Forkhead Box q1 promotes invasion and metastasis in colorectal cancer by activating the epidermal growth factor receptor pathway

Figure 4 Forkhead Box q1 regulates epidermal growth factor receptor and downstream signaling pathways by regulating heparin binding epidermal growth factor. A: Quantitative real-time polymerase chain reaction (qRT–PCR) was performed to analyze the levels of forkhead Box q1 (FOXQ1), heparin binding epidermal growth factor (HB-EGF), epidermal growth factor receptor (EGFR), Akt, kRas and Raf in DLD1-shFOXQ1 and DLD1-shControl cells; B: qRT–PCR was performed to analyze the levels of FOXQ1, HB-EGF, EGFR, AKT, RAF and KRAS in SW480-shFOXQ1 and SW480-shControl cells; C: Western blot analyses were performed to analyze the protein levels of FOXQ1, HB-EGF, EGFR, RAF and KRAS as well as the phosphorylation levels of PI3K, Akt, and MAPK in DLD1-shFOXQ1, SW480-shFOXQ1, DLD1-shControl and SW480-shControl cells. β-actin was used as the loading control; D: Exogenous rhHB-EGF (50 ng/mL) was added to the culture media of DLD1-shFOXQ1 and SW480-shFOXQ1 cells for 1.5 h and 2 h, respectively. Western blotting was performed to detect the expression of proteins in the HB-EGF/EGFR signaling pathway. ^aP < 0.05; ^bP < 0.01; ^cP < 0.001 indicate significant differences compared to the control group (two-tailed, unpaired Student’s t test). Bars represent the mean ± S.E. of three independent experiments. rhHB-EGF: Recombinant human HB-EGF; FOXQ1: Forkhead Box q1; HB-EGF: Heparin binding epidermal growth factor.