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Background: Spread through air spaces (STAS) is one of the multiple modes of lung cancer dissemination, yet its molecular and clinicopathological characterization remains poorly studied. This study aimed to investigate the effect of adhesion molecule expression levels on the incidence of STAS and postoperative recurrence in stage I lung cancer patients undergoing radical resection. Methods: E-cadherin, P-cadherin, N-cadherin, focal adhesion kinase (FAK), epithelial cell adhesion molecule (EpCAM), neural cell adhesion molecule 1 (NCAM1), vascular cell adhesion molecule 1 (VCAM1), intercellular cell adhesion molecule-1 (ICAM-1) were analyzed retrospectively using immunohistochemistry in patients undergoing radical resection for stage I non-small cell lung cancer (NSCLC). Patients were categorized into four groups based on adhesion molecule expression levels: "low/low", "high/low", "low/high", and "high/high", and the group with the lowest recurrence-free probability (RFP) was defined as high risk. Associations between those adhesion molecules' expression levels and STAS were determined by using the Chi-squared test and logistic regression model. RFP was analyzed by using the log-rank test and Cox proportional risk model. Results: As of January 1, 2024, 12 of 60 patients undergoing radical resection for stage I lung carcinoma had a disease recurrence. All 60 patients' tissue specimens were retrospectively analyzed, and there were no significant differences between patients with STAS-positive (n=30) and STAS-negative (n=30) in baseline clinicopathologic features, except for histological growth patterns. We found that low expression of E-cadherin, high expression of N-cadherin and FAK, and males were independent predictors of higher incidence of STAS. Multivariate Cox analysis showed that tumors with low E-cadherin/high N-cadherin, low E-cadherin/high FAK, and high N-cadherin/high FAK expression were important predictors of recurrence in patients with stage I lung carcinoma. In addition, females and high N-cadherin/high FAK were associated with a high risk of recurrence in patients with STAS. Conclusions: E-cadherin, N-cadherin, and FAK are predictors of STAS occurrence in stage I NSCLC, and their combinations are prognostic factors. The discovery of these molecular markers provides clinicians with a reliable means that may help in the early identification of individuals with a higher risk of recurrence in lung cancer patients, targeting personalized treatment plans such as aggressive adjuvant therapy or closer follow-up.
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Drug resistance in melanoma is a major hindrance in cancer therapy. Growth hormone (GH) plays a pivotal role in contributing to the resistance to chemotherapy. Knocking down or blocking the GH receptor has been shown to sensitize the tumor cells to chemotherapy. Extensive studies have demonstrated that exosomes, a subset of extracellular vesicles, play an important role in drug resistance by transferring key factors to sensitize cancer cells to chemotherapy. In this study, we explore how GH modulates exosomal cargoes from melanoma cells and their role in drug resistance. We treated the melanoma cells with GH, doxorubicin, and the GHR antagonist, pegvisomant, and analyzed the exosomes released. Additionally, we administered these exosomes to the recipient cells. The GH-treated melanoma cells released exosomes with elevated levels of ABC transporters (ABCC1 and ABCB1), N-cadherin, and MMP2, enhancing drug resistance and migration in the recipient cells. GHR antagonism reduced these exosomal levels, restoring drug sensitivity and attenuating migration. Overall, our findings highlight a novel role of GH in modulating exosomal cargoes that drive chemoresistance and metastasis in melanoma. This understanding provides insights into the mechanisms of GH in melanoma chemoresistance and suggests GHR antagonism as a potential therapy to overcome chemoresistance in melanoma treatment.
