YKL-40 gene expression was primarily increased in the fibroblast (gene annotation: COL1A, BGN, DCN), myeloid (gene annotation: CD68, LYZ, AIF1), cancer (gene annotation: EPCAM, KRT7, KRT18), and B-cell (gene annotation: CD79A, CD79B) populations in cancer tissue compared to healthy tissue (Figure 1D–F). Here, KRT18 is linked to cancer.