RESUMO
BACKGROUND: CDH1 and CTNNA1 remain as the main genes for hereditary gastric cancer. However, they only explain a small fraction of gastric cancer cases with suspected inherited basis. In this study, we aimed to identify new hereditary genes for early-onset gastric cancer patients (EOGC; < 50 years old). METHODS: After germline exome sequencing in 20 EOGC patients and replication of relevant findings by gene-panel sequencing in an independent cohort of 152 patients, CTNND1 stood out as an interesting candidate gene, since its protein product (p120ctn) directly interacts with E-cadherin. We proceeded with functional characterization by generating two knockout CTNND1 cellular models by gene editing and introducing the detected genetic variants using a lentiviral delivery system. We assessed ß-catenin and E-cadherin levels, cell detachment, as well as E-cadherin localization and cell-to-cell interaction by spheroid modeling. RESULTS: Three CTNND1 germline variants [c.28_29delinsCT, p.(Ala10Leu); c.1105C > T, p.(Pro369Ser); c.1537A > G, p.(Asn513Asp)] were identified in our EOGC cohorts. Cells encoding CTNND1 variants displayed altered E-cadherin levels and intercellular interactions. In addition, the p.(Pro369Ser) variant, located in a key region in the E-cadherin/p120ctn binding domain, showed E-cadherin mislocalization. CONCLUSIONS: Defects in CTNND1 could be involved in germline predisposition to gastric cancer by altering E-cadherin and, consequently, cell-to-cell interactions. In the present study, CTNND1 germline variants explained 2% (3/172) of the cases, although further studies in larger external cohorts are needed.
Assuntos
Caderinas , Cateninas , delta Catenina , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Neoplasias Gástricas , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Humanos , Masculino , Cateninas/genética , Cateninas/metabolismo , Feminino , Pessoa de Meia-Idade , Adulto , Caderinas/genética , Comunicação Celular , Idade de Início , Antígenos CDRESUMO
Prostate cancer (PCa) is the second leading cause of death in males. It has been reported that δ-catenin expression is upregulated during the late stage of prostate cancer. Palmitoylation promotes protein transport to the cytomembrane and regulates protein localization and function. However, the effect of δ-catenin palmitoylation on the regulation of cancer remains unknown. In this study, we utilized prostate cancer cells overexpressing mutant δ-catenin (J6A cells) to induce a depalmitoylation phenotype and investigate its effect on prostate cancer. Our results indicated that depalmitoylation of δ-catenin not only reduced its membrane expression but also promoted its degradation in the cytoplasm, resulting in a decrease in the effect of EGFR and E-cadherin signaling. Consequently, depalmitoylation of δ-catenin reduced the proliferation and metastasis of prostate cancer cells. Our findings provide novel insights into potential therapeutic strategies for controlling the progression of prostate cancer through palmitoylation-based targeting of δ-catenin.
Assuntos
Caderinas , Cateninas , Proliferação de Células , delta Catenina , Progressão da Doença , Lipoilação , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Cateninas/metabolismo , Cateninas/genética , Linhagem Celular Tumoral , Caderinas/metabolismo , Caderinas/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Transdução de Sinais , Animais , Movimento Celular , Regulação Neoplásica da Expressão GênicaRESUMO
CTNND2 encodes δ-catenin, a component of an adherens junction complex, and plays an important role in neuronal structure and function. To date, only heterozygous loss-of-function CTNND2 variants have been associated with mild neurodevelopmental delay and behavioral anomalies, a condition, which we named Rauch-Azzarello syndrome. Here, we report three siblings of a consanguineous family of Syrian descent with a homozygous deletion encompassing the last 19 exons of CTNND2 predicted to disrupt the transcript. All presented with severe neurodevelopmental delay with absent speech, profound motor delay, stereotypic behavior, microcephaly, short stature, muscular hypotonia with lower limb hypertonia, and variable eye anomalies. The parents and the fourth sibling were heterozygous carriers of the deletion and exhibited mild neurodevelopmental impairment resembling that of the previously described heterozygous individuals. The present study unveils a severe manifestation of CTNND2-associated Rauch-Azzarello syndrome attributed to biallelic loss-of-function aberrations, clinically distinct from the already described mild presentation of heterozygous individuals. Furthermore, we demonstrate novel clinical features in homozygous individuals that have not been reported in heterozygous cases to date.