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Most nervous systems combine both transmitter-mediated and direct cell-cell communication, known as 'chemical' and 'electrical' synapses, respectively. Chemical synapses can be identified by their multiple structural components. Electrical synapses are, on the other hand, generally defined by the presence of a 'gap junction' (a cluster of intercellular channels) between two neuronal processes. However, while gap junctions provide the communicating mechanism, it is unknown whether electrical transmission requires the contribution of additional cellular structures. We investigated this question at identifiable single synaptic contacts on the zebrafish Mauthner cells, at which gap junctions coexist with specializations for neurotransmitter release and where the contact unequivocally defines the anatomical limits of a synapse. Expansion microscopy of these single contacts revealed a detailed map of the incidence and spatial distribution of proteins pertaining to various synaptic structures. Multiple gap junctions of variable size were identified by the presence of their molecular components. Remarkably, most of the synaptic contact's surface was occupied by interleaving gap junctions and components of adherens junctions, suggesting a close functional association between these two structures. In contrast, glutamate receptors were confined to small peripheral portions of the contact, indicating that most of the synaptic area functions as an electrical synapse. Thus, our results revealed the overarching organization of an electrical synapse that operates with not one, but multiple gap junctions, in close association with structural and signaling molecules known to be components of adherens junctions. The relationship between these intercellular structures will aid in establishing the boundaries of electrical synapses found throughout animal connectomes and provide insight into the structural organization and functional diversity of electrical synapses.
Neurons communicate with each other through specialized structures known as synapses. At chemical synapses, the cells do not physically interact as they rely instead on molecules called neurotransmitters to pass along signals. At electrical synapses, however, neurons are directly connected via gap junctions, which are clusters of intercellular channels that allow ions and other small compounds to move from one cell to another. Both electrical and chemical synapses play critical roles in neural circuits, and both exhibit some amount of plasticity they weaken or strengthen depending on how often they are used, an important feature for the brain to adapt to the needs of the environment. Yet the structure and molecular organization of electrical synapses have remained poorly understood compared to their chemical counterparts. In response, Cárdenas-García, Ijaz and Pereda took advantage of a new approach known as expansion microscopy to examine the electrical synapse that connects neurons bringing sound information to a pair of unusually large neurons in the brain of most bony fish. With this method, a biological sample is prepared in such a way that its size increases, but the relative position of its components is preserved. This allows scientists to better observe structures that would otherwise be too difficult to capture using traditional microscopy techniques. Experiments in larval zebrafish revealed that contrary to previous assumptions, the electrical synapse was formed of not one but multiple gap junctions of various sizes closely associated with a range of structural and signaling molecules typically found in adherens junctions (a type of structure that physically links cells together). The team suggests that these molecular actors could work to ensure that the multiple gap junctions act in concert at the synapse. Overall, these findings offer a new perspective on how electrical synapses are organized and regulated, which refines our understanding of how the nervous system functions both in health and in disease.
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Sinapsis Eléctricas , Uniones Comunicantes , Pez Cebra , Animales , Sinapsis Eléctricas/fisiología , Uniones Comunicantes/metabolismo , Microscopía/métodos , Comunicación Celular , Transmisión Sináptica/fisiologíaRESUMEN
Cadherins are cell-cell adhesion proteins which have been strongly implicated in cancer invasion, dissemination and metastasis capacity; thus, they are key players in the epithelial-to-mesenchymal transition (EMT) program. However, their role in glioblastoma (GBM), a primary central nervous system aggressive tumor, remains to be clarified. N-, E- and P-cadherin expression was analyzed on a large series of GBMs, characterized with clinical, imaging and neuropathological parameters, as well as with patients' survival data. In addition, cadherins' expression was studied in match-recurrent cases. Using TCGA data, cadherin expression profiles were also evaluated according to GBM transcription subtypes. N-cadherin expression was observed in 81.5% of GBM, followed by E-cadherin in 31% and P-cadherin in 20.8%. Upon tumor recurrence, P-cadherin was the only significantly upregulated cadherin compared with the primary tumor, being positive in 65.8% of the cases. Actually, P-cadherin gain was observed in 51.4% of matched primary-recurrent cases. Cadherins' co-expression was also explored. Interestingly, E- and N-cadherin co-expression identified a GBM subgroup with frequent epithelial differentiation and a significant survival benefit. On the other hand, subgroups with P-cadherin expression carried the worse prognosis. P- and N-cadherin co-expression correlated with the presence of a mesenchymal phenotype. Expressions of isolated P-cadherin or E- and P-cadherin co-expression were associated with imaging characteristics of aggressiveness, to highly heterogeneous tumors, an d to worse patient survival. Classical cadherins co-expression subgroups present consistent clinical, imaging, neuropathological and survival differences, which probably reflect different states of an EMT-like program in GBM.
