CLIC3 and meningioma: In meningiomas with AKT1E17K/TRAF7 mutations, we identified upregulation of CLIC3, an intracellular chloride channel involved in metalloprotease secretion, tumour migration, and invasion, as reported in ovarian, breast, and pancreatic cancers.55, 56, 57 Another overexpressed protein, CRABP2, from the retinoic acid family, is highly expressed in arachnoid and dura fibroblasts.58