Sample records for notch pathway inhibition

  1. Inhibition of Notch signaling alters the phenotype of orthotopic tumors formed from glioblastoma multiforme neurosphere cells but does not hamper intracranial tumor growth regardless of endogene Notch pathway signature.

    PubMed

    Kristoffersen, Karina; Nedergaard, Mette Kjølhede; Villingshøj, Mette; Borup, Rehannah; Broholm, Helle; Kjær, Andreas; Poulsen, Hans Skovgaard; Stockhausen, Marie-Thérése

    2014-07-01

    Brain cancer stem-like cells (bCSC) are cancer cells with neural stem cell (NSC)-like properties found in the devastating brain tumor glioblastoma multiforme (GBM). bCSC are proposed a central role in tumor initiation, progression, treatment resistance and relapse and as such present a promising target in GBM research. The Notch signaling pathway is often deregulated in GBM and we have previously characterized GBM-derived bCSC cultures based on their expression of the Notch-1 receptor and found that it could be used as predictive marker for the effect of Notch inhibition. The aim of the present project was therefore to further elucidate the significance of Notch pathway activity for the tumorigenic properties of GBM-derived bCSC. Human-derived GBM xenograft cells previously established as NSC-like neurosphere cultures were used. Notch inhibition was accomplished by exposing the cells to the gamma-secretase inhibitor DAPT prior to gene expression analysis and intracranial injection into immunocompromised mice. By analyzing the expression of several Notch pathway components, we found that the cultures indeed displayed different Notch pathway signatures. However, when DAPT-treated neurosphere cells were injected into the brain of immunocompromised mice, no increase in survival was obtained regardless of Notch pathway signature and Notch inhibition. We did however observe a decrease in the expression of the stem cell marker Nestin, an increase in the proliferative marker Ki-67 and an increased number of abnormal vessels in tumors formed from DAPT-treated, high Notch-1 expressing cultures, when compared with the control. Based on the presented results we propose that Notch inhibition partly induces differentiation of bCSC, and selects for a cell type that more strongly induces angiogenesis if the treatment is not sustained. However, this more differentiated cell type might prove to be more sensitive to conventional therapies.

  2. Interactions of Notch1 and TLR4 signaling pathways in DRG neurons of in vivo and in vitro models of diabetic neuropathy.

    PubMed

    Chen, Tianhua; Li, Hao; Yin, Yiting; Zhang, Yuanpin; Liu, Zhen; Liu, Huaxiang

    2017-11-02

    Understanding the interactions between Notch1 and toll-like receptor 4 (TLR4) signaling pathways in the development of diabetic peripheral neuropathy may lead to interpretation of the mechanisms and novel approaches for preventing diabetic neuropathic pain. In the present study, the interactions between Notch1 and TLR4 signaling pathways were investigated by using dorsal root ganglion (DRG) from diabetic neuropathic pain rats and cultured DRG neurons under high glucose challenge. The results showed that high glucose induced not only Notch1 mRNA, HES1 mRNA, and TLR4 mRNA expression, but also Notch1 intracellular domain (NICD1) and TLR4 protein expression in DRG neurons. The proportion of NICD1-immunoreactive (IR) and TLR4-IR neurons in DRG cultures was also increased after high glucose challenge. The above alterations could be partially reversed by inhibition of either Notch1 or TLR4 signaling pathway. Inhibition of either Notch1 or TLR4 signaling pathway could improve mechanical allodynia and thermal hyperalgesia thresholds. Inhibition of Notch1 or TLR4 signaling also decreased tumor necrosis factor-α (TNF-α) levels in DRG from diabetic neuropathic rats. These data imply that the interaction between Notch1 and TLR4 signaling pathways is one of the important mechanisms in the development or progression of diabetic neuropathy.

  3. Inhibition of Notch-1 pathway is involved in rottlerin-induced tumor suppressive function in nasopharyngeal carcinoma cells

    PubMed Central

    Hou, Yingying; Feng, Shaoyan; Wang, Lixia; Zhao, Zhe; Su, Jingna; Yin, Xuyuan; Zheng, Nana; Zhou, Xiuxia; Xia, Jun; Wang, Zhiwei

    2017-01-01

    Recent studies have revealed that rottlerin is a natural chemical drug to exert its anti-cancer activity. However, the molecular mechanisms of rottlerin-induced tumor suppressive function have not been fully elucidated. Notch signaling pathway has been characterized to play a crucial role in tumorigenesis. Therefore, regulation of Notch pathway could be beneficial for the treatment of human cancer. The aims of our current study were to explore whether rottlerin could suppress Notch-1 expression, which leads to inhibition of cell proliferation, migration and invasion in nasopharyngeal carcinoma cells. We performed several approaches, such as CTG, Flow cytometry, scratch healing assay, transwell and Western blotting. Our results showed that rottlerin treatment inhibited cell growth, migration and invasion, and triggered apoptosis, and arrested cell cycle to G1 phase. Moreover, the expression of Notch-1 was obvious decreased in nasopharyngeal carcinoma cells after rottlerin treatment. Importantly, overexpression of Notch-1 promoted cell growth and invasion, whereas down-regulation of Notch-1 inhibited cell growth and invasion in nasopharyngeal carcinoma cells. Notably, we found the over-expression of Notch-1 could abrogate the anti-cancer function induced by rottlerin. Strikingly, our study implied that Notch-1 could be a useful target of rottlerin for the prevention and treatment of human nasopharyngeal carcinoma. PMID:28977931

  4. Inhibition of ADAM-17 more effectively down-regulates the Notch pathway than that of γ-secretase in renal carcinoma.

    PubMed

    Guo, Zhen; Jin, Xunbo; Jia, Haiyan

    2013-05-09

    Our study is to research the effect of inhibited ADAM-17 expression through the Notch pathway in renal carcinoma. Immunohistochemistry and western blot were used to examine the expression of ADAM-17 protein in renal cancer tissues. Proliferation and cell invasion of 786-o cells, as well as OS-RC-2 cells, after treatment with two different inhibitors of the Notch pathway, were examined by CCK-8 assay and Transwell assay, respectively. 786-o cell apoptosis was measured using the FCM test. ADAM-17 was highly expressed in RCC tissues. Compared with blocking γ-secretase, a known mechanism of impairing Notch, blockade of ADAM-17 more effectively down-regulated the expressions of Notch1 and HES-1 proteins. Similarly, we found that the ADAM-17 inhibitor, Marimastat, could more efficiently reduce renal cell proliferation and invasive capacity in comparison with the γ-secretase inhibitor DAPT when used at the same dose. Similar results were obtained when apoptosis of 786-o was measured. Compared with γ-secretase, inhibition of ADAM-17 expression more effectively inhibits Notch pathway-mediated renal cancer cell proliferation and invasion. ADAM-17 may be a new target for future treatment of renal carcinoma.

  5. Non-canonical NOTCH3 signalling limits tumour angiogenesis.

    PubMed

    Lin, Shuheng; Negulescu, Ana; Bulusu, Sirisha; Gibert, Benjamin; Delcros, Jean-Guy; Ducarouge, Benjamin; Rama, Nicolas; Gadot, Nicolas; Treilleux, Isabelle; Saintigny, Pierre; Meurette, Olivier; Mehlen, Patrick

    2017-07-18

    Notch signalling is a causal determinant of cancer and efforts have been made to develop targeted therapies to inhibit the so-called canonical pathway. Here we describe an unexpected pro-apoptotic role of Notch3 in regulating tumour angiogenesis independently of the Notch canonical pathway. The Notch3 ligand Jagged-1 is upregulated in a fraction of human cancer and our data support the view that Jagged-1, produced by cancer cells, is inhibiting the apoptosis induced by the aberrant Notch3 expression in tumour vasculature. We thus present Notch3 as a dependence receptor inducing endothelial cell death while this pro-apoptotic activity is blocked by Jagged-1. Along this line, using Notch3 mutant mice, we demonstrate that tumour growth and angiogenesis are increased when Notch3 is silenced in the stroma. Consequently, we show that the well-documented anti-tumour effect mediated by γ-secretase inhibition is at least in part dependent on the apoptosis triggered by Notch3 in endothelial cells.

  6. Non-canonical NOTCH3 signalling limits tumour angiogenesis

    PubMed Central

    Lin, Shuheng; Negulescu, Ana; Bulusu, Sirisha; Gibert, Benjamin; Delcros, Jean-Guy; Ducarouge, Benjamin; Rama, Nicolas; Gadot, Nicolas; Treilleux, Isabelle; Saintigny, Pierre; Meurette, Olivier; Mehlen, Patrick

    2017-01-01

    Notch signalling is a causal determinant of cancer and efforts have been made to develop targeted therapies to inhibit the so-called canonical pathway. Here we describe an unexpected pro-apoptotic role of Notch3 in regulating tumour angiogenesis independently of the Notch canonical pathway. The Notch3 ligand Jagged-1 is upregulated in a fraction of human cancer and our data support the view that Jagged-1, produced by cancer cells, is inhibiting the apoptosis induced by the aberrant Notch3 expression in tumour vasculature. We thus present Notch3 as a dependence receptor inducing endothelial cell death while this pro-apoptotic activity is blocked by Jagged-1. Along this line, using Notch3 mutant mice, we demonstrate that tumour growth and angiogenesis are increased when Notch3 is silenced in the stroma. Consequently, we show that the well-documented anti-tumour effect mediated by γ-secretase inhibition is at least in part dependent on the apoptosis triggered by Notch3 in endothelial cells. PMID:28719575

  7. Overcoming failure to repair demyelination in EAE: gamma-secretase inhibition of Notch signaling.

    PubMed

    Jurynczyk, Maciej; Jurewicz, Anna; Bielecki, Bartosz; Raine, Cedric S; Selmaj, Krzysztof

    2008-02-15

    In multiple sclerosis (MS), myelin destroyed by the immune attack is not effectively repaired by oligodendrocytes (OLs) and MS foci eventually undergo glial scarring. Although oligodendrocyte precursor cells (OPCs) are normally recruited to the lesion areas, they fail to mature and remyelinate the damaged fibers. Activation of the Notch pathway has been shown to inhibit OPC differentiation and to hamper their ability to produce myelin during CNS development. We have recently shown that inhibition of gamma-secretase within the CNS of SJL/J mice with experimental autoimmune encephalomyelitis (EAE) blocks Notch pathway activation in OLs, promotes remyelination, reduces axonal damage and significantly enhances clinical recovery from the disease. Our results suggest that inhibiting the non-myelin permissive environment maintained by Notch pathways within the mature CNS offers a new strategy for treating autoimmune demyelination, including MS.

  8. Enhanced osteogenic differentiation of rat bone marrow mesenchymal stem cells on titanium substrates by inhibiting Notch3.

    PubMed

    Wang, Huiming; Jiang, Zhiwei; Zhang, Jing; Xie, Zhijian; Wang, Ying; Yang, Guoli

    2017-08-01

    The role of the Notch pathway has already been identified as a crucial regulator of bone development. However, the Notch signaling pathway has gone largely unexplored during osseointegration. This study aims to investigate the role of Notch signaling on osteogenic differentiation of rat derived bone marrow mesenchymal stem cells (BMSCs) on sandblasted, large-grit, acid-etched (SLA) treated Ti disks. The involved target genes in Notch pathways were identified by in vitro microarray and bioinformatics analyses with or without osteogenic induction. Adhesion, proliferation, and osteogenic related assay were subsequently conducted with target gene shRNA treatment. We found that 11 genes in the Notch signaling pathway were differentially expressed after osteogenic induction on SLA-treated Ti disks, which included up-regulated genes (Notch2, Dll1, Dll3, Ncstn, Ncor2, and Hes5) and down-regulated genes (Notch3, Lfng, Mfng, Jag2 and Maml2). With Notch3 shRNA treatment, the adhesion and proliferation of BMSCs on SLA-treated Ti disks were inhibited. Moreover, the expression levels of alkaline phosphatase (ALP), osteocalcin (OCN), calcium deposition, BMP2 and Runx2 increased significantly compared with that observed in control groups, suggesting that the function of Notch3 was inhibitory in the osteogenic differentiation of BMSCs on SLA-treated titanium. Inhibition Notch3 can enhance osteogenic differentiation of BMSCs on SLA-treated Ti disks, which potentially provides a gene target for improving osseointegration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Therapeutic antibody targeting of individual Notch receptors.

    PubMed

    Wu, Yan; Cain-Hom, Carol; Choy, Lisa; Hagenbeek, Thijs J; de Leon, Gladys P; Chen, Yongmei; Finkle, David; Venook, Rayna; Wu, Xiumin; Ridgway, John; Schahin-Reed, Dorreyah; Dow, Graham J; Shelton, Amy; Stawicki, Scott; Watts, Ryan J; Zhang, Jeff; Choy, Robert; Howard, Peter; Kadyk, Lisa; Yan, Minhong; Zha, Jiping; Callahan, Christopher A; Hymowitz, Sarah G; Siebel, Christian W

    2010-04-15

    The four receptors of the Notch family are widely expressed transmembrane proteins that function as key conduits through which mammalian cells communicate to regulate cell fate and growth. Ligand binding triggers a conformational change in the receptor negative regulatory region (NRR) that enables ADAM protease cleavage at a juxtamembrane site that otherwise lies buried within the quiescent NRR. Subsequent intramembrane proteolysis catalysed by the gamma-secretase complex liberates the intracellular domain (ICD) to initiate the downstream Notch transcriptional program. Aberrant signalling through each receptor has been linked to numerous diseases, particularly cancer, making the Notch pathway a compelling target for new drugs. Although gamma-secretase inhibitors (GSIs) have progressed into the clinic, GSIs fail to distinguish individual Notch receptors, inhibit other signalling pathways and cause intestinal toxicity, attributed to dual inhibition of Notch1 and 2 (ref. 11). To elucidate the discrete functions of Notch1 and Notch2 and develop clinically relevant inhibitors that reduce intestinal toxicity, we used phage display technology to generate highly specialized antibodies that specifically antagonize each receptor paralogue and yet cross-react with the human and mouse sequences, enabling the discrimination of Notch1 versus Notch2 function in human patients and rodent models. Our co-crystal structure shows that the inhibitory mechanism relies on stabilizing NRR quiescence. Selective blocking of Notch1 inhibits tumour growth in pre-clinical models through two mechanisms: inhibition of cancer cell growth and deregulation of angiogenesis. Whereas inhibition of Notch1 plus Notch2 causes severe intestinal toxicity, inhibition of either receptor alone reduces or avoids this effect, demonstrating a clear advantage over pan-Notch inhibitors. Our studies emphasize the value of paralogue-specific antagonists in dissecting the contributions of distinct Notch receptors to differentiation and disease and reveal the therapeutic promise in targeting Notch1 and Notch2 independently.

  10. [Notch signaling pathway participates in the differentiation of hepatic progenitor cells into bile duct epithelial cells and progression of hepatic fibrosis in cholestatic liver fibrosis rat].

    PubMed

    Mu, Y P; Zhang, X; Xu, Y; Fan, W W; Li, X W; Chen, J M; Chen, G F; Liu, P

    2017-06-08

    Objective: To investigate differentiation direction of hepatic progenitor cells (HPCs) in cholestatic liver fibrosis (CLF), and the role of Notch signaling pathway in the differentiation of HPCs. Methods: A CLF rat model was established by bile duct ligation (BDL) followed by monitoring changes of Notch signal pathway and the cellular origin of proliferating cholangiocytes. After intraperitoneal injection of DAPT (a Notch signaling inhibitor) after bile duct ligation, the progress of liver fibrosis and the proliferation of cholangiocytes after inhibition of the Notch pathway were analyzed. Results: Data showed that bile duct proliferation gradually increased along with inflammatory cell infiltration and proliferating bile duct cells surrounded by abundant collagen in the BDL group. Immunostaining confirmed markedly increased expression of CK19, OV6, Sox9 and EpCAM. In addition, RT-PCR results showed that Notch signaling pathway was activated significantly. Once the Notch signaling pathway was inhibited by DAPT, bile duct proliferation markedly suppressed along with significantly decreased the mRNA expression of CK19, OV6, Sox9 and EpCAM, compared with BDL group [(10.2±0.7) vs . (22.3±0.8), (7.6±1.5) vs . (18.1±3.7), (1.4±0.4) vs . (4.1±1.1), (1.3±0.3) vs . (5.0±1.4), respectively, P <0.01]. Moreover, liver fibrosis was also reduced significantly. Conclusion: Notch signaling activation is required for HPCs differentiation into cholangiocytes in CLF and inhibition of the Notch signaling pathway may offer a therapeutic option for treating CLF.

  11. Total alkaloids of Rubus alceifolius Poir inhibit tumor angiogenesis through suppression of the Notch signaling pathway in a mouse model of hepatocellular carcinoma.

    PubMed

    Zhao, Jinyan; Lin, Wei; Cao, Zhiyun; Zhuang, Qunchuan; Zheng, Liangpu; Peng, Jun; Hong, Zhenfeng

    2015-01-01

    Angiogenesis, which has a critical role in human tumor growth and development, is tightly regulated by the Notch signaling pathway. Total alkaloids are active components of the plant Rubus alceifolius Poir, which is used for the treatment of various types of cancer. A previous study by our group showed that the total alkaloids of Rubus alceifolius Poir (TARAP) induced hepatocellular carcinoma (HCC) cell apoptosis through the activation of the mitochondria-dependent pathway in vitro and in vivo, as well as inhibited angiogenesis in a chick embryo chorioallantoic membrane model. In the present study, to further analyze the specific mechanisms underlying the antitumor activity of TARAP, a HCC xenograft mouse model was used to assess the effect of TARAP on angiogenesis in vivo. TARAP was found to suppress the expression of vascular endothelial growth factor (VEGF) A and VEGF receptor-2 in tumor tissues, which resulted in the inhibition of tumor angiogenesis. In addition, TARAP treatment was observed to inhibit the expression of Notch1, delta-like ligand 4 and jagged 1, which are key mediators of the Notch signaling pathway. The present study identified that the inhibition of tumor angiogenesis through the suppression of the Notch signaling pathway may be one of the mechanisms through which TARAP may be effective in the treatment of cancer.

  12. Advanced glycation end product-induced astrocytic differentiation of cultured neurospheres through inhibition of Notch-Hes1 pathway-mediated neurogenesis.

    PubMed

    Guo, Yijing; Wang, Pin; Sun, Haixia; Cai, Rongrong; Xia, Wenqing; Wang, Shaohua

    2013-12-23

    This study aims to investigate the roles of the Notch-Hes1 pathway in the advanced glycation end product (AGE)-mediated differentiation of neural stem cells (NSCs). We prepared pLentiLox3.7 lentiviral vectors that express short hairpin RNA (shRNA) against Notch1 and transfected it into NSCs. Cell differentiation was analyzed under confocal laser-scanning microscopy. The percentage of neurons and astrocytes was quantified by normalizing the total number of TUJ1+ (Neuron-specific class III β-tubulin) and GFAP+ (Glial fibrillary acidic protein) cells to the total number of Hoechst 33342-labeled cell nuclei. The protein and gene expression of Notch-Hes1 pathway components was examined via western blot analysis and real-time PCR. After 1 week of incubation, we found that AGE-bovine serum albumin (BSA) (400 μg/mL) induced the astrocytic differentiation of cultured neurospheres and inhibited neuronal formation. The expression of Notch-Hes1 pathway components was upregulated in the cells in the AGE-BSA culture medium. Immunoblot analysis indicated that shRNA silencing of Notch1 expression in NSCs significantly increases neurogenesis and suppresses astrocytic differentiation in NSCs incubated with AGE-BSA. AGEs promote the astrocytic differentiation of cultured neurospheres by inhibiting neurogenesis through the Notch-Hes1 pathway, providing a potential therapeutic target for hyperglycemia-related cognitive deficits.

  13. PI3K/AKT signaling inhibits NOTCH1 lysosome-mediated degradation.

    PubMed

    Platonova, Natalia; Manzo, Teresa; Mirandola, Leonardo; Colombo, Michela; Calzavara, Elisabetta; Vigolo, Emilia; Cermisoni, Greta Chiara; De Simone, Daria; Garavelli, Silvia; Cecchinato, Valentina; Lazzari, Elisa; Neri, Antonino; Chiaramonte, Raffaella

    2015-06-06

    The pathways of NOTCH and PI3K/AKT are dysregulated in about 60% and 48% of T-cell acute lymphoblastic leukemia (T-ALL) patients, respectively. In this context, they interact and cooperate in controlling tumor cell biology. Here, we propose a novel mechanism by which the PI3K/AKT pathway regulates NOTCH1 in T-ALL, starting from the evidence that the inhibition of PI3K/AKT signaling induced by treatment with LY294002 or transient transfection with a dominant negative AKT mutant downregulates NOTCH1 protein levels and activity, without affecting NOTCH1 transcription. We showed that the withdrawal of PI3K/AKT signaling was associated to NOTCH1 phosphorylation in tyrosine residues and monoubiquitination of NOTCH1 detected by Ubiquitin capture assay. Co-immunoprecipitation assay and colocalization analysis further showed that the E3 ubiquitin ligase c-Cbl interacts and monoubiquitinates NOTCH1, activating its lysosomal degradation. These results suggest that the degradation of NOTCH1 could represent a mechanism of control by which NOTCH1 receptors are actively removed from the cell surface. This mechanism is finely regulated by the PI3K/AKT pathway in physiological conditions. In pathological conditions characterized by PI3K/AKT hyperactivation, such as T-ALL, the excessive AKT signaling could lead to NOTCH1 signaling dysregulation. Therefore, a therapeutic strategy directed to PI3K/AKT in T-ALL could contemporaneously inhibit the dysregulated NOTCH1 signaling. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  14. IL6 blockade potentiates the anti-tumor effects of γ-secretase inhibitors in Notch3-expressing breast cancer.

    PubMed

    Wang, Dong; Xu, Jiahui; Liu, Bingjie; He, Xueyan; Zhou, Lei; Hu, Xin; Qiao, Feng; Zhang, Anli; Xu, Xiaojun; Zhang, Huafeng; Wicha, Max S; Zhang, Lixing; Shao, Zhi-Ming; Liu, Suling

    2018-02-01

    Notch pathways have important roles in carcinogenesis including pathways involving the Notch1 and Notch2 oncogenes. Pan-Notch inhibitors, such as gamma secretase inhibitors (GSIs), have been used in the clinical trials, but the outcomes of these trials have been insufficient and have yielded unclear. In the present study, we demonstrated that GSIs, such as MK-0752 and RO4929097, inhibit breast tumor growth, but increase the breast cancer stem cell (BCSC) population in Notch3-expressing breast cancer cells, in a process that is coupled with IL6 induction and is blocked by the IL6R antagonist Tocilizumab (TCZ). IL6 induction results from inhibition of Notch3-Hey2 signaling through MK-0752. Furthermore, HIF1α upregulates Notch3 expression via direct binding to the Notch3 promoter and subsequently downregulates BCSCs by decreasing the IL6 levels in Notch3-expressing breast cancer cells. Utilizing both breast cancer cell line xenografts and patient-derived xenografts (PDX), we showed that the combination of MK-0752 and Tocilizumab significantly decreases BCSCs and inhibits tumor growth and thus might serve as a novel therapeutic strategy for treating women with Notch3-expressing breast cancers.

  15. A critical role of Notch signaling in osteosarcoma invasion and metastasis

    PubMed Central

    Zhang, Pingyu; Yang, Yanwen; Zweidler-McKay, Patrick A.; Hughes, Dennis P.M.

    2010-01-01

    Purpose Notch signaling is an important mediator of growth and survival in several cancer types, with Notch pathway genes functioning as oncogenes or tumor suppressors in different cancers. However, the role of Notch in osteosarcoma is unknown. Experimental Design We assessed the expression of Notch pathway genes in human osteosarcoma cell lines and patient samples. We then employed pharmacologic and retroviral manipulation of the Notch pathway and studied the impact on osteosarcoma cell proliferation, survival, anchorage-independent growth, invasion and metastasis in vitro and in vivo. Results Notch pathway genes, including Notch ligand DLL1, Notch 1 and 2, and the Notch target gene HES1 were expressed in osteosarcoma cells, and expression of HES1 was associated with invasive and metastatic potential. Blockade of Notch pathway signaling with a small molecule inhibitor of gamma secretase eliminated invasion in matrigel without affecting cell proliferation, survival, or anchorage-independent growth. Manipulation of Notch and HES1 signaling demonstrated a crucial role for HES1 in osteosarcoma invasiveness and metastasis in vivo. Conclusion These studies identify a new invasion and metastasis-regulating pathway in osteosarcoma and define a novel function for the Notch pathway: regulation of metastasis. Since the Notch pathway can be inhibited pharmacologically, these findings point toward possible new treatments to reduce invasion and metastasis in osteosarcoma. PMID:18483362

  16. ALK1 Signaling Inhibits Angiogenesis by Cooperating with the Notch Pathway

    PubMed Central

    Larrivée, Bruno; Prahst, Claudia; Gordon, Emma; del Toro, Raquel; Mathivet, Thomas; Duarte, Antonio; Simons, Michael; Eichmann, Anne

    2014-01-01

    SUMMARY Activin receptor-like kinase 1 (ALK1) is an endothelial-specific member of the TGF-β/BMP receptor family that is inactivated in patients with hereditary hemorrhagic telangiectasia (HHT). How ALK1 signaling regulates angiogenesis remains incompletely understood. Here we show that ALK1 inhibits angiogenesis by cooperating with the Notch pathway. Blocking Alk1 signaling during postnatal development in mice leads to retinal hypervascularization and the appearance of arteriovenous malformations (AVMs). Combined blockade of Alk1 and Notch signaling further exacerbates hypervascularization, whereas activation of Alk1 by its high-affinity ligand BMP9 rescues hypersprouting induced by Notch inhibition. Mechanistically, ALK1-dependent SMAD signaling synergizes with activated Notch in stalk cells to induce expression of the Notch targets HEY1 and HEY2, thereby repressing VEGF signaling, tip cell formation, and endothelial sprouting. Taken together, these results uncover a direct link between ALK1 and Notch signaling during vascular morpho-genesis that may be relevant to the pathogenesis of HHT vascular lesions. PMID:22421041

  17. Notch3 inhibits epithelial–mesenchymal transition by activating Kibra-mediated Hippo/YAP signaling in breast cancer epithelial cells

    PubMed Central

    Zhang, X; Liu, X; Luo, J; Xiao, W; Ye, X; Chen, M; Li, Y; Zhang, G-J

    2016-01-01

    Invasion, metastasis and chemoresistance are leading causes of death in breast cancer patients. A vital change of epithelial cells, epithelial–mesenchymal transition (EMT), is involved in these processes. Unfortunately, the molecular mechanisms controlling EMT remain to be elucidated. Our previous studies have shown that ectopic N3ICD expression inhibits EMT in MDA-MB-231, a triple-negative breast cancer (TNBC) epithelial cell line. To decipher the mechanism, we performed in-depth studies. Specifically, we found that overexpressing N3ICD transcriptionally upregulated the expression of Kibra, an upstream member of the Hippo pathway. Correspondingly, we also observed that phosphorylated Hippo pathway core kinases, including Lats1/2 and MST1/2, were increased and decreased by overexpressing and knocking down Notch3, respectively. Furthermore, we found that the oncogenic transcriptional coactivator yes-associated protein (YAP), which is negatively regulated by the Hippo pathway, was inhibited by overexpressing N3ICD in breast cancer epithelial cells. The ability of Kibra to inhibit EMT has been previously reported. We thus speculated that Notch3 inhibition of EMT is mediated by upregulated Kibra. To verify this hypothesis, a rescue experiment was performed. Evidently, the ability of Notch3 to inhibit EMT can be countered by knocking down Kibra expression. These data suggest that Notch3 inhibits EMT by activating the Hippo/YAP pathway by upregulating Kibra in breast cancer epithelial cells, and Kibra may be a downstream effector of Notch3. These findings deepen our understanding of EMT in both development and disease, and will undoubtedly help to provide new therapeutic strategies for interfering with cancer invasion and metastasis, especially for TNBC. PMID:27841855

  18. Emodin suppresses TGF-β1-induced epithelial-mesenchymal transition in alveolar epithelial cells through Notch signaling pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, Rundi; Chen, Ruilin; Cao, Yu

    Pulmonary fibrosis is characterized by the destruction of lung tissue architecture and the formation of fibrous foci, currently has no satisfactory treatment. Emodin is a component of Chinese herb that has been reported to be medicament on pancreatic fibrosis and liver fibrosis. However, its role in pulmonary fibrosis has not been established yet. In the present study, we investigated the hypothesis that Emodin plays an inhibitory role in TGF-β1 induced epithelial-mesenchymal transition (EMT) of alveolar epithelial cell, and Emodin exerts its effect through the Notch signaling pathway. Emodin inhibits the proliferation of Rat alveolar type II epithelial cells RLE-6TN inmore » a concentration-dependent manner; reduces the expression of Collagen I, α-SMA and Vimentin, promotes the expression of E-cadherin. Moreover, Emodin could regulate the expression patterns of the Notch signaling pathway-related factors and reduce the Notch-1 nucleus translocation. Knockdown of Notch-1 enhances the inhibitory effect of Emodin on TGF-β1-induced EMT in RLE-6TN cells. In conclusion, the data of the present study suggests that Emodin suppresses TGF-β1-induced EMT in alveolar epithelial cells through Notch signaling pathway and shows the potential to be effective in the treatment of pulmonary fibrosis. - Highlights: • Emodin inhibits TGF-β1-induced EMT in alveolar epithelial cells. • Emodin regulates the expression patterns of the Notch signaling pathway-related factors. • Emodin inhibits TGF-β1-induced Notch-1 nucleus translocation and activation.« less

  19. Targeting the Notch signaling pathway in autoimmune diseases.

    PubMed

    Ma, Daoxin; Zhu, Yuanchao; Ji, Chunyan; Hou, Ming

    2010-05-01

    The Notch signaling pathway regulates a variety of processes and has been linked to diverse effects. Aberrant Notch function is important in several disorders. Pre-clinical studies have suggested that inhibition of Notch is an attractive approach to treat hematologic and solid malignancies. Many patients with refractory autoimmune diseases respond poorly to therapy and have significant morbidity and the treatment is highly toxic, so more effective therapies for autoimmune diseases are being examined. The role of the Notch pathway and therapeutic strategies targeting it in many illnesses, especially autoimmune diseases. The Notch pathway has unique and attractive advantages for targeting. Targeting it has already been trialed in many experiments, which may show better efficacy and fewer side effects compared with classical drugs for the treatment. Targeting Notch might provide etiological rather than symptomatic treatment. Various methods targeting the Notch pathway have been under investigation. Rational targeting of the Notch signaling pathway in cancer and some autoimmune diseases has proven to be successful. Classical drugs for the treatment of autoimmune diseases are inefficient and toxic to some extent, and targeting the Notch pathway is a promising therapeutic concept. However, there are still many questions about targeting Notch in autoimmune diseases, and further investigation will be needed.

  20. Cellular Notch responsiveness is defined by phosphoinositide 3-kinase-dependent signals

    PubMed Central

    Mckenzie, Grahame; Ward, George; Stallwood, Yvette; Briend, Emmanuel; Papadia, Sofia; Lennard, Andrew; Turner, Martin; Champion, Brian; Hardingham, Giles E

    2006-01-01

    Background Notch plays a wide-ranging role in controlling cell fate, differentiation and development. The PI3K-Akt pathway is a similarly conserved signalling pathway which regulates processes such as differentiation, proliferation and survival. Mice with disrupted Notch and PI3K signalling show phenotypic similarities during haematopoietic cell development, suggesting functional interaction between these pathways. Results We show that cellular responsiveness to Notch signals depends on the activity of the PI3K-Akt pathway in cells as diverse as CHO cells, primary T-cells and hippocampal neurons. Induction of the endogenous PI3K-Akt pathway in CHO cells (by the insulin pathway), in T-cells (via TCR activation) or in neurons (via TrKB activation) potentiates Notch-dependent responses. We propose that the PI3K-Akt pathway exerts its influence on Notch primarily via inhibition of GSK3-beta, a kinase known to phosphorylate and regulate Notch signals. Conclusion The PI3K-Akt pathway acts as a "gain control" for Notch signal responses. Since physiological levels of intracellular Notch are often low, coincidence with PI3K-activation may be crucial for induction of Notch-dependent responses. PMID:16507111

  1. ALK1 signaling inhibits angiogenesis by cooperating with the Notch pathway.

    PubMed

    Larrivée, Bruno; Prahst, Claudia; Gordon, Emma; del Toro, Raquel; Mathivet, Thomas; Duarte, Antonio; Simons, Michael; Eichmann, Anne

    2012-03-13

    Activin receptor-like kinase 1 (ALK1) is an endothelial-specific member of the TGF-β/BMP receptor family that is inactivated in patients with hereditary hemorrhagic telangiectasia (HHT). How ALK1 signaling regulates angiogenesis remains incompletely understood. Here we show that ALK1 inhibits angiogenesis by cooperating with the Notch pathway. Blocking Alk1 signaling during postnatal development in mice leads to retinal hypervascularization and the appearance of arteriovenous malformations (AVMs). Combined blockade of Alk1 and Notch signaling further exacerbates hypervascularization, whereas activation of Alk1 by its high-affinity ligand BMP9 rescues hypersprouting induced by Notch inhibition. Mechanistically, ALK1-dependent SMAD signaling synergizes with activated Notch in stalk cells to induce expression of the Notch targets HEY1 and HEY2, thereby repressing VEGF signaling, tip cell formation, and endothelial sprouting. Taken together, these results uncover a direct link between ALK1 and Notch signaling during vascular morphogenesis that may be relevant to the pathogenesis of HHT vascular lesions. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Alterations in Notch signalling in skeletal muscles from mdx and dko dystrophic mice and patients with Duchenne muscular dystrophy.

    PubMed

    Church, Jarrod E; Trieu, Jennifer; Chee, Annabel; Naim, Timur; Gehrig, Stefan M; Lamon, Séverine; Angelini, Corrado; Russell, Aaron P; Lynch, Gordon S

    2014-04-01

    New Findings What is the central question of this study? The Notch signalling pathway plays an important role in muscle regeneration, and activation of the pathway has been shown to enhance muscle regeneration in aged mice. It is unknown whether Notch activation will have a similarly beneficial effect on muscle regeneration in the context of Duchenne muscular dystrophy (DMD). What is the main finding and its importance? Although expression of Notch signalling components is altered in both mouse models of DMD and in human DMD patients, activation of the Notch signalling pathway does not confer any functional benefit on muscles from dystrophic mice, suggesting that other signalling pathways may be more fruitful targets for manipulation in treating DMD. Abstract In Duchenne muscular dystrophy (DMD), muscle damage and impaired regeneration lead to progressive muscle wasting, weakness and premature death. The Notch signalling pathway represents a central regulator of gene expression and is critical for cellular proliferation, differentiation and apoptotic signalling during all stages of embryonic muscle development. Notch activation improves muscle regeneration in aged mice, but its potential to restore regeneration and function in muscular dystrophy is unknown. We performed a comprehensive examination of several genes involved in Notch signalling in muscles from dystrophin-deficient mdx and dko (utrophin- and dystrophin-null) mice and DMD patients. A reduction of Notch1 and Hes1 mRNA in tibialis anterior muscles of dko mice and quadriceps muscles of DMD patients and a reduction of Hes1 mRNA in the diaphragm of the mdx mice were observed, with other targets being inconsistent across species. Activation and inhibition of Notch signalling, followed by measures of muscle regeneration and function, were performed in the mouse models of DMD. Notch activation had no effect on functional regeneration in C57BL/10, mdx or dko mice. Notch inhibition significantly depressed the frequency-force relationship in regenerating muscles of C57BL/10 and mdx mice after injury, indicating reduced force at each stimulation frequency, but enhanced the frequency-force relationship in muscles from dko mice. We conclude that while Notch inhibition produces slight functional defects in dystrophic muscle, Notch activation does not significantly improve muscle regeneration in murine models of muscular dystrophy. Furthermore, the inconsistent expression of Notch targets between murine models and DMD patients suggests caution when making interspecies comparisons.

  3. Regulation of podocyte lesions in diabetic nephropathy via miR-34a in the Notch signaling pathway.

    PubMed

    Zhang, Xiangying; Song, Shuping; Luo, Huixin

    2016-11-01

    The activation of the Notch signaling pathway has been shown to play an important role in diabetic nephropathy (DN) development. Besides, Notch-1 is a target gene in miR-34a. However, the regulation of the podocyte lesions involved in DN by miR-34a has not been identified. This study utilized miR-34a mimics and small interfering RNA transfection to construct miR-34a overexpression and lower-expression model to investigate the effect of miR-34a on the regulation of the Notch signaling pathway and podocyte lesions in DN. Western blotting and real-time quantitative polymerase chain reaction were applied for the quantitative testing of mRNA and protein expression. Apoptosis of podocyte was detected by TUNEL staining. In high-glucose (HG) conditions, miR-34a overexpression inhibited the expression of Notch 1, Jagged 1, NICD, Hes 1, and Hey 1 proteins. Further, cleaved caspase-3, Bax, and phosphorylation of p53 (p-p53) were reduced significantly. Therefore, miR-34a overexpression inhibited the Notch signaling pathway and podocyte lesions induced by HG. β-arrestin was slightly reduced in HG conditions. Meanwhile, miR-34a overexpression could remit the inhibition. Results from this study provide evidence that miR-34a may offer a new approach for the treatment of diabetes.

  4. [Mechanism of Chlorogenic Acid in Apoptotic Regulation through Notch1 
Pathway in Non-small Cell Lung Carcinoma in Animal Level].

    PubMed

    Li, Wei; Liu, Xu; Zhang, Guoqian; Zhang, Linlin

    2017-08-20

    It has been proven that chlorogenic acids can produce anticancer effects by regulating cell cycle, inducing apoptosis, inhibiting cell growth, Notch signaling pathways are closely related to many human tumors. The aim of this study is to study the mechanism of chlorogenic acid on apoptosis of non-small lung cancer through Notch1 pathway in animal level, and hope to provide theory basis on clinical treatment and research aimed at targeting Notch1 signaling in non-small cell carcinoma (NSCLC). MTT assay was used to evaluate the A549 cell proliferation under the treatment of chlorogenic acid. The effect of chlorogenic acid on apoptotic and cell cycle were detected by flow cytometry. The animal model of A549 cell transplanted in nude was established, tumer size and weight were detected. The mRNA level of Notch1 signal pathway related facter were detected by RT-PCR; the expression of Notch1 signal pathway related facter in tumor tissue was detected by western blot. Chlorogenic acid inhibited the A549 cell proliferation. incresed cell apoptotic and cell percentagein G2/M (P<0.05), and in a dose-dependent manner. In animal model, tumer size and weight were lower than control group, the difference was statistically significant (P<0.05). The relative expression of mRNA of Notch1, VEGF, Delta4, HES1 and HEY1 were decreaced (P<0.05) in tumor tissue which treated with chlorogenic. The expression of Notch1 were decreaced, PTEN, p-PTEN, p-AKT were increced significantly in tumor tissue which treated with chlorogenic (P<0.05). Chlorogenic acid can regulate theapoptosis of non-small lung cancer through Notch pathway in animal level, which may be associated with the down-regulating the expression of VEGF and Delta4. Notch pathway may cross talk with PI3K/AKT pathway through PTEN in NSCLC.

  5. Effects of cell penetrating Notch inhibitory peptide conjugated to elastin-like polypeptide on glioblastoma cells.

    PubMed

    Opačak-Bernardi, Teuta; Ryu, Jung Su; Raucher, Drazen

    2017-07-01

    Notch pathway was found to be activated in most glioblastomas (GBMs), underlining the importance of Notch in formation and recurrence of GBM. In this study, a Notch inhibitory peptide, dominant negative MAML (dnMAML), was conjugated to elastin-like polypeptide (ELP) for tumor targeted delivery. ELP is a thermally responsive polypeptide that can be actively and passively targeted to the tumor site by localized application of hyperthermia. This complex was further modified with the addition of a cell penetrating peptide, SynB1, for improved cellular uptake and blood-brain barrier penetration. The SynB1-ELP1-dnMAML was examined for its cellular uptake, cytotoxicity, apoptosis, cell cycle inhibition and the inhibition of target genes' expression. SynB1-ELP1-dnMAML inhibited the growth of D54 and U251 cells by inducing apoptosis and cell cycle arrest, especially in the presence of hyperthermia. Hyperthermia increased overall uptake of the polypeptide by the cells and enhanced the resulting pharmacological effects of dnMAML, showing the inhibition of targets of Notch pathway such as Hes-1 and Hey-L. These results confirm that dnMAML is an effective Notch inhibitor and combination with ELP may allow thermal targeting of the SynB1-ELP1-dnMAML complex in cancer cells while avoiding the dangers of systemic Notch inhibition.

  6. Effect of Notch and PARP Pathways' Inhibition in Leukemic Cells.

    PubMed

    Horvat, Luka; Antica, Mariastefania; Matulić, Maja

    2018-06-14

    Differentiation of blood cells is one of the most complex processes in the body. It is regulated by the action of transcription factors in time and space which creates a specific signaling network. In the hematopoietic signaling system, Notch is one of the main regulators of lymphocyte development. The aim of this study was to get insight into the regulation of Notch signalization and the influence of poly(ADP-ribose)polymerase (PARP) activity on this process in three leukemia cell lines obtained from B and T cells. PARP1 is an enzyme involved in posttranslational protein modification and chromatin structure changes. B and T leukemia cells were treated with Notch and PARP inhibitors, alone or in combination, for a prolonged period. The cells did not show cell proliferation arrest or apoptosis. Analysis of gene and protein expression set involved in Notch and PARP pathways revealed increase in JAGGED1 expression after PARP1 inhibition in B cell lines and changes in Ikaros family members in both B and T cell lines after γ-secretase inhibition. These data indicate that Notch and PARP inhibition, although not inducing differentiation in leukemia cells, induce changes in signaling circuits and chromatin modelling factors.

  7. Association between high levels of Notch3 expression and high invasion and poor overall survival rates in pancreatic ductal adenocarcinoma.

    PubMed

    Zhou, Jin-Xue; Zhou, Liang; Li, Qing-Jun; Feng, Wen; Wang, Pei-Min; Li, Er-Feng; Gong, Wen-Jing; Kou, Ming-Wen; Gou, Wei-Ting; Yang, Yan-Ling

    2016-11-01

    Pancreatic ductal adenocarcinoma (PDAC) is a commonly fatal tumour. It is characterized by early metastasis and high mortality. Many patients die as a result of PDAC tumour progression. However, the underlying mechanism of invasion and metastasis in PDAC is still not fully understood. Previous studies showed that the Notch signalling pathway may play an important role in the progression of tumour invasion and metastasis. However, it is not yet known whether the Notch signalling pathway participates in the progression of invasion in PDAC. In the present study, immunohistochemistry showed that a high expression of Notch3 was correlated with tumour grade, metastasis, venous invasion and American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) stage. Kaplan-Meier curves suggested that a high expression of Notch3 was a significant risk factor for shortened survival time. We also showed that inhibition of Notch3 had an anti‑invasion role in PDAC cells. In vitro, the inhibition of Notch3 reduced the migration and invasion capabilities of PDAC cells by regulating the expressions of E-cadherin, CD44v6, MMP-2, MMP-9, VEGF and uPA via regulating the COX-2 and ERK1/2 pathways. These results indicated that downregulation of the Notch signalling pathway may be a novel and useful approach for preventing and treating PDAC invasion.

  8. Inhibition of gamma-secretase activity impedes uterine serous carcinoma growth in a human xenograft model.

    PubMed

    Groeneweg, Jolijn W; Hall, Tracilyn R; Zhang, Ling; Kim, Minji; Byron, Virginia F; Tambouret, Rosemary; Sathayanrayanan, Sriram; Foster, Rosemary; Rueda, Bo R; Growdon, Whitfield B

    2014-06-01

    Uterine serous carcinoma (USC) represents an aggressive subtype of endometrial cancer. We sought to understand Notch pathway activity in USC and determine if pathway inhibition has anti-tumor activity. Patient USC tissue blocks were obtained and used to correlate clinical outcomes with Notch1 expression. Three established USC cell lines were treated with gamma-secretase inhibitor (GSI) in vitro. Mice harboring cell line derived or patient derived USC xenografts (PDXs) were treated with vehicle, GSI, paclitaxel and carboplatin (P/C), or combination GSI and P/C. Levels of cleaved Notch1 protein and Hes1 mRNA were determined in GSI treated samples. Statistical analysis was performed using the Wilcoxon rank sum and Kaplan-Meier methods. High nuclear Notch1 protein expression was observed in 58% of USC samples with no correlation with overall survival. GSI induced dose-dependent reductions in cell number and decreased levels of cleaved Notch1 protein and Hes1 mRNA in vitro. Treatment of mice with GSI led to decreased Hes1 mRNA expression in USC xenografts. In addition, GSI impeded tumor growth of cell line xenografts as well as UT1 USC PDXs. When GSI and P/C were combined, synergistic anti-tumor activity was observed in UT1 xenografts. Notch1 is expressed in a large subset of USC. GSI-mediated Notch pathway inhibition led to both reduced cell numbers in vitro and decreased tumor growth of USC some xenograft models. When combined with conventional chemotherapy, GSI augmented anti-tumor activity in one USC PDX line suggesting that targeting of the Notch signaling pathway is a potential therapeutic strategy for future investigation. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. γ-Secretase inhibitor enhances antitumour effect of radiation in Notch-expressing lung cancer

    PubMed Central

    Mizugaki, H; Sakakibara-Konishi, J; Ikezawa, Y; Kikuchi, J; Kikuchi, E; Oizumi, S; Dang, T P; Nishimura, M

    2012-01-01

    Background: Notch receptor has an important role in both development and cancer. We previously reported that inhibition of the Notch3 by γ-secretase inhibitor (GSI) induces apoptosis and suppresses tumour proliferation in non-small-cell lung cancer. Although radiation is reported to induce Notch activation, little is known about the relationship between radiation and Notch pathway. Methods: We examined the effect of combining GSI and radiation at different dosing in three Notch expressing lung cancer cell lines. The cytotoxic effect of GSI and radiation was evaluated using MTT assay and clonogenic assay in vitro and xenograft models. Expressions of Notch pathway, mitogen-activated protein kinase (MAPK) pathway and Bcl-2 family proteins were investigated using western blot analysis. Results: We discovered that the antitumour effect of combining GSI and radiation was dependent on treatment schedule. γ-Secretase inhibitor administration after radiation had the greatest growth inhibition of lung cancer in vitro and in vivo. We showed that the combination induced apoptosis of lung cancer cell lines through the regulation of MAPK and Bcl-2 family proteins. Furthermore, activation of Notch after radiation was ameliorated by GSI administration, suggesting that treatment with GSI prevents Notch-induced radiation resistance. Conclusion: Notch has an important role in lung cancer. Treatment with GSI after radiation can significantly enhance radiation-mediated tumour cytotoxicity. PMID:22596234

  10. Fatty Acid-binding Protein 4, a Point of Convergence for Angiogenic and Metabolic Signaling Pathways in Endothelial Cells*

    PubMed Central

    Harjes, Ulrike; Bridges, Esther; McIntyre, Alan; Fielding, Barbara A.; Harris, Adrian L.

    2014-01-01

    Fatty acid-binding protein 4 (FABP4) is an adipogenic protein and is implicated in atherosclerosis, insulin resistance, and cancer. In endothelial cells, FABP4 is induced by VEGFA, and inhibition of FABP4 blocks most of the VEGFA effects. We investigated the DLL4-NOTCH-dependent regulation of FABP4 in human umbilical vein endothelial cells by gene/protein expression and interaction analyses following inhibitor treatment and RNA interference. We found that FABP4 is directly induced by NOTCH. Stimulation of NOTCH signaling with human recombinant DLL4 led to FABP4 induction, independently of VEGFA. FABP4 induction by VEGFA was reduced by blockade of DLL4 binding to NOTCH or inhibition of NOTCH signal transduction. Chromatin immunoprecipitation of the NOTCH intracellular domain showed increased binding to two specific regions in the FABP4 promoter. The induction of FABP4 gene expression was dependent on the transcription factor FOXO1, which was essential for basal expression of FABP4, and FABP4 up-regulation following stimulation of the VEGFA and/or the NOTCH pathway. Thus, we show that the DLL4-NOTCH pathway mediates endothelial FABP4 expression. This indicates that induction of the angiogenesis-restricting DLL4-NOTCH can have pro-angiogenic effects via this pathway. It also provides a link between DLL4-NOTCH and FOXO1-mediated regulation of endothelial gene transcription, and it shows that DLL4-NOTCH is a nodal point in the integration of pro-angiogenic and metabolic signaling in endothelial cells. This may be crucial for angiogenesis in the tumor environment. PMID:24939870

  11. Activation of Notch1 inhibits medial edge epithelium apoptosis in all-trans retinoic acid-induced cleft palate in mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Yadong; Dong, Shiyi; Wang, Weicai

    Administration of all-trans retinoic acid (atRA) on E12.0 (embryonic day 12.0) leads to failure of medial edge epithelium (MEE) disappearance and cleft palate. However, the molecular mechanism underlying the relationship between atRA and MEE remains to be identified. In this study, atRA (200 mg/kg) administered by gavage induced a 75% incidence of cleft palate in C57BL/6 mice. Notch1 was up-regulated in MEE cells in the atRA-treated group compared with the controls at E15.0, together with reduced apoptosis and elevated proliferation. Next, we investigated the mechanisms underlying atRA, Notch1 and MEE degradation in palate organ culture. Our results revealed that down-regulation ofmore » Notch1 partially rescued the inhibition of atRA-induced palate fusion. Molecular analysis indicated that atRA increased the expression of Notch1 and Rbpj and decreased the expression of P21. In addition, depletion of Notch1 expression decreased the expression of Rbpj and increased the expression of P21. Moreover, inhibition of Rbpj expression partially reversed atRA-induced MEE persistence and increased P21 expression. These findings demonstrate that atRA inhibits MEE degradation, which in turn induces a cleft palate, possibly through the Notch1/RBPjk/P21 signaling pathway. - Highlights: • atRA exposure on E12.0 induced MEE persistence and cleft palate. • Notch1 was up-regulated in MEE cells in the atRA-treated embryos. • atRA inhibits MEE degradation, which in turn induces cleft palate, possibly through the Notch1/RBPjk/P21 signaling pathway.« less

  12. Therapeutic targeting of NOTCH1 signaling in T-ALL

    PubMed Central

    Palomero, Teresa; Ferrando, Adolfo

    2010-01-01

    The recent identification of activating mutations in NOTCH1 in the majority of T-cell acute lymphoblastic leukemias (T-ALL) has brought major interest towards targeting the NOTCH signaling pathway in this disease. Small molecule γ-secretase inhibitors (GSIs) which block a critical proteolytic step required for NOTCH1 activation can effectively block the activity of NOTCH1 mutant alleles. However, the clinical development of GSIs has been hampered by their low cytotoxicity against human T-ALL and the development of significant gastrointestinal toxicity derived from inhibition of NOTCH signaling in the gut. Improved understanding of the oncogenic mechanisms of NOTCH1 and the effects of NOTCH inhibition in leukemic cells and the intestinal epithelium are required for the design of effective anti-NOTCH1 therapies in T-ALL. PMID:19778842

  13. Triptolide prevents extracellular matrix accumulation in experimental diabetic kidney disease by targeting microRNA-137/Notch1 pathway.

    PubMed

    Han, Fei; Wang, Shanshan; Chang, Yunpeng; Li, Chunjun; Yang, Juhong; Han, Zhe; Chang, Baocheng; Sun, Bei; Chen, Liming

    2018-03-01

    MicroRNAs (miRNAs) are involved in multiple biological functions via suppressing target genes. Triptolide is a monomeric compound isolated from a traditional Chinese herb, which exerts protective roles in many kinds of glomerular diseases. However, our understanding of the triptolide effect on miRNAome is still limited. In this study, we found that triptolide significantly decreased albuminuria and improved glomerulosclerosis in rats with diabetic kidney disease (DKD). And triptolide also inhibited extracellular matrix (ECM) protein accumulation and the notch1 pathway activation under diabetic conditions. MiR-137 was significantly decreased in the HG (high glucose)-treated HRMCs and in the kidney tissues of the diabetic rats, but was upregulated by triptolide. In addition, overexpression of miR-137 exerted similar effects to those of triptolide, while miR-137 inhibition aggravated ECM protein accumulation. Luciferase reporter assay results demonstrated that miR-137 directly targets Notch1. Furthermore, the miR-137-dependent effects were due to Notch1 suppression that in turn inhibited ECM protein expression, key mediators of glomerulosclerosis. Finally, downregulation of miR-137 reversed the ECM inhibition role of triptolide in HG cultured HRMCs. Taken together, these findings indicate that triptolide is a potential therapeutic option for DKD and that miR-137/Notch1 pathway play roles in the anti-glomerulosclerosis mechanism of triptolide. © 2017 Wiley Periodicals, Inc.

  14. Evidence of functional cross talk between the Notch and NF-κB pathways in nonneoplastic hyperproliferating colonic epithelium.