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Renal epithelial-to-mesenchymal transition (EMT) is a process in which epithelial cells undergo biochemical changes and transform into mesenchymal-like cells, resulting in renal abnormalities, including fibrosis. EMT can cause diabetic nephropathy through triggering kidney fibrosis, inflammation, and functional impairment. The diverse molecular pathways that drive EMT-mediated renal fibrosis are not utterly known. Targeting key signaling pathways involved in EMT may help ameliorate diabetic nephropathy and improve renal function. In such settings, understanding precisely the complicated signaling networks is critical for developing customized therapies to intervene in EMT-mediated diabetic nephropathy.
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The use of endosseous dental implants may become unfeasible in the presence of significant maxillary bone atrophy; thus, surgical techniques have been proposed to promote bone regeneration in such cases. However, such techniques are complex and may expose the patient to complications. Subperiosteal implants, being placed between the periosteum and the residual alveolar bone, are largely independent of bone thickness. Such devices had been abandoned due to the complexity of positioning and adaptation to the recipient bone site, but are nowadays witnessing an era of revival following the introduction of new acquisition procedures, new materials, and innovative manufacturing methods. We have analyzed the changes induced in gene and protein expression in C-12720 human osteoblasts by differently surface-modified TiO2 materials to verify their ability to promote bone formation. The TiO2 materials tested were (i) raw machined, (ii) electropolished with acid mixture, (iii) sand-blasted + acid-etched, (iv) AlTiColorTM surface, and (v) anodized. All five surfaces efficiently stimulated the expression of markers of osteoblastic differentiation, adhesion, and osteogenesis, such as RUNX2, osteocalcin, osterix, N-cadherin, ß-catenin, and osteoprotegerin, while cell viability/proliferation was unaffected. Collectively, our observations document that presently available TiO2 materials are well suited for the manufacturing of modern subperiosteal implants.
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Epithelial-mesenchymal transition (EMT) plays a pivotal role in the development and progression of many cancers. Partial EMT (pEMT) could represent a critical step in tumor migration and dissemination. Sarcomatoid renal cell carcinoma (sRCC) is an aggressive form of renal cell carcinoma (RCC) composed of a carcinomatous (sRCC-Ca) and sarcomatous (sRCC-Sa) component. The role of (p)EMT in the progression of RCC to sRCC remains unclear. The aim of this study was to investigate the involvement of (p)EMT in RCC and sRCC. Tissue samples from 10 patients with clear cell RCC (ccRCC) and 10 patients with sRCC were selected. The expression of main EMT markers (miR-200 family, miR-205, SNAI1/2, TWIST1/2, ZEB1/2, CDH1/2, VIM) was analyzed by qPCR in ccRCC, sRCC-Ca, and sRCC-Sa and compared to non-neoplastic tissue and between both groups. Expression of E-cadherin, N-cadherin, vimentin and ZEB2 was analyzed using immunohistochemistry. miR-200c was downregulated in sRCC-Ca compared to ccRCC, while miR-200a was downregulated in sRCC-Sa compared to ccRCC. CDH1 was downregulated in sRCC-Sa when compared to any other group. ZEB2 was downregulated in ccRCC and sRCC compared to corresponding non-neoplastic kidney. A positive correlation was observed between CDH1 expression and miR-200a/b/c. Our results suggest that full EMT is not present in sRCC. Instead, discreet molecular differences exist between ccRCC, sRCC-Ca, and sRCC-Sa, possibly representing distinct intermediary states undergoing pEMT.
