Chemokine receptor 7 via proline-rich tyrosine kinase-2 upregulates the chemotaxis and migration ability of squamous cell carcinoma of the head and neck.

Aberrant regulation in the chemotaxis and migration ability of cancer cells is closely associated with their metastatic activity. The chemokine receptor 7 (CCR7) has recently been shown to play an important role in regional lymph node metastasis of squamous cell carcinoma of the head and neck (SCCHN). In this study, we examined the role of proline-rich tyrosine kinase-2 (Pyk2) in CCR7-induced chemotaxis and migration ability of metastatic SCCHN cells. We showed that Pyk2 is overexpressed in squamous cell carcinoma of the head and neck. We also found that CCR7 induced Pyk2 and cofilin activation. Inhibition of Pyk2 activity using a pharmacological inhibitor, Tyrphostin A9, significantly attenuated CCR7-induced Pyk2 tyrosine phosphorylation, activation of cofilin and sequentially abolished F-actin rearrangment, diminished the chemotaxis and migration ability of SCCHN cells. In summary, our data suggest that CCR7 via Pyk2 and cofilin regulates the chemotaxis and migration ability of metastatic SCCHN cells.