44 research outputs found
Evidence for anti-angiogenic and pro-survival functions of the cerebral cavernous malformation protein 3
Mutations in CCM1, CCM2, or CCM3 lead to cerebral cavernous malformations, one of the most common hereditary vascular diseases of the brain. Endothelial cells within these lesions are the main disease compartments. Here, we show that adenoviral CCM3 expression inhibits endothelial cell migration, proliferation, and tube formation while downregulation of endogenous CCM3 results in increased formation of tube-like structures. Adenoviral CCM3 expression does not induce apoptosis under normal endothelial cell culture conditions but protects endothelial cells from staurosporine-induced cell death. Tyrosine kinase activity profiling suggests that CCM3 supports PDPK-1/Akt-mediated endothelial cell quiescence and survival
The cerebral cavernous malformation 3 gene is necessary for senescence induction.
Mutations in cerebral cavernous malformation 3 gene are known to result in development of vascular malformations and have recently been proposed to also give rise to meningiomas. We report in this study that lack of CCM3 unexpectedly impairs the senescence response of cells, and this is related to the inability of CCM3-deficient cells to induce the C/EBPβ transcription factor and implement the senescence-associated secretory phenotype. Induction of C/EBPβ and cytokines is also impaired in the absence of CCM3 in response to cytokines in nonsenescent cells, pointing to it being a primary defect and not secondary to impaired senescence. CCM3-deficient cells also have a defect in autophagy at late passages of culture, and this defect is also not dependent on impaired senescence, as it is evident in immortal cells after nutrient starvation. Further, these two defects may be related, as enforcing autophagy in CCM3-deficient late passage cells increases C/EBPβ cytokine expression. These results broaden our knowledge on the mechanisms by which CCM3 deficiency results in disease and open new avenues of research into both CCM3 and senescence biology
Knowledge Graphs Evolution and Preservation -- A Technical Report from ISWS 2019
One of the grand challenges discussed during the Dagstuhl Seminar "Knowledge
Graphs: New Directions for Knowledge Representation on the Semantic Web" and
described in its report is that of a: "Public FAIR Knowledge Graph of
Everything: We increasingly see the creation of knowledge graphs that capture
information about the entirety of a class of entities. [...] This grand
challenge extends this further by asking if we can create a knowledge graph of
"everything" ranging from common sense concepts to location based entities.
This knowledge graph should be "open to the public" in a FAIR manner
democratizing this mass amount of knowledge." Although linked open data (LOD)
is one knowledge graph, it is the closest realisation (and probably the only
one) to a public FAIR Knowledge Graph (KG) of everything. Surely, LOD provides
a unique testbed for experimenting and evaluating research hypotheses on open
and FAIR KG. One of the most neglected FAIR issues about KGs is their ongoing
evolution and long term preservation. We want to investigate this problem, that
is to understand what preserving and supporting the evolution of KGs means and
how these problems can be addressed. Clearly, the problem can be approached
from different perspectives and may require the development of different
approaches, including new theories, ontologies, metrics, strategies,
procedures, etc. This document reports a collaborative effort performed by 9
teams of students, each guided by a senior researcher as their mentor,
attending the International Semantic Web Research School (ISWS 2019). Each team
provides a different perspective to the problem of knowledge graph evolution
substantiated by a set of research questions as the main subject of their
investigation. In addition, they provide their working definition for KG
preservation and evolution