It is important to highlight that similar Sdf1 and Cxcr4 upregulation was observed in primary PD/S-SCCs (spontaneously developed in K14-HPV16 mice [11]) and in PD/S-SCCs that were engrafted in syngeneic immunocompetent mice, relative to their respective WD-SCCs (Supplementary Fig. 1C and 1D). Here, CXCR4 is linked to Wilson disease.