RÉSUMÉ
Colorectal cancer is a prevalent malignancy, with advanced and metastatic forms exhibiting poor treatment outcomes and high relapse rates. To enhance patient outcomes, a comprehensive understanding of the pathophysiological processes and the development of targeted therapies are imperative. The high heterogeneity of colorectal cancer demands precise and personalized treatment strategies. Colorectal cancer organoids, a three-dimensional in vitro model, have emerged as a valuable tool for replicating tumor biology and exhibit promise in scientific research, disease modeling, drug screening, and personalized medicine. In this review, we present an overview of colorectal cancer organoids and explore their applications in research and personalized medicine, while also discussing potential future developments in this field.
Sujet(s)
Tumeurs colorectales , Organoïdes , Médecine de précision , Humains , Organoïdes/anatomopathologie , Tumeurs colorectales/anatomopathologie , Tumeurs colorectales/thérapie , AnimauxRÉSUMÉ
Objective: This cross-sectional study aimed to explore the association of overweight and inflammatory indicators with breast cancer risk in Chinese patients. Methods: Weight, height, and peripheral blood inflammatory indicators, including white blood cell count (WBC), neutrophil count (NE), lymphocyte count (LY), platelet count (PLT) and the concentration of hypersensitivity C-reactive protein (hsCRP), were collected in 383 patients with benign breast lumps (non-cancer) and 358 patients with malignant breast tumors (cancer) at the First Affiliated Hospital of Soochow University, China, from March 2018 to July 2020. Body mass index (BMI), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and systemic immune-inflammation index (SII) were determined according to the ratio equation. The correlations among overweight, inflammatory indicators, and the proportion of non-cancer or cancer cases were analyzed. Results: BMI is associated with an increased breast cancer risk. Compared with non-cancer patients, the average WBC count, NE count, NLR, and level of hsCRP were significantly higher in cancer patients. The level of hsCRP was closely associated with the size of malignant breast tumors. Conclusion: We conclude that overweight and high levels of hsCRP may serve as putative risk factors for malignant breast tumors in Chinese women.
RÉSUMÉ
Dynamic regulation of intestinal epithelial cell (IEC) differentiation is crucial for both homeostasis and the response to helminth infection. SIRT6 belongs to the NAD+-dependent deacetylases and has established diverse roles in aging, metabolism and disease. Here, we report that IEC Sirt6 deletion leads to impaired tuft cell development and type 2 immunity in response to helminth infection, thereby resulting in compromised worm expulsion. Conversely, after helminth infection, IEC SIRT6 transgenic mice exhibit enhanced epithelial remodeling process and more efficient worm clearance. Mechanistically, Sirt6 ablation causes elevated Socs3 expression, and subsequently attenuated tyrosine 641 phosphorylation of STAT6 in IECs. Notably, intestinal epithelial overexpression of constitutively activated STAT6 (STAT6vt) in mice is sufficient to induce the expansion of tuft and goblet cell linage. Furthermore, epithelial STAT6vt overexpression remarkedly reverses the defects in intestinal epithelial remodeling caused by Sirt6 ablation. Our results reveal a novel function of SIRT6 in regulating intestinal epithelial remodeling and mucosal type 2 immunity in response to helminth infection.
