Notch1 Expression Research Articles

N6-Methyladenosine Reader YTHDF1 Promotes Stemness and Therapeutic Resistance in Hepatocellular Carcinoma by Enhancing NOTCH1 Expression.

Inhibition of YTHDF1 expression suppresses stemness of hepatocellular carcinoma cells and enhances sensitivity to targeted therapies, indicating that targeting YTHDF1 may be a promising therapeutic strategy for liver cancer.

Augmentation of scleral glycolysis promotes myopia through histone lactylation

Myopia is characterized of maladaptive increases in scleral fibroblast-to-myofibroblast transdifferentiation (FMT). Scleral hypoxia is a significant factor contributing to myopia, but how hypoxia induces myopia is poorly understood. Here, we showed that myopia in mice and guinea pigs was associated with hypoxia-induced increases in key glycolytic enzymes expression and lactate levels in the sclera. Promotion of scleral glycolysis or lactate production induced FMT and myopia; conversely, suppression of glycolysis or lactate production eliminated or inhibited FMT and myopia. Mechanistically, increasing scleral glycolysis-lactate levels promoted FMT and myopia via H3K18la, and this promoted Notch1 expression. Genetic analyses identified a significant enrichment of two genes encoding glycolytic enzymes, ENO2 and TPI1. Moreover, increasing sugar intake in guinea pigs not only induced myopia but also enhanced the response to myopia induction via the scleral glycolysis-lactate-histone lactylation pathway. Collectively, we suggest that scleral glycolysis contributes to myopia by promoting FMT via lactate-induced histone lactylation.

Tensile Stress-Activated and Exosome-Transferred YAP/TAZ-Notch Circuit Specifies Type H Endothelial Cell for Segmental Bone Regeneration.

The Ilizarov technique has been continuously innovated to utilize tensile stress (TS) for inducing a bone development-like regenerative process, aiming to achieve skeletal elongation and reconstruction. However, it remains uncertain whether this distraction osteogenesis (DO) process induced by TS involves the pivotal coupling of angiogenesis and osteogenesis mediated by type H endothelial cells (THECs). In this study, it is demonstrated that the Ilizarov technique induces the formation of a metaphysis-like architecture composed of THECs, leading to segmental bone regeneration during the DO process. Mechanistically, cell-matrix interactions-mediated activation of yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ) transcriptionally upregulates the expression of Notch1 and Delta-like ligand 4, which act as direct positive regulators of THECs phenotype, in bone marrow endothelial cells (BMECs) upon TS stimulation. Simultaneously, the Notch intracellular domain enhances YAP/TAZ activity by transcriptionally upregulating YAP expression and stabilizing TAZ protein, thus establishing the YAP/TAZ-Notch circuit. Additionally, TS-stimulated BMECs secrete exosomes enriched with vital molecules in this positive feedback pathway, which can be utilized to promote segmental bone defect healing, mimicking the therapeutic effects of Ilizarov technique. The findings advance the understanding of TS-induced segmental bone regeneration and establish the foundation for innovative biological therapeutic strategies aimed at activating THECs.

N-acetylcysteine protects against neurodevelopmental injuries induced by methylmercury exposure during pregnancy and lactation

As an extremely dangerous environmental contaminant, methylmercury (MeHg) results in detrimental health effects in human brain nervous system, one of its main targets. However, as a developmental toxicant, the brain of offspring is vulnerable to MeHg during pregnancy and lactation exposure. Unfortunately, mechanisms of neurodevelopmental injuries induced by MeHg have not been fully elucidated. N-acetylcysteine (NAC) has been used for several decades as an antioxidant to antagonize oxidative stress. However, the molecular mechanisms of NAC alleviating MeHg-induced neurodevelopmental toxicity are not clear. Here, for evaluation of the dose-dependent effects of MeHg exposure on neurodevelopmental injuries of offspring, and the possible protective effects of NAC, the pregnant female mice were exposed to MeHg (4, 8, 12 mg/L, respectively) and NAC (50, 100, 150 mg/kg, respectively) from gestational day 1 (GD1) to postnatal day 21 (PND21). Our results indicated that administering MeHg caused behavioral impairment and neuronal injuries in the cerebral cortex of newborn mice. MeHg dose-dependently caused reactive oxygen species (ROS) overproduction and oxidative stress aggravation, together with expression of Nrf2, HO-1, Notch1, and p21 up-regulation, and CDK2 inhibition. NAC treatment dose-dependently antagonized MeHg-induced oxidative stress that may contribute to alleviating neurobehavioral and neurodevelopmental impairments. These results give insight into that NAC can protect against MeHg-induced neurodevelopmental toxicity by its antioxidation capacity.

