We then performed IHC analysis of xenograft tumor specimens (Fig. 3G), which revealed that KI67 expression was significantly lower in the PPP2R2B overexpression group (Fig. 3H), whereas levels of cleaved-caspase 3 were higher (Fig. 3I), providing further support for the hypothesis that PPP2R2B inhibits BC cell proliferation and increases their sensitivity to cisplatin. Here, MKI67 is linked to breast cancer.