The final cluster identified contained extracellular matrix proteins, such as collagens (COL6A1, COL1A2, COL3A1, COL12A1, COL15A1, COL14A1), fibrillin-1 (FBN1), desmin (DES) and vimentin (VIM) (Figure 4A).We selected 65 upregulated proteins in tumor tissues to further analyze protein-protein interaction as downregulated proteins may not be suitable for potential biomarkers [26]. Here, COL15A1 is linked to neoplasm.