ROR2 and Hand-foot syndrome: By purifying integrin α6high/CD34+ HFSCs from mouse HFs at telogen (referred as quiescent HFSC; qHFSC) and anagen onset (referred as activated HFSC; aHFSCs) using fluorescence-activated cell sorting (FACS), we confirmed that ROR2 protein level was elevated in aHFSCs as compared to qHFSCs (Fig. 1b and Supplementary Fig. 1c).