Sujet(s)
Helminthiase/immunologie , Muqueuse intestinale , Facteur de transcription STAT-6/métabolisme , Sirtuines/métabolisme , Animaux , Cellules épithéliales/métabolisme , Cellules caliciformes/métabolisme , Helminthiase/métabolisme , Immunité muqueuse , Muqueuse intestinale/métabolisme , Intestins , Souris , Souris de lignée C57BL , Souris transgéniques , Facteur de transcription STAT-6/génétique , Sirtuines/génétiqueRÉSUMÉ
Erectile dysfunction (ED) is closely associated with smooth muscle dysfunction, but its underlying mechanisms remains incompletely understood. We here reported that the reduced expression of myosin phosphatase target subunit 1 (MYPT1), the main regulatory unit of myosin light chain phosphatase, was critical for the development of vasculogenic ED. Male MYPT1 knockout mice had reduced fertility and the penises displayed impaired erections as evidenced by reduced intracavernous pressure (ICP). The penile smooth muscles of the knockout mice displayed enhanced response to G-Protein Couple Receptor agonism and depolarization contractility and resistant relaxation. We further identified a natural compound lotusine that increased the MYPT1 expression by inhibiting SIAH1/2 E3 ligases-mediated protein degradation. This compound sufficiently restored the ICP and improved histological characters of the penile artery of Mypt1 haploinsufficiency mice. In diabetic ED mice (db/db), the decreased expression of MYPT1 was measured, and ICP was improved by lotusine treatment. We conclude that the reduction of MYPT1 is the major pathogenic factor of vasculogenic ED. The restoration of MYPT1 by lotusine improved the function of injured penile smooth muscles, and could be a novel strategy for ED therapy.
Sujet(s)
Dysfonctionnement érectile , Animaux , Dysfonctionnement érectile/traitement médicamenteux , Dysfonctionnement érectile/métabolisme , Mâle , Souris , Souris knockout , Muscles lisses/physiologie , Myosin-light-chain phosphatase/génétique , Myosin-light-chain phosphatase/métabolisme , Phosphorylation , Facteurs de virulence/métabolismeRÉSUMÉ
Inflammatory bowel disease (IBD) is a chronic relapsing-remitting inflammatory disease of the gastrointestinal tract. Patients are usually diagnosed in adolescence and early adulthood and need lifelong treatment. In recent years, it has been found that diet plays an important role in the pathogenesis of IBD. Diet can change intestinal barrier function, affect the structure and function of intestinal flora, and promote immune disorder, thus promoting inflammation. Many patients believe that diet plays a role in the onset and treatment of the disease and changes their diet spontaneously. This review provides some insights into how nutraceuticals regulate intestinal immune homeostasis and improve intestinal barrier function. We reviewed the research results of dietary fiber, polyphenols, bioactive peptides, and other nutraceuticals in the prevention and treatment of IBD and sought better alternative or supplementary treatment methods for IBD patients.
RÉSUMÉ
Genetic hearing loss is a common health problem with no effective therapy currently available. DFNA15, caused by mutations of the transcription factor POU4F3, is one of the most common forms of autosomal dominant non-syndromic deafness. In this study, we established a novel mouse model of the human DFNA15 deafness, with a Pou4f3 gene mutation (Pou4f3Δ) identical to that found in a familial case of DFNA15. The Pou4f3(Δ/+) mice suffered progressive deafness in a similar manner to the DFNA15 patients. Hair cells in the Pou4f3(Δ/+) cochlea displayed significant stereociliary and mitochondrial pathologies, with apparent loss of outer hair cells. Progression of hearing and outer hair cell loss of the Pou4f3(Δ/+) mice was significantly modified by other genetic and environmental factors. Using Pou4f3(-/+) heterozygous knockout mice, we also showed that DFNA15 is likely caused by haploinsufficiency of the Pou4f3 gene. Importantly, inhibition of retinoic acid signaling by the aldehyde dehydrogenase (Aldh) and retinoic acid receptor inhibitors promoted Pou4f3 expression in the cochlear tissue and suppressed the progression of hearing loss in the mutant mice. These data demonstrate Pou4f3 haploinsufficiency as the main underlying cause of human DFNA15 deafness and highlight the therapeutic potential of Aldh inhibitors for treatment of progressive hearing loss.
