Oncolytic viruses: advanced strategies in cancer therapy

Oncolytic viruses (OVs) represent a promising strategy in cancer immunotherapy, as they selectively infect and lyse tumor cells while simultaneously triggering robust antitumor immune responses. By inducing immunogenic cell death, OVs enhance tumor antigen presentation and initiate a systemic immune response, effectively transforming the tumor microenvironment from an immune-suppressive state to an immune-permissive state. In addition to exerting direct oncolytic effects, OVs modulate key tumor-associated biological processes, including tumor angiogenesis and extracellular matrix remodeling, disrupting tumor progression and metastasis. Notably, recent advances have highlighted the therapeutic potential of combining OVs with conventional and emerging cancer treatments, such as chemotherapy, radiotherapy, immune checkpoint inhibitors, adoptive cell therapy, and epigenetic-targeted drugs. These combination strategies demonstrate synergistic effects by improving tumor selectivity, increasing antitumor immunity, and overcoming treatment resistance. Nevertheless, persistent challenges, such as viral dissemination dynamics, therapy resistance, and regulatory complexities, impede the broad clinical implementation of oncolytic virus therapy (OVT). In this Review, we illustrate recent advancements and innovative therapeutic strategies in OVT within the context of contemporary cancer treatment paradigms. First, we outline the historical evolution and key milestones in OVT development. We then discuss the classification of OVs and their multimodal mechanisms that target tumorigenesis, metastasis, disease recurrence, and therapy resistance. Finally, we evaluate the clinical research progress of OVT applications, focusing on their integration with other therapies, analyze the translational barriers hindering clinical implementation, and propose evidence-based future directions for optimizing cancer treatment.