ALDH1A1 and neoplasm: To confirm the immune-cytochemical observations that TNF-β-induced CSCs formation in an alginate tumor microenvironment and that resveratrol can modulate this effect and additionally to demonstrate the chemosensitization effect of resveratrol to 5-FU on CSC markers (CD133, CD44 and ALDH1) expression, western blotting analysis was performed (Figure 2C,D).