Survivin inhibition decreases cSCC cell proliferation, clonogenic ability and stemness features. (A) cSCC cell ability to proliferate in vitro after transfection with scramble or survivin siRNA was evaluated by MTT (3-4,5-dimethylyhyazol-2-y1)-2,5-diphenyltetrazolium bromide) assay; (B) Clonal growth assessment of cSCC cells after transfection with scramble or survivin siRNA by CFE. CFE was performed in triplicate in three independent experiments and quantified; ** p < 0.01; (C) Percentage of colonies with respect to size obtained from CFE assay; (D) Expression of stem cell and differentiation markers in scramble or survivin siRNA transfected cSCC cells. Cells were analysed 24 h after transfection, and levels of markers were determined by Western blot analysis. β-actin was used as loading control; (E) Representative pictures of RAD, NRAD and cSCC bulk cells after transfection with scramble or survivin siRNA, 24 h post-treatment. Scale bar = 200 µm; (F) Relative cell density evaluated by ImageJ software analysis (* 0.01 < p < 0.05; ** p < 0.01).