Physiological link between PAX3/FKHR and TFAP2B. (a) Cell proliferation of mock-transfected Rh4 cells and cells stably overexpressing mTFAP2B as measured by MTT assay at indicated time points after PAX3/FKHR silencing. Treatment with siRNA specific for PAX3/FKHR was compared to scRNA, siRNA targeting GAPDH and GeneEraser alone. (b) Comparison of apoptosis rates in parental Rh4 cells, Rh4 cells stably overexpressing TFAP2B and mock-transfected Rh4 cells as measured by FACS of PI-stained cells 24 h after downregulation of PAX3/FKHR. GAPDH, glyceraldehyde-3-phosphate dehydrogenase; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; PI, propidium iodide; scRNA, scrambled siRNA; siRNA, small interfering RNA.