FN1 and cancer: We next used IHC to assess the content of four ECM molecules (collagen 1 (COL1A1), fibronectin (FN1), versican (VCAN), cathepsin-B (CTSB), and one glycosaminoglycan chondroitin sulfate (CS), which were selected based on their high level of expression in cancer tissues1 and/or their association with the macrophage phenotype as described above (Fig. 1).