Assuntos
delta Catenina , Transtornos do Neurodesenvolvimento , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Alelos , Cateninas/genética , Consanguinidade , Homozigoto , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/patologia , Linhagem , Fenótipo , Deleção de Sequência/genéticaRESUMO
Force transmission at cell-cell junctions critically regulates embryogenesis, tissue homeostasis, and diseases including cancer. The cadherin-catenin linkage has been considered the keystone of junctional force transmission, but new findings challenge this paradigm, arguing instead that the nectin-afadin linkage plays the more important role in mature junctions in the intestinal epithelium.
Assuntos
Junções Intercelulares , Proteínas dos Microfilamentos , Nectinas , Caderinas/metabolismo , Cateninas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Nectinas/metabolismo , Junções Intercelulares/química , HumanosRESUMO
Valproic acid (VPA) is an effective and commonly prescribed drug for epilepsy and bipolar disorder. However, children born from mothers treated with VPA during pregnancy exhibit an increased incidence of autism spectrum disorder (ASD). Although VPA may impair brain development at the cellular level, the mechanism of VPA-induced ASD has not been completely addressed. A previous study has found that VPA treatment strongly reduces δ-catenin mRNA levels in cultured human neurons. δ-catenin is important for the control of glutamatergic synapses and is strongly associated with ASD. VPA inhibits dendritic morphogenesis in developing neurons, an effect that is also found in neurons lacking δ-catenin expression. We thus hypothesize that prenatal exposure to VPA significantly reduces δ-catenin levels in the brain, which impairs glutamatergic synapses to cause ASD. Here, we found that prenatal exposure to VPA markedly reduced δ-catenin levels in the brain of mouse pups. VPA treatment also impaired dendritic branching in developing mouse cortical neurons, which was partially reversed by elevating δ-catenin expression. Prenatal VPA exposure significantly reduced synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor levels and postsynaptic density 95 (PSD95) in the brain of mouse pups, indicating dysfunctions in glutamatergic synaptic transmission. VPA exposure also significantly altered ultrasonic vocalization (USV) in newly born pups when they were isolated from their nest. Moreover, VPA-exposed pups show impaired hypothalamic response to isolation, which is required to produce animals' USVs following isolation from the nest. Therefore, these results suggest that VPA-induced ASD pathology can be mediated by the loss of δ-catenin functions.
Assuntos
Animais Recém-Nascidos , Efeitos Tardios da Exposição Pré-Natal , Ácido Valproico , Vocalização Animal , Animais , Ácido Valproico/farmacologia , Ácido Valproico/toxicidade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Feminino , Vocalização Animal/efeitos dos fármacos , Vocalização Animal/fisiologia , Camundongos , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Cateninas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Receptores de AMPA/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Transtorno do Espectro Autista/induzido quimicamente , Transtorno do Espectro Autista/metabolismoRESUMO
The epicardium is integral to cardiac development and facilitates endogenous heart regeneration and repair. While miR-194-3p is associated with cellular migration and invasion, its impact on epicardial cells remains uncharted. In this work we use gain-of-function and loss-of-function methodologies to investigate the function of miR-194-3p in cardiac development. We culture embryonic epicardial cells in vitro and subject them to transforming growth factor ß (TGF-ß) treatment to induce epithelial-mesenchymal transition (EMT) and monitor miR-194-3p expression. In addition, the effects of miR-194-3p mimics and inhibitors on epicardial cell development and changes in EMT are investigated. To validate the binding targets of miR-194-3p and its ability to recover the target gene-phenotype, we produce a mutant vector p120-catenin-3'UTR-MUT. In epicardial cells, TGF-ß-induced EMT results in a notable overexpression of miR-194-3p. The administration of miR-194-3p mimics promotes EMT, which is correlated with elevated levels of mesenchymal markers. Conversely, miR-194-3p inhibitor attenuates EMT. Further investigations reveal a negative correlation between miR-194-3p and p120-catenin, which influences ß-catenin level in the cell adhesion pathway. The suppression of EMT caused by the miR-194-3p inhibitor is balanced by silencing of p120-catenin. In conclusion, miR-194-3p directly targets p120-catenin and modulates its expression, which in turn alters ß-catenin expression, critically influencing the EMT process in the embryonic epicardial cells via the cell adhesion mechanism.