Study on the Mechanism of Notch Pathway Mediates the Role of Lenvatinib-resistant Hepatocellular Carcinoma Based on Organoids.

The emergence of treatment resistance has hindered the efficacy of targeted therapies used to treat patients with hepatocellular carcinoma (HCC). This study aimed to explore the mechanism of organoids constructed from lenvatinib-resistant HCC cells. Hep3B cell and human HCC organoids were cultured and identified using hematoxylin and eosin staining and Immunohistochemistry. Lenvatinib-sensitive/ resistant Hep3B cells were constructed using lenvatinib (0, 0.1, 1, and 10 μM) and lenvatinib (0, 1, 10, and 100 μM). qRT-PCR and flow cytometry were utilized to determine HCC stem cell markers CD44, CD90, and CD133 expressions. Transcriptome sequencing was performed on organoids.-Western blot evaluated Notch pathwayrelated proteins (NOTCH1 and Jagged) expressions. Furthermore, DAPT, an inhibitor of the Notch pathway, was used to investigate the effects of lenvatinib on resistance or stemness in organoids and human HCC tissues. The organoids were successfully cultivated. With the increase of lenvatinib concentration, sensitive cell organoids were markedly degraded and ATP activity was gradually decreased, while there was no significant change in ATP activity of resistant cell organoids. CD44 expressions were elevated after lenvatinib treatment compared with the control group. KEGG showed that lenvatinib treatment of organoids constructed from Hep3B cells mainly activated the Notch pathway. Compared with the control group, NOTCH1 and Jagged expressions elevated, and ATP activity decreased after lenvatinib treatment. However, ATP activity was notably decreased after DAPT treatment. Moreover, DAPT inhibited lenvatinib resistance and the increase in the expressions of CD44 caused by lenvatinib. Besides, 100 μM lenvatinib significantly inhibited the growth and ATP activity of human HCC organoids, and DAPT increased the inhibitory effect of lenvatinib. Lenvatinib regulated resistance and stemness in organoids via the Notch pathway.

Analysis of Notch1 protein expression in methotrexate-associated lymphoproliferative disorders.

Methotrexate (MTX)-associated lymphoproliferative disorder (MTX-LPD) is a lymphoproliferative disorder in patients treated with MTX. The mechanism of pathogenesis is still elusive, but it is thought to be a complex interplay of factors, such as underlying autoimmune disease activity, MTX use, Epstein-Barr virus infection, and aging. The NOTCH genes encode receptors for a signaling pathway that regulates various fundamental cellular processes, such as proliferation and differentiation during embryonic development. Mutations of NOTCH1 have been reported in B-cell tumors, including chronic lymphocytic leukemia/lymphoma, mantle cell lymphoma, and diffuse large B-cell lymphoma (DLBCL). Recently, it has also been reported that NOTCH1 mutations are found in post-transplant lymphoproliferative disorders, and in CD20-positive cells in angioimmunoblastic T-cell lymphoma, which might be associated with lymphomagenesis in immunodeficiency. In this study, to investigate the association of NOTCH1 in the pathogenesis of MTX-LPD, we evaluated protein expression of Notch1 in nuclei immunohistochemically in MTX-LPD cases [histologically DLBCL-type (n = 24) and classical Hodgkin lymphoma (CHL)-type (n = 24)] and de novo lymphoma cases [DLBCL (n = 19) and CHL (n = 15)]. The results showed that among MTX-LPD cases, the expression of Notch1 protein was significantly higher in the DLBCL type than in the CHL type (P < 0.001). In addition, among DLBCL morphology cases, expression of Notch1 tended to be higher in MTX-LPD than in the de novo group; however this difference was not significant (P = 0.0605). The results showed that NOTCH1 may be involved in the proliferation and tumorigenesis of B cells under the use of MTX. Further research, including genetic studies, is necessary.

