MKI67 and neoplasm: Immunostaining of KELLY tumor samples excised at seven days confirmed loss of RUNX1T1 following its knockdown, as well as decreased cell proliferation as indicated by a reduced Ki67 proliferative index (47.5 ± 4.4% in knockdown tumors compared to 80.4 ± 4.3% in control tumors; P = 0.029) (Fig. 5g, left panels).