KLK5 and oral cavity squamous cell carcinoma: In bladder carcinoma cells, siRNA-mediated inhibition of KLK5 expression led to a significant reduction of invasion in Matrigel-based assays [44], whereas in oral squamous cell carcinoma cells silencing of KLK5 enforced cell-cell adhesion that promoted loss of junctional integrity and, hence, metastasis [45].