Immunohistochemical staining for Ki-67, an indicator of tumor progression, revealed markedly fewer intratumoral Ki-67-positive cells in cetuximab variant groups, indicating that the cetuximab variants effectively inhibited EGFRWTand EGFRMut tumor cell proliferation in the xenograft model (Supplementary Fig. 8a–d). Here, MKI67 is linked to neoplasm.