Sujet(s)
Aldehyde dehydrogenase/antagonistes et inhibiteurs , Antienzymes/pharmacologie , Cellules ciliées auditives/anatomopathologie , Perte d'audition/traitement médicamenteux , Perte d'audition/étiologie , Protéines à homéodomaine/génétique , Facteur de transcription Brn-3C/génétique , Animaux , Benzaldéhydes/pharmacologie , Modèles animaux de maladie humaine , Haploinsuffisance/génétique , Perte d'audition/génétique , Perte d'audition/anatomopathologie , Protéines à homéodomaine/métabolisme , Humains , Souris de lignée C57BL , Lignées consanguines de souris , Souris knockout , Bruit/effets indésirables , Quinoléines/pharmacologie , Facteur de transcription Brn-3C/métabolisme , Trétinoïne/pharmacologie , para-Aminobenzoates/pharmacologieRÉSUMÉ
Intestinal barrier function is required for the maintenance of mucosal homeostasis. Barrier dysfunction is thought to promote progression of both intestinal and systemic diseases. In many cases, this barrier loss reflects increased permeability of the paracellular tight junction as a consequence of myosin light chain kinase (MLCK) activation and myosin II regulatory light chain (MLC) phosphorylation. Although some details about MLCK activation remain to be defined, it is clear that this triggers perijunctional actomyosin ring (PAMR) contraction that leads to molecular reorganization of tight junction structure and composition, including occludin endocytosis. In disease states, this process can be triggered by pro-inflammatory cytokines including tumor necrosis factor-α (TNF), interleukin-1ß (IL-1ß), and several related molecules. Of these, TNF has been studied in the greatest detail and is known to activate long MLCK transcription, expression, enzymatic activity, and recruitment to the PAMR. Unfortunately, toxicities associated with inhibition of MLCK expression or enzymatic activity make these unsuitable as therapeutic targets. Recent work has, however, identified a small molecule that prevents MLCK1 recruitment to the PAMR without inhibiting enzymatic function. This small molecule, termed Divertin, restores barrier function after TNF-induced barrier loss and prevents disease progression in experimental chronic inflammatory bowel disease.
Sujet(s)
Perméabilité des membranes cellulaires , Cellules épithéliales/métabolisme , Homéostasie , Muqueuse intestinale/métabolisme , Myosin-Light-Chain Kinase/métabolisme , Animaux , Humains , Transduction du signalRÉSUMÉ
The intestinal epithelium acts as a barrier that prevents luminal contents, such as pathogenic microbiota and toxins, from entering the rest of the body. Epithelial barrier function requires the integrity of intestinal epithelial cells. While epithelial cell proliferation maintains a continuous layer of cells that forms a barrier, epithelial damage leads to barrier dysfunction. As a result, luminal contents can across the intestinal barrier via an unrestricted pathway. Dysfunction of intestinal barrier has been associated with many intestinal diseases, such as inflammatory bowel disease. Isolated mouse intestinal crypts can be cultured and maintained as crypt-villus-like structures, which are termed intestinal organoids or "enteroids". Enteroids are ideal to study the proliferation and cell death of intestinal epithelial cells in vitro. In this protocol, we describe a simple method to quantify the number of proliferative and dead cells in cultured enteroids. 5-ethynyl-2'-deoxyuridine (EdU) and propidium iodide are used to label proliferating and dead cells in enteroids, and the proportion of proliferating and dead cells are then analyzed by flow cytometry. This is a useful tool to test the effects of drug treatment on intestinal epithelial cell proliferation and cell survival.
Sujet(s)
Muqueuse intestinale/métabolisme , Animaux , Prolifération cellulaire , Cytométrie en flux , SourisRÉSUMÉ
Emotional information is critical for our social life, in which attentional bias is now a focus in the study on attention. However, the attentional bias processing mechanism of emotional faces still arouses huge controversy. Using similar experimental paradigms and stimuli, the published studies have yielded contradictory results. Some studies suggest that angry faces could automatically stimulate attention, that is, there is an anger superiority effect. On the contrary, lines of growing evidence support the existence of a happiness superiority effect, suggesting that the superiority effect is shown in happy faces rather than angry faces. In the present paper, the behavioral and neuroscience studies of anger and happiness superiority effects are combined. It is found that there are three major reasons for the debate over the two types of effects, which include the choice of stimulus materials, the difference of paradigm setting, and the different stages of emotional processing. By comparatively integrating the previous published results, we highlight that the future studies should further control the experimental materials and procedures, and investigate the processing mechanism of anger and happiness superiority effects by combining cognitive neurobiology means to resolve the disputes.
