New characteristics of cancer immunotherapy: trends in viral tumor immunotherapy with influenza virus-based approaches

Immunomodulatory cancer therapy is witnessing the rise of viral immunotherapy. The oncolytic influenza A virus, although promising in preclinical investigations, remains to be implemented in clinical practice. Recent progress in genetic engineering, coupled with experiential insights, offers opportunities to enhance the therapeutic efficacy of the influenza A virus. This review explores the use of the influenza virus, its attenuated forms, and associated vaccines in cancer immunotherapy, highlighting their respective advantages and challenges. We further elucidate methods for engineering influenza viruses and innovative approaches to augment them with cytokines or immune checkpoint inhibitors, aiming to maximize their clinical impact. Our goal is to provide insights essential for refining influenza A virus-based viral tumor immunotherapies.