Glycerophosphoinositol modulates FGA and NOTCH3 in exercise-induced muscle adaptation and colon cancer progression.

Fibroleukin (FGA) and NOTCH3 are vital in both exercise-induced muscle adaptation and colon adenocarcinoma (COAD) progression. This study aims to elucidate the roles of FGA and NOTCH3 in phenotypic variations of striated muscle induced by exercise and in COAD development. Additionally, it seeks to evaluate the prognostic significance of these proteins. Gene Set Variation Analysis (GSVA) and protein-protein interaction (PPI) network analysis were employed to identify differentially expressed genes (DEGs). Molecular docking studies were conducted to assess the binding affinities of 39 compounds to the NOTCH3 protein. In vitro assays, including mobileular viability, gene expression, and apoptosis assays, were performed to evaluate the effects of glycerophosphoinositol on FGA and NOTCH3 expression. Additionally, copy number variation (CNV), methylation status, and survival analyses were conducted across multiple cancers types. The NOTCH signaling pathway was consistently upregulated in exercise-induced muscle samples. High NOTCH3 expression was associated with poor prognosis in COAD, extracellular matrix organization, immune infiltration, and activation of the PI3K-Akt pathway. Molecular docking identified gamma-Glu-Trp, gamma-Glutamyltyrosine, and 17-Deoxycortisol as strong binders to NOTCH3. Glycerophosphoinositol treatment modulated FGA and NOTCH3 expression, influencing cell proliferation and apoptosis. CNV and methylation analyses revealed specific changes in FGA and NOTCH3 across 20 cancers types. Survival analyses showed strong associations between FGA/NOTCH3 expression and survival metrics, with negative correlations for FGA and positive correlations for NOTCH3. FGA and NOTCH3 play significant roles in exercise-induced muscle adaptation and colon cancer progression. The expression profiles and interactions of these proteins provide promising prognostic markers and therapeutic targets. These findings offer valuable insights into the post-translational modifications (PTMs) in human cancer, highlighting novel pharmacological and therapeutic opportunities.

Weaning causes imbalanced T lymphocyte distribution and impaired intestinal immune barrier function in piglets

Context The immune system of piglets is not fully developed at weaning. The immature adaptive immune system along with the change in the feed types and the living conditions make piglets susceptible to pathogenic infections, and result in diarrhoea and decreased growth. However, the underlying mechanisms require further research. Aims This study was conducted to investigate the effects of weaning on the growth performance and intestinal immune function of piglets. Methods In total, 40 piglets with similar bodyweights were selected in pairs at 21 days old and divided into the suckling group (SG, breastfed by their mothers) and weaning group (WG, weaned at 21 days old). Eight piglets from each group were randomly selected and sacrificed at 24 days (SG3 and WG3) and 28 days of age (SG7 and WG7). The growth performance, T lymphocyte subpopulations, the concentration of cytokines and immunoglobulins, and the expression of Notch2 signalling proteins were determined. Key results The weaning caused a decrease in bodyweight (P &lt; 0.01) and the ratio of CD3+CD4+/CD3+CD8+ T cells in the thymus (P &lt; 0.05). Compared with SG3, the concentration of secretory immunoglobulin A (sIgA) in the jejunum was decreased, and that of interleukin 2 (IL-2) in serum and ileum, IL-1β and IL-2 in jejunum were upregulated (P &lt; 0.01), while IL-10 in the small intestine was downregulated (P &lt; 0.05) in WG3. Weaning downregulated gene expression of IL-4 and upregulated gene expression of IL-1β, IL-12, and interferon γ (IFN-γ) in small intestine (P &lt; 0.05). Weaning downregulated protein expression of Notch2 and Hes1 but upregulated Jagged1 expression in small intestine of piglets (P &lt; 0.05). Conclusions Weaning caused an imbalance in T lymphocyte distribution, thus impairing the intestinal immune function of piglets, which might be associated with the Notch2 signalling. Furthermore, weaning caused adverse effects on piglets especially on the first 3 days, which were partly recovered after 3 days, but still existed at 7 days after weaning. Implications The results of this study may guide the pig-raising industry, especially for the management of piglets shortly after weaning.

