Nerve Growth Factor Promotes Gastric Tumorigenesis through Aberrant Cholinergic Signaling

Within the gastrointestinal stem cell niche, nerves help to regulate both normal and neoplastic stem cell dynamics. Here, we reveal the mechanisms underlying the cancer-nerve partnership. We find that Dclk1+ tuft cells and nerves are the main sources of acetylcholine (ACh) within the gastric mucosa. Cholinergic stimulation of the gastric epithelium induced nerve growth factor (NGF) expression, and in turn NGF overexpression within gastric epithelium expanded enteric nerves and promoted carcinogenesis. Ablation of Dclk1+ cells or blockade of NGF/Trk signaling inhibited epithelial proliferation and tumorigenesis in an ACh muscarinic receptor-3 (M3R)-dependent manner, in part through suppression of yes-associated protein (YAP) function. This feedforward ACh-NGF axis activates the gastric cancer niche and offers a compelling target for tumor treatment and prevention. [Display omitted] •NGF expression is induced in gastric cancer by ACh from nerves and tuft cells•NGF promotes innervation and proliferation in gastric epithelium•Blockade of NGF or ablation of cholinergic tuft cells inhibits tumor development•Cholinergic signaling activates YAP signaling that is essential for Wnt activation Hayakawa et al. use a series of mouse models to show that acetylcholine from Dclk1+ tuft cells and nerves induces NGF in gastric epithelial cells, which promotes neuron expansion and tumorigenesis. YAP is activated through the cholinergic signaling, and inhibition of this pathway can block NGF-driven tumors.