Further investigation into the tumor-killing effect of Sgc8c-M in this CDX model revealed decreased Ki67 levels and increased pHH3 staining in tumor sections, suggesting that Sgc8c-M exerts antitumor activity by inducing cell death through mitotic inhibition similar to the mitotic inhibition seen in free MMAE (Fig. 3d). Here, MKI67 is linked to neoplasm.