate clinically meaningful antitumor immune responses. OVs and their resultant immunological events can act at both primary and metastatic sites. Thus, OVs can be exploited for cancer gene therapies and immunotherapies alone or in combination with other interventions, including immune checkpoint blockade.