MMP2 and glioblastoma: PDGF induced by TNIIIA2 was also shown to upregulate the expression of tenascin-C, a parental protein of TNIIIA2, which in turn induced an increase in MMP-2 activity in GBM cells and rat brain-derived fibroblasts, leading to a further liberation of the TNIIIA2 function from tenascin-C molecule.