    PubMed

    Ahmed, Ishfaq; Roy, Badal; Chandrakesan, Parthasarathy; Venugopal, Anand; Xia, Lijun; Jensen, Roy; Anant, Shrikant; Umar, Shahid

    2013-02-15

    The Notch and NF-κB signaling pathways regulate stem cell function and inflammation in the gut, respectively. We investigate whether a functional cross talk exists between the two pathways during transmissible murine colonic hyperplasia (TMCH) caused by Citrobacter rodentium (CR). During TMCH, NF-κB activity and subunit phosphorylation in colonic crypts of NIH Swiss mice at days 6 and 12 were associated with increases in downstream target CXC chemokine ligand (CXCL)-1/keratinocyte-derived chemokine (KC) expression. Blocking Notch signaling acutely for 5 days with the Notch blocker dibenzazepine (DBZ) failed to inhibit crypt NF-κB activity or CXCL-1/KC expression. Chronic DBZ administration for 10 days, however, blocked Notch and NF-κB signaling in the crypts and abrogated hyperplasia. Intriguingly, chronic Notch inhibition was associated with significant increases in IL-1α, granulocyte colony-stimulating factor, monocyte chemoattractant protein 1, macrophage inflammatory protein 2, and KC in the crypt-denuded lamina propria or whole distal colon, with concomitant increases in myeloperoxidase activity. In core-3(-/-) mice, which are defective in intestinal mucin, DBZ administration replicated the results of NIH Swiss mice; in Apc(Min/+) mice, which are associated with CR-induced elevation of NF-κB-p65(276) expression, DBZ reversed the increase in NF-κB-p65(276), which may have blocked rapid proliferation of the mutated crypts. DBZ further blocked reporter activities involving the NF-κB-luciferase reporter plasmid or the Toll-like receptor 4/NF-κB/SEAPorter HEK-293 reporter cell line, while ectopic expression of Notch-N(ICD) reversed the inhibitory effect. Dietary bael (Aegle marmelos) extract (4%) and curcumin (4%) restored Notch and NF-κB cross talk in NIH Swiss mice, inhibited CR/DBZ-induced apoptosis in the crypts, and promoted crypt regeneration. Thus functional cross talk between the Notch and NF-κB pathways during TMCH regulates hyperplasia and/or inflammation in response to CR infection.

  15. Nuclear factor of activated T-cells 5 increases intestinal goblet cell differentiation through an mTOR/Notch signaling pathway

    PubMed Central

    Zhou, Yuning; Wang, Qingding; Weiss, Heidi L.; Evers, B. Mark

    2014-01-01

    The intestinal mucosa undergoes a continual process of proliferation, differentiation, and apoptosis that is regulated by multiple signaling pathways. Previously, we have shown that the nuclear factor of activated T-cells 5 (NFAT5) is involved in the regulation of intestinal enterocyte differentiation. Here we show that treatment with sodium chloride (NaCl), which activates NFAT5 signaling, increased mTORC1 repressor regulated in development and DNA damage response 1 (REDD1) protein expression and inhibited mTOR signaling; these alterations were attenuated by knockdown of NFAT5. Knockdown of NFAT5 activated mammalian target of rapamycin (mTOR) signaling and significantly inhibited REDD1 mRNA expression and protein expression. Consistently, overexpression of NFAT5 increased REDD1 expression. In addition, knockdown of REDD1 activated mTOR and Notch signaling, whereas treatment with mTOR inhibitor rapamycin repressed Notch signaling and increased the expression of the goblet cell differentiation marker mucin 2 (MUC2). Moreover, knockdown of NFAT5 activated Notch signaling and decreased MUC2 expression, while overexpression of NFAT5 inhibited Notch signaling and increased MUC2 expression. Our results demonstrate a role for NFAT5 in the regulation of mTOR signaling in intestinal cells. Importantly, these data suggest that NFAT5 participates in the regulation of intestinal homeostasis via the suppression of mTORC1/Notch signaling pathway. PMID:25057011

  16. Notch pathway activity identifies cells with cancer stem cell-like properties and correlates with worse survival in lung adenocarcinoma

    PubMed Central

    Hassan, Khaled A.; Wang, Luo; Korkaya, Hasan; Chen, Guoan; Maillard, Ivan; Beer, David G.; Kalemkerian, Gregory P.; Wicha, Max S.

    2013-01-01

    Purpose The cancer stem cell theory postulates that tumors contain a subset of cells with stem cell properties of self-renewal, differentiation and tumor-initiation. The purpose of this study is to determine the role of Notch activity in identifying lung cancer stem cells. Experimental Design We investigated the role of Notch activity in lung adenocarcinoma utilizing a Notch GFP-reporter construct and a gamma-secretase inhibitor (GSI), which inhibits Notch pathway activity. Results Transduction of lung cancer cells with Notch GFP-reporter construct identified a subset of cells with high Notch activity (GFP-bright). GFP-bright cells had the ability to form more tumor spheres in serum-free media, and were able to generate both GFP-bright and GFP-dim (lower Notch activity) cell populations. GFP-bright cells were resistant to chemotherapy and were tumorigenic in serial xenotransplantation assays. Tumor xenografts of mice treated with GSI had decreased expression of downstream effectors of Notch pathway and failed to regenerate tumors upon reimplantation in NOD/SCID mice. Using multivariate analysis, we detected a statistically significant correlation between poor clinical outcome and Notch activity (reflected in increased Notch ligand expression or decreased expression of the negative modulators), in a group of 441 lung adenocarcinoma patients. This correlation was further confirmed in an independent group of 89 adenocarcinoma patients where Hes-1 overexpression correlated with poor overall survival. Conclusions Notch activity can identify lung cancer stem cell-like population and its inhibition may be an appropriate target for treating lung adenocarcinoma. PMID:23444212

  17. Atractylenolide I-mediated Notch pathway inhibition attenuates gastric cancer stem cell traits

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ma, Li; Mao, Rurong; Shen, Ke

    Highlights: • This paper supports the anti-tumor effects of AT-I on gastric cancer in vitro. • AT-I attenuates gastric cancer stem cell traits. • It is the systematic study regarding AT-I suppression of Notch pathway in GC and GCSLCs. - Abstract: Atractylenolide I (AT-I), one of the main naturally occurring compounds of Rhizoma Atractylodis Macrocephalae, has remarkable anti-cancer effects on various cancers. However, its effects on the treatment of gastric cancer remain unclear. Via multiple cellular and molecular approaches, we demonstrated that AT-I could potently inhibit cancer cell proliferation and induce apoptosis through inactivating Notch pathway. AT-I treatment led tomore » the reduction of expressions of Notch1, Jagged1, and its downstream Hes1/ Hey1. Our results showed that AT-I inhibited the self-renewal capacity of gastric stem-like cells (GCSLCs) by suppression of their sphere formation capacity and cell viability. AT-I attenuated gastric cancer stem cell (GCSC) traits partly through inactivating Notch1, leading to reducing the expressions of its downstream target Hes1, Hey1 and CD44 in vitro. Collectively, our results suggest that AT-I might develop as a potential therapeutic drug for the treatment of gastric cancer.« less

  18. Parkin mediates neuroprotection through activation of Notch1 signaling.

    PubMed

    Yoon, Ji-Hye; Ann, Eun-Jung; Kim, Mi-Yeon; Ahn, Ji-Seon; Jo, Eun-Hye; Lee, Hye-Jin; Lee, Hye-Won; Lee, Young Chul; Kim, Jeong-Sun; Park, Hee-Sae

    2017-02-04

    Parkin, an E3 ubiquitin ligase, is the most frequently mutated gene in hereditary Parkinson's disease. Inactivation of Parkin leads to impairment of the ubiquitin-proteasome system, resulting in the accumulation of misfolded or aggregated proteins and ensuing neurodegeneration. In this study, we show that Parkin positively regulates the Notch1 signaling pathway. Overexpression of Parkin stabilized Notch1-IC protein levels, whereas knockdown of Parkin decreased Notch1-IC protein stability. Notably, overexpression of Parkin disrupted oxidative stress-induced apoptosis in neuronal cells. However, knockdown of Notch1 inhibited Parkin-induced neuronal cell survival. Together, these results indicate that Parkin is a novel regulator of the Notch1 signaling pathway, which promotes neuronal cell survival.

  19. The role of the PTEN/AKT Pathway in NOTCH1-induced leukemia

    PubMed Central

    Palomero, Teresa; Dominguez, Maria; Ferrando, Adolfo A.

    2008-01-01

    Activating mutations in NOTCH1 are the most prominent genetic abnormality in T-cell acute Lymphoblastic Leukemia (T-ALL) and inhibition of NOTCH1 signaling with γ-secretase inhibitors (GSIs) has been proposed as targeted therapy in this disease. However, most T-ALL cell lines with mutations in NOTCH1 fail to respond to GSI therapy. Using gene expression profiling and mutation analysis we showed that mutational loss of PTEN is a common event in T-ALL and is associated with resistance to NOTCH inhibition. Furthermore, our studies revealed that NOTCH1 induces upregulation of the PI3K-AKT pathway via HES1, which negatively controls the expression of PTEN. This regulatory circuitry is evolutionary conserved from Drosophila to humans as demonstrated by the interaction of overexpression of Delta and Akt in a model of Notch-induced transformation in the fly eye. Loss of PTEN and constitutive activation of AKT in T-ALL induce increased glucose metabolism and bypass the requirement of NOTCH1 signaling to sustain cell growth. Importantly, PTEN-null/GSI resistant T-ALL cells switch their oncogene addiction from NOTCH1 to AKT and are highly sensitive to AKT inhibitors. These results should facilitate the development of molecular therapies targeting NOTCH1 and AKT for the treatment of T-ALL. PMID:18414037

  20. Blocking the NOTCH pathway can inhibit the growth of CD133-positive A549 cells and sensitize to chemotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Juntao; Mao, Zhangfan; Huang, Jie

    2014-02-21

    Highlights: • Notch signaling pathway members are expressed lower levels in CD133+ cells. • CD133+ cells are not as sensitive as CD133− cells to chemotherapy. • GSI could inhibit the growth of both CD133+ and CD133− cells. • Blockade of Notch signaling pathway enhanced the effect of chemotherapy with CDDP. • DAPT/CDDP co-therapy caused G2/M arrest and elimination in CD133+ cells. - Abstract: Cancer stem cells (CSCs) are believed to play an important role in tumor growth and recurrence. These cells exhibit self-renewal and proliferation properties. CSCs also exhibit significant drug resistance compared with normal tumor cells. Finding new treatmentsmore » that target CSCs could significantly enhance the effect of chemotherapy and improve patient survival. Notch signaling is known to regulate the development of the lungs by controlling the cell-fate determination of normal stem cells. In this study, we isolated CSCs from the human lung adenocarcinoma cell line A549. CD133 was used as a stem cell marker for fluorescence-activated cell sorting (FACS). We compared the expression of Notch signaling in both CD133+ and CD133− cells and blocked Notch signaling using the γ-secretase inhibitor DAPT (GSI-IX). The effect of combining GSI and cisplatin (CDDP) was also examined in these two types of cells. We observed that both CD133+ and CD133− cells proliferated at similar rates, but the cells exhibited distinctive differences in cell cycle progression. Few CD133+ cells were observed in the G{sub 2}/M phase, and there were half as many cells in S phase compared with the CD133− cells. Furthermore, CD133+ cells exhibited significant resistance to chemotherapy when treated with CDDP. The expression of Notch signaling pathway members, such as Notch1, Notch2 and Hes1, was lower in CD133+ cells. GSI slightly inhibited the proliferation of both cell types and exhibited little effect on the cell cycle. The inhibitory effects of DPP on these two types of cells were enhanced when combined with GSI. Interestingly, this effect was especially significant in CD133+ cells, suggesting that Notch pathway blockade may be a useful CSC-targeted therapy in lung cancer.« less

  1. Inhibition of Notch1 promotes hedgehog signalling in a HES1-dependent manner in chondrocytes and exacerbates experimental osteoarthritis.

    PubMed

    Lin, Neng-Yu; Distler, Alfiya; Beyer, Christian; Philipi-Schöbinger, Ariella; Breda, Silvia; Dees, Clara; Stock, Michael; Tomcik, Michal; Niemeier, Andreas; Dell'Accio, Francesco; Gelse, Kolja; Mattson, Mark P; Schett, Georg; Distler, Jörg Hw

    2016-11-01

    Notch ligands and receptors have recently been shown to be differentially expressed in osteoarthritis (OA). We aim to further elucidate the functional role of Notch signalling in OA using Notch1 antisense transgenic (Notch1 AS) mice. Notch and hedgehog signalling were analysed by real-time PCR and immunohistochemistry. Notch-1 AS mice were employed as a model of impaired Notch signalling in vivo. Experimental OA was induced by destabilisation of the medial meniscus (DMM). The extent of cartilage destruction and osteophyte formation was analysed by safranin-O staining with subsequent assessment of the Osteoarthritis Research Society International (OARSI) and Mankin scores and µCT scanning. Collagen X staining was used as a marker of chondrocyte hypertrophy. The role of hairy/enhancer of split 1 (Hes-1) was investigated with knockdown and overexpression experiments. Notch signalling was activated in human and murine OA with increased expression of Jagged1, Notch-1, accumulation of the Notch intracellular domain 1 and increased transcription of Hes-1. Notch1 AS mice showed exacerbated OA with increases in OARSI scores, osteophyte formation, increased subchondral bone plate density, collagen X and osteocalcin expression and elevated levels of Epas1 and ADAM-TS5 mRNA. Inhibition of the Notch pathway induced activation of hedgehog signalling with induction of Gli-1 and Gli-2 and increased transcription of hedgehog target genes. The regulatory effects of Notch signalling on Gli-expression were mimicked by Hes-1. Inhibition of Notch signalling activates hedgehog signalling, enhances chondrocyte hypertrophy and exacerbates experimental OA including osteophyte formation. These data suggest that the activation of the Notch pathway may limit aberrant hedgehog signalling in OA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Inhibitory effect of CT domain of CCN3/NOV on proliferation and differentiation of osteogenic mesenchymal stem cells, Kusa-A1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Katsuki, Yuko; Oral Pathology, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549; Sakamoto, Kei

    CCN3/NOV activates the Notch signal through the carboxyl terminal cysteine-rich (CT) domain. CCN3 transfection to Kusa-A1 inhibited osteogenic differentiation and cell proliferation, which is accompanied by upregulation of Hes/Hey, Notch downstream targets, and p21, a CDK inhibitor. Upregulation of Hes/Hey and p21 was abrogated by the deletion of CT domain. Anti-proliferative activity of CCN3 was also abrogated by CT domain deletion whereas anti-osteogenic activity was not completely abrogated. We found that CT domain-deleted CCN3 still possesses antagonistic effect on BMP-2. These results suggest that CCN3 employs Notch and BMP pathways in anti-osteogenic activity while it inhibits cell proliferation uniquely bymore » Notch/p21 pathway.« less

  3. Monomeric C-reactive protein and Notch-3 co-operatively increase angiogenesis through PI3K signalling pathway.

    PubMed

    Boras, Emhamed; Slevin, Mark; Alexander, M Yvonne; Aljohi, Ali; Gilmore, William; Ashworth, Jason; Krupinski, Jerzy; Potempa, Lawrence A; Al Abdulkareem, Ibrahim; Elobeid, Adila; Matou-Nasri, Sabine

    2014-10-01

    C-reactive protein (CRP) is the most acute-phase reactant serum protein of inflammation and a strong predictor of cardiovascular disease. Its expression is associated with atherosclerotic plaque instability and the formation of immature micro-vessels. We have previously shown that CRP upregulates endothelial-derived Notch-3, a key receptor involved in vascular development, remodelling and maturation. In this study, we investigated the links between the bioactive monomeric CRP (mCRP) and Notch-3 signalling in angiogenesis. We used in vitro (cell counting, wound-healing and tubulogenesis assays) and in vivo (chorioallantoic membrane) angiogenic assays and Western blotting to study the angiogenic signalling pathways induced by mCRP and Notch-3 activator chimera protein (Notch-3/Fc). Our results showed an additive effect on angiogenesis of mCRP stimulatory effect combined with Notch-3/Fc promoting bovine aortic endothelial cell (BAEC) proliferation, migration, tube formation in Matrigel(TM) with up-regulation of phospho-Akt expression. The pharmacological blockade of PI3K/Akt survival pathway by LY294002 fully inhibited in vitro and in vivo angiogenesis induced by mCRP/Notch-3/Fc combination while blocking Notch signalling by gamma-secretase inhibitor (DAPT) partially inhibited mCRP/Notch-3/Fc-induced angiogenesis. Using a BAEC vascular smooth muscle cell co-culture sprouting angiogenesis assay and transmission electron microscopy, we showed that activation of both mCRP and Notch-3 signalling induced the formation of thicker sprouts which were shown later by Western blotting to be associated with an up-regulation of N-cadherin expression and a down-regulation of VE-cadherin expression. Thus, mCRP combined with Notch-3 activator promote angiogenesis through the PI3K/Akt pathway and their therapeutic combination has potential to promote and stabilize vessel formation whilst reducing the risk of haemorrhage from unstable plaques. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Valsartan ameliorates podocyte loss in diabetic mice through the Notch pathway.

    PubMed

    Gao, Feng; Yao, Min; Cao, Yanping; Liu, Shuxia; Liu, Qingjuan; Duan, Huijun

    2016-05-01

    The Notch pathway is known to be linked to diabetic nephropathy (DN); however, its underlying mechanism was poorly understood. In the present study, we examined the effect of Valsartan, an angiotensin II type 1 receptor antagonist, on the Notch pathway and podocyte loss in DN. Diabetes was induced in mice by an intraperitoneal injection of streptozotocin and and this was followed by treatment with Valsartan. Levels of blood glucose, kidney weight and body weight, as well as proteinuria were measured. Samples of the kidneys were also histologically examined. The relative levels of Jagged1, Notch1, Notch intracellular domain 1 (NICD1), Hes family BHLH transcription factor 1 (Hes1) and Hes-related family BHLH transcription factor with YRPW motif 1 expression (Hey1) in the glomeruli were determined by immunohistochemical analysis, western blot analysis and RT-qPCR. The B-Cell CLL/Lymphoma 2 (Bcl-2) and p53 pathways were examined by western blot analysis. Apoptosis and detachment of podocytes from the glomerular basement membrane were examined using a TUNEL assay, flow cytometric analysis and ELISA. The number of podocytes was quantified by measuring Wilms tumor-1 (WT-1) staining. We noted that the expression of Jagged1, Notch1, NICD1, Hes1 and Hey1 was increased in a time-dependent manner in the glomeruli of mice with streptozotocin (STZ)-induced diabetes. Moreover, in diabetic mice, Valsartan significantly reduced kidney weight and proteinuria, and mitigated the pathogenic processes in the kidneys. Valsartan also inhibited the activation of Notch, Bcl-2 and p53 pathways and ameliorated podocyte loss in the glomeruli of mice with STZ-induced diabetes. Taken together, these findings indicated that Valsartan exerted a beneficial effect on reducing podocyte loss, which is associated with inhibition of Notch pathway activation in the glomeruli of diabetic mice.

  5. Inhibition of tumor angiogenesis and tumor growth by the DSL domain of human Delta-like 1 targeted to vascular endothelial cells.

    PubMed

    Zhao, Xing-Cheng; Dou, Guo-Rui; Wang, Li; Liang, Liang; Tian, Deng-Mei; Cao, Xiu-Li; Qin, Hong-Yan; Wang, Chun-Mei; Zhang, Ping; Han, Hua

    2013-07-01

    The growth of solid tumors depends on neovascularization. Several therapies targeting tumor angiogenesis have been developed. However, poor response in some tumors and emerging resistance necessitate further investigations of new drug targets. Notch signal pathway plays a pivotal role in vascular development and tumor angiogenesis. Either blockade or forced activation of this pathway can inhibit angiogenesis. As blocking Notch pathway results in the formation of vascular neoplasm, activation of Notch pathway to prevent tumor angiogenesis might be an alternative choice. However, an in vivo deliverable reagent with highly efficient Notch-activating capacity has not been developed. Here, we generated a polypeptide, hD1R, which consists of the Delta-Serrate-Lag-2 fragment of the human Notch ligand Delta-like 1 and an arginine-glycine-aspartate (RGD) motif targeting endothelial cells (ECs). We showed that hD1R could bind to ECs specifically through its RGD motif and effectively triggered Notch signaling in ECs. We demonstrated both in vitro and in vivo that hD1R inhibited angiogenic sprouting and EC proliferation. In tumor-bearing mice, the injection of hD1R effectively repressed tumor growth, most likely through increasing tumor hypoxia and tissue necrosis. The amount and width of vessels reduced remarkably in tumors of mice treated with hD1R. Moreover, vessels in tumors of mice treated with hD1R recruited more NG2(+) perivascular cells and were better perfused. Combined application of hD1R and chemotherapy with cisplatin and teniposide revealed that these two treatments had additive antitumor effects. Our study provided a new strategy for antiangiogenic tumor therapy.

  6. K-RasG12D–induced T-cell lymphoblastic lymphoma/leukemias harbor Notch1 mutations and are sensitive to γ-secretase inhibitors

    PubMed Central

    Cornejo, Melanie G.; Scholl, Claudia; Liu, Jianing; Leeman, Dena S.; Haydu, J. Erika; Fröhling, Stefan; Lee, Benjamin H.; Gilliland, D. Gary

    2008-01-01

    To study the impact of oncogenic K-Ras on T-cell leukemia/lymphoma development and progression, we made use of a conditional K-RasG12D murine knockin model, in which oncogenic K-Ras is expressed from its endogenous promoter. Transplantation of whole bone marrow cells that express oncogenic K-Ras into wild-type recipient mice resulted in a highly penetrant, aggressive T-cell leukemia/lymphoma. The lymphoblasts were composed of a CD4/CD8 double-positive population that aberrantly expressed CD44. Thymi of primary donor mice showed reduced cellularity, and immunophenotypic analysis demonstrated a block in differentiation at the double-negative 1 stage. With progression of disease, approximately 50% of mice acquired Notch1 mutations within the PEST domain. Of note, primary lymphoblasts were hypersensitive to γ-secretase inhibitor treatment, which is known to impair Notch signaling. This inhibition was Notch-specific as assessed by down-regulation of Notch1 target genes and intracellular cleaved Notch. We also observed that the oncogenic K-Ras-induced T-cell disease was responsive to rapamycin and inhibitors of the RAS/MAPK pathway. These data indicate that patients with T-cell leukemia with K-Ras mutations may benefit from therapies that target the NOTCH pathway alone or in combination with inhibition of the PI3K/AKT/MTOR and RAS/MAPK pathways. PMID:18663146

  7. Myeloid Notch1 deficiency activates the RhoA/ROCK pathway and aggravates hepatocellular damage in mouse ischemic livers.

    PubMed

    Lu, Ling; Yue, Shi; Jiang, Longfeng; Li, Changyong; Zhu, Qiang; Ke, Michael; Lu, Hao; Wang, Xuehao; Busuttil, Ronald W; Ying, Qi-Long; Kupiec-Weglinski, Jerzy W; Ke, Bibo

    2018-03-01

    Notch signaling plays an emerging role in the regulation of immune cell development and function during inflammatory response. Activation of the ras homolog gene family member A/Rho-associated protein kinase (ROCK) pathway promotes leukocyte accumulation in tissue injury. However, it remains unknown whether Notch signaling regulates ras homolog gene family member A/ROCK-mediated immune responses in liver ischemia and reperfusion (IR) injury. This study investigated intracellular signaling pathways regulated by Notch receptors in the IR-stressed liver and in vitro. In a mouse model of IR-induced liver inflammatory injury, we found that mice with myeloid-specific Notch1 knockout showed aggravated hepatocellular damage, with increased serum alanine aminotransferase levels, hepatocellular apoptosis, macrophage/neutrophil trafficking, and proinflammatory mediators compared to Notch1-proficient controls. Unlike in the controls, myeloid Notch1 ablation diminished hairy and enhancer of split-1 (Hes1) and augmented c-Jun N-terminal kinase (JNK)/stress-activated protein kinase-associated protein 1 (JSAP1), JNK, ROCK1, and phosphatase and tensin homolog (PTEN) activation in ischemic livers. Disruption of JSAP1 in myeloid-specific Notch1 knockout livers improved hepatocellular function and reduced JNK, ROCK1, PTEN, and toll-like receptor 4 activation. Moreover, ROCK1 knockdown inhibited PTEN and promoted Akt, leading to depressed toll-like receptor 4. In parallel in vitro studies, transfection of lentivirus-expressing Notch1 intracellular domain promoted Hes1 and inhibited JSAP1 in lipopolysaccharide-stimulated bone marrow-derived macrophages. Hes1 deletion enhanced JSAP1/JNK activation, whereas clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9-mediated JSAP1 knockout diminished ROCK1/PTEN and toll-like receptor 4 signaling. Myeloid Notch1 deficiency activates the ras homolog gene family member A/ROCK pathway and exacerbates hepatocellular injury by inhibiting transcriptional repressor Hes1 and inducing scaffold protein JSAP1 in IR-triggered liver inflammation; our findings underscore the crucial role of the Notch-Hes1 axis as a novel regulator of innate immunity-mediated inflammation and imply the therapeutic potential for the management of organ IR injury in transplant recipients. (Hepatology 2018;67:1041-1055). © 2017 by the American Association for the Study of Liver Diseases.

  8. Portulaca oleracea extract can inhibit nodule formation of colon cancer stem cells by regulating gene expression of the Notch signal transduction pathway.

    PubMed

    Jin, Heiying; Chen, Li; Wang, Shuiming; Chao, Deng

    2017-07-01

    To investigate whether Portulaca oleracea extract affects tumor formation in colon cancer stem cells and its chemotherapy sensitivity. In addition, to analyze associated genetic changes within the Notch signal transduction pathway. Serum-free cultures of colon cancer cells (HT-29) and HT-29 cancer stem cells were treated with the chemotherapeutic drug 5-fluorouracil to assess sensitivity. Injections of the stem cells were also given to BALB/c mice to confirm tumor growth and note its characteristics. In addition, the effect of different concentrations of P. oleracea extract was tested on the growth of HT-29 colon cancer cells and HT-29 cancer stem cells, as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. The effects of P. oleracea extract on the expression of β-catenin, Notch1, and Notch2 in the HT-29 cells were studied using reverse transcription polymerase chain reaction and Western blotting. The tumor volume of the HT29 cells was two times larger than that of HT29 cancer stem cells. Treatment with P. oleracea extract inhibited the proliferation of both HT-29 cancer cells and HT-29 cancer stem cells at doses from 0.07 to 2.25 µg/mL. Apoptosis of HT-29 cancer cells and HT-29 cancer stem cells was assessed by flow cytometry; it was enhanced by the addition of P. oleracea extract. Finally, treatment with P. oleracea extract significantly downregulated the expression of the Notch1 and β-catenin genes in both cell types. The results of this study show that P. oleracea extract inhibits the growth of colon cancer stem cells in a dose-dependent manner. Furthermore, it inhibits the expression of the Notch1 and β-catenin genes. Taken together, this suggests that it may elicit its effects through regulatory and target genes that mediate the Notch signal transduction pathway.

  9. Oncogenic NOTCH1 control of MYC and PI3K: challenges and opportunities for anti-NOTCH1 therapy in T-ALL

    PubMed Central

    Palomero, Teresa; Ferrando, Adolfo

    2008-01-01

    The identification of activating mutations in NOTCH1 in the majority of T-cell acute lymphoblastic leukemias and lymphomas (T-ALL) has brought much interest in inhibiting NOTCH1 signaling as therapeutic target in this disease. Small molecule inhibitors of the γ-secretase complex, which mediates a critical proteolytic cleavage required for NOTCH1 activation, hold the promise of becoming an effective molecular therapy against relapsed and refractory T-ALL. Recent progress in the elucidation of the transcriptional regulatory networks downstream of oncogenic NOTCH1 has uncovered a central role of NOTCH1 signaling in promoting leukemic cell growth and revealed an intricate circuitry that connects NOTCH1 signaling with MYC and the PI3K-AKT signaling pathway. The identification of the downstream effector pathways controlled by NOTCH1 should pave the way for the rational design of anti-NOTCH1 therapies for the treatment of T-ALL. PMID:18765521

  10. A Notch-dependent transcriptional hierarchy promotes mesenchymal transdifferentiation in the cardiac cushion.

    PubMed

    Chang, Alex C Y; Garside, Victoria C; Fournier, Michele; Smrz, Justin; Vrljicak, Pavle; Umlandt, Patricia; Fuller, Megan; Robertson, Gordon; Zhao, Yongjun; Tam, Angela; Jones, Steven J M; Marra, Marco A; Hoodless, Pamela A; Karsan, Aly

    2014-07-01

    Valvuloseptal defects are the most common congenital heart defects. Notch signaling-induced endothelial-to-mesenchymal transition (EMT) in the atrioventricular canal (AVC) cushions at murine embryonic day (E)9.5 is a required step during early valve development. Insights to the transcriptional network that is activated in endocardial cells (EC) during EMT and how these pathways direct valve maturation are lacking. We show that at E11.5, AVC-EC retain the ability to undergo Notch-dependent EMT when explanted on collagen. EC-Notch inhibition at E10.5 blocks expression of known mesenchymal genes in E11.5 AVC-EC. To understand the genetic network and AVC development downstream of Notch signaling beyond E9.5, we constructed Tag-Seq libraries corresponding to different cell types of the E11.5 AVC and atrium in wild-type mice and in EC-Notch inhibited mice. We identified 1,400 potential Notch targets in the AVC-EC, of which 124 are transcription factors (TF). From the 124 TFs, we constructed a transcriptional hierarchy and identify 10 upstream TFs within the network. We validated 4 of the upstream TFs as Notch targets that are enriched in AVC-EC. Functionally, we show these 4 TFs regulate EMT in AVC explant assays. These novel signaling pathways downstream of Notch are potentially relevant to valve development. © 2014 Wiley Periodicals, Inc.

  11. Acetylation-Dependent Regulation of Notch Signaling in Macrophages by SIRT1 Affects Sepsis Development

    PubMed Central

    Bai, Xiaozhi; He, Ting; Liu, Yang; Zhang, Julei; Li, Xiaoqiang; Shi, Jihong; Wang, Kejia; Han, Fu; Zhang, Wei; Zhang, Yijie; Cai, Weixia; Hu, Dahai

    2018-01-01

    SIRT1 is reported to participate in macrophage differentiation and affect sepsis, and Notch signaling is widely reported to influence inflammation and macrophage activation. However, the specific mechanisms through which SIRT1 regulates sepsis and the relationship between SIRT1 and Notch signaling remain poorly elucidated. In this study, we found that SIRT1 levels were decreased in sepsis both in vitro and in vivo and that SIRT1 regulation of Notch signaling affected inflammation. In lipopolysaccharide (LPS)-induced sepsis, the levels of Notch signaling molecules, including Notch1, Notch2, Hes1, and intracellular domain of Notch (NICD), were increased. However, NICD could be deacetylated by SIRT1, and this led to the suppression of Notch signaling. Notably, in macrophages from myeloid-specific RBP-J−/− mice, in which Notch signaling is inhibited, pro-inflammatory cytokines were expressed at lower levels than in macrophages from wild-type littermates and in RBP-J−/− macrophages, and the NF-κB pathway was also inhibited. Accordingly, in the case of RBP-J−/− mice, LPS-induced inflammation and mortality were lower than in wild-type mice. Our results indicate that SIRT1 inhibits Notch signaling through NICD deacetylation and thus ultimately alleviates sepsis. PMID:29867921

  12. Inhibition of gamma-secretase in Notch1 signaling pathway as a novel treatment for ovarian cancer.

    PubMed

    Feng, Zhaoyi; Xu, Wandong; Zhang, Chenguang; Liu, Mengran; Wen, Hongwu

    2017-01-31

    Epithelial ovarian cancer (EOC) is the leading cause of death for gynecological cancer. Most patients are not diagnosed until the cancer is at an advanced stage with poor prognosis. Notch1 signaling pathway plays an oncogenic role in EOC. There have been few studies on enzymatic activity of γ-secretase and the mechanism of how γ-secretase inhibitor works on cancer cell. Here, we show that Jagged1 and NICD were highly expressed in ovarian carcinoma. The expressions of Notch1, Jagged1 and NICD in Notch1 pathway did not correlate with outcome in ovarian cancer. The enzymatic activity of γ-secretase in ovarian cancer cell lines SKOV3, CAOV3 and ES2 is significantly higher than in normal ovarian epithelial cell line T29. DAPT (a γ-secretase inhibitor) reduced the enzymatic activity of γ-secretase, inhibited the proliferation, and increased the apoptosis in ovarian cancer cell lines. Hence, γ-secretase inhibitor may become a highly promising novel therapeutic strategy against ovarian cancer in the field of precision medicine.

  13. MicroRNA-449a Inhibition Protects H9C2 Cells Against Hypoxia/Reoxygenation-Induced Injury by Targeting the Notch-1 Signaling Pathway.

    PubMed

    Cheng, Jing; Wu, Qianfu; Lv, Rong; Huang, Li; Xu, Banglong; Wang, Xianbao; Chen, Aihua; He, Fei

    2018-05-07

    The present study aimed to detect the expression of miR-449a and investigate the effect of miR-449a on cell injury in cardiomyocytes subjected to hypoxia/ reoxygenation (H/R) and its underlying mechanisms. The expression of miR-449a was determined using reverse transcription-polymerase chain reaction in both neonatal rat ventricular myocytes and H9C2 cells. For gain-of-function and loss-of-function studies, H9C2 cells were transfected with either miR-449a mimics or miR-449a inhibitor. The target gene of miR-449a was confirmed by a dual-luciferase reporter assay. Apoptosis was analyzed by both flow cytometry using Annexin V and propidium iodide and transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL). Necrosis was confirmed by the detection of lactate dehydrogenase release. The cell viability was measured using the methylthiotetrazole method. The protein levels of Notch-1, Notch-1 intracellular domain, hairy and enhancer of split-1 (Hes-1), and apoptosis-related genes were measured by Western blot analysis. MiR-449a was significantly upregulated in both neonatal rat ventricular myocytes and H9C2 cells subjected to H/R. However, H/R-induced cell apoptosis and necrosis were markedly reduced by miR-449a inhibition. By targeting Notch-1, miR-449a regulated the Notch-1/ Hes-1 signaling pathway. The blockade of the Notch signaling pathway partly abolished the protective effect of miR-449a suppression against H/R injury, whereas the overexpression of Notch-1 intracellular domain partly reversed the effect of miR-449a overexpression on H/R-induced cell injury. The present study suggested that miR-449a inhibition protected H9C2 cells against H/R-induced cell injury by targeting the Notch-1 signaling pathway, providing a novel insight into the molecular basis of myocardial ischemia-reperfusion injury and a potential therapeutic target. © 2018 The Author(s). Published by S. Karger AG, Basel.

  14. Notch3 and Mef2c Proteins Are Mutually Antagonistic via Mkp1 Protein and miR-1/206 MicroRNAs in Differentiating Myoblasts*

    PubMed Central

    Gagan, Jeffrey; Dey, Bijan K.; Layer, Ryan; Yan, Zhen; Dutta, Anindya

    2012-01-01

    The Notch signaling pathway is a well known regulator of skeletal muscle stem cells known as satellite cells. Loss of Notch1 signaling leads to spontaneous myogenic differentiation. Notch1, normally expressed in satellite cells, is targeted for proteasomal degradation by Numb during differentiation. A homolog of Notch1, Notch3, is also expressed in these cells but is not inhibited by Numb. We find that Notch3 is paradoxically up-regulated during the early stages of differentiation by an enhancer that requires both MyoD and activated Notch1. Notch3 itself strongly inhibits the myogenic transcription factor Mef2c, most likely by increasing the p38 phosphatase Mkp1, which inhibits the Mef2c activator p38 MAP kinase. Active Notch3 decreases differentiation. Mef2c, however, induces microRNAs miR-1 and miR-206, which directly down-regulate Notch3 and allow differentiation to proceed. Thus, the myogenic differentiation-induced microRNAs miR-1 and -206 are important for differentiation at least partly because they turn off Notch3. We suggest that the transient expression of Notch3 early in differentiation generates a temporal lag between myoblast activation by MyoD and terminal differentiation into myotubes directed by Mef2c. PMID:23055528

  15. Serrate and Notch specify cell fates in the heart field by suppressing cardiomyogenesis.

    PubMed

    Rones, M S; McLaughlin, K A; Raffin, M; Mercola, M

    2000-09-01

    Notch signaling mediates numerous developmental cell fate decisions in organisms ranging from flies to humans, resulting in the generation of multiple cell types from equipotential precursors. In this paper, we present evidence that activation of Notch by its ligand Serrate apportions myogenic and non-myogenic cell fates within the early Xenopus heart field. The crescent-shaped field of heart mesoderm is specified initially as cardiomyogenic. While the ventral region of the field forms the myocardial tube, the dorsolateral portions lose myogenic potency and form the dorsal mesocardium and pericardial roof (Raffin, M., Leong, L. M., Rones, M. S., Sparrow, D., Mohun, T. and Mercola, M. (2000) Dev. Biol., 218, 326-340). The local interactions that establish or maintain the distinct myocardial and non-myocardial domains have never been described. Here we show that Xenopus Notch1 (Xotch) and Serrate1 are expressed in overlapping patterns in the early heart field. Conditional activation or inhibition of the Notch pathway with inducible dominant negative or active forms of the RBP-J/Suppressor of Hairless [Su(H)] transcription factor indicated that activation of Notch feeds back on Serrate1 gene expression to localize transcripts more dorsolaterally than those of Notch1, with overlap in the region of the developing mesocardium. Moreover, Notch pathway activation decreased myocardial gene expression and increased expression of a marker of the mesocardium and pericardial roof, whereas inhibition of Notch signaling had the opposite effect. Activation or inhibition of Notch also regulated contribution of individual cells to the myocardium. Importantly, expression of Nkx2. 5 and Gata4 remained largely unaffected, indicating that Notch signaling functions downstream of heart field specification. We conclude that Notch signaling through Su(H) suppresses cardiomyogenesis and that this activity is essential for the correct specification of myocardial and non-myocardial cell fates.

  16. Mangiferin induces apoptosis in human ovarian adenocarcinoma OVCAR3 cells via the regulation of Notch3

    PubMed Central

    Zou, Bingyu; Wang, Hailian; Liu, Yilong; Qi, Ping; Lei, Tiantian; Sun, Minghan; Wang, Yi

    2017-01-01

    Ovarian cancer is the most lethal gynecological malignancy in the world. Our previous studies showed that mangiferin, purified from plant source, possessed anti-neoplasm effect on human lung adenocarcinoma A549 cells. This study aimed to determine the apoptosis-inducing effect of mangiferin on human ovarian carcinoma OVCAR3 cells. By in vitro studies, we found mangiferin significantly inhibited viability of OVCAR3 cells, and remarkably increased the sensitivity of OVCAR3 cells to cisplatin. In addition, the activation of caspase-dependent apoptosis was observed in mangiferin treated ovarian cancer cells. Importantly, we observed an obviously downregulated Notch expression after mangiferin treatment, indicating the crucial role of Notch in mangiferin mediated apoptosis. In contrast, overexpression of Notch3 abrogated the apoptosis-inducing efficacy of mangiferin, further demonstrating that mangiferin induced apoptosis via Notch pathway. Furthermore, OVCAR3 cell xenograft models revealed that mangiferin treatment inhibited tumor growth and expanded survival of tumor xenograft mice. Based on these results, we concluded that mangiferin could significantly inhibit the proliferation and induce apoptosis in OVCAR3 cells. Our study also suggested the anti-neoplasm effect of mangiferin might be via the regulation of Notch3. Taken together, by targeting cell apoptosis pathways and enhancing the response to cisplatin treatment, mangiferin may represent a potential new drug for the treatment of human ovarian cancer. PMID:28714011

  17. Mangiferin induces apoptosis in human ovarian adenocarcinoma OVCAR3 cells via the regulation of Notch3.

    PubMed

    Zou, Bingyu; Wang, Hailian; Liu, Yilong; Qi, Ping; Lei, Tiantian; Sun, Minghan; Wang, Yi

    2017-09-01

    Ovarian cancer is the most lethal gynecological malignancy in the world. Our previous studies showed that mangiferin, purified from plant source, possessed anti-neoplasm effect on human lung adenocarcinoma A549 cells. This study aimed to determine the apoptosis-inducing effect of mangiferin on human ovarian carcinoma OVCAR3 cells. By in vitro studies, we found mangiferin significantly inhibited viability of OVCAR3 cells, and remarkably increased the sensitivity of OVCAR3 cells to cisplatin. In addition, the activation of caspase-dependent apoptosis was observed in mangiferin treated ovarian cancer cells. Importantly, we observed an obviously downregulated Notch expression after mangiferin treatment, indicating the crucial role of Notch in mangiferin mediated apoptosis. In contrast, overexpression of Notch3 abrogated the apoptosis-inducing efficacy of mangiferin, further demonstrating that mangiferin induced apoptosis via Notch pathway. Furthermore, OVCAR3 cell xenograft models revealed that mangiferin treatment inhibited tumor growth and expanded survival of tumor xenograft mice. Based on these results, we concluded that mangiferin could significantly inhibit the proliferation and induce apoptosis in OVCAR3 cells. Our study also suggested the anti-neoplasm effect of mangiferin might be via the regulation of Notch3. Taken together, by targeting cell apoptosis pathways and enhancing the response to cisplatin treatment, mangiferin may represent a potential new drug for the treatment of human ovarian cancer.

  18. Regulation of pancreatic stellate cell activation by Notch3.

    PubMed

    Song, Haiyan; Zhang, Yuxiang

    2018-01-05

    Activated pancreatic stellate cells (PaSCs) are the key cellular source of cancer-associated fibroblasts in the pancreatic stroma of patients with pancreatic ductal adenocarcinoma (PDAC), however, the activation mechanism of PaSCs is not yet known. The Notch signaling pathway, components of which are expressed in stromal cells, is involved in the fibrosis of several organs, including the lung and liver. In the current study, we investigated whether Notch signal transduction is involved in PaSC activation in PDAC. The expression of Notch signaling pathway components in human PDAC was examined via immunohistochemical staining and assessed in mouse PaSCs using RT-qPCR and western blotting. Notch3 expression in both PDAC stromal cells and activated mouse PaSCs was evaluated using immunofluorescence, RT-qPCR and western blotting. The impact of siRNA-mediated Notch3 knockdown on PaSC activation was detected with RT-qPCR and western blotting, and the impact on PaSC proliferation and migration was detected using CCK-8 assays and scratch experiments. The effect of conditioned medium from PaSCs activated with Notch3 siRNA on pancreatic cancer (LTPA) cells was also detected with CCK-8 assays and scratch experiments. The data were analyzed for statistical significance using Student's t-test. Notch3 was overexpressed in both human PDAC stromal cells and activated mouse PaSCs, and Notch3 knockdown with Notch3 siRNA decreased the proliferation and migration of mouse PaSCs. The levels of markers related to PaSC activation, such as α-smooth muscle actin (α-SMA), collagen I and fibronectin, decreased in response to Notch3 knockdown, indicating that Notch3 plays an important role in PaSC activation. Furthermore, we confirmed that inhibition of PaSC activation via Notch3 siRNA reduced the proliferation and migration of PaSC-induced mouse pancreatic cancer (LTPA) cells. Notch3 inhibition in PaSCs can inhibit the activation, proliferation and migration of PaSCs and reduce the PaSC-induced pro-tumorigenic effect. Therefore, Notch3 silencing in PaSCs is a potential novel therapeutic option for patients with PDAC.

  19. The CHAC1-inhibited Notch3 pathway is involved in temozolomide-induced glioma cytotoxicity.

    PubMed

    Chen, Peng-Hsu; Shen, Wan-Lin; Shih, Chwen-Ming; Ho, Kuo-Hao; Cheng, Chia-Hsiung; Lin, Cheng-Wei; Lee, Chin-Cheng; Liu, Ann-Jeng; Chen, Ku-Chung

    2017-04-01

    Glioblastoma multiforme (GBM) is the high-grade primary glioma in adults. Temozolomide (TMZ), an alkylating agent of the imidazotetrazine series, is a first-line chemotherapeutic drug for clinical therapy. However, the expense of TMZ therapy and increasing drug resistance to TMZ decreases its therapeutic effects. Therefore, our aim was to investigate the detailed molecular mechanisms of TMZ-mediated cytotoxicity to enhance the efficacy of TMZ in clinical GBM therapy. First, TMZ-mediated gene expression profiles and networks in U87-MG cells were identified by transcriptome microarray and bioinformatic analyses. Cation transport regulator-like protein 1 (CHAC1) was the most highly TMZ-upregulated gene. Overexpression and knockdown of CHAC1 expression significantly influenced TMZ-mediated cell viability, apoptosis, caspase-3 activation, and poly(ADP ribose) polymerase (PARP) degradation. The c-Jun N-terminal kinase (JNK)1/c-JUN pathway was identified to participate in TMZ-upregulated CHAC1 expression via transcriptional control. Furthermore, CHAC1 levels were significantly decreased in GBM cell lines, TCGA array data, and tumor tissues. Overexpression of CHAC1 enhanced glioma apoptotic death via caspase-3/9 activation, PARP degradation, autophagy formation, reactive oxygen species generation, increased intracellular calcium, and loss of the mitochondria membrane potential. Finally, we also identified that TMZ significantly reduced Notch3 levels, which are upregulated in gliomas. TMZ also induced CHAC1 to bind to the Notch3 protein and inhibit Notch3 activation, resulting in attenuation of Notch3-mediated downstream signaling pathways. These results emphasize that CHAC1-inhibited Notch3 signaling can influence TMZ-mediated cytotoxicity. Our findings may provide novel therapeutic strategies for future glioblastoma therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Apelin13/APJ promotes proliferation of colon carcinoma by activating Notch3 signaling pathway.

    PubMed

    Chen, Tong; Liu, Ning; Xu, Guang-Meng; Liu, Tong-Jun; Liu, Ying; Zhou, Yan; Huo, Si-Bo; Zhang, Kai

    2017-11-24

    The link between Apelin (APL)/APL receptor (APJ) and Jagged (JAG)/Notch signaling pathways in colorectal cancer (CRC) has been poorly investigated. APL/APJ system, a potent angiogenic factor, is up-regulated in a variety of cancers. It contributes to tumor angiogenesis, and correlates with progression of malignancy. JAG/Notch signaling also contributes to progression, proliferation and metastasis of multiple cancers, including CRC. Here we tested the hypothesis that APL/APJ system promotes CRC proliferation by up-regulating Notch3, thus allowing further binding of JAG1 to Notch3. We used a variety of methods including Western blot, RT-qPCR, gene silencing, ELISA, immunofluorescence staining, to investigate the interaction between APL/APJ system and Notch3 signaling pathway in both surgically-resected specimens and CRC cell line LS180. We show that the expression of APL13, APJ, and Notch3 is elevated in CRC. We further demonstrate that APL13 can be secreted into culture media of LS180 cells, suggesting the existence of autocrine loop in CRC. Moreover, we found that APL13 stimulated expression of Notch3. Finally, we found that inhibition of either APJ or Notch3 prevents proliferation of LS180 cells. Our results suggest that APL13/APJ and JAG1/Notch3 signaling pathways are linked in CRC. These findings provide a new direction to the efforts targeting effective therapeutic and management approaches in the treatment of CRC.

  1. Androgens Up-regulate Transcription of the Notch Inhibitor Numb in C2C12 Myoblasts via Wnt/β-Catenin Signaling to T Cell Factor Elements in the Numb Promoter*

    PubMed Central

    Liu, Xin-Hua; Wu, Yong; Yao, Shen; Levine, Alice C.; Kirschenbaum, Alexander; Collier, Lauren; Bauman, William A.; Cardozo, Christopher P.

    2013-01-01

    Androgen signaling via the androgen receptor is a key pathway that contributes to development, cell fate decisions, and differentiation, including that of myogenic progenitors. Androgens and synthetic steroids have well established anabolic actions on skeletal muscle. Wnt and Notch signaling pathways are also essential to myogenic cell fate decisions during development and tissue repair. However, the interactions among these pathways are largely unknown. Androgenic regulation of Wnt signaling has been reported. Nandrolone, an anabolic steroid, has been shown to inhibit Notch signaling and up-regulate Numb, a Notch inhibitor. To elucidate the mechanisms of interaction between nandrolone and Wnt/Notch signaling, we investigated the effects of nandrolone on Numb expression and Wnt signaling and determined the roles of Wnt signaling in nandrolone-induced Numb expression in C2C12 myoblasts. Nandrolone increased Numb mRNA and protein levels and T cell factor (Tcf) transcriptional activity via inhibition of glycogen synthase kinase 3β. Up-regulation of Numb expression by nandrolone was blocked by the Wnt inhibitors, sFRP1 and DKK1, whereas Wnt3a increased Numb mRNA and protein expression. In addition, we observed that the proximal promoter of the Numb gene had functional Tcf binding elements to which β-catenin was recruited in a manner enhanced by both nandrolone and Wnt3a. Moreover, site-directed mutagenesis indicated that the Tcf binding sites in the Numb promoter are required for the nandrolone-induced Numb transcriptional activation in this cell line. These results reveal a novel molecular mechanism underlying up-regulation of Numb transcription with a critical role for increased canonical Wnt signaling. In addition, the data identify Numb as a novel target gene of the Wnt signaling pathway by which Wnts would be able to inhibit Notch signaling. PMID:23649620

  2. Notch1 Signaling Sensitizes Tumor Necrosis Factor-related Apoptosis-inducing Ligand-induced Apoptosis in Human Hepatocellular Carcinoma Cells by Inhibiting Akt/Hdm2-mediated p53 Degradation and Up-regulating p53-dependent DR5 Expression*

    PubMed Central

    Wang, Chunmei; Qi, Runzi; Li, Nan; Wang, Zhengxin; An, Huazhang; Zhang, Qinghua; Yu, Yizhi; Cao, Xuetao

    2009-01-01

    Notch signaling plays a critical role in regulating cell proliferation, differentiation, and apoptosis. Our previous study showed that overexpression of Notch1 could inhibit human hepatocellular carcinoma (HCC) cell growth by arresting the cell cycle and inducing apoptosis. HCC cells are resistant to apoptotic induction by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), so new therapeutic approaches have been explored to sensitize HCC cells to TRAIL-induced apoptosis. We are wondering whether and how Notch1 signaling can enhance the sensitivity of HCC cells to TRAIL-induced apoptosis. In this study, we found that overexpression of ICN, the constitutive activated form of Notch1, up-regulated p53 protein expression in HCC cells by inhibiting proteasome degradation. p53 up-regulation was further observed in human primary hepatocellular carcinoma cells after activation of Notch signaling. Inhibition of the Akt/Hdm2 pathway by Notch1 signaling was responsible for the suppression of p53 proteasomal degradation, thus contributing to the Notch1 signaling-mediated up-regulation of p53 expression. Accordingly, Notch1 signaling could make HCC cells more sensitive to TRAIL-induced apoptosis, whereas Notch1 signaling lost the synergistic promotion of TRAIL-induced apoptosis in p53-silenced HepG2 HCC cells and p53-defective Hep3B HCC cells. The data suggest that enhancement of TRAIL-induced apoptosis by Notch1 signaling is dependent upon p53 up-regulation. Furthermore, Notch1 signaling could enhance DR5 expression in a p53-dependent manner. Taken together, Notch1 signaling sensitizes TRAIL-induced apoptosis in HCC cells by inhibiting Akt/Hdm2-mediated p53 degradation and up-regulating p53-dependent DR5 expression. Thus, our results suggest that activation of Notch1 signaling may be a promising approach to improve the therapeutic efficacy of TRAIL-resistant HCC. PMID:19376776

  3. Notch signaling mediates granulocyte-macrophage colony-stimulating factor priming-induced transendothelial migration of human eosinophils.

    PubMed

    Liu, L Y; Wang, H; Xenakis, J J; Spencer, L A

    2015-07-01

    Priming with cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances eosinophil migration and exacerbates the excessive accumulation of eosinophils within the bronchial mucosa of asthmatics. However, mechanisms that drive GM-CSF priming are incompletely understood. Notch signaling is an evolutionarily conserved pathway that regulates cellular processes, including migration, by integrating exogenous and cell-intrinsic cues. This study investigates the hypothesis that the priming-induced enhanced migration of human eosinophils requires the Notch signaling pathway. Using pan Notch inhibitors and newly developed human antibodies that specifically neutralize Notch receptor 1 activation, we investigated a role for Notch signaling in GM-CSF-primed transmigration of human blood eosinophils in vitro and in the airway accumulation of mouse eosinophils in vivo. Notch receptor 1 was constitutively active in freshly isolated human blood eosinophils, and inhibition of Notch signaling or specific blockade of Notch receptor 1 activation during GM-CSF priming impaired priming-enhanced eosinophil transendothelial migration in vitro. Inclusion of Notch signaling inhibitors during priming was associated with diminished ERK phosphorylation, and ERK-MAPK activation was required for GM-CSF priming-induced transmigration. In vivo in mice, eosinophil accumulation within allergic airways was impaired following systemic treatment with Notch inhibitor, or adoptive transfer of eosinophils treated ex vivo with Notch inhibitor. These data identify Notch signaling as an intrinsic pathway central to GM-CSF priming-induced eosinophil tissue migration. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Notch Inhibitor PF-03084014 Inhibits Hepatocellular Carcinoma Growth and Metastasis via Suppression of Cancer Stemness due to Reduced Activation of Notch1-Stat3.

    PubMed

    Wu, Chuan Xing; Xu, Aimin; Zhang, Cathy C; Olson, Peter; Chen, Lin; Lee, Terence K; Cheung, Tan To; Lo, Chung Mau; Wang, Xiao Qi

    2017-08-01

    Aberrant activation of the Notch signaling pathway is implicated in many solid tumors, including hepatocellular carcinoma, indicating a potential use of Notch inhibitors for treatment. In this study, we investigated the antitumor and antimetastasis efficacy of the novel Notch inhibitor (γ-secretase inhibitor) PF-03084014 in hepatocellular carcinoma. Hepatocellular carcinoma spherical cells (stem-like cancer cells), a sphere-derived orthotopic tumor model and one patient-derived xenograft (PDX) model were used in our experiment. We demonstrated that PF-03084014 inhibited the self-renewal and proliferation of cancer stem cells. PF-03084014 reduced the hepatocellular carcinoma sphere-derived orthotopic tumor and blocked the hepatocellular carcinoma tumor liver to lung metastasis. We further tested the PF-03084014 in PDX models and confirmed the inhibition tumor growth effect. In addition, a low dose of PF-03084014 induced hepatocellular carcinoma sphere differentiation, resulting in chemosensitization. Antitumor activity was associated with PF-03084014-induced suppression of Notch1 activity, decreased Stat3 activation and phosphorylation of the Akt signaling pathway, and reduced epithelial-mesenchymal transition. These are the key contributors to the maintenance of cancer stemness and the promotion of cancer metastasis. Moreover, the Notch-Stat3 association was implicated in the clinical hepatocellular carcinoma prognosis. Collectively, PF-03084014 revealed antitumor and antimetastatic effects in hepatocellular carcinoma, providing evidence for the potential use of gamma-secretase inhibitors as a therapeutic option for the treatment of hepatocellular carcinoma. Mol Cancer Ther; 16(8); 1531-43. ©2017 AACR . ©2017 American Association for Cancer Research.

