MKI67 and neoplasm: IHC analysis showed that the tumours formed from the circMYH9 shRNA-transfected HCT116 cells exhibited weaker Ki67 staining (Fig. 2O, Figure S1R) and that formed from circMYH9 overexpressing LoVo cells exhibited stronger Ki67 staining than the tumours derived from the vector-transfected cells (Fig. 2P, Figure S1S).