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

Figure 5

STAT-3 pathway is involved in IL-6-mediated cell invasion and upregulation of integrin β6. (a, b) Immunoblots showing the effect of IL-6 (20 ng/ml) with indicated treatment intervals on the expression of phospho-STAT-3 (Tyr705) (p-STAT-3) and total-STAT-3 (t-STAT-3) in HT-29 (a) and Colo205 (b) cells. (c, e) Transwell invasion assay showing the role of the STAT-3 pathway in IL-6-induced invasion. HT-29 and Colo205 cells were pretreated with STAT-3 specific inhibitor Stattic or CTS (5 μM) (c) for 1 h or with siRNA (e) for 24 h to knock down STAT-3, followed by stimulation with IL-6 (20 ng/ml) for 24 h. Data represent the . independent experiments. versus no IL-6 treatment control. ^# versus IL-6-treated group. (d, f) Immunoblots showing the role of the STAT-3 pathway in IL-6-mediated upregulation of integrin β6. HT-29 and Colo205 cells were pretreated with STAT-3 specific inhibitor Stattic (5 μM) (d) or siRNA (f) before the treatment with IL-6 (20 ng/ml) for 24 h, and the expression of integrin β6 was detected. (a, b, d, f) Data shown is representative of 3 independent experiments.

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