  5. Notch Signaling in Postnatal Pituitary Expansion: Proliferation, Progenitors, and Cell Specification

    PubMed Central

    Nantie, Leah B.; Himes, Ashley D.; Getz, Dan R.

    2014-01-01

    Mutations in PROP1 account for up to half of the cases of combined pituitary hormone deficiency that result from known causes. Despite this, few signaling molecules and pathways that influence PROP1 expression have been identified. Notch signaling has been linked to Prop1 expression, but the developmental periods during which Notch signaling influences Prop1 and overall pituitary development remain unclear. To test the requirement for Notch signaling in establishing the normal pituitary hormone milieu, we generated mice with early embryonic conditional loss of Notch2 (conditional knockout) and examined the consequences of chemical Notch inhibition during early postnatal pituitary maturation. We show that loss of Notch2 has little influence on early embryonic pituitary proliferation but is crucial for postnatal progenitor maintenance and proliferation. In addition, we show that Notch signaling is necessary embryonically and postnatally for Prop1 expression and robust Pit1 lineage hormone cell expansion, as well as repression of the corticotrope lineage. Taken together, our studies identify temporal and cell type–specific roles for Notch signaling and highlight the importance of this pathway throughout pituitary development. PMID:24673559

  6. DLL4 overexpression increases gastric cancer stem/progenitor cell self-renewal ability and correlates with poor clinical outcome via Notch-1 signaling pathway activation.

    PubMed

    Miao, Zhi-Feng; Xu, Hao; Xu, Hui-Mian; Wang, Zhen-Ning; Zhao, Ting-Ting; Song, Yong-Xi; Xu, Ying-Ying

    2017-01-01

    Gastric cancer is one of the most common malignant diseases, and poses a serious threat to the quality of human life. Gastric cancer stem/progenitor cells (GCSPCs) have critical effects on tumor formation, affecting specific features of self-renewal and differentiation and playing a critical role in metastasis. The Notch-1 pathway is crucially important to GCSPCs and is regulated by DLL4. In this study, DLL4 and Nestin levels were measured in 383 gastric cancer tissue samples by immunohistochemistry, and the clinico-pathological features of patients assessed. After DLL4 silencing in selected gastric cancer cell lines, the expression of GCSPC markers and colony formation ability were analyzed and the self-renewal and differentiation capacities of the cells were evaluated. The relationship between DLL4 levels and Notch-1 signaling pathway effector amounts was assessed via Western blotting and immunofluorescence. Finally, the tumor formation ability of the gastric cancer cells was evaluated with different levels of DLL4 and multiple cell densities in vivo. Our results indicate that DLL4 expression is associated with TNM stage and cancer metastasis, with high amounts of DLL4 leading to poor outcome. DLL4 silencing inhibited the self-renewal ability of GCSPCs and increased their multidifferentiation capacity, resulting in reduced GCSPC ratios. DLL4 knockdown also blocked the Notch-1 pathway, weakening invasion ability and resistance to 5-FU chemotherapy. In vivo, DLL4 silencing inhibited the tumor formation ability of GCSPCs. In conclusion, DLL4 affects GCSPC stemness, altering their pathological behavior. DLL4 silencing inhibits GCSPC metastatic potential both in vitro and in vivo by impeding Notch-1 signaling pathway activation, indicating that DLL4 may be a new potential therapeutic target. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  7. Notch pathway signaling in the skin antagonizes Merkel cell development.

    PubMed

    Logan, Gregory J; Wright, Margaret C; Kubicki, Adam C; Maricich, Stephen M

    2018-02-15

    Merkel cells are mechanosensitive skin cells derived from the epidermal lineage whose development requires expression of the basic helix-loop-helix transcription factor Atoh1. The genes and pathways involved in regulating Merkel cell development during embryogenesis are poorly understood. Notch pathway signaling antagonizes Atoh1 expression in many developing body regions, so we hypothesized that Notch signaling might inhibit Merkel cell development. We found that conditional, constitutive overexpression of the Notch intracellular domain (NICD) in mouse epidermis significantly decreased Merkel cell numbers in whisker follicles and touch domes of hairy skin. Conversely, conditional deletion of the obligate NICD binding partner RBPj in the epidermis significantly increased Merkel cell numbers in whisker follicles, led to the development of ectopic Merkel cells outside of touch domes in hairy skin epidermis, and altered the distribution of Merkel cells in touch domes. Deletion of the downstream Notch effector gene Hes1 also significantly increased Merkel cell numbers in whisker follicles. Together, these data demonstrate that Notch signaling regulates Merkel cell production and patterning. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. 3,6-dihydroxyflavone suppresses the epithelial-mesenchymal transition in breast cancer cells by inhibiting the Notch signaling pathway.

    PubMed

    Chen, Junli; Chang, Hui; Peng, Xiaoli; Gu, Yeyun; Yi, Long; Zhang, Qianyong; Zhu, Jundong; Mi, Mantian

    2016-06-27

    The epithelial to mesenchymal transition (EMT) is a critical developmental program in cancer stem cell (CSC) maintenance and in cancer metastasis. Here, our study found that 3,6-DHF could effectively inhibit EMT in BC cells in vitro and in vivo. 3,6-DHF effectively inhibits the formation and proliferation of BCSCs, and consequently reduces the tumor-initiating capacity of tumor cells in NOD/SCID mice. Optical in vivo imaging of cancer metastasis showed that 3,6-DHF administration suppresses the lung metastasis of BC cells in vivo. Further studies indicated that 3,6-DHF down-regulates Notch1, NICD, Hes-1 and c-Myc, consequently decreasing the formation of the functional transcriptional unit of NICD-CSL-MAML, causing Notch signaling inactivation in BC cells. Over-expression of Notch1 or inhibition of miR-34a significantly reduced the inhibitory effects of 3,6-DHF on EMT, CSCs, as well as cells migration and invasion in BC cells. These data indicated that 3,6-DHF effectively inhibits EMT and CSCs, as well as cells migration and invasion in BC cells, in which miR-34a-mediated Notch1 down-regulation plays a crucial role.

  9. Genetic deletion of Rnd3 in neural stem cells promotes proliferation via upregulation of Notch signaling.

    PubMed

    Dong, Huimin; Lin, Xi; Li, Yuntao; Hu, Ronghua; Xu, Yang; Guo, Xiaojie; La, Qiong; Wang, Shun; Fang, Congcong; Guo, Junli; Li, Qi; Mao, Shanping; Liu, Baohui

    2017-10-31

    Rnd3, a Rho GTPase, is involved in the inhibition of actin cytoskeleton dynamics through the Rho kinase-dependent signaling pathway. We previously demonstrated that mice with genetic deletion of Rnd3 developed a markedly larger brain compared with wild-type mice. Here, we demonstrate that Rnd3 knockout mice developed an enlarged subventricular zone, and we identify a novel role for Rnd3 as an inhibitor of Notch signaling in neural stem cells. Rnd3 deficiency, both in vivo and in vitro , resulted in increased levels of Notch intracellular domain protein. This led to enhanced Notch signaling and promotion of aberrant neural stem cell growth, thereby resulting in a larger subventricular zone and a markedly larger brain. Inhibition of Notch activity abrogated this aberrant neural stem cell growth.

  10. Evaluation of role of Notch3 signaling pathway in human lung cancer cells.

    PubMed

    Hassan, Wael Abdo; Yoshida, Ryoji; Kudoh, Shinji; Motooka, Yamato; Ito, Takaaki

    2016-05-01

    There is still a debate on the extent to which Notch3 signaling is involved in lung carcinogenesis and whether such function is dependent on cancer type or not. To evaluate Notch3 expression in different types of human lung cancer cells. Notch3 was detected in human lung cancer cell lines and in tissues. Then, small interfering RNA (siRNA) was used to down-regulate the expression of Notch3 in H69AR small cell lung carcinoma (SCLC) cells; two non-small cell lung carcinoma (NSCLC) cells; A549 adenocarcinoma (ADC); and H2170 squamous cell carcinoma (SCC). In addition, Notch3 intracellular domain (N3ICD) plasmid was transfected into H1688 human SCLC cells. We observed the effect of deregulating Notch3 signaling on the following cell properties: Notch-related proteins, cell morphology, adhesion, epithelial-mesenchymal transition (EMT), motility, proliferation and neuroendocrine (NE) features of SCLC. Notch3 is mainly expressed in NSCLC, and the expression of Notch1, Hes1 and Jagged1 is affected by Notch3. Notch3 has opposite functions in SCLC and NSCLC, being a tumor suppressor in the former and tumor promoting in the latter, in the context of cell adhesion, EMT and motility. Regarding cell proliferation, we found that inhibiting Notch3 in NSCLC decreases cell proliferation and induces apoptosis in NSCLC. Notch3 has no effect on cell proliferation or NE features of SCLC. Notch3 signaling in lung carcinoma is dependent on cell type. In SCLC, Notch3 behaves as a tumor suppressor pathway, while in NSCLC it acts as a tumor-promoting pathway.

  11. Notch signalling drives bone marrow stromal cell-mediated chemoresistance in acute myeloid leukemia

    PubMed Central

    Kamga, Paul Takam; Bassi, Giulio; Cassaro, Adriana; Midolo, Martina; Di Trapani, Mariano; Gatti, Alessandro; Carusone, Roberta; Resci, Federica; Perbellini, Omar; Gottardi, Michele; Bonifacio, Massimiliano; Kamdje, Armel Hervé Nwabo; Ambrosetti, Achille; Krampera, Mauro

    2016-01-01

    Both preclinical and clinical investigations suggest that Notch signalling is critical for the development of many cancers and for their response to chemotherapy. We previously showed that Notch inhibition abrogates stromal-induced chemoresistance in lymphoid neoplasms. However, the role of Notch in acute myeloid leukemia (AML) and its contribution to the crosstalk between leukemia cells and bone marrow stromal cells remain controversial. Thus, we evaluated the role of the Notch pathway in the proliferation, survival and chemoresistance of AML cells in co-culture with bone marrow mesenchymal stromal cells expanded from both healthy donors (hBM-MSCs) and AML patients (hBM-MSCs*). As compared to hBM-MSCs, hBM-MSCs* showed higher level of Notch1, Jagged1 as well as the main Notch target gene HES1. Notably, hBM-MSCs* induced expression and activation of Notch signalling in AML cells, supporting AML proliferation and being more efficientin inducing AML chemoresistance than hBM-MSCs*. Pharmacological inhibition of Notch using combinations of Notch receptor-blocking antibodies or gamma-secretase inhibitors (GSIs), in presence of chemotherapeutic agents, significant lowered the supportive effect of hBM-MSCs and hBM-MSCs* towards AML cells, by activating apoptotic cascade and reducing protein level of STAT3, AKT and NF-κB. These results suggest that Notch signalling inhibition, by overcoming the stromal-mediated promotion of chemoresistance,may represent a potential therapeutic targetnot only for lymphoid neoplasms, but also for AML. PMID:26967055

  12. Notch3 Ameliorates Cardiac Fibrosis After Myocardial Infarction by Inhibiting the TGF-β1/Smad3 Pathway.

    PubMed

    Zhang, Mingming; Pan, Xietian; Zou, Qian; Xia, Yuesheng; Chen, Jiangwei; Hao, Qimeng; Wang, Haichang; Sun, Dongdong

    2016-10-01

    Notch3 and TGF-β1 signaling play a key role in the pathogenesis and progression of chronic cardiovascular disease. However, whether Notch3 protects against myocardial infarction (MI) and the underlying mechanisms remains unknown. C57BL/6 mice were randomized to be treated with Notch3 siRNA (siNotch3) or lentivirus carrying Notch3 cDNA (Notch3) before coronary artery ligation. Four weeks after constructing MI model, cardiac function and fibrosis were compared between groups. The cardiac fibroblast cells (CFs) were isolated from newborn C57BL/6 mice (1-3 days old) and transfected with lentivirus carrying Notch3 cDNA. TGF-β1 (5 ng/ml), a well-known pro-fibrotic factor, was administered 72 h after Notch3 cDNA administration in CFs. The related proteins of fibrosis such as a-smooth muscle actin (a-SMA), Type I collagen, metalloprotease (MMP)-9 and the tissue inhibitor of metalloproteinases (TIMP)-2 were examined by western blot analysis. Notch3 cDNA treatment attenuated cardiac damage and inhibited fibrosis in mice with MI. Meanwhile, Notch3 siRNA administration aggravated cardiac function damage and markedly enhanced cardiac fibrosis in mice with MI. Overexpression of Notch3 inhibited TGF-β1-induced fibroblast-myofibroblast transition of mouse cardiac fibroblast cells, as evidenced by down-regulating a-SMA and Type I collagen expression. Notch3 cDNA treatment also increased MMP-9 expression and decreased TIMP-2 expression in the TGF-β1-stimulated cells. This study indicates that Notch3 is an important protective factor for cardiac fibrosis in a MI model, and the protective effect of Notch3 is attributable to its action on TGF-β1/Smad3 signaling.

  13. Thiocoraline alters neuroendocrine phenotype and activates the Notch pathway in MTC-TT cell line

    PubMed Central

    Tesfazghi, Sara; Eide, Jacob; Dammalapati, Ajitha; Korlesky, Colin; Wyche, Thomas P; Bugni, Tim S; Chen, Herbert; Jaskula-Sztul, Renata

    2013-01-01

    Medullary thyroid cancer (MTC) is an aggressive neuroendocrine tumor (NET). Previous research has shown that activation of Notch signaling has a tumor suppressor role in NETs. The potential therapeutic effect of thiocoraline on the activation of the Notch pathway in an MTC cell line (TT) was investigated. Thiocoraline was isolated from a marine bacterium Verrucosispora sp. MTT assay (3-[4, 5-dimethylthiazole-2-yl]-2, 5-diphenyltetrazolium bromide) was used to determine the IC50 value and to measure cell proliferation. Western blot revealed the expression of Notch isoforms, NET, and cell cycle markers. Cell cycle progression was validated by flow cytometry. The mRNA expression of Notch isoforms and downstream targets were measured using real-time PCR. The IC50 value for thiocoraline treatment in TT cells was determined to be 7.6 nmol/L. Thiocoraline treatment decreased cell proliferation in a dose- and time-dependent manner. The mechanism of growth inhibition was found to be cell cycle arrest in G1 phase. Thiocoraline activated the Notch pathway as demonstrated by the dose-dependent increase in mRNA and protein expression of Notch isoforms. Furthermore, treatment with thiocoraline resulted in changes in the expression of downstream targets of the Notch pathway (HES1, HES2, HES6, HEY1, and HEY2) and reduced expression of NET markers, CgA, and ASCL1. Thiocoraline is a potent Notch pathway activator and an inhibitor of MTC-TT cell proliferation at low nanomolar concentrations. These results provide exciting evidence for the use of thiocoraline as a potential treatment for intractable MTC. Thiocoraline is a potent Notch pathway activator and an inhibitor of medullary thyroid cancer cell line (MTC-TT) cell proliferation at low nanomolar concentrations. These results provide evidence for the use of thiocoraline as a potential treatment for intractable MTC. PMID:24403239

  14. Diallyl trisulfide inhibits proliferation, invasion and angiogenesis of osteosarcoma cells by switching on suppressor microRNAs and inactivating of Notch-1 signaling.

    PubMed

    Li, Yonggang; Zhang, Jingru; Zhang, Lei; Si, Meng; Yin, Han; Li, Jianmin

    2013-07-01

    Notch signaling pathway plays critical roles in human cancers, including osteosarcoma, suggesting that the discovery of specific agents targeting Notch would be extremely valuable for osteosarcoma. Our previous studies have shown that diallyl trisulfide (DATS) inhibits proliferation of osteosarcoma cells by triggering cell cycle arrest and apoptosis in vitro. However, the underlying mechanism is still unclear. In this study, we found that DATS suppressed cell survival, wound-healing capacity, invasion and angiogenesis in osteosarcoma cells. These effects were associated with decreased expression of Notch-1 and its downstream genes, such as vascular endothelial growth factor and matrix metalloproteinases, as well as increased expression of a panel of tumor-suppressive microRNAs (miRNAs), including miR-34a, miR-143, miR-145 and miR-200b/c that are typically lost in osteosarcoma. We also found that reexpression of miR-34a and miR-200b by transfection led to reduced expression of Notch-1, resulting in the inhibition of osteosarcoma cell proliferation, invasion and angiogenesis. These results clearly suggest that DATS inhibited osteosarcoma growth and aggressiveness via a novel mechanism targeting a Notch-miRNA regulatory circuit. Our data provide the first evidence that the downregulation of Notch-1 and reexpression of miRNAs by DATS may be an effective approach for the treatment of osteosarcoma.

  15. All-trans-retinoic Acid Modulates the Plasticity and Inhibits the Motility of Breast Cancer Cells: ROLE OF NOTCH1 AND TRANSFORMING GROWTH FACTOR (TGFβ).

    PubMed

    Zanetti, Adriana; Affatato, Roberta; Centritto, Floriana; Fratelli, Maddalena; Kurosaki, Mami; Barzago, Maria Monica; Bolis, Marco; Terao, Mineko; Garattini, Enrico; Paroni, Gabriela

    2015-07-17

    All-trans-retinoic acid (ATRA) is a natural compound proposed for the treatment/chemoprevention of breast cancer. Increasing evidence indicates that aberrant regulation of epithelial-to-mesenchymal transition (EMT) is a determinant of the cancer cell invasive and metastatic behavior. The effects of ATRA on EMT are largely unknown. In HER2-positive SKBR3 and UACC812 cells, showing co-amplification of the ERBB2 and RARA genes, ATRA activates a RARα-dependent epithelial differentiation program. In SKBR3 cells, this causes the formation/reorganization of adherens and tight junctions. Epithelial differentiation and augmented cell-cell contacts underlie the anti-migratory action exerted by the retinoid in cells exposed to the EMT-inducing factors EGF and heregulin-β1. Down-regulation of NOTCH1, an emerging EMT modulator, is involved in the inhibition of motility by ATRA. Indeed, the retinoid blocks NOTCH1 up-regulation by EGF and/or heregulin-β1. Pharmacological inhibition of γ-secretase and NOTCH1 processing also abrogates SKBR3 cell migration. Stimulation of TGFβ contributes to the anti-migratory effect of ATRA. The retinoid switches TGFβ from an EMT-inducing and pro-migratory determinant to an anti-migratory mediator. Inhibition of the NOTCH1 pathway not only plays a role in the anti-migratory action of ATRA; it is relevant also for the anti-proliferative activity of the retinoid in HCC1599 breast cancer cells, which are addicted to NOTCH1 for growth/viability. This effect is enhanced by the combination of ATRA and the γ-secretase inhibitor N-(N-(3,5-difluorophenacetyl)-l-alanyl)-S-phenylglycine t-butyl ester, supporting the concept that the two compounds act at the transcriptional and post-translational levels along the NOTCH1 pathway. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Emodin suppresses TGF-β1-induced epithelial-mesenchymal transition in alveolar epithelial cells through Notch signaling pathway.

    PubMed

    Gao, Rundi; Chen, Ruilin; Cao, Yu; Wang, Yuan; Song, Kang; Zhang, Ya; Yang, Junchao

    2017-03-01

    Pulmonary fibrosis is characterized by the destruction of lung tissue architecture and the formation of fibrous foci, currently has no satisfactory treatment. Emodin is a component of Chinese herb that has been reported to be medicament on pancreatic fibrosis and liver fibrosis. However, its role in pulmonary fibrosis has not been established yet. In the present study, we investigated the hypothesis that Emodin plays an inhibitory role in TGF-β1 induced epithelial-mesenchymal transition (EMT) of alveolar epithelial cell, and Emodin exerts its effect through the Notch signaling pathway. Emodin inhibits the proliferation of Rat alveolar type II epithelial cells RLE-6TN in a concentration-dependent manner; reduces the expression of Collagen I, α-SMA and Vimentin, promotes the expression of E-cadherin. Moreover, Emodin could regulate the expression patterns of the Notch signaling pathway-related factors and reduce the Notch-1 nucleus translocation. Knockdown of Notch-1 enhances the inhibitory effect of Emodin on TGF-β1-induced EMT in RLE-6TN cells. In conclusion, the data of the present study suggests that Emodin suppresses TGF-β1-induced EMT in alveolar epithelial cells through Notch signaling pathway and shows the potential to be effective in the treatment of pulmonary fibrosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. [IL-23 promotes invasion of esophageal squamous cell carcinoma cells by activating DLL4/Notch1 signaling pathway].

    PubMed

    Li, Wei; Zhou, Yuepeng; Su, Yuting; Ouyang, Yibo; Xie, Xiaodong; Wu, Yingying; Mao, Chaoming; Chen, Deyu

    2015-06-01

    To investigate the role of interlukin-23 (IL-23) in the invasion of human esophageal squamous cell carcinoma (ESCC) cells and the related mechanism. IL-23 expression in tumor and adjacent tissues from 10 ESCC patients were detected by immunohistochemistry. Real-time fluorescent PCR was used to examine the expressions of Notch1 and Foxn4 mRNAs in different concentration IL-23-treated TE-1 cells. After Notch pathway was blocked with γ-secretase inhibitor DAPT, expressions of Notch intracellular domain (NICD), Delta-like 4 (DLL4), hairy enhancer of split 1 (Hes1), matrix metalloproteinase 9 (MMP-9) in IL-23-treated TE-1 cells were measured by Western blotting. And the migration of IL-23-treated TE-1 cells was studied by TranswellTM migration assay. Compared with adjacent tissues, IL-23 was highly expressed in ESCC tissues. IL-23 treatment up-regulated significantly the expressions of NICD, DLL4, Hes1 and MMP-9 in TE-1 cells. The blockade of Notch1 pathway inhibited the expressions induced by IL-23. Migration assay revealed that IL-23 treatment significantly enhanced the migration of TE-1 cells. IL-23 could promote migration of human ESCC cells by activating DLL4/Notch1 signaling pathway.

  18. A Novel Notch-YAP Circuit Drives Stemness and Tumorigenesis in Embryonal Rhabdomyosarcoma.

    PubMed

    Slemmons, Katherine K; Crose, Lisa E S; Riedel, Stefan; Sushnitha, Manuela; Belyea, Brian; Linardic, Corinne M

    2017-12-01

    Rhabdomyosarcoma (RMS), a cancer characterized by skeletal muscle features, is the most common soft-tissue sarcoma of childhood. While low- and intermediate-risk groups have seen improved outcomes, high-risk patients still face a 5-year survival rate of <30%, a statistic that has not changed in over 40 years. Understanding the biologic underpinnings of RMS is critical. The developmental pathways of Notch and YAP have been identified as potent but independent oncogenic signals that support the embryonal variant of RMS (eRMS). Here, the cross-talk between these pathways and the impact on eRMS tumorigenesis is reported. Using human eRMS cells grown as three-dimensional (3D) rhabdospheres, which enriches in stem cells, it was found that Notch signaling transcriptionally upregulates YAP1 gene expression and YAP activity. Reciprocally, YAP transcriptionally upregulates the Notch ligand genes JAG1 and DLL1 and the core Notch transcription factor RBPJ This bidirectional circuit boosts expression of key stem cell genes, including SOX2 , which is functionally required for eRMS spheres. Silencing this circuit for therapeutic purposes may be challenging, because the inhibition of one node (e.g., pharmacologic Notch blockade) can be rescued by upregulation of another (constitutive YAP expression). Instead, dual inhibition of Notch and YAP is necessary. Finally, supporting the existence of this circuit beyond a model system, nuclear Notch and YAP protein expression are correlated in human eRMS tumors, and YAP suppression in vivo decreases Notch signaling and SOX2 expression. Implications: This study identifies a novel oncogenic signaling circuit driving eRMS stemness and tumorigenesis, and provides evidence and rationale for combination therapies co-targeting Notch and YAP. Mol Cancer Res; 15(12); 1777-91. ©2017 AACR . ©2017 American Association for Cancer Research.

  19. mTOR-Notch3 signaling mediates pulmonary hypertension in hypoxia-exposed neonatal rats independent of changes in autophagy.

    PubMed

    Ivanovska, Julijana; Shah, Sparsh; Wong, Mathew J; Kantores, Crystal; Jain, Amish; Post, Martin; Yeganeh, Behzad; Jankov, Robert P

    2017-11-01

    Mammalian target of rapamycin (mTOR) is a pivotal regulator of cell proliferation, survival, and autophagy. Autophagy is increased in adult experimental chronic pulmonary hypertension (PHT), but its contributory role to pulmonary vascular disease remains uncertain and has yet to be explored in the neonatal animal. Notch is a major pro-proliferative pathway activated by mTOR. A direct relationship between autophagy and Notch signaling has not been previously explored. Our aim was to examine changes in mTOR-, Notch-, and autophagy-related pathways and the therapeutic effects of autophagy modulators in experimental chronic neonatal PHT secondary to chronic hypoxia. Rat pups were exposed to normoxia or hypoxia (13% O 2 ) from postnatal days 1-21, while receiving treatment with temsirolimus (mTOR inhibitor), DAPT (Notch inhibitor), or chloroquine (inhibitor of autophagic flux). Exposure to hypoxia up-regulated autophagy and Notch3 signaling markers in lung, pulmonary artery (PA), and PA-derived smooth muscle cells (SMCs). Temsirolimus prevented chronic PHT and attenuated PA and SMC signaling secondary to hypoxia. These effects were replicated by DAPT. mTOR or Notch inhibition also down-regulated smooth muscle content of platelet-derived growth factor β-receptor, a known contributor to vascular remodeling. In contrast, chloroquine had no modifying effects on markers of chronic PHT. Knockdown of Beclin-1 in SMCs had no effect on hypoxia-stimulated Notch3 signaling. mTOR-Notch3 signaling plays a critical role in experimental chronic neonatal PHT. Inhibition of autophagy did not suppress Notch signaling and had no effect on markers of chronic PHT. © 2017 Wiley Periodicals, Inc.

  20. Human myostatin negatively regulates human myoblast growth and differentiation

    PubMed Central

    McFarlane, Craig; Hui, Gu Zi; Amanda, Wong Zhi Wei; Lau, Hiu Yeung; Lokireddy, Sudarsanareddy; XiaoJia, Ge; Mouly, Vincent; Butler-Browne, Gillian; Gluckman, Peter D.; Sharma, Mridula

    2011-01-01

    Myostatin, a member of the transforming growth factor-β superfamily, has been implicated in the potent negative regulation of myogenesis in murine models. However, little is known about the mechanism(s) through which human myostatin negatively regulates human skeletal muscle growth. Using human primary myoblasts and recombinant human myostatin protein, we show here that myostatin blocks human myoblast proliferation by regulating cell cycle progression through targeted upregulation of p21. We further show that myostatin regulates myogenic differentiation through the inhibition of key myogenic regulatory factors including MyoD, via canonical Smad signaling. In addition, we have for the first time demonstrated the capability of myostatin to regulate the Notch signaling pathway during inhibition of human myoblast differentiation. Treatment with myostatin results in the upregulation of Hes1, Hes5, and Hey1 expression during differentiation; moreover, when we interfere with Notch signaling, through treatment with the γ-secretase inhibitor L-685,458, we find enhanced myotube formation despite the presence of excess myostatin. Therefore, blockade of the Notch pathway relieves myostatin repression of differentiation, and myostatin upregulates Notch downstream target genes. Immunoprecipitation studies demonstrate that myostatin treatment of myoblasts results in enhanced association of Notch1-intracellular domain with Smad3, providing an additional mechanism through which myostatin targets and represses the activity of the myogenic regulatory factor MyoD. On the basis of these results, we suggest that myostatin function and mechanism of action are very well conserved between species, and that myostatin regulation of postnatal myogenesis involves interactions with numerous downstream signaling mediators, including the Notch pathway. PMID:21508334

  1. Human myostatin negatively regulates human myoblast growth and differentiation.

    PubMed

    McFarlane, Craig; Hui, Gu Zi; Amanda, Wong Zhi Wei; Lau, Hiu Yeung; Lokireddy, Sudarsanareddy; Xiaojia, Ge; Mouly, Vincent; Butler-Browne, Gillian; Gluckman, Peter D; Sharma, Mridula; Kambadur, Ravi

    2011-07-01

    Myostatin, a member of the transforming growth factor-β superfamily, has been implicated in the potent negative regulation of myogenesis in murine models. However, little is known about the mechanism(s) through which human myostatin negatively regulates human skeletal muscle growth. Using human primary myoblasts and recombinant human myostatin protein, we show here that myostatin blocks human myoblast proliferation by regulating cell cycle progression through targeted upregulation of p21. We further show that myostatin regulates myogenic differentiation through the inhibition of key myogenic regulatory factors including MyoD, via canonical Smad signaling. In addition, we have for the first time demonstrated the capability of myostatin to regulate the Notch signaling pathway during inhibition of human myoblast differentiation. Treatment with myostatin results in the upregulation of Hes1, Hes5, and Hey1 expression during differentiation; moreover, when we interfere with Notch signaling, through treatment with the γ-secretase inhibitor L-685,458, we find enhanced myotube formation despite the presence of excess myostatin. Therefore, blockade of the Notch pathway relieves myostatin repression of differentiation, and myostatin upregulates Notch downstream target genes. Immunoprecipitation studies demonstrate that myostatin treatment of myoblasts results in enhanced association of Notch1-intracellular domain with Smad3, providing an additional mechanism through which myostatin targets and represses the activity of the myogenic regulatory factor MyoD. On the basis of these results, we suggest that myostatin function and mechanism of action are very well conserved between species, and that myostatin regulation of postnatal myogenesis involves interactions with numerous downstream signaling mediators, including the Notch pathway.

  2. Rho/ROCK-dependent inhibition of 3T3-L1 adipogenesis by G-protein-deamidating dermonecrotic toxins: differential regulation of Notch1, Pref1/Dlk1, and β-catenin signaling

    PubMed Central

    Bannai, Yuka; Aminova, Leila R.; Faulkner, Melinda J.; Ho, Mengfei; Wilson, Brenda A.

    2012-01-01

    The dermonecrotic toxins from Pasteurella multocida (PMT), Bordetella (DNT), Escherichia coli (CNF1-3), and Yersinia (CNFY) modulate their G-protein targets through deamidation and/or transglutamination of an active site Gln residue, which results in activation of the G protein and its cognate downstream signaling pathways. Whereas DNT and the CNFs act on small Rho GTPases, PMT acts on the α subunit of heterotrimeric Gq, Gi, and G12/13 proteins. We previously demonstrated that PMT potently blocks adipogenesis and adipocyte differentiation in a calcineurin-independent manner through downregulation of Notch1 and stabilization of β-catenin and Pref1/Dlk1, key proteins in signaling pathways strongly linked to cell fate decisions, including fat and bone development. Here, we report that similar to PMT, DNT, and CNF1 completely block adipogenesis and adipocyte differentiation by preventing upregulation of adipocyte markers, PPARγ and C/EBPα, while stabilizing the expression of Pref1/Dlk1 and β-catenin. We show that the Rho/ROCK inhibitor Y-27632 prevented or reversed these toxin-mediated effects, strongly supporting a role for Rho/ROCK signaling in dermonecrotic toxin-mediated inhibition of adipogenesis and adipocyte differentiation. Toxin treatment was also accompanied by downregulation of Notch1 expression, although this inhibition was independent of Rho/ROCK signaling. We further show that PMT-mediated downregulation of Notch1 expression occurs primarily through G12/13 signaling. Our results reveal new details of the pathways involved in dermonecrotic toxin action on adipocyte differentiation, and the role of Rho/ROCK signaling in mediating toxin effects on Wnt/β-catenin and Notch1 signaling, and in particular the role of Gq and G12/13 in mediating PMT effects on Rho/ROCK and Notch1 signaling. PMID:22919671

  3. Multiple Notch signaling events control Drosophila CNS midline neurogenesis, gliogenesis and neuronal identity

    PubMed Central

    Wheeler, Scott R.; Stagg, Stephanie B.; Crews, Stephen T.

    2009-01-01

    The study of how transcriptional control and cell signaling influence neurons and glia to acquire their differentiated properties is fundamental to understanding CNS development and function. The Drosophila CNS midline cells are an excellent system for studying these issues because they consist of a small population of diverse cells with well-defined gene expression profiles. In this paper, the origins and differentiation of midline neurons and glia were analyzed. Midline precursor (MP) cells each divide once giving rise to two neurons; here, we use a combination of single-cell gene expression mapping and time-lapse imaging to identify individual MPs, their locations, movements and stereotyped patterns of division. The role of Notch signaling was investigated by analyzing 37 midline-expressed genes in Notch pathway mutant and misexpression embryos. Notch signaling had opposing functions: it inhibited neurogenesis in MP1,3,4 and promoted neurogenesis in MP5,6. Notch signaling also promoted midline glial and median neuroblast cell fate. This latter result suggests that the median neuroblast resembles brain neuroblasts that require Notch signaling, rather than nerve cord neuroblasts, the formation of which is inhibited by Notch signaling. Asymmetric MP daughter cell fates also depend on Notch signaling. One member of each pair of MP3–6 daughter cells was responsive to Notch signaling. By contrast, the other daughter cell asymmetrically acquired Numb, which inhibited Notch signaling, leading to a different fate choice. In summary, this paper describes the formation and division of MPs and multiple roles for Notch signaling in midline cell development, providing a foundation for comprehensive molecular analyses. PMID:18701546

  4. Wnt and Notch signaling pathway involved in wound healing by targeting c-Myc and Hes1 separately.

    PubMed

    Shi, Yan; Shu, Bin; Yang, Ronghua; Xu, Yingbin; Xing, Bangrong; Liu, Jian; Chen, Lei; Qi, Shaohai; Liu, Xusheng; Wang, Peng; Tang, Jinming; Xie, Julin

    2015-06-16

    Wnt and Notch signaling pathways are critically involved in relative cell fate decisions within the development of cutaneous tissues. Moreover, several studies identified the above two pathways as having a significant role during wound healing. However, their biological effects during cutaneous tissues repair are unclear. We employed a self-controlled model (Sprague-Dawley rats with full-thickness skin wounds) to observe the action and effect of Wnt/β-catenin and Notch signalings in vivo. The quality of wound repair relevant to the gain/loss-of-function Wnt/β-catenin and Notch activation was estimated by hematoxylin-and-eosin and Masson staining. Immunofluorescence analysis and Western blot analysis were used to elucidate the underlying mechanism of the regulation of Wnt and Notch signaling pathways in wound healing. Meanwhile, epidermal stem cells (ESCs) were cultured in keratinocyte serum-free medium with Jaggedl or in DAPT (N-[(3,5-difluorophenyl)acetyl]-L-alanyl-2-phenyl]glycine-1,1-dimethylethyl) to investigate whether the interruption of Notch signaling contributes to the expression of Wnt/β-catenin signaling. The results showed that in vivo the gain-of-function Wnt/β-catenin and Notch activation extended the ability to promote wound closure. We further determined that activation or inhibition of Wnt signaling and Notch signaling can affect the proliferation of ESCs, the differentiation and migration of keratinocytes, and follicle regeneration by targeting c-Myc and Hes1, which ultimately lead to enhanced or delayed wound healing. Furthermore, Western blot analysis suggested that the two pathways might interact in vivo and in vitro. These results suggest that Wnt and Notch signalings play important roles in cutaneous repair by targeting c-Myc and Hes1 separately. What's more, interaction between the above two pathways might act as a vital role in regulation of wound healing.

  5. The adaptor SASH1 acts through NOTCH1 and its inhibitor DLK1 in a 3D model of lumenogenesis involving CEACAM1.

    PubMed

    Stubblefield, Kandis; Chean, Jennifer; Nguyen, Tung; Chen, Charng-Jui; Shively, John E

    2017-10-15

    CEACAM1 transfection into breast cancer cells restores lumen formation in a 3D culture model. Among the top up-regulated genes that were associated with restoration of lumen formation, the adaptor protein SASH1 was identified. Furthermore, SASH1 was shown to be critical for lumen formation by RNAi inhibition. Upon analyzing the gene array from CEACAM1/MCF7 cells treated with SASH1 RNAi, DLK1, an inhibitor of NOTCH1 signaling, was found to be down-regulated to the same extent as SASH1. Subsequent treatment of CEACAM1/MCF7 cells with RNAi to DLK1 also inhibited lumen formation, supporting its association with SASH1. In agreement with the role of DLK1 as a NOTCH1 inhibitor, NOTCH1, as well as its regulated genes HES1 and HEY1, were down-regulated in CEACAM1/MCF7 cells by the action of DLK1 RNAi, and up-regulated by SASH1 RNAi. When CEACAM1/MCF7 cells were treated with a γ-secretase inhibitor known to inhibit NOTCH signaling, lumen formation was inhibited. We conclude that restoration of lumen formation by CEACAM1 regulates the NOTCH1 signaling pathway via the adaptor protein SASH1 and the NOTCH1 inhibitor DLK1. These data suggest that the putative involvement of NOTCH1 as a tumor-promoting gene in breast cancer may depend on its lack of regulation in cancer, whereas its involvement in normal lumen formation requires activation of its expression, and subsequently, inhibition of its signaling. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Bone morphogenetic protein and Notch signalling crosstalk in poor-prognosis, mesenchymal-subtype colorectal cancer.

    PubMed

    Irshad, Shazia; Bansal, Mukesh; Guarnieri, Paolo; Davis, Hayley; Al Haj Zen, Ayman; Baran, Brygida; Pinna, Claudia Maria Assunta; Rahman, Haseeb; Biswas, Sujata; Bardella, Chiara; Jeffery, Rosemary; Wang, Lai Mun; East, James Edward; Tomlinson, Ian; Lewis, Annabelle; Leedham, Simon John

    2017-06-01

    The functional role of bone morphogenetic protein (BMP) signalling in colorectal cancer (CRC) is poorly defined, with contradictory results in cancer cell line models reflecting the inherent difficulties of assessing a signalling pathway that is context-dependent and subject to genetic constraints. By assessing the transcriptional response of a diploid human colonic epithelial cell line to BMP ligand stimulation, we generated a prognostic BMP signalling signature, which was applied to multiple CRC datasets to investigate BMP heterogeneity across CRC molecular subtypes. We linked BMP and Notch signalling pathway activity and function in human colonic epithelial cells, and normal and neoplastic tissue. BMP induced Notch through a γ-secretase-independent interaction, regulated by the SMAD proteins. In homeostasis, BMP/Notch co-localization was restricted to cells at the top of the intestinal crypt, with more widespread interaction in some human CRC samples. BMP signalling was downregulated in the majority of CRCs, but was conserved specifically in mesenchymal-subtype tumours, where it interacts with Notch to induce an epithelial-mesenchymal transition (EMT) phenotype. In intestinal homeostasis, BMP-Notch pathway crosstalk is restricted to differentiating cells through stringent pathway segregation. Conserved BMP activity and loss of signalling stringency in mesenchymal-subtype tumours promotes a synergistic BMP-Notch interaction, and this correlates with poor patient prognosis. BMP signalling heterogeneity across CRC subtypes and cell lines can account for previous experimental contradictions. Crosstalk between the BMP and Notch pathways will render mesenchymal-subtype CRC insensitive to γ-secretase inhibition unless BMP activation is concomitantly addressed. © 2017 The Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

  7. Constitutive NOTCH3 Signaling Promotes the Growth of Basal Breast Cancers.

    PubMed

    Choy, Lisa; Hagenbeek, Thijs J; Solon, Margaret; French, Dorothy; Finkle, David; Shelton, Amy; Venook, Rayna; Brauer, Matthew J; Siebel, Christian W

    2017-03-15

    Notch ligands signal through one of four receptors on neighboring cells to mediate cell-cell communication and control cell fate, proliferation, and survival. Although aberrant Notch activation has been implicated in numerous malignancies, including breast cancer, the importance of individual receptors in distinct breast cancer subtypes and the mechanisms of receptor activation remain unclear. Using a novel antibody to detect active NOTCH3, we report here that NOTCH3 signals constitutively in a panel of basal breast cancer cell lines and in more than one third of basal tumors. Selective inhibition of individual ligands revealed that this signal does not require canonical ligand induction. A NOTCH3 antagonist antibody inhibited growth of basal lines, whereas a NOTCH3 agonist antibody enhanced the transformed phenotype in vitro and in tumor xenografts. Transcriptomic analyses generated a Notch gene signature that included Notch pathway components, the oncogene c-Myc , and the mammary stem cell regulator Id4 This signature drove clustering of breast cancer cell lines and tumors into the common subtypes and correlated with the basal classification. Our results highlight an unexpected ligand-independent induction mechanism and suggest that constitutive NOTCH3 signaling can drive an oncogenic program in a subset of basal breast cancers. Cancer Res; 77(6); 1439-52. ©2017 AACR . ©2017 American Association for Cancer Research.

  8. Targeting Notch pathway induces growth inhibition and differentiation of neuroblastoma cells.

    PubMed

    Ferrari-Toninelli, Giulia; Bonini, Sara Anna; Uberti, Daniela; Buizza, Laura; Bettinsoli, Paola; Poliani, Pietro Luigi; Facchetti, Fabio; Memo, Maurizio

    2010-12-01

    High-risk neuroblastoma is a severe pediatric tumor characterized by poor prognosis. Understanding the molecular mechanisms involved in tumor development and progression is strategic for the improvement of pharmacological therapies. Notch was recently proposed as a pharmacological target for the therapy of several cancers and is emerging as a new neuroblastoma-related molecular pathway. However, the precise role played by Notch in this cancer remains to be studied extensively. Here, we show that Notch activation by the Jagged1 ligand enhances the proliferation of neuroblastoma cells, and we propose the possible use of Notch-blocking γ-secretase inhibitors (GSIs) in neuroblastoma therapy. Two different GSIs, Compound E and DAPT, were tested alone or in combination with 13-cis retinoic acid (RA) on neuroblastoma cell lines. SH-SY5Y and IMR-32 cells were chosen as paradigms of lower and higher malignancy, respectively. Used alone, GSIs induced complete cell growth arrest, promoted neuronal differentiation, and significantly reduced cell motility. The combination of GSIs and 13-cis RA resulted in the enhanced growth inhibition, differentiation, and migration of neuroblastoma cells. In summary, our data suggest that a combination of GSIs with 13-cis RA offers a therapeutic advantage over a single agent, indicating a potential novel therapy for neuroblastoma.

  9. Loss of Oncogenic Notch1 with Resistance to a PI3K Inhibitor in T Cell Leukaemia

    PubMed Central

    Dail, Monique; Wong, Jason; Lawrence, Jessica; O’Connor, Daniel; Nakitandwe, Joy; Chen, Shann-Ching; Xu, Jin; Lee, Leslie B; Akagi, Keiko; Li, Qing; Aster, Jon C.; Pear, Warren S.; Downing, James R; Sampath, Deepak; Shannon, Kevin

    2014-01-01

    Mutations that deregulate Notch1 and Ras/PI3 kinase/Akt signalling are prevalent in T lineage acute lymphoblastic leukaemia (T-ALL), and often coexist. The PI3 kinase inhibitor GDC-0941 was active against primary T-ALLs from wild-type and KrasG12D mice and addition of the MEK inhibitor PD0325901 increased efficacy. Mice invariably relapsed after treatment with drug resistant clones, most of which unexpectedly had reduced levels of activated Notch1 protein, down-regulated many Notch1 target genes, and exhibited cross-resistance to γ secretase inhibitors. Multiple resistant primary T-ALLs that emerged in vivo did not contain somatic Notch1 mutations present in the parental leukaemia. Importantly, resistant clones up-regulated PI3K signalling. Consistent with these data, inhibiting Notch1 activated the PI3K pathway, providing a likely mechanism for selection against oncogenic Notch1 signalling. These studies validate PI3K as a therapeutic target in T-ALL and raise the unexpected possibility that dual inhibition of PI3K and Notch1 signalling could facilitate drug resistance in T-ALL. PMID:25043004

  10. Loss of oncogenic Notch1 with resistance to a PI3K inhibitor in T-cell leukaemia.

    PubMed

    Dail, Monique; Wong, Jason; Lawrence, Jessica; O'Connor, Daniel; Nakitandwe, Joy; Chen, Shann-Ching; Xu, Jin; Lee, Leslie B; Akagi, Keiko; Li, Qing; Aster, Jon C; Pear, Warren S; Downing, James R; Sampath, Deepak; Shannon, Kevin

    2014-09-25

    Mutations that deregulate Notch1 and Ras/phosphoinositide 3 kinase (PI3K)/Akt signalling are prevalent in T-cell acute lymphoblastic leukaemia (T-ALL), and often coexist. Here we show that the PI3K inhibitor GDC-0941 is active against primary T-ALLs from wild-type and Kras(G12D) mice, and addition of the MEK inhibitor PD0325901 increases its efficacy. Mice invariably relapsed after treatment with drug-resistant clones, most of which unexpectedly had reduced levels of activated Notch1 protein, downregulated many Notch1 target genes, and exhibited cross-resistance to γ-secretase inhibitors. Multiple resistant primary T-ALLs that emerged in vivo did not contain somatic Notch1 mutations present in the parental leukaemia. Importantly, resistant clones upregulated PI3K signalling. Consistent with these data, inhibiting Notch1 activated the PI3K pathway, providing a likely mechanism for selection against oncogenic Notch1 signalling. These studies validate PI3K as a therapeutic target in T-ALL and raise the unexpected possibility that dual inhibition of PI3K and Notch1 signalling could promote drug resistance in T-ALL.

  11. The MSX1 homeobox transcription factor is a downstream target of PHOX2B and activates the Delta-Notch pathway in neuroblastoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Revet, Ingrid; Huizenga, Gerda; Chan, Alvin

    Neuroblastoma is an embryonal tumour of the peripheral sympathetic nervous system (SNS). One of the master regulator genes for peripheral SNS differentiation, the homeobox transcription factor PHOX2B, is mutated in familiar and sporadic neuroblastomas. Here we report that inducible expression of PHOX2B in the neuroblastoma cell line SJNB-8 down-regulates MSX1, a homeobox gene important for embryonic neural crest development. Inducible expression of MSX1 in SJNB-8 caused inhibition of both cell proliferation and colony formation in soft agar. Affymetrix micro-array and Northern blot analysis demonstrated that MSX1 strongly up-regulated the Delta-Notch pathway genes DLK1, NOTCH3, and HEY1. In addition, the proneuralmore » gene NEUROD1 was down-regulated. Western blot analysis showed that MSX1 induction caused cleavage of the NOTCH3 protein to its activated form, further confirming activation of the Delta-Notch pathway. These experiments describe for the first time regulation of the Delta-Notch pathway by MSX1, and connect these genes to the PHOX2B oncogene, indicative of a role in neuroblastoma biology. Affymetrix micro-array analysis of a neuroblastic tumour series consisting of neuroblastomas and the more benign ganglioneuromas showed that MSX1, NOTCH3 and HEY1 are more highly expressed in ganglioneuromas. This suggests a block in differentiation of these tumours at distinct developmental stages or lineages.« less

  12. FOXP3 expression is modulated by TGF-β1/NOTCH1 pathway in human melanoma

    PubMed Central

    Skarmoutsou, Eva; Bevelacqua, Valentina; D'Amico, Fabio; Russo, Angela; Spandidos, Demetrios A.; Scalisi, Aurora

    2018-01-01

    Forkhead box protein 3 (FOXP3) transcription factor is expressed by immune cells and several human cancers and is associated with tumor aggressiveness and unfavorable clinical outcomes. NOTCH and transforming growth factor-β (TGF-β) protumorigenic effects are mediated by FOXP3 expression in several cancer models; however, their interaction and role in melanoma is unknown. We investigated TGF-β-induced FOXP3 gene expression during NOTCH1 signaling inactivation. Primary (WM35) and metastatic melanoma (A375 and A2058) cell lines and normal melanocytes (NHEM) were used. FOXP3 subcellular distribution was evaluated by immuno cytochemical analysis. Gene expression levels were assessed by reverse transcription-quantitative polymerase chain reaction. Protein levels were assessed by western blot analysis. The γ-secretase inhibitor (GSI) was used for NOTCH1 inhibition and recombinant human (rh)TGF-β was used for melanoma cell stimulation. Cell proliferation and viability were respectively assessed by MTT and Trypan blue dye assays. FOXP3 mRNA and protein levels were progressively higher in WM35, A375 and A2058 cell lines compared to NHEM and their levels were further increased after stimulation with rh-TGF-β. TGF-β-mediated FOXP3 expression was mediated by NOTCH1 signaling. Inhibition of NOTCH1 with concomitant rh-TGF-β stimulation determined the reduction in gene expression and protein level of FOXP3. Finally, melanoma cell line proliferation and viability were reduced by NOTCH1 inhibition. The results show that nn increase in FOXP3 expression in metastatic melanoma cell lines is a potential marker of tumor aggressiveness and metastasis. NOTCH1 is a central mediator of TGF-β-mediated FOXP3 expression and NOTCH1 inhibition produces a significant reduction of melanoma cell proliferation and viability. PMID:29620159

  13. The clerodane diterpene casearin J induces apoptosis of T-ALL cells through SERCA inhibition, oxidative stress, and interference with Notch1 signaling

    PubMed Central

    De Ford, C; Heidersdorf, B; Haun, F; Murillo, R; Friedrich, T; Borner, C; Merfort, I

    2016-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy that preferentially affects children and adolescents. Over 50% of human T-ALLs possess activating mutations of Notch1. The clerodane diterpene casearin J (CJ) is a natural product that inhibits the sarcoendoplasmatic reticulum calcium ATPase (SERCA) pump and induces cell death in leukemia cells, but the molecular mechanism of cytotoxicity remains poorly understood. Here we show that owing to SERCA pump inhibition, CJ induces depletion of the endoplasmic reticulum calcium pools, oxidative stress, and apoptosis via the intrinsic signaling pathway. Moreover, Notch1 signaling is reduced in T-ALL cells with auto-activating mutations in the HD-domain of Notch1, but not in cells that do not depend on Notch1 signaling. CJ also provoked a slight activation of NF-κB, and consistent with this notion a combined treatment of CJ and the NF-κB inhibitor parthenolide (Pt) led to a remarkable synergistic cell death in T-ALL cells. Altogether, our data support the concept that inhibition of the SERCA pump may be a novel strategy for the treatment of T-ALL with HD-domain-mutant Notch1 receptors and that additional treatment with the NF-κB inhibitor parthenolide may have further therapeutic benefits. PMID:26821066

  14. Down-regulation of Notch signaling pathway reverses the Th1/Th2 imbalance in tuberculosis patients.

    PubMed

    Li, Qifeng; Zhang, Hui; Yu, Liang; Wu, Chao; Luo, Xinhui; Sun, He; Ding, Jianbing

    2018-01-01

    Th1/Th2 imbalance to Th2 is of significance in the peripheral immune responses in Tuberculosis (TB) development. However, the mechanisms for Th1/Th2 imbalance are still not well determined. Notch signaling pathway is involved in the peripheral T cell activation and effector cell differentiation. However, whether it affects Th1/Th2 imbalance in TB patients is still not known. Here, we used γ-secretase inhibitor (DAPT) to treat the peripheral blood mononuclear cells (PBMCs) from healthy people or individuals with latent or active TB infection in vitro, respectively. Then, the Th1/Th2 ratios were determined by flow cytometry, and cytokines of IFN-γ, IL-4, IL-10 in the culture supernatant were measured by CBA method. The Notch signal pathway associated proteins Hes1, GATA3 and T-bet were quantitated by real-time PCR or immunoblotting. Our results showed that DAPT effectively inhibited the protein level of Hes1. In TB patients, the Th2 ratio increased in the PBMCs, alone with the high expression of GATA3 and IL-4, resulting in the high ratios of Th2/Th1 and GATA3/T-bet in TB patients. However, Th2 cells ratio decreased after blocking the Notch signaling pathway by DAPT and the Th2/Th1 ratio in TB patients were DAPT dose-dependent, accompanied by the decrease of IL-4 and GATA3. But, its influence on Th1 ratio and Th1 related T-bet and IFN-γ levels were not significant. In conclusion, our results suggest that blocking Notch signaling by DAPT could inhibit Th2 responses and restore Th1/Th2 imbalance in TB patients. Copyright © 2017. Published by Elsevier B.V.

  15. Notch signaling regulates the responses of lipopolysaccharide-stimulated macrophages in the presence of immune complexes.

    PubMed

    Wongchana, Wipawee; Kongkavitoon, Pornrat; Tangtanatakul, Pattarin; Sittplangkoon, Chutamath; Butta, Patcharavadee; Chawalitpong, Supatta; Pattarakankul, Thitiporn; Osborne, Barbara A; Palaga, Tanapat

    2018-01-01

    Macrophages exhibit diverse effector phenotypes depending on the stimuli and their microenvironment. Classically activated macrophages are primed with interferon (IFN)γ and stimulated with pathogen-associated molecular patterns. They produce inflammatory mediators and inflammatory cytokines, such as IL-12. In the presence of immune complexes (ICs), activated macrophages have decreased IL-12 production and increased IL-10 production and presumably act as regulatory macrophages. Notch signaling has been shown to regulate the effector functions of classically activated macrophages. In this study, we investigated whether Notch signaling is active in lipopolysaccharide (LPS)-stimulated macrophages in the presence of ICs. LPS/IC stimulation increased the level of cleaved Notch1 in murine macrophages, while IC stimulation alone did not. Delta-like 4, but not Jagged1, was responsible for generating cleaved Notch1. The activation of Notch signaling by LPS/ICs depended upon NF-κB and MEK/Erk pathway activation. Macrophages with the targeted deletion of Rbpj, which encodes a DNA-binding protein central to canonical Notch signaling, produced significantly less IL-10 upon LPS/IC stimulation. A similar impact on IL-10 production was observed when Notch signaling was inhibited with a gamma-secretase inhibitor (GSI). Defects in NF-κB p50 nuclear localization were observed in GSI-treated macrophages and in Rbpj-/- macrophages, suggesting cross-regulation between the Notch and NF-κB pathways. Transcriptomic analysis revealed that Notch signaling regulates the transcription of genes involved in the cell cycle, macrophage activation, leukocyte migration and cytokine production in LPS/IC-stimulated macrophages. Taken together, these results suggest that the Notch signaling pathway plays an important role in regulating the functions of macrophages activated by LPS and ICs.

