KLK4 and head and neck squamous cell carcinoma: In this study, we applied global gene expression profiling on samples of a well-established mouse model of tumor recurrence, and identified differentially expressed candidate genes some of which have been described previously in the context of HNSCC development or tumor recurrence, such as mucins, kallikreins, tryptase alpha/beta 1, claudin-10 and lactotransferrin [15-20].