Sujet(s)
Colère , Biais attentionnel , Expression faciale , Bonheur , HumainsRÉSUMÉ
BACKGROUND & AIMS: Epithelial regeneration is essential for homeostasis and repair of the mucosal barrier. In the context of infectious and immune-mediated intestinal disease, interleukin (IL) 22 is thought to augment these processes. We sought to define the mechanisms by which IL22 promotes mucosal healing. METHODS: Intestinal stem cell cultures and mice were treated with recombinant IL22. Cell proliferation, death, and differentiation were assessed in vitro and in vivo by morphometric analysis, quantitative reverse transcriptase polymerase chain reaction, and immunohistochemistry. RESULTS: IL22 increased the size and number of proliferating cells within enteroids but decreased the total number of enteroids. Enteroid size increases required IL22-dependent up-regulation of the tight junction cation and water channel claudin-2, indicating that enteroid enlargement reflected paracellular flux-induced swelling. However, claudin-2 did not contribute to IL22-dependent enteroid loss, depletion of Lgr5+ stem cells, or increased epithelial proliferation. IL22 induced stem cell apoptosis but, conversely, enhanced proliferation within and expanded numbers of transit-amplifying cells. These changes were associated with reduced wnt and notch signaling, both in vitro and in vivo, as well as skewing of epithelial differentiation, with increases in Paneth cells and reduced numbers of enteroendocrine cells. CONCLUSIONS: IL22 promotes transit-amplifying cell proliferation but reduces Lgr5+ stem cell survival by inhibiting notch and wnt signaling. IL22 can therefore promote or inhibit mucosal repair, depending on whether effects on transit-amplifying or stem cells predominate. These data may explain why mucosal healing is difficult to achieve in some inflammatory bowel disease patients despite markedly elevated IL22 production.
Sujet(s)
Interleukines/pharmacologie , Récepteurs couplés aux protéines G/métabolisme , Récepteurs Notch/métabolisme , Cellules souches/cytologie , Cellules souches/métabolisme , Voie de signalisation Wnt/effets des médicaments et des substances chimiques , Animaux , Apoptose/effets des médicaments et des substances chimiques , Marqueurs biologiques/métabolisme , Numération cellulaire , Différenciation cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Claudine-2/métabolisme , Entérocytes/cytologie , Entérocytes/effets des médicaments et des substances chimiques , Entérocytes/métabolisme , Intestins/cytologie , Souris , Souris de lignée C57BL , Organoïdes/métabolisme , Cellules souches/effets des médicaments et des substances chimiques , Régulation positive/effets des médicaments et des substances chimiques ,RÉSUMÉ
The intestinal barrier defends against pathogenic microorganism and microbial toxin. Its function is regulated by tight junction permeability and epithelial cell integrity, and disruption of the intestinal barrier function contributes to progression of gastrointestinal and systemic disease. Two simple methods are described here to measure the permeability of intestinal epithelium. In vitro, Caco-2BBe cells are plated in tissue culture wells as a monolayer and transepithelial electrical resistance (TER) can be measured by an epithelial (volt/ohm) meter. This method is convincing because of its user-friendly operation and repeatability. In vivo, mice are gavaged with 4 kDa fluorescein isothiocyanate (FITC)-dextran, and the FITC-dextran concentrations are measured in collected serum samples from mice to determine the epithelial permeability. Oral gavage provides an accurate dose, and therefore is the preferred method to measure the intestinal permeability in vivo. Taken together, these two methods can measure the permeability of the intestinal epithelium in vitro and in vivo, and hence be used to study the connection between diseases and barrier function.
