FGF19 and neoplasm: In control PDAC xenografts, extensive fibrosis comprised over 30%–60% of tumor volumes (fibrosis scores 2–3) and included both stromal cells with a characteristic fibroblast appearance (Figure 9, A and B, and Supplemental Figure 5, A and B) and tumor cells with extensive intranuclear HMGA1 staining and cytoplasmic FGF19 staining by immunohistochemistry (IHC) (Figure 9A and Supplemental Figure 5A).