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Biomarcadores de Tumor , Carcinoma de Células Renales , Transición Epitelial-Mesenquimal , Neoplasias Renales , MicroARNs , Vimentina , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc , Humanos , Transición Epitelial-Mesenquimal/genética , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Neoplasias Renales/patología , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , MicroARNs/genética , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Femenino , Vimentina/metabolismo , Vimentina/genética , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/genética , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/metabolismo , Anciano , Cadherinas/genética , Cadherinas/metabolismo , Regulación Neoplásica de la Expresión Génica , Antígenos CD/genética , Antígenos CD/metabolismo , Proteína 1 Relacionada con Twist/genética , Proteína 1 Relacionada con Twist/metabolismo , Factores de Transcripción de la Familia Snail/genética , Factores de Transcripción de la Familia Snail/metabolismo , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Transformación Celular Neoplásica/metabolismo , Adulto , Proteínas NuclearesRESUMEN
During epithelial to mesenchymal transition, the ability of cancer cells to transform and metastasize is primarily determined by N-cadherin-mediated migration and invasion. This study aimed to evaluate whether the N-cadherin promoter can induce diphtheria toxin expression as a suicide gene in epithelial to mesenchymal transition (EMT)-induced cancer cells and whether this can be used as potential gene therapy. To investigate the expression of diphtheria toxin under the N-cadherin promoter, the promoter was synthesized, and was cloned upstream of diphtheria toxin in a pGL3-Basic vector. The A-549 cells was transfected by electroporation. After induction of EMT by TGF-ß and hypoxia treatment, the relative expression of diphtheria toxin, mesenchymal genes such as N-cadherin and Vimentin, and epithelial genes such as E-cadherin and ß-catenin were measured by real-time PCR. MTT assay was also performed to measure cytotoxicity. Finally, cell motility was assessed by the Scratch test. After induction of EMT in transfected cells, the expression of mesenchymal markers such as Vimentin and N-cadherin significantly decreased, and the expression of ß-catenin increased. In addition, the MTT assay showed promising toxicity results after induction of EMT with TGF-ß in transfected cells, but toxicity was less effective in hypoxia. The scratch test results also showed that cell movement was successfully prevented in EMT-transfected cells and thus confirmed EMT occlusion. Our findings indicate that by using structures containing diphtheria toxin downstream of a specific EMT promoter such as the N-cadherin promoter, the introduced toxin can kill specifically and block EMT in cancer cells.
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Cadherinas , Toxina Diftérica , Transición Epitelial-Mesenquimal , Regiones Promotoras Genéticas , Humanos , Células A549 , Antígenos CD/genética , Antígenos CD/metabolismo , beta Catenina/metabolismo , beta Catenina/genética , Cadherinas/genética , Cadherinas/metabolismo , Movimiento Celular/genética , Movimiento Celular/efectos de los fármacos , Toxina Diftérica/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Genes Transgénicos Suicidas , Regiones Promotoras Genéticas/genética , Vimentina/genética , Vimentina/metabolismoRESUMEN
BACKGROUND: Bladder cancer metastasis is an essential process in the progression of muscle-invasive bladder cancer. EMT plays a crucial role in facilitating the spread of cancer cells. Identifying compounds that can inhibit these abilities of cancer cells is a significant international endeavor. OBJECTIVE: To explore the migration and invasion effect of Moscatilin on the bladder and clarify the mechanism of action Methods: The anti-bladder cancer effect of Moscatilin was observed by a cell proliferation experiment. The migration and invasion of bladder cancer cells inhibited by Moscatilin were detected by Transwell and Wound healing. The effects of Moscatilin on EMT-related proteins E-cadherin, N-cadherin, Snail1, Vimentin, and TGF-ß signaling pathways were detected by Western blot, and nucleic acid levels were verified by qPCR. RESULTS: Our study revealed that Moscatilin reduced the viability of bladder cancer cells in vitro and impeded their migration and invasion in experimental settings. Furthermore, we observed that Moscatilin decreased the activation levels of active proteins, specifically Smad3, Samd2, and MMP2. Additionally, we found that moscatilin significantly reduced the expression level of TGF-ß and was also capable of reversing the overexpression effect of TGF-ß. Treatment with Moscatilin also led to significant inhibition of interstitial cell markers Ncadherin and Snail1, which are associated with EMT. CONCLUSION: These findings indicate that Moscatilin impedes the migration and invasion of bladder cancer cells by influencing cell survival, modulating TGF-ß/Smad signaling, and inhibiting EMT.