Vitamin D/vitamin D receptor protects intestinal barrier against colitis by positively regulating Notch pathway.

Vitamin D/Vitamin D receptor (VD/VDR) signaling and the Notch pathway are involved in intestinal barrier restoration in colitis; however, their relationship and underlying mechanism are largely unknown. Therefore, this study aimed to investigate the role and mechanism of VD/VDR and the Notch pathways in intestinal barrier protection. Genetic Vdr knockout (VDR KO) and VD deficient (VDd) mice were established, and colitis was induced by feeding 2.5% dextran sodium sulfate (DSS) water. Mechanistic studies, including real-time PCR, immunofluorescence, Western blotting and dual-luciferase reporter assays, were performed on cultured Caco-2 cells and intestinal organoids. VD deficiency and VDR genetical KO increased the severity of DSS-induced colitis in mice, which presented a higher disease activity index score, increased intestinal permeability, and more severe intestinal histological damage than controls, accompanied by decreased and disrupted claudin-1 and claudin-3. Moreover, inhibition of Notch pathway by LY411,575 aggravated the severity of DSS-induced colitis and intestinal injury. In Caco-2 cells and intestinal organoids, the expression of Notch-1, N1ICD and Hes1 decreased upon downregulation or KO of VDR but increased upon paricalcitol (PAR, a VDR agonist) treatment. Meanwhile, PAR rescued claudin-1 and claudin-3 impairments that resulted from TNF-α exposure but failed to restore claudin-3 upon Notch inhibition. The dual-luciferase reporter assay further suggested that VD/VDR positively regulated the Notch signaling pathway by modulating Notch-1 transcription. VD/VDR positively modulates Notch activation by promoting Notch-1 transcription to maintain intestinal tight junction integrity and barrier function. This highlights the VD/VDR-Notch pathway as a potential new therapeutic target for protecting the intestinal barrier against ulcerative colitis.

Functional Enrichment Analysis of Tumor Microenvironment-Driven Molecular Alterations That Facilitate Epithelial-to-Mesenchymal Transition and Distant Metastasis.

Nowadays, hepatocellular carcinoma (HCC) is the second leading cause of cancer deaths, and identifying the effective factors in causing this disease can play an important role in its prevention and treatment. Tumors provide effective agents for invasion and metastasis to other organs by establishing appropriate communication between cancer cells and the microenvironment. Epithelial-to-mesenchymal transition (EMT) can be mentioned as one of the effective phenomena in tumor invasion and metastasis. Several factors are involved in inducing this phenomenon in the tumor microenvironment, which helps the tumor survive and migrate to other places. It can be effective to identify these factors in the use of appropriate treatment strategies and greater patient survival. This study investigated the molecular differences between tumor border cells and tumor core cells or internal tumor cells in HCC for specific EMT genes. Expression of NOTCH1, ID1, and LST1 genes showed a significant increase at the HCC tumor border. Targeting these genes can be considered as a useful therapeutic strategy to prevent distant metastasis in HCC patients.

Effects of crocin on the enhancement of in vitro neurogenesis: Involvement of Notch and CREB/BDNF signaling pathways.

