MKI67 and neoplasm: Notably, tumor xenograft with FLAG-FBXO7 overexpression showed the decreased intensity of Ki-67 staining, accompanied by increased intensity of 8-oxo-dG (a marker of oxidative stress) and cleaved caspase 3 (an apoptosis marker) staining, all of which were obviously rescued by expressing PRMT1 K37R mutant, but not PRMT1 WT (Fig. 6i, Supplementary Fig. 6g).