Sunagawa, M. | bioRxiv Science

bioRxiv2025

Netrin-1 promotes pancreatic tumorigenesis and innervation through NEO1.

Nerves have been shown to regulate cancer progression. However, a clear demonstration of a role for axon guidance molecules in pancreatic tumorigenesis, innervation, and metastasis has been lacking. Using murine KrasG12D-mutant pancreatic organoids, we screened axon guidance molecules by qRT-PCR, identified Ntn1 upregulation, and then verified its in vivo upregulation during pancreatic tumorigenesis in humans and mice. NTN1 and its receptor NEO1 were upregulated in epithelial cells by the Kras mutation and {beta}-adrenergic signaling, in part, through the MAPK pathway. Ex-vivo culture of celiac ganglia showed that NTN1 promoted the axonogenesis of sympathetic neurons through the nerve NEO1 receptor. In the Pdx1-Cre;LSL-KrasG12D/+ model, Ntn1 knockout decreased sympathetic innervation and the development of pancreatic intraepithelial neoplasia. Treatment of pancreatic tumor organoids with recombinant NTN1 enhanced cell growth, epithelial-mesenchymal transition (EMT), and cancer stemness with the upregulation of ZEB1 and SOX9 through NEO1-mediated activation of focal adhesion kinase (FAK). In Pdx1-Cre;LSL-KrasG12D/+;LSL-Trp53R172H/+mice, Ntn1 knockout reduced innervation, FAK phosphorylation, and the features of EMT and stemness to extend mouse survival. In a liver metastasis model of PDAC (pancreatic ductal adenocarcinoma), treatment with a NTN1-neutralizing antibody or tumoral knockdown of Neo1 reduced ZEB1 and SOX9 and decreased tumor progression. In contrast, Ntn1 overexpression promoted innervation and the progression of PDAC liver metastasis. These data suggest that the NTN1/NEO1 axis is a key regulator of PDAC progression, directly influencing cancer cell stemness and EMT, while indirectly promoting tumor growth through nerves. Inhibiting the NTN1/NEO1 axis could represent a potential therapeutic approach for PDAC. Statement of SignificanceNTN1 promotes pancreatic tumorigenesis and metastasis directly and indirectly through nerves, highlighting the importance of tumor cell-nerve crosstalk in cancer. NTN1 blockade could represent a promising strategy for treating PDAC liver metastasis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=88 SRC="FIGDIR/small/666009v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@ca611corg.highwire.dtl.DTLVardef@ad9264org.highwire.dtl.DTLVardef@1661c00org.highwire.dtl.DTLVardef@b86798_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2024

Mechanoreceptor Piezo1-Mediated Interleukin Expression in Conjunctival Epithelial Cells: Linking Mechanical Stress to Ocular Inflammation

PurposeMechanical stress on the ocular surface, such as from eye-rubbing, has been reported to lead to inflammation and various ocular conditions. We hypothesized that the mechanosensitive Piezo1 channel in the conjunctival epithelium contributes to the inflammatory response at the ocular surface after receiving mechanical stimuli. MethodsHuman conjunctival epithelial cells (HConjECs) were treated with Yoda1, a Piezo1-specific agonist, and various allergens to measure cytokine expression levels using qRT-PCR and Western blot. Piezo1 activation-induced intracellular signaling pathways were also investigated. Mechanical stretching experiments were conducted to simulate Piezo1 activation in HConjECs. In in vivo studies, using immunohistochemistry, rats were administered Yoda1 eye drops to examine the inflammatory response in the conjunctiva and Piezo1-induced signaling activation. ResultsHConjECs expressed functional Piezo1 channel, and its activation significantly increased IL-6 and IL-8 expression through the p38 MAPK-CREB pathway. Piezo1-induced [Ca2+]i elevation was crucial for the production of IL-6. Mechanical stretching mimicked these effects. In vivo, Yoda1 administration led to enhanced immunoreactivity of phospho-p38 MAPK and phospho-CREB and increased IL-6 in the rat conjunctival epithelium. Significant neutrophil infiltration was also observed after Piezo1 channel activation without affecting eosinophil numbers. ConclusionMechanical stress-induced Piezo1 channel activation in conjunctival epithelial cells can cause ocular inflammation by upregulating pro-inflammatory cytokines via the p38 MAPK-CREB pathway and promoting neutrophil infiltration. These findings suggest that mechanical stimuli on ocular surface tissues are significant risk factors for ocular inflammation. HighlightsO_LIPiezo1 channel activation increased IL-6 via p38 MAPK-CREB pathway in Human conjunctival epithelial cells (HConjECs). C_LIO_LIPiezo1 activation mimicked fungal extract but not pollen or dust mite. C_LIO_LIMechanical stretching mimicked Piezo1 effects, boosting IL-6 production in HConjECs. C_LIO_LIPiezo1 activation elevated p-p38 MAPK, p-CREB, and IL-6 in the rat conjunctiva. C_LIO_LIPiezo1 activation leads to neutrophil infiltration in the rat conjunctival epithelium. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=152 SRC="FIGDIR/small/600298v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@1c68f87org.highwire.dtl.DTLVardef@f9226corg.highwire.dtl.DTLVardef@42f264org.highwire.dtl.DTLVardef@1378c99_HPS_FORMAT_FIGEXP M_FIG C_FIG Mechanosensitive Piezo1 channel activation induces IL-6 expression in the conjunctival epithelial cells via elevation of [Ca2+]i and activation of p38 MAPK and transcription factor CREB. Mechanical stress stimulates Piezo1 channel and Ca2+ influx through it, which induces activation of p38 MAPK. A transcription factor CREB is phosphorylated after p38 MAPK activation, then promotes IL-6 transcription.

physiology↗