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Movimiento Celular , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Transición Epitelial-Mesenquimal , Transducción de Señal , Factor de Crecimiento Transformador beta , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Relación Dosis-Respuesta a Droga , Células Tumorales Cultivadas , Estructura Molecular , Relación Estructura-Actividad , Supervivencia Celular/efectos de los fármacos , Pirazoles/farmacología , Pirazoles/química , QuinolinasRESUMEN
Epithelial-mesenchymal transition (EMT) promotes tumor cell infiltration and metastasis. Tracking the progression of EMT could potentially indicate early cancer metastasis. A key characteristic of EMT is the dynamic alteration in the molecular levels of E-cadherin and N-cadherin. Traditional assays have limited sensitivity and multiplexing capabilities, relying heavily on cell lysis. Here, we developed a multiplex electrochemical biosensor to concurrently track the upregulation of N-cadherin expression and reduction of E-cadherin in breast cancer cells undergoing EMT. Small-sized gold nanoparticles (Au NPs) tagged with redox probes (thionin or amino ferrocene) and bound to two types of antibodies were used as distinguishable signal tags. These tags specifically recognized E-cadherin and N-cadherin proteins on the tumor cell surface without cross-reactivity. The diphenylalanine dipeptide (FF)/chitosan (CS)/Au NPs (FF-CS@Au) composites with high surface area and good biocompatibility were used as the sensing platforms for efficiently fixing cells and recording the dynamic changes in electrochemical signals of surface proteins. The electrochemical immunosensor allowed for simultaneous monitoring of E- and N-cadherins on breast cancer cell surfaces in a single run, enabling tracking of the EMT dynamic process for up to 60 h. Furthermore, the electrochemical detection results are consistent with Western blot analysis, confirming the reliability of the methodology. This present work provides an effective, rapid, and low-cost approach for tracking the EMT process, as well as valuable insights into early tumor metastasis.
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Técnicas Biosensibles , Neoplasias de la Mama , Técnicas Electroquímicas , Transición Epitelial-Mesenquimal , Oro , Nanopartículas del Metal , Humanos , Técnicas Biosensibles/métodos , Neoplasias de la Mama/patología , Oro/química , Femenino , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Cadherinas , Línea Celular Tumoral , Inmunoensayo/métodos , Quitosano/químicaRESUMEN
BACKGROUND: DIREN is a SHE ethnic medicine with stasis-resolving, hemostasis, clearing heat, and removing toxin effects. It is clinically used in the treatment of gastrointestinal bleeding, such as ulcerative colitis (UC). AIM OF THE STUDY: Fibrosis is one of the pathological changes in the progression of UC, which can make it challenging to respond to a treatment. We aimed to illuminate the role of DIREN in DSS-induced UC and tried to unveil its related mechanisms from two perspectives: intestinal inflammation and collagen deposition. MATERIALS AND METHODS: A 2.5â¯% dextran sulfate sodium (DSS) water solution was used to induce colitis in mice. The therapeutic effect of DIREN was assessed using the disease activity index, histopathological score, and colon length. Masson and Sirius Red staining was used to observe the fibrosis in the colon. Apoptosis of colonic epithelial cells was observed by TUNEL immunofluorescence staining. RNA-seq observed differential genes and enrichment pathways. Immunohistochemistry and RT-qPCR were used to detect the expression of molecules related to fibrosis and focal adhesion signaling in colon tissue. RESULTS: The administration of DIREN resulted in a reduction of disease activity index (DAI) in mice with UC while simultaneously promoting an increase in colon length. DIREN mitigated the loss of goblet cells in the colon of UC mice and maintained the integrity of the intestinal mucosa barrier. Masson staining revealed a reduction in colonic fibrosis with DIREN treatment, while Sirius red staining demonstrated a decrease in collagen â deposition. DIREN reduced apoptosis of colonic epithelial cells and the expression of genes, such as CDH2, ITGA1, and TGF-ß2. Additionally, the results of GSEA analysis of colon tissue transcriptome showed that the differentially expressed genes were enriched in the focal adhesion pathway. DIREN was found to downregulate the protein expression of BAX, N-cadherin, ß-catenin, Integrin A1, and Vinculin while upregulating the protein expression of BCL2. Additionally, it led to the co-expression of N-cadherin and α-SMA. CONCLUSION: DIREN exerts a protective effect against DSS-induced UC by ameliorating colonic fibrosis via regulation of focal adhesion and the WNT/ß-catenin signaling pathway, thereby inhibiting fibroblast migration and reducing collagen secretion.
