To determine whether STAT3 is activated in colorectal cancer stem cells, we separated ALDH+/CD133+ and ALDH−/CD133− subpopulations from DLD-1, HCT-116, SW480, and HT29 colorectal cancer cell lines by flow cytometry, as previously described (Ginestier et al, 2007). This evidence concerns the gene LDHA and colorectal cancer.