To examine whether YY2 exerts its tumor suppressive effect by regulating SAC activity, we treated YY2‐overexpressed HCT116 cells with reversine, a SAC activity inhibitor.[33, 34] In control cells, reversine treatment reduced cyclin B and securin accumulation to levels significantly lower than those in control cells; meanwhile, in YY2‐overexpressed cells, it reduced cyclin B and securin accumulation induced by YY2 overexpression to levels near to those in control cells (Figure S3J, Supporting Information). Here, YY2 is linked to neoplasm.