TCF/LEF reporter assay

A549 cells were seeded in a 96-well plate for 24 h. Cells were treated with or without TGF-β1 (5 ng/mL) and sunitinib or cRGDfK. The relative TCF/LEF reporter activity was measured by the Cignal^TM TCF/LEF Reporter Assay Kit (Qiagen, Germany) according to the manufacturer’s instructions. After 48 h, cells were washed with PBS, and then lysed using passive lysis buffer (Promega, USA). Luciferase activity was evaluated using the Dual Luciferase Reporter Assay kit (Promega, USA) and normalized by the total lysate of negative control-transfected cells. All experiments were performed in triplicate.