ADAM23 and astrocytoma (excluding glioblastoma): Although preliminary, three essential aspects of ADAM23 expression in brain tissues can provide insights into the functional relevance of ADAM23 in clinical samples: (1) ADAM23 is downregulated in diffusely infiltrating astrocytomas relative to normal brain, (2) ADAM23 is downregulated at the invasive front of GBM relative to the tumor core, and (3) ADAM23 downregulation is correlated with higher FLAIR volumes, a manifestation of a combination of increased tumor infiltration and edema.