It was previously observed that PDT with PS Hypocrellin-A and -B induces VEGF and endostatin release in glioma cells while reducing endostatin release in endothelial cells, and it has been shown that the predominance of the VEGF over endostatin observed early after PDT may contribute to enhanced angiogenesis [26,35]. This evidence concerns the gene COL18A1 and glioma.