  16. Retinoic acid plays an evolutionarily conserved and biphasic role in pancreas development

    PubMed Central

    Huang, Wei; Wang, Guangliang; Delaspre, Fabien; Vitery, Maria del Carmen; Beer, Rebecca L.

    2015-01-01

    As the developing zebrafish pancreas matures, hormone-producing endocrine cells differentiate from pancreatic Notch-responsive cells (PNCs) that reside within the ducts. These new endocrine cells form small clusters known as secondary (2°) islets. We use the formation of 2° islets in the pancreatic tail of the larval zebrafish as a model of β-cell neogenesis. Pharmacological inhibition of Notch signaling leads to precocious endocrine differentiation and the early appearance of 2° islets in the tail of the pancreas. Following a chemical screen, we discovered that blocking the retinoic acid (RA)-signaling pathway also leads to the induction of 2° islets. Conversely, the addition of exogenous RA blocks the differentiation caused by Notch inhibition. In this report we characterize the interaction of these two pathways. We first verified that signaling via both RA and Notch ligands act together to regulate pancreatic progenitor differentiation. We produced a transgenic RA reporter, which demonstrated that PNCs directly respond to RA signaling through the canonical transcriptional pathway. Next, using a genetic lineage tracing approach, we demonstrated these progenitors produce endocrine cells following inhibition of RA signaling. Lastly, inhibition of RA signaling using a cell-type specific inducible cre/lox system revealed that RA signaling acts cell-autonomously in PNCs to regulate their differentiation. Importantly, the action of RA inhibition on endocrine formation is evolutionarily conserved, as shown by the differentiation of human embryonic stem cells in a model of human pancreas development. Together, these results revealed a biphasic function for RA in pancreatogenesis. As previously shown by others, RA initially plays an essential role during embryogenesis as it patterns the endoderm and specifies the pancreatic field. We reveal here that later in development RA is involved in negatively regulating the further differentiation of pancreatic progenitors and expands upon the developmental mechanisms by which this occurs. PMID:25127993

  17. NOTCH1 Inhibits Activation of ATM by Impairing the Formation of an ATM-FOXO3a-KAT5/Tip60 Complex.

    PubMed

    Adamowicz, Marek; Vermezovic, Jelena; d'Adda di Fagagna, Fabrizio

    2016-08-23

    The DNA damage response (DDR) signal transduction pathway is responsible for sensing DNA damage and further relaying this signal into the cell. ATM is an apical DDR kinase that orchestrates the activation and the recruitment of downstream DDR factors to induce cell-cycle arrest and repair. We have previously shown that NOTCH1 inhibits ATM activation upon DNA damage, but the underlying mechanism remains unclear. Here, we show that NOTCH1 does not impair ATM recruitment to DNA double-strand breaks (DSBs). Rather, NOTCH1 prevents binding of FOXO3a and KAT5/Tip60 to ATM through a mechanism in which NOTCH1 competes with FOXO3a for ATM binding. Lack of FOXO3a binding to ATM leads to the loss of KAT5/Tip60 association with ATM. Moreover, expression of NOTCH1 or depletion of ATM impairs the formation of the FOXO3a-KAT5/Tip60 protein complex. Finally, we show that pharmacological induction of FOXO3a nuclear localization sensitizes NOTCH1-driven cancers to DNA-damage-induced cell death. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Qingyihuaji Formula Inhibits Pancreatic Cancer and Prolongs Survival by Downregulating Hes-1 and Hey-1.

    PubMed

    Xu, Yanli; Xu, Shan; Cai, Yueqin; Liu, Luming

    2015-01-01

    The dire prognosis of pancreatic cancer has not markedly improved during past decades. The present study was carried out to explore the effect of Qingyihuaji formula (QYHJ) on inhibiting pancreatic cancer and prolonging survival in related Notch signaling pathway. Proliferation of pancreatic cancer cells (SW1990 and PANC-1) was detected by MTT assay at 24, 48, and 72 h with exposure to various concentrations (0.08-50 mg/mL) of QYHJ water extract. Pancreatic tumor models of nude mice were divided into three groups randomly (control, QYHJ, and gemcitabine). mRNA and protein expression of Notch target genes (Hes-1, Hey-1, Hey-2, and Hey-L) in dissected tumor tissue were detected. Results showed that proliferation of SW1990 cells and PANC-1 cells was inhibited by QYHJ water extract in a dose-dependent and time-dependent manner. QYHJ effectively inhibited tumor growth and prolonged survival time in nude mice. Expression of both Hes-1 and Hey-1 was decreased significantly in QYHJ group, suggesting that Hes-1 and Hey-1 in Notch signaling pathway might be potential targets for QYHJ treatment. This research could help explain the clinical effectiveness of QYHJ and may provide advanced pancreatic cancer patients with a new therapeutic option.

  19. Curcumin Induces Cell Death in Esophageal Cancer Cells through Modulating Notch Signaling

    PubMed Central

    Subramaniam, Dharmalingam; Ponnurangam, Sivapriya; Ramamoorthy, Prabhu; Standing, David; Battafarano, Richard J.; Anant, Shrikant; Sharma, Prateek

    2012-01-01

    Background Curcumin inhibits the growth of esophageal cancer cell lines; however, the mechanism of action is not well understood. It is becoming increasingly clear that aberrant activation of Notch signaling has been associated with the development of esophageal cancer. Here, we have determined that curcumin inhibits esophageal cancer growth via a mechanism mediated through the Notch signaling pathway. Methodology/Principal Findings In this study, we show that curcumin treatment resulted in a dose and time dependent inhibition of proliferation and colony formation in esophageal cancer cell lines. Furthermore, curcumin treatment induced apoptosis through caspase 3 activation, confirmed by an increase in the ratio of Bax to Bcl2. Cell cycle analysis demonstrated that curcumin treatment induced cell death and down regulated cyclin D1 levels. Curcumin treatment also resulted in reduced number and size of esophagospheres. Furthermore, curcumin treatment led to reduced Notch-1 activation, expression of Jagged-1 and its downstream target Hes-1. This reduction in Notch-1 activation was determined to be due to the down-regulation of critical components of the γ-secretase complex proteins such as Presenilin 1 and Nicastrin. The combination of a known γ-secretase inhibitor DAPT and curcumin further decreased proliferation and induced apoptosis in esophageal cancer cells. Finally, curcumin treatment down-regulate the expressions of Notch-1 specific microRNAs miR-21 and miR-34a, and upregulated tumor suppressor let-7a miRNA. Conclusion/Significance Curcumin is a potent inhibitor of esophageal cancer growth that targets the Notch-1 activating γ-secretase complex proteins. These data suggest that Notch signaling inhibition is a novel mechanism of action for curcumin during therapeutic intervention in esophageal cancers. PMID:22363450

  20. The Notch/Hes1 pathway sustains NF-κB activation through CYLD repression in T cell leukemia

    PubMed Central

    Espinosa, Lluis; Cathelin, Severine; D’Altri, Teresa; Trimarchi, Thomas; Statnikov, Alexander; Guiu, Jordi; Rodilla, Veronica; Inglés-Esteve, Julia; Nomdedeu, Josep; Bellosillo, Beatriz; Besses, Carles; Abdel-Wahab, Omar; Kucine, Nicole; Sun, Shao-Cong; Song, Guangchan; Mullighan, Charles C.; Levine, Ross L.; Rajewsky, Klaus; Aifantis, Iannis; Bigas, Anna

    2010-01-01

    SUMMARY It was previously shown that the NF-κB pathway is downstream of oncogenic Notch1 in T cell acute lymphoblastic leukemia (T-ALL). Here we visualize Notch-induced NF-κB activation using both human T-ALL cell lines and animal models. We demonstrate that Hes1, a canonical Notch target and transcriptional repressor, is responsible for sustaining IKK activation in T-ALL. Hes1 exerts its effects by repressing the deubiquitinase CYLD, a negative IKK complex regulator. CYLD expression was found to be significantly suppressed in primary T-ALL. Finally, we demonstrate that IKK inhibition is a promising option for the targeted therapy of T-ALL as specific suppression of IKK expression and function affected both the survival of human T-ALL cells and the maintenance of the disease in vivo. PMID:20832754

  1. The Notch/Hes1 pathway sustains NF-κB activation through CYLD repression in T cell leukemia.

    PubMed

    Espinosa, Lluis; Cathelin, Severine; D'Altri, Teresa; Trimarchi, Thomas; Statnikov, Alexander; Guiu, Jordi; Rodilla, Veronica; Inglés-Esteve, Julia; Nomdedeu, Josep; Bellosillo, Beatriz; Besses, Carles; Abdel-Wahab, Omar; Kucine, Nicole; Sun, Shao-Cong; Song, Guangchan; Mullighan, Charles C; Levine, Ross L; Rajewsky, Klaus; Aifantis, Iannis; Bigas, Anna

    2010-09-14

    It was previously shown that the NF-κB pathway is downstream of oncogenic Notch1 in T cell acute lymphoblastic leukemia (T-ALL). Here, we visualize Notch-induced NF-κB activation using both human T-ALL cell lines and animal models. We demonstrate that Hes1, a canonical Notch target and transcriptional repressor, is responsible for sustaining IKK activation in T-ALL. Hes1 exerts its effects by repressing the deubiquitinase CYLD, a negative IKK complex regulator. CYLD expression was found to be significantly suppressed in primary T-ALL. Finally, we demonstrate that IKK inhibition is a promising option for the targeted therapy of T-ALL as specific suppression of IKK expression and function affected both the survival of human T-ALL cells and the maintenance of the disease in vivo. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kuncharin, Yanin; Sangphech, Naunpun; Kueanjinda, Patipark

    The Notch signaling pathway plays important roles in tumorigenesis in a context-dependent manner. In human cervical cancer, alterations in Notch signaling have been reported, and both tumor-suppressing and tumor-promoting roles of Notch signaling have been proposed; however, the precise molecular mechanisms governing these roles in cervical cancer remain controversial. MAML is a transcriptional co-activator originally identified by its role in Notch signaling. Recent evidence suggests that it also plays a role in other signaling pathways, such as the p53 and {beta}-catenin pathways. MAML is required for stable formation of Notch transcriptional complexes at the promoters of Notch target genes. Chromosomalmore » translocations affecting MAML have been shown to promote tumorigenesis. In this study, we used a truncated dominant-negative MAML1 (DN-MAML) to investigate the role of MAML in HPV-positive cervical cancer cell lines. Three human cervical cancer cell lines (HeLa, SiHa and CaSki) expressed all Notch receptors and the Notch target genes Hes1 and MAML1. Among these 3 cell lines, constitutive appearance of cleaved Notch1 was found only in CaSki cells, which suggests that Notch1 is constitutively activated in this cell line. Gamma secretase inhibitor (GSI) treatment, which suppresses Notch receptor activation, completely abrogated this form of Notch1 but had no effect on cell viability. Overexpression of DN-MAML by retroviral transduction in CaSki cells resulted in significant decreases in the mRNA levels of Hes1 and Notch1 but had no effects on the levels of MAML1, p53 or HPV E6/E7. DN-MAML expression induced increased viability of CaSki cells without any effect on cell cycle progression or cell proliferation. In addition, clonogenic assay experiments revealed that overexpression of DN-MAML resulted in increased colony formation compared to the overexpression of the control vector. When the status of the NF-{kappa}B pathway was investigated, CaSki cells overexpressing DN-MAML exhibited loss of phospho-I{kappa}B{alpha}, decreased total I{kappa}B{alpha} and nuclear localization of NF-{kappa}B p65, which suggests that the NF-{kappa}B pathway is hyperactivated. Furthermore, increased level of cleaved Notch1 was detected when DN-MAML was expressed. When DN-MAML-overexpressing cells were treated with GSI, significantly decreased cell viability was observed, indicating that inhibition of Notch signaling using GSI treatment and DN-MAML expression negatively affects cell viability. Taken together, targeting Notch signaling using DN-MAML and GSI treatment may present a novel method to control cell viability in cervical cancer cells.« less

  3. Notch2 and Notch3 suppress the proliferation and mediate invasion of trophoblast cell lines

    PubMed Central

    Zhao, Wei-Xiu; Wu, Zhen-Ming; Liu, Wei

    2017-01-01

    ABSTRACT Notch signaling pathways play important roles in cell fate and many diseases, including preeclampsia, the dysregulation of which may be the main cause of maternal mortality. This study aimed to investigate the roles of Notch2 and Notch3 in proliferation and invasion in trophoblast cell lines (BeWo and JAR). Small hairpin RNAs targeting Notch2/Notch3 and Notch2/Notch3-overexpression vectors were designed, constructed and transfected into BeWo and JAR cells. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were then used to detect Notch2 and Notch3 mRNA and protein levels, and confirm the efficiency of silence and overexpression. Flow cytometry assays were conducted to evaluate the cell cycle of the two cell lines, and transwell assays were used to detect migration and invasion. Western blot analysis was also performed to show the alteration of the cell lines' physiological activities at protein level. When Notch2 was downregulated in BeWo cells, proliferation was dramatically promoted, while migration and invasion were significantly inhibited. When Notch2 was upregulated in JAR cells, proliferation was inhibited, but migration and invasion were promoted. After overexpression of Notch3 in BeWo cells, proliferation was downregulated, but migration and invasion were both upregulated. By contrast, the silencing of Notch3 expression in JAR cells significantly enhanced proliferation, but suppressed migration and invasion. These data indicated that Notch2 and Notch3 mediate the invasion and migration of BeWo and JAR cells, and may play a potential role in early onset severe preeclampsia. PMID:28606936

  4. Notch2 and Notch3 suppress the proliferation and mediate invasion of trophoblast cell lines.

    PubMed

    Zhao, Wei-Xiu; Wu, Zhen-Ming; Liu, Wei; Lin, Jian-Hua

    2017-08-15

    Notch signaling pathways play important roles in cell fate and many diseases, including preeclampsia, the dysregulation of which may be the main cause of maternal mortality. This study aimed to investigate the roles of Notch2 and Notch3 in proliferation and invasion in trophoblast cell lines (BeWo and JAR). Small hairpin RNAs targeting Notch2/Notch3 and Notch2/Notch3-overexpression vectors were designed, constructed and transfected into BeWo and JAR cells. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were then used to detect Notch2 and Notch3 mRNA and protein levels, and confirm the efficiency of silence and overexpression. Flow cytometry assays were conducted to evaluate the cell cycle of the two cell lines, and transwell assays were used to detect migration and invasion. Western blot analysis was also performed to show the alteration of the cell lines' physiological activities at protein level.When Notch2 was downregulated in BeWo cells, proliferation was dramatically promoted, while migration and invasion were significantly inhibited. When Notch2 was upregulated in JAR cells, proliferation was inhibited, but migration and invasion were promoted. After overexpression of Notch3 in BeWo cells, proliferation was downregulated, but migration and invasion were both upregulated. By contrast, the silencing of Notch3 expression in JAR cells significantly enhanced proliferation, but suppressed migration and invasion. These data indicated that Notch2 and Notch3 mediate the invasion and migration of BeWo and JAR cells, and may play a potential role in early onset severe preeclampsia. © 2017. Published by The Company of Biologists Ltd.

  5. Notch1 engagement by Delta-like-1 promotes differentiation of B lymphocytes to antibody-secreting cells

    PubMed Central

    Santos, Margarida Almeida; Sarmento, Leonor Morais; Rebelo, Manuel; Doce, Ana Agua; Maillard, Ivan; Dumortier, Alexis; Neves, Helia; Radtke, Freddy; Pear, Warren S.; Parreira, Leonor; Demengeot, Jocelyne

    2007-01-01

    Notch signaling regulates B and T lymphocyte development and T cell effector class decision. In this work, we tested whether Notch activity affects mature B cell activation and differentiation to antibody-secreting cells (ASC). We show increased frequency of ASC in cultures of splenic B cells activated with LPS or anti-CD40 when provided exogenous Notch ligand Delta-like-1 (Dll1). Our results indicate that Notch–Dll1 interaction releases a default pathway that otherwise inhibits Ig secretion upon B cell activation. Thus, Dll1 enhanced spontaneous Ig secretion by naturally activated marginal zone B and B1 cells and reversed the inhibition of ASC differentiation mediated by B cell receptor crosslinking during LPS. Moreover, suppression of Notch signaling in B cell expression of either a dominant-negative mutant form of Mastermind-like 1 or a null mutation of Notch1 not only prevented Dll1-mediated enhancement of ASC differentiation but also reduced dramatically LPS-induced Ig secretion. Finally, we show that Dll1 and Jagged-1 are differentially expressed in discrete areas of the spleen, and that the effect of Notch engagement on Ig secretion is ligand-specific. These results indicate that Notch ligands participate in the definition of the mature B cell microenvironment that influences their terminal differentiation. PMID:17878313

  6. The Challenge of Targeting Notch in Hematologic Malignancies

    PubMed Central

    Hernandez Tejada, Fiorela N.; Galvez Silva, Jorge R.; Zweidler-McKay, Patrick A.

    2014-01-01

    Notch signaling can play oncogenic and tumor suppressor roles depending on cell type. Hematologic malignancies encompass a wide range of transformed cells, and consequently the roles of Notch are diverse in these diseases. For example Notch is a potent T-cell oncogene, with >50% of T-cell acute lymphoblastic leukemia (T-ALL) cases carry activating mutations in the Notch1 receptor. Targeting Notch signaling in T-ALL with gamma-secretase inhibitors, which prevent Notch receptor activation, has shown pre-clinical activity, and is under evaluation clinically. In contrast, Notch signaling inhibits acute myeloblastic leukemia growth and survival, and although targeting Notch signaling in AML with Notch activators appears to have pre-clinical activity, no Notch agonists are clinically available at this time. As such, despite accumulating evidence about the biology of Notch signaling in different hematologic cancers, which provide compelling clinical promise, we are only beginning to target this pathway clinically, either on or off. In this review, we will summarize the evidence for oncogenic and tumor suppressor roles of Notch in a wide range of leukemias and lymphomas, and describe therapeutic opportunities for now and the future. PMID:24959528

  7. Targeting Notch1 signaling pathway positively affects the sensitivity of osteosarcoma to cisplatin by regulating the expression and/or activity of Caspase family

    PubMed Central

    2014-01-01

    Background The introduction of cisplatin has improved the long-term survival rate in osteosarcoma patients. However, some patients are intrinsically resistant to cisplatin. This study reported that the activation of Notch1 is positively correlated with cisplatin sensitivity, evidenced by both clinical and in vitro data. Results In this study, a total 8 osteosarcoma specimens were enrolled and divided into two groups according to their cancer chemotherapeutic drugs sensitivity examination results. The relationship between Notch1 expression and cisplatin sensitivity of osteosarcoma patients was detected by immunohistochemistry and semi-quantitative analysis. Subsequently, two typical osteosarcoma cell lines, Saos-2 and MG63, were selected to study the changes of cisplatin sensitivity by up-regulating (NICD1 plasmid transfeciton) or decreasing (gamma-secretase complex inhibitor DAPT) the activation state of Notch1 signaling pathway. Our results showed a significant correlation between the expression of Notch1 and cisplatin sensitivity in patient specimens. In vitro, Saos-2 with higher expression of Notch1 had significantly better cisplatin sensitivity than MG63 whose Notch1 level was relatively lower. By targeting regulation in vitro, the cisplatin sensitivity of Saos-2 and MG63 had significantly increased after the activation of Notch1 signaling pathway, and vice versa. Further mechanism investigation revealed that activation/inhibition of Notch1 sensitized/desensitized cisplatin-induced apoptosis, which probably depended on the changes in the activity of Caspase family, including Caspase 3, Caspase 8 and Caspase 9 in these cells. Conclusions Our data clearly demonstrated that Notch1 is critical for cisplatin sensitivity in osteosarcoma. It can be used as a molecular marker and regulator for cisplatin sensitivity in osteosarcoma patients. PMID:24894297

  8. Far infrared promotes wound healing through activation of Notch1 signaling.

    PubMed

    Hsu, Yung-Ho; Lin, Yuan-Feng; Chen, Cheng-Hsien; Chiu, Yu-Jhe; Chiu, Hui-Wen

    2017-11-01

    The Notch signaling pathway is critically involved in cell proliferation, differentiation, development, and homeostasis. Far infrared (FIR) has an effect that promotes wound healing. However, the underlying molecular mechanisms are unclear. In the present study, we employed in vivo and HaCaT (a human skin keratinocyte cell line) models to elucidate the role of Notch1 signaling in FIR-promoted wound healing. We found that FIR enhanced keratinocyte migration and proliferation. FIR induced the Notch1 signaling pathway in HaCaT cells and in a microarray dataset from the Gene Expression Omnibus database. We next determined the mRNA levels of NOTCH1 in paired normal and wound skin tissues derived from clinical patients using the microarray dataset and Ingenuity Pathway Analysis software. The result indicated that the Notch1/Twist1 axis plays important roles in wound healing and tissue repair. In addition, inhibiting Notch1 signaling decreased the FIR-enhanced proliferation and migration. In a full-thickness wound model in rats, the wounds healed more rapidly and the scar size was smaller in the FIR group than in the light group. Moreover, FIR could increase Notch1 and Delta1 in skin tissues. The activation of Notch1 signaling may be considered as a possible mechanism for the promoting effect of FIR on wound healing. FIR stimulates keratinocyte migration and proliferation. Notch1 in keratinocytes has an essential role in FIR-induced migration and proliferation. NOTCH1 promotes TWIST1-mediated gene expression to assist wound healing. FIR might promote skin wound healing in a rat model. FIR stimulates keratinocyte migration and proliferation. Notch1 in keratinocytes has an essential role in FIR-induced migration and proliferation. NOTCH1 promotes TWIST1-mediated gene expression to assist wound healing. FIR might promote skin wound healing in a rat model.

  9. Novel cell culture technique for primary ductal carcinoma in situ: role of Notch and epidermal growth factor receptor signaling pathways.

    PubMed

    Farnie, Gillian; Clarke, Robert B; Spence, Katherine; Pinnock, Natasha; Brennan, Keith; Anderson, Neil G; Bundred, Nigel J

    2007-04-18

    The epidermal growth factor receptor (EGFR) and Notch signaling pathways have been implicated in self-renewal of normal breast stem cells. We investigated the involvement of these signaling pathways in ductal carcinoma in situ (DCIS) of the breast. Samples of normal breast tissue (n = 15), pure DCIS tissue of varying grades (n = 35), and DCIS tissue surrounding an invasive cancer (n = 7) were used for nonadherent (i.e., mammosphere) culture. Mammosphere cultures were treated at day 0 with gefitinib (an EGFR inhibitor), DAPT (N-[N-(3,5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester) (a gamma-secretase inhibitor), or Notch 4-neutralizing antibody. Mammosphere-forming efficiency (MFE) was calculated by dividing the number of mammospheres of 60 microm or more formed by the number of single cells seeded and is expressed as a percentage. The Notch 1 intracellular domain (NICD) was detected immunohistochemically in paraffin-embedded DCIS tissue from 50 patients with at least 60 months of follow-up. All statistical tests were two-sided. DCIS had a greater MFE than normal breast tissue (1.5% versus 0.5%, difference = 1%, 95% confidence interval [CI] = 0.62% to 1.25%, P<.001). High-grade DCIS had a greater MFE than low-grade DCIS (1.6% versus 1.09%, difference = 0.51%, 95% CI = 0.07% to 0.94%, P = .01). The MFE of high-grade DCIS treated with gefitinib in the absence of exogenous EGF was lower than that of high-grade DCIS treated with mammosphere medium lacking gefitinib and exogenous EGF (0.56% versus 1.36%, difference 0.8%, 95% CI = 0.33% to 1.4%, P = .004). Increased Notch signaling as detected by NICD staining was associated with recurrence at 5 years (P = .012). DCIS MFE was reduced when Notch signaling was inhibited using either DAPT (0.89% versus 0.51%, difference = 0.38%, 95% CI = 0.2% to 0.6%, P<.001) or a Notch 4-neutralizing antibody (0.97% versus 0.2%, difference = 0.77%, 95% CI = 0.52% to 1.0%, P<.001). We describe a novel primary culture technique for DCIS. Inhibition of the EGFR or Notch signaling pathways reduced DCIS MFE.

  10. Serum From Advanced Heart Failure Patients Promotes Angiogenic Sprouting and Affects the Notch Pathway in Human Endothelial Cells

    PubMed Central

    Pannella, Micaela; Caliceti, Cristiana; Fortini, Francesca; Aquila, Giorgio; Sega, Francesco Vieceli Dalla; Pannuti, Antonio; Fortini, Cinzia; Morelli, Marco Bruno; Fucili, Alessandro; Francolini, Gloria; Voltan, Rebecca; Secchiero, Paola; Dinelli, GiovannI; Leoncini, Emanuela; Ferracin, Manuela; Hrelia, Silvana; Miele, Lucio; Rizzo, Paola

    2017-01-01

    It is unknown whether components present in heart failure (HF) patients' serum provide an angiogenic stimulus. We sought to determine whether serum from HF patients affects angiogenesis and its major modulator, the Notch pathway, in human umbilical vein endothelial cells (HUVECs). In cells treated with serum from healthy subjects or from patients at different HF stage we determined: (1) Sprouting angiogenesis, by measuring cells network (closed tubes) in collagen gel. (2) Protein levels of Notch receptors 1, 2, 4, and ligands Jagged1, Delta-like4. We found a higher number of closed tubes in HUVECs treated with advanced HF patients serum in comparison with cells treated with serum from mild HF patients or controls. Furthermore, as indicated by the reduction of the active form of Notch4 (N4IC) and of Jagged1, advanced HF patients serum inhibited Notch signalling in HUVECs in comparison with mild HF patients' serum and controls. The circulating levels of NT-proBNP (N-terminal of the pro-hormone brain natriuretic peptide), a marker for the detection and evalutation of HF, were positively correlated with the number of closed tubes (r = 0.485) and negatively with Notch4IC and Jagged1 levels in sera-treated cells (r = −0.526 and r = −0.604, respectively). In conclusion, we found that sera from advanced HF patients promote sprouting angiogenesis and dysregulate Notch signaling in HUVECs. Our study provides in vitro evidence of an angiogenic stimulus arising during HF progression and suggests a role for the Notch pathway in it. PMID:26987674

  11. Wnt and Notch Pathways Have Interrelated Opposing Roles on Prostate Progenitor Cell Proliferation and Differentiation

    PubMed Central

    Shahi, Payam; Seethammagari, Mamatha R.; Valdez, Joseph M.; Xin, Li; Spencer, David M.

    2011-01-01

    Tissue stem cells are capable of both self-renewal and differentiation to maintain a constant stem cell population and give rise to the plurality of cells within a tissue. Wnt signaling has been previously identified as a key mediator for the maintenance of tissue stem cells; however, possible cross-regulation with other developmentally critical signaling pathways involved in adult tissue homeostasis, such as Notch, is not well understood. By using an in vitro prostate stem cell colony (“prostasphere”) formation assay and in vivo prostate reconstitution experiments, we demonstrate that Wnt pathway induction on Sca-1+ CD49f+ basal/stem cells (B/SCs) promotes expansion of the basal epithelial compartment with noticeable increases in “triple positive” (cytokeratin [CK] 5+, CK8+, p63+) prostate progenitor cells, concomitant with upregulation of known Wnt target genes involved in cell-cycle induction. Moreover, Wnt induction affects expression of epithelial-to-mesenchymal transition signature genes, suggesting a possible mechanism for priming B/SC to act as potential tumor-initiating cells. Interestingly, induction of Wnt signaling in B/SCs results in downregulation of Notch1 transcripts, consistent with its postulated antiproliferative role in prostate cells. In contrast, induction of Notch signaling in prostate progenitors inhibits their proliferation and disrupts prostasphere formation. In vivo prostate reconstitution assays further demonstrate that induction of Notch in B/SCs disrupts proper acini formation in cells expressing the activated Notch1 allele, Notch-1 intracellular domain. These data emphasize the importance of Wnt/Notch cross-regulation in adult stem cell biology and suggest that Wnt signaling controls the proliferation and/or maintenance of epithelial progenitors via modulation of Notch signaling. PMID:21308863

  12. Downregulation of HIF-1a sensitizes U251 glioma cells to the temozolomide (TMZ) treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tang, Jun-Hai; Ma, Zhi-Xiong; Huang, Guo-Hao

    Purpose: The aim of this study was to investigate the effect of downregulation of HIF-1α gene on human U251 glioma cells and examine the consequent changes of TMZ induced effects and explore the molecular mechanisms. Methods: U251 cell line stably expressing HIF-1α shRNA was acquired via lentiviral vector transfection. The mRNA and protein expression alterations of genes involved in our study were determined respectively by qRT-PCR and Western blot. Cell proliferation was measured by MTT assay and colony formation assay, cell invasion/migration capacity was determined by transwell invasion assay/wound healing assay, and cell apoptosis was detected by flow cytometry. Results:more » We successfully established a U251 cell line with highly efficient HIF-1α knockdown. HIF-1a downregulation sensitized U251 cells to TMZ treatment and enhanced the proliferation-inhibiting, invasion/migration-suppressing, apoptosis-inducing and differentiation-promoting effects exerted by TMZ. The related molecular mechanisms demonstrated that expression of O{sup 6}-methylguanine DNA methyltransferase gene (MGMT) and genes of Notch1 pathway were significantly upregulated by TMZ treatment. However, this upregulation was abrogated by HIF-1α knockdown. We further confirmed important regulatory roles of HIF-1α in the expression of MGMT and activation of Notch1 pathways. Conclusion: HIF-1α downregulation sensitizes U251 glioma cells to the temozolomide treatment via inhibiting MGMT expression and Notch1 pathway activation. - Highlights: • TMZ caused more significant proliferation inhibition and apoptosis in U251 cells after downregulating HIF-1α. • Under TMZ treatment, HIF-1 downregulated U251 cells exhibited weaker mobility and more differentiated state. • TMZ caused MGMT over-expression and Notch1 pathway activation, which could be abrogated by HIF-1α downregulation.« less

  13. Evolution of the Chordate Regeneration Blastema: Differential Gene Expression and Conserved Role of Notch Signaling During Siphon Regeneration in the Ascidian Ciona

    PubMed Central

    Hamada, Mayuko; Goricki, Spela; Byerly, Mardi S.; Satoh, Noriyuki; Jeffery, William R.

    2015-01-01

    The regeneration of the oral siphon (OS) and other distal structures in the ascidian Ciona intestinalis occurs by epimorphosis involving the formation of a blastema of proliferating cells. Despite the longstanding use of Ciona as a model in molecular developmental biology, regeneration in this system has not been previously explored by molecular analysis. Here we have employed microarray analysis and quantitative real time RT-PCR to identify genes with differential expression profiles during OS regeneration. The majority of differentially expressed genes were downregulated during OS regeneration, suggesting roles in normal growth and homeostasis. However, a subset of differentially expressed genes was upregulated in the regenerating OS, suggesting functional roles during regeneration. Among the upregulated genes were key members of the Notch signaling pathway, including those encoding the delta and jagged ligands, two fringe modulators, and to a lesser extent the notch receptor. In situ hybridization showed a complementary pattern of delta1 and notch gene expression in the blastema of the regenerating OS. Chemical inhibition of the Notch signaling pathway reduced the levels of cell proliferation in the branchial sac, a stem cell niche that contributes progenitor cells to the regenerating OS, and in the OS regeneration blastema, where siphon muscle fibers eventually re-differentiate. Chemical inhibition also prevented the replacement of oral siphon pigment organs, sensory receptors rimming the entrance of the OS, and siphon muscle fibers, but had no effects on the formation of the wound epidermis. Since Notch signaling is involved in the maintenance of proliferative activity in both the Ciona and vertebrate regeneration blastema, the results suggest a conserved evolutionary role of this signaling pathway in chordate regeneration. The genes identified in this investigation provide the foundation for future molecular analysis of OS regeneration. PMID:26206613

  14. Structural and functional analysis of the repressor complex in the Notch signaling pathway of Drosophila melanogaster

    PubMed Central

    Maier, Dieter; Kurth, Patricia; Schulz, Adriana; Russell, Andrew; Yuan, Zhenyu; Gruber, Kim; Kovall, Rhett A.; Preiss, Anette

    2011-01-01

    In metazoans, the highly conserved Notch pathway drives cellular specification. On receptor activation, the intracellular domain of Notch assembles a transcriptional activator complex that includes the DNA-binding protein CSL, a composite of human C-promoter binding factor 1, Suppressor of Hairless of Drosophila melanogaster [Su(H)], and lin-12 and Glp-1 phenotype of Caenorhabditis elegans. In the absence of ligand, CSL represses Notch target genes. However, despite the structural similarity of CSL orthologues, repression appears largely diverse between organisms. Here we analyze the Notch repressor complex in Drosophila, consisting of the fly CSL protein, Su(H), and the corepressor Hairless, which recruits general repressor proteins. We show that the C-terminal domain of Su(H) is necessary and sufficient for forming a high-affinity complex with Hairless. Mutations in Su(H) that affect interactions with Notch and Mastermind have no effect on Hairless binding. Nonetheless, we demonstrate that Notch and Hairless compete for CSL in vitro and in cell culture. In addition, we identify a site in Hairless that is crucial for binding Su(H) and subsequently show that this Hairless mutant is strongly impaired, failing to properly assemble the repressor complex in vivo. Finally, we demonstrate Hairless-mediated inhibition of Notch signaling in a cell culture assay, which hints at a potentially similar repression mechanism in mammals that might be exploited for therapeutic purposes. PMID:21737682

  15. Human prostate luminal cell differentiation requires NOTCH3 induction by p38-MAPK and MYC.

    PubMed

    Frank, Sander B; Berger, Penny L; Ljungman, Mats; Miranti, Cindy K

    2017-06-01

    Many pathways dysregulated in prostate cancer are also involved in epithelial differentiation. To better understand prostate tumor initiation, we sought to investigate specific genes and mechanisms required for normal basal to luminal cell differentiation. Utilizing human prostate basal epithelial cells and an in vitro differentiation model, we tested the hypothesis that regulation of NOTCH3 by the p38 MAPK family (hereafter p38-MAPK), via MYC, is required for luminal differentiation. Inhibition (SB202190 and BIRB796) or knockdown of p38α (also known as MAPK14) and/or p38δ (also known as MAPK13) prevented proper differentiation. Additionally, treatment with a γ-secretase inhibitor (RO4929097) or knockdown of NOTCH1 and/or NOTCH3 greatly impaired differentiation and caused luminal cell death. Constitutive p38-MAPK activation through MKK6(CA) increased NOTCH3 (but not NOTCH1) mRNA and protein levels, which was diminished upon MYC inhibition (10058-F4 and JQ1) or knockdown. Furthermore, we validated two NOTCH3 enhancer elements through a combination of enhancer (e)RNA detection (BruUV-seq) and luciferase reporter assays. Finally, we found that the NOTCH3 mRNA half-life increased during differentiation or upon acute p38-MAPK activation. These results reveal a new connection between p38-MAPK, MYC and NOTCH signaling, demonstrate two mechanisms of NOTCH3 regulation and provide evidence for NOTCH3 involvement in prostate luminal cell differentiation. © 2017. Published by The Company of Biologists Ltd.

  16. Paired related homeobox 1 is associated with the invasive properties of glioblastoma cells.

    PubMed

    Sugiyama, Mai; Hasegawa, Hitoki; Ito, Satoko; Sugiyama, Kazuya; Maeda, Masao; Aoki, Kosuke; Wakabayashi, Toshihiko; Hamaguchi, Michinari; Natsume, Atsushi; Senga, Takeshi

    2015-03-01

    Glioblastoma is a highly proliferative and invasive tumor. Despite extensive efforts to develop treatments for glioblastoma, the currently available therapies have only limited effects. To develop novel strategies for glioblastoma treatment, it is crucial to elucidate the molecular mechanisms that promote the invasive properties of glioblastoma. In the present study, we showed that the paired related homeobox 1 (PRRX1) is associated with glioblastoma cell invasion. The depletion of PRRX1 suppressed the invasion and neurosphere formation of glioblastoma cells. Conversely, the exogenous expression of PRRX1 promoted invasion. The Notch signaling pathway, which is an evolutionarily conserved pathway that is essential for developmental processes, plays an important role in the tumorigenesis of glioblastoma. The expression of PRRX1 induced the activation of Notch signaling, and the inhibition of Notch signaling suppressed PRRX1-mediated cell invasion. Our results indicate that activation of Notch signaling by PRRX1 is associated with the promotion of glioblastoma cell invasion.

  17. The common oncogenomic program of NOTCH1 and NOTCH3 signaling in T-cell acute lymphoblastic leukemia.

    PubMed

    Choi, Sung Hee; Severson, Eric; Pear, Warren S; Liu, Xiaole S; Aster, Jon C; Blacklow, Stephen C

    2017-01-01

    Notch is a major oncogenic driver in T cell acute lymphoblastic leukemia (T-ALL), in part because it binds to an enhancer that increases expression of MYC. Here, we exploit the capacity of activated NOTCH1 and NOTCH3 to induce T-ALL, despite substantial divergence in their intracellular regions, as a means to elucidate a broad, common Notch-dependent oncogenomic program through systematic comparison of the transcriptomes and Notch-bound genomic regulatory elements of NOTCH1- and NOTCH3-dependent T-ALL cells. ChIP-seq studies show a high concordance of functional NOTCH1 and NOTCH3 genomic binding sites that are enriched in binding motifs for RBPJ, the transcription factor that recruits activated Notch to DNA. The interchangeability of NOTCH1 and NOTCH3 was confirmed by rescue of NOTCH1-dependent T-ALL cells with activated NOTCH3 and vice versa. Despite remarkable overall similarity, there are nuanced differences in chromatin landscapes near critical common Notch target genes, most notably at a Notch-dependent enhancer that regulates MYC, which correlates with responsiveness to Notch pathway inhibitors. Overall, a common oncogenomic program driven by binding of either Notch is sufficient to maintain T-ALL cell growth, whereas cell-context specific differences appear to influence the response of T-ALL cells to Notch inhibition.

  18. The common oncogenomic program of NOTCH1 and NOTCH3 signaling in T-cell acute lymphoblastic leukemia

    PubMed Central

    Pear, Warren S.; Liu, Xiaole S.; Aster, Jon C.

    2017-01-01

    Notch is a major oncogenic driver in T cell acute lymphoblastic leukemia (T-ALL), in part because it binds to an enhancer that increases expression of MYC. Here, we exploit the capacity of activated NOTCH1 and NOTCH3 to induce T-ALL, despite substantial divergence in their intracellular regions, as a means to elucidate a broad, common Notch-dependent oncogenomic program through systematic comparison of the transcriptomes and Notch-bound genomic regulatory elements of NOTCH1- and NOTCH3-dependent T-ALL cells. ChIP-seq studies show a high concordance of functional NOTCH1 and NOTCH3 genomic binding sites that are enriched in binding motifs for RBPJ, the transcription factor that recruits activated Notch to DNA. The interchangeability of NOTCH1 and NOTCH3 was confirmed by rescue of NOTCH1-dependent T-ALL cells with activated NOTCH3 and vice versa. Despite remarkable overall similarity, there are nuanced differences in chromatin landscapes near critical common Notch target genes, most notably at a Notch-dependent enhancer that regulates MYC, which correlates with responsiveness to Notch pathway inhibitors. Overall, a common oncogenomic program driven by binding of either Notch is sufficient to maintain T-ALL cell growth, whereas cell-context specific differences appear to influence the response of T-ALL cells to Notch inhibition. PMID:29023469

  19. Notch3 signaling-mediated melanoma-endothelial crosstalk regulates melanoma stem-like cell homeostasis and niche morphogenesis.

    PubMed

    Hsu, Mei-Yu; Yang, Moon Hee; Schnegg, Caroline I; Hwang, Soonyean; Ryu, Byungwoo; Alani, Rhoda M

    2017-06-01

    Melanoma is among the most virulent cancers, owing to its propensity to metastasize and its resistance to current therapies. The treatment failure is largely attributed to tumor heterogeneity, particularly subpopulations possessing stem cell-like properties, ie, melanoma stem-like cells (MSLCs). Evidence indicates that the MSLC phenotype is malleable and may be acquired by non-MSLCs through phenotypic switching upon appropriate stimuli, the so-called 'dynamic stemness'. Since the phenotypic characteristics and functional integrity of MSLCs depend on their vascular niche, using a two-dimensional (2D) melanoma-endothelium co-culture model, where the MSLC niche is recapitulated in vitro, we identified Notch3 signaling pathway as a micro-environmental cue governing MSLC phenotypic plasticity via pathway-specific gene expression arrays. Accordingly, lentiviral shRNA-mediated Notch3 knockdown (KD) in melanoma cell lines exhibiting high levels of endogenous Notch3 led to retarded/abolished tumorigenicity in vivo through both depleting MSLC fractions, evinced by MSLC marker downregulation (eg, CD133 and CD271); and impeding the MSLC niche, corroborated by the attenuated tumor angiogenesis as well as vasculogenic mimicry. In contrast, Notch3 KD affected neither tumor growth nor MSLC subsets in a melanoma cell line with relatively low endogenous Notch3 expression. Thus, Notch3 signaling may facilitate MSLC plasticity and niche morphogenesis in a cell context-dependent manner. Our findings illustrate Notch3 as a molecular switch driving melanoma heterogeneity, and provide the biological rationale for Notch inhibition as a promising therapeutic option.

  20. Effects of an inhibitor of the γ-secretase complex on proliferation and apoptotic parameters in a FOXL2-mutated granulosa tumor cell line (KGN).

    PubMed

    Irusta, Griselda; Pazos, Maria Camila; Maidana, Camila Pazos; Abramovich, Dalhia; De Zúñiga, Ignacio; Parborell, Fernanda; Tesone, Marta

    2013-07-01

    Ovarian granulosa cell tumors (GCTs) represent 3%-5% of all ovarian malignancies. Treatments have limited proven efficacy and biologically targeted treatment is lacking. The aim of this study was to investigate the role of Notch signaling in the proliferation, steroidogenesis, apoptosis, and phosphatidylinositol 3-kinase (PI3K)/AKT pathway in a FOXL2-mutated granulosa tumor cell line (KGN) representative of the adult form of GCTs. When Notch signaling is initiated, the receptors expose a cleavage site in the extracellular domain to the metalloproteinase TACE and, following this cleavage, Notch undergoes another cleavage mediated by the presenilin-gamma-secretase complex. To achieve our goal, DAPT, an inhibitor of the gamma-secretase complex, was used to investigate the role of the Notch system in parameters associated with cell growth and death, using a human granulosa cell tumor line (KGN) as an experimental model. We observed that JAGGED1, DLL4, NOTCH1, and NOTCH4 were highly expressed in KGN cells as compared to granulosa-lutein cells obtained from assisted reproductive techniques patients. The proliferation and viability of KGN cells, as well as progesterone and estradiol production, decreased in the presence of 20 μM DAPT. Apoptotic parameters like PARP and caspase 8 cleavages, BAX, and BCLXs increased in KGN cells cultured with DAPT, whereas others such as BCL2, BCLXl, FAS, and FAS ligand did not change. AKT phosphorylation decreased and PTEN protein increased when Notch signaling was inhibited in KGN cells. We conclude that the Notch system acts as a survival pathway in KGN cells, and might be interacting with the PI3K/AKT pathway.

  1. Notch3 Maintains Luminal Phenotype and Suppresses Tumorigenesis and Metastasis of Breast Cancer via Trans-Activating Estrogen Receptor-α.

    PubMed

    Dou, Xiao-Wei; Liang, Yuan-Ke; Lin, Hao-Yu; Wei, Xiao-Long; Zhang, Yong-Qu; Bai, Jing-Wen; Chen, Chun-Fa; Chen, Min; Du, Cai-Wen; Li, Yao-Chen; Tian, Jie; Man, Kwan; Zhang, Guo-Jun

    2017-01-01

    The luminal A phenotype is the most common breast cancer subtype and is characterized by estrogen receptor α expression (ERα). Identification of the key regulator that governs the luminal phenotype of breast cancer will clarify the pathogenic mechanism and provide novel therapeutic strategies for this subtype of cancer. ERα signaling pathway sustains the epithelial phenotype and inhibits the epithelial-mesenchymal transition (EMT) of breast cancer. In this study, we demonstrate that Notch3 positively associates with ERα in both breast cancer cell lines and human breast cancer tissues. We found that overexpression of Notch3 intra-cellular domain, a Notch3 active form (N3ICD), in ERα negative breast cancer cells re-activated ERα, while knock-down of Notch3 reduced ERα transcript and proteins, with alteration of down-stream genes, suggesting its ability to regulate ERα. Mechanistically, our results show that Notch3 specifically binds to the CSL binding element of the ERα promoter and activates ERα expression. Moreover, Notch3 suppressed EMT, while suppression of Notch3 promoted EMT in cellular assay. Overexpressing N3ICD in triple-negative breast cancer suppressed tumorigenesis and metastasis in vivo . Conversely, depletion of Notch3 in luminal breast cancer promoted metastasis in vivo . Furthermore, Notch3 transcripts were significantly associated with prolonged relapse-free survival in breast cancer, in particular in ERα positive breast cancer patients. Our observations demonstrate that Notch3 governs the luminal phenotype via trans-activating ERα expression in breast cancer. These findings delineate the role of a Notch3/ERα axis in maintaining the luminal phenotype and inhibiting tumorigenesis and metastasis in breast cancer, providing a novel strategy to re-sensitize ERα negative or low-expressing breast cancers to hormone therapy.

  2. Notch3 Maintains Luminal Phenotype and Suppresses Tumorigenesis and Metastasis of Breast Cancer via Trans-Activating Estrogen Receptor-α

    PubMed Central

    Dou, Xiao-Wei; Liang, Yuan-Ke; Lin, Hao-Yu; Wei, Xiao-Long; Zhang, Yong-Qu; Bai, Jing-Wen; Chen, Chun-Fa; Chen, Min; Du, Cai-Wen; Li, Yao-Chen; Tian, Jie; Man, Kwan; Zhang, Guo-Jun

    2017-01-01

    The luminal A phenotype is the most common breast cancer subtype and is characterized by estrogen receptor α expression (ERα). Identification of the key regulator that governs the luminal phenotype of breast cancer will clarify the pathogenic mechanism and provide novel therapeutic strategies for this subtype of cancer. ERα signaling pathway sustains the epithelial phenotype and inhibits the epithelial-mesenchymal transition (EMT) of breast cancer. In this study, we demonstrate that Notch3 positively associates with ERα in both breast cancer cell lines and human breast cancer tissues. We found that overexpression of Notch3 intra-cellular domain, a Notch3 active form (N3ICD), in ERα negative breast cancer cells re-activated ERα, while knock-down of Notch3 reduced ERα transcript and proteins, with alteration of down-stream genes, suggesting its ability to regulate ERα. Mechanistically, our results show that Notch3 specifically binds to the CSL binding element of the ERα promoter and activates ERα expression. Moreover, Notch3 suppressed EMT, while suppression of Notch3 promoted EMT in cellular assay. Overexpressing N3ICD in triple-negative breast cancer suppressed tumorigenesis and metastasis in vivo. Conversely, depletion of Notch3 in luminal breast cancer promoted metastasis in vivo. Furthermore, Notch3 transcripts were significantly associated with prolonged relapse-free survival in breast cancer, in particular in ERα positive breast cancer patients. Our observations demonstrate that Notch3 governs the luminal phenotype via trans-activating ERα expression in breast cancer. These findings delineate the role of a Notch3/ERα axis in maintaining the luminal phenotype and inhibiting tumorigenesis and metastasis in breast cancer, providing a novel strategy to re-sensitize ERα negative or low-expressing breast cancers to hormone therapy. PMID:29109797

  3. (−)-Epigallocatechin Gallate Targets Notch to Attenuate the Inflammatory Response in the Immediate Early Stage in Human Macrophages

    PubMed Central

    Wang, Tengfei; Xiang, Zemin; Wang, Ya; Li, Xi; Fang, Chongye; Song, Shuang; Li, Chunlei; Yu, Haishuang; Wang, Han; Yan, Liang; Hao, Shumei; Wang, Xuanjun; Sheng, Jun

    2017-01-01

    Inflammation plays important roles at different stages of diabetes mellitus, tumorigenesis, and cardiovascular diseases. (−)-Epigallocatechin gallate (EGCG) can attenuate inflammatory responses effectively. However, the immediate early mechanism of EGCG in inflammation remains unclear. Here, we showed that EGCG attenuated the inflammatory response in the immediate early stage of EGCG treatment by shutting off Notch signaling and that the effect did not involve the 67-kDa laminin receptor, the common receptor for EGCG. EGCG eliminated mature Notch from the cell membrane and the nuclear Notch intercellular domain, the active form of Notch, within 2 min by rapid degradation via the proteasome pathway. Transcription of the Notch target gene was downregulated simultaneously. Knockdown of Notch 1/2 expression by RNA interference impaired the downregulation of the inflammatory response elicited by EGCG. Further study showed that EGCG inhibited lipopolysaccharide-induced inflammation and turned off Notch signaling in human primary macrophages. Taken together, our results show that EGCG targets Notch to regulate the inflammatory response in the immediate early stage. PMID:28443100

  4. Tangeretin enhances radiosensitivity and inhibits the radiation-induced epithelial-mesenchymal transition of gastric cancer cells.

    PubMed

    Zhang, Xukui; Zheng, Luming; Sun, Yinggang; Wang, Tianxiao; Wang, Baocheng

    2015-07-01

    Irradiation has been reported to increase radioresistance and epithelial-mesenchymal transition (EMT) in gastric cancer (GC) cells. The Notch pathway is critically implicated in cancer EMT and radioresistance. In the present study, we investigated the use of a Notch-1 inhibiting compound as a novel therapeutic candidate to regulate radiation-induced EMT in GC cells. According to previous screening, tangeretin, a polymethoxylated flavonoid from citrus fruits was selected as a Notch-1 inhibitor. Tangeretin enhanced the radiosensitivity of GC cells as demonstrated by MTT and colony formation assays. Tangeretin also attenuated radiation-induced EMT, invasion and migration in GC cells, accompanied by a decrease in Notch-1, Jagged1/2, Hey-1 and Hes-1 expressions. Tangeretin triggered the upregulation of miR-410, a tumor-suppressive microRNA. Furthermore, re-expression of miR-410 prevented radiation-induced EMT and cell invasion. An in vivo tumor xenograft model confirmed the antimetastasis effect of tangeretin as we observed in vitro. In nude mice, tumor size was considerably diminished by radiation plus tangeretin co-treatment. Tangeretin almost completely inhibited lung metastasis induced by irradiation. Tangeretin may be a novel antimetastatic agent for radiotherapy.

  5. GPER activates Notch signaling in breast cancer cells and cancer-associated fibroblasts (CAFs).

    PubMed

    Pupo, Marco; Pisano, Assunta; Abonante, Sergio; Maggiolini, Marcello; Musti, Anna Maria

    2014-01-01

    The G protein-coupled receptor GPR30/GPER has been shown to mediate rapid effects of 17β-estradiol (E2) in diverse types of cancer cells. Here, we provide evidence for a novel crosstalk between GPER and the Notch signaling pathway in breast cancer cells and cancer-associated fibroblasts (CAFs). We show that E2 and the GPER selective ligand G-1 induce both the γ-secretase-dependent activation of Notch-1 and the expression of the Notch target gene Hes-1. These inductions are prevented by knocking down GPER or by using a dominant-negative mutant of the Notch transcriptional co-activator Master-mind like-1 (DN-MAML-1), hence suggesting the involvement of GPER in the Notch-dependent transcription. By performing chromatin-immunoprecipitation experiments and luciferase assays, we also demonstrate that E2 and G-1 induce the recruitment of the intracellular domain of Notch-1 (N1ICD) to the Hes-1 promoter and the transactivation of a Hes-1-reporter gene, respectively. Functionally, the E2 and G-1-induced migration of breast cancer cells and CAFs is abolished in presence of the γ-secretase inhibitor GSI or DN-MAML-1, which both inhibit the Notch signaling pathway. In addition, we demonstrate that E2 and G-1 prevent the expression of VE-Cadherin, while both compounds induce the expression of Snail, a Notch target gene acting as a repressor of cadherins expression. Notably, both GSI and DN-MAML-1 abolish the up-regulation of Snail-1 by E2 and G-1, whereas the use of GSI rescues VE-Cadherin expression. Taken together, our results prove the involvement of the Notch signaling pathway in mediating the effects of estrogenic GPER signaling in breast cancer cells and CAFs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Regulation of Monocarboxylic Acid Transporter 1 Trafficking by the Canonical Wnt/β-Catenin Pathway in Rat Brain Endothelial Cells Requires Cross-talk with Notch Signaling*

    PubMed Central

    Sneve, Mary; Haroldson, Thomas A.; Smith, Jeffrey P.