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Colágeno , Colon , Sulfato de Dextran , Adhesiones Focales , Vía de Señalización Wnt , Animales , Ratones , Vía de Señalización Wnt/efectos de los fármacos , Colágeno/metabolismo , Adhesiones Focales/efectos de los fármacos , Adhesiones Focales/metabolismo , Colon/efectos de los fármacos , Colon/patología , Colon/metabolismo , Ratones Endogámicos C57BL , Masculino , Colitis/inducido químicamente , Colitis/patología , Colitis/metabolismo , Colitis/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Fibrosis , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Colitis Ulcerosa/tratamiento farmacológico , Modelos Animales de Enfermedad , beta Catenina/metabolismoRESUMEN
Vitamin A deficiency (VAD) induced TGF-ß hyperactivation and reduced expression of cell adhesion proteins in the lung, suggesting that the disruption of retinoic acid (RA) signaling leads to epithelial-mesenchymal transition (EMT). To elucidate the role of lung vitamin A status in EMT, several EMT markers and the expression of the proprotein convertase furin, which activates TGF-ß, were analyzed in two experimental models. Our in vivo model included control rats, VAD rats, and both control rats and VAD rats, treated with RA. For the in vitro studies, human bronchoalveolar epithelial cells treated with RA were used. Our data show that EMT and furin are induced in VAD rats. Furthermore, furin expression continues to increase much more markedly after treatment of VAD rats with RA. In control rats and cell lines, an acute RA treatment induced a significant increase in furin expression, concomitant with changes in EMT markers. A ChIP assay demonstrated that RA directly regulates furin transcription. These results emphasize the importance of maintaining vitamin A levels within the physiological range since both levels below and above this range can cause adverse effects that, paradoxically, could be similar. The role of furin in EMT is discussed.
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Transición Epitelial-Mesenquimal , Furina , Pulmón , Deficiencia de Vitamina A , Vitamina A , Furina/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Animales , Humanos , Pulmón/metabolismo , Pulmón/efectos de los fármacos , Vitamina A/farmacología , Vitamina A/metabolismo , Ratas , Deficiencia de Vitamina A/metabolismo , Masculino , Tretinoina/farmacología , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Línea Celular , Ratas WistarRESUMEN
Collective cell migration is fundamental for the development of organisms and in the adult for tissue regeneration and in pathological conditions such as cancer. Migration as a coherent group requires the maintenance of cell-cell interactions, while contact inhibition of locomotion (CIL), a local repulsive force, can propel the group forward. Here we show that the cell-cell interaction molecule, N-cadherin, regulates both adhesion and repulsion processes during Schwann cell (SC) collective migration, which is required for peripheral nerve regeneration. However, distinct from its role in cell-cell adhesion, the repulsion process is independent of N-cadherin trans-homodimerisation and the associated adherens junction complex. Rather, the extracellular domain of N-cadherin is required to present the repulsive Slit2/Slit3 signal at the cell surface. Inhibiting Slit2/Slit3 signalling inhibits CIL and subsequently collective SC migration, resulting in adherent, nonmigratory cell clusters. Moreover, analysis of ex vivo explants from mice following sciatic nerve injury showed that inhibition of Slit2 decreased SC collective migration and increased clustering of SCs within the nerve bridge. These findings provide insight into how opposing signals can mediate collective cell migration and how CIL pathways are promising targets for inhibiting pathological cell migration.
