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Background: Cerebral cavernous malformations (CCMs) are vascular malformations characterized by clusters of enlarged leaky capillaries in the central nervous system. They may result in intracranial haemorrhage, epileptic seizure(s), or focal neurological deficits, and potentially lead to severe disability. Globally, CCMs represent the second most common intracranial vascular malformation in humans, and their familial form (FCCMs) accounts for one-fifth of cases. Neurosurgical excision, and perhaps stereotactic radiosurgery, is the only available therapeutic option. Case reports suggest that propranolol might modify disease progression. Methods: Treat_CCM is a prospective, randomized, open-label, blinded endpoint (PROBE), parallel-group trial involving six Italian clinical centres with central reading of brain magnetic resonance imaging (MRI) and adverse events. Patients with symptomatic FCCMs are randomized (2:1 ratio) either to propranolol (40-80 mg twice daily) in addition to standard care or to standard care alone (i.e. anti-epileptic drugs or headache treatments). The primary outcome is intracranial haemorrhage or focal neurological deficit attributable to CCMs. The secondary outcomes are MRI changes over time (i.e. de novo CCM lesions, CCM size and signal characteristics, iron deposition, and vascular leakage as assessed by quantitative susceptibility mapping and dynamic contrast enhanced permeability), disability, health-related quality of life, depression severity, and anxiety (SF-36, BDI-II, State-Trait Anxiety Inventory). Discussion: Treat_CCM will evaluate the safety and efficacy of propranolol for CCMs following promising case reports in a randomized controlled trial. The direction of effect on the primary outcome and the consistency of effects on the secondary outcomes (even if none of them yield statistically significant differences) of this external pilot study may lead to a larger sample size in a definitive phase 2 trial. Trial registration: Clinical

During vessel sprouting, endothelial cells (ECs) dynamically rearrange positions in the sprout to compete for the tip position. We recently identified a key role for the glycolytic activator PFKFB3 in vessel sprouting by regulating cytoskeleton remodelling, migration and tip cell competitiveness. It is, however, unknown how glycolysis regulates EC rearrangement during vessel sprouting. Here we report that computational simulations, validated by experimentation, predict that glycolytic production of ATP drives EC rearrangement by promoting filopodia formation and reducing intercellular adhesion. Notably, the simulations correctly predicted that blocking PFKFB3 normalizes the disturbed EC rearrangement in high VEGF conditions, as occurs during pathological angiogenesis. This interdisciplinary study integrates EC metabolism in vessel sprouting, yielding mechanistic insight in the control of vessel sprouting by glycolysis, and suggesting anti-glycolytic therapy for vessel normalization in cancer and non-malignant diseases.

During vessel sprouting, endothelial cells (ECs) dynamically rearrange positions in the sprout to compete for the tip position. We recently identified a key role for the glycolytic activator PFKFB3 in vessel sprouting by regulating cytoskeleton remodelling, migration and tip cell competitiveness. It is, however, unknown how glycolysis regulates EC rearrangement during vessel sprouting. Here we report that computational simulations, validated by experimentation, predict that glycolytic production of ATP drives EC rearrangement by promoting filopodia formation and reducing intercellular adhesion. Notably, the simulations correctly predicted that blocking PFKFB3 normalizes the disturbed EC rearrangement in high VEGF conditions, as occurs during pathological angiogenesis. This interdisciplinary study integrates EC metabolism in vessel sprouting, yielding mechanistic insight in the control of vessel sprouting by glycolysis, and suggesting anti-glycolytic therapy for vessel normalization in cancer and non-malignant diseases.

Junctional Adhesion Molecule-A (JAM-A) is a transmembrane adhesive protein expressed at endothelial junctions and in leukocytes. Here we report that JAM-A is required for the correct infiltration of polymorphonuclear leukocytes (PMN) into an inflamed peritoneum or in the heart upon ischemia-reperfusion injury. The defect was not observed in mice with an endothelium-restricted deficiency of the protein but was still detectable in mice transplanted with bone marrow from JAM-A(-/-) donors. Microscopic examination of mesenteric and heart microvasculature of JAM-A(-/-) mice showed high numbers of PMN adherent on the endothelium or entrapped between endothelial cells and the basement membrane. In vitro, in the absence of JAM-A, PMN adhered more efficiently to endothelial cells and basement membrane proteins, and their polarized movement was strongly reduced. This paper describes a nonredundant role of JAM-A in controlling PMN diapedesis through the vessel wall

Tight junctions are the most apical components of endothelial and epithelial intercellular cleft. In the endothelium these structures play an important role in the control of paracellular permeability to circulating cells and solutes. The only known integral membrane protein localized at sites of membrane-membrane interaction of tight junctions is occludin, which is linked inside the cells to a complex network of cytoskeletal and signaling proteins. We report here the identification of a novel protein (junctional adhesion molecule [JAM]) that is selectively concentrated at intercellular junctions of endothelial and epithelial cells of different origins. Confocal and immunoelectron microscopy shows that JAM codistributes with tight junction components at the apical region of the intercellular cleft. A cDNA clone encoding JAM defines a novel immunoglobulin gene superfamily member that consists of two V-type Ig domains. An mAb directed to JAM (BV11) was found to inhibit spontaneous and chemokine-induced monocyte transmigration through an endothelial cell monolayer in vitro. Systemic treatment of mice with BV11 mAb blocked monocyte infiltration upon chemokine administration in subcutaneous air pouches. Thus, JAM is a new component of endothelial and epithelial junctions that play a role in regulating monocyte transmigration.

