Penile cancer-derived cells 4, 5, and 6 presented overexpression of markers related to a CAF signature (MMP2, REAB3B, COL6A1, COL6A2, CTSK, THY1, PDGFRA, DCN, and fibroblast activation ACTA2) [31,32] (Figure 3B). Here, COL6A1 is linked to cancer.