FOXM1 and malignant colon neoplasm: Expression of E2F1 was not affected by FOXM1 overexpressing HCT116 cells, (Fig. 2C,D) but in thiostrepton treated HCT116 and HT29 colon cancer cells,(Fig. 3B,C) E2F1 was downregulated, suggesting that E2F1 is regulated by FOXM1.