Abstract
Collective cell migration (CCM) is characterized by the coordinated movement of cell groups while maintaining cell-to-cell cohesion. Despite extensive research on CCM, the collective migration of mature epithelial cells over the extracellular matrix in response to external stimuli has not been reported. Using intravital imaging in mice, we identified urothelial CCM (UCCM) triggered by immunogenic substances, including bladder cancer cells (MB49) and uropathogenic Escherichia coli (UPEC). Integrin signaling inhibitors suppress UCCM, significantly enhancing MB49 tumor growth and UPEC bladder infection. UCCM initiation involves Toll-like receptor 4 (TLR4), we designated this TLR4-associated UCCM as the urothelial collective-gliding response (UCGR). Downstream of integrin signaling, urothelial matrix metalloproteinases (MMP)-8 and MMP-9 mediate UCGR. Intravesical instillation of these factors accelerates UCCM and inhibits tumor growth and infection. UCGR may represent a TLR4-associated defense mechanism, offering potential therapeutic strategies for bladder disorders such as refractory cystitis and recurrent non-muscle invasive bladder cancer after endoscopic resection.
