PROS1 and meningioma: Genes found to be downregulated in grade III meningioma with reported tumour suppressor roles in various other cancers included FBLN1. As an extracellular matrix (ECM) protein of the fibulin family, FBLN1 functions in the organisation of ECM supramolecular structures, thereby playing a role in the regulation of cell morphology, growth, adhesion and motility [44].