PI16 and esophageal squamous cell carcinoma: Consistent with the finding that PI16 is mainly expressed in fibroblasts (the data were extracted from GEO (GSE134355) or Bioproject (PRJNA554845), and the map was drawn with UCSC Cell Browser (Supplementary Fig. 6), we conducted qPCR on fibroblasts and ESCC cells and found that PI16 was highly expressed in LN-Fbs and remained at a low level in ESCC cells.