Search results for "Wnt Signaling Pathway"
showing 10 items of 115 documents
M2 Macrophages Activate WNT Signaling Pathway in Epithelial Cells: Relevance in Ulcerative Colitis
2013
Macrophages, which exhibit great plasticity, are important components of the inflamed tissue and constitute an essential element of regenerative responses. Epithelial Wnt signalling is involved in mechanisms of proliferation and differentiation and expression of Wnt ligands by macrophages has been reported. We aim to determine whether the macrophage phenotype determines the expression of Wnt ligands, the influence of the macrophage phenotype in epithelial activation of Wnt signalling and the relevance of this pathway in ulcerative colitis. Human monocyte-derived macrophages and U937-derived macrophages were polarized towards M1 or M2 phenotypes and the expression of Wnt1 and Wnt3a was analy…
Quiescence Modulates Stem Cell Maintenance and Regenerative Capacity in the Aging Brain.
2018
The function of somatic stem cells declines with age. Understanding the molecular underpinnings of this decline is key to counteract age-related disease. Here, we report a dramatic drop in the neural stem cells (NSCs) number in the aging murine brain. We find that this smaller stem cell reservoir is protected from full depletion by an increase in quiescence that makes old NSCs more resistant to regenerate the injured brain. Once activated, however, young and old NSCs show similar proliferation and differentiation capacity. Single-cell transcriptomics of NSCs indicate that aging changes NSCs minimally. In the aging brain, niche-derived inflammatory signals and the Wnt antagonist sFRP5 induce…
Creating a conditional mutation of Wnt-1 by antisense transgenesis provides evidence that Wnt-1 is not essential for spermatogenesis.
1993
We have used mice transgenic for an antisense construct for Wnt-1 to study the role of this gene in post-meiotic sperm development. The human PGK-2 promoter provided levels of Wnt-1 antisense mRNA in testes in 5 transgenic lines greatly in excess of Wnt-1 mRNA concentrations, and Wnt-1 mRNA levels were greatly decreased in the lines, by 98% in three of them. There was a general correlation between copy number of the insert, levels of antisense RNA, and decreases in mRNA. There was little effect of the antisense transgene on fertility or testicular histology suggesting that normal levels of Wnt-1 transcript are not essential for spermatogenesis.
UNC-52/perlecan affects gonadal leader cell migrations in C. elegans hermaphrodites through alterations in growth factor signaling.
2003
0012-1606 doi: DOI: 10.1016/S0012-1606(03)00014-9; The unc-52 gene of Claenorhabditis elegans encodes a homologue of the basement membrane heparan sulfate proteoglycan perlecan. Viable alleles reduce the abundance of UNC-52 in late larval stages and increase the frequency of distal tip cell (DTC) migration defects caused by mutations disrupting the UNC-6/netrin guidance system. These unc-52 alleles do not cause circumferential DTC migration defects in an otherwise wild-type genetic background. The effects of unc-52 mutations on DTC migrations are distinct from effects on myofilament organization and can be partially suppressed by mutations in several genes encoding growth factor-like molecu…
TRTH-08. HIGH GRADE NEUROEPITHELIAL TUMOR OF THE CENTRAL NERVOUS SYSTEM WITH BCOR ALTERATION IS SENSITIVE TO IGF1R INHIBITION
2017
High grade neuroepithelial tumor of the central nervous system with BCOR alteration (CNS HGNET-BCOR) is a recently described new tumor entity which was formerly diagnosed with diverse histological diagnoses, for example as ependymoma. This tumor predominantly affects children and has a dismal prognosis. No standard therapies for this entity exist so far. Recently we described the activation of the Sonic hedgehog (SHH) and the WNT signaling pathway in this tumor and described a primary cell culture (PhKh1) isolated from a skull metastasis of a seven years old patient. We also detected a high expression of IGF2, which is known to be required for SHH signaling in medulloblastoma. IGF2 signals …
CONSERVED CELLULAR AND MOLECULAR MECHANISMS IN DEVELOPMENT
2002
This review discusses examples of conserved cellular and molecular mechansims in development, including the pathway of signal transduction between the photoreceptors R8 and R7 in Drosophila, which is compared to vulval induction in Caenorhabditis elegans. The Wg pathway in Drosophila is compared, first, to the Wnt pathway in dorsal mesoderm specification in Xenopus: second, to the same pathway in sea urchins; third, to the equivalent in the mom cascade of C. elegans; and finally, to parts of the equivalent pathway in Dictyostelium discoideum. The conserved expression of some hox genes in vertebrate limb buds and in the heads or tails of several invertebrate and vertebrate embryos is also il…
Expression profile of components of the β-catenin destruction complex in oral dysplasia and oral cancer
2021
Background Oral cancer represents the sixth most common cancer in the world and is associated with 40-50% survival at 5 years. Within oral malignancies, oral squamous cell carcinoma (OSCC) is commonly preceded by potentially malignant lesions, which, according to histopathological criteria, are referred to as oral dysplasia and their diagnosis are associated with higher rates of malignant transformation towards cancer. We recently reported that aberrant activation of the Wnt/β‑catenin pathway is due to overexpression of Wnt ligands in oral dysplasia. However, the expression of other regulators of this pathway, namely components of the β-catenin destruction complex has not been explored in o…
Loss of Dishevelleds disrupts planar polarity in ependymal motile cilia and results in hydrocephalus.
2014
Defects in ependymal (E) cells, which line the ventricle and generate cerebrospinal fluid flow through ciliary beating, can cause hydrocephalus. Dishevelled genes (Dvls) are essential for Wnt signaling, and Dvl2 has been shown to localize to the rootlet of motile cilia. Using the hGFAP-Cre;Dvl1(-/-);2(flox/flox);3(+/-) mouse, we show that compound genetic ablation of Dvls causes hydrocephalus. In hGFAP-Cre;Dvl1(-/-);2(flox/flox);3(+/-) mutants, E cells differentiated normally, but the intracellular and intercellular rotational alignments of ependymal motile cilia were disrupted. As a consequence, the fluid flow generated by the hGFAP-Cre;Dvl1(-/-);2(flox/flox);3(+/-) E cells was significant…
New molecular targets for the treatment of osteoarthritis.
2009
Osteoarthritis (OA) is a chronic degenerative joint disorder characterized by destruction of the articular cartilage, subchondral bone alterations and synovitis. Current treatments are focused on symptomatic relief but they lack efficacy to control the progression of this disease which is a leading cause of disability. Therefore, the development of effective disease-modifying drugs is urgently needed. Different initiatives are in progress to define the molecular mechanisms involved in the initiation and progression of OA. These studies support the therapeutic potential of pathways relevant in joint metabolism such as Wnt/beta-catenin, discoidin domain receptor 2 or proteinase-activated rece…
The Wnt/beta-Catenin Pathway Attenuates Experimental Allergic Airway Disease
2014
Abstract Signaling via the Wnt/β-catenin pathway plays crucial roles in embryogenesis and homeostasis of adult tissues. In the lung, the canonical Wnt/β-catenin pathway has been implicated in remodeling processes, development of emphysema, and fibrosis. However, its relevance for the modulation of allergic responses in the lung remains unclear. Using genetically modified mice with lung-specific inducible (doxycycline) Wnt-1 expression (CCSP-rtTA × tetO-Wnt1), the impact of Wnt on the development of allergic airway disease was analyzed. Overexpression of Wnt during the allergen challenge phase attenuated the development of airway inflammation in an acute model, as well as in a more therapeut…