The molecular basis of lymphangiogenesis remains incompletely characterized. Here, we document a novel role for the PDZ domain-containing scaffold protein synectin in lymphangiogenesis using genetic studies in zebrafish and tadpoles. In zebrafish, the thoracic duct arises from parachordal lymphangioblast cells, which in turn derive from secondary lymphangiogenic sprouts from the posterior cardinal vein. Morpholino knockdown of synectin in zebrafish impaired formation of the thoracic duct, due to selective defects in lymphangiogenic but not angiogenic sprouting. Synectin genetically interacted with Vegfr3 and neuropilin-2a in regulating lymphangiogenesis. Silencing of synectin in tadpoles caused lymphatic defects due to an underdevelopment and impaired migration of Prox-1(+) lymphatic endothelial cells. Molecular analysis further revealed that synectin regulated Sox18-induced expression of Prox-1 and vascular endothelial growth factor C-induced migration of lymphatic endothelial cells in vitro. These findings reveal a novel role for synectin in lymphatic development., The molecular basis of lymphangiogenesis remains incompletely characterized. Here, we document a novel role for the PDZ domain-containing scaffold protein synectin in lymphangiogenesis using genetic studies in zebrafish and tadpoles. In zebrafish, the thoracic duct arises from parachordal lymphangioblast cells, which in turn derive from secondary lymphangiogenic sprouts from the posterior cardinal vein. Morpholino knockdown of synectin in zebrafish impaired formation of the thoracic duct, due to selective defects in lymphangiogenic but not angiogenic sprouting. Synectin genetically interacted with Vegfr3 and neuropilin-2a in regulating lymphangiogenesis. Silencing of synectin in tadpoles caused lymphatic defects due to an underdevelopment and impaired migration of Prox-1(+) lymphatic endothelial cells. Molecular analysis further revealed that synectin regulated Sox18-induced expression of Prox-1 and vascular endothelial growth factor C-induced migration of lymphatic endothelial cells in vitro. These findings reveal a novel role for synectin in lymphatic development.

The molecular basis of lymphangiogenesis remains incompletely characterized. Here, we document a novel role for the PDZ domain-containing scaffold protein synectin in lymphangiogenesis using genetic studies in zebrafish and tadpoles. In zebrafish, the thoracic duct arises from parachordal lymphangioblast cells, which in turn derive from secondary lymphangiogenic sprouts from the posterior cardinal vein. Morpholino knockdown of synectin in zebrafish impaired formation of the thoracic duct, due to selective defects in lymphangiogenic but not angiogenic sprouting. Synectin genetically interacted with Vegfr3 and neuropilin-2a in regulating lymphangiogenesis. Silencing of synectin in tadpoles caused lymphatic defects due to an underdevelopment and impaired migration of Prox-1(+) lymphatic endothelial cells. Molecular analysis further revealed that synectin regulated Sox18-induced expression of Prox-1 and vascular endothelial growth factor C-induced migration of lymphatic endothelial cells in vitro. These findings reveal a novel role for synectin in lymphatic development., The molecular basis of lymphangiogenesis remains incompletely characterized. Here, we document a novel role for the PDZ domain-containing scaffold protein synectin in lymphangiogenesis using genetic studies in zebrafish and tadpoles. In zebrafish, the thoracic duct arises from parachordal lymphangioblast cells, which in turn derive from secondary lymphangiogenic sprouts from the posterior cardinal vein. Morpholino knockdown of synectin in zebrafish impaired formation of the thoracic duct, due to selective defects in lymphangiogenic but not angiogenic sprouting. Synectin genetically interacted with Vegfr3 and neuropilin-2a in regulating lymphangiogenesis. Silencing of synectin in tadpoles caused lymphatic defects due to an underdevelopment and impaired migration of Prox-1(+) lymphatic endothelial cells. Molecular analysis further revealed that synectin regulated Sox18-induced expression of Prox-1 and vascular endothelial growth factor C-induced migration of lymphatic endothelial cells in vitro. These findings reveal a novel role for synectin in lymphatic development.

We report here that junctional adhesion molecule (JAM) interacts with calcium/calmodulin-dependent serine protein kinase (CASK), a protein related to membrane-associated guanylate kinases. In Caco-2 cells, JAM and CASK were coprecipitated and found to colocalize at intercellular contacts along the lateral surface of the plasma membrane. Association of JAM with CASK requires the PSD95/dlg/ZO-1 (PDZ) domain of CASK and the putative PDZ-binding motif Phe-Leu-Val(COOH) in the cytoplasmic tail of JAM. Temporal dissociation in the junctional localization of the two proteins suggests that the association with CASK is not required for recruiting JAM to intercellular junctions. Compared with mature intercellular contacts, junction assembly was characterized by both enhanced solubility of CASK in Triton X-100 and reduced amounts of Triton-insoluble JAM-CASK complexes. We propose that JAM association with CASK is modulated during junction assembly, when CASK is partially released from its cytoskeletal associations.

Vascular endothelial cadherin, VE-cadherin, mediates adhesion between endothelial cells and may affect vascular morphogenesis via intracellular signaling, but the nature of these signals remains unknown. Here, targeted inactivation (VEC-/-) or truncation of the beta-catenin-binding cytosolic domain (VECdeltaC/deltaC) of the VE-cadherin gene was found not to affect assembly of endothelial cells in vascular plexi, but to impair their subsequent remodeling and maturation, causing lethality at 9.5 days of gestation. Deficiency or truncation of VE-cadherin induced endothelial apoptosis and abolished transmission of the endothelial survival signal by VEGF-A to Akt kinase and Bcl2 via reduced complex formation with VEGF receptor-2, beta-catenin, and phosphoinositide 3 (PI3)-kinase. Thus, VE-cadherin/ beta-catenin signaling controls endothelial survival.