PTK2 and nasopharyngeal carcinoma: To examine the role of FAK in CLCA2-inhibited nasopharyngeal carcinoma cellular motility, we used siRNA to knockdown CLCA2 expression in nasopharyngeal carcinoma cells and found that expression of phospho-FAK and downstream phospho-ERK1/2 were enhanced by silencing CLCA2 in S26 and SUNE-1 cells compared with negative controls (Fig. 5a).