In addition, gene set enrichment analysis (GSEA) employing an iCAF signature gene set obtained from a recent study demonstrated a strong enrichment of iCAF‐related genes in FGF19‐treated LX‐2 cells (Figure S3A, Supporting Information).[11] To further confirm the association of FGF19 with iCAFs, we treated LX‐2 cells with FGF19‐containing cancer cell conditioned medium (CM) or rhFGF19 and detected the expression of iCAF (IL1A, IL1B, IL6, CXCL1, and CXCL5) and myCAF (α‐SMA, ACTG2, COL1A1, COL2A1) markers. The gene discussed is IL1A; the disease is cancer.