Search results for "CDH1"

Somatic copy number alterations are associated with EGFR amplification and shortened survival in patients with primary glioblastoma.

2019

Glioblastoma (GBM) is the most common malignant primary tumor of the central nervous system. With no effective therapy, the prognosis for patients is terrible poor. It is highly heterogeneous and EGFR amplification is its most frequent molecular alteration. In this light, we aimed to examine the genetic heterogeneity of GBM and to correlate it with the clinical characteristics of the patients. For that purpose, we analyzed the status of EGFR and the somatic copy number alterations (CNAs) of a set of tumor suppressor genes and oncogenes. Thus, we found GBMs with high level of EGFR amplification, low level and with no EGFR amplification. Highly amplified tumors showed histological features of…

New Functions of APC/C Ubiquitin Ligase in the Nervous System and Its Role in Alzheimer’s Disease

2017

The E3 ubiquitin ligase Anaphase Promoting Complex/Cyclosome (APC/C) regulates important processes in cells, such as the cell cycle, by targeting a set of substrates for degradation. In the last decade, APC/C has been related to several major functions in the nervous system, including axon guidance, synaptic plasticity, neurogenesis, and neuronal survival. Interestingly, some of the identified APC/C substrates have been related to neurodegenerative diseases. There is an accumulation of some degradation targets of APC/C in Alzheimer’s disease (AD) brains, which suggests a dysregulation of the protein complex in the disorder. Moreover, recently evidence has been provided for an inactivation o…

miR‐200c and phospho‐AKT as prognostic factors and mediators of osteosarcoma progression and lung metastasis

2016

Lung metastasis is the major cause of death in osteosarcoma patients. However, molecular mechanisms underlying this metastasis remain poorly understood. To identify key molecules related with pulmonary metastasis of pediatric osteosarcomas, we analyzed high-throughput miRNA expression in a cohort of 11 primary tumors and 15 lung metastases. Results were further validated with an independent cohort of 10 primary tumors and 6 metastases. In parallel, we performed immunohistochemical analysis of activated signaling pathways in 36 primary osteosarcomas. Only phospho-AKT associated with lower overall survival in primary tumors, supporting its role in osteosarcoma progression. CTNNB1 expression a…

Narrowing the Genetic Causes of Language Dysfunction in the 1q21.1 Microduplication Syndrome

2018

The chromosome 1q21.1 duplication syndrome (OMIM# 612475) is characterized by head anomalies, mild facial dysmorphisms, and cognitive problems, including autistic features, mental retardation, developmental delay, and learning disabilities. Speech and language development are sometimes impaired, but no detailed characterization of language problems in this condition has been provided to date. We report in detail on the cognitive and language phenotype of a child who presents with a duplication in 1q21.1 (arr[hg19] 1q21.1q21.2(145,764,455-147,824,207) × 3), and who exhibits cognitive delay and behavioral disturbances. Language is significantly perturbed, being the expressive domain the most …

Aβ Induces Excitotoxicity Mediated by APC/C-Cdh1 Depletion That Can Be Prevented by Glutaminase Inhibition Promoting Neuronal Survival

2016

AbstractThe E3 ubiquitin ligase anaphase-promoting complex/cyclosome (APC/C) is activated by the fizzy-related protein homolog/CDC20-like protein 1 (cdh1) in post-mitotic neurons. Growing evidence suggests that dysregulation of APC/C-Cdh1 is involved in neurodegenerative diseases. Here we show in neurons that oligomers of amyloid beta (Aβ), a peptide related to Alzheimer’s disease, cause proteasome-dependent degradation of cdh1. This leads to a subsequent increase in glutaminase (a degradation target of APC/C-Cdh1), which causes an elevation of glutamate levels and further intraneuronal Ca2+ dysregulation, resulting in neuronal apoptosis. Glutaminase inhibition prevents glutamate excitotoxi…

2018

AbstractThe cell adhesion glycoprotein E-cadherin (CDH1) is commonly inactivated in breast tumors. Precision medicine approaches that exploit this characteristic are not available. Using perturbation screens in breast tumor cells with CRISPR/Cas9-engineered CDH1 mutations, we identified synthetic lethality between E-cadherin deficiency and inhibition of the tyrosine kinase ROS1. Data from large-scale genetic screens in molecularly diverse breast tumor cell lines established that the E-cadherin/ROS1 synthetic lethality was not only robust in the face of considerable molecular heterogeneity but was also elicited with clinical ROS1 inhibitors, including foretinib and crizotinib. ROS1 inhibitor…

Estudio de la migración neuronal de las células nerviosas de la SVZ en la enfermedad de Alzheimer

2021

En el cerebro adulto de la mayoría de los mamíferos el nicho neurogénico con mayor capacidad neurogénica es la zona ventricular-subventricular (V-SVZ). Esta región se encuentra distribuida a lo largo de las paredes de los ventrículos laterales. La capacidad neurogénica que presenta esta región se debe a la presencia de las denominadas células B. Además nos encontramos con otros tipos celulares como son las células tipo C o progenitores intermedios, las tipo A o migradoras y las tipo E o células ependimarias. Las células tipo B son capaces de dar lugar a las células tipo C que finalmente generan las células tipo A. En condiciones fisiológicas, las células tipo A migran principalmente hasta l…

Cadherin 23 is a component of the transient lateral links in the developing hair bundles of cochlear sensory cells

2005

AbstractCadherin 23 is required for normal development of the sensory hair bundle, and recent evidence suggests it is a component of the tip links, filamentous structures thought to gate the hair cells' mechano-electrical transducer channels. Antibodies against unique peptide epitopes were used to study the properties of cadherin 23 and its spatio-temporal expression patterns in developing cochlear hair cells. In the rat, intra- and extracellular domain epitopes are readily detected in the developing hair bundle between E18 and P5, and become progressively restricted to the distal tip of the hair bundle. From P13 onwards, these epitopes are no longer detected in hair bundles, but immunoreac…

The APC/C cofactor Cdh1 prevents replicative stress and p53-dependent cell death in neural progenitors

2013

The E3-ubiquitin ligase APC/C-Cdh1 is essential for endoreduplication but its relevance in the mammalian mitotic cell cycle is still unclear. Here we show that genetic ablation of Cdh1 in the developing nervous system results in hypoplastic brain and hydrocephalus. These defects correlate with enhanced levels of Cdh1 substrates and increased entry into the S phase in neural progenitors. However, cell division is prevented in the absence of Cdh1 due to hyperactivation of cyclin-dependent kinases, replicative stress, induction of p53, G2 arrest and apoptotic death of these progenitor cells. Concomitant ablation of p53 rescues apoptosis but not replicative stress, resulting in the presence of …

Myosin VIIa, harmonin and cadherin 23, three Usher I gene products that cooperate to shape the sensory hair cell bundle

2002

Deaf-blindness in three distinct genetic forms of Usher type I syndrome (USH1) is caused by defects in myosin VIIa, harmonin and cadherin 23. Despite being critical for hearing, the functions of these proteins in the inner ear remain elusive. Here we show that harmonin, a PDZ domain-containing protein, and cadherin 23 are both present in the growing stereocilia and that they bind to each other. Moreover, we demonstrate that harmonin b is an F-actin-bundling protein, which is thus likely to anchor cadherin 23 to the stereocilia microfilaments, thereby identifying a novel anchorage mode of the cadherins to the actin cytoskeleton. Moreover, harmonin b interacts directly with myosin VIIa, and i…