The angiogenesis marker ED-B plus fibronectin isoform in intracranial meningiomas

Fibronectins (FNs), adhesive glycoproteins mainly expressed in the extracel lular matrix, are polymorphic molecules whose various isoforms are dependen t on alternative splicing patterns. The isoform containing the ED-B sequenc e and occurring in foetal and neoplastic tissues (oncofoetal or B+FN) has b een previously recognized as a marker for angiogenesis. The distribution of this isoform was analyzed in a consecutive series of 13 4 surgically obtained intracranial meningiomas, using specific monoclonal a ntibodies. Oncofoetal FN was found to be widely distributed in the vessels of anaplastic meningiomas, with its expression being restricted in the vasc ulature of the typical subtypes, and absent in the neighbouring cerebral ti ssue. The ubiquitous vascular expression of B+FN in meningiomatous malignan cies might provide a potential target for the in vivo delivery of angiosupp ressive agents.