    2016-01-01

    The transport of monocarboxylate fuels such as lactate, pyruvate, and ketone bodies across brain endothelial cells is mediated by monocarboxylic acid transporter 1 (MCT1). Although the canonical Wnt/β-catenin pathway is required for rodent blood-brain barrier development and for the expression of associated nutrient transporters, the role of this pathway in the regulation of brain endothelial MCT1 is unknown. Here we report expression of nine members of the frizzled receptor family by the RBE4 rat brain endothelial cell line. Furthermore, activation of the canonical Wnt/β-catenin pathway in RBE4 cells via nuclear β-catenin signaling with LiCl does not alter brain endothelial Mct1 mRNA but increases the amount of MCT1 transporter protein. Plasma membrane biotinylation studies and confocal microscopic examination of mCherry-tagged MCT1 indicate that increased transporter results from reduced MCT1 trafficking from the plasma membrane via the endosomal/lysosomal pathway and is facilitated by decreased MCT1 ubiquitination following LiCl treatment. Inhibition of the Notch pathway by the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester negated the up-regulation of MCT1 by LiCl, demonstrating a cross-talk between the canonical Wnt/β-catenin and Notch pathways. Our results are important because they show, for the first time, the regulation of MCT1 in cerebrovascular endothelial cells by the multifunctional canonical Wnt/β-catenin and Notch signaling pathways. PMID:26872974

  7. Enteric neural crest cells regulate vertebrate stomach patterning and differentiation.

    PubMed

    Faure, Sandrine; McKey, Jennifer; Sagnol, Sébastien; de Santa Barbara, Pascal

    2015-01-15

    In vertebrates, the digestive tract develops from a uniform structure where reciprocal epithelial-mesenchymal interactions pattern this complex organ into regions with specific morphologies and functions. Concomitant with these early patterning events, the primitive GI tract is colonized by the vagal enteric neural crest cells (vENCCs), a population of cells that will give rise to the enteric nervous system (ENS), the intrinsic innervation of the GI tract. The influence of vENCCs on early patterning and differentiation of the GI tract has never been evaluated. In this study, we report that a crucial number of vENCCs is required for proper chick stomach development, patterning and differentiation. We show that reducing the number of vENCCs by performing vENCC ablations induces sustained activation of the BMP and Notch pathways in the stomach mesenchyme and impairs smooth muscle development. A reduction in vENCCs also leads to the transdifferentiation of the stomach into a stomach-intestinal mixed phenotype. In addition, sustained Notch signaling activity in the stomach mesenchyme phenocopies the defects observed in vENCC-ablated stomachs, indicating that inhibition of the Notch signaling pathway is essential for stomach patterning and differentiation. Finally, we report that a crucial number of vENCCs is also required for maintenance of stomach identity and differentiation through inhibition of the Notch signaling pathway. Altogether, our data reveal that, through the regulation of mesenchyme identity, vENCCs act as a new mediator in the mesenchymal-epithelial interactions that control stomach development. © 2015. Published by The Company of Biologists Ltd.

  8. Proinflammatory Cytokine Tumor Necrosis Factor (TNF)-like Weak Inducer of Apoptosis (TWEAK) Suppresses Satellite Cell Self-renewal through Inversely Modulating Notch and NF-κB Signaling Pathways*

    PubMed Central

    Ogura, Yuji; Mishra, Vivek; Hindi, Sajedah M.; Kuang, Shihuan; Kumar, Ashok

    2013-01-01

    Satellite cell self-renewal is an essential process to maintaining the robustness of skeletal muscle regenerative capacity. However, extrinsic factors that regulate self-renewal of satellite cells are not well understood. Here, we demonstrate that TWEAK cytokine reduces the proportion of Pax7+/MyoD− cells (an index of self-renewal) on myofiber explants and represses multiple components of Notch signaling in satellite cell cultures. The number of Pax7+ cells is significantly increased in skeletal muscle of TWEAK knock-out (KO) mice compared with wild-type in response to injury. Furthermore, Notch signaling is significantly elevated in cultured satellite cells and in regenerating myofibers of TWEAK-KO mice. Forced activation of Notch signaling through overexpression of the Notch1 intracellular domain (N1ICD) rescued the TWEAK-mediated inhibition of satellite cell self-renewal. TWEAK also activates the NF-κB transcription factor in satellite cells and inhibition of NF-κB significantly improved the number of Pax7+ cells in TWEAK-treated cultures. Furthermore, our results demonstrate that a reciprocal interaction between NF-κB and Notch signaling governs the inhibitory effect of TWEAK on satellite cell self-renewal. Collectively, our study demonstrates that TWEAK suppresses satellite cell self-renewal through activating NF-κB and repressing Notch signaling. PMID:24151074

  9. Proinflammatory cytokine tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) suppresses satellite cell self-renewal through inversely modulating Notch and NF-κB signaling pathways.

    PubMed

    Ogura, Yuji; Mishra, Vivek; Hindi, Sajedah M; Kuang, Shihuan; Kumar, Ashok

    2013-12-06

    Satellite cell self-renewal is an essential process to maintaining the robustness of skeletal muscle regenerative capacity. However, extrinsic factors that regulate self-renewal of satellite cells are not well understood. Here, we demonstrate that TWEAK cytokine reduces the proportion of Pax7(+)/MyoD(-) cells (an index of self-renewal) on myofiber explants and represses multiple components of Notch signaling in satellite cell cultures. The number of Pax7(+) cells is significantly increased in skeletal muscle of TWEAK knock-out (KO) mice compared with wild-type in response to injury. Furthermore, Notch signaling is significantly elevated in cultured satellite cells and in regenerating myofibers of TWEAK-KO mice. Forced activation of Notch signaling through overexpression of the Notch1 intracellular domain (N1ICD) rescued the TWEAK-mediated inhibition of satellite cell self-renewal. TWEAK also activates the NF-κB transcription factor in satellite cells and inhibition of NF-κB significantly improved the number of Pax7(+) cells in TWEAK-treated cultures. Furthermore, our results demonstrate that a reciprocal interaction between NF-κB and Notch signaling governs the inhibitory effect of TWEAK on satellite cell self-renewal. Collectively, our study demonstrates that TWEAK suppresses satellite cell self-renewal through activating NF-κB and repressing Notch signaling.

  10. Control of endothelial cell tube formation by Notch ligand intracellular domain interactions with activator protein 1 (AP-1).

    PubMed

    Forghany, Zary; Robertson, Francesca; Lundby, Alicia; Olsen, Jesper V; Baker, David A

    2018-01-26

    Notch signaling is a ubiquitous signal transduction pathway found in most if not all metazoan cell types characterized to date. It is indispensable for cell differentiation as well as tissue growth, tissue remodeling, and apoptosis. Although the canonical Notch signaling pathway is well characterized, accumulating evidence points to the existence of multiple, less well-defined layers of regulation. In this study, we investigated the function of the intracellular domain (ICD) of the Notch ligand Delta-like 4 (DLL4). We provide evidence that the DLL4 ICD is required for normal DLL4 subcellular localization. We further show that it is cleaved and interacts with the JUN proto-oncogene, which forms part of the activator protein 1 (AP-1) transcription factor complex. Mechanistically, the DLL4 ICD inhibited JUN binding to DNA and thereby controlled the expression of JUN target genes, including DLL4 Our work further demonstrated that JUN strongly stimulates endothelial cell tube formation and that DLL4 constrains this process. These results raise the possibility that Notch/DLL4 signaling is bidirectional and suggest that the DLL4 ICD could represent a point of cross-talk between Notch and receptor tyrosine kinase (RTK) signaling. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Notch3/Akt signaling contributes to OSM-induced protection against cardiac ischemia/reperfusion injury.

    PubMed

    Zhang, Mingming; Wang, Chen; Hu, Jianqiang; Lin, Jie; Zhao, Zhijing; Shen, Min; Gao, Haokao; Li, Na; Liu, Min; Zheng, Pengfei; Qiu, Cuiting; Gao, Erhe; Wang, Haichang; Sun, Dongdong

    2015-09-01

    Oncostatin M (OSM) exhibits many unique biological activities by activating the Oβ receptor. However, its role in myocardial ischemia/reperfusion injury (I/R injury) in mice remains unknown. We investigated whether Notch3/Akt signaling is involved in the regulation of OSM-induced protection against cardiac I/R injury. The effects of OSM were assessed in mice that underwent myocardial I/R injury by OSM treatment or by genetic deficiency of the OSM receptor Oβ. We investigated its effects on cardiomyocyte apoptosis and mitochondrial biogenesis and whether Notch3/Akt signaling was involved in the regulation of OSM-induced protection against cardiac I/R injury. The mice underwent 30 min of ischemia followed by 3 h of reperfusion and were randomized to be treated with Notch3 siRNA (siNotch3) or lentivirus carrying Notch3 cDNA (Notch3) 72 h before coronary artery ligation. Myocardial infarct size, cardiac function, cardiomyocyte apoptosis and mitochondria morphology in mice that underwent cardiac I/R injury were compared between groups. OSM alleviated cardiac I/R injury by inhibiting cardiomyocyte apoptosis through promotion of Notch3 production, thus activating the PI3K/Akt pathway. OSM enhanced mitochondrial biogenesis and mitochondrial function in mice subjected to cardiac I/R injury. In contrast, OSM receptor Oβ knock out exacerbated cardiac I/R injury, decreased Notch3 production, enhanced cardiomyocyte apoptosis, and impaired mitochondrial biogenesis in cardiac I/R injured mice. The mechanism of OSM on cardiac I/R injury is partly mediated by the Notch3/Akt pathway. These results suggest a novel role of Notch3/Akt signaling that contributes to OSM-induced protection against cardiac I/R injury.

  12. The Parkinson’s Disease-Associated Protein Kinase LRRK2 Modulates Notch Signaling through the Endosomal Pathway

    PubMed Central

    Imai, Yuzuru; Kobayashi, Yoshito; Inoshita, Tsuyoshi; Meng, Hongrui; Arano, Taku; Uemura, Kengo; Asano, Takeshi; Yoshimi, Kenji; Zhang, Chang-Liang; Matsumoto, Gen; Ohtsuka, Toshiyuki; Kageyama, Ryoichiro; Kiyonari, Hiroshi; Shioi, Go; Nukina, Nobuyuki; Hattori, Nobutaka; Takahashi, Ryosuke

    2015-01-01

    Leucine-rich repeat kinase 2 (LRRK2) is a key molecule in the pathogenesis of familial and idiopathic Parkinson’s disease (PD). We have identified two novel LRRK2-associated proteins, a HECT-type ubiquitin ligase, HERC2, and an adaptor-like protein with six repeated Neuralized domains, NEURL4. LRRK2 binds to NEURL4 and HERC2 via the LRRK2 Ras of complex proteins (ROC) domain and NEURL4, respectively. HERC2 and NEURL4 link LRRK2 to the cellular vesicle transport pathway and Notch signaling, through which the LRRK2 complex promotes the recycling of the Notch ligand Delta-like 1 (Dll1)/Delta (Dl) through the modulation of endosomal trafficking. This process negatively regulates Notch signaling through cis-inhibition by stabilizing Dll1/Dl, which accelerates neural stem cell differentiation and modulates the function and survival of differentiated dopaminergic neurons. These effects are strengthened by the R1441G ROC domain-mutant of LRRK2. These findings suggest that the alteration of Notch signaling in mature neurons is a component of PD etiology linked to LRRK2. PMID:26355680

  13. The Notch Ligand Jagged1 as a Target for Anti-Tumor Therapy

    PubMed Central

    Li, Demin; Masiero, Massimo; Banham, Alison H.; Harris, Adrian L.

    2014-01-01

    The Notch pathway is increasingly attracting attention as a source of therapeutic targets for cancer. Ligand-induced Notch signaling has been implicated in various aspects of cancer biology; as a consequence, pan-Notch inhibitors and therapeutic antibodies targeting one or more of the Notch receptors have been investigated for cancer therapy. Alternatively, Notch ligands provide attractive options for therapy in cancer treatment due to their more restricted expression and better-defined functions, as well as their low rate of mutations in cancer. One of the Notch ligands, Jagged1 (JAG1), is overexpressed in many cancer types, and plays an important role in several aspects of tumor biology. In fact, JAG1-stimulated Notch activation is directly implicated in tumor growth through maintaining cancer stem cell populations, promoting cell survival, inhibiting apoptosis, and driving cell proliferation and metastasis. In addition, JAG1 can indirectly affect cancer by influencing tumor microenvironment components such as tumor vasculature and immune cell infiltration. This article gives an overview of JAG1 and its role in tumor biology, and its potential as a therapeutic target. PMID:25309874

  14. [HIF-2α/Notch3 pathway mediates CoCl2-induced migration and invasion in human breast cancer MCF-7 cells].

    PubMed

    Wang, Jian-Guo; Yuan, Lei

    2016-12-25

    The aim of this study is to investigate the effects of hypoxia inducible factor-2α (HIF-2α) and Notch3 on CoCl 2 -induced migration and invasion of human breast cancer cell line MCF-7. MCF-7 cells were exposed to normoxia (21% O 2 ) or chemical hypoxia (21% O 2 plus CoCl 2 ). Short hairpin RNA (shRNA) was used to knock down HIF-2α and Notch3 in MCF-7 cells. The mRNA expression levels of HIF-2α, Notch3 and Hey1 were measured by RT-PCR. Western blot was performed to determine the protein expression levels of HIF-2α, Notch3, Hey1, Snail and E-cadherin. CoCl 2 treatment resulted in higher protein expression levels of HIF-2α, Notch3, Hey1, Snail (P < 0.05) and lower levels of E-cadherin (P < 0.05), and promoted migration and invasion of MCF-7 cells (P < 0.05). shRNA-HIF-2α suppressed CoCl 2 -induced mRNA expression of Notch3 and Hey1. Notch3 knockdown down-regulated Snail and up-regulated E-cadherin at protein level under simulated hypoxia (P < 0.05), and inhibited CoCl 2 -induced migration and invasion of MCF-7 cells (P < 0.05). In conclusion, our data provide evidence that HIF-2α may promote the migration and invasion of MCF-7 cells under chemical hypoxic conditions by potentiating Notch3 pathway.

  15. Notch3 Signaling-Mediated Melanoma-Endothelial Crosstalk Regulates Melanoma Stem-Like Cell Homeostasis and Niche Morphogenesis

    PubMed Central

    Hsu, Mei-Yu; Yang, Moon Hee; Schnegg, Caroline I.; Hwang, Soonyean; Ryu, Byungwoo; Alani, Rhoda M.

    2016-01-01

    Melanoma is among the most virulent cancers, owing to its propensity to metastasize and its resistance to current therapies. The treatment failure is largely attributed to tumor heterogeneity, particularly subpopulations possessing stem cell-like properties, i.e., melanoma stem-like cells (MSLCs). Evidence indicates that the MSLC phenotype is malleable and may be acquired by non-MSLCs through phenotypic switching upon appropriate stimuli, the so–called “dynamic stemness”. Since the phenotypic characteristics and functional integrity of MSLCs depend on their vascular niche, using a two dimensional (2D) melanoma-endothelium co-culture model, where the MSLC niche is recapitulated in vitro, we identified Notch3 signaling pathway as a micro-environmental cue governing MSLC phenotypic plasticity via pathway-specific gene expression arrays. Accordingly, lentiviral shRNA-mediated Notch3 knockdown (KD) in melanoma cell lines exhibiting high levels of endogenous Notch3 led to retarded/abolished tumorigenicity in vivo through both depleting MSLC fractions, evinced by MSLC marker down-regulation (e.g., CD133 and CD271); and impeding the MSLC niche, corroborated by the attenuated tumor angiogenesis as well as vasculogenic mimicry. In contrast, Notch3 KD affected neither tumor growth nor MSLC subsets in a melanoma cell line with relatively low endogenous Notch3 expression. Thus, Notch3 signaling may facilitate MSLC plasticity and niche morphogenesis in a cell context-dependent fashion. Our findings illustrate Notch3 as a molecular switch driving melanoma heterogeneity, and provide the biological rationale for Notch inhibition as a promising therapeutic option. PMID:28165469

  16. Molecular Pathways: Translational and Therapeutic Implications of the Notch Signaling Pathway in Cancer

    PubMed Central

    Previs, Rebecca A.; Coleman, Robert L.; Harris, Adrian L.; Sood, Anil K.

    2014-01-01

    Over 100 years have passed since the first observation of the notched wing phenotype in Drosophila melanogaster, and significant progress has been made to characterize the role of the Notch receptor, its ligands, downstream targets, and crosstalk with other signaling pathways. The canonical Notch pathway with four Notch receptors (Notch1-4) and five ligands (DLL1, 3–4, Jagged 1–2) is an evolutionarily conserved cell signaling pathway that plays critical roles in cell-fate determination, differentiation, development, tissue patterning, cell proliferation, and death. In cancer, these roles have a critical impact on tumor behavior and response to therapy. Since the role of Notch remains tissue and context dependent, alterations within this pathway may lead to tumor suppressive or oncogenic phenotypes. Although no FDA approved therapies currently exist for the Notch pathway, multiple therapeutics (e.g., demcizumab, tarextumab, GSI MK0752, R04929097, and PF63084014) have been developed to target different aspects of this pathway for both hematologic and solid malignancies. Understanding the context-specific effects of the Notch pathway will be important for individualized therapies targeting this pathway. PMID:25388163

  17. Upregulation of ASCL1 and inhibition of Notch signaling pathway characterize progressive astrocytoma.

    PubMed

    Somasundaram, Kumaravel; Reddy, Sreekanth P; Vinnakota, Katyayni; Britto, Ramona; Subbarayan, Madhavan; Nambiar, Sandeep; Hebbar, Aparna; Samuel, Cini; Shetty, Mitesh; Sreepathi, Hari Kishore; Santosh, Vani; Hegde, Alangar Sathyaranjandas; Hegde, Sridevi; Kondaiah, Paturu; Rao, M R S

    2005-10-27

    Astrocytoma is the most common type of brain cancer constituting more than half of all brain tumors. With an aim to identify markers describing astrocytoma progression, we have carried out microarray analysis of astrocytoma samples of different grades using cDNA microarray containing 1152 cancer-specific genes. Data analysis identified several differentially regulated genes between normal brain tissue and astrocytoma as well as between grades II/III astrocytoma and glioblastoma multiforme (GBM; grade IV). We found several genes known to be involved in malignancy including Achaete-scute complex-like 1 (Drosophila) (ASCL1; Hash 1). As ASCL has been implicated in neuroendocrine, medullary thyroid and small-cell lung cancers, we chose to examine the role of ASCL1 in the astrocytoma development. Our data revealed that ASCL1 is overexpressed in progressive astrocytoma as evidenced by increased levels of ASCL1 transcripts in 85.71% (6/7) of grade II diffuse astrocytoma (DA), 90% (9/10) of grade III anaplastic astrocytoma (AA) and 87.5% (7/8) of secondary GBMs, while the majority of primary de novo GBMs expressed similar to or less than normal brain levels (66.67%; 8/12). ASCL1 upregulation in progressive astrocytoma is accompanied by inhibition of Notch signaling as seen by uninduced levels of HES1, a transcriptional target of Notch1, increased levels of HES6, a dominant-negative inhibitor of HES1-mediated repression of ASCL1, and increased levels of Notch ligand Delta1, which is capable of inhibiting Notch signaling by forming intracellular Notch ligand autonomous complexes. Our results imply that inhibition of Notch signaling may be an important early event in the development of grade II DA and subsequent progression to grade III AA and secondary GBM. Furthermore, ASCL1 appears to be a putative marker to distinguish primary GBM from secondary GBM.

  18. Notch signalling mediates reproductive constraint in the adult worker honeybee

    PubMed Central

    Duncan, Elizabeth J.; Hyink, Otto; Dearden, Peter K.

    2016-01-01

    The hallmark of eusociality is the reproductive division of labour, in which one female caste reproduces, while reproduction is constrained in the subordinate caste. In adult worker honeybees (Apis mellifera) reproductive constraint is conditional: in the absence of the queen and brood, adult worker honeybees activate their ovaries and lay haploid male eggs. Here, we demonstrate that chemical inhibition of Notch signalling can overcome the repressive effect of queen pheromone and promote ovary activity in adult worker honeybees. We show that Notch signalling acts on the earliest stages of oogenesis and that the removal of the queen corresponds with a loss of Notch protein in the germarium. We conclude that the ancient and pleiotropic Notch signalling pathway has been co-opted into constraining reproduction in worker honeybees and we provide the first molecular mechanism directly linking ovary activity in adult worker bees with the presence of the queen. PMID:27485026

  19. Microbiota promote secretory cell determination in the intestinal epithelium by modulating host Notch signaling.

    PubMed

    Troll, Joshua V; Hamilton, M Kristina; Abel, Melissa L; Ganz, Julia; Bates, Jennifer M; Stephens, W Zac; Melancon, Ellie; van der Vaart, Michiel; Meijer, Annemarie H; Distel, Martin; Eisen, Judith S; Guillemin, Karen

    2018-02-23

    Resident microbes promote many aspects of host development, although the mechanisms by which microbiota influence host tissues remain unclear. We showed previously that the microbiota is required for allocation of appropriate numbers of secretory cells in the zebrafish intestinal epithelium. Because Notch signaling is crucial for secretory fate determination, we conducted epistasis experiments to establish whether the microbiota modulates host Notch signaling. We also investigated whether innate immune signaling transduces microbiota cues via the Myd88 adaptor protein. We provide the first evidence that microbiota-induced, Myd88-dependent signaling inhibits host Notch signaling in the intestinal epithelium, thereby promoting secretory cell fate determination. These results connect microbiota activity via innate immune signaling to the Notch pathway, which also plays crucial roles in intestinal homeostasis throughout life and when impaired can result in chronic inflammation and cancer. © 2018. Published by The Company of Biologists Ltd.

  20. The Hippo signaling functions through the Notch signaling to regulate intrahepatic bile duct development in mammals.

    PubMed

    Wu, Nan; Nguyen, Quy; Wan, Ying; Zhou, Tiaohao; Venter, Julie; Frampton, Gabriel A; DeMorrow, Sharon; Pan, Duojia; Meng, Fanyin; Glaser, Shannon; Alpini, Gianfranco; Bai, Haibo

    2017-07-01

    The Hippo signaling pathway and the Notch signaling pathway are evolutionary conserved signaling cascades that have important roles in embryonic development of many organs. In murine liver, disruption of either pathway impairs intrahepatic bile duct development. Recent studies suggested that the Notch signaling receptor Notch2 is a direct transcriptional target of the Hippo signaling pathway effector YAP, and the Notch signaling is a major mediator of the Hippo signaling in maintaining biliary cell characteristics in adult mice. However, it remains to be determined whether the Hippo signaling pathway functions through the Notch signaling in intrahepatic bile duct development. We found that loss of the Hippo signaling pathway tumor suppressor Nf2 resulted in increased expression levels of the Notch signaling pathway receptor Notch2 in cholangiocytes but not in hepatocytes. When knocking down Notch2 on the background of Nf2 deficiency in mouse livers, the excessive bile duct development induced by Nf2 deficiency was suppressed by heterozygous and homozygous deletion of Notch2 in a dose-dependent manner. These results implicated that Notch signaling is one of the downstream effectors of the Hippo signaling pathway in regulating intrahepatic bile duct development.

  1. The Hippo signaling functions through the Notch signaling to regulate intrahepatic bile duct development in mammals

    PubMed Central

    Wu, Nan; Nguyen, Quy; Wan, Ying; Zhou, Tiaohao; Venter, Julie; Frampton, Gabriel A; DeMorrow, Sharon; Pan, Duojia; Meng, Fanyin; Glaser, Shannon; Alpini, Gianfranco; Bai, Haibo

    2018-01-01

    The Hippo signaling pathway and the Notch signaling pathway are evolutionary conserved signaling cascades that have important roles in embryonic development of many organs. In murine liver, disruption of either pathway impairs intrahepatic bile duct development. Recent studies suggested that the Notch signaling receptor Notch2 is a direct transcriptional target of the Hippo signaling pathway effector YAP, and the Notch signaling is a major mediator of the Hippo signaling in maintaining biliary cell characteristics in adult mice. However, it remains to be determined whether the Hippo signaling pathway functions through the Notch signaling in intrahepatic bile duct development. We found that loss of the Hippo signaling pathway tumor suppressor Nf2 resulted in increased expression levels of the Notch signaling pathway receptor Notch2 in cholangiocytes but not in hepatocytes. When knocking down Notch2 on the background of Nf2 deficiency in mouse livers, the excessive bile duct development induced by Nf2 deficiency was suppressed by heterozygous and homozygous deletion of Notch2 in a dose-dependent manner. These results implicated that Notch signaling is one of the downstream effectors of the Hippo signaling pathway in regulating intrahepatic bile duct development. PMID:28581486

  2. A Synthetic Triterpenoid CDDO-Im Inhibits Tumorsphere Formation by Regulating Stem Cell Signaling Pathways in Triple-Negative Breast Cancer

    PubMed Central

    Wahler, Joseph; Liby, Karen T.; Sporn, Michael B.; Suh, Nanjoo

    2014-01-01

    Triple-negative breast cancer is associated with poor prognosis because of a high rate of tumor recurrence and metastasis. Previous studies demonstrated that the synthetic triterpenoid, CDDO-Imidazolide (CDDO-Im) induced cell cycle arrest and apoptosis in triple-negative breast cancer. Since a small subpopulation of cancer stem cells has been suggested to be responsible for drug resistance and metastasis of tumors, our present study determined whether the effects of CDDO-Im in triple-negative breast cancer are due to the inhibition of a cancer stem cell subpopulation. CDDO-Im treatment markedly induced cell cycle arrest at G2/M-phase and apoptosis in the triple-negative breast cancer cell lines, SUM159 and MDA-MB-231. Because SUM159 cells were more sensitive to CDDO-Im than MDA-MB-231 cells, the effects of CDDO-Im on the cancer stem cell subpopulation were further investigated in SUM159 cells. SUM159 cells formed tumorspheres in culture, and the cancer stem cell subpopulation, CD24−/EpCAM+ cells, was markedly enriched in SUM159 tumorspheres. The CD24−/EpCAM+ cells in SUM159 tumorspheres were significantly inhibited by CDDO-Im treatment. CDDO-Im also significantly decreased sphere forming efficiency and tumorsphere size in both primary and secondary sphere cultures. PCR array of stem cell signaling genes showed that expression levels of many key molecules in the stem cell signaling pathways, such as Notch, TGF-β/Smad, Hedgehog and Wnt, were significantly down-regulated by CDDO-Im in SUM159 tumorspheres. Protein levels of Notch receptors (c-Notch1, Notch1 and Notch3), TGF-β/Smad (pSmad2/3) and Hedgehog downstream effectors (GLI1) also were markedly reduced by CDDO-Im. In conclusion, the present study demonstrates that the synthetic triterpenoid, CDDO-Im, is a potent anti-cancer agent against triple-negative breast cancer cells by targeting the cancer stem cell subpopulation. PMID:25229616

  3. AMPK Is Essential to Balance Glycolysis and Mitochondrial Metabolism to Control T-ALL Cell Stress and Survival.

    PubMed

    Kishton, Rigel J; Barnes, Carson E; Nichols, Amanda G; Cohen, Sivan; Gerriets, Valerie A; Siska, Peter J; Macintyre, Andrew N; Goraksha-Hicks, Pankuri; de Cubas, Aguirre A; Liu, Tingyu; Warmoes, Marc O; Abel, E Dale; Yeoh, Allen Eng Juh; Gershon, Timothy R; Rathmell, W Kimryn; Richards, Kristy L; Locasale, Jason W; Rathmell, Jeffrey C

    2016-04-12

    T cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy associated with Notch pathway mutations. While both normal activated and leukemic T cells can utilize aerobic glycolysis to support proliferation, it is unclear to what extent these cell populations are metabolically similar and if differences reveal T-ALL vulnerabilities. Here we show that aerobic glycolysis is surprisingly less active in T-ALL cells than proliferating normal T cells and that T-ALL cells are metabolically distinct. Oncogenic Notch promoted glycolysis but also induced metabolic stress that activated 5' AMP-activated kinase (AMPK). Unlike stimulated T cells, AMPK actively restrained aerobic glycolysis in T-ALL cells through inhibition of mTORC1 while promoting oxidative metabolism and mitochondrial Complex I activity. Importantly, AMPK deficiency or inhibition of Complex I led to T-ALL cell death and reduced disease burden. Thus, AMPK simultaneously inhibits anabolic growth signaling and is essential to promote mitochondrial pathways that mitigate metabolic stress and apoptosis in T-ALL. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Developmental patterning of the cardiac atrioventricular canal by Notch and Hairy-related transcription factors

    PubMed Central

    Rutenberg, Joshua B.; Fischer, Andreas; Jia, Haibo; Gessler, Manfred; Zhong, Tao P.; Mercola, Mark

    2013-01-01

    Mutations in Notch2, Jagged1 or homologs of the Hairy-related transcriptional repressor Hey2 cause congenital malformations involving the non-chamber atrioventricular canal (AVC) and inner curvature (IC) regions of the heart, but the underlying mechanisms have not been investigated. By manipulating signaling directly within the developing chick heart, we demonstrated that Notch2, Hey1 and Hey2 initiate a signaling cascade that delimits the non-chamber AVC and IC regions. Specifically, misactivation of Notch2 signaling, or misexpression of either Hey1 or Hey2, repressed Bmp2. Because Jagged (also known as Serrate in non-mammalian species) ligands were found to be present in prospective chamber myocardium, these data support the model that Notch2 and Hey proteins cause the progressive restriction of Bmp2 expression to within the developing AVC and IC, where it is essential for differentiation. Misactivation or inhibition of Notch2 specifically induced or inhibited Hey1, respectively, but these manipulations did not affect Hey2, implicating Hey1 as the direct mediator of Notch2. Bmp2 within the developing AVC and IC has been shown to induce Tbx2, and we found that Tbx2 misexpression inhibited the expression of both Hey1 and Hey2. Tbx2, therefore, is envisaged to constitute a feedback loop that sharpens the border with the developing AVC and IC by delimiting Hey gene expression to within prospective chamber regions. Analysis of the loss-of-function phenotype in mouse embryos homozygous for targeted disruption of Hey2 revealed an expanded AVC domain of Bmp2. Similarly, zebrafish gridlock (Hey2 homolog) mutant embryos showed ectopic expression of Bmp4, which normally marks AVC myocardium in this species. Thus, Hey pathway regulation of cardiac Bmp appears to be an evolutionarily conserved mechanism to delimit AVC and IC fate, and provides a potential mechanistic explanation for cardiac malformations caused by mutations in Serrate/Jagged1 and Notch signaling components. PMID:17021042

  5. Glycogen synthase kinase-3 inhibitor AR-A014418 suppresses pancreatic cancer cell growth via inhibition of GSK-3-mediated Notch1 expression.

    PubMed

    Kunnimalaiyaan, Selvi; Gamblin, T Clark; Kunnimalaiyaan, Muthusamy

    2015-09-01

    Glycogen synthase kinase-3 (GSK-3) can act as either a tumour promoter or suppressor by its inactivation depending on the cell type. There are conflicting reports on the roles of GSK-3 isoforms and their interaction with Notch1 in pancreatic cancer. It was hypothesized that GSK-3α stabilized Notch1 in pancreatic cancer cells thereby promoting cellular proliferation. The pancreatic cancer cell lines MiaPaCa2, PANC-1 and BxPC-3, were treated with 0-20 μM of AR-A014418 (AR), a known GSK-3 inhibitor. Cell viability was determined by the MTT assay and Live-Cell Imaging. The levels of Notch pathway members (Notch1, HES-1, survivin and cyclinD1), phosphorylated GSK-3 isoforms, and apoptotic markers were determined by Western blot. Immunoprecipitation was performed to identify the binding of GSK-3 specific isoform to Notch1. AR-A014418 treatment had a significant dose-dependent growth reduction (P < 0.001) in pancreatic cancer cells compared with the control and the cytotoxic effect is as a result of apoptosis. Importantly, a reduction in GSK-3 phosphorylation lead to a reduction in Notch pathway members. Overexpression of active Notch1 in AR-A014418-treated cells resulted in the negation of growth suppression. Immunoprecipitation analysis revealed that GSK-3α binds to Notch1. This study demonstrates for the first time that the growth suppressive effect of AR-A014418 on pancreatic cancer cells is mainly mediated by a reduction in phosphorylation of GSK-3α with concomitant Notch1 reduction. GSK-3α appears to stabilize Notch1 by binding and may represent a target for therapeutic development. Furthermore, downregulation of GSK-3 and Notch1 may be a viable strategy for possible chemosensitization of pancreatic cancer cells to standard therapeutics. © 2015 International Hepato-Pancreato-Biliary Association.

  6. miR-935 suppresses gastric signet ring cell carcinoma tumorigenesis by targeting Notch1 expression

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yan, Chao; Yu, Jianchun, E-mail: yu_jchpumch@163.com; Kang, Weiming

    Gastric signet ring cell carcinoma (GSRCC) is a unique pathological type of gastric carcinoma that is extremely invasive and has a poor prognosis. Expression of microRNAs (miRNAs) has been closely linked to the carcinogenesis of gastric cancer and has been considered as a powerful prognostic marker. The function of miR-935 has never been reported in cancer before. We found, using microRNA array, that expression of miR-935 in GSRCC cell lines is lower than in non-GSRCC cell lines, and enhanced expression of miR-935 in GSRCC cell-lines inhibit cell proliferation, migration and invasion. We also identified Notch1 as a direct target ofmore » miR-935. Knockdown of Notch1 reduced proliferation, migration/invasion of GSRCC cells, and overexpression Notch1's activated form (Notch intracellular domain) could rescue miR-935's tumor suppressive effect on GSRCC. Expression of miR-935 was lower in gastric carcinoma tissue than in paired normal tissue samples, and lower in GSRCC than in non-GSRCC. Our results demonstrate the inverse correlation between the expression of miR-935 and Notch1 in gastric tissues. We conclude that miR-935 inhibits gastric carcinoma cell proliferation, migration and invasion by targeting Notch1, suggesting potential applications of the miR-935-Notch1 pathway in gastric cancer clinical diagnosis and therapeutics, especially in gastric signet ring cell carcinoma. - Highlights: • The expression of miR-935 is lower in GC tissue than in paired normal tissue. • The expression of miR-935 is lower in GSRCC tissue than in non-GSRCC. • Enhanced expression of miR-935 suppresses tumorigenesis of GSRCC. • Notch1 is a direct target of miR-935.« less

  7. Notch signaling inhibits hepatocellular carcinoma following inactivation of the RB pathway

    PubMed Central

    Viatour, Patrick; Ehmer, Ursula; Saddic, Louis A.; Dorrell, Craig; Andersen, Jesper B.; Lin, Chenwei; Zmoos, Anne-Flore; Mazur, Pawel K.; Schaffer, Bethany E.; Ostermeier, Austin; Vogel, Hannes; Sylvester, Karl G.; Thorgeirsson, Snorri S.; Grompe, Markus

    2011-01-01

    Hepatocellular carcinoma (HCC) is the third cancer killer worldwide with >600,000 deaths every year. Although the major risk factors are known, therapeutic options in patients remain limited in part because of our incomplete understanding of the cellular and molecular mechanisms influencing HCC development. Evidence indicates that the retinoblastoma (RB) pathway is functionally inactivated in most cases of HCC by genetic, epigenetic, and/or viral mechanisms. To investigate the functional relevance of this observation, we inactivated the RB pathway in the liver of adult mice by deleting the three members of the Rb (Rb1) gene family: Rb, p107, and p130. Rb family triple knockout mice develop liver tumors with histopathological features and gene expression profiles similar to human HCC. In this mouse model, cancer initiation is associated with the specific expansion of populations of liver stem/progenitor cells, indicating that the RB pathway may prevent HCC development by maintaining the quiescence of adult liver progenitor cells. In addition, we show that during tumor progression, activation of the Notch pathway via E2F transcription factors serves as a negative feedback mechanism to slow HCC growth. The level of Notch activity is also able to predict survival of HCC patients, suggesting novel means to diagnose and treat HCC. PMID:21875955

  8. An endothelial cell niche induces hepatic specification through dual repression of Wnt and Notch signaling

    PubMed Central

    Han, Songyan; Dziedzic, Noelle; Gadue, Paul; Keller, Gordon M.; Gouon-Evans, Valerie

    2012-01-01

    Complex cross-talk between endoderm and the microenvironment is an absolute requirement to orchestrate hepatic specification and expansion. In the mouse, the septum transversum and cardiac mesoderm, through secreted BMPs and FGFs, respectively, instruct the adjacent ventral endoderm to become hepatic endoderm. Consecutively, endothelial cells promote expansion of the specified hepatic endoderm. Using a mouse reporter embryonic stem (ES) cell line in which hCD4 and hCD25 were targeted to the Foxa2 and Foxa3 loci, we reconstituted an in vitro culture system in which committed endoderm cells co-expressing hCD4-Foxa2 and hCD25-Foxa3 were isolated, and co-cultured with endothelial cells in the presence of BMP4 and bFGF. In this culture setting, we provide mechanistic evidence that endothelial cells function not only to promote hepatic endoderm expansion, but are also required at an earlier step for hepatic specification, at least in part through regulation of the Wnt and Notch pathways. Activation of Wnt and Notch by chemical or genetic approaches increases endoderm cell numbers but inhibits hepatic specification, and conversely, chemical inhibition of both pathways enhances hepatic specification and reduces proliferation. Using identical co-culture conditions, we defined a similar dependence of endoderm harvested from embryos on endothelial cells to support their growth and hepatic specification. Our findings (1) confirm a conserved role of Wnt repression for mouse hepatic specification, (2) uncover a novel role for Notch repression in the hepatic fate decision, and (3) demonstrate that repression of Wnt and Notch signaling in hepatic endoderm is controlled by the endothelial cell niche. PMID:21732480

  9. Operating principles of Notch-Delta-Jagged module of cell-cell communication

    NASA Astrophysics Data System (ADS)

    Jolly, Mohit Kumar; Boareto, Marcelo; Lu, Mingyang; Onuchic, Jose' N.; Clementi, Cecilia; Ben-Jacob, Eshel

    2015-05-01

    Notch pathway is an evolutionarily conserved cell-cell communication mechanism governing cell-fate during development and tumor progression. It is activated when Notch receptor of one cell binds to either of its ligand—Delta or Jagged—of another cell. Notch-Delta (ND) signaling forms a two-way switch, and two cells interacting via ND signaling adopt different fates—Sender (high ligand, low receptor) and Receiver (low ligand, high receptor). Notch-Delta-Jagged signaling (NDJ) behaves as a three-way switch and enables an additional fate—hybrid Sender/Receiver (S/R) (medium ligand, medium receptor). Here, by extending our framework of NDJ signaling for a two-cell system, we show that higher production rate of Jagged, but not that of Delta, expands the range of parameters for which both cells attain the hybrid S/R state. Conversely, glycosyltransferase Fringe and cis-inhibition reduces this range of conditions, and reduces the relative stability of the hybrid S/R state, thereby promoting cell-fate divergence and consequently lateral inhibition-based patterns. Lastly, soluble Jagged drives the cells to attain the hybrid S/R state, and soluble Delta drives them to be Receivers. We also discuss the critical role of hybrid S/R state in promoting cancer metastasis by enabling collective cell migration and expanding cancer stem cell (CSC) population.

  10. CpG in Combination with an Inhibitor of Notch Signaling Suppresses Formalin-Inactivated Respiratory Syncytial Virus-Enhanced Airway Hyperresponsiveness and Inflammation by Inhibiting Th17 Memory Responses and Promoting Tissue-Resident Memory Cells in Lungs.

    PubMed

    Zhang, Lei; Li, Hongyong; Hai, Yan; Yin, Wei; Li, Wenjian; Zheng, Boyang; Du, Xiaomin; Li, Na; Zhang, Zhengzheng; Deng, Yuqing; Zeng, Ruihong; Wei, Lin

    2017-05-15

    Respiratory syncytial virus (RSV) is the leading cause of childhood hospitalizations. The formalin-inactivated RSV (FI-RSV) vaccine-enhanced respiratory disease (ERD) has been an obstacle to the development of a safe and effective killed RSV vaccine. Agonists of Toll-like receptor (TLR) have been shown to regulate immune responses induced by FI-RSV. Notch signaling plays critical roles during the differentiation and effector function phases of innate and adaptive immune responses. Cross talk between TLR and Notch signaling pathways results in fine-tuning of TLR-triggered innate inflammatory responses. We evaluated the impact of TLR and Notch signaling on ERD in a murine model by administering CpG, an agonist of TLR9, in combination with L685,458, an inhibitor of Notch signaling during FI-RSV immunization. Activation with CpG or deficiency of MyD88-dependent TLR signaling did not alleviate airway inflammation in FI-RSV-immunized mice. Activation or inhibition of Notch signaling with Dll4, one of the Notch ligands, or L685,458 did not suppress FI-RSV-enhanced airway inflammation either. However, the CpG together with L685,458 markedly inhibited FI-RSV-enhanced airway hyperresponsiveness, weight loss, and lung inflammation. Interestingly, CpG plus L685,458 completely inhibited FI-RSV-associated Th17 and Th17-associated proinflammatory chemokine responses in lungs following RSV challenge but not Th1 or Th2, memory responses. In addition, FI-RSV plus CpG plus L685,458 promoted protective CD8 + lung tissue-resident memory (TRM) cells. These results indicate that activation of TLR signaling combined with inhibition of Notch signaling prevent FI-RSV ERD, and the mechanism appears to involve suppressing proinflammatory Th17 memory responses and promoting protective TRM in lungs. IMPORTANCE RSV is the most important cause of lower respiratory tract infections in infants. The FI-RSV-enhanced respiratory disease (ERD) is a major impediment to the development of a safe and effective killed RSV vaccine. Using adjuvants to regulate innate and adaptive immune responses could be an effective method to prevent ERD. We evaluated the impact of TLR and Notch signaling on ERD by administering CpG, an agonist of TLR9, in combination with L685,458, an inhibitor of Notch signaling, during FI-RSV immunization. The data showed that treatment of TLR or Notch signaling alone did not suppress FI-RSV-enhanced airway inflammation, while CpG plus L685,458 markedly inhibited ERD. The mechanism appears to involve suppressing Th17 memory responses and promoting tissue-resident memory cells. Moreover, these results suggest that regulation of lung immune memory with adjuvant compounds containing more than one immune-stimulatory molecule may be a good strategy to prevent FI-RSV ERD. Copyright © 2017 American Society for Microbiology.

  11. CpG in Combination with an Inhibitor of Notch Signaling Suppresses Formalin-Inactivated Respiratory Syncytial Virus-Enhanced Airway Hyperresponsiveness and Inflammation by Inhibiting Th17 Memory Responses and Promoting Tissue-Resident Memory Cells in Lungs

    PubMed Central

    Zhang, Lei; Li, Hongyong; Hai, Yan; Yin, Wei; Li, Wenjian; Zheng, Boyang; Du, Xiaomin; Li, Na; Zhang, Zhengzheng; Deng, Yuqing

    2017-01-01

    ABSTRACT Respiratory syncytial virus (RSV) is the leading cause of childhood hospitalizations. The formalin-inactivated RSV (FI-RSV) vaccine-enhanced respiratory disease (ERD) has been an obstacle to the development of a safe and effective killed RSV vaccine. Agonists of Toll-like receptor (TLR) have been shown to regulate immune responses induced by FI-RSV. Notch signaling plays critical roles during the differentiation and effector function phases of innate and adaptive immune responses. Cross talk between TLR and Notch signaling pathways results in fine-tuning of TLR-triggered innate inflammatory responses. We evaluated the impact of TLR and Notch signaling on ERD in a murine model by administering CpG, an agonist of TLR9, in combination with L685,458, an inhibitor of Notch signaling during FI-RSV immunization. Activation with CpG or deficiency of MyD88-dependent TLR signaling did not alleviate airway inflammation in FI-RSV-immunized mice. Activation or inhibition of Notch signaling with Dll4, one of the Notch ligands, or L685,458 did not suppress FI-RSV-enhanced airway inflammation either. However, the CpG together with L685,458 markedly inhibited FI-RSV-enhanced airway hyperresponsiveness, weight loss, and lung inflammation. Interestingly, CpG plus L685,458 completely inhibited FI-RSV-associated Th17 and Th17-associated proinflammatory chemokine responses in lungs following RSV challenge but not Th1 or Th2, memory responses. In addition, FI-RSV plus CpG plus L685,458 promoted protective CD8+ lung tissue-resident memory (TRM) cells. These results indicate that activation of TLR signaling combined with inhibition of Notch signaling prevent FI-RSV ERD, and the mechanism appears to involve suppressing proinflammatory Th17 memory responses and promoting protective TRM in lungs. IMPORTANCE RSV is the most important cause of lower respiratory tract infections in infants. The FI-RSV-enhanced respiratory disease (ERD) is a major impediment to the development of a safe and effective killed RSV vaccine. Using adjuvants to regulate innate and adaptive immune responses could be an effective method to prevent ERD. We evaluated the impact of TLR and Notch signaling on ERD by administering CpG, an agonist of TLR9, in combination with L685,458, an inhibitor of Notch signaling, during FI-RSV immunization. The data showed that treatment of TLR or Notch signaling alone did not suppress FI-RSV-enhanced airway inflammation, while CpG plus L685,458 markedly inhibited ERD. The mechanism appears to involve suppressing Th17 memory responses and promoting tissue-resident memory cells. Moreover, these results suggest that regulation of lung immune memory with adjuvant compounds containing more than one immune-stimulatory molecule may be a good strategy to prevent FI-RSV ERD. PMID:28275186

  12. Low Oxygen Modulates Multiple Signaling Pathways, Increasing Self-Renewal, While Decreasing Differentiation, Senescence, and Apoptosis in Stromal MIAMI Cells

    PubMed Central

    Rios, Carmen; D'Ippolito, Gianluca; Curtis, Kevin M.; Delcroix, Gaëtan J.-R.; Gomez, Lourdes A.; El Hokayem, Jimmy; Rieger, Megan; Parrondo, Ricardo; de las Pozas, Alicia; Perez-Stable, Carlos; Howard, Guy A.

    2016-01-01

    Human bone marrow multipotent mesenchymal stromal cell (hMSC) number decreases with aging. Subpopulations of hMSCs can differentiate into cells found in bone, vasculature, cartilage, gut, and other tissues and participate in their repair. Maintaining throughout adult life such cell subpopulations should help prevent or delay the onset of age-related degenerative conditions. Low oxygen tension, the physiological environment in progenitor cell-rich regions of the bone marrow microarchitecture, stimulates the self-renewal of marrow-isolated adult multilineage inducible (MIAMI) cells and expression of Sox2, Nanog, Oct4a nuclear accumulation, Notch intracellular domain, notch target genes, neuronal transcriptional repressor element 1 (RE1)-silencing transcription factor (REST), and hypoxia-inducible factor-1 alpha (HIF-1α), and additionally, by decreasing the expression of (i) the proapoptotic proteins, apoptosis-inducing factor (AIF) and Bak, and (ii) senescence-associated p53 expression and β-galactosidase activity. Furthermore, low oxygen increases canonical Wnt pathway signaling coreceptor Lrp5 expression, and PI3K/Akt pathway activation. Lrp5 inhibition decreases self-renewal marker Sox2 mRNA, Oct4a nuclear accumulation, and cell numbers. Wortmannin-mediated PI3K/Akt pathway inhibition leads to increased osteoblastic differentiation at both low and high oxygen tension. We demonstrate that low oxygen stimulates a complex signaling network involving PI3K/Akt, Notch, and canonical Wnt pathways, which mediate the observed increase in nuclear Oct4a and REST, with simultaneous decrease in p53, AIF, and Bak. Collectively, these pathway activations contribute to increased self-renewal with concomitant decreased differentiation, cell cycle arrest, apoptosis, and/or senescence in MIAMI cells. Importantly, the PI3K/Akt pathway plays a central mechanistic role in the oxygen tension-regulated self-renewal versus osteoblastic differentiation of progenitor cells. PMID:27059084

  13. LncRNA-LET inhibits cell viability, migration and EMT while induces apoptosis by up-regulation of TIMP2 in human granulosa-like tumor cell line KGN.

    PubMed

    Han, Qingfang; Zhang, Wenke; Meng, Jinlai; Ma, Li; Li, Aihua

    2018-04-01

    Polycystic ovary syndrome (PCOS) is a common endocrine disease characterized by hyperandrogenism, irregular menses, and polycystic ovaries. Several long non-coding RNAs (lncRNAs) are aberrantly expressed in PCOS patients; however, little is known about the effects of the lncRNA-low expression in tumor (lncRNA-LET) on PCOS. We aimed to explore the effects of lncRNA-LET on human granulosa-like tumor cell line, KGN. Expression of lncRNA-LET in normal IOSE80 cells and granulosa cells was determined by qRT-PCR. KGN cell viability, apoptosis and migration were measured by trypan blue exclusion method, flow cytometry assay and wound healing assay, respectively. TGF-β1 was used to induce epithelial-mesenchymal transition (EMT) process. LncRNA-LET expression and mRNA expressions of TIMP2 and EMT-related proteins were measured by qRT-PCR. Western blot analysis was used to measure the protein expression of apoptosis-related proteins, EMT-related proteins, TIMP2, and the proteins in the Wnt/β-catenin and Notch signaling pathways. lncRNA-LET was down-regulated in KGN cells, and its overexpression inhibited cell viability and migration, and promoted apoptosis in KGN cells. Overexpression of lncRNA-LET increased the expression of E-cadherin and decreased the expressions of N-cadherin and vimentin in KGN cells. These effects of lncRNA-LET on KGN cells were reversed by TIMP2 suppression. Overexpression of TIMP2 inhibited cell viability, migration and EMT process, and increased apoptosis by activating the Wnt/β-catenin and Notch pathways. Overexpression of lncRNA-LET inhibits cell viability, migration and EMT process, and increases apoptosis in KGN cells by up-regulating the expression of TIMP2 and activating the Wnt/β-catenin and notch signaling pathways. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  14. Dll4 Blockade Potentiates the Anti-Tumor Effects of VEGF Inhibition in Renal Cell Carcinoma Patient-Derived Xenografts

    PubMed Central

    Miles, Kiersten Marie; Seshadri, Mukund; Ciamporcero, Eric; Adelaiye, Remi; Gillard, Bryan; Sotomayor, Paula; Attwood, Kristopher; Shen, Li; Conroy, Dylan; Kuhnert, Frank; Lalani, Alshad S.; Thurston, Gavin; Pili, Roberto

    2014-01-01

    Background The Notch ligand Delta-like 4 (Dll4) is highly expressed in vascular endothelium and has been shown to play a pivotal role in regulating tumor angiogenesis. Blockade of the Dll4-Notch pathway in preclinical cancer models has been associated with non-productive angiogenesis and reduced tumor growth. Given the cross-talk between the vascular endothelial growth factor (VEGF) and Delta-Notch pathways in tumor angiogenesis, we examined the activity of a function-blocking Dll4 antibody, REGN1035, alone and in combination with anti-VEGF therapy in renal cell carcinoma (RCC). Methods and Results Severe combined immunodeficiency (SCID) mice bearing patient-derived clear cell RCC xenografts were treated with REGN1035 and in combination with the multi-targeted tyrosine kinase inhibitor sunitinib or the VEGF blocker ziv-aflibercept. Immunohistochemical and immunofluorescent analyses were carried out, as well as magnetic resonance imaging (MRI) examinations pre and 24 hours and 2 weeks post treatment. Single agent treatment with REGN1035 resulted in significant tumor growth inhibition (36–62%) that was equivalent to or exceeded the single agent anti-tumor activity of the VEGF pathway inhibitors sunitinib (38–54%) and ziv-aflibercept (46%). Importantly, combination treatments with REGN1035 plus VEGF inhibitors resulted in enhanced anti-tumor effects (72–80% growth inhibition), including some tumor regression. Magnetic resonance imaging showed a marked decrease in tumor perfusion in all treatment groups. Interestingly, anti-tumor efficacy of the combination of REGN1035 and ziv-aflibercept was also observed in a sunitinib resistant ccRCC model. Conclusions Overall, these findings demonstrate the potent anti-tumor activity of Dll4 blockade in RCC patient-derived tumors and a combination benefit for the simultaneous targeting of the Dll4 and VEGF signaling pathways, highlighting the therapeutic potential of this treatment modality in RCC. PMID:25393540

  15. Could Notch signaling pathway be a potential therapeutic option in renal diseases?

    PubMed

    Marquez-Exposito, Laura; Cantero-Navarro, Elena; Lavoz, Carolina; Fierro-Fernández, Marta; Poveda, Jonay; Rayego-Mateos, Sandra; Rodrigues-Diez, Raúl R; Morgado-Pascual, José Luis; Orejudo, Macarena; Mezzano, Sergio; Ruiz-Ortega, Marta

    2018-02-10

    Notch pathway regulates key processes in the kidney, involved in embryonic development and tissue damage. In many human chronic renal diseases a local activation of Notch pathway has been described, suggesting that several components of Notch pathway could be considered as biomarkers of renal damage. Experimental studies by genetic modulation of Notch components or pharmacological approaches by γ-secretase inhibitors have demonstrated the role of this pathway in renal regeneration renal, podocyte apoptosis, proliferation and fibroblasts activation, and induction of epithelial to mesenchymal transition of tubular epithelial cells. Recent studies suggest an interaction between Notch and NF-κB pathway involved in the regulation of renal inflammatory process. On the other hand, there are some miRNAs that could regulate Notch components and down-stream responses. All these data suggest that Notch blockade could be a novel therapeutic option for renal diseases. Copyright © 2018 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  16. The clathrin-binding motif and the J-domain of Drosophila Auxilin are essential for facilitating Notch ligand endocytosis

    PubMed Central

    Kandachar, Vasundhara; Bai, Ting; Chang, Henry C

    2008-01-01

    Background Ligand endocytosis plays a critical role in regulating the activity of the Notch pathway. The Drosophila homolog of auxilin (dAux), a J-domain-containing protein best known for its role in the disassembly of clathrin coats from clathrin-coated vesicles, has recently been implicated in Notch signaling, although its exact mechanism remains poorly understood. Results To understand the role of auxilin in Notch ligand endocytosis, we have analyzed several point mutations affecting specific domains of dAux. In agreement with previous work, analysis using these stronger dAux alleles shows that dAux is required for several Notch-dependent processes, and its function during Notch signaling is required in the signaling cells. In support of the genetic evidences, the level of Delta appears elevated in dAux deficient cells, suggesting that the endocytosis of Notch ligand is disrupted. Deletion analysis shows that the clathrin-binding motif and the J-domain, when over-expressed, are sufficient for rescuing dAux phenotypes, implying that the recruitment of Hsc70 to clathrin is a critical role for dAux. However, surface labeling experiment shows that, in dAux mutant cells, Delta accumulates at the cell surface. In dAux mutant cells, clathrin appears to form large aggregates, although Delta is not enriched in these aberrant clathrin-positive structures. Conclusion Our data suggest that dAux mutations inhibit Notch ligand internalization at an early step during clathrin-mediated endocytosis, before the disassembly of clathrin-coated vesicles. Further, the inhibition of ligand endocytosis in dAux mutant cells possibly occurs due to depletion of cytosolic pools of clathrin via the formation of clathrin aggregates. Together, our observations argue that ligand endocytosis is critical for Notch signaling and auxilin participates in Notch signaling by facilitating ligand internalization. PMID:18466624

  17. Epigenetic regulation of NOTCH1 and NOTCH3 by KMT2A inhibits glioma proliferation.

    PubMed

    Huang, Yin-Cheng; Lin, Sheng-Jia; Shih, Hung-Yu; Chou, Chung-Han; Chu, Hsiao-Han; Chiu, Ching-Chi; Yuh, Chiou-Hwa; Yeh, Tu-Hsueh; Cheng, Yi-Chuan

    2017-09-08

    Glioblastomas are among the most fatal brain tumors; however, the molecular determinants of their tumorigenic behavior are not adequately defined. In this study, we analyzed the role of KMT2A in the glioblastoma cell line U-87 MG. KMT2A knockdown promoted cell proliferation. Moreover, it increased the DNA methylation of NOTCH1 and NOTCH3 and reduced the expression of NOTCH1 and NOTCH3 . NOTCH1 or NOTCH3 activation inhibited U-87 MG cell proliferation, whereas NOTCH1 and NOTCH3 inhibition by shRNAs induced cell proliferation, thus demonstrating the tumor-suppressive ability of NOTCH1 and NOTCH3 in U-87 MG cells. The induced cell proliferation caused by KMT2A knockdown could be nullified by using either constitutively active NOTCH1 or constitutively active NOTCH3. This result demonstrates that KMT2A positively regulates NOTCH1 and NOTCH3 and that this mechanism is essential for inhibiting the U-87 MG cell proliferation. The role of KMT2A knockdown in promoting tumor growth was further confirmed in vivo by transplanting U-87 MG cells into the brains of zebrafish larvae. In conclusion, we identified KMT2A-NOTCH as a negative regulatory cascade for glioblastoma cell proliferation, and this result provides important information for KMT2A- or NOTCH-targeted therapeutic strategies for brain tumors.

