Objective: To explore whether Src activity is regulated by the binding of chemokine receptor 7 (CCR7) and CCL19 in salivary gland tumor. We also aim to elucidate whether Src is capable of regulating invasion and migration of head and neck squamous cell carcinoma (HNSCC) cells.
Materials and methods: PCI-37B cells were first treated with 20 μM PP2 for 30 min or 10 μg/mL CCR7mAb for 4 h, respectively, followed by 200 ng/mL CCL19 induction for 5 min. Western blot was conducted to detect protein levels of p-Src, p-Pyk2 and p-Paxillin. Transwell assay was performed to access migratory and invasive abilities of PCI-37B cells. Immunofluorescence was finally conducted to observe changes in cell cytoskeleton.
Results: CCL19 induction in PCI-37B cells upregulated protein levels of p-Src, p-Pyk2 and p-Paxillin, which were downregulated by PP2 treatment. Src activation induced by CCL19 enhanced invasive and migratory abilities of PCI-37B cells. However, PP2 treatment reversed invasive and migratory abilities even after CCL19 induction. CCL19-induced PCI-37B cells were shaped as irregular polygon and closely connected. Large flak pseudopods were observed and invasive pseudopodia connections markedly increased after CCL19 induction. F-actin body was found in pseudopodia. PP2 treatment resulted in fewer pseudopodia and regularly arranged actin filaments.
Conclusions: Src activation is regulated by binding of CCR7 and CCL19 in salivary gland tumor. Activated Src alters cell adhesion ability and cytoskeleton by regulating Pyk2 and Paxillin, thus elevating invasive and migratory abilities of HNSCC cells.