Sujet(s)
Cellules épithéliales/composition chimique , Muqueuse intestinale/composition chimique , Animaux , Humains , Muqueuse intestinale/anatomopathologie , Souris , PerméabilitéRÉSUMÉ
Diarrhea is a host response to enteric pathogens, but its impact on pathogenesis remains poorly defined. By infecting mice with the attaching and effacing bacteria Citrobacter rodentium, we defined the mechanisms and contributions of diarrhea and intestinal barrier loss to host defense. Increased permeability occurred within 2 days of infection and coincided with IL-22-dependent upregulation of the epithelial tight junction protein claudin-2. Permeability increases were limited to small molecules, as expected for the paracellular water and Na+ channel formed by claudin-2. Relative to wild-type, claudin-2-deficient mice experienced severe disease, including increased mucosal colonization by C. rodentium, prolonged pathogen shedding, exaggerated cytokine responses, and greater tissue injury. Conversely, transgenic claudin-2 overexpression reduced disease severity. Chemically induced osmotic diarrhea reduced colitis severity and C. rodentium burden in claudin-2-deficient, but not transgenic, mice, demonstrating that claudin-2-mediated protection is the result of enhanced water efflux. Thus, IL-22-induced claudin-2 upregulation drives diarrhea and pathogen clearance.
Sujet(s)
Claudine-2/métabolisme , Diarrhée/métabolisme , Infections à Enterobacteriaceae/immunologie , Épithélium/métabolisme , Interleukines/métabolisme , Muqueuse intestinale/métabolisme , Régulation positive , Animaux , Perméabilité des membranes cellulaires , Citrobacter rodentium/immunologie , Citrobacter rodentium/pathogénicité , Colite/microbiologie , Cytokines/métabolisme , Diarrhée/immunologie , Diarrhée/microbiologie , Diarrhée/anatomopathologie , Modèles animaux de maladie humaine , Infections à Enterobacteriaceae/microbiologie , Épithélium/immunologie , Épithélium/microbiologie , Épithélium/anatomopathologie , Immunité innée/immunologie , Muqueuse intestinale/immunologie , Muqueuse intestinale/microbiologie , Intestins/microbiologie , Intestins/anatomopathologie , Souris , Souris de lignée C57BL , Sodium/métabolisme , Jonctions serrées/métabolisme , Eau/métabolisme ,RÉSUMÉ
Leiomyosarcoma is a rare malignant smooth muscle tumor which can be very unpredictable. Myosin II is involved in many functions, including cell contraction, migration, and adhesion. The phosphorylation of myosin regulatory light chain (MLC) by myosin light chain kinase (MLCK) determines the activity of Myosin II. However, it is still unclear whether MLC phosphorylation is involved in cell proliferation in leiomyosarcoma. In this study, we aimed to explore the role of MLCK-dependent MLC phosphorylation in leiomyosarcoma development. We found that the expression of MLCK, phosphorylated MLC, and Ki67 in leiomyosarcoma was significantly higher than in leiomyoma and adjacent normal smooth muscle cells. MLCK expression was significantly correlated with phosphorylated MLC level. Kaplan-Meier survival analysis revealed that patients with high expression of MLCK or phosphorylated MLC had shorter overall survival times compared with the patients with low expression of MLCK or phosphorylated MLC. In vitro studies revealed a causative link between MLC phosphorylation and cellular proliferation as expression of phosphomimetic MLC (T19D, S20D) increased cellular proliferation as assessed by Ki67 staining. In contrast, MLCK specific inhibitor reduced cellular proliferation. We concluded that MLCK, phosphorylated MLC and Ki67 were overexpressed in leiomyosarcoma. MLCK dependent MLC phosphorylation might be responsible for the high proliferative state in leiomyosarcoma. MLCK and phosphorylated MLC are potential prognostic indicators of leiomyosarcoma.
