Neural control of Immunotherapy: how Tumor-innervation shapes Anti-Tumor immune responses.

The role of the sympathetic nervous system (SNS) in cancer biology has gained increasing attention, and its ability to affect immunotherapy is starting to become clearer. Extensive evidence shows that neuro-onco-immune interactions significantly influence tumor progression and the effectiveness of cancer treatments. Blocking SNS signaling, primarily through β-adrenergic receptors, enhances immune cell functions, by increasing CD8 T-cell activation and cytokine production, while reducing immunosuppressive cell populations. This review explores the relationship between SNS signaling and cancer immunotherapy, emphasizing how SNS activation affects the efficacy of various immunotherapies, including immune modulators, immune checkpoint inhibitors, oncolytic virus therapy, therapeutic vaccines, and CAR-T cell therapies. We summarize retrospective studies investigating the use of β-blockers during immunotherapy, suggesting potential benefits for treatment outcomes of blocking SNS signaling in the tumor microenvironment. We examine ongoing clinical trials that evaluate the use of beta-blockers with immune checkpoint inhibitors, which aim to improve patient outcomes. While translational and preclinical studies provide ample evidence for targeting SNS signaling in cancer immunotherapy, clinical studies are only beginning to emerge. Ultimately, this review underscores the need for further research to better understand how SNS signaling can be targeted to optimize immunotherapy, paving the way for more effective treatment strategies.