  18. The archetypal R90C CADASIL-NOTCH3 mutation retains NOTCH3 function in vivo.

    PubMed

    Monet, Marie; Domenga, Valérie; Lemaire, Barbara; Souilhol, Céline; Langa, Francina; Babinet, Charles; Gridley, Thomas; Tournier-Lasserve, Elisabeth; Cohen-Tannoudji, Michel; Joutel, Anne

    2007-04-15

    Cerebral Autosomal Dominant Arteriopathy with Subcortical infarcts and Leukoencephalopathy (CADASIL) is the most prominent known cause of inherited stroke and vascular dementia in human adult. The disease gene, NOTCH3, encodes a transmembrane receptor primarily expressed in arterial smooth muscle cells (SMC). Pathogenic mutations lead to an odd number of cysteine residues within the NOTCH3 extracellular domain (NOTCH3(ECD)), and are associated with progressive accumulation of NOTCH3(ECD) at the SMC plasma membrane. The murine homolog, Notch3, is dispensable for viability but required post-natally for the elaboration and maintenance of arteries. How CADASIL-associated mutations impact NOTCH3 function remains a fundamental, yet unresolved issue. Particularly, whether NOTCH3(ECD) accumulation may titrate the ligand and inhibit the normal pathway is unknown. Herein, using genetic analyses in the mouse, we assessed the functional significance of an archetypal CADASIL-associated mutation (R90C), in vivo, in brain arteries. We show that transgenic mouse lines expressing either the wild-type human NOTCH3 or the mutant R90C human NOTCH3, at comparable and physiological levels, can rescue the arterial defects of Notch3-/- mice to similar degrees. In vivo assessment of NOTCH3/RBP-Jk activity provides evidence that the mutant NOTCH3 protein exhibits normal level of activity in brain arteries. Remarkably, the mutant NOTCH3 protein remains functional and does not exhibit dominant negative interfering activity, even when NOTCH3(ECD) accumulates. Collectively, these data suggest a model that invokes novel pathogenic roles for the mutant NOTCH3 protein rather than compromised NOTCH3 function as the primary determinant of the CADASIL arteriopathy.

  19. Leptin-promoted human extravillous trophoblast invasion is MMP14 dependent and requires the cross talk between Notch1 and PI3K/Akt signaling.

    PubMed

    Wang, Huayang; Cheng, Huanhuan; Shao, Qianqian; Dong, Zhaogang; Xie, Qi; Zhao, Lei; Wang, Qingjie; Kong, Beihua; Qu, Xun

    2014-04-01

    The overexpression of leptin is a crucial feature for the maintenance of pregnancy. The effects of leptin on trophoblast invasion are important to its reproductive function, but the underlying mechanisms remain poorly understood. MMP14 is a member of matrix metalloproteinase (MMP) family that is closely involved in the invasion process. Here, we characterized the importance of MMP14 in the proinvasion effect of leptin on EVT cells and elucidated its molecular mechanisms. Transwell assay revealed that leptin promoted invasion of the immortalized EVT cell line HTR-8/SVneo in a dose- and time-related fashion. Further studies suggested that leptin enhanced HTR-8/SVneo cell invasion by up-regulating MMP14 expression and that knockdown of MMP14 by small interference RNA (siRNA) blocked the proinvasion effect of leptin. Notably, leptin promoted the expression of Notch1 receptor and activated its signaling in HTR-8/SVneo cells, and blocking this pathway by siRNA inhibited both leptin-enhanced MMP14 expression and invasiveness of HTR-8/SVneo cells. Such effects of Notch1 signaling were related with the activation of the PI3K/Akt pathway, which was significantly activated after leptin stimulation and was interfered by Notch1 signaling perturbation. Taken together, our observations suggest that leptin is an effective regulator of MMP14 expression, which consequently plays critical roles in invasion of EVT cells. The promoting effects of leptin on MMP14 require the cross talk between Notch1 and PI3K/Akt signaling pathways.

  20. Prolyl-isomerase Pin1 controls Notch3 protein expression and regulates T-ALL progression.

    PubMed

    Franciosa, G; Diluvio, G; Gaudio, F Del; Giuli, M V; Palermo, R; Grazioli, P; Campese, A F; Talora, C; Bellavia, D; D'Amati, G; Besharat, Z M; Nicoletti, C; Siebel, C W; Choy, L; Rustighi, A; Sal, G Del; Screpanti, I; Checquolo, S

    2016-09-08

    Deregulated Notch signaling is associated with T-cell Acute Lymphoblastic Leukemia (T-ALL) development and progression. Increasing evidence reveals that Notch pathway has an important role in the invasion ability of tumor cells, including leukemia, although the underlying molecular mechanisms remain mostly unclear. Here, we show that Notch3 is a novel target protein of the prolyl-isomerase Pin1, which is able to regulate Notch3 protein processing and to stabilize the cleaved product, leading to the increased expression of the intracellular domain (N3IC), finally enhancing Notch3-dependent invasiveness properties. We demonstrate that the combined inhibition of Notch3 and Pin1 in the Notch3-overexpressing human leukemic TALL-1 cells reduces their high invasive potential, by decreasing the expression of the matrix metalloprotease MMP9. Consistently, Pin1 depletion in a mouse model of Notch3-induced T-ALL, by reducing N3IC expression and signaling, impairs the expansion/invasiveness of CD4(+)CD8(+) DP cells in peripheral lymphoid and non-lymphoid organs. Notably, in in silico gene expression analysis of human T-ALL samples we observed a significant correlation between Pin1 and Notch3 expression levels, which may further suggest a key role of the newly identified Notch3-Pin1 axis in T-ALL aggressiveness and progression. Thus, combined suppression of Pin1 and Notch3 proteins may be exploited as an additional target therapy for T-ALL.

  1. Prolyl-isomerase Pin1 controls Notch3 protein expression and regulates T-ALL progression

    PubMed Central

    Franciosa, G; Diluvio, G; Gaudio, F Del; Giuli, M V; Palermo, R; Grazioli, P; Campese, A F; Talora, C; Bellavia, D; D'Amati, G; Besharat, Z M; Nicoletti, C; Siebel, C W; Choy, L; Rustighi, A; Sal, G Del; Screpanti, I; Checquolo, S

    2016-01-01

    Deregulated Notch signaling is associated with T-cell Acute Lymphoblastic Leukemia (T-ALL) development and progression. Increasing evidence reveals that Notch pathway has an important role in the invasion ability of tumor cells, including leukemia, although the underlying molecular mechanisms remain mostly unclear. Here, we show that Notch3 is a novel target protein of the prolyl-isomerase Pin1, which is able to regulate Notch3 protein processing and to stabilize the cleaved product, leading to the increased expression of the intracellular domain (N3IC), finally enhancing Notch3-dependent invasiveness properties. We demonstrate that the combined inhibition of Notch3 and Pin1 in the Notch3-overexpressing human leukemic TALL-1 cells reduces their high invasive potential, by decreasing the expression of the matrix metalloprotease MMP9. Consistently, Pin1 depletion in a mouse model of Notch3-induced T-ALL, by reducing N3IC expression and signaling, impairs the expansion/invasiveness of CD4+CD8+ DP cells in peripheral lymphoid and non-lymphoid organs. Notably, in in silico gene expression analysis of human T-ALL samples we observed a significant correlation between Pin1 and Notch3 expression levels, which may further suggest a key role of the newly identified Notch3-Pin1 axis in T-ALL aggressiveness and progression. Thus, combined suppression of Pin1 and Notch3 proteins may be exploited as an additional target therapy for T-ALL. PMID:26876201

  2. ADAM10 and γ-secretase regulate sensory regeneration in the avian vestibular organs.

    PubMed

    Warchol, Mark E; Stone, Jennifer; Barton, Matthew; Ku, Jeffrey; Veile, Rose; Daudet, Nicolas; Lovett, Michael

    2017-08-01

    The loss of sensory hair cells from the inner ear is a leading cause of hearing and balance disorders. The mammalian ear has a very limited ability to replace lost hair cells, but the inner ears of non-mammalian vertebrates can spontaneously regenerate hair cells after injury. Prior studies have shown that replacement hair cells are derived from epithelial supporting cells and that the differentiation of new hair cells is regulated by the Notch signaling pathway. The present study examined molecular influences on regeneration in the avian utricle, which has a particularly robust regenerative ability. Chicken utricles were placed in organotypic culture and hair cells were lesioned by application of the ototoxic antibiotic streptomycin. Cultures were then allowed to regenerate in vitro for seven days. Some specimens were treated with small molecule inhibitors of γ-secretase or ADAM10, proteases which are essential for transmission of Notch signaling. As expected, treatment with both inhibitors led to increased numbers of replacement hair cells. However, we also found that inhibition of both proteases resulted in increased regenerative proliferation. Subsequent experiments showed that inhibition of γ-secretase or ADAM10 could also trigger proliferation in undamaged utricles. To better understand these phenomena, we used RNA-Seq profiling to characterize changes in gene expression following γ-secretase inhibition. We observed expression patterns that were consistent with Notch pathway inhibition, but we also found that the utricular sensory epithelium contains numerous γ-secretase substrates that might regulate cell cycle entry and possibly supporting cell-to-hair cell conversion. Together, our data suggest multiple roles for γ-secretase and ADAM10 in vestibular hair cell regeneration. Copyright © 2017. Published by Elsevier Inc.

  3. Isolation and Characterization of Prostate Cancer Stem Cells

    DTIC Science & Technology

    2013-10-01

    et al. Targeting cancer stem cells by inhibiting Wnt, Notch, and Hedgehog pathways. Nat Rev Clin Oncol 2011;8:97–106. 26] Guise T. Examining the...Nitrogen or fixed in formalin and paraffin-embedded to evaluate anatomy and glandular architecture. The remainder of the tissue was mechan- ically and

  4. Notch-mediated lateral inhibition regulates proneural wave propagation when combined with EGF-mediated reaction diffusion

    PubMed Central

    Sato, Makoto; Yasugi, Tetsuo; Minami, Yoshiaki; Miura, Takashi; Nagayama, Masaharu

    2016-01-01

    Notch-mediated lateral inhibition regulates binary cell fate choice, resulting in salt and pepper patterns during various developmental processes. However, how Notch signaling behaves in combination with other signaling systems remains elusive. The wave of differentiation in the Drosophila visual center or “proneural wave” accompanies Notch activity that is propagated without the formation of a salt and pepper pattern, implying that Notch does not form a feedback loop of lateral inhibition during this process. However, mathematical modeling and genetic analysis clearly showed that Notch-mediated lateral inhibition is implemented within the proneural wave. Because partial reduction in EGF signaling causes the formation of the salt and pepper pattern, it is most likely that EGF diffusion cancels salt and pepper pattern formation in silico and in vivo. Moreover, the combination of Notch-mediated lateral inhibition and EGF-mediated reaction diffusion enables a function of Notch signaling that regulates propagation of the wave of differentiation. PMID:27535937

  5. NOTCH pathway inactivation promotes bladder cancer progression

    PubMed Central

    Maraver, Antonio; Fernandez-Marcos, Pablo J.; Cash, Timothy P.; Mendez-Pertuz, Marinela; Dueñas, Marta; Maietta, Paolo; Martinelli, Paola; Muñoz-Martin, Maribel; Martínez-Fernández, Mónica; Cañamero, Marta; Roncador, Giovanna; Martinez-Torrecuadrada, Jorge L.; Grivas, Dimitrios; de la Pompa, Jose Luis; Valencia, Alfonso; Paramio, Jesús M.; Real, Francisco X.; Serrano, Manuel

    2015-01-01

    NOTCH signaling suppresses tumor growth and proliferation in several types of stratified epithelia. Here, we show that missense mutations in NOTCH1 and NOTCH2 found in human bladder cancers result in loss of function. In murine models, genetic ablation of the NOTCH pathway accelerated bladder tumorigenesis and promoted the formation of squamous cell carcinomas, with areas of mesenchymal features. Using bladder cancer cells, we determined that the NOTCH pathway stabilizes the epithelial phenotype through its effector HES1 and, consequently, loss of NOTCH activity favors the process of epithelial-mesenchymal transition. Evaluation of human bladder cancer samples revealed that tumors with low levels of HES1 present mesenchymal features and are more aggressive. Together, our results indicate that NOTCH serves as a tumor suppressor in the bladder and that loss of this pathway promotes mesenchymal and invasive features. PMID:25574842

  6. Presenilin-Based Genetic Screens in Drosophila melanogaster Identify Novel Notch Pathway Modifiers

    PubMed Central

    Mahoney, Matt B.; Parks, Annette L.; Ruddy, David A.; Tiong, Stanley Y. K.; Esengil, Hanife; Phan, Alexander C.; Philandrinos, Panos; Winter, Christopher G.; Chatterjee, Runa; Huppert, Kari; Fisher, William W.; L'Archeveque, Lynn; Mapa, Felipa A.; Woo, Wendy; Ellis, Michael C.; Curtis, Daniel

    2006-01-01

    Presenilin is the enzymatic component of γ-secretase, a multisubunit intramembrane protease that processes several transmembrane receptors, such as the amyloid precursor protein (APP). Mutations in human Presenilins lead to altered APP cleavage and early-onset Alzheimer's disease. Presenilins also play an essential role in Notch receptor cleavage and signaling. The Notch pathway is a highly conserved signaling pathway that functions during the development of multicellular organisms, including vertebrates, Drosophila, and C. elegans. Recent studies have shown that Notch signaling is sensitive to perturbations in subcellular trafficking, although the specific mechanisms are largely unknown. To identify genes that regulate Notch pathway function, we have performed two genetic screens in Drosophila for modifiers of Presenilin-dependent Notch phenotypes. We describe here the cloning and identification of 19 modifiers, including nicastrin and several genes with previously undescribed involvement in Notch biology. The predicted functions of these newly identified genes are consistent with extracellular matrix and vesicular trafficking mechanisms in Presenilin and Notch pathway regulation and suggest a novel role for γ-tubulin in the pathway. PMID:16415372

  7. Presenilin-based genetic screens in Drosophila melanogaster identify novel notch pathway modifiers.

    PubMed

    Mahoney, Matt B; Parks, Annette L; Ruddy, David A; Tiong, Stanley Y K; Esengil, Hanife; Phan, Alexander C; Philandrinos, Panos; Winter, Christopher G; Chatterjee, Runa; Huppert, Kari; Fisher, William W; L'Archeveque, Lynn; Mapa, Felipa A; Woo, Wendy; Ellis, Michael C; Curtis, Daniel

    2006-04-01

    Presenilin is the enzymatic component of gamma-secretase, a multisubunit intramembrane protease that processes several transmembrane receptors, such as the amyloid precursor protein (APP). Mutations in human Presenilins lead to altered APP cleavage and early-onset Alzheimer's disease. Presenilins also play an essential role in Notch receptor cleavage and signaling. The Notch pathway is a highly conserved signaling pathway that functions during the development of multicellular organisms, including vertebrates, Drosophila, and C. elegans. Recent studies have shown that Notch signaling is sensitive to perturbations in subcellular trafficking, although the specific mechanisms are largely unknown. To identify genes that regulate Notch pathway function, we have performed two genetic screens in Drosophila for modifiers of Presenilin-dependent Notch phenotypes. We describe here the cloning and identification of 19 modifiers, including nicastrin and several genes with previously undescribed involvement in Notch biology. The predicted functions of these newly identified genes are consistent with extracellular matrix and vesicular trafficking mechanisms in Presenilin and Notch pathway regulation and suggest a novel role for gamma-tubulin in the pathway.

  8. The Human Papillomavirus Type 8 E6 Protein Interferes with NOTCH Activation during Keratinocyte Differentiation

    PubMed Central

    Meyers, Jordan M.; Spangle, Jennifer M.

    2013-01-01

    Cutaneous β-human papillomavirus (β-HPV) E6 proteins inhibit NOTCH signaling by associating with the transcriptional coactivator MAML1. NOTCH has tumor suppressor activities in epithelial cells and is activated during keratinocyte differentiation. Here we report that HPV type 8 (HPV8) E6 subverts NOTCH activation during keratinocyte differentiation by inhibiting RBPJ/MAML1 transcriptional activator complexes at NOTCH target DNA. NOTCH inhibition impairs epithelial differentiation and may thus contribute to β-HPV replication and viral oncogenesis. PMID:23365452

  9. Curcumin-mediated regulation of Notch1/hairy and enhancer of split-1/survivin: molecular targeting in cholangiocarcinoma.

    PubMed

    Koprowski, Steven; Sokolowski, Kevin; Kunnimalaiyaan, Selvi; Gamblin, T Clark; Kunnimalaiyaan, Muthusamy

    2015-10-01

    Cholangiocarcinoma (CCA) is highly malignant and characterized by poor prognosis with chemotherapeutic resistance. Therefore, continued development of novel, effective approaches are needed. Notch expression is markedly upregulated in CCA, but the utility of Notch1 inhibition is not defined. Based on recent findings, we hypothesized that curcumin, a polyphenolic phytochemical, suppresses CCA growth in vitro via inhibition of Notch1 signaling. Established CCA cell lines CCLP-1 and SG-231 were treated with varying concentrations of curcumin (0-20 μM). Viability was assessed through 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide and clonogenic assays. Evaluation of apoptosis was determined via Western analysis for apoptotic markers and Caspase-Glo 3/7 assay. Cell lysates were further analyzed via Western blotting for Notch1/HES-1/survivin pathway expression, cell cycle progression, and survival. Curcumin-treated CCA cells exhibited reduced viability compared with control treatment. Statistically significant reductions in cell viability were observed with curcumin treatment at concentrations of 7.5, 10, and 15 μM by approximately 10%, 48%, and 56% for CCLP-1 and 13%, 25%, and 50% for SG-231, respectively. On Western analysis, concentrations of ≥10 μM showed reductions in Notch1, HES-1, and survivin. Apoptosis was evidenced by an increase in expression of cleaved poly [ADP] ribose polymerase and an increase in caspase activity. Cyclin D1 (cell cycle progression) expression levels were also reduced with treatment. Curcumin effectively induces CCA (CCLP-1 and SG-231) growth suppression and apoptosis at relatively low treatment concentrations when compared with the previous research. A concomitant reduction of Notch1, HES-1, and survivin expression in CCA cell lines provides novel evidence for a potential antitumorigenic mechanism-of-action. To our knowledge, this is the first report showing reduction in HES-1 expression via protein analysis after treatment with curcumin. Such findings merit further investigation of curcumin-mediated inhibition of Notch signaling in CCA either alone or in combination with chemotherapeutic agents. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Notch signalling in cardiovasculogenesis: insight into their role in early cardiovascular development.

    PubMed

    Saravanakumar, Marimuthu; Devaraj, Halagowder

    2013-05-01

    The role of Notch signalling in congenital cardiovascular disease is evident by the identification of human mutations in several Notch signalling components, which also indicates the importance of activated Notch pathway in cardiovascular biology. Therefore, the aim of the present study is to investigate the expression pattern of the components of Notch signalling molecules and their role in mice embryonic heart and vascular development. Group A: normal control pregnant mice, group B: pregnant mice were injected with DMSO, group C: DAPT were subcutaneously injected to pregnant mice. The morphological and molecular changes of trabeculation-defective phenotype were analysed using histological, scanning electron microscope, immunoblot, immunolocalization and reverse transcriptase-PCR. E15.5 DAPT-treated mice revealed that there was a major reduction in the formation of septal walls between the ventricular chambers compared with normal control pregnant mice. VEGF expression was found in the DAPT treated and wild-type embryonic artery, whereas notch target genes GATA4, Hey1 expression were not found in the DAPT treated mice embryo. The role of Notch in ventricular development is supported by the trabeculation-defective phenotype seen in standard and endocardial-specific inhibition of Notch targets. The present study reveals the significant role of Notch signalling during the formation of ventricular septum and proper development of endothelial cell lineage and its precursor in mice cardiogenesis.

  11. c-Myc-Induced Survivin Is Essential for Promoting the Notch-Dependent T Cell Differentiation from Hematopoietic Stem Cells

    PubMed Central

    Haque, Rizwanul; Song, Jianyong; Haque, Mohammad; Lei, Fengyang; Sandhu, Praneet; Ni, Bing; Zheng, Songguo; Fang, Deyu; Yang, Jin-Ming; Song, Jianxun

    2017-01-01

    Notch is indispensable for T cell lineage commitment, and is needed for thymocyte differentiation at early phases. During early stages of T cell development, active Notch prevents other lineage potentials including B cell lineage and myeloid cell (e.g., dendritic cell) lineage. Nevertheless, the precise intracellular signaling pathways by which Notch promotes T cell differentiation remain unclear. Here we report that the transcription factor c-Myc is a key mediator of the Notch signaling–regulated T cell differentiation. In a well-established in vitro differentiation model of T lymphocytes from hematopoietic stem cells, we showed that Notch1 and 4 directly promoted c-Myc expression; dominant-negative (DN) c-Myc inhibited early T cell differentiation. Moreover, the c-Myc expression activated by Notch signaling increased the expression of survivin, an inhibitor of apoptosis (IAP) protein. We further demonstrated that over-expression of c-Myc increased the abundance of survivin and the T cell differentiation thereof, whereas dn c-Myc reduced survivin levels and concomitantly retarded the differentiation. The c-Myc–dependent survivin induction is functionally germane, because Notch-dependent T cell differentiation was canceled by the depletion of survivin. These results identify both c-Myc and survivin as important mediators of the Notch signaling–regulated differentiation of T lymphocytes from hematopoietic stem cells. PMID:28272325

  12. Epidermal Notch signalling: differentiation, cancer and adhesion.

    PubMed

    Watt, Fiona M; Estrach, Soline; Ambler, Carrie A

    2008-04-01

    The Notch pathway plays an important role in regulating epidermal differentiation. Notch ligands, receptors and effectors are expressed in a complex and dynamic pattern in embryonic and adult skin. Genetic ablation or activation of the pathway reveals that Notch signalling promotes differentiation of the hair follicle, sebaceous gland and interfollicular epidermal lineages and that Notch acts as an epidermal tumour suppressor. Notch signalling interacts with a range of other pathways to fulfil these functions and acts via RBP-Jkappa dependent and independent mechanisms. The effects on differentiation can be cell autonomous and non-autonomous, and Notch contributes to stem cell clustering via modulation of cell adhesion.

  13. Direct induction of T lymphocyte-specific gene expression by the mammalian Notch signaling pathway

    PubMed Central

    Reizis, Boris; Leder, Philip

    2002-01-01

    The Notch signaling pathway regulates the commitment and early development of T lymphocytes. We studied Notch-mediated induction of the pre-T cell receptor α (pTa) gene, a T-cell-specific transcriptional target of Notch. The pTa enhancer was activated by Notch signaling and contained binding sites for its nuclear effector, CSL. Mutation of the CSL-binding sites abolished enhancer induction by Notch and delayed the up-regulation of pTa transgene expression during T cell lineage commitment. These results show a direct mechanism of stage- and tissue-specific gene induction by the mammalian Notch/CSL signaling pathway. PMID:11825871

  14. Notch-signalling is required for head regeneration and tentacle patterning in Hydra.

    PubMed

    Münder, Sandra; Tischer, Susanne; Grundhuber, Maresa; Büchels, Nathalie; Bruckmeier, Nadine; Eckert, Stefanie; Seefeldt, Carolin A; Prexl, Andrea; Käsbauer, Tina; Böttger, Angelika

    2013-11-01

    Local self-activation and long ranging inhibition provide a mechanism for setting up organising regions as signalling centres for the development of structures in the surrounding tissue. The adult hydra hypostome functions as head organiser. After hydra head removal it is newly formed and complete heads can be regenerated. The molecular components of this organising region involve Wnt-signalling and β-catenin. However, it is not known how correct patterning of hypostome and tentacles are achieved in the hydra head and whether other signals in addition to HyWnt3 are needed for re-establishing the new organiser after head removal. Here we show that Notch-signalling is required for re-establishing the organiser during regeneration and that this is due to its role in restricting tentacle activation. Blocking Notch-signalling leads to the formation of irregular head structures characterised by excess tentacle tissue and aberrant expression of genes that mark the tentacle boundaries. This indicates a role for Notch-signalling in defining the tentacle pattern in the hydra head. Moreover, lateral inhibition by HvNotch and its target HyHes are required for head regeneration and without this the formation of the β-catenin/Wnt dependent head organiser is impaired. Work on prebilaterian model organisms has shown that the Wnt-pathway is important for setting up signalling centres for axial patterning in early multicellular animals. Our data suggest that the integration of Wnt-signalling with Notch-Delta activity was also involved in the evolution of defined body plans in animals. © 2013 Elsevier Inc. All rights reserved.

  15. Characteristics of Notch2(+) pancreatic cancer stem-like cells and the relationship with centroacinar cells.

    PubMed

    Zhou, Zhu-Chao; Dong, Qiang-Gang; Fu, De-Liang; Gong, Yi-Yi; Ni, Quan-Xing

    2013-08-01

    Notch2, a surface marker in cell lines, is used to isolate, identify and localise pancreatic cancer stem-like cells and is a target for therapy of these cells. Sphere formation was induced in Panc-1 and Bxpc-3 pancreatic cancer cell lines, and Notch2(+) cells were separated from Bxpc-3 and Panc-1 cell lines by magnetic activated cell sorting (MACS). Expression of stem cell-related markers, OCT4, Nanog and PDX1, were measured by immunofluorescent (IF) staining. Expression of Notch2 was also determined immunohistochemically in pancreatic tissues. Notch2(+) cells were transplanted in subcutaneous of mice. AQP1 and AQP5 were also measured by IF in Bxpc-3 cells. The Notch signal pathway inhibitor, Compound E (CE), was used to treat Notch2(+) Bxpc-3 cells, and their vitalities were subsequently measured by the CCK-8 method. Positive expression of OCT4, Nanog and PDX1 was observed in Notch2(+) cells. Notch2(+) cells at centroacinar cell (CAC) and terminal ductal locations expressed AQP1 and AQP5. They were strongly tumourigenic in mice, and CE inhibited proliferation of Notch2(+) Bxpc-3 cells to some degree. OCT4 and Nanog can be used as markers of self-renewal in pancreatic cancer stem cells. Notch2(+) cells in human pancreatic cancer Bxpc-3 and Panc-1 cell lines had the properties of cancer stem cells. The results suggest that Notch2(+) pancreatic cancer stem-like cells had a close relationship with CAC. © 2013 International Federation for Cell Biology.

  16. Activation of Notch3 in Glomeruli Promotes the Development of Rapidly Progressive Renal Disease

    PubMed Central

    El Machhour, Fala; Keuylian, Zela; Kavvadas, Panagiotis; Dussaule, Jean-Claude

    2015-01-01

    Notch3 expression is found in the glomerular podocytes of patients with lupus nephritis or focal segmental GN but not in normal kidneys. Here, we show that activation of the Notch3 receptor in the glomeruli is a turning point inducing phenotypic changes in podocytes promoting renal inflammation and fibrosis and leading to disease progression. In a model of rapidly progressive GN, Notch3 expression was induced by several-fold in podocytes concurrently with disease progression. By contrast, mice lacking Notch3 expression were protected because they exhibited less proteinuria, uremia, and inflammatory infiltration. Podocyte outgrowth from glomeruli isolated from wild-type mice during the early phase of the disease was higher than outgrowth from glomeruli of mice lacking Notch3. In vitro studies confirmed that podocytes expressing active Notch3 reorganize their cytoskeleton toward a proliferative/migratory and inflammatory phenotype. We then administered antisense oligodeoxynucleotides targeting Notch3 or scramble control oligodeoxynucleotides in wild-type mice concomitant to disease induction. Both groups developed chronic renal disease, but mice injected with Notch3 antisense had lower values of plasma urea and proteinuria and inflammatory infiltration. The improvement of renal function was accompanied by fewer deposits of fibrin within the glomeruli and by decreased peritubular inflammation. Finally, abnormal Notch3 staining was observed in biopsy samples of patients with crescentic GN. These results demonstrate that abnormal activation of Notch3 may be involved in the progression of renal disease by promoting migratory and proinflammatory pathways. Inhibiting Notch3 activation could be a novel, promising approach to treat GN. PMID:25421557

  17. Transient gamma-secretase inhibition accelerates and enhances fracture repair likely via Notch signaling modulation

    PubMed Central

    Wang, Cuicui; Shen, Jie; Yukata, Kiminori; Inzana, Jason A.; O'Keefe, Regis J.; Awad, Hani A.; Hilton, Matthew J.

    2014-01-01

    Approximately 10% of skeletal fractures result in healing complications and non-union, while most fractures repair with appropriate stabilization and without pharmacologic intervention. It is the latter injuries that cannot be underestimated as the expenses associated with their treatment and subsequent lost productivity are predicted to increase to over $74 billion by 2015. During fracture repair, local mesenchymal stem/progenitor cells (MSCs) differentiate to form new cartilage and bone, reminiscent of events during skeletal development. We previously demonstrated that permanent loss of gamma-secretase activity and Notch signaling accelerates bone and cartilage formation from MSC progenitors during skeletal development, leading to pathologic acquisition of bone and depletion of bone marrow derived MSCs. Here, we investigated whether transient and systemic gamma-secretase and Notch inhibition is capable of accelerating and enhancing fracture repair by promoting controlled MSC differentiation near the fracture site. Our radiographic, microCT, histological, cell and molecular analyses reveal that single and intermittent gamma-secretase inhibitor (GSI) treatments significantly enhance cartilage and bone callus formation via the promotion of MSC differentiation, resulting in only a moderate reduction of local MSCs. Biomechanical testing further demonstrates that GSI treated fractures exhibit superior strength earlier in the healing process, with single dose GSI treated fractures exhibiting bone strength approaching that of un-fractured tibiae. These data further establish that transient inhibition of gamma-secretase activity and Notch signaling temporarily increases osteoclastogenesis and accelerates bone remodeling, which coupled with the effects on MSCs likely explains the accelerated and enhanced fracture repair. Therefore, we propose that the Notch pathway serves as an important therapeutic target during skeletal fracture repair. PMID:25527421

  18. Notch Signaling Augments BMP9-Induced Bone Formation by Promoting the Osteogenesis-Angiogenesis Coupling Process in Mesenchymal Stem Cells (MSCs).

    PubMed

    Liao, Junyi; Wei, Qiang; Zou, Yulong; Fan, Jiaming; Song, Dongzhe; Cui, Jing; Zhang, Wenwen; Zhu, Yunxiao; Ma, Chao; Hu, Xue; Qu, Xiangyang; Chen, Liqun; Yu, Xinyi; Zhang, Zhicai; Wang, Claire; Zhao, Chen; Zeng, Zongyue; Zhang, Ruyi; Yan, Shujuan; Wu, Tingting; Wu, Xingye; Shu, Yi; Lei, Jiayan; Li, Yasha; Luu, Hue H; Lee, Michael J; Reid, Russell R; Ameer, Guillermo A; Wolf, Jennifer Moriatis; He, Tong-Chuan; Huang, Wei

    2017-01-01

    Mesenchymal stem cells (MSCs) are multipotent progenitors that can differentiate into several lineages including bone. Successful bone formation requires osteogenesis and angiogenesis coupling of MSCs. Here, we investigate if simultaneous activation of BMP9 and Notch signaling yields effective osteogenesis-angiogenesis coupling in MSCs. Recently-characterized immortalized mouse adipose-derived progenitors (iMADs) were used as MSC source. Transgenes BMP9, NICD and dnNotch1 were expressed by adenoviral vectors. Gene expression was determined by qPCR and immunohistochem¡stry. Osteogenic activity was assessed by in vitro assays and in vivo ectopic bone formation model. BMP9 upregulated expression of Notch receptors and ligands in iMADs. Constitutively-active form of Notch1 NICD1 enhanced BMP9-induced osteogenic differentiation both in vitro and in vivo, which was effectively inhibited by dominant-negative form of Notch1 dnNotch1. BMP9- and NICD1-transduced MSCs implanted with a biocompatible scaffold yielded highly mature bone with extensive vascularization. NICD1 enhanced BMP9-induced expression of key angiogenic regulators in iMADs and Vegfa in ectopic bone, which was blunted by dnNotch1. Notch signaling may play an important role in BMP9-induced osteogenesis and angiogenesis. It's conceivable that simultaneous activation of the BMP9 and Notch pathways should efficiently couple osteogenesis and angiogenesis of MSCs for successful bone tissue engineering. © 2017 The Author(s)Published by S. Karger AG, Basel.

  19. Modulation of notch signaling pathway to prevent H2O2/menadione-induced SK-N-MC cells death by EUK134.

    PubMed

    Kamarehei, Maryam; Yazdanparast, Razieh

    2014-10-01

    The brain in Alzheimer's disease is under increased oxidative stress, and this may have a role in the pathogenesis and neural death in this disorder. It has been verified that numerous signaling pathways involved in neurodegenerative disorders are activated in response to reactive oxygen species (ROS). EUK134, a synthetic salen-manganese antioxidant complex, has been found to possess many interesting pharmacological activities awaiting exploration. The present study is to characterize the role of Notch signaling in apoptotic cell death of SK-N-MC cells. The cells were treated with hydrogen peroxide (H2O2) or menadione to induce oxidative stress. The free-radical scavenging capabilities of EUK134 were studied through the MTT assay, glutathione peroxidase (GPx) enzyme activity assay, and glutathione (GSH) Levels. The extents of lipid peroxidation, protein carbonyl formation, and intracellular ROS levels, as markers of oxidative stress, were also studied. Our results showed that H2O2/menadione reduced GSH levels and GPx activity. However, EUK134 protected cells against ROS-induced cell death by down-regulation of lipid peroxidation and protein carbonyl formation as well as restoration of antioxidant enzymes activity. ROS induced apoptosis and increased NICD and HES1 expression. Inhibition of NICD production proved that Notch signaling is involved in apoptosis through p53 activation. Moreover, H2O2/menadione led to Numb protein down-regulation which upon EUK134 pretreatment, its level increased and subsequently prevented Notch pathway activation. We indicated that EUK134 can be a promising candidate in designing natural-based drugs for ROS-induced neurodegenerative diseases. Collectively, ROS activated Notch signaling in SK-N-MC cells leading to cell apoptosis.

  20. An activated form of ADAM10 is tumor selective and regulates cancer stem-like cells and tumor growth

    PubMed Central

    Saha, Nayanendu; Eissman, Moritz F.; Xu, Kai; Llerena, Carmen; Kusebauch, Ulrike; Ding, Bi-Sen; Cao, Zhongwei; Rafii, Shahin; Ernst, Matthias; Scott, Andrew M.; Nikolov, Dimitar B.; Lackmann, Martin

    2016-01-01

    The transmembrane metalloprotease ADAM10 sheds a range of cell surface proteins, including ligands and receptors of the Notch, Eph, and erbB families, thereby activating signaling pathways critical for tumor initiation and maintenance. ADAM10 is thus a promising therapeutic target. Although widely expressed, its activity is normally tightly regulated. We now report prevalence of an active form of ADAM10 in tumors compared with normal tissues, in mouse models and humans, identified by our conformation-specific antibody mAb 8C7. Structure/function experiments indicate mAb 8C7 binds an active conformation dependent on disulfide isomerization and oxidative conditions, common in tumors. Moreover, this active ADAM10 form marks cancer stem-like cells with active Notch signaling, known to mediate chemoresistance. Importantly, specific targeting of active ADAM10 with 8C7 inhibits Notch activity and tumor growth in mouse models, particularly regrowth after chemotherapy. Our results indicate targeted inhibition of active ADAM10 as a potential therapy for ADAM10-dependent tumor development and drug resistance. PMID:27503072

  1. An activated form of ADAM10 is tumor selective and regulates cancer stem-like cells and tumor growth.

    PubMed

    Atapattu, Lakmali; Saha, Nayanendu; Chheang, Chanly; Eissman, Moritz F; Xu, Kai; Vail, Mary E; Hii, Linda; Llerena, Carmen; Liu, Zhanqi; Horvay, Katja; Abud, Helen E; Kusebauch, Ulrike; Moritz, Robert L; Ding, Bi-Sen; Cao, Zhongwei; Rafii, Shahin; Ernst, Matthias; Scott, Andrew M; Nikolov, Dimitar B; Lackmann, Martin; Janes, Peter W

    2016-08-22

    The transmembrane metalloprotease ADAM10 sheds a range of cell surface proteins, including ligands and receptors of the Notch, Eph, and erbB families, thereby activating signaling pathways critical for tumor initiation and maintenance. ADAM10 is thus a promising therapeutic target. Although widely expressed, its activity is normally tightly regulated. We now report prevalence of an active form of ADAM10 in tumors compared with normal tissues, in mouse models and humans, identified by our conformation-specific antibody mAb 8C7. Structure/function experiments indicate mAb 8C7 binds an active conformation dependent on disulfide isomerization and oxidative conditions, common in tumors. Moreover, this active ADAM10 form marks cancer stem-like cells with active Notch signaling, known to mediate chemoresistance. Importantly, specific targeting of active ADAM10 with 8C7 inhibits Notch activity and tumor growth in mouse models, particularly regrowth after chemotherapy. Our results indicate targeted inhibition of active ADAM10 as a potential therapy for ADAM10-dependent tumor development and drug resistance. © 2016 Atapattu et al.

  2. Disruption of Cell-Cell Contact-mediated Notch Signaling via Hydrogel Encapsulation Reduces Mesenchymal Stem Cell Chondrogenic Potential

    PubMed Central

    Chen, Amanda X.; Hoffman, Michael D.; Chen, Caressa S.; Shubin, Andrew D.; Reynolds, Daniel S.; Benoit, Danielle S. W.

    2015-01-01

    Cell-cell contact-mediated Notch signaling is essential for mesenchymal stem cell (MSC) chondrogenesis during development. However, subsequent deactivation of Notch signaling is also required to allow for stem cell chondrogenic progression. Recent literature has shown that Notch signaling can also influence Wnt/β-catenin signaling, critical for MSC differentiation, through perturbations in cell-cell contacts. Traditionally, abundant cell-cell contacts, consistent with development, are emulated in vitro using pellet cultures for chondrogenesis. However, cells are often encapsulated within biomaterials-based scaffolds, such as hydrogels, to improve therapeutic cell localization in vivo. To explore the role of Notch and Wnt/β-catenin signaling in the context of hydrogel-encapsulated MSC chondrogenesis, we compared signaling and differentiation capacity of MSCs in both hydrogels and traditional pellet cultures. We demonstrate that encapsulation within poly(ethylene glycol) (PEG) hydrogels reduces cell-cell contacts, and both Notch (7.5-fold) and Wnt/β-catenin (84.7-fold) pathway activation. Finally, we demonstrate that following establishment of cell-cell contacts and transient Notch signaling in pellet cultures, followed by Notch signaling deactivation, resulted in a 1.5-fold increase in MSC chondrogenesis. Taken together, these findings support that cellular condensation, and the establishment of initial cell-cell contacts is critical for MSC chondrogenesis, and this process is inhibited by hydrogel encapsulation. PMID:25504509

  3. PEST domain mutations in Notch receptors comprise an oncogenic driver segment in triple-negative breast cancer sensitive to a γ-secretase inhibitor.

    PubMed

    Wang, Kai; Zhang, Qin; Li, Danan; Ching, Keith; Zhang, Cathy; Zheng, Xianxian; Ozeck, Mark; Shi, Stephanie; Li, Xiaorong; Wang, Hui; Rejto, Paul; Christensen, James; Olson, Peter

    2015-03-15

    To identify and characterize novel, activating mutations in Notch receptors in breast cancer and to determine response to the gamma secretase inhibitor (GSI) PF-03084014. We used several computational approaches, including novel algorithms, to analyze next-generation sequencing data and related omic datasets from The Cancer Genome Atlas (TCGA) breast cancer cohort. Patient-derived xenograft (PDX) models were sequenced, and Notch-mutant models were treated with PF-03084014. Gene-expression and functional analyses were performed to study the mechanism of activation through mutation and inhibition by PF-03084014. We identified mutations within and upstream of the PEST domains of NOTCH1, NOTCH2, and NOTCH3 in the TCGA dataset. Mutations occurred via several genetic mechanisms and compromised the function of the PEST domain, a negative regulatory domain commonly mutated in other cancers. Focal amplifications of NOTCH2 and NOTCH3 were also observed, as were heterodimerization or extracellular domain mutations at lower incidence. Mutations and amplifications often activated the Notch pathway as evidenced by increased expression of canonical Notch target genes, and functional mutations were significantly enriched in the triple-negative breast cancer subtype (TNBC). PDX models were also identified that harbored PEST domain mutations, and these models were highly sensitive to PF-03084014. This work suggests that Notch-altered breast cancer constitutes a bona fide oncogenic driver segment with the most common alteration being PEST domain mutations present in multiple Notch receptors. Importantly, functional studies suggest that this newly identified class can be targeted with Notch inhibitors, including GSIs. ©2015 American Association for Cancer Research.

  4. Development of the Drosophila entero-endocrine lineage and its specification by the Notch signaling pathway

    PubMed Central

    Takashima, Shigeo; Adams, Katrina L.; Ortiz, Paola A.; Ying, Chong T.; Moridzadeh, Rameen; Younossi-Hartenstein, Amelia; Hartenstein, Volker

    2013-01-01

    In this paper we have investigated the developmental-genetic steps that shape the entero-endocrine system of Drosophila melanogaster from the embryo to the adult. The process starts in the endoderm of the early embryo where precursors of endocrine cells and enterocytes of the larval midgut, as well as progenitors of the adult midgut, are specified by a Notch signaling-dependent mechanism. In a second step that occurs during the late larval period, enterocytes and endocrine cells of a transient pupal midgut are selected from within the clusters of adult midgut progenitors. As in the embryo, activation of the Notch pathway triggers enterocyte differentiation, and inhibits cells from further proliferation or choosing the endocrine fate. The third step of entero-endocrine cell development takes place at a mid-pupal stage. Before this time point, the epithelial layer destined to become the adult midgut is devoid of endocrine cells. However, precursors of the intestinal midgut stem cells (pISCs) are already present. After an initial phase of symmetric divisions which causes an increase in their own population size, pISCs start to spin off cells that become postmitotic and express the endocrine fate marker, Prospero. Activation of Notch in pISCs forces these cells into an enterocyte fate. Loss of Notch function causes an increase in the proliferatory activity of pISCs, as well as a higher ratio of Prospero-positive cells. PMID:21382366

  5. Notch Decoys that Selectively Block Dll/Notch or Jagged/Notch Disrupt Angiogenesis by Unique Mechanisms to Inhibit Tumor Growth

    PubMed Central

    Kangsamaksin, Thaned; Murtomaki, Aino; Kofler, Natalie M.; Cuervo, Henar; Chaudhri, Reyhaan A.; Tattersall, Ian W.; Rosenstiel, Paul E.; Shawber, Carrie J.; Kitajewski, Jan

    2015-01-01

    A pro-angiogenic role for Jagged-dependent activation of Notch signaling in the endothelium has yet to be described. Using proteins that encoded different NOTCH1 EGF-like repeats, we identified unique regions of DLL-class and JAG-class ligand/receptor interactions, and developed Notch decoys that function as ligand-specific Notch inhibitors. N110-24 decoy blocked JAG1/JAG2-mediated NOTCH1 signaling, angiogenic sprouting in vitro and retinal angiogenesis, demonstrating JAG-dependent Notch signal activation promotes angiogenesis. In tumors, N110-24 decoy reduced angiogenic sprouting, vessel perfusion, pericyte coverage, and tumor growth. JAG/NOTCH signaling uniquely inhibited expression of anti-angiogenic sVEFGFR-1/sFlt-1. N11-13 decoy interfered with DLL1/DLL4-mediated NOTCH1 signaling and caused endothelial hypersprouting in vitro, in retinal angiogenesis and in tumors. Thus, blockade of JAG- or DLL-mediated Notch signaling inhibits angiogenesis by distinct mechanisms. JAG/Notch signaling positively regulates angiogenesis by suppressing sVEGFR-1/sFlt-1 and promoting mural/endothelial cell interactions. Blockade of JAG-class ligands represents a novel, viable therapeutic approach to block tumor angiogenesis and growth. PMID:25387766

  6. Jagged1 is the pathological link between Wnt and Notch pathways in colorectal cancer

    PubMed Central

    Rodilla, Verónica; Villanueva, Alberto; Obrador-Hevia, Antonia; Robert-Moreno, Àlex; Fernández-Majada, Vanessa; Grilli, Andrea; López-Bigas, Nuria; Bellora, Nicolás; Albà, M. Mar; Torres, Ferran; Duñach, Mireia; Sanjuan, Xavier; Gonzalez, Sara; Gridley, Thomas; Capella, Gabriel; Bigas, Anna; Espinosa, Lluís

    2009-01-01

    Notch has been linked to β-catenin-dependent tumorigenesis; however, the mechanisms leading to Notch activation and the contribution of the Notch pathway to colorectal cancer is not yet understood. By microarray analysis, we have identified a group of genes downstream of Wnt/β-catenin (down-regulated when blocking Wnt/β-catenin) that are directly regulated by Notch (repressed by γ-secretase inhibitors and up-regulated by active Notch1 in the absence of β-catenin signaling). We demonstrate that Notch is downstream of Wnt in colorectal cancer cells through β-catenin-mediated transcriptional activation of the Notch-ligand Jagged1. Consistently, expression of activated Notch1 partially reverts the effects of blocking Wnt/β-catenin pathway in tumors implanted s.c. in nude mice. Crossing APCMin/+ with Jagged1+/Δ mice is sufficient to significantly reduce the size of the polyps arising in the APC mutant background indicating that Notch is an essential modulator of tumorigenesis induced by nuclear β-catenin. We show that this mechanism is operating in human tumors from Familial Adenomatous Polyposis patients. We conclude that Notch activation, accomplished by β-catenin-mediated up-regulation of Jagged1, is required for tumorigenesis in the intestine. The Notch-specific genetic signature is sufficient to block differentiation and promote vasculogenesis in tumors whereas proliferation depends on both pathways. PMID:19325125

  7. Jagged1 is the pathological link between Wnt and Notch pathways in colorectal cancer.

    PubMed

    Rodilla, Verónica; Villanueva, Alberto; Obrador-Hevia, Antonia; Robert-Moreno, Alex; Fernández-Majada, Vanessa; Grilli, Andrea; López-Bigas, Nuria; Bellora, Nicolás; Albà, M Mar; Torres, Ferran; Duñach, Mireia; Sanjuan, Xavier; Gonzalez, Sara; Gridley, Thomas; Capella, Gabriel; Bigas, Anna; Espinosa, Lluís

    2009-04-14

    Notch has been linked to beta-catenin-dependent tumorigenesis; however, the mechanisms leading to Notch activation and the contribution of the Notch pathway to colorectal cancer is not yet understood. By microarray analysis, we have identified a group of genes downstream of Wnt/beta-catenin (down-regulated when blocking Wnt/beta-catenin) that are directly regulated by Notch (repressed by gamma-secretase inhibitors and up-regulated by active Notch1 in the absence of beta-catenin signaling). We demonstrate that Notch is downstream of Wnt in colorectal cancer cells through beta-catenin-mediated transcriptional activation of the Notch-ligand Jagged1. Consistently, expression of activated Notch1 partially reverts the effects of blocking Wnt/beta-catenin pathway in tumors implanted s.c. in nude mice. Crossing APC(Min/+) with Jagged1(+/Delta) mice is sufficient to significantly reduce the size of the polyps arising in the APC mutant background indicating that Notch is an essential modulator of tumorigenesis induced by nuclear beta-catenin. We show that this mechanism is operating in human tumors from Familial Adenomatous Polyposis patients. We conclude that Notch activation, accomplished by beta-catenin-mediated up-regulation of Jagged1, is required for tumorigenesis in the intestine. The Notch-specific genetic signature is sufficient to block differentiation and promote vasculogenesis in tumors whereas proliferation depends on both pathways.

  8. Synergistic antileukemic therapies in NOTCH1-induced T-ALL

    PubMed Central

    Sanchez-Martin, Marta; Ambesi-Impiombato, Alberto; Qin, Yue; Herranz, Daniel; Bansal, Mukesh; Girardi, Tiziana; Paietta, Elisabeth; Tallman, Martin S.; Rowe, Jacob M.; Califano, Andrea; Ferrando, Adolfo A.

    2017-01-01

    The Notch1 gene is a major oncogenic driver and therapeutic target in T-cell acute lymphoblastic leukemia (T-ALL). However, inhibition of NOTCH signaling with γ-secretase inhibitors (GSIs) has shown limited antileukemic activity in clinical trials. Here we performed an expression-based virtual screening to identify highly active antileukemic drugs that synergize with NOTCH1 inhibition in T-ALL. Among these, withaferin A demonstrated the strongest cytotoxic and GSI-synergistic antileukemic effects in vitro and in vivo. Mechanistically, network perturbation analyses showed eIF2A-phosphorylation–mediated inhibition of protein translation as a critical mediator of the antileukemic effects of withaferin A and its interaction with NOTCH1 inhibition. Overall, these results support a role for anti-NOTCH1 therapies and protein translation inhibitor combinations in the treatment of T-ALL. PMID:28174276

  9. RBP-Jκ-Dependent Notch Signaling Is Dispensable for Mouse Early Embryonic Development

    PubMed Central

    Souilhol, Céline; Cormier, Sarah; Tanigaki, Kenji; Babinet, Charles; Cohen-Tannoudji, Michel

    2006-01-01

    The Notch signaling pathway is an evolutionarily conserved signaling system which has been shown to be essential in cell fate specification and in numerous aspects of embryonic development in all metazoans thus far studied. We recently demonstrated that several components of the Notch signaling pathway, including the four Notch receptors and their five ligands known in mammals, are expressed in mouse oocytes, in mouse preimplantation embryos, or both. This suggested a possible implication of the Notch pathway in the first cell fate specification of the dividing mouse embryo, which results in the formation of the blastocyst. To address this issue directly, we generated zygotes in which both the maternal and the zygotic expression of Rbpsuh, a key element of the core Notch signaling pathway, were abrogated. We find that such zygotes give rise to blastocysts which implant and develop normally. Nevertheless, after gastrulation, these embryos die around midgestation, similarly to Rbpsuh-null mutants. This demonstrates that the RBP-Jκ-dependent pathway, otherwise called the canonical Notch pathway, is dispensable for blastocyst morphogenesis and the establishment of the three germ layers, ectoderm, endoderm, and mesoderm. These results are discussed in the light of recent observations which have challenged this conclusion. PMID:16782866

  10. RBP-Jkappa-dependent notch signaling is dispensable for mouse early embryonic development.

    PubMed

    Souilhol, Céline; Cormier, Sarah; Tanigaki, Kenji; Babinet, Charles; Cohen-Tannoudji, Michel

    2006-07-01

    The Notch signaling pathway is an evolutionarily conserved signaling system which has been shown to be essential in cell fate specification and in numerous aspects of embryonic development in all metazoans thus far studied. We recently demonstrated that several components of the Notch signaling pathway, including the four Notch receptors and their five ligands known in mammals, are expressed in mouse oocytes, in mouse preimplantation embryos, or both. This suggested a possible implication of the Notch pathway in the first cell fate specification of the dividing mouse embryo, which results in the formation of the blastocyst. To address this issue directly, we generated zygotes in which both the maternal and the zygotic expression of Rbpsuh, a key element of the core Notch signaling pathway, were abrogated. We find that such zygotes give rise to blastocysts which implant and develop normally. Nevertheless, after gastrulation, these embryos die around midgestation, similarly to Rbpsuh-null mutants. This demonstrates that the RBP-Jkappa-dependent pathway, otherwise called the canonical Notch pathway, is dispensable for blastocyst morphogenesis and the establishment of the three germ layers, ectoderm, endoderm, and mesoderm. These results are discussed in the light of recent observations which have challenged this conclusion.

