Interleukin-6 Promotes Epithelial-Mesenchymal Transition and Cell Invasion through Integrin β6 Upregulation in Colorectal Cancer

Figure 6

Fibroblast-derived IL-6 promotes the invasion and integrin β6 upregulation in CRC cells. (a, b) ELISA assay shows IL-6 secretion from the coculture system. HT-29 (a) and Colo205 (b) cells increased the production of IL-6 from CCD-18Co cells. independent experiments. versus monoculture control. (c, d) qPCR analysis of integrin β6 gene in HT-29 (c) and Colo205 (d) cells as well as CCD-18Co cells under coculture compared to monoculture. Data represent the . independent experiments. versus CCD-18Co in monoculture control. (e, f) Immunoblots showing the role of IL-6 from the coculture system in the upregulation of integrin β6 in CRC cells. The protein level of integrin β6 in HT-29 (e) and Colo205 (f) cells was increased after coculture with CCD-18Co cells and antagonized by neutralizing antibody against IL-6. Data shown is representative of 3 independent experiments. (g, h) Transwell invasion assay showing the role of IL-6 and integrin β6 in the enhanced invasion by coculture of CRC cells with CCD-18Co cells. Both function blocking antibodies against IL-6 and integrin β6 partially suppressed the coculture system-mediated invasion of HT-29 (g) and Colo205 (h) cells, and combined inhibition demonstrated the most significant abrogation. independent experiments. versus monoculture control. ^# versus no antibody treatment coculture group.

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