NAMPT and neoplasm: To explore the effect of visfatin-pretreated ADSCs (vADSCs) on MDA-MB-231 tumor formation in vivo, we used an orthotopic xenograft nude mouse model formed by co-injecting MDA-MB-231 and vADSCs or untreated ADSCs (uADSCs), noted as V50 or Ctrl, respectively, into the mammary fat pads subcutaneously.