To further investigate whether the enzymatic activity of TET1 protein is disposable for its tumor-suppressive effects on UBC cells, we stably ectopically expressed TET1 catalytic domain (TET1-CD) and its enzymatically inactive mutant (TET-CDmut) in T24 cells, which express low level of endogenous TET1 protein (Figure 3A). The gene discussed is TET1; the disease is neoplasm.