Adult neurogenesis, the process of generating new neurons, continues throughout life. Unfortunately, this process is insufficient in pathological conditions and needs to be promoted. Crocin, the active component of saffron, affects neurogenesis in vivo and in vitro. We aimed to investigate the enhancing effects of crocin on the neurogenesis of adipose-derived mesenchymal stem cells in the presence of retinoic acid, as well as the molecular pathways involved. Differentiation capacities and stemness potential of harvested ADSCs were evaluated by differentiating into osteocytes and adipocytes, and expression of mesenchymal CD markers by flow cytometry. The optimum dose of crocin was assessed with an MTT assay. Crocin, retinoic acid, CREB/BDNF, and Notch inhibitors and their combination were added to the culture medium. Jag1, Hes1, Notch, and BDNF gene expression were analyzed by RT-PCR on days 7, 14, and 21, while CREB, DCX, SOX2, and NeuN expression were analyzed by immunofluorescence. Expression of mesenchymal CD markers as well as adipogenic and osteogenic differentiation confirmed the origin and properties of ADSCs. The optimal dose of crocin was 1 mM. Crocin significantly (P<0.05) increased, while inhibitors (DATP&Naphthol) significantly (P<0.05) decreased Jag1, Hes1, Notch, and BDNF expression. Immunofluorescent assessments showed that expression of DCX, BDNF, NeuN, and Sox2 proteins increased significantly (P<0.05) after crocin administration and decreased significantly (P<0.05) after inhibitor administration. Crocin can be used as an enhancer for neural differentiation of MSCs in vitro in the presence of retinoic acid. The mechanism is proposed through Notch and CREB/BDNF signaling pathways.

Low expression of Notch1 may be associated with acute myocardial infarction.

The transmembrane protein Notch1 is associated with cell growth, development, differentiation, proliferation, apoptosis, adhesion, and the epithelial mesenchymal transition. Proteomics, as a research method, uses a series of sequencing techniques to study the composition, expression levels, and modifications of proteins. Here, the association between Notch1 and acute myocardial infarction (AMI) was investigated using proteomics, to assess the possibility of using Notch1 as a biomarker for the disease. Fifty-five eligible patients with AMI and 74 with chronic coronary syndrome (CCS) were enrolled, representing the experimental and control groups, respectively. The mRNA levels were assessed using RT-qPCR and proteins were measured using ELISA, and the results were compared and analyzed. Notch1 mRNA levels were 0.52 times higher in the peripheral blood mononuclear cells of the AMI group relative to the CCS group (p < 0.05) while Notch1 protein levels were 0.63 times higher in peripheral blood plasma in AMI patients (p < 0.05). Notch1 levels were not associated with older age, hypertension, smoking, high abdominal-blood glucose, high total cholesterol, and high LDL in AMI. Logistic regression indicated associations between AMI and reduced Notch1 expression, hypertension, smoking, and high fasting glucose. Notch1 expression was reduced in the peripheral blood of patients with AMI relative to those with CCS. The low expression of Notch1 was found to be an independent risk factor for AMI and may thus be an indicator of the disease.

Inhibition of SUV39H1 reduces tumor angiogenesis via Notch1 in oral squamous cell carcinoma.

Targeting tumor angiogenesis is an important approach in advanced tumor therapy. Here we investigated the effect of the suppressor of variegation 3-9 homolog 1 (SUV39H1) on tumor angiogenesis in oral squamous cell carcinoma (OSCC). The GEPIA database was used to analyze the expression of SUV39H1 in various cancer tissues. The expression of SUV39H1 in OSCC was detected by immunohistochemistry, and the correlation between SUV39H1 and Notch1 and microvascular density (MVD) was analyzed. The effect of SUV39H1 inhibition on OSCC was investigated in vivo by chaetocin treatment. The migration and tube formation of vascular endothelial cells by conditioned culture-medium of different treatments of oral squamous cell cells were measured. The transcriptional level of SUV39H1 is elevated in various cancer tissues. The transcription level of SUV39H1 in head and neck squamous cell carcinoma was significantly higher than that in control. Immunohistochemistry result showed increased SUV39H1 expression in OSCC, which was significantly correlated with T staging. The expression of SUV39H1 was significantly correlated with Notch1 and CD31. In vivo experiment chaetocin treatment significantly inhibit the growth of tumor, and reduce SUV39H1, Notch1, CD31 expression. The decreased expression of SUV39H1 in OSCC cells lead to the decreased expression of Notch1 and VEGF proteins, as well as the decreased migration and tube formation ability of vascular endothelial cells. Inhibition of Notch1 further enhance this effect. Our results suggest inhibition of SUV39H1 may affect angiogenesis by regulating Notch1 expression. This study provides a foundation for SUV39H1 as a potential therapeutic target for OSCC.