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Cadherinas , Movimiento Celular , Inhibición de Contacto , Péptidos y Proteínas de Señalización Intercelular , Proteínas de la Membrana , Regeneración Nerviosa , Proteínas del Tejido Nervioso , Células de Schwann , Células de Schwann/metabolismo , Células de Schwann/fisiología , Animales , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Ratones , Cadherinas/metabolismo , Cadherinas/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Regeneración Nerviosa/fisiología , Locomoción/fisiología , Adhesión Celular , Transducción de SeñalRESUMEN
Bladder cancer aggressiveness is correlated with abnormal N-cadherin transmembrane glycoprotein expression. This protein is cleaved by the metalloprotease ADAM10 and the γ-secretase complex releasing a pro-angiogenic N-terminal fragment (NTF) and a proliferation-activating soluble C-terminal fragment (CTF2). Tetraspanin 15 (Tspan15) is identified as an ADAM10-interacting protein to induce selective N-cadherin cleavage. We first demonstrated, in invasive T24 bladder cancer cells, that N-cadherin was cleaved by ADAM10 generating NTF in the extracellular environment and leaving a membrane-anchored CTF1 fragment and that Tspan15 is required for ADAM10 to induce the selective N-cadherin cleavage. Targeting N-cadherin function in cancer is relevant to preventing tumor progression and metastases. For antitumor molecules to inhibit N-cadherin function, they should be complete and not cleaved. We first showed that the GW501516, an agonist of the nuclear receptor PPARß/δ, decreased Tspan15 and prevented N-cadherin cleavage thus decreasing NTF. Interestingly, the drug did not modify ADAM10 expression, which was important because it could limit side effects since ADAM10 cleaves numerous substrates. By targeting Tspan15 to block ADAM10 activity on N-cadherin, GW501516 could prevent NTF pro-tumoral effects and be a promising molecule to treat bladder cancer. More interestingly, it could optimize the effects of the N-cadherin antagonists those such as ADH-1 that target the N-cadherin ectodomain.
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Proteína ADAM10 , Secretasas de la Proteína Precursora del Amiloide , Antígenos CD , Cadherinas , Dipéptidos , Ácidos Hidroxámicos , Proteínas de la Membrana , Tetraspaninas , Neoplasias de la Vejiga Urinaria , Humanos , Proteína ADAM10/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Cadherinas/metabolismo , Línea Celular Tumoral , Proteínas de la Membrana/metabolismo , Invasividad Neoplásica , Proteolisis/efectos de los fármacos , Tetraspaninas/metabolismo , Tetraspaninas/genética , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/genéticaRESUMEN
Objective: To investigate the synergistic regulation of the polarization of mesenchymal stem cells by integrin and N-cadherin-mediated mechanical adhesion and the underlying mechanobiological mechanisms. Methods: Bilayer polyethylene glyeol (PEG) hydrogels were formulated and modified with RGD and HAVDI peptides, respectively, to achieve mechanical adhesion to integrin and N-cadherin and to replicate the integrin-mediated mechanical interaction between cells and the extracellular matrix and the N-cadherin-mediated cell-cell mechanical interaction. The polar proteins, phosphatidylinositol 3-kinase (PI3K) and phosphorylated myosin light chain (pMLC), were characterized through immunofluorescence staining in individual cells with or without contact with HAVDI peptides under integrin-mediated adhesion, N-cadherin-mediated adhesion, and different intracellular forces. Their expression levels and polar distribution were analyzed using Image J. Results: Integrin-mediated adhesion induced significantly higher polar strengths of PI3K and pMLC in the contact group than in those in the no contact group, resulting in the concentration of the polar angle of PI3K to ß-catenin in the range of 135° to 180° and the concentration of the polar angle of pMLC to ß-catenin in the range of 0° to 45° in the contact group. Inhibition of integrin function led to inhibition of the polarity distribution of PI3K in the contact group, but did not change the polarity distribution of pMLC protein. The effect of N-cadherin on the polarity distributions of PI3K and pMLC was similar to that of integrin. However, inhibition of the mechanical adhesion of N-cadherin led to inhibition of the polarity intensity and polarity angle distribution of PI3K and pMLC proteins in the contact group. Furthermore, inhibition of the mechanical adhesion of N-cadherin caused weakened polarity intensity of integrin ß1, reducing the proportion of cells with polarity angles between integrin ß1 and ß-catenin concentrating in the range of 135° to 180°. Additionally, intracellular forces influenced the polar distribution of PI3K and pMLC proteins. Reducing intracellular forces weakened the polarity intensity of PI3K and pMLC proteins and their polarity distribution, while increasing intracellular forces enhanced the polarity intensity of PI3K and pMLC proteins and their polarity distribution. Conclusion: Integrin and N-cadherin co-regulate the polarity distribution of cell proteins and N-cadherin can play an important role in the polarity regulation of stem cells through local inhibition of integrin.
