Oncolytic Adenovirus Programmed By Synthetic Gene Circuit for Cancer Immunotherapy

Improving efficacy of oncolytic virotherapy remains challenging due to difficulty to increase specificity and immune responses against cancer and limited understanding of its population dynamics. Here, we constructed programmable and modular synthetic gene circuits to control adenoviral replication and release of immune effectors selectively in hepatocellular carcinoma cells in response to multiple promoter and microRNA inputs. By performing computational simulations and mouse model experiments, we found that replicable adenovirus has a superior tumor-killing efficacy than non-replicable adenovirus. We observed a synergistic effect on promoting local lymphocyte cytotoxicity and systematic vaccination in immunocompetent mouse models by combining tumor lysis and secretion of immunomodulators. Furthermore, our computational simulations showed that oncolytic virus that encodes immunomodulators can exert a more robust therapeutic efficacy than combinatorial treatment with oncolytic virus and immune effector. Our results provide a novel strategy to engineer oncolytic adenovirus, which may lead to innovative immunotherapies for a variety of cancers.