Targeting sensory nerves in the tumor microenvironment: a new vulnerability in cancer therapy.

Tumor innervation, the infiltration of nerves into the tumor microenvironment (TME), is increasingly recognized as a novel hallmark driving cancer progression and is associated with poor patient prognosis across various solid malignancies. This process is orchestrated by a complex, bidirectional crosstalk. Cancer and stromal cells release neurotrophic factors that induce axonogenesis or neurogenesis. In turn, the infiltrating nerves, particularly sensory nerves, secrete neurotransmitters, neuropeptides or form pseudo-synapse with tumor cells to facilitate cancer hallmarks, including sustained proliferation, invasion, metastasis, modulation of the anti-tumor immune response, and cancer plasticity. However, the specific contributions and underlying mechanisms of sensory nerve innervation in orchestrating malignancy remain incompletely elucidated. This review aims to synthesize the current understanding of the multifaceted roles of sensory neurons within the TME, detailing their intricate interactions with cancer and stromal cells, and highlighting the emerging therapeutic strategies that target the sensory nerve-tumor axis.