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Cadherinas , Adhesión Celular , Integrinas , Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Cadherinas/metabolismo , Integrinas/metabolismo , Polaridad Celular/fisiología , beta Catenina/metabolismo , Cadenas Ligeras de Miosina/metabolismo , Humanos , Oligopéptidos/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Hidrogeles/químicaRESUMEN
Lgl1 protein plays a critical role in neurodevelopment, including hippocampus, olfactory bulb, and Purkinje cell. However, the specific mechanism of LGL1 function in the midbrain remains elusive. In this study, we generated Lgl1 conditional knockout mice using Pax2-Cre, which is expressed in the midbrain, and examined the functions of Lgl1 in the midbrain. Histological analysis exhibited abnormal midbrain development characterized by enlarged ventricular aqueduct and thinning tectum cortex. Lgl1 deletion caused excessive proliferation and heightened apoptosis of neural progenitor cells in the tectum of LP cko mice. BrdU labeling studies demonstrated abnormal neuronal migration. Immunofluorescence analysis of Nestin demonstrated an irregular and clustered distribution of glial cell fibers, with the adhesion junction marker N-cadherin employed for immunofluorescent labeling, unveiling abnormal epithelial connections within the tectum of LP cko mice. The current findings suggest that the deletion of Lgl1 leads to the disruption of the expression pattern of N-cadherin, resulting in abnormal development of the midbrain.
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BACKGROUND: Epithelial-mesenchymal transition (EMT) enables tumor cell invasion and metastasis. Many studies have demonstrated the critical role of EMT in lymph node metastasis in oral squamous cell carcinoma (OSCC). During EMT, epithelial cancer cells lose intercellular adhesion and apical-basal polarity and acquire mesenchymal properties such as motility and invasiveness. A significant feature of EMT is cadherin switching, involving the downregulation of E-cadherin and upregulation of N-cadherin. The TGF-ß/SMAD pathway can also induce EMT. We aimed to evaluate EMT markers as predictors of lymph node metastasis in OSCC. METHODS: We performed genetic profiling of 159 primary OSCCs from TCGA and analyzed the expression of EMT markers, including cadherin switch genes (CDH1, CDH2), and TGF-ß/SMAD pathway genes. Samples were divided into advanced (stage III-IV) and early (stage I-II) stage groups. Differential expression analysis was performed, as well as an independent validation study containing fresh OSCC samples. RESULTS: TGF-ß/SMAD pathway genes such as SMAD6 were upregulated in advanced stage tumors. N-cadherin and SNAIL2 were overexpressed in node-positive tumors. Keratins were downregulated in these groups. CONCLUSION: Our findings demonstrate that EMT marker expression correlates with lymph node metastasis in OSCC. Developing therapies targeting regulators such as N-cadherin may prevent metastasis and improve outcomes.
RESUMEN
Endometrial cancer (EC) is the most common gynecological malignancy. This study aimed to evaluate the expression of E-cadherin and N-cadherin in primary endometrial lesions and the endocervix in patients with EC to identify noninvasive predictive factors. In this single-center retrospective study, data on 101 patients who underwent surgery for EC were collected. The immunohistochemical expression of E-cadherin and N-cadherin was assessed depending on the tumor grade, location, and cell differentiation. Correlations between E-cadherin and N-cadherin levels in the endocervix and the primary tumor were determined. The degree of histological tumor differentiation significantly affected E-cadherin expression (p = 0.04) but had no impact on N-cadherin levels. In type II EC, the expression of both cadherins in the tumor tissue differed from their endocervical levels. The expression of E-cadherin differed significantly between the endocervix (p < 0.001) and the tumor (p = 0.001), depending on the type of EC. The expression of E-cadherin was related to the N-cadherin level only in the endocervix in patients with type II EC (p = 0.02). E-cadherin and N-cadherin were expressed in the endocervix in patients with EC. The expression of cadherins, determined during cervical cytology, may be a valuable clinical marker of EC.