Sujet(s)
Carcinogenèse/métabolisme , Carcinogenèse/anatomopathologie , Léiomyosarcome/métabolisme , Léiomyosarcome/anatomopathologie , Chaînes légères de myosine/métabolisme , Lignée cellulaire tumorale , Prolifération cellulaire , Femelle , Humains , Estimation de Kaplan-Meier , Antigène KI-67/métabolisme , Adulte d'âge moyen , Myocytes du muscle lisse/métabolisme , Myocytes du muscle lisse/anatomopathologie , Myosin-Light-Chain Kinase/métabolisme , Phosphorylation , PronosticRÉSUMÉ
BACKGROUND: Overexpression of cyclin D1 dependent kinases 4 and 6 (CDK4/6) is a common feature of many human cancers including leukemia. LEE011 is a novel inhibitor of both CDK4 and 6. To date, the molecular function of LEE011 in leukemia remains unclear. METHODS: Leukemia cell growth and apoptosis following LEE011 treatment was assessed through CCK-8 and annexin V/propidium iodide staining assays. Cell senescence was assessed by ß-galactosidase staining and p16INK4a expression analysis. Gene expression profiles of LEE011 treated HL-60 cells were investigated using an Arraystar Human LncRNA array. Gene ontology and KEGG pathway analysis were then used to analyze the differentially expressed genes from the cluster analysis. RESULTS: Our studies demonstrated that LEE011 inhibited proliferation of leukemia cells and could induce apoptosis. Hoechst 33,342 staining analysis showed DNA fragmentation and distortion of nuclear structures following LEE011 treatment. Cell cycle analysis showed LEE011 significantly induced cell cycle G1 arrest in seven of eight acute leukemia cells lines, the exception being THP-1 cells. ß-Galactosidase staining analysis and p16INK4a expression analysis showed that LEE011 treatment can induce cell senescence of leukemia cells. LncRNA microarray analysis showed 2083 differentially expressed mRNAs and 3224 differentially expressed lncRNAs in LEE011-treated HL-60 cells compared with controls. Molecular function analysis showed that LEE011 induced senescence in leukemia cells partially through downregulation of the transcriptional expression of MYBL2. CONCLUSIONS: We demonstrate for the first time that LEE011 treatment results in inhibition of cell proliferation and induction of G1 arrest and cellular senescence in leukemia cells. LncRNA microarray analysis showed differentially expressed mRNAs and lncRNAs in LEE011-treated HL-60 cells and we demonstrated that LEE011 induces cellular senescence partially through downregulation of the expression of MYBL2. These results may open new lines of investigation regarding the molecular mechanism of LEE011 induced cellular senescence.
RÉSUMÉ
Decreased autophagy is accompanied by the development of a myeloproliferative state or acute myeloid leukemia (AML). AML cells are often sensitive to autophagyinducing stimuli, prompting the idea that targeting autophagy can be useful in AML cytotoxic therapy. AML NB4 cells overexpressing microtubule-associated protein 1 light chain 3-green fluorescent protein were screened with 69 inhibitors to analyze autophagy activity. AML cells were treated with the polo-like kinase 1 (PLK1) inhibitors RO3280 and BI2536 before autophagy analysis. Cleaved LC3 (LC3-II) and the phosphorylation of mammalian target of rapamycin (mTOR), adenosine monophosphate-activated protein kinase, and Unc-51-like kinase 1 during autophagy was detected with western blotting. Autophagosomes were detected using transmission electron microscopy. Several inhibitors had promising autophagy inducer effects: BI2536, MLN0905, SK1-I, SBE13 HCL and RO3280. Moreover, these inhibitors all targeted PLK1. Autophagy activity was increased in the NB4 cells treated with RO3280 and BI2536. Inhibition of PLK1 expression in NB4, K562 and HL-60 leukemia cells with RNA interference increased LC3-II and autophagy activity. The phosphorylation of mTOR was reduced significantly in NB4 cells treated with RO3280 and BI2536, and was also reduced significantly when PLK1 expression was downregulated in the NB4, K562 and HL-60 cells. We demonstrate that PLK1 inhibition induces AML cell autophagy and that it results in mTOR dephosphorylation. These results may provide new insights into the molecular mechanism of PLK1 in regulating autophagy.
