Western blot analysis was done as previously described (16 (link)). The antibodies for rabbit polyclonal NTSR1 (PA3-214, 1:2500 dilution) and rabbit monoclonal cyclin D1 (2261-1, 1:5000 dilution) were purchased from Thermo fisher Scientific (Rockford, IL, USA) and Epitomics (Burlingame, CA), respectively. The rabbit polyclonal IL-8 (ab106350, 1:500 dilution) and mouse monoclonal anti-β-actin (A5316, 1:5000 dilution) antibodies were obtained from Abcam (Cambridge, MA, USA) and Sigma-Aldrich, respectively.