MKI67 and neoplasm: Intravenous injection of lEVs derived from control moHSCs but not those derived from HK1 knockdown moHSCs notably promoted the growth of Hepa1-6 cell–derived orthotopic xenograft tumors (Fig. 4a), associated with elevated protein levels of HK1 and Ki67, a marker of cell proliferation, in tumor tissues (Fig. 4b).