Interleukin-17 induces CC chemokine receptor 6 expression and cell migration in colorectal cancer cells.

The CC chemokine receptor 6 (CCR6) and its ligand CCL20 are involved in human colorectal cancer (CRC) carcinogenesis and can promote the progression of CRC. In addition, interleukin-17 (IL-17), produced by a T cell subset named "Th17," has been identified as an important player in inflammatory responses, and has emerged as a mediator in inflammation-associated cancer. However, the relevance of IL-17 in the development and progression of CRC still remains to be explored. This study aimed to investigate the effect of IL-17 on the cell migration of CRC cells. Human CRC HCT-116 cells were used to study the effect of IL-17 on CCR6 expression and cell migration in CRC cells. IL-17 treatment induced migration of HCT-116 cells across the Boyden chamber membrane and increased the expression level of the CCR6. Inhibition of CCR6 by small interfering RNA (siRNA) and neutralizing antibody inhibited IL-17-induced cell migration. By using specific inhibitors and short hairpin RNA (shRNA), we demonstrated that the activation of ERK and p38 pathways are critical for IL-17-induced CCR6 expression and cell migration. Promoter activity and transcription factor ELISA assays showed that IL-17 increased NF-κB-DNA binding activity in HCT-116 cells. Inhibition of NF-κB activation by specific inhibitors and siRNA blocked the IL-17-induced CCR6 expression. Our findings support the hypothesis that CCR6 up-regulation stimulated by IL-17 may play an active role in CRC cell migration.