Dishevelled-associated antagonist of β-catenin homolog 3 (DACT3) suppresses glioma progression though Notch1 signaling pathway in β-catenin-dependent manner

The disheveled-associated antagonist of β-catenin homolog 3 (DACT3) has been recognized as a tumor suppressor in various cancers. However, the function of DACT3 on glioma malignant progression along with potential molecular mechanisms is poorly clarified. This research aimed to investigate how DACT3 contributes to suppressing the progression of glioma. In our investigation, a pronounced decrease in DACT3 expression was observed in glioma tissues. Through the overexpression of DACT3, we noted a significant suppression in the proliferation, invasion, and migration of glioma cells, while concurrently observing an increase in cell adhesion. Our exploration into the molecular mechanisms revealed that DACT3 executes its tumor-suppressive role by impeding the expression of notch 1 intracellular domain (NICD) and translocating into the nucleus by downregulating the expression of β-catenin. Consequently, this process leads to the suppression of Notch1 signaling. To summarize, our findings reveal the function of DACT3 to inhibit glioma progression via the Notch1 signaling pathway in β-catenin dependent manner. This study stands as the pioneer in examining the role of DACT3 in glioma progression and comprehensively elucidating its molecular mechanisms in glioma development. Therefore, our results suggest that DACT3 holds promise as both a prognostic factor and a potential biomarker for guiding treatment strategies in glioma patients (Graphical Abstract).

CCL2- and Notch2-mediated Central Sensitization in a Rat Chronic Pelvic Pain Model.

Chronic pelvic pain (CPP) is a common gynecological condition in women with multifactorial etiology. Some studies have revealed that patients with CPP have the same structural and functional changes in the pain matrix in the brain to patients with other types of chronic pain. However, the relationship between localized pelvic pain and changes in the structure and function of the central nervous system is still unclear. In this study, a rat model of CPP was established by pelvic nerve ligation and behavioral tests were used to validate the model. Afterwards, we compared the expression of CCL2 in CPP and control rats and observed the changes in their behavioral patterns by blocking the expression of CCL2 in the former group. In addition, we upregulated the expression of CCL2 in human microglia cells (HMC3) to further observe the effect of CCL2 on the Notch2 pathway. Our results showed that the expression of chemokine ligand 2 (CCL2) in the serum exosomes, pelvic vascular endothelial cells, and cerebrospinal fluid was higher in the CPP group than the control group (p<0.05). In HMC3 treated with recombinant CCL2 protein, a significant increase in the mRNA and protein expression of Notch2 was observed. CCL2 can activate the Notch2 signaling pathway and plays an important role in the central sensitization of chronic pelvic pain.

Cooperation of Wnt/β-catenin and Dll1-mediated Notch pathway in Lgr5-positive intestinal stem cells regulates the mucosal injury and repair in DSS-induced colitis mice model.