  11. Activation of Notch3 in Glomeruli Promotes the Development of Rapidly Progressive Renal Disease.

    PubMed

    El Machhour, Fala; Keuylian, Zela; Kavvadas, Panagiotis; Dussaule, Jean-Claude; Chatziantoniou, Christos

    2015-07-01

    Notch3 expression is found in the glomerular podocytes of patients with lupus nephritis or focal segmental GN but not in normal kidneys. Here, we show that activation of the Notch3 receptor in the glomeruli is a turning point inducing phenotypic changes in podocytes promoting renal inflammation and fibrosis and leading to disease progression. In a model of rapidly progressive GN, Notch3 expression was induced by several-fold in podocytes concurrently with disease progression. By contrast, mice lacking Notch3 expression were protected because they exhibited less proteinuria, uremia, and inflammatory infiltration. Podocyte outgrowth from glomeruli isolated from wild-type mice during the early phase of the disease was higher than outgrowth from glomeruli of mice lacking Notch3. In vitro studies confirmed that podocytes expressing active Notch3 reorganize their cytoskeleton toward a proliferative/migratory and inflammatory phenotype. We then administered antisense oligodeoxynucleotides targeting Notch3 or scramble control oligodeoxynucleotides in wild-type mice concomitant to disease induction. Both groups developed chronic renal disease, but mice injected with Notch3 antisense had lower values of plasma urea and proteinuria and inflammatory infiltration. The improvement of renal function was accompanied by fewer deposits of fibrin within the glomeruli and by decreased peritubular inflammation. Finally, abnormal Notch3 staining was observed in biopsy samples of patients with crescentic GN. These results demonstrate that abnormal activation of Notch3 may be involved in the progression of renal disease by promoting migratory and proinflammatory pathways. Inhibiting Notch3 activation could be a novel, promising approach to treat GN. Copyright © 2015 by the American Society of Nephrology.

  12. Notch Signaling in Vascular Smooth Muscle Cells

    PubMed Central

    Baeten, J.T.; Lilly, B.

    2018-01-01

    The Notch signaling pathway is a highly conserved pathway involved in cell fate determination in embryonic development and also functions in the regulation of physiological processes in several systems. It plays an especially important role in vascular development and physiology by influencing angiogenesis, vessel patterning, arterial/venous specification, and vascular smooth muscle biology. Aberrant or dysregulated Notch signaling is the cause of or a contributing factor to many vascular disorders, including inherited vascular diseases, such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, associated with degeneration of the smooth muscle layer in cerebral arteries. Like most signaling pathways, the Notch signaling axis is influenced by complex interactions with mediators of other signaling pathways. This complexity is also compounded by different members of the Notch family having both overlapping and unique functions. Thus, it is vital to fully understand the roles and interactions of each Notch family member in order to effectively and specifically target their exact contributions to vascular disease. In this chapter, we will review the Notch signaling pathway in vascular smooth muscle cells as it relates to vascular development and human disease. PMID:28212801

  13. Perivascular Delivery of Notch 1 siRNA Inhibits Injury-Induced Arterial Remodeling

    PubMed Central

    Redmond, Eileen M.; Liu, Weimin; Hamm, Katie; Hatch, Ekaterina; Cahill, Paul A.; Morrow, David

    2014-01-01

    Objectives To determine the efficacy of perivascular delivery of Notch 1 siRNA in preventing injury-induced arterial remodeling. Methods and Results Carotid artery ligation was performed to induce arterial remodeling. After 14 days, morphometric analysis confirmed increased vSMC growth and subsequent media thickening and neointimal formation. Laser capture microdissection, quantitative qRT-PCR and immunoblot analysis of medial tissue revealed a significant increase in Notch1 receptor and notch target gene, Hrt 1 and 2 expression in the injured vessels. Perivascular delivery of Notch 1 siRNA by pluronic gel inhibited the injury-induced increase in Notch 1 receptor and target gene expression when compared to scrambled siRNA controls while concomitantly reducing media thickening and neointimal formation to pre-injury, sham-operated levels. Selective Notch 1 knockdown also reversed the injury-induced inhibition of pro-apoptotic Bax expression while decreasing injury-induced anti-apoptotic Bcl-XL expression to sham-operated control levels. In parallel experiments, proliferative cyclin levels, as measured by PCNA expression, were reversed to sham-operated control levels following selective Notch 1 knockdown. Conclusion These results suggest that injury-induced arterial remodeling can be successfully inhibited by localized perivascular delivery of Notch 1 siRNA. PMID:24416200

  14. Notch1 inhibition alters the CD44hi/CD24lo population and reduces the formation of brain metastases from breast cancer.

    PubMed

    McGowan, Patricia M; Simedrea, Carmen; Ribot, Emeline J; Foster, Paula J; Palmieri, Diane; Steeg, Patricia S; Allan, Alison L; Chambers, Ann F

    2011-07-01

    Brain metastasis from breast cancer is an increasingly important clinical problem. Here we assessed the role of CD44(hi)/CD24(lo) cells and pathways that regulate them, in an experimental model of brain metastasis. Notch signaling (mediated by γ-secretase) has been shown to contribute to maintenance of the cancer stem cell (CSC) phenotype. Cells sorted for a reduced stem-like phenotype had a reduced ability to form brain metastases compared with unsorted or CD44(hi)/CD24(lo) cells (P < 0.05; Kruskal-Wallis). To assess the effect of γ-secretase inhibition, cells were cultured with DAPT and the CD44/CD24 phenotypes quantified. 231-BR cells with a CD44(hi)/CD24(lo) phenotype was reduced by about 15% in cells treated with DAPT compared with DMSO-treated or untreated cells (P = 0.001, ANOVA). In vivo, mice treated with DAPT developed significantly fewer micro- and macrometastases compared with vehicle treated or untreated mice (P = 0.011, Kruskal-Wallis). Notch1 knockdown reduced the expression of CD44(hi)/CD24(lo) phenotype by about 20%. In vitro, Notch1 shRNA resulted in a reduction in cellular growth at 24, 48, and 72 hours time points (P = 0.033, P = 0.002, and P = 0.009, ANOVA) and about 60% reduction in Matrigel invasion was observed (P < 0.001, ANOVA). Cells transfected with shNotch1 formed significantly fewer macrometastases and micrometastases compared with scrambled shRNA or untransfected cells (P < 0.001; Kruskal-Wallis). These data suggest that the CSC phenotype contributes to the development of brain metastases from breast cancer, and this may arise in part from increased Notch activity. ©2011 AACR.

  15. The role of uric acid in the pathogenesis of diabetic retinopathy based on notch pathway.

    PubMed

    Zhu, Dan-Dan; Wang, Yun-Zhi; Zou, Chen; She, Xin-Ping; Zheng, Zhi

    2018-06-19

    Uric acid has been proposed as an independent risk factor of diabetic retinopathy. Although Notch signaling was reported to be affected in the presence of high concentrations of uric acid or glucose, the underlying mechanisms of hyperuricemia through the Notch signaling pathway to promote the development of diabetic retinopathy remain unknown. We incubated human retinal endothelial cells (HRECs) with high glucose, high uric acid and high glucose plus high glucose respectively and evaluated the apoptosis rate in different treated cells by Tunel staining. We induced diabetic model by intraperitoneally streptozotocin. Then healthy rats and diabetic rats were given with adenine and oteracil potassium by gavage. Using automatic biochemical analyzer to detect blood glucose, uric acid, urea nitrogen, creatinine levels, to verify the success of modeling. The expression and mRNA levels of ICAM-1, IL-6, MCP-1, TNF-a, receptors Notch 1, ligands Dll 1, Dll 4, Jagged 1, Jagged 2 were detected by RT-PCR and Western-Blot. Notch1 siRNA was used to interfere Notch signaling pathway, the expression and mRNA levels of ICAM-1, IL-6, MCP-1 and TNF-α was detected by RT-PCR and Western blot respectively. In vitro models, the apoptosis of HRECs cells in high uric acid plus high glucose group was the most significant. In vitro and vivo models, detection of inflammatory cytokines revealed that the expression of inflammatory cytokines increased most significantly in high uric acid plus high glucose group. Notch signaling pathway activity was also increased most significantly in high uric acid plus high glucose group. After Notch 1 siRNA transfection in high glucose and high glucose plus uric acid group, the activity of Notch signaling pathway was successfully down-regulated. We found that the apoptosis of HRECs was significantly decreased in cells transfected with Notch 1 siRNA compared to the blank vector group, and the expression of inflammatory cytokines in cells was also significantly decreased. Our study reported that high uric acid can promote the inflammation of the retina and increase the activity of Notch signaling pathway on the basis of high glucose. Hyperuricemia promotes the development of diabetic retinopathy by increasing the activity of Notch signaling pathway. Notch signaling pathway is a potential therapeutic target for diabetic retinopathy. Copyright © 2018. Published by Elsevier Inc.

  16. IMPACT (Imaging and Molecular Markers for Patients with Lung Cancer: Approaches with Molecular Targets and Complementary, Innovative and Therapeutic Modalities)

    DTIC Science & Technology

    2008-03-01

    preparation by Ximing Tang et al. b.3. NOTCH3 /JAGGED1 pathway. Notch3 (N3) is a member of the family of Notch transmembrane receptors, which are...Prudkin L, Liu D, Tchinda J, Woods D, Behrens C, Bekele BN, Moran C, Lee C, Aster JC, Zhou B-B, Wistuba II. NOTCH3 /JAGGED1 pathway is involved in non...Behrens C, Bekele BN, Moran C, Lee C, Aster JC, Zhou B-B, Wistuba II. NOTCH3 /JAGGED1 pathway is involved in non-small cell lung cancer pathogenesis

  17. Overexpression of protein O-fucosyltransferase 1 accelerates hepatocellular carcinoma progression via the Notch signaling pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ma, Lijie; Dong, Pingping; Liu, Longzi

    Aberrant activation of Notch signaling frequently occurs in liver cancer, and is associated with liver malignancies. However, the mechanisms regulating pathologic Notch activation in hepatocellular carcinoma (HCC) remain unclear. Protein O-fucosyltransferase 1 (Pofut1) catalyzes the addition of O-linked fucose to the epidermal growth factor-like repeats of Notch. In the present study, we detected the expression of Pofut1 in 8 HCC cell lines and 253 human HCC tissues. We reported that Pofut1 was overexpressed in HCC cell lines and clinical HCC tissues, and Pofut1 overexpression clinically correlated with the unfavorable survival and high disease recurrence in HCC. The in vitro assay demonstratedmore » that Pofut1 overexpression accelerated the cell proliferation and migration in HCC cells. Furthermore, Pofut1 overexpression promoted the binding of Notch ligand Dll1 to Notch receptor, and hence activated Notch signaling pathway in HCC cells, indicating that Pofut1 overexpression could be a reason for the aberrant activation of Notch signaling in HCC. Taken together, our findings indicated that an aberrant activated Pofut1-Notch pathway was involved in HCC progression, and blockage of this pathway could be a promising strategy for the therapy of HCC. - Highlights: • Pofut1 overexpression in HCC was correlated with aggressive tumor behaviors. • Pofut1 overexpression in HCC was associated with poor prognosis. • Pofut1 promoted cell proliferation, migration and invasion in hepatoma cells. • Pofut1 activated Notch signaling pathway in hepatoma cells.« less

  18. Notch1 Mediates Preconditioning Protection Induced by GPER in Normotensive and Hypertensive Female Rat Hearts.

    PubMed

    Rocca, Carmine; Femminò, Saveria; Aquila, Giorgio; Granieri, Maria C; De Francesco, Ernestina M; Pasqua, Teresa; Rigiracciolo, Damiano C; Fortini, Francesca; Cerra, Maria C; Maggiolini, Marcello; Pagliaro, Pasquale; Rizzo, Paola; Angelone, Tommaso; Penna, Claudia

    2018-01-01

    G protein-coupled estrogen receptor (GPER) is an estrogen receptor expressed in the cardiovascular system. G1, a selective GPER ligand, exerts cardiovascular effects through activation of the PI3K-Akt pathway and Notch signaling in normotensive animals. Here, we investigated whether the G1/GPER interaction is involved in the limitation of infarct size, and improvement of post-ischemic contractile function in female spontaneous hypertensive rat (SHR) hearts. In this model, we also studied Notch signaling and key components of survival pathway, namely PI3K-Akt, nitric oxide synthase (NOS) and mitochondrial K + -ATP (MitoKATP) channels. Rat hearts isolated from female SHR underwent 30 min of global, normothermic ischemia and 120 min of reperfusion. G1 (10 nM) alone or specific inhibitors of GPER, PI3K/NOS and MitoKATP channels co-infused with G1, just before I/R, were studied. The involvement of Notch1 was studied by Western blotting. Infarct size and left ventricular pressure were measured. To confirm endothelial-independent G1-induced protection by Notch signaling, H9c2 cells were studied with specific inhibitor, N -[ N -(3,5 difluorophenacetyl)-L-alanyl]- S -phenylglycine t -butyl ester (DAPT, 5 μM), of this signaling. Using DAPT, we confirmed the involvement of G1/Notch signaling in limiting infarct size in heart of normotensive animals. In the hypertensive model, G1-induced reduction in infarct size and improvement of cardiac function were prevented by the inhibition of GPER, PI3K/NOS, and MitoKATP channels. The involvement of Notch was confirmed by western blot in the hypertensive model and by the specific inhibitor in the normotensive model and cardiac cell line. Our results suggest that GPERs play a pivotal role in mediating preconditioning cardioprotection in normotensive and hypertensive conditions. The G1-induced protection involves Notch1 and is able to activate the survival pathway in the presence of comorbidity. Several pathological conditions, including hypertension, reduce the efficacy of ischemic conditioning strategies. However, G1-induced protection can result in significant reduction of I/R injury also female in hypertensive animals. Further studies may ascertain the clinical translation of the present results.

  19. Loss of PTB or Negative Regulation of Notch mRNA Reveals Distinct Zones of Notch and Actin Protein Accumulation in Drosophila Embryo

    PubMed Central

    Wesley, Cedric S.; Guo, Heng; Chaudhry, Kanita A.; Thali, Markus J.; Yin, Jerry C.; Clason, Todd; Wesley, Umadevi V.

    2011-01-01

    Polypyrimidine Tract Binding (PTB) protein is a regulator of mRNA processing and translation. Genetic screens and studies of wing and bristle development during the post-embryonic stages of Drosophila suggest that it is a negative regulator of the Notch pathway. How PTB regulates the Notch pathway is unknown. Our studies of Drosophila embryogenesis indicate that (1) the Notch mRNA is a potential target of PTB, (2) PTB and Notch functions in the dorso-lateral regions of the Drosophila embryo are linked to actin regulation but not their functions in the ventral region, and (3) the actin-related Notch activity in the dorso-lateral regions might require a Notch activity at or near the cell surface that is different from the nuclear Notch activity involved in cell fate specification in the ventral region. These data raise the possibility that the Drosophila embryo is divided into zones of different PTB and Notch activities based on whether or not they are linked to actin regulation. They also provide clues to the almost forgotten role of Notch in cell adhesion and reveal a role for the Notch pathway in cell fusions. PMID:21750738

  20. The Drosophila T-box transcription factor Midline functions within the Notch-Delta signaling pathway to specify sensory organ precursor cell fates and regulates cell survival within the eye imaginal disc.

    PubMed

    Das, Sudeshna; Chen, Q Brent; Saucier, Joseph D; Drescher, Brandon; Zong, Yan; Morgan, Sarah; Forstall, John; Meriwether, Andrew; Toranzo, Randy; Leal, Sandra M

    2013-01-01

    We report that the T-box transcription factor Midline (Mid), an evolutionary conserved homolog of the vertebrate Tbx20 protein, functions within the Notch-Delta signaling pathway essential for specifying the fates of sensory organ precursor (SOP) cells. These findings complement an established history of research showing that Mid regulates the cell-fate specification of diverse cell types within the developing heart, epidermis and central nervous system. Tbx20 has been detected in unique neuronal and epithelial cells of embryonic eye tissues in both mice and humans. However, the mechanisms by which either Mid or Tbx20 function to regulate cell-fate specification or other critical aspects of eye development including cell survival have not yet been elucidated. We have also gathered preliminary evidence suggesting that Mid may play an indirect, but vital role in selecting SOP cells within the third-instar larval eye disc by regulating the expression of the proneural gene atonal. During subsequent pupal stages, Mid specifies SOP cell fates as a member of the Notch-Delta signaling hierarchy and is essential for maintaining cell viability by inhibiting apoptotic pathways. We present several new hypotheses that seek to understand the role of Mid in regulating developmental processes downstream of the Notch receptor that are critical for specifying unique cell fates, patterning the adult eye and maintaining cellular homeostasis during eye disc morphogenesis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Blockade of Notch3 inhibits the stem-like property and is associated with ALDH1A1 and CD44 via autophagy in non-small lung cancer.

    PubMed

    Ma, Yuanyuan; Li, Mingzhen; Si, Jiahui; Xiong, Ying; Lu, Fangliang; Zhang, Jianzhi; Zhang, Liyi; Zhang, Panpan; Yang, Yue

    2016-06-01

    Acquired resistance to standard chemotherapy causes treatment failure in patients with local advanced and advanced non-small lung cancer (NSCLC). Cancer stem cells (CSCs) are a small subpopulation within cancer that is thought to be resistant to conventional chemotherapy. The Notch pathway is one of the most intensively studied for putative therapeutic targets of CSCs in solid tumors. In our study, suppression of Notch3 decreased colony and sphere formation of stem-like property in lung cancer cells. In addition, Notch3 expression was demonstrated to be upregulated in the patients with chemoresistance and related to poor prognosis of NSCLC patients. Our results also showed that CSC markers ALDH1A1 and CD44 were highly expressed in NSCLC patients with chemoresistance and these two markers were positively correlated with Notch3 expression in lung cancer specimens from TCGA database. Furthermore, the lung cancer cells with drug resistance were shown to be associated with activation of autophagy. All the data support a crucial role of Notch3 in the increase of stem-like property in NSCLC cells that might be associated with upregulation of ALDH1A1 and CD44 and activation of autophagy.

  2. The Curcumin Analog C-150, Influencing NF-κB, UPR and Akt/Notch Pathways Has Potent Anticancer Activity In Vitro and In Vivo

    PubMed Central

    Hackler, László; Ózsvári, Béla; Gyuris, Márió; Sipos, Péter; Fábián, Gabriella; Molnár, Eszter; Marton, Annamária; Faragó, Nóra; Mihály, József; Nagy, Lajos István; Szénási, Tibor; Diron, Andrea; Párducz, Árpád; Kanizsai, Iván; Puskás, László G.

    2016-01-01

    C-150 a Mannich-type curcumin derivative, exhibited pronounced cytotoxic effects against eight glioma cell lines at micromolar concentrations. Inhibition of cell proliferation by C-150 was mediated by affecting multiple targets as confirmed at transcription and protein level. C-150 effectively reduced the transcription activation of NFkB, inhibited PKC-alpha which are constitutively over-expressed in glioblastoma. The effects of C-150 on the Akt/ Notch signaling were also demonstrated in a Drosophila tumorigenesis model. C-150 reduced the number of tumors in Drosophila with similar efficacy to mitoxantrone. In an in vivo orthotopic glioma model, C-150 significantly increased the median survival of treated nude rats compared to control animals. The multi-target action of C-150, and its preliminary in vivo efficacy would render this curcumin analogue as a potent clinical candidate against glioblastoma. PMID:26943907

  3. The Curcumin Analog C-150, Influencing NF-κB, UPR and Akt/Notch Pathways Has Potent Anticancer Activity In Vitro and In Vivo.

    PubMed

    Hackler, László; Ózsvári, Béla; Gyuris, Márió; Sipos, Péter; Fábián, Gabriella; Molnár, Eszter; Marton, Annamária; Faragó, Nóra; Mihály, József; Nagy, Lajos István; Szénási, Tibor; Diron, Andrea; Párducz, Árpád; Kanizsai, Iván; Puskás, László G

    2016-01-01

    C-150 a Mannich-type curcumin derivative, exhibited pronounced cytotoxic effects against eight glioma cell lines at micromolar concentrations. Inhibition of cell proliferation by C-150 was mediated by affecting multiple targets as confirmed at transcription and protein level. C-150 effectively reduced the transcription activation of NFkB, inhibited PKC-alpha which are constitutively over-expressed in glioblastoma. The effects of C-150 on the Akt/ Notch signaling were also demonstrated in a Drosophila tumorigenesis model. C-150 reduced the number of tumors in Drosophila with similar efficacy to mitoxantrone. In an in vivo orthotopic glioma model, C-150 significantly increased the median survival of treated nude rats compared to control animals. The multi-target action of C-150, and its preliminary in vivo efficacy would render this curcumin analogue as a potent clinical candidate against glioblastoma.

  4. Nas transgenic mouse line allows visualization of Notch pathway activity in vivo.

    PubMed

    Souilhol, Céline; Cormier, Sarah; Monet, Marie; Vandormael-Pournin, Sandrine; Joutel, Anne; Babinet, Charles; Cohen-Tannoudji, Michel

    2006-06-01

    The Notch signaling pathway plays multiple and important roles in mammals. However, several aspects of its action, in particular, the precise mapping of its sites of activity, remain unclear. To address this issue, we generated a transgenic line carrying a construct consisting of a nls-lacZ reporter gene under the control of a minimal promoter and multiple RBP-Jkappa binding sites. Here we show that this transgenic line, which we termed NAS (for Notch Activity Sensor), displays an expression profile that is consistent with current knowledge on Notch activity sites in mice, even though it may not report on all these sites. Moreover, we observe that NAS transgene expression is abolished in a RBP-Jkappa-deficient background, indicating that it indeed requires Notch/RBP-Jkappa signaling pathway activity. Thus, the NAS transgenic line constitutes a valuable and versatile tool to gain further insights into the complex and various functions of the Notch signaling pathway.

  5. Leukemogenesis Induced by an Activating β-catenin mutation in Osteoblasts

    PubMed Central

    Kode, Aruna; Manavalan, John S.; Mosialou, Ioanna; Bhagat, Govind; Rathinam, Chozha V.; Luo, Na; Khiabanian, Hossein; Lee, Albert; Vundavalli, Murty; Friedman, Richard; Brum, Andrea; Park, David; Galili, Naomi; Mukherjee, Siddhartha; Teruya-Feldstein, Julie; Raza, Azra; Rabadan, Raul; Berman, Ellin; Kousteni, Stavroula

    2014-01-01

    Summary Cells of the osteoblast lineage affect homing, 1, 2 number of long term repopulating hematopoietic stem cells (HSCs) 3, 4, HSC mobilization and lineage determination and B lymphopoiesis 5-8. More recently osteoblasts were implicated in pre-leukemic conditions in mice 9, 10. Yet, it has not been shown that a single genetic event taking place in osteoblasts can induce leukemogenesis. We show here that in mice, an activating mutation of β-catenin in osteoblasts alters the differentiation potential of myeloid and lymphoid progenitors leading to development of acute myeloid leukemia (AML) with common chromosomal aberrations and cell autonomous progression. Activated β-catenin stimulates expression of the Notch ligand Jagged-1 in osteoblasts. Subsequent activation of Notch signaling in HSC progenitors induces the malignant changes. Demonstrating the pathogenetic role of the Notch pathway, genetic or pharmacological inhibition of Notch signaling ameliorates AML. Nuclear accumulation and increased β-catenin signaling in osteoblasts was also identified in 38% of patients with MDS/AML. These patients showed increased Notch signaling in hematopoietic cells. These findings demonstrate that genetic alterations in osteoblasts can induce AML, identify molecular signals leading to this transformation and suggest a potential novel pharmacotherapeutic approach to AML. PMID:24429522

  6. Evodiamine, a Novel NOTCH3 Methylation Stimulator, Significantly Suppresses Lung Carcinogenesis in Vitro and in Vivo.

    PubMed

    Su, Tao; Yang, Xia; Deng, Jian-Hua; Huang, Qiu-Ju; Huang, Su-Chao; Zhang, Yan-Min; Zheng, Hong-Ming; Wang, Ying; Lu, Lin-Lin; Liu, Zhong-Qiu

    2018-01-01

    Lung cancer is a leading cause of cancer-related deaths worldwide. NOTCH3 signaling is mainly expressed in non-small cell lung carcinoma (NSCLC), and has been proposed as a therapeutic target of NSCLC. While, few agents for preventing or treating NSCLC via targeting NOTCH3 signaling are used in modern clinical practice. Evodiamine (EVO), an alkaloid derived from Euodiae Fructus, possesses low toxicity and has long been shown to exert anti-lung cancer activity. However, the underlying anti-lung cancer mechanisms of EVO are not yet fully understood. In this study, we explored the involvement of NOTCH3 signaling in the anti-lung cancer effects of EVO. Urethane-induced lung cancer mouse model and two NSCLC cell models, A549 and H1299, were used to evaluate the in vivo and in vitro anti-lung cancer action of EVO. A DNA methyltransferase inhibitor was employed to investigate the role of NOTCH3 signaling in the anti-lung cancer effects of EVO. Results showed that EVO potently reduced tumor size and tumor numbers in mice, and inhibited NOTCH3 in the tumors. EVO also dramatically reduced cell viability, induced G2/M cell cycle arrest, inhibited cell migration and reduced stemness in cultured NSCLC cells. Mechanistic studies showed that EVO potently inhibited NOTCH3 signaling by activation of DNMTs-induced NOTCH3 methylation. Importantly, inhibition of NOTCH3 methylation in NSCLC cells diminished EVO's anti-NSCLC effects. Collectively, EVO, a novel NOTCH3 methylation stimulator, exerted potent anti-lung cancer effects partially by inhibiting NOTCH3 signaling. These findings provide new insight into the EVO's anti-NSCLC action, and suggest a potential role of EVO in lung cancer prevention and treatment.

  7. Notch3-specific inhibition using siRNA knockdown or GSI sensitizes paclitaxel-resistant ovarian cancer cells.

    PubMed

    Kang, Haeyoun; Jeong, Ju-Yeon; Song, Ji-Ye; Kim, Tae Heon; Kim, Gwangil; Huh, Jin Hyung; Kwon, Ah-Young; Jung, Sang Geun; An, Hee Jung

    2016-07-01

    Notch signaling plays an important role in ovarian cancer chemoresistance, which is responsible for recurrence. Gamma-secretase inhibitor (GSI) is a broad-spectrum Notch inhibitor, but it has serious side effects. The efficacy of Notch3-specific inhibition in paclitaxel-resistant ovarian cancers was assessed in this study, which has not yet been evaluated relative to GSI. To analyze the effect of Notch3-specific inhibition on paclitaxel-resistant ovarian cancers, we compared cell viability, apoptosis, cell migration, angiogenesis, cell cycle, and spheroid formation after treatment with either Notch3 siRNA or GSI in paclitaxel-resistant SKpac cells and parental SKOV3 cells. Expression levels of survival, cell cycle, and apoptosis-related proteins were measured and compared between groups. Notch3 was significantly overexpressed in chemoresistant cancer tissues and cell lines relative to chemosensitive group. In paclitaxel-resistant cancer cells, Notch inhibition significantly reduced viability, migration, and angiogenesis and increased apoptosis, thereby boosting sensitivity to paclitaxel. Spheroid formation was also significantly reduced. Both Notch3 siRNA-treated cells and GSI-treated cells arrested in the G2/M phase of the cell cycle. Proteins of cell survival, cyclin D1 and cyclin D3 were reduced, whereas p21 and p27 were elevated. Both GSI and Notch3 siRNA treatment reduced expression of anti-apoptotic proteins (BCL-W, BCL2, and BCL-XL) and increased expression of pro-apoptotic proteins (Bad, Bak, Bim, Bid, and Bax). These results indicate that Notch3-specific inhibition sensitizes paclitaxel-resistant cancer cells to paclitaxel treatment, with an efficacy comparable to that of GSI. This approach would be likely to avoid the side effects of broad-spectrum GSI treatment. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  8. Evodiamine, a Novel NOTCH3 Methylation Stimulator, Significantly Suppresses Lung Carcinogenesis in Vitro and in Vivo

    PubMed Central

    Su, Tao; Yang, Xia; Deng, Jian-Hua; Huang, Qiu-Ju; Huang, Su-Chao; Zhang, Yan-Min; Zheng, Hong-Ming; Wang, Ying; Lu, Lin-Lin; Liu, Zhong-Qiu

    2018-01-01

    Lung cancer is a leading cause of cancer-related deaths worldwide. NOTCH3 signaling is mainly expressed in non-small cell lung carcinoma (NSCLC), and has been proposed as a therapeutic target of NSCLC. While, few agents for preventing or treating NSCLC via targeting NOTCH3 signaling are used in modern clinical practice. Evodiamine (EVO), an alkaloid derived from Euodiae Fructus, possesses low toxicity and has long been shown to exert anti-lung cancer activity. However, the underlying anti-lung cancer mechanisms of EVO are not yet fully understood. In this study, we explored the involvement of NOTCH3 signaling in the anti-lung cancer effects of EVO. Urethane-induced lung cancer mouse model and two NSCLC cell models, A549 and H1299, were used to evaluate the in vivo and in vitro anti-lung cancer action of EVO. A DNA methyltransferase inhibitor was employed to investigate the role of NOTCH3 signaling in the anti-lung cancer effects of EVO. Results showed that EVO potently reduced tumor size and tumor numbers in mice, and inhibited NOTCH3 in the tumors. EVO also dramatically reduced cell viability, induced G2/M cell cycle arrest, inhibited cell migration and reduced stemness in cultured NSCLC cells. Mechanistic studies showed that EVO potently inhibited NOTCH3 signaling by activation of DNMTs-induced NOTCH3 methylation. Importantly, inhibition of NOTCH3 methylation in NSCLC cells diminished EVO’s anti-NSCLC effects. Collectively, EVO, a novel NOTCH3 methylation stimulator, exerted potent anti-lung cancer effects partially by inhibiting NOTCH3 signaling. These findings provide new insight into the EVO’s anti-NSCLC action, and suggest a potential role of EVO in lung cancer prevention and treatment. PMID:29765324

  9. Molecular Pathways of Notch Signaling in Vascular Smooth Muscle Cells

    PubMed Central

    Boucher, Joshua; Gridley, Thomas; Liaw, Lucy

    2012-01-01

    Notch signaling in the cardiovascular system is important during embryonic development, vascular repair of injury, and vascular pathology in humans. The vascular smooth muscle cell (VSMC) expresses multiple Notch receptors throughout its life cycle, and responds to Notch ligands as a regulatory mechanism of differentiation, recruitment to growing vessels, and maturation. The goal of this review is to provide an overview of the current understanding of the molecular basis for Notch regulation of VSMC phenotype. Further, we will explore Notch interaction with other signaling pathways important in VSMC. PMID:22509166

  10. YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, Yi-Ting; Ding, Jing-Ya; Li, Ming-Yang

    2012-09-10

    Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model tomore » study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: Black-Right-Pointing-Pointer YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. Black-Right-Pointing-Pointer YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. Black-Right-Pointing-Pointer Knockdown of Gli2 rescues the Yap-overexpression phenotype in P19 cells. Black-Right-Pointing-Pointer Knockdown of Gli2 rescues the Yap-overexpression phenotype in cortical progenitors.« less

  11. Suppression of colon cancer metastasis by Aes through inhibition of Notch signaling.

    PubMed

    Sonoshita, Masahiro; Aoki, Masahiro; Fuwa, Haruhiko; Aoki, Koji; Hosogi, Hisahiro; Sakai, Yoshiharu; Hashida, Hiroki; Takabayashi, Arimichi; Sasaki, Makoto; Robine, Sylvie; Itoh, Kazuyuki; Yoshioka, Kiyoko; Kakizaki, Fumihiko; Kitamura, Takanori; Oshima, Masanobu; Taketo, Makoto Mark

    2011-01-18

    Metastasis is responsible for most cancer deaths. Here, we show that Aes (or Grg5) gene functions as an endogenous metastasis suppressor. Expression of Aes was decreased in liver metastases compared with primary colon tumors in both mice and humans. Aes inhibited Notch signaling by converting active Rbpj transcription complexes into repression complexes on insoluble nuclear matrix. In tumor cells, Notch signaling was triggered by ligands on adjoining blood vessels, and stimulated transendothelial migration. Genetic depletion of Aes in Apc(Δ716) intestinal polyposis mice caused marked tumor invasion and intravasation that were suppressed by Notch signaling inhibition. These results suggest that inhibition of Notch signaling can be a promising strategy for prevention and treatment of colon cancer metastasis. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Notch3 Interactome Analysis Identified WWP2 as a Negative Regulator of Notch3 Signaling in Ovarian Cancer

    PubMed Central

    Guan, Bin; Wu, Ren-Chin; Zhu, Heng; Blackshaw, Seth; Shih, Ie-Ming; Wang, Tian-Li

    2014-01-01

    The Notch3 signaling pathway is thought to play a critical role in cancer development, as evidenced by the Notch3 amplification and rearrangement observed in human cancers. However, the molecular mechanism by which Notch3 signaling contributes to tumorigenesis is largely unknown. In an effort to identify the molecular modulators of the Notch3 signaling pathway, we screened for Notch3-intracellular domain (N3-ICD) interacting proteins using a human proteome microarray. Pathway analysis of the Notch3 interactome demonstrated that ubiquitin C was the molecular hub of the top functional network, suggesting the involvement of ubiquitination in modulating Notch3 signaling. Thereby, we focused on functional characterization of an E3 ubiquitin-protein ligase, WWP2, a top candidate in the Notch3 interactome list. Co-immunoprecipitation experiments showed that WWP2 interacted with N3-ICD but not with intracellular domains from other Notch receptors. Wild-type WWP2 but not ligase-deficient mutant WWP2 increases mono-ubiquitination of the membrane-tethered Notch3 fragment, therefore attenuating Notch3 pathway activity in cancer cells and leading to cell cycle arrest. The mono-ubiquitination by WWP2 may target an endosomal/lysosomal degradation fate for Notch3 as suggested by the fact that the process could be suppressed by the endosomal/lysosomal inhibitor. Analysis of The Cancer Genome Atlas dataset showed that the majority of ovarian carcinomas harbored homozygous or heterozygous deletions in WWP2 locus, and there was an inverse correlation in the expression levels between WWP2 and Notch3 in ovarian carcinomas. Furthermore, ectopic expression of WWP2 decreased tumor development in a mouse xenograft model and suppressed the Notch3-induced phenotypes including increase in cancer stem cell-like cell population and platinum resistance. Taken together, our results provide evidence that WWP2 serves as a tumor suppressor by negatively regulating Notch3 signaling in ovarian cancer. PMID:25356737

  13. The role of the Hes1 crosstalk hub in Notch-Wnt interactions of the intestinal crypt

    PubMed Central

    Harrington, Heather A.; Dale, Trevor; Gavaghan, David J.

    2017-01-01

    The Notch pathway plays a vital role in determining whether cells in the intestinal epithelium adopt a secretory or an absorptive phenotype. Cell fate specification is coordinated via Notch’s interaction with the canonical Wnt pathway. Here, we propose a new mathematical model of the Notch and Wnt pathways, in which the Hes1 promoter acts as a hub for pathway crosstalk. Computational simulations of the model can assist in understanding how healthy intestinal tissue is maintained, and predict the likely consequences of biochemical knockouts upon cell fate selection processes. Chemical reaction network theory (CRNT) is a powerful, generalised framework which assesses the capacity of our model for monostability or multistability, by analysing properties of the underlying network structure without recourse to specific parameter values or functional forms for reaction rates. CRNT highlights the role of β-catenin in stabilising the Notch pathway and damping oscillations, demonstrating that Wnt-mediated actions on the Hes1 promoter can induce dynamic transitions in the Notch system, from multistability to monostability. Time-dependent model simulations of cell pairs reveal the stabilising influence of Wnt upon the Notch pathway, in which β-catenin- and Dsh-mediated action on the Hes1 promoter are key in shaping the subcellular dynamics. Where Notch-mediated transcription of Hes1 dominates, there is Notch oscillation and maintenance of fate flexibility; Wnt-mediated transcription of Hes1 favours bistability akin to cell fate selection. Cells could therefore regulate the proportion of Wnt- and Notch-mediated control of the Hes1 promoter to coordinate the timing of cell fate selection as they migrate through the intestinal epithelium and are subject to reduced Wnt stimuli. Furthermore, mutant cells characterised by hyperstimulation of the Wnt pathway may, through coupling with Notch, invert cell fate in neighbouring healthy cells, enabling an aberrant cell to maintain its neighbours in mitotically active states. PMID:28245235

  14. Effects of {gamma}-secretase inhibition on the proliferation and vitamin D{sub 3} induced osteogenesis in adipose derived stem cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jing, Wei; Xiong, Zhonghua; Cai, Xiaoxiao

    2010-02-12

    As a {gamma}-secretase inhibitor, DAPT has been widely used to evaluate the biological behaviors and Notch signaling pathway in various cells. This study was aimed to examine the effects of DAPT on the growth and vitamin D{sub 3} induced osteogenesis in adipose derived stem cells (ASCs). The cells were treated with or without DAPT and induced to osteoblastic lineage in the presence of vitamin D{sub 3}. Alizarin red staining and real-time PCR results indicated that the addition of DAPT to vitamin D{sub 3} treatments enhanced osteogenesis in ASCs. According to the fold increase and colony-forming unit assay results, the cellsmore » cultured in DAPT exhibited lower proliferation rate than those cultured in control medium. Hey1, expressed in the nucleus of ASCs to act as a transcriptional repressor, was downregulated when Notch signaling was inhibited by DAPT. Whereas the expression of Runx2 increased in the nucleus of osteogenic induced ASCs after DAPT treatment. This study demonstrated that DAPT reduced the proliferation and enhanced the osteogenesis in ASCs via regulation of Notch and Runx2 expression.« less

  15. Notch inhibition counteracts Paneth cell death in absence of caspase-8.

    PubMed

    Jeon, M K; Kaemmerer, E; Schneider, U; Schiffer, M; Klaus, C; Hennings, J; Clahsen, T; Ackerstaff, T; Niggemann, M; Schippers, A; Longerich, T; Sellge, G; Trautwein, C; Wagner, N; Liedtke, C; Gassler, N

    2018-05-16

    Opposing activities of Notch and Wnt signaling regulate mucosal barrier homeostasis and differentiation of intestinal epithelial cells. Specifically, Wnt activity is essential for differentiation of secretory cells including Wnt3-producing Paneth cells, whereas Notch signaling strongly promotes generation of absorptive cells. Loss of caspase-8 in intestinal epithelium (casp8 ∆int ) is associated with fulminant epithelial necroptosis, severe Paneth cell death, secondary intestinal inflammation, and an increase in Notch activity. Here, we found that pharmacological Notch inhibition with dibenzazepine (DBZ) is able to essentially rescue the loss of Paneth cells, deescalate the inflammatory phenotype, and reduce intestinal permeability in casp8 ∆int mice. The secretory cell metaplasia in DBZ-treated casp8 ∆int animals is proliferative, indicating for Notch activities partially insensitive to gamma-secretase inhibition in a casp8 ∆int background. Our data suggest that casp8 acts in the intestinal Notch network.

  16. Endodermal Hedgehog signals modulate Notch pathway activity in the developing digestive tract mesenchyme

    PubMed Central

    Kim, Tae-Hee; Kim, Byeong-Moo; Mao, Junhao; Rowan, Sheldon; Shivdasani, Ramesh A.

    2011-01-01

    The digestive tract epithelium and its adjoining mesenchyme undergo coordinated patterning and growth during development. The signals they exchange in the process are not fully characterized but include ligands of the Hedgehog (Hh) family, which originate in the epithelium and are necessary for mesenchymal cells to expand in number and drive elongation of the developing gut tube. The Notch signaling pathway has known requirements in fetal and adult intestinal epithelial progenitors. We detected Notch pathway activity in the embryonic gut mesenchyme and used conditional knockout mice to study its function. Selective disruption of the Notch effector gene RBP-Jκ (Rbpj) in the mesenchyme caused progressive loss of subepithelial fibroblasts and abbreviated gut length, revealing an unexpected requirement in this compartment. Surprisingly, constitutive Notch activity also induced rapid mesenchymal cell loss and impaired organogenesis, probably resulting from increased cell death and suggesting the need for a delicate balance in Notch signaling. Because digestive tract anomalies in mouse embryos with excess Notch activity phenocopy the absence of Hh signaling, we postulated that endodermal Hh restrains mesenchymal Notch pathway activity. Indeed, Hh-deficient embryos showed Notch overactivity in their defective gut mesenchyme and exposure to recombinant sonic hedgehog could override Notch-induced death of cultured fetal gut mesenchymal cells. These results reveal unexpected interactions between prominent signals in gastrointestinal development and provide a coherent explanation for Hh requirements in mesenchymal cell survival and organ growth. PMID:21750033

  17. Metformin affects the features of a human hepatocellular cell line (HepG2) by regulating macrophage polarization in a co-culture microenviroment.

    PubMed

    Chen, Miaojiao; Zhang, Jingjing; Hu, Fang; Liu, Shiping; Zhou, Zhiguang

    2015-11-01

    Accumulating evidence suggests an association between diabetes and cancer. Inflammation is a key event that underlies the pathological processes of the two diseases. Metformin displays anti-cancer effects, but the mechanism is not completely clear. This study investigated whether metformin regulated the microenvironment of macrophage polarization to affect the characteristics of HepG2 cells and the possible role of the Notch-signalling pathway. RAW264.7 macrophages were cultured alone or co-cultured with HepG2 cells and treated with metformin. We analysed classical (M1) and alternative (M2) gene expression in RAW264.7 cells using quantitative real-time polymerase chain reaction. Changes in mRNA and protein expressions of Notch signalling in both cell types were also detected using quantitative real-time polymerase chain reaction and Western-blotting analyses. The proliferation, apoptosis and migration of HepG2 cells were detected using Cell Titer 96 AQueous One Solution Cell Proliferation Assay (MTS) (Promega Corporation, Fitchburg, WI, USA), Annexin V-FITC/PI (7SeaPharmTech, Shanghai, China) and the cell scratch assay, respectively. Metformin induced single-cultured RAW264.7 macrophages with an M2 phenotype but attenuated the M2 macrophage differentiation and inhibited monocyte chemoattractant protein-1 (MCP-1) secretion in a co-culture system. The co-cultured group of metformin pretreatment activated Notch signalling in macrophages but repressed it inHepG2 cells. Co-culture also promoted the proliferation and migration of HepG2 cells. However, along with the enhanced apoptosis, the proliferation and the migration of HepG2 cells were remarkably inhibited in another co-culture system with metformin pretreatment. Metformin can skew RAW264.7 macrophages toward different phenotypes according to changes in the microenvironment, which may affect the inflammatory conditions mediated by macrophages, induce apoptosis and inhibit the proliferation and migration of HepG2 cells. Notch signalling pathway is a potentially important mechanism in the regulation of metformin on macrophage polarization and the subsequent change of hepatoma cells. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Notch 1 Receptor, Delta 1 Ligand and HES 1 Transcription Factor are Expressed in the Lining Epithelium of Periapical Cysts (Preliminary Study).

    PubMed

    Meliou, E; Kerezoudis, Np; Tosios, Ki; Kiaris, H

    2010-07-27

    Periapical cyst is a chronic inflammatory disorder of periradicular tissues. The precise pathological mechanisms involved in periapical cyst enlargement remain unclear. Notch signaling is an evolutionarily conserved pathway with a regulatory role in cell fate decisions during development and in carcinogenesis. To date, there are no published data available on the expression of Notch signaling components in periapical cysts or any other jaw cyst. In this immunohistochemical study we have examined the expression of the receptor Notch 1, the ligand Delta 1 and the transcription factor HES 1 in the epithelium of well defined periapical cysts. Immunostaining reaction of Notch 1, Delta 1 and HES 1 was observed in the cytoplasm and/or the cytoplasmic membrane and occasionally in the nucleus in the majority of epithelial cells of all periapical cysts. The present observations indicate that Notch pathway is active in the epithelium of periapical cysts. It can be speculated that activation of epithelial cells of periapical cysts is associated with activation of Notch pathway and imply involvement of this pathway in periapical cyst growth and expansion.

  19. tortuga refines Notch pathway gene expression in the zebrafish presomitic mesoderm at the post-transcriptional level.

    PubMed

    Dill, Kariena K; Amacher, Sharon L

    2005-11-15

    We have identified the zebrafish tortuga (tor) gene by an ENU-induced mutation that disrupts the presomitic mesoderm (PSM) expression of Notch pathway genes. In tor mutants, Notch pathway gene expression persists in regions of the PSM where expression is normally off in wild type embryos. The expression of hairy/Enhancer of split-related 1 (her1) is affected first, followed by the delta genes deltaC and deltaD, and finally, by another hairy/Enhancer of split-related gene, her7. In situ hybridization with intron-specific probes for her1 and deltaC indicates that transcriptional bursts of expression are normal in tor mutants, suggesting that tor normally functions to refine her1 and deltaC message levels downstream of transcription. Despite the striking defects in Notch pathway gene expression, somite boundaries form normally in tor mutant embryos, although somitic mesoderm defects are apparent later, when cells mature to form muscle fibers. Thus, while the function of Notch pathway genes is required for proper somite formation, the tor mutant phenotype suggests that precise oscillations of Notch pathway transcripts are not essential for establishing segmental pattern in the presomitic mesoderm.

  20. Notch Inhibitors for Cancer Treatment

    PubMed Central

    Espinoza, Ingrid; Miele, Lucio

    2013-01-01

    Notch signaling is an evolutionarily conserved cell signaling pathway involved in cell fate during development, stem cell renewal and differentiation in postnatal tissues. Roles for Notch in carcinogenesis, in the biology of cancer stem cells and tumor angiogenesis have been reported. These features identify Notch as a potential therapeutic target in oncology. Based on the molecular structure of Notch receptor, Notch ligands and Notch activators, a set of Notch pathway inhibitors have been developed. Most of these inhibitors had shown anti-tumor effects in preclinical studies. At the same time, the combinatorial effect of these inhibitors with current chemotherapeutical drugs still under study in different clinical trials. In this review, we describe the basics of Notch signaling and the role of Notch in normal and cancer stem cells as a logic way to develop different Notch inhibitors and their current stage of progress for cancer patient’s treatment. PMID:23458608

  1. Targeting Notch, Hedgehog, and Wnt pathways in cancer stem cells: clinical update

    PubMed Central

    Miele, Lucio; Harris, Pamela Jo; Jeong, Woondong; Bando, Hideaki; Kahn, Michael; Yang, Sherry X.

    2015-01-01

    During the past decade, cancer stem cells (CSCs) have been increasingly identified in many malignancies. Although the origin and plasticity of these cells remain controversial, tumour heterogeneity and the presence of small populations of cells with stem-like characteristics is established in most malignancies. CSCs display many features of embryonic or tissue stem cells, and typically demonstrate persistent activation of one or more highly conserved signal transduction pathways involved in development and tissue homeostasis, including the Notch, Hedgehog (HH), and Wnt pathways. CSCs generally have slow growth rates and are resistant to chemotherapy and/or radiotherapy. Thus, new treatment strategies targeting these pathways to control stem-cell replication, survival and differentiation are under development. Herein, we provide an update on the latest advances in the clinical development of such approaches, and discuss strategies for overcoming CSC-associated primary or acquired resistance to cancer treatment. Given the crosstalk between the different embryonic developmental signalling pathways, as well as other pathways, designing clinical trials that target CSCs with rational combinations of agents to inhibit possible compensatory escape mechanisms could be of particular importance. We also share our views on the future directions for targeting CSCs to advance the clinical development of these classes of agents. PMID:25850553

  2. From Fly Wings to Targeted Cancer Therapies: A Centennial for Notch Signaling

    PubMed Central

    Ntziachristos, Panagiotis; Lim, Jing Shan; Sage, Julien; Aifantis, Iannis

    2014-01-01

    Since Notch phenotypes in Drosophila melanogaster were identified 100 years, Notch signaling has been extensively characterized as a regulator of cell fate decisions in a variety of organisms and tissues. However, in the past 20 years, accumulating evidence has linked alterations in the Notch pathway to tumorigenesis. In this Perspective, we discuss the pro-tumorigenic and tumor suppressive functions of Notch signaling and dissect the molecular mechanisms that underlie these functions in hematopoietic cancers and solid tumors. Finally, we link these mechanisms and observations to possible therapeutic strategies targeting the Notch pathway in human cancers. PMID:24651013

  3. [Effect of CP Metronomic Chemotherapy on RPMI 8226 Cell Proli-feration and Notch1/NF-κB Signaling Pathway In Vitro].

    PubMed

    Guo, Lie-Ping; Zhou, Fan; Shi, Hao-Tian; Chen, Hai-Min; Lin, Chen-Hui; Chen, Xiao-Ling; Hou, Jian

    2016-10-01

    To investigate the effect of metronomic chemotherapy of low dose phosphoramide combined with prednisolone (CP metronomic chemotherapy) on proliferation and apoptosis of RPMI 8226 cells, and to explore its regulating effect on Notch1/NF-κB signaling pathways. Experiment was divided into the DMSO control group, and the phosphoramide mustard (PM) group, the prednisolone group, the phosphoramide mustard plus prednisolone group (the CP group). RPMI 8226 cells were treated with different drugs, CCK-8 method was used to detect cell proliferation, flow cytometry was used to detect the cell cycle and apoptosis, reverse transcription PCR was used to detect Notch1 and NF-κB mRNA expression level. Compared with DMSO control group, RPMI8226 cell proliferation inhibition rate in all the PM, prednisolone and CP groups increased significantly with prolonging of time (r of 0.994,0.996,0.999, respectively, P<0.001). And at the same time, the inhibitory rate of cell proliferation was significantly different; the cell inhibitory rate in PM group was lowest, that in CP group was highgest, that in prednissone group was intermediate (P<0.01). After 48 hours, compared with the DMSO control group, the G 1 /G 0 cell proportion in treatment group increased significantly, S phase cell proportion decreased significantly, especially in PM and CP groups. The G 2 /M phase cell proportion increased in PM group, while reduced in the prednisolone and the CP groups. After 48 hours, compared with the DMSO control group, RPMI 8226 cell apoptosis rate increased as follow: in PM, pre-dnisolone and CP group(P<0.01). After 48 hours, compared with the DMSO control group, Notch1 and NF-κB mRNA expression in the prednisolone, the PM and the CP group decreased significantly(P<0.001). CP metronomic chemotherapy can significantly reduce RPMI 8226 cell proliferation, promote RPMI 8226 cell apoptosis, arrest RPMI 8226 cells mainly in the G 1 /G 0 phase, and significantly reduce Notch1 and NF-κB expression levels. It is suggested that Notch1/NF-κB signaling pathways is involved in CP metronomic chemotherapy for MM.

  4. Nas transgenic mouse line allows visualization of Notch pathway activity in vivo

    PubMed Central

    Souilhol, Céline; Cormier, Sarah; Monet, Marie; Vandormael-Pournin, Sandrine; Joutel, Anne; Babinet, Charles; Cohen-Tannoudji, Michel

    2006-01-01

    The Notch signalling pathway plays multiple and important roles in mammals. However, several aspects of its action, in particular the precise mapping of its sites of activity, remain unclear. To address this issue, we have generated a transgenic line carrying a construct consisting of a nls-lacZ reporter gene under the control of a minimal promoter and multiple RBP-Jκ binding sites. Here we show that this transgenic line, we named NAS for Notch Activity Sensor, displays an expression profile that is consistent with current knowledge on Notch activity sites in mice, even though it may not report on all these sites. Moreover, we observe that NAS transgene expression is abolished in a RBP-Jκ deficient background indicating that it indeed requires Notch/RBP-Jκ signalling pathway activity. Thus, the NAS transgenic line constitutes a valuable and versatile tool to gain further insights into the complex and various functions of the Notch signalling pathway. PMID:16708386

  5. Shengui Sansheng San extraction is an angiogenic switch via regulations of AKT/mTOR, ERK1/2 and Notch1 signal pathways after ischemic stroke.

    PubMed

    Liu, Bowen; Luo, Cheng; Zheng, Zhaoguang; Xia, Zhenyan; Zhang, Qian; Ke, Chienchih; Liu, Renshyan; Zhao, Yonghua

    2018-05-15

    As a traditional Chinese herbal formula, Shengui Sansheng San (SSS) has been employed for stroke treatment more than 300 years. We hypothesize that SSS extraction is an angiogenic switch in penumbra post-stroke, and corresponding mechanisms are investigated. In present study, rats were subjected to permanent middle cerebral artery occlusion model (MCAo) and were treated with low, middle and high doses of SSS extraction. We assessed neurological function and survival rate, and measured infarct volume by 2,3,5-triphenyltetrazolium chloride staining on day 7 after ischemia. von Willebrand factor (vWF), stromal cell-derived factor-1 alpha (SDF-1α) /chemokine (C-X-C motif) receptor 4 (CXCR4) axis, vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) as well as protein kinase B (AKT)/mammalian target of rapamycin (mTOR) /hypoxia-inducible factor-1 alpha (HIF-1α), extracellular signal-regulated kinase 1/2 (ERK1/2) and Notch1 signaling pathways were respectively investigated by immunofluorescence assay or western blotting in vivo and oxygen-glucose-deprived (OGD) brain microvascular endothelial cells (BMECs); simultaneously, wound healing of BMECs and tube formation assay were administrated. Compared to MCAo group, SSS extraction could significantly improve neurological functional scores, survival rate and cerebral infarct volume, enhance vWF + vascular density and perimeter, SDF-1α/CXCR4 axis, VEGF expression, as well as activate AKT/mTOR/HIF-1α and ERK1/2 and inhibit Notch1 pathways in penumbra. In vitro, containing SSS extraction serum increased BMEC migration, capillary formation and VEGF expression via up-regulations of AKT/mTOR and ERK1/2 pathways in OGD BMECs, but ERK inhibitor (U0126) reversed the result of VEGF expression in high dose of SSS group. Additionally, VEGFR2 and Notch1 expressions were suppressed by containing SSS extraction serum. All results were in dose dependent manner. Our study firstly demonstrates that SSS extraction is an angiogenic switch. Due to suppressed VEGFR2/Notch1 cascades and activated AKT/mTOR and ERK1/2 signals in BMECs, a feedback loop of angiogenic homeostasis is established. Furthermore, the comprehensive mediations of SDF-1α/CXCR4 axis, AKT/mTOR/HIF-α, ERK1/2 and Notch1 pathways in penumbra contribute to the improvements of neurological function, survival rate and infarct volume post-stroke. Copyright © 2018 Elsevier GmbH. All rights reserved.