Sujet(s)
Autophagie , Marqueurs biologiques tumoraux/métabolisme , Protéines du cycle cellulaire/métabolisme , Leucémie aigüe myéloïde/anatomopathologie , Protein-Serine-Threonine Kinases/métabolisme , Protéines proto-oncogènes/métabolisme , Sérine-thréonine kinases TOR/métabolisme , Animaux , Marqueurs biologiques tumoraux/génétique , Technique de Western , Protéines du cycle cellulaire/antagonistes et inhibiteurs , Protéines du cycle cellulaire/génétique , Prolifération cellulaire , Enfant , Femelle , Humains , Leucémie aigüe myéloïde/génétique , Leucémie aigüe myéloïde/métabolisme , Mâle , Souris , Stadification tumorale , Phosphorylation , Pronostic , Protein-Serine-Threonine Kinases/antagonistes et inhibiteurs , Protein-Serine-Threonine Kinases/génétique , Protéines proto-oncogènes/antagonistes et inhibiteurs , Protéines proto-oncogènes/génétique , ARN messager/génétique , Petit ARN interférent/génétique , Réaction de polymérisation en chaine en temps réel , RT-PCR , Transduction du signal , Taux de survie , Sérine-thréonine kinases TOR/génétique , Cellules cancéreuses en culture , Tests d'activité antitumorale sur modèle de xénogreffe ,RÉSUMÉ
Sphingosine kinase 1 (SphK1) is over-expressed in many cancers and therefore serves as a biomarker for cancer prognosis. SKI-5C is a new SphK1 inhibitor, and until now its molecular function in Wilms' tumor cells remained unknown. Here, using CCK-8 and nude mice experiments we assessed cell growth in Wilms' tumor cell lines (SK-NEP-1 and G401) in vitro and in vivo. We demonstrated that SphK1 is highly expressed in SK-NEP-1 and G401 cells, and through annexin V/propidium iodide staining and flow cytometry analysis, we detected cell apoptosis. Treatment with SKI-5C inhibited proliferation and induced apoptosis of SK-NEP-1 and G401 cells in a dose-dependent manner. Moreover, SKI-5C treatment inhibited the growth of SK-NEP-1 xenograft tumors in nude mice, with few side effects. Our microarray analysis revealed that SKI-5C-treated SK-NEP-1 cells mostly downregulated PRKACA and significantly inhibited phosphorylation of ERK1/2 and NF-κB p65. These results imply that SKI-5C induces apoptosis of SK-NEP-1 cells through the PRKACA/MAPK/NF-κB pathway. While, further research is required to determine the underlying details, these results provide new clues for the molecular mechanism of cell death induced by SKI-5C and suggest that SKI-5C may act as new candidate drug for Wilms' tumor.
RÉSUMÉ
The regulation of intestinal epithelial permeability requires phosphorylation of myosin regulatory light chain (MLC). The phosphorylation status of MLC is regulated by myosin light chain phosphatase (MLCP) activities. The activity of the catalytic subunit of MLCP (PP1cδ) toward MLC depends on its regulatory subunit (MYPT1). In this study, we revealed the presence of two MYPT1 isoforms, full length and variant 2 in human intestinal (Caco-2) epithelial cells and isolated intestinal epithelial cells (IECs) from mice. In confluent Caco-2 cells, MYPT1 was distributed at cell-cell contacts and colocalized with F-actin. These results suggest that MYPT1 isoforms are expressed in intestinal epithelial cells and MYPT1 may be involved in the regulation of intestinal epithelial barrier function.