Lgr5-positive cells located in the basal layer of crypts have self-regenerative and proliferative differentiation potentials of intestinal stem cells (ISCs), maintaining a balance of regeneration-repair in mucosal epithelium. However, the mechanisms of mucosal repair that are regulated by ISCs in ulcerative colitis (UC) remain unclear. Colon tissues from patients with UC were collected to test β-catenin and Notch1 expression by using Western blot and quantitative real-time polymerase chain reaction (PCR). β-cateninfl/fl mice, β-cateninTg mice, and Dll1tm1 Gos mice were used to cross with Lgr5-EGFP-IRES-creERT2 mice to generate mice of different genotypes, altering the activation of Wnt/β-catenin and Dll1-mediated Notch signaling in ISCs in vivo. Dextran sulfate sodium (DSS) was used to induce a colitis mice model. Intestinal organoids were isolated and cultured to observe the proliferation and differentiation levels of ISCs. β-catenin and Notch1 expression were significantly increased in the inflamed colon tissues from patients with UC. Wnt/β-catenin activation and Dll1-mediated Notch pathway inhibition in Lgr5-positive stem cells promoted the expressions of E-cadherin, CK20, and CHGA in colonic organoids and epithelium, implying the promotion of colonic epithelial integrity. Activation of Wnt/β-catenin and suppression of Dll1-mediated Notch pathway in Lgr5-positive ISCs alleviated the DSS-induced intestinal mucosal inflammation in mice. Lgr5-positive ISCs are characterized by self-renewal and high dividend potential, which play an important role in the injury and repair of intestinal mucosa. More importantly, the Wnt/β-catenin signaling pathway cooperates with the Notch signaling pathway to maintain the function of the Lgr5-positive ISCs.

NOTCH3 promotes docetaxel resistance of prostate cancer cells through regulating TUBB3 and MAPK signaling pathway.

Docetaxel is the preferred chemotherapeutic agent in patients with castrate-resistant prostate cancer (CRPC). However, patients eventually develop docetaxel resistance and in the absence of effective treatment options. Consequently, it is essential to investigate the mechanisms generating docetaxel resistance and develop novel alternative therapeutic targets. RNA sequencing was undertaken on docetaxel-sensitive and docetaxel-resistant prostate cancer (PCa) cells. Subsequently, chemoresistance, cancer stemness, and lipid metabolism were investigated. To obtain insight into the precise activities and action mechanisms of NOTCH3 in docetaxel-resistant PCa, immunoprecipitation, mass spectrometry, ChIP, luciferase reporter assay, cell metabolism, and animal experiments were performed. Through RNA sequencing analysis, we found that NOTCH3 expression was markedly higher in docetaxel-resistant cells relative to parental cells, and that this trend was continued in docetaxel-resistant PCa tissues. Experiments invitro and invivo revealed that NOTCH3 enhanced stemness, lipid metabolism, and docetaxel resistance in PCa. Mechanistically, NOTCH3 is bound to TUBB3 and activates the MAPK signaling pathway. Moreover, NOTCH3 was directly regulated by MEF2A in docetaxel-resistant cells. Notably, targeting NOTCH3 and the MEF2A/TUBB3 signaling axis was related to docetaxel chemoresistance in PCa. Overall, these results demonstrated that NOTCH3 fostered stemness, lipid metabolism, and docetaxel resistance in PCa via the TUBB3 and MAPK signaling pathways. Therefore, NOTCH3 may be employed as a prognostic biomarker in PCa patients. NOTCH3 could be a therapeutic target for PCa patients, particularly those who have developed docetaxel resistance.

Notch3 restricts metastasis of breast cancers through regulation of the JAK/STAT5A signaling pathway

