Platelet-derived growth factor receptor-α and -β promote cancer stem cell phenotypes in sarcomas

a Western blot analysis of cell surface markers for cancer stem-like cells in human sarcoma cell lines HT1080, SK-LMS-1, and DDLS8817. Cells were grown as monolayers or spheroids. β-actin was used as the loading control. b Percentage of CD133(+) cells in human sarcoma cells grown as monolayers or as spheroids as determined by FACS analysis. *p？<？0.05 compared to Monolayers. c Western blot analysis of human sarcoma cells grown as monolayers or as spheroids for self-renewal transcription factors. d Western blot analysis of FACS-sorted CD133(+) and CD133(？) spheroid cells for self-renewal transcription factors. Experiments in a–d were performed three times with similar results. e Representative light microscopy images from single cell assays performed in triplicate for human sarcoma spheroid cells FACS-sorted by CD133. Graph displays the mean diameters of the spheroid colonies. Bars represent standard deviation. *p？<？0.05 compared to CD133(？