Assuntos
Cateninas , Transição Epitelial-Mesenquimal , MicroRNAs , Pericárdio , Transdução de Sinais , beta Catenina , Transição Epitelial-Mesenquimal/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , beta Catenina/metabolismo , beta Catenina/genética , Pericárdio/metabolismo , Pericárdio/citologia , Pericárdio/embriologia , Camundongos , Cateninas/metabolismo , Cateninas/genética , delta Catenina , Fator de Crescimento Transformador beta/metabolismo , Células CultivadasRESUMO
Epilepsy is a neurological disorder characterised by unprovoked, repetitive seizures caused by abnormal neuronal firing. The Wnt/ß-Catenin signalling pathway is involved in seizure-induced neurogenesis, aberrant neurogenesis, neuroinflammation, and hyperexcitability associated with epileptic disorder. Wnt/ß-Catenin signalling is crucial for early brain development processes including neuronal patterning, synapse formation, and N-methyl-d-aspartate receptor (NMDAR) regulation. Disruption of molecular networks such as Wnt/ß-catenin signalling in epilepsy could offer encouraging anti-epileptogenic targets. So, with a better understanding of the canonical Wnt/-Catenin pathway, we highlight in this review the important elements of Wnt/-Catenin signalling specifically in Mesial Temporal Lobe Epilepsy (MTLE) for potential therapeutic targets.
Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Humanos , Epilepsia do Lobo Temporal/induzido quimicamente , beta Catenina/metabolismo , Doenças Neuroinflamatórias , Epilepsia/metabolismo , Neurogênese , Cateninas/metabolismo , Hipocampo/metabolismoRESUMO
BACKGROUND: Liver cancer is one of the most lethal malignancies for humans. The treatment options for advanced-stage liver cancer remain limited. A new treatment is urgently needed to reduce the mortality of the disease. METHODS: In this report, we developed a technology for mutation site insertion of a suicide gene (herpes simplex virus type 1- thymidine kinase) based on type II CRISPR RNA-guided endonuclease Cas9-mediated genome editing to treat liver cancers. RESULTS: We applied the strategy to 3 different mutations: S45P mutation of catenin beta 1, chromosome breakpoint of solute carrier family 45 member 2-alpha-methylacyl-CoA racemase gene fusion, and V235G mutation of SAFB-like transcription modulator. The results showed that the herpes simplex virus type 1-thymidine kinase insertion rate at the S45P mutation site of catenin beta 1 reached 77.8%, while the insertion rates at the breakpoint of solute carrier family 45 member 2 - alpha-methylacyl-CoA racemase gene fusion were 95.1%-98.7%, and the insertion at V235G of SAFB-like transcription modulator was 51.4%. When these targeting reagents were applied to treat mouse spontaneous liver cancer induced by catenin beta 1S45P or solute carrier family 45 member 2-alpha-methylacyl-CoA racemase, the mice experienced reduced tumor burden and increased survival rate. Similar results were also obtained for the xenografted liver cancer model: Significant reduction of tumor volume, reduction of metastasis rate, and improved survival were found in mice treated with the targeting reagent, in comparison with the control-treated groups. CONCLUSIONS: Our studies suggested that mutation targeting may hold promise as a versatile and effective approach to treating liver cancers.
Assuntos
Herpesvirus Humano 1 , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Timidina Quinase/genética , Sistemas CRISPR-Cas/genética , Herpesvirus Humano 1/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Cateninas , Mutação/genéticaRESUMO
Objective: To investigate the clinicopathological features and molecular characteristics of ß-catenin-deficient colorectal cancer. Methods: The clinical, pathological and molecular features of 11 colorectal cancers with ß-catenin protein loss diagnosed at the 960th Hospital of People's Liberation Army of China, from January 2012 to November 2022 were analyzed. Results: Among the 11 patients, 3 were males and 8 were females. Their age ranged from 43 to 74 years, with the median age of 59 years. Six were in the left colon and 5 were in the right colon. One of the 11 cases had lymph node metastasis, 10 cases were well and moderately differentiated adenocarcinoma, and 1 was mucinous adenocarcinoma. Eight cases were of TNM stage T4, 2 of T1 stage and 1 of Tis stage. ß-catenin protein was not detected using immunohistochemistry. Sanger sequencing revealed the presence of fragment-deletion mutation in exon 3 of CTNNB1 gene, resulting in loss of ß-catenin protein expression. Conclusion: ß-catenin deficiency is present in a small number of colorectal cancers and may be associated with exon 3 mutations of CTNNB1 gene.
