VWF and melanoma: We also found strong CTHRC1 staining in fibroblasts surrounding the melanoma cell nests, and in the intimal layer of forming and newly-formed tumor blood vessels, as well as in the walls of small, normal blood vessels (Figure 3A–3I and Supplementary Figure S3), visualized using staining with the endothelial cell marker von Willebrand factor (vWF; Figure 3J, 3K).