MMP14 and neoplasm: While prior in vitro immunocytochemistry analyses indicated higher expression of MMP-14 in U87 cells relative to D54 cells 29, orthotopic U87 and D54 xenograft tumors in the present studies did not show a significant difference in the tumor-to-normal brain ratio (TBR) for MMP-14 immunofluorescence (p>0.05, Figure S7C).