Sujet(s)
Épissage alternatif , Myosin-light-chain phosphatase/génétique , Actines/métabolisme , Animaux , Cellules Caco-2 , Lignée cellulaire tumorale , Cellules cultivées , Cellules épithéliales/métabolisme , Humains , Souris , Souris de lignée C57BL , Spécificité d'organe , Isoformes de protéines/génétiqueRÉSUMÉ
Smooth muscle sphincters exhibit basal tone and control passage of contents through organs such as the gastrointestinal tract; loss of this tone leads to disorders such as faecal incontinence. However, the molecular mechanisms underlying this tone remain unknown. Here, we show that deletion of myosin light-chain kinases (MLCK) in the smooth muscle cells from internal anal sphincter (IAS-SMCs) abolishes basal tone, impairing defecation. Pharmacological regulation of ryanodine receptors (RyRs), L-type voltage-dependent Ca(2+) channels (VDCCs) or TMEM16A Ca(2+)-activated Cl(-) channels significantly changes global cytosolic Ca(2+) concentration ([Ca(2+)]i) and the tone. TMEM16A deletion in IAS-SMCs abolishes the effects of modulators for TMEM16A or VDCCs on a RyR-mediated rise in global [Ca(2+)]i and impairs the tone and defecation. Hence, MLCK activation in IAS-SMCs caused by a global rise in [Ca(2+)]i via a RyR-TMEM16A-VDCC signalling module sets the basal tone. Targeting this module may lead to new treatments for diseases like faecal incontinence.
Sujet(s)
Canal anal/métabolisme , Canaux calciques de type L/métabolisme , Canaux chlorure/métabolisme , Incontinence anale/métabolisme , Hypotonie musculaire/métabolisme , Myosin-Light-Chain Kinase/génétique , Canal de libération du calcium du récepteur à la ryanodine/métabolisme , Canal anal/effets des médicaments et des substances chimiques , Canal anal/physiopathologie , Animaux , Anoctamine-1 , Béthanéchol/pharmacologie , Calcium/métabolisme , Canaux calciques de type L/génétique , Signalisation calcique , Canaux chlorure/génétique , Défécation/effets des médicaments et des substances chimiques , Incontinence anale/génétique , Incontinence anale/physiopathologie , Femelle , Régulation de l'expression des gènes , Humains , Mâle , Potentiels de membrane/effets des médicaments et des substances chimiques , Potentiels de membrane/physiologie , Souris , Souris de lignée C57BL , Souris transgéniques , Contraction musculaire/effets des médicaments et des substances chimiques , Hypotonie musculaire/génétique , Hypotonie musculaire/physiopathologie , Muscles lisses/effets des médicaments et des substances chimiques , Muscles lisses/métabolisme , Muscles lisses/physiopathologie , Myosin-Light-Chain Kinase/déficit , Nifédipine/pharmacologie , Acide niflumique/pharmacologie , Techniques de patch-clamp , Canal de libération du calcium du récepteur à la ryanodine/génétiqueRÉSUMÉ
Stroke, either ischemic or hemorrhagic, is the leading cause of death and morbidity worldwide. Identifying the risk factors is a prerequisite step for stroke prevention and treatment. It is believed that a major portion of the currently unidentified risk factors is of genetic origin. Consistent with this idea, numerous potential risk alleles for stroke have been reported, however, the genetic evidence so far is not conclusive. The major goal of this review is to update the current knowledge about the genetic predisposition to the common multifactorial stroke, and to provide a bird's-eye view of this fast moving field. We selectively review and meta-analyze the related English literatures in public domain (PubMed) from 2000 onward, including the original reports and meta-analyses, to evaluate the genetic risk factors of common multifactorial stroke. The results indicated that we reviewed and meta-analyzed original reports and existing meta-analyses that studied the genetic predisposition to the common multifactorial stroke. Some original reports and meta-analyses were specific for ischemic stroke and others were for hemorrhagic stroke only. We also evaluated the major evolving issues in this field and discussed the future directions. In conclusion, strong evidences suggest that genetic risk factors contribute to common multifactorial stroke, and many genetic risk genes have been implicated in the literatures. However, not a single risk allele has been conclusively approved.