Bioactive Vitamin D Attenuates MED28-Mediated Cell Growth and Epithelial–Mesenchymal Transition in Human Colorectal Cancer Cells

Figure 3

Calcitriol suppressed the upregulatory effect of MED28 on cell growth and epithelial-mesenchymal transition in SW480 human colorectal cancer cells. SW480 cells were treated with calcitriol (100 nM) for 48 h (a), undergone MED28-specific siRNA (siMED28) for 72 h (b), or MED28 overexpression plasmid (Flag-MED28) for 48 h (c), with respective controls, and subjected to Western blotting. The ratios below the representative images (left panels) indicate the relative expression of the specific proteins with respect to those of 0 nM (a), siControl (b), or pcDNA3 (c) after normalization with the expression of the corresponding loading controls, β-actin, α-tubulin, GAPDH, or vinculin. Densitometric data (right panels) are expressed as , ; , , and as compared with 0 nM (a), siControl (b), or pcDNA3 (c). (d) SW480 cells were transfected with MED28 overexpression plasmid (Flag-MED28), followed by the addition of calcitriol for 48 h, and then subjected to Western blotting. “–” indicates vehicle control (0 nM of calcitriol) or pcDNA3 transfection. The ratios below the representative images (left panel) indicate the relative expression of the specific proteins with respect to those of lane 1 (0 nM and pcDNA3) after normalization with the expression of the corresponding loading controls, β-actin, or GAPDH. Densitometric data (right panel) are expressed as , ; and as compared with lane 1 (0 nM and pcDNA3); as compared with lane 2 (0 nM and Flag-MED28).

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