  6. Minocycline attenuates the development of diabetic neuropathy by inhibiting spinal cord Notch signaling in rat.

    PubMed

    Yang, Cheng; Gao, Jie; Wu, Banglin; Yan, Nuo; Li, Hui; Ren, Yiqing; Kan, Yufei; Liang, Jiamin; Jiao, Yang; Yu, Yonghao

    2017-10-01

    We studied the effects of minocycline (an inhibitor of microglial activation) on the expression and activity of Notch-1 receptor, and explored the therapeutic efficacy of minocycline combined with Notch inhibitor DAPT in the treatment of diabetic neuropathic pain (DNP). Diabetic rat model was established by intraperitoneal injection (ip) of Streptozotocin (STZ). Expression and activity of Notch-1 and expression of macrophage/microglia marker Iba-1 were detected by WB. Diabetes induction significantly attenuated sciatic nerve conduction velocity, and dramatically augmented the expression and the activity of Notch-1 in the lumbar enlargement of the spinal cord. Minocycline treatment, however, accelerated the decreased conduction velocity of sciatic nerve and suppressed Notch-1expression and activity in diabetic rats. Similar to DAPT treatment, minocycline administration also prolonged thermal withdrawal latency (TWL) and increase mechanical withdrawal threshold (MWT) in diabetic rats in response to heat or mechanical stimulation via inhibition the expression and the activity of Notch-1 in spinal cord. Combination of DAPT and minocycline further inhibited Notch-1 receptor signaling and reduce neuropathic pain exhibited as improved TWL and MWT. Our study revealed a novel mechanism of Notch-1 receptor inhibition in spinal cord induced by minocycline administration, and suggested that the combination of minocycline and DAPT has the potential to treat DNP. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. [Killing effect of Huaier combined with DC-CIK on nude mice bearing colon cancer HT29 stem cells in vivo].

    PubMed

    Sun, Wen-Wen; Dou, Jin-Xia; Zhang, Lin; Qiao, Li-Kui; Shen, Na; Gao, Wen-Yuan

    2018-01-01

    To compare the therapeutic effects of different treatment methods on the nude mice bearing colon cancer HT29 cells. BalB/C nude mice colon cancer stem cell models were established and randomly divided into the following four groups, with 8 nude mice in each group: blank control group, DC-CIK group, Huaier group, and Huaier combined with DC-CIK group (combined treatment group). The mice in DC-CIK group and combined treatment group received 1×10⁶ DC-CIK cells treatment by tail vein injectionafter the tumor stem cells were inoculated for 4 days,2 times a week for three weeks. The mice in Huaier group and combined treatment group received intragastric administration at the dose of 20 g/60 kg body weight, 0.2 mL/time, once a day for a total of three weeks. The mice in control group received equal volume of normal saline. Tumor size and body weight of nude mice were measured every 2 days during treatment for three weeks in each group. After the treatment, the nude mice were sacrificed to measure the tumor weight and the tumor inhibition rate was calculated. The RT-PCR method was used to detect the expression levels of the key genes in the signal pathway. After the end of the treatment, the quality of the tumor in the Huaier group, DC-CIK group and combined treatment group was significantly lower than that in the control group; the quality in combined treatment group was significantly lower than that in Huaier group and DC-CIK group.Among them, the tumor inhibition rate reached 46.77% in the combined treatment group. In respect of changes in expression levels of key genes in the signaling pathway, the mRNA expression levels of key genes PI3KR1 and Akt in PI3K/Akt pathway, key genes Wnt1 and CTTNB1 in Wnt/ β -catenin pathway, and key genes Notch1, Notch2, Notch3 in Notch pathway in the combined treatment group were lower than those in DC-CIK group and Huaier group. The Huaier combined with DC-CIK group showed best therapeutic effect among different treatment methods for HT29 stemcell colon tumors in nude mice, providing a new idea for clinical treatment of colon cancer. Copyright© by the Chinese Pharmaceutical Association.

  8. BCL6 antagonizes NOTCH2 to maintain survival of human follicular lymphoma cells

    PubMed Central

    Valls, Ester; Lobry, Camille; Geng, Huimin; Wang, Ling; Cardenas, Mariano; Rivas, Martín; Cerchietti, Leandro; Oh, Philmo; Yang, Shao Ning; Oswald, Erin; Graham, Camille W.; Jiang, Yanwen; Hatzi, Katerina; Agirre, Xabier; Perkey, Eric; Li, Zhuoning; Tam, Wayne; Bhatt, Kamala; Leonard, John P.; Zweidler-McKay, Patrick A.; Maillard, Ivan; Elemento, Olivier; Ci, Weimin; Aifantis, Iannis; Melnick, Ari

    2017-01-01

    Summary Although the BCL6 transcriptional repressor is frequently expressed in human follicular lymphomas (FL), its biological role in this disease remains unknown. Herein we comprehensively identify the set of gene promoters directly targeted by BCL6 in primary human FLs. We noted that BCL6 binds and represses NOTCH2 and Notch pathway genes. Moreover, BCL6 and NOTCH2 pathway gene expression is inversely correlated in FL. Notably BCL6 up-regulation is associated with repression of Notch2 and its target genes in primary human and murine germinal center cells. Repression of Notch2 is an essential function of BCL6 in FL and GC B-cells since inducible expression of Notch2 abrogated GC formation in mice and kills FL cells. Indeed BCL6-targeting compounds or gene silencing leads to the induction of NOTCH2 activity and compromises survival of FL cells whereas NOTCH2 depletion or pathway antagonists rescue FL cells from such effects. Moreover, BCL6 inhibitors induced NOTCH2 expression and suppressed growth of human FL xenografts in vivo and primary human FL specimens ex vivo. These studies suggest that established FLs are thus dependent on BCL6 through its suppression of NOTCH2. PMID:28232365

  9. Primary cilia maintain corneal epithelial homeostasis by regulation of the Notch signaling pathway

    PubMed Central

    Grisanti, Laura; Revenkova, Ekaterina; Gordon, Ronald E.

    2016-01-01

    Primary cilia have been linked to signaling pathways involved in cell proliferation, cell motility and cell polarity. Defects in ciliary function result in developmental abnormalities and multiple ciliopathies. Patients affected by severe ciliopathies, such as Meckel syndrome, present several ocular surface disease conditions of unclear pathogenesis. Here, we show that primary cilia are predominantly present on basal cells of the mouse corneal epithelium (CE) throughout development and in the adult. Conditional ablation of cilia in the CE leads to an increase in proliferation and vertical migration of basal corneal epithelial cells (CECs). A consequent increase in cell density of suprabasal layers results in a thicker than normal CE. Surprisingly, in cilia-deficient CE, cilia-mediated signaling pathways, including Hh and Wnt pathways, were not affected but the intensity of Notch signaling was severely diminished. Although Notch1 and Notch2 receptors were expressed normally, nuclear Notch1 intracellular domain (N1ICD) expression was severely reduced. Postnatal development analysis revealed that in cilia-deficient CECs downregulation of the Notch pathway precedes cell proliferation defects. Thus, we have uncovered a function of the primary cilium in maintaining homeostasis of the CE by balancing proliferation and vertical migration of basal CECs through modulation of Notch signaling. PMID:27122169

  10. Cartilage-specific RBPjκ-dependent and -independent Notch signals regulate cartilage and bone development

    PubMed Central

    Kohn, Anat; Dong, Yufeng; Mirando, Anthony J.; Jesse, Alana M.; Honjo, Tasuku; Zuscik, Michael J.; O’Keefe, Regis J.; Hilton, Matthew J.

    2012-01-01

    The Notch signaling pathway has emerged as an important regulator of endochondral bone formation. Although recent studies have examined the role of Notch in mesenchymal and chondro-osteo progenitor cell populations, there has yet to be a true examination of Notch signaling specifically within developing and committed chondrocytes, or a determination of whether cartilage and bone formation are regulated via RBPjκ-dependent or -independent Notch signaling mechanisms. To develop a complete understanding of Notch signaling during cartilage and bone development we generated and compared general Notch gain-of-function (Rosa-NICDf/+), RBPjκ-deficient (Rbpjκf/f), and RBPjκ-deficient Notch gain-of-function (Rosa-NICDf/+;Rbpjκf/f) conditional mutant mice, where activation or deletion of floxed alleles were specifically targeted to mesenchymal progenitors (Prx1Cre) or committed chondrocytes (inducible Col2CreERT2). These data demonstrate, for the first time, that Notch regulation of chondrocyte maturation is solely mediated via the RBPjκ-dependent pathway, and that the perichodrium or osteogenic lineage probably influences chondrocyte terminal maturation and turnover of the cartilage matrix. Our study further identifies the cartilage-specific RBPjκ-independent pathway as crucial for the proper regulation of chondrocyte proliferation, survival and columnar chondrocyte organization. Unexpectedly, the RBPjκ-independent Notch pathway was also identified as an important long-range cell non-autonomous regulator of perichondral bone formation and an important cartilage-derived signal required for coordinating chondrocyte and osteoblast differentiation during endochondral bone development. Finally, cartilage-specific RBPjκ-independent Notch signaling likely regulates Ihh responsiveness during cartilage and bone development. PMID:22354840

  11. Effect of verteporfin-PDT on the Notch signaling pathway in cholangiocarcinoma (CCA) cell lines

    NASA Astrophysics Data System (ADS)

    Cerec, Virginie; Andreola, Fausto; Pereira, Stephen P.

    2009-06-01

    Accumulating preclinical and clinical evidence supports a pro-oncogenic function for Notch signaling in several solid tumors. Therefore, Notch inhibitory agents, such as gamma-secretase inhibitors (GSI), are being investigated as cancer therapeutic agents and a potential adjuvant to conventional chemo/radiotherapy. To date, no in vitro data are available on the cellular response and effect of either photodynamic therapy (PDT) or GSI on human cholangiocarcinoma (CCA). Consequently, we aimed to study the: (i) constitutive expression of Notch signaling pathway in CCA cell lines; (ii) response to Verteporfin-PDT and to GSI, as single agents on CCA cell lines; (iii) effect of Verteporfin-PDT on Notch signaling pathway expression. Expression of Notch signaling components was studied in two cholangiocarcinoma cell lines, HuCCT1 and TFK-1 (intra- and extrahepatic, respectively). No difference in basal expression of Notch1, 2 and Jagged1 was observed in either cell line. In contrast, Notch3 was found to be weakly and highly expressed in HuCCT1 and TFK-1 cells, respectively - supporting our recent microarray data which showed Notch3 overexpression in biliary brushings from patients with extrahepatic CCA. HuCCT1 and TFK-1 differentially responded to Verteporfin-PDT treatment; preliminary data showed no clear effect of GSI on proliferation/apoptosis in either cell line following short exposure (6 and 24h). Following Verteporfin-PDT, Notch1, 2 and Jagged-1 expression was down-regulated in both cell lines, while Notch3 expression was unaffected in HuCCT1 cells and down-regulated in TFK-1 cells. The Notch signaling pathway could represent a potential target for combination therapy in CCA treatment.

  12. Human papillomavirus 16E6 and NFX1-123 potentiate notch signaling and differentiation without activating cellular arrest

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vliet-Gregg, Portia A.; Hamilton, Jennifer R.; Katzenellenbogen, Rachel A., E-mail: rkatzen@uw.edu

    High-risk human papillomavirus (HR HPV) oncoproteins bind host cell proteins to dysregulate and uncouple apoptosis, senescence, differentiation, and growth. These pathways are important for both the viral life cycle and cancer development. HR HPV16 E6 (16E6) interacts with the cellular protein NFX1-123, and they collaboratively increase the growth and differentiation master regulator, Notch1. In 16E6 expressing keratinocytes (16E6 HFKs), the Notch canonical pathway genes Hes1 and Hes5 were increased with overexpression of NFX1-123, and their expression was directly linked to the activation or blockade of the Notch1 receptor. Keratinocyte differentiation genes Keratin 1 and Keratin 10 were also increased, butmore » in contrast their upregulation was only indirectly associated with Notch1 receptor stimulation and was fully unlinked to growth arrest, increased p21{sup Waf1/CIP1}, or decreased proliferative factor Ki67. This leads to a model of 16E6, NFX1-123, and Notch1 differently regulating canonical and differentiation pathways and entirely uncoupling cellular arrest from increased differentiation. - Highlights: • 16E6 and NFX1-123 increased the Notch canonical pathway through Notch1. • 16E6 and NFX1-123 increased the differentiation pathway indirectly through Notch1. • 16E6 and NFX1-123 increased differentiation gene expression without growth arrest. • Increased NFX1-123 with 16E6 may create an ideal cellular phenotype for HPV.« less

  13. Protein Kinase Cι Drives a NOTCH3-dependent Stem-like Phenotype in Mutant KRAS Lung Adenocarcinoma.

    PubMed

    Ali, Syed A; Justilien, Verline; Jamieson, Lee; Murray, Nicole R; Fields, Alan P

    2016-03-14

    We report that the protein kinase Cι (PKCι) oncogene controls expression of NOTCH3, a key driver of stemness, in KRAS-mediated lung adenocarcinoma (LADC). PKCι activates NOTCH3 expression by phosphorylating the ELF3 transcription factor and driving ELF3 occupancy on the NOTCH3 promoter. PKCι-ELF3-NOTCH3 signaling controls the tumor-initiating cell phenotype by regulating asymmetric cell division, a process necessary for tumor initiation and maintenance. Primary LADC tumors exhibit PKCι-ELF3-NOTCH3 signaling, and combined pharmacologic blockade of PKCι and NOTCH synergistically inhibits tumorigenic behavior in vitro and LADC growth in vivo demonstrating the therapeutic potential of PKCι-ELF3-NOTCH3 signal inhibition to more effectively treat KRAS LADC. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Notch γ-Secretase Inhibitor Dibenzazepine Attenuates Angiotensin II-Induced Abdominal Aortic Aneurysm in ApoE Knockout Mice by Multiple Mechanisms

    PubMed Central

    Zheng, Yue-Hong; Li, Fang-Da; Tian, Cui; Ren, Hua-Liang; Du, Jie; Li, Hui-Hua

    2013-01-01

    Abdominal aortic aneurysm (AAA) is a life-threatening aortic disease in the elderly. Activation of Notch1 pathway plays a critical role in the development of AAA, but the underlying mechanisms remain poorly understood. In the present study, we explored the mechanisms by which Notch1 activation regulates angiotensin II (Ang II)-induced AAA formation and evaluated the therapeutic potential of a new Notch γ-secretase inhibitor, dibenzazepine (DBZ), for the treatment of AAA. Apolipoprotein E knockout (Apo E−/−) mice infused for 4 weeks with Ang II (1000 ng/kg/min, IP) using osmotic mini-pumps were received an intraperitoneal injection of either vehicle or 1 mg/kg/d DBZ. Notch1 signaling was activated in AAA tissue from both Ang II-infused Apo E−/− mice and human undergoing AAA repair in vivo, with increased expression of Notch intracellular domain (NICD) and its target gene Hes1, and this effect was effectively blocked by DBZ. Moreover, infusion of Ang II markedly increased the incidence and severity of AAA in Apo E−/− mice. In contrast, inhibition of Notch activation by DBZ prevented AAA formation in vivo. Furthermore, DBZ markedly prevented Ang II-stimulated accumulation of macrophages and CD4+ T cells, and ERK-mediated angiogenesis, simultaneously reversed Th2 response, in vivo. In conclusion, these findings provide new insight into the multiple mechanisms of Notch signaling involved in AAA formation and suggest that γ-secretase inhibitor DBZ might be a novel therapeutic drug for treating AAAS. PMID:24358274

  15. Inhibition of Delta-induced Notch signaling using fucose analogs

    PubMed Central

    Schneider, Michael; Kumar, Vivek; Nordstrøm, Lars Ulrik; Feng, Lei; Takeuchi, Hideyuki; Hao, Huilin; Luca, Vincent C.; Garcia, K. Christopher; Stanley, Pamela; Wu, Peng; Haltiwanger, Robert S.

    2017-01-01

    Notch is a cell-surface receptor that controls cell fate decisions and is regulated by O-glycans attached to epidermal growth factor-like (EGF) repeats in its extracellular domain. Protein O-fucosyltransferase 1 (Pofut1) modifies EGF repeats with O-fucose and is essential for Notch signaling. Constitutive activation of Notch signaling has been associated with a variety of human malignancies. Therefore, tools for inhibiting Notch activity are being developed as cancer therapeutics. Towards this end, we screened L-fucose analogs for their effects on Notch signaling. Two analogs, 6-alkynyl and 6-alkenyl fucose, were substrates of Pofut1 and were incorporated directly into Notch EGF repeats in cells. Both analogs were potent inhibitors of binding to and activation of Notch1 by Notch ligands Dll1 and Dll4, but not by Jag1. Mutagenesis and modeling studies suggest that incorporation of the analogs into EGF8 of Notch1 markedly reduces the ability of Delta ligands to bind and activate Notch1. PMID:29176671

  16. The complex role of NOTCH receptors and their ligands in the development of hepatoblastoma, cholangiocarcinoma and hepatocellular carcinoma.

    PubMed

    Gil-García, Borja; Baladrón, Victoriano

    2016-02-01

    The NOTCH signalling pathway is one of the key molecular pathways of embryonic development and adult tissues homeostasis in mammals. Mammals have four NOTCH receptors and various ligands that modulate their activity. Many cell disorders, whose genesis involves the NOTCH signalling pathway, have been discovered, including cancer. The mechanisms by which these receptors and their ligands affect liver cell transformation are not yet well understood, and they seem to behave as both oncogenes and tumour-suppressor proteins. In this review, we discuss the published data regarding the role of these proteins in the development of hepatoblastoma, cholangiocarcinoma and hepatocellular carcinoma malignancies. The alteration of the NOTCH signalling pathway may be one of the main drivers of hepatic neoplastic growth. However, this signalling pathway might also modulate the development of specific liver tumour features. The complexity of the function of NOTCH receptors and their ligands may be due to their interactions with many other cell signalling pathways. Furthermore, the different levels of expression and activation of these receptors could be a reason for their distinct and sometimes contradictory effects. © 2015 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.

  17. Notch 1 Receptor, Delta 1 Ligand and HES 1 Transcription Factor are Expressed in the Lining Epithelium of Periapical Cysts (Preliminary Study)

    PubMed Central

    Meliou, E; Kerezoudis, NP; Tosios, KI; Kiaris, H

    2010-01-01

    Periapical cyst is a chronic inflammatory disorder of periradicular tissues. The precise pathological mechanisms involved in periapical cyst enlargement remain unclear. Notch signaling is an evolutionarily conserved pathway with a regulatory role in cell fate decisions during development and in carcinogenesis. To date, there are no published data available on the expression of Notch signaling components in periapical cysts or any other jaw cyst. In this immunohistochemical study we have examined the expression of the receptor Notch 1, the ligand Delta 1 and the transcription factor HES 1 in the epithelium of well defined periapical cysts. Immunostaining reaction of Notch 1, Delta 1 and HES 1 was observed in the cytoplasm and/or the cytoplasmic membrane and occasionally in the nucleus in the majority of epithelial cells of all periapical cysts. The present observations indicate that Notch pathway is active in the epithelium of periapical cysts. It can be speculated that activation of epithelial cells of periapical cysts is associated with activation of Notch pathway and imply involvement of this pathway in periapical cyst growth and expansion. PMID:21116324

  18. Crosstalk between the Notch signaling pathway and non-coding RNAs in gastrointestinal cancers

    PubMed Central

    Pan, Yangyang; Mao, Yuyan; Jin, Rong; Jiang, Lei

    2018-01-01

    The Notch signaling pathway is one of the main signaling pathways that mediates direct contact between cells, and is essential for normal development. It regulates various cellular processes, including cell proliferation, apoptosis, migration, invasion, angiogenesis and metastasis. It additionally serves an important function in tumor progression. Non-coding RNAs mainly include small microRNAs, long non-coding RNAs and circular RNAs. At present, a large body of literature supports the biological significance of non-coding RNAs in tumor progression. It is also becoming increasingly evident that cross-talk exists between Notch signaling and non-coding RNAs. The present review summarizes the current knowledge of Notch-mediated gastrointestinal cancer cell processes, and the effect of the crosstalk between the three major types of non-coding RNAs and the Notch signaling pathway on the fate of gastrointestinal cancer cells. PMID:29285185

  19. Nrf2 regulates cellular behaviors and Notch signaling in oral squamous cell carcinoma cells.

    PubMed

    Fan, Hong; Paiboonrungruan, Chorlada; Zhang, Xinyan; Prigge, Justin R; Schmidt, Edward E; Sun, Zheng; Chen, Xiaoxin

    2017-11-04

    Oxidative stress is known to play a pivotal role in the development of oral squamous cell carcinoma (OSCC). We have demonstrated that activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway has chemopreventive effects against oxidative stress-associated OSCC. However, Nrf2 have dual roles in cancer development; while it prevents carcinogenesis of normal cells, hyperactive Nrf2 also promotes the survival of cancer cells. This study is aimed to understand the function of Nrf2 in regulating cellular behaviors of OSCC cells, and the potential mechanisms through which Nrf2 facilitates OSCC. We established the Nrf2-overexpressing and Nrf2-knockdown OSCC cell lines, and examined the function of Nrf2 in regulating cell proliferation, migration, invasion, cell cycle and colony formation. Our data showed that Nrf2 overexpression promoted cancer phenotypes in OSCC cells, whereas Nrf2 silencing inhibited these phenotypes. In addition, Nrf2 positively regulated Notch signaling pathway in OSCC cells in vitro. Consistent with this observation, Nrf2 activation in Keap1 -/- mice resulted in not only hyperproliferation of squamous epithelial cells in mouse tongue as evidenced by increased expression of PCNA, but also activation of Notch signaling in these cells as evidenced by increased expression of NICD1 and Hes1. In conclusion, Nrf2 regulates cancer behaviors and Notch signaling in OSCC cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Notch3 negatively regulates chemoresistance in breast cancers.

    PubMed

    Gu, Xiaoting; Lu, Chunxiao; He, Dongxu; Lu, Yangfan; Jin, Jian; Liu, Dequan; Ma, Xin

    2016-10-14

    To define the role of the NOTCH signaling pathway in the development of chemoresistance and the associated epithelial-mesenchymal transition (EMT), we investigated the effect of Notch3 on adriamycin (ADM)-resistant human breast cancer cells (MCF-7/ADM cells). We found that Notch3 was downregulated and involved in the chemoresistance of MCF-7/ADM cells, while forced expression of Notch3 reversed the chemoresistance. Furthermore, fos-related antigen 1 (Fra1) was negatively regulated by Notch3 and was highly expressed in MCF-7/ADM cells. Increased Fra1 activated the EMT process. Finally, Notch3 expression was confirmed in clinically chemoresistant samples of breast cancers from patients receiving anthracycline-based chemotherapy. Low expression of Notch3 was an unfavorable predictor of distant relapse-free survival in ER positive breast cancers. Taken together, our findings demonstrate that the Notch3-Fra1 signaling pathway mediates chemoresistance via the EMT.

  1. Complex regulation of HSC emergence by the Notch signaling pathway

    PubMed Central

    Butko, Emerald; Pouget, Claire; Traver, David

    2016-01-01

    Hematopoietic stem cells are formed during embryonic development, and serve as the foundation of the definitive blood program for life. Notch signaling has been well established as an essential direct contributor to HSC specification. However, several recent studies have indicated that the contribution of Notch signaling is complex. HSC specification requires multiple Notch signaling inputs, some received directly by hematopoietic precursors, and others that occur indirectly within neighboring somites. Of note, proinflammatory signals provided by primitive myeloid cells are needed for HSC specification via upregulation of the Notch pathway in hemogenic endothelium. In addition to multiple requirements for Notch activation, recent studies indicate that Notch signaling must subsequently be repressed to permit HSC emergence. Finally, Notch must then be reactivated to maintain HSC fate. In this review, we discuss the growing understanding of the dynamic contributions of Notch signaling to the establishment of hematopoiesis during development. PMID:26586199

  2. Anabolic actions of Notch on mature bone

    PubMed Central

    Liu, Peng; Ping, Yilin; Ma, Meng; Zhang, Demao; Liu, Connie; Zaidi, Samir; Gao, Song; Ji, Yaoting; Lou, Feng; Yu, Fanyuan; Lu, Ping; Stachnik, Agnes; Bai, Mingru; Wei, Chengguo; Zhang, Liaoran; Wang, Ke; Chen, Rong; New, Maria I.; Rowe, David W.; Yuen, Tony; Sun, Li; Zaidi, Mone

    2016-01-01

    Notch controls skeletogenesis, but its role in the remodeling of adult bone remains conflicting. In mature mice, the skeleton can become osteopenic or osteosclerotic depending on the time point at which Notch is activated or inactivated. Using adult EGFP reporter mice, we find that Notch expression is localized to osteocytes embedded within bone matrix. Conditional activation of Notch signaling in osteocytes triggers profound bone formation, mainly due to increased mineralization, which rescues both age-associated and ovariectomy-induced bone loss and promotes bone healing following osteotomy. In parallel, mice rendered haploinsufficient in γ-secretase presenilin-1 (Psen1), which inhibits downstream Notch activation, display almost-absent terminal osteoblast differentiation. Consistent with this finding, pharmacologic or genetic disruption of Notch or its ligand Jagged1 inhibits mineralization. We suggest that stimulation of Notch signaling in osteocytes initiates a profound, therapeutically relevant, anabolic response. PMID:27036007

  3. Epithelial transformation by KLF4 requires Notch1 but not canonical Notch1 signaling

    PubMed Central

    Liu, Zhaoli; Teng, Lihong; Bailey, Sarah K.; Frost, Andra R.; Bland, Kirby I.; LoBuglio, Albert F.; Ruppert, J. Michael; Lobo-Ruppert, Susan M.

    2009-01-01

    The transcription factors Notch1 and KLF4 specify epithelial cell fates and confer stem cell properties. suggesting a functional relationship, each gene can act to promote or suppress tumorigenesis in a context-dependent manner, and alteration of KLF4 or Notch pathway genes in mice gives rise to similar phenotypes. Activation of a conditional allele of KLF4 in RK3E epithelial cells rapidly induces expression of Notch1 mRNA and the active, intracellular form of Notch1. KLF4-induced transformation was suppressed by knockdown of endogenous Notch1 using siRNA or an inhibitor of γ-secretase. Chromatin immunoprecipitation assay shows that KLF4 binds to the proximal Notch1 promoter in human mammary epithelial cells, and siRNA-mediated suppression of KLF4 in human mammary cancer cells results in reduced expression of Notch1. Furthermore, KLF4 and Notch1 expression are correlated in primary human breast tumors (N = 89; pearson analysis, r > 0.5, p < 0.0001). Like KLF4, Notch1 was previously shown to induce transformation of rat cells immortalized with adenovirus E1A, similar to RK3E cells. We therefore compared the signaling requirements for Notch1- or KLF4-induced malignant transformation of RK3E. As expected, transformation by Notch1 was suppressed by dominant-negative CSL or MaML1, inhibitors of canonical Notch1 signaling. However, these inhibitors did not suppress transformation by KLF4. Therefore, while KLF4-induced transformation requires Notch1, canonical Notch1 signaling is not required, and Notch1 may signal through a distinct pathway in cells with increased KLF4 activity. These results suggest that KLF4 could contribute to breast tumor progression by activating synthesis of Notch1 and by promoting signaling through a non-canonical Notch1 pathway. PMID:19717984

  4. [Notch1 signaling participates in the release of inflammatory mediators in mouse RAW264.7 cells via activating NF-κB pathway].

    PubMed

    Zhao, Hongwei; Xu, Che Nan; Huang, Chao; Jiang, Jinzhi; Li, Liangchang

    2017-10-01

    Objective To study the effect of Notch1 signaling on the release of inflammatory mediators in lipopolysaccharide (LPS)-induced macrophages and the related mechanism. Methods The expressions of Notch1 and hairy and enhancer of split 1 (Hes1) mRNAs were investigated by reverse transcription PCR (RT-PCR) in mouse RAW264.7 cells after stimulated with 100 ng/mL LPS for 8 hours. Prior to stimulation with LPS, mouse RAW264.7 cells were treated with DAPT (10 μmol/L), an inhibitor of Notch1 signaling, for 1 hour. The concentrations of tumor necrosis factor (TNF-α), interleukin 1β (IL-1β), IL-6, nitric oxide (NO) and prostaglandin E 2 (PGE 2 ) in cell culture media were measured by ELISA. The mRNA levels of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were examined by RT-PCR. The protein levels of iNOS, COX-2, nuclear factor kappa Bp65 (NF-κBp65) and phosphorylated nuclear factor κB inhibitor α (p-IκBα) were detected by Western blotting. Results The expressions of Notch1 and Hes1 mRNAs significantly increased in mouse RAW264.7 cells after stimulated with LPS. The levels of TNF-α, IL-1β, IL-6, NO and PGE 2 were significantly up-regulated in cell culture media after stimulated with LPS, but the levels of those inflammatory mediators were reduced by DAPT. The mRNA and protein levels of iNOS and COX-2 were significant raised in mouse RAW264.7 cells after stimulated with LPS, while they were inhibited by DAPT. Both IκBα-phosphorylation and NF-κBp65 translocation into nuclear in LPS-induced RAW264.7 cells were also inhibited by DAPT. Conclusion Notch1 signaling activates NF-κB to participate in LPS-induced inflammatory mediator release in macrophages.

  5. Regeneration of Sensory Hair Cells Requires Localized Interactions between the Notch and Wnt Pathways.

    PubMed

    Romero-Carvajal, Andrés; Navajas Acedo, Joaquín; Jiang, Linjia; Kozlovskaja-Gumbrienė, Agnė; Alexander, Richard; Li, Hua; Piotrowski, Tatjana

    2015-08-10

    In vertebrates, mechano-electrical transduction of sound is accomplished by sensory hair cells. Whereas mammalian hair cells are not replaced when lost, in fish they constantly renew and regenerate after injury. In vivo tracking and cell fate analyses of all dividing cells during lateral line hair cell regeneration revealed that support and hair cell progenitors localize to distinct tissue compartments. Importantly, we find that the balance between self-renewal and differentiation in these compartments is controlled by spatially restricted Notch signaling and its inhibition of Wnt-induced proliferation. The ability to simultaneously study and manipulate individual cell behaviors and multiple pathways in vivo transforms the lateral line into a powerful paradigm to mechanistically dissect sensory organ regeneration. The striking similarities to other vertebrate stem cell compartments uniquely place zebrafish to help elucidate why mammals possess such low capacity to regenerate hair cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. A Dual Role for NOTCH Signaling in Joint Cartilage Maintenance and Osteoarthritis

    PubMed Central

    Liu, Zhaoyang; Chen, Jianquan; Mirando, Anthony; Wang, Cuicui; Zuscik, Michael J.; O’Keefe, Regis J.; Hilton, Matthew J.

    2015-01-01

    Loss of NOTCH signaling in postnatal murine joints results in osteoarthritis (OA), indicating a requirement for NOTCH during joint cartilage maintenance. Unexpectedly, NOTCH components are significantly up-regulated in human and murine post-traumatic OA, suggesting either a reparative or pathological role for NOTCH activation in OA. Here we investigated the potential dual role for NOTCH in joint maintenance and OA by generating two mouse models overexpressing the NOTCH1 intracellular domain within postnatal joint cartilage; one with sustained NOTCH activation that likely resembles pathological NOTCH signaling and one with transient NOTCH activation that more closely reflects physiological NOTCH signaling. Sustained NOTCH signaling in joint cartilage leads to an early and progressive OA pathology, while on the contrary, transient NOTCH activation enhances cartilage matrix synthesis and promotes joint maintenance under normal physiological conditions. Using RNA-seq, immunohistochemical, and biochemical approaches we identified several novel targets potentially responsible for NOTCH-mediated cartilage degradation, fibrosis, and OA progression, including components of the IL6/STAT3 and ERK/p38 MAPK pathways; factors that may also contribute to post-traumatic OA development. Collectively, these data demonstrate a dual role for the NOTCH pathway in joint cartilage and identify important downstream NOTCH effectors as potential targets for disease modifying osteoarthritis drugs (DMOADs). PMID:26198357

  7. β-Catenin Up-regulates Atoh1 Expression in Neural Progenitor Cells by Interaction with an Atoh1 3′ Enhancer*

    PubMed Central

    Shi, Fuxin; Cheng, Yen-fu; Wang, Xiaohui L.; Edge, Albert S. B.

    2010-01-01

    Atoh1, a basic helix-loop-helix transcription factor, plays a critical role in the differentiation of several epithelial and neural cell types. We found that β-catenin, the key mediator of the canonical Wnt pathway, increased expression of Atoh1 in mouse neuroblastoma cells and neural progenitor cells, and baseline Atoh1 expression was decreased by siRNA directed at β-catenin. The up-regulation of Atoh1 was caused by an interaction of β-catenin with the Atoh1 enhancer that could be demonstrated by chromatin immunoprecipitation. We found that two putative Tcf-Lef sites in the 3′ enhancer of the Atoh1 gene displayed an affinity for β-catenin and were critical for the activation of Atoh1 transcription because mutation of either site decreased expression of a reporter gene downstream of the enhancer. Tcf-Lef co-activators were found in the complex that bound to these sites in the DNA together with β-catenin. Inhibition of Notch signaling, which has previously been shown to induce bHLH transcription factor expression, increased β-catenin expression in progenitor cells of the nervous system. Because this could be a mechanism for up-regulation of Atoh1 after inhibition of Notch, we tested whether siRNA to β-catenin prevented the increase in Atoh1 and found that β-catenin expression was required for increased expression of Atoh1 after Notch inhibition. PMID:19864427

  8. Quantitative Proteomic Analysis Reveals That Anti-Cancer Effects of Selenium-Binding Protein 1 In Vivo Are Associated with Metabolic Pathways

    PubMed Central

    Ying, Qi; Ansong, Emmanuel; Diamond, Alan M.; Lu, Zhaoxin; Yang, Wancai; Bie, Xiaomei

    2015-01-01

    Previous studies have shown the tumor-suppressive role of selenium-binding protein 1 (SBP1), but the underlying mechanisms are unclear. In this study, we found that induction of SBP1 showed significant inhibition of colorectal cancer cell growth and metastasis in mice. We further employed isobaric tags for relative and absolute quantitation (iTRAQ) to identify proteins that were involved in SBP1-mediated anti-cancer effects in tumor tissues. We identified 132 differentially expressed proteins, among them, 53 proteins were upregulated and 79 proteins were downregulated. Importantly, many of the differentially altered proteins were associated with lipid/glucose metabolism, which were also linked to Glycolysis, MAPK, Wnt, NF-kB, NOTCH and epithelial-mesenchymal transition (EMT) signaling pathways. These results have revealed a novel mechanism that SBP1-mediated cancer inhibition is through altering lipid/glucose metabolic signaling pathways. PMID:25974208

  9. A central role for Notch in effector CD8+ T cell differentiation

    PubMed Central

    Backer, Ronald A.; Helbig, Christina; Gentek, Rebecca; Kent, Andrew; Laidlaw, Brian J.; Dominguez, Claudia X.; de Souza, Yevan S.; van Trierum, Stella E.; van Beek, Ruud; Rimmelzwaan, Guus F.; ten Brinke, Anja; Willemsen, A. Marcel; van Kampen, Antoine H. C.; Kaech, Susan M.; Blander, J. Magarian; van Gisbergen, Klaas; Amsen, Derk

    2014-01-01

    Activated CD8+ T cells choose between terminal effector cell (TEC) or memory precursor cell (MPC) fates. We show that Notch controls this choice. Notch promoted differentiation of immediately protective TECs and was correspondingly required for clearance of an acute influenza virus infection. Notch activated a major portion of the TEC-specific gene expression program and suppressed the MPC-specific program. Expression of Notch receptors was induced on naïve CD8+ T cells by inflammatory mediators and interleukin 2 (IL-2) via mTOR and T-bet dependent pathways. These pathways were subsequently amplified downstream of Notch, creating a positive feedback loop. Notch thus functions as a central hub where information from different sources converges to match effector T cell differentiation to the demands of the infection. PMID:25344724

  10. Wnt activation followed by Notch inhibition promotes mitotic hair cell regeneration in the postnatal mouse cochlea

    PubMed Central

    Li, Wenyan; Chen, Yan; Zhang, Shasha; Tang, Mingliang; Sun, Shan; Chai, Renjie; Li, Huawei

    2016-01-01

    Hair cell (HC) loss is the main cause of permanent hearing loss in mammals. Previous studies have reported that in neonatal mice cochleae, Wnt activation promotes supporting cell (SC) proliferation and Notch inhibition promotes the trans-differentiation of SCs into HCs. However, Wnt activation alone fails to regenerate significant amounts of new HCs, Notch inhibition alone regenerates the HCs at the cost of exhausting the SC population, which leads to the death of the newly regenerated HCs. Mitotic HC regeneration might preserve the SC number while regenerating the HCs, which could be a better approach for long-term HC regeneration. We present a two-step gene manipulation, Wnt activation followed by Notch inhibition, to accomplish mitotic regeneration of HCs while partially preserving the SC number. We show that Wnt activation followed by Notch inhibition strongly promotes the mitotic regeneration of new HCs in both normal and neomycin-damaged cochleae while partially preserving the SC number. Lineage tracing shows that the majority of the mitotically regenerated HCs are derived specifically from the Lgr5+ progenitors with or without HC damage. Our findings suggest that the co-regulation of Wnt and Notch signaling might provide a better approach to mitotically regenerate HCs from Lgr5+ progenitor cells. PMID:27564256

  11. Integrated β-catenin, BMP, PTEN, and Notch signalling patterns the nephron.

    PubMed

    Lindström, Nils O; Lawrence, Melanie L; Burn, Sally F; Johansson, Jeanette A; Bakker, Elvira R M; Ridgway, Rachel A; Chang, C-Hong; Karolak, Michele J; Oxburgh, Leif; Headon, Denis J; Sansom, Owen J; Smits, Ron; Davies, Jamie A; Hohenstein, Peter

    2015-02-03

    The different segments of the nephron and glomerulus in the kidney balance the processes of water homeostasis, solute recovery, blood filtration, and metabolite excretion. When segment function is disrupted, a range of pathological features are presented. Little is known about nephron patterning during embryogenesis. In this study, we demonstrate that the early nephron is patterned by a gradient in β-catenin activity along the axis of the nephron tubule. By modifying β-catenin activity, we force cells within nephrons to differentiate according to the imposed β-catenin activity level, thereby causing spatial shifts in nephron segments. The β-catenin signalling gradient interacts with the BMP pathway which, through PTEN/PI3K/AKT signalling, antagonises β-catenin activity and promotes segment identities associated with low β-catenin activity. β-catenin activity and PI3K signalling also integrate with Notch signalling to control segmentation: modulating β-catenin activity or PI3K rescues segment identities normally lost by inhibition of Notch. Our data therefore identifies a molecular network for nephron patterning.

  12. Notch ligands Delta1 and Jagged1 transmit distinct signals to T-cell precursors

    PubMed Central

    Lehar, Sophie M.; Dooley, James; Farr, Andrew G.; Bevan, Michael J.

    2009-01-01

    Signaling through the Notch pathway plays an essential role in inducing T-lineage commitment and promoting the maturation of immature thymocytes. Using an in vitro culture system, we show that 2 different classes of Notch ligands, Jagged1 or Delta1, transmit distinct signals to T-cell progenitors. OP9 stromal cells expressing either Jagged1 or Delta1 inhibit the differentiation of DN1 thymocytes into the B-cell lineage, but only the Delta1-expressing stromal cells promote the proliferation and maturation of T-cell progenitors through the early double-negative (DN) stages of thymocyte development. Whereas the majority of bone marrow-derived stem cells do not respond to Jagged1 signals, T-cell progenitors respond to Jagged1 signals during a brief window of their development between the DN1 and DN3 stages of thymic development. During these stages, Jagged1 signals can influence the differentiation of immature thymocytes along the natural killer (NK) and γδ T-cell lineages. PMID:15486060

  13. Control of Neural Daughter Cell Proliferation by Multi-level Notch/Su(H)/E(spl)-HLH Signaling

    PubMed Central

    Bivik, Caroline; MacDonald, Ryan B.; Gunnar, Erika; Mazouni, Khalil; Schweisguth, Francois; Thor, Stefan

    2016-01-01

    The Notch pathway controls proliferation during development and in adulthood, and is frequently affected in many disorders. However, the genetic sensitivity and multi-layered transcriptional properties of the Notch pathway has made its molecular decoding challenging. Here, we address the complexity of Notch signaling with respect to proliferation, using the developing Drosophila CNS as model. We find that a Notch/Su(H)/E(spl)-HLH cascade specifically controls daughter, but not progenitor proliferation. Additionally, we find that different E(spl)-HLH genes are required in different neuroblast lineages. The Notch/Su(H)/E(spl)-HLH cascade alters daughter proliferation by regulating four key cell cycle factors: Cyclin E, String/Cdc25, E2f and Dacapo (mammalian p21CIP1/p27KIP1/p57Kip2). ChIP and DamID analysis of Su(H) and E(spl)-HLH indicates direct transcriptional regulation of the cell cycle genes, and of the Notch pathway itself. These results point to a multi-level signaling model and may help shed light on the dichotomous proliferative role of Notch signaling in many other systems. PMID:27070787

  14. Notch Signalling Synchronizes the Zebrafish Segmentation Clock but Is Not Needed To Create Somite Boundaries

    PubMed Central

    Özbudak, Ertuğrul M; Lewis, Julian

    2008-01-01

    Somite segmentation depends on a gene expression oscillator or clock in the posterior presomitic mesoderm (PSM) and on read-out machinery in the anterior PSM to convert the pattern of clock phases into a somite pattern. Notch pathway mutations disrupt somitogenesis, and previous studies have suggested that Notch signalling is required both for the oscillations and for the read-out mechanism. By blocking or overactivating the Notch pathway abruptly at different times, we show that Notch signalling has no essential function in the anterior PSM and is required only in the posterior PSM, where it keeps the oscillations of neighbouring cells synchronized. Using a GFP reporter for the oscillator gene her1, we measure the influence of Notch signalling on her1 expression and show by mathematical modelling that this is sufficient for synchronization. Our model, in which intracellular oscillations are generated by delayed autoinhibition of her1 and her7 and synchronized by Notch signalling, explains the observations fully, showing that there are no grounds to invoke any additional role for the Notch pathway in the patterning of somite boundaries in zebrafish. PMID:18248098

  15. The emerging roles of Notch signaling in leukemia and stem cells

    PubMed Central

    2013-01-01

    The Notch signaling pathway plays a critical role in maintaining the balance between cell proliferation, differentiation and apoptosis, and is a highly conserved signaling pathway that regulates normal development in a context- and dose-dependent manner. Dysregulation of Notch signaling has been suggested to be key events in a variety of hematological malignancies. Notch1 signaling appears to be the central oncogenic trigger in T cell acute lymphoblastic leukemia (T-ALL), in which the majority of human malignancies have acquired mutations that lead to constitutive activation of Notch1 signaling. However, emerging evidence unexpectedly demonstrates that Notch signaling can function as a potent tumor suppressor in other forms of leukemia. This minireview will summarize recent advances related to the roles of activated Notch signaling in human lymphocytic leukemia, myeloid leukemia, stem cells and stromal microenvironment, and we will discuss the perspectives of Notch signaling as a potential therapeutic target as well. PMID:24252593

  16. Thyroid Hormone-Induced Activation of Notch Signaling is Required for Adult Intestinal Stem Cell Development During Xenopus Laevis Metamorphosis.

    PubMed

    Hasebe, Takashi; Fujimoto, Kenta; Kajita, Mitsuko; Fu, Liezhen; Shi, Yun-Bo; Ishizuya-Oka, Atsuko

    2017-04-01

    In Xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (AE) cells appear concomitantly. They proliferate and differentiate to form the adult epithelium (Ep). Thyroid hormone (TH) is well established to trigger this remodeling by regulating the expression of various genes including Notch receptor. To study the role of Notch signaling, we have analyzed the expression of its components, including the ligands (DLL and Jag), receptor (Notch), and targets (Hairy), in the metamorphosing intestine by real-time reverse transcription-polymerase chain reaction and in situ hybridization or immunohistochemistry. We show that they are up-regulated during both natural and TH-induced metamorphosis in a tissue-specific manner. Particularly, Hairy1 is specifically expressed in the AE cells. Moreover, up-regulation of Hairy1 and Hairy2b by TH was prevented by treating tadpoles with a γ-secretase inhibitor (GSI), which inhibits Notch signaling. More importantly, TH-induced up-regulation of LGR5, an adult intestinal stem cell marker, was suppressed by GSI treatment. Our results suggest that Notch signaling plays a role in stem cell development by regulating the expression of Hairy genes during intestinal remodeling. Furthermore, we show with organ culture experiments that prolonged exposure of tadpole intestine to TH plus GSI leads to hyperplasia of secretory cells and reduction of absorptive cells. Our findings here thus provide evidence for evolutionarily conserved role of Notch signaling in intestinal cell fate determination but more importantly reveal, for the first time, an important role of Notch pathway in the formation of adult intestinal stem cells during vertebrate development. Stem Cells 2017;35:1028-1039. © 2016 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  17. Thyroid Hormone‐Induced Activation of Notch Signaling is Required for Adult Intestinal Stem Cell Development During Xenopus Laevis Metamorphosis

    PubMed Central

    Fujimoto, Kenta; Kajita, Mitsuko; Fu, Liezhen; Shi, Yun‐Bo; Ishizuya‐Oka, Atsuko

    2016-01-01

    Abstract In Xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (AE) cells appear concomitantly. They proliferate and differentiate to form the adult epithelium (Ep). Thyroid hormone (TH) is well established to trigger this remodeling by regulating the expression of various genes including Notch receptor. To study the role of Notch signaling, we have analyzed the expression of its components, including the ligands (DLL and Jag), receptor (Notch), and targets (Hairy), in the metamorphosing intestine by real‐time reverse transcription‐polymerase chain reaction and in situ hybridization or immunohistochemistry. We show that they are up‐regulated during both natural and TH‐induced metamorphosis in a tissue‐specific manner. Particularly, Hairy1 is specifically expressed in the AE cells. Moreover, up‐regulation of Hairy1 and Hairy2b by TH was prevented by treating tadpoles with a γ‐secretase inhibitor (GSI), which inhibits Notch signaling. More importantly, TH‐induced up‐regulation of LGR5, an adult intestinal stem cell marker, was suppressed by GSI treatment. Our results suggest that Notch signaling plays a role in stem cell development by regulating the expression of Hairy genes during intestinal remodeling. Furthermore, we show with organ culture experiments that prolonged exposure of tadpole intestine to TH plus GSI leads to hyperplasia of secretory cells and reduction of absorptive cells. Our findings here thus provide evidence for evolutionarily conserved role of Notch signaling in intestinal cell fate determination but more importantly reveal, for the first time, an important role of Notch pathway in the formation of adult intestinal stem cells during vertebrate development. Stem Cells 2017;35:1028–1039 PMID:27870267

  18. Disrupting Jagged1-Notch signaling impairs spatial memory formation in adult mice.

    PubMed

    Sargin, Derya; Botly, Leigh C P; Higgs, Gemma; Marsolais, Alexander; Frankland, Paul W; Egan, Sean E; Josselyn, Sheena A

    2013-07-01

    It is well-known that Notch signaling plays a critical role in brain development and growing evidence implicates this signaling pathway in adult synaptic plasticity and memory formation. The Notch1 receptor is activated by two subclasses of ligands, Delta-like (including Dll1 and Dll4) and Jagged (including Jag1 and Jag2). Ligand-induced Notch1 receptor signaling is modulated by a family of Fringe proteins, including Lunatic fringe (Lfng). Although Dll1, Jag1 and Lfng are critical regulators of Notch signaling, their relative contribution to memory formation in the adult brain is unknown. To investigate the roles of these important components of Notch signaling in memory formation, we examined spatial and fear memory formation in adult mice with reduced expression of Dll1, Jag1, Lfng and Dll1 plus Lfng. We also examined motor activity, anxiety-like behavior and sensorimotor gating using the acoustic startle response in these mice. Of the lines of mutant mice tested, we found that only mice with reduced Jag1 expression (mice heterozygous for a null mutation in Jag1, Jag1(+/-)) showed a selective impairment in spatial memory formation. Importantly, all other behavior including open field activity, conditioned fear memory (both context and discrete cue), acoustic startle response and prepulse inhibition, was normal in this line of mice. These results provide the first in vivo evidence that Jag1-Notch signaling is critical for memory formation in the adult brain. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  19. Self-renewal of CD133(hi) cells by IL6/Notch3 signalling regulates endocrine resistance in metastatic breast cancer.

    PubMed

    Sansone, Pasquale; Ceccarelli, Claudio; Berishaj, Marjan; Chang, Qing; Rajasekhar, Vinagolu K; Perna, Fabiana; Bowman, Robert L; Vidone, Michele; Daly, Laura; Nnoli, Jennifer; Santini, Donatella; Taffurelli, Mario; Shih, Natalie N C; Feldman, Michael; Mao, Jun J; Colameco, Christopher; Chen, Jinbo; DeMichele, Angela; Fabbri, Nicola; Healey, John H; Cricca, Monica; Gasparre, Giuseppe; Lyden, David; Bonafé, Massimiliano; Bromberg, Jacqueline

    2016-02-09

    The mechanisms of metastatic progression from hormonal therapy (HT) are largely unknown in luminal breast cancer. Here we demonstrate the enrichment of CD133(hi)/ER(lo) cancer cells in clinical specimens following neoadjuvant endocrine therapy and in HT refractory metastatic disease. We develop experimental models of metastatic luminal breast cancer and demonstrate that HT can promote the generation of HT-resistant, self-renewing CD133(hi)/ER(lo)/IL6(hi) cancer stem cells (CSCs). HT initially abrogates oxidative phosphorylation (OXPHOS) generating self-renewal-deficient cancer cells, CD133(hi)/ER(lo)/OXPHOS(lo). These cells exit metabolic dormancy via an IL6-driven feed-forward ER(lo)-IL6(hi)-Notch(hi) loop, activating OXPHOS, in the absence of ER activity. The inhibition of IL6R/IL6-Notch pathways switches the self-renewal of CD133(hi) CSCs, from an IL6/Notch-dependent one to an ER-dependent one, through the re-expression of ER. Thus, HT induces an OXPHOS metabolic editing of luminal breast cancers, paradoxically establishing HT-driven self-renewal of dormant CD133(hi)/ER(lo) cells mediating metastatic progression, which is sensitive to dual targeted therapy.

  20. miR-598 inhibits metastasis in colorectal cancer by suppressing JAG1/Notch2 pathway stimulating EMT.

    PubMed

    Chen, Jia; Zhang, Haichen; Chen, Ying; Qiao, Guanglei; Jiang, Weihua; Ni, Peihua; Liu, Xiangfan; Ma, Lijun

    2017-03-01

    MicroRNAs (miRNAs) are a class of endogenous, evolutionarily conserved small non-coding RNA molecules that mediate the posttranscriptional process of target gene, leading to translational repression or degradation of target mRNAs. A series of studies have indicated that miRNAs play an important role in tumor initiation, development and progression. In this study, we found that down regulation of miR-598 was a frequent event in CRC tissues compared to the paracarcinoma tissues. And the study demonstrated that miR-598 was implicated in CRC metastasis. Transwell migration assay revealed that elevated miR-598 expression reduces CRC cell migration. Moreover, our study showed that suppression of miR-598 expression induces CRC cell epithelialmesenchymal transition(EMT) and overexpression of miR-598 inhibits CRC cell EMT. In addition, bioinformatics target prediction identified JAG1 as a putative target of miR-598. Knockdown of miR-598 was shown to upregulate JAG1 expression. Furthermore, overexpression of miR-598 suppressed the expression of JAG1. Consistent results were also obtained when the regulation of JAG1 expression by miR-598 was further specified in CRC tissues. Moreover, overexpression of JAG1 induces epithelialmesenchymal transition(EMT) and promotes the metastasis of CRC cells. Decreased Notch2 expression suppresses CRC cells metastasis and EMT. Together, these results indicate that miR-598 is a novel regulator of colorectal cancer metastasis. Our data suggest miR-598 is implicated in regulating Epithelial-mesenchymal transitions by directly suppressing its downstream target gene JAG1 to inactivate Notch signaling pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Planar cell polarity controls directional Notch signaling in the Drosophila leg

    PubMed Central

    Capilla, Amalia; Johnson, Ruth; Daniels, Maki; Benavente, María; Bray, Sarah J.; Galindo, Máximo Ibo

    2012-01-01

    The generation of functional structures during development requires tight spatial regulation of signaling pathways. Thus, in Drosophila legs, in which Notch pathway activity is required to specify joints, only cells distal to ligand-producing cells are capable of responding. Here, we show that the asymmetric distribution of planar cell polarity (PCP) proteins correlates with this spatial restriction of Notch activation. Frizzled and Dishevelled are enriched at distal sides of each cell and hence localize at the interface with ligand-expressing cells in the non-responding cells. Elimination of PCP gene function in cells proximal to ligand-expressing cells is sufficient to alleviate the repression, resulting in ectopic Notch activity and ectopic joint formation. Mutations that compromise a direct interaction between Dishevelled and Notch reduce the efficacy of repression. Likewise, increased Rab5 levels or dominant-negative Deltex can suppress the ectopic joints. Together, these results suggest that PCP coordinates the spatial activity of the Notch pathway by regulating endocytic trafficking of the receptor. PMID:22736244

  2. Expression of Jagged1/Notch3 Signaling Pathway and their Relationship with the Tumor Angiogenesis in TNBC.

    PubMed

    Xue, Siliang; He, Lang; Zhang, Xiao; Zhou, Jin; Li, Fanghua; Wang, Xiaoshan

    2017-02-01

    Jagged1/Notch3 signaling pathway plays a key role in angiogenesis of breast cancer, but little is known in TNBC. This study was designed to investigate the expression of Jagged1/Notch3 mRNA and protein in TNBC, analyze their correlations with clinicopathological characteristics and prognosis. Moreover, the interrelationship among Jagged1/Notch3 and VEGF was initially evaluated. Jagged1/Notch3 mRNA and protein expression levels were determined by Q-RT-PCR and Western blotting. Additionally, Immunohistochemistry for Jagged1/Notch3 was detected by Ventana platform, VEGF and CD34 was performed using the EnVision/HRP technique. mRNA transcriptionof Jagged1/Notch3 was in accord with protein expression. TNBC patients with positive Jagged1 expression had poorer DFS (p = 0.008) and OS (p = 0.004). Jagged1 expression