MMP9 and glioblastoma: Col‐16 has shown to promote formation of focal adhesion contacts and cell spreading in colon tissue.11 In addition, col‐16 has previously shown to induce cell invasion in OSCC and glioblastomas.16, 18, 19 Col‐16 induces matrix metalloproteinase 9 (MMP9) expression, which modulates the tumor microenvironment and has been associated with the acquisition of an invasive phenotype in many tumors.16 Therefore, we would also expect higher PRO‐C16 levels in stage IV.