Assuntos
Adenocarcinoma , Neoplasias Colorretais , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adenocarcinoma/genética , beta Catenina/genética , Cateninas , Neoplasias Colorretais/genética , ÉxonsRESUMO
During epithelial morphogenesis, the apical junctions connecting cells must remodel as cells change shape and make new connections with their neighbors. In the C. elegans embryo, new apical junctions form when epidermal cells migrate and seal with one another to encase the embryo in skin ('ventral enclosure'), and junctions remodel when epidermal cells change shape to squeeze the embryo into a worm shape ('elongation'). The junctional cadherin-catenin complex (CCC), which links epithelial cells to each other and to cortical actomyosin, is essential for C. elegans epidermal morphogenesis. RNAi genetic enhancement screens have identified several genes encoding proteins that interact with the CCC to promote epidermal morphogenesis, including the scaffolding protein Afadin (AFD-1), whose depletion alone results in only minor morphogenesis defects. Here, by creating a null mutation in afd-1, we show that afd-1 provides a significant contribution to ventral enclosure and elongation on its own. Unexpectedly, we find that afd-1 mutant phenotypes are strongly modified by diet, revealing a previously unappreciated parental nutritional input to morphogenesis. We identify functional interactions between AFD-1 and the CCC by demonstrating that E-cadherin is required for the polarized distribution of AFD-1 to cell contact sites in early embryos. Finally, we show that afd-1 promotes the enrichment of polarity regulator, and CCC-interacting protein, PAC-1/ARHGAP21 to cell contact sites, and we identify genetic interactions suggesting that afd-1 and pac-1 regulate epidermal morphogenesis at least in part through parallel mechanisms. Our findings reveal that C. elegans AFD-1 makes a significant contribution to epidermal morphogenesis and functionally interfaces with core and associated CCC proteins.
Assuntos
Caderinas , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Epiderme , Morfogênese , Animais , Caderinas/metabolismo , Caderinas/genética , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Cateninas/metabolismo , Cateninas/genética , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Epiderme/embriologia , Proteínas Ativadoras de GTPase/metabolismo , Proteínas Ativadoras de GTPase/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/genéticaRESUMO
Adhesion between stem cells and their niche provides stable anchorage and signaling cues to sustain properties such as quiescence. Skeletal muscle stem cells (MuSCs) adhere to an adjacent myofiber via cadherin-catenin complexes. Previous studies on N- and M-cadherin in MuSCs revealed that although N-cadherin is required for quiescence, they are collectively dispensable for MuSC niche localization and regenerative activity. Although additional cadherins are expressed at low levels, these findings raise the possibility that cadherins are unnecessary for MuSC anchorage to the niche. To address this question, we conditionally removed from MuSCs ß- and γ-catenin, and, separately, αE- and αT-catenin, factors that are essential for cadherin-dependent adhesion. Catenin-deficient MuSCs break quiescence similarly to N-/M-cadherin-deficient MuSCs, but exit the niche and are depleted. Combined in vivo, ex vivo and single cell RNA-sequencing approaches reveal that MuSC attrition occurs via precocious differentiation, re-entry to the niche and fusion to myofibers. These findings indicate that cadherin-catenin-dependent adhesion is required for anchorage of MuSCs to their niche and for preservation of the stem cell compartment. Furthermore, separable cadherin-regulated functions govern niche localization, quiescence and MuSC maintenance.
