Oncolytic Virotherapy: A New Paradigm in Cancer Immunotherapy

Abstract

Oncolytic viruses (OVs) are emerging as potential treatment options for cancer. Natural and genetically engineered viruses exhibit various antitumor mechanisms. OVs act by direct cytolysis, the potentiation of the immune system through antigen release, and the activation of inflammatory responses or indirectly by interference with different types of elements in the tumor microenvironment, modification of energy metabolism in tumor cells, and antiangiogenic action. The action of OVs is pleiotropic, and they show varied interactions with the host and tumor cells. An important impediment in oncolytic virotherapy is the journey of the virus into the tumor cells and the possibility of its binding to different biological and nonbiological vectors. OVs have been demonstrated to eliminate cancer cells that are resistant to standard treatments in many clinical trials for various cancers (melanoma, lung, and hepatic); however, there are several elements of resistance to the action of viruses per se. Therefore, it is necessary to evaluate the combination of OVs with other standard treatment modalities, such as chemotherapy, immunotherapy, targeted therapies, and cellular therapies, to increase the response rate. This review provides a comprehensive update on OVs, their use in oncolytic virotherapy, and the future prospects of this therapy alongside the standard therapies currently used in cancer treatment.

Current Landscape of Cancer Immunotherapy: Harnessing the Immune Arsenal to Overcome Immune Evasion

“…Although OVs have exhibited encouraging outcomes in clinical trials across different cancer types, overcoming resistance to their therapeutic effects remains a challenge. Integrating OVs with conventional treatments like chemotherapy, immunotherapy, targeted therapies, and cellular therapies is crucial for augmenting response rates [505]. Cellular vaccines, including DC therapy and CAR-T therapy, play a crucial role in enhancing anti-tumor immunity by harnessing remarkable abilities for antigen recognition, processing, presentation, and T-cell sensitization [506].…”

Advancing non-small cell lung cancer treatment: the power of combination immunotherapies

“…In addition to cytolysis, OVs potentiate the immune system by releasing antigens and activating inflammatory responses. Indirectly, OVs alter energy metabolism in tumor cells, modify the TME, and act as antiangiogenic agents ( 146 ). In this regard, the safety and efficacy of combining Teliso-V (telisotuzumab vedotin), an anti-c-MET-directed antibody–drug conjugate, with nivolumab was assessed in advanced NSCLC patients ( 147 ).…”

Targeted Suicide Gene Therapy with Retroviral Replicating Vectors for Experimental Canine Cancers

“…Oncolytic virotherapy has been attracting attention as a novel therapeutic option for human cancers [ 2 , 4 , 5 ]. Human clinical trials have been conducted of oncolytic viruses created from cytotoxic viruses, including adenovirus [ 6 ], herpes simplex virus [ 7 , 8 , 9 ], and reovirus [ 10 ].…”