PurposeTo explore the potential role of signal transducer and activator of transcription 5A (STAT5A) in the metastasis of breast cancer, and its mechanism of regulation underlying.Methods and resultsTCGA datasets were used to evaluate the expression of STAT5A in normal and different cancerous tissues through TIMER2.0, indicating that STAT5A level was decreased in breast cancer tissues compared with normal ones. Gene Set Enrichment Analysis predicted that STAT5A was associated with the activation of immune cells and cell cycle process. We further demonstrated that the infiltration of immune cells was positively associated with STAT5A level. Influorescence staining revealed the expression and distribution of F-actin was regulated by STAT5A, while colony formation assay, wound healing and transwell assays predicted the inhibitory role of STAT5A in the colony formation, migratory and invasive abilities in breast cancer cells. In addition, overexpression of the Notch3 intracellular domain (N3ICD), the active form of Notch3, resulted in the increased expression of STAT5A. Conversely, silencing of Notch3 expression by siNotch3 decreased STAT5A expression, supporting that STAT5A expression is positively associated with Notch3 in human breast cancer cell lines and breast cancer tissues. Mechanistically, chromatin immunoprecipitation showed that Notch3 was directly bound to the STAT5A promoter and induced the expression of STAT5A. Moreover, overexpressing STAT5A partially reversed the enhanced mobility of breast cancer cells following Notch3 silencing. Low expression of Notch3 and STAT5A predicted poorer prognosis of patients with breast cancer.ConclusionThe present study demonstrates that Notch3 inhibits metastasis in breast cancer through inducing transcriptionally STAT5A, which was associated with tumor-infiltrating immune cells, providing a novel strategy to treat breast cancer.

Cancer-associated fibroblasts-induced remodeling of tumor immune microenvironment via Jagged1 in glioma

Tumor immunosuppression are prominent characteristics of brain glioma. Current standard modality including surgical resection and chemoradiotherapy do not significantly improve clinical outcomes. Cancer-associated fibroblasts (CAFs) that regard as important stromal cells in tumor microenvironment have been confirmed to play crucial roles in tumor development. However, the effects of CAFs on tumor immunosuppression in glioma are not well expounded. In this study, we report that CAFs contributes to the formation of glioma immunosuppressive microenvironment. Specifically, we found that glioma-derived Jagged1 enhanced the proliferation and PD-L1 expression of CAFs in vitro. Importantly, we discovered that Notch1, c-Myc and PD-L1 expression were significantly increased in high Jagged1-expressing gliomas, moreover, we further confirmed that Notch1 and PD-L1 expression located on the CAFs in glioma tissues. We also found that glioma-derived Jagged1 promotes the increase of tumor-infiltrating macrophages, M2 macrophages and Foxp3 Treg cells, as well as no significance of M1 macrophages and CD8+ T cells, indicating potential immunosuppression. This study opens up novel therapeutic strategies reversing CAF immunosuppression for gliomas.

Specific knockout of notch-1 attenuates non-alcoholic fatty liver disease by promoting SHP2 phosphorylation.

To investigate the effect of Notch-1 signaling on NAFLD and its molecular mechanism. The lipid deposition in liver tissues was detected by oil red O staining. Western blotting was performed to detect the expressions of SREBP1C, SREBP2, LXR, IL-1β, IL-18, NLRP3, Notch-1, NOX2, NOX4, p-PI3K and p-SHP2 in macrophages, and the expressions of ALIX, CD9, IL-1β and SREBP1C in exosomes. Macrophages in the Notch-1MAC-KO group and Notch-1WT group were treated with FFA, and those in the Notch-1WT+FFA group and Notch-1MAC-KO+FFA group were treated with SHP2 inhibitors PHPS1 and Relaxin. It was observed by oil red O staining that lipid deposition in mice with NAFLD was reduced in the Notch-1MAC-KO group. The results of Western blotting showed that the expressions of ALIX, CD9, IL-1β and SREBP1C in macrophage exosomes were significantly lower in the Notch-1MAC-KO group than in the Notch-1WT group. In macrophages, the expressions of SREBP1C, SREBP2, LXR, IL-1β, IL-18, Notch-1, NOX2, NOX4 and p-PI3K significantly decreased, while the expression of p-SHP2 significantly increased in the Notch-1MAC-KO group compared with the Notch-1WT group. The Notch-1MAC-KO+FFA group had significantly decreased expressions of SREBP1C, NLRP3, IL-1β, IL-18, SREBP2, NOX2, NOX4 and p-PI3K and a significantly increased expression of p-SHP2 compared with the Notch-1WT+FFA group. However, the differences in the above proteins were all eliminated after PHPS1 and Relaxin were added. Specific knockout of Notch-1 attenuates NAFLD, and reduces inflammation and lipid deposition in the liver by promoting SHP2 phosphorylation.