Assuntos
Caderinas , Nicho de Células-Tronco , Nicho de Células-Tronco/genética , Caderinas/genética , Caderinas/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Transdução de Sinais , Cateninas/genética , Cateninas/metabolismo , Músculo Esquelético/metabolismo , Adesão Celular/genéticaRESUMO
The toxic effects of nanoparticles-silver oxide (Ag2 O) limited its use. However, loading Ag2 O nanoparticles into titanium dioxide (TiO2 ) nanotubes (Ag2 O-TiO2 -NTs) has more efficient biological activity and safety. The aim of this study was to observe the effect of Ag2 O-TiO2 -NTs on osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and its mechanism. The enzyme activity of lactate dehydrogenase (LDH) and the expression of RUNX family transcription factor 2 (Runx2), OPN, OCN in BMSCs were detected by quantitative real time polymerase chain reaction. At 14 days of induction, the mineralization ability and alkaline phosphatase (ALP) activity of cells in each group were observed by Alizarin Red S staining and ALP staining. In addition, the protein levels of tumor necrosis factor-α (TNF-α) and ß-catenin in BMSCs of each group were observed by western blot. After 14 days of the induction, the mineralization ability and ALP activity of BMSCs in the Ag2 O-TiO2 -NTs group were significantly enhanced compared with those in the Ag2 O and TiO2 groups. Western blot analysis showed that the BMSCs in the Ag2 O-TiO2 -NTs group exhibited much lower protein level of TNF-α and higher protein level of ß-catenin than those in the Ag2 O and TiO2 groups.Ag2 O-TiO2 -NTs enhance the osteogenic activity of BMSCs by modulating TNF-α/ß-catenin signaling.
Assuntos
Células-Tronco Mesenquimais , Osteogênese , Fator de Necrose Tumoral alfa/metabolismo , beta Catenina/metabolismo , Cateninas/metabolismo , Cateninas/farmacologia , Medula Óssea/metabolismo , Células Cultivadas , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Células da Medula Óssea/metabolismoRESUMO
BACKGROUND: CircRNAs and miRNAs are involved in the progression of tumor. CircMCTP2 is considered as a novel tumor promoter. However, the exact functions of circMCTP2 in bladder cancer are still unclear. This study was designed to explore the underlying mechanisms of circMCTP2-modulated tumor development in bladder cancer. METHODS: The present study is an original research. The levels of circMCTP2 in a total of 39 bladder cancer specimens and cell lines were determined by RT-qPCR. The expression of FZD8 in T24 and RT-4 cells treated with miR-99a-5p mimics were examined using western blotting. In addition, the proliferative, migrative and invasive abilities of transfected cells were determined by CCK8 and Transwell assays. Furthermore, the apoptosis of transfected cells was evaluated using flow cytometry. Dual luciferase reporter assay was performed to elucidate the relationship between miR-99a-5p and circMCTP2/FZD8. RESULTS: The levels of circMCTP2 were elevated in bladder cancer samples and cells, and this was related to worse survival rate. Downregulation of circMCTP2 suppressed growth and metastasis of cells, whereas the apoptotic rate of cells was enhanced. The levels of miR-99a-5rp was elevated after the downregulation of circMCTP2. Moreover, reverse correlation between the expression of miR-99a-5p and circMCTP2 was revealed in bladder cancer specimens. Additionally, FZD8 was the putative target of miR-99a-5p and the mimics of miR-99a-5p inhibited the proliferation, migration and invasion of bladder cancer cells via the FZD8/Wnt-b-catenin axis. Moreover, circMCTP2 regulated the growth and metastasis of bladder cancer cells potentially through regulating the miR-99a-5p/FZD8/Wnt-b-catenin axis. In summary, circMCTP2 was considered as an oncogenic factor through regulating the miR-99a-5p/FZD8/Wnt-b-catenin axis. CONCLUSIONS: This novel signaling could regulate the biological behaviours of bladder cancer cells, and these findings highlighted circMCTP2 as a critical target for treating bladder cancer.
Assuntos
MicroRNAs , Neoplasias da Bexiga Urinária , Humanos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Cateninas/metabolismoRESUMO
Canonical Wnt and sphingosine-1-phosphate (S1P) signaling pathways are highly conserved systems that contribute to normal vertebrate development, with key consequences for immune, nervous, and cardiovascular system function; despite these functional overlaps, little is known about Wnt/ß-catenin-S1P cross-talk. In the vascular system, both Wnt/ß-catenin and S1P signals affect vessel maturation, stability, and barrier function, but information regarding their potential coordination is scant. We report an instance of functional interaction between the two pathways, including evidence that S1P receptor 1 (S1PR1) is a transcriptional target of ß-catenin. By studying vascular smooth muscle cells and arterial injury response, we find a specific requirement for the ß-catenin carboxyl terminus, which acts to induce S1PR1, and show that this interaction is essential for vascular remodeling. We also report that pharmacological inhibition of the ß-catenin carboxyl terminus reduces S1PR1 expression, neointima formation, and atherosclerosis. These findings provide mechanistic understanding of how Wnt/ß-catenin and S1P systems collaborate during vascular remodeling and inform strategies for therapeutic manipulation.
Assuntos
Aterosclerose , Cateninas , Lisofosfolipídeos , Esfingosina/análogos & derivados , Humanos , Cateninas/metabolismo , beta Catenina/metabolismo , Remodelação Vascular , Transdução de SinaisRESUMO
The study aimed to investigate the regulatory mechanism of intracellular tension signaling in endplate chondrocytes and its impact on extracellular matrix synthesis. Human endplate chondrocytes were subjected to tension load using Flexcell FX-5000™, and changes in phenotype, morphology, and the expression of Hippo signaling pathway and α-Catenin were assessed through various techniques. Through the overexpression of YAP and inhibition of α-Catenin, the study clarified the intracellular tension signaling pathway and its regulation of extracellular matrix synthesis in endplate cartilage. In vitro-cultured human endplate chondrocytes significantly suppressed phenotype-related genes and proteins, accompanied by distinct changes in cytoskeleton morphology. Tension activation resulted in the substantial activation of the Hippo pathway, increased phosphorylation of YAP, and reduced nuclear translocation of YAP. YAP overexpression alleviated the inhibitory effect of tension on extracellular matrix synthesis in endplate chondrocytes. Tension also upregulated the expression of α-Catenin in endplate chondrocytes, which was attenuated by inhibiting α-Catenin expression, thereby reducing the impact of tension on cytoskeletal morphology and YAP nuclear translocation. Taken together, the α-Catenin/actin skeleton/Hippo-coupled network is a crucial signaling pathway for tension signaling in endplate chondrocytes, providing potential therapeutic targets for the treatment of endplate cartilage degeneration.
Assuntos
Condrócitos , Via de Sinalização Hippo , Humanos , Condrócitos/metabolismo , Actinas/metabolismo , alfa Catenina/genética , alfa Catenina/metabolismo , Cateninas/metabolismo , Cartilagem/metabolismo , Fenótipo , Esqueleto/metabolismoRESUMO
The CTNNB1 gene, encoding ß-catenin, is frequently mutated in hepatocellular carcinoma (HCC, â¼30%) and in hepatoblastoma (HB, >80%), in which DLK1/DIO3 locus induction is correlated with CTNNB1 mutations. Here, we aim to decipher how sustained ß-catenin activation regulates DLK1/DIO3 locus expression and the role this locus plays in HB and HCC development in mouse models deleted for Apc (ApcΔhep) or Ctnnb1-exon 3 (ß-cateninΔExon3) and in human CTNNB1-mutated hepatic cancer cells. We identified an enhancer site bound by TCF-4/ß-catenin complexes in an open conformation upon sustained ß-catenin activation (DLK1-Wnt responsive element [WRE]) and increasing DLK1/DIO3 locus transcription in ß-catenin-mutated human HB and mouse models. DLK1-WRE editing by CRISPR-Cas9 approach impaired DLK1/DIO3 locus expression and slowed tumor growth in subcutaneous CTNNB1-mutated tumor cell grafts, ApcΔhep HB and ß-cateninΔExon3 HCC. Tumor growth inhibition resulted either from increased FADD expression and subsequent caspase-3 cleavage in the first case or from decreased expression of cell cycle actors regulated by FoxM1 in the others. Therefore, the DLK1/DIO3 locus is an essential determinant of FoxM1-dependent cell proliferation during ß-catenin-driven liver tumorigenesis. Targeting the DLK1-WRE enhancer to silence the DLK1/DIO3 locus might thus represent an interesting therapeutic strategy to restrict tumor growth in primary liver cancers with CTNNB1 mutations.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , beta Catenina/genética , beta Catenina/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Cateninas/genética , Cateninas/metabolismo , Proliferação de Células/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Regulação para CimaRESUMO
BACKGROUND: Lung hypoplasia contributes to congenital diaphragmatic hernia (CDH) associated morbidity and mortality. Changes in lung wingless-type MMTV integration site family member (Wnt)-signalling and its downstream effector beta-catenin (CTNNB1), which acts as a transcription coactivator, exist in animal CDH models but are not well characterized in humans. We aim to identify changes to Wnt-signalling gene expression in human CDH lungs and hypothesize that pathway expression will be lower than controls. METHODS: We identified 51 CDH cases and 10 non-CDH controls with archival formalin-fixed paraffin-embedded (FFPE) autopsy lung tissue from 2012 to 2022. 11 liveborn CDH cases and an additional two anterior diaphragmatic hernias were excluded from the study, leaving 38 CDH cases. Messenger ribonucleic acid (mRNA) expression of Wnt-signalling effectors WNT2B and CTNNB1 was determined for 19 CDH cases and 9 controls. A subset of CDH cases and controls lung sections were immunostained for ß-catenin. Clinical variables were obtained from autopsy reports. RESULTS: Median gestational age was 21 weeks. 81% (n = 31) of hernias were left-sided. 47% (n = 18) were posterolateral. Liver position was up in 81% (n = 31) of cases. Defect size was Type C or D in 58% (n = 22) of cases based on autopsy photos, and indeterminable in 42% (n = 16) of cases. WNT2B and CTNNB1 mRNA expression did not differ between CDH and non-CDH lungs. CDH lungs had fewer interstitial cells expressing ß-catenin protein than non-CDH lungs (13.2% vs 42.4%; p = 0.006). CONCLUSION: There appear to be differences in the abundance and/or localization of ß-catenin proteins between CDH and non-CDH lungs. LEVEL OF EVIDENCE: Level III. TYPE OF STUDY: Case-Control Study.
Assuntos
Hérnias Diafragmáticas Congênitas , Animais , Humanos , Lactente , beta Catenina/genética , beta Catenina/metabolismo , Estudos de Casos e Controles , Cateninas/metabolismo , Modelos Animais de Doenças , Hérnias Diafragmáticas Congênitas/patologia , Pulmão/anormalidades , Éteres Fenílicos/metabolismo , RNA Mensageiro/metabolismoRESUMO
INTRODUCTION: Vascular dementia (VaD) is a common type of dementia. The aim of this study was to investigate the cellular and molecular mechanism of conditioned medium (CM) in VaD. MATERIAL AND METHODS: The rats were divided into four groups of control (n = 9), sham-operation (n = 10), VaD with vehicle (n = 9), and VaD with CM (n = 12) that received CM on days 4, 14, and 24 after 2VO. Before sacrificing the rats, cognitive performance was assessed through the open-field (OP), passive-avoidance, and Morris-water maze. The field-potential recording was used to investigate basal synaptic transmission (BST) and long-term potentiation (LTP). Subsequently, the hippocampus was dissected, and real-time PCR was used to quantify the expression levels of ß1-catenin, insulin-like growth factor-1 (IGF-1), transforming growth factor-beta (TGF-ß), glycogen synthase kinase-3ß (GSK-3ß), postsynaptic density protein 95 (PSD-95), and NR2B genes. RESULTS: The results indicated impaired performance in behavioral tests in 2VO rats, coupled with reductions in BST and LTP induction. The expression levels of ß1-catenin, IGF-1, PSD-95, and TGF-ß genes decreased, whereas NR2B and GSK-3ß expression increased. Treatment with CM restores the expression of PSD-95 and GSK-3ß as well as fear-memory, spatial learning, and grooming number without a positive effect on memory retrieval, time spent on the periphery and center of OP. The BST recovered upon administration of CM but, the LTP induction was still impaired. CONCLUSION: The recovery of BST in VaD rats appears to be the most important outcome of this study which is caused by the improvement of gene expression and leads to the restoration of fear memory.
Assuntos
Demência Vascular , Animais , Ratos , Cateninas/metabolismo , Cognição , Meios de Cultivo Condicionados/farmacologia , Proteína 4 Homóloga a Disks-Large , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Aprendizagem em Labirinto , Ratos Sprague-Dawley , Células-Tronco/metabolismo , Transmissão Sináptica , Fator de Crescimento Transformador beta/metabolismoRESUMO
Cell-cell apical junctions of epithelia consist of multiprotein complexes that organize as belts regulating cell-cell adhesion, permeability, and mechanical tension: the tight junction (zonula occludens), the zonula adherens (ZA), and the macula adherens. The prevailing dogma is that at the ZA, E-cadherin and catenins are lined with F-actin bundles that support and transmit mechanical tension between cells. Using super-resolution microscopy on human intestinal biopsies and Caco-2 cells, we show that two distinct multiprotein belts are basal of the tight junctions as the intestinal epithelia mature. The most apical is populated with nectins/afadin and lined with F-actin; the second is populated with E-cad/catenins. We name this dual-belt architecture the zonula adherens matura. We find that the apical contraction apparatus and the dual-belt organization rely on afadin expression. Our study provides a revised description of epithelial cell-cell junctions and identifies a module regulating the mechanics of epithelia.
Assuntos
Actinas , Junções Aderentes , Humanos , Junções Aderentes/metabolismo , Actinas/metabolismo , Células CACO-2 , Caderinas/genética , Caderinas/metabolismo , Junções Intercelulares/metabolismo , Junções Íntimas/metabolismo , Cateninas/metabolismo , Células Epiteliais/metabolismoRESUMO
BACKGROUND: Tubulointerstitial kidney disease associated microenvironmental dysregulation, like acidification, inflammation and fibrosis, affects tubule cells and fibroblasts. Micromilieu homeostasis influences intracellular signaling and intercellular crosstalk. Cell-cell communication in turn modulates the interstitial microenvironment. We assessed the impact of acidosis on inflammatory and fibrotic responses in proximal tubule cells and fibroblasts as a function of cellular crosstalk. Furthermore, cellular signaling pathways involved were identified. METHODS: HK-2 (human proximal tubule) and CCD-1092Sk (human fibroblasts), in mono and coculture, were exposed to acidic or control media for 3 or 48 h. Protein expression of inflammation markers (TNF, TGF-ß and COX-2), dedifferentiation markers (N-cadherin, vinculin, ß-catenin and vimentin), fibrosis markers (collagen III and fibronectin) and phospho- as well as total MAPK levels were determined by western blot. Secreted collagen III and fibronectin were measured by ELISA. The impact of MAPK activation was assessed by pharmacological intervention. In addition, necrosis, apoptosis and epithelial permeability were determined. RESULTS: Independent of culture conditions, acidosis caused a decrease of COX-2, vimentin and fibronectin expression in proximal tubule cells. Only in monoculture, ß-Catenin expression decreased and collagen III expression increased in tubule cells during acidosis. By contrast, in coculture collagen III protein expression of tubule cells was reduced. In fibroblasts acidosis led to an increase of TNF, COX-2, vimentin, vinculin, N-cadherin protein expression and a decrease of TGF-ß expression exclusively in coculture. In monoculture, expression of COX-2 and fibronectin was reduced. Collagen III expression of fibroblasts was reduced by acidosis independent of culture conditions. In coculture, acidosis enhanced phosphorylation of ERK1/2, JNK1/2 and p38 transiently in proximal tubule cells. In fibroblasts, acidosis enhanced phosphorylation of p38 in a sustained and very strong manner. ERK1/2 and JNK1/2 were not affected in fibroblasts. Inhibition of JNK1/2 and p38 under coculture conditions reduced acidosis-induced changes in fibroblasts significantly. CONCLUSIONS: Our data show that the crosstalk between proximal tubule cells and fibroblasts is crucial for acidosis-induced dedifferentiation of fibroblasts into an inflammatory phenotype. This dedifferentiation is at least in part mediated by p38 and JNK1/2. Thus, cell-cell communication is essential for the pathophysiological impact of tubulointerstitial acidosis.