Piezo1 promotes EMT and tumor progression in HNSCC through a YAP1-Associated Galectin-1 axis.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is an aggressive malignancy in which epithelial-mesenchymal transition (EMT) contributes to tumor progression. Piezo1 and Galectin-1 have each been implicated in cancer progression, but their functional relationship in HNSCC remains incompletely understood. We investigated Piezo1-associated mechanosensitive signaling and its potential relationship with Galectin-1 in HNSCC. METHODS: Public transcriptomic and proteomic analyses were integrated with validation using 16 paired oral squamous cell carcinoma (OSCC) tumor and adjacent non-tumor specimens. Functional studies were performed in HNSCC cell lines using genetic and pharmacological modulation of PIEZO1/Piezo1 and Galectin-1-associated signaling. Two independent SCC-9 xenograft studies were conducted in separate cohorts (n = 6 per group): one comparing vehicle, Yoda1, and GsMTx4, and the other comparing vehicle, GsMTx4, OTX008, and their combination. RESULTS: Piezo1 was consistently upregulated in HNSCC datasets, OSCC tissues, and HNSCC cell lines, whereas its association with survival was modest and not uniformly reproduced across analytical platforms. Piezo1 activation was associated with increased Ca2+-associated signaling, nuclear YAP1 accumulation, and EMT-related phenotypes, whereas PIEZO1 silencing and pharmacological inhibition of mechanosensitive channel activity attenuated these effects. Galectin-1 emerged as a Piezo1-responsive candidate effector associated with YAP1 signaling and EMT-related phenotypes. OTX008 treatment reduced proliferation, wound closure, invasion, and EMT-related marker changes. In xenografts, combined GsMTx4 and OTX008 treatment produced greater reductions in tumor growth, Ki67 positivity, endpoint CD31 fluorescence intensity, and EMT-associated marker changes than either monotherapy at the tested doses. CONCLUSION: These findings support an important contribution of Piezo1-associated mechanosensitive signaling to EMT-related phenotypes and tumor progression in HNSCC and support Galectin-1 as a functionally relevant, Piezo1-responsive candidate effector associated with YAP1 signaling. The greater antitumor effects observed with combined GsMTx4 and OTX008 treatment support further investigation of co-targeting mechanosensitive channel activity and Galectin-1 in HNSCC.