Tumor state 3 (TS3) is defined by cluster markers CHI3L1, TAGLN, ITGAV and VCAM1, along with a decrease in expression level of GLI1 (Fig. 1d), a canonical driver of hedgehog signaling in BCC tumors, typically associated with a switch away from dependency on this signaling pathway. The gene discussed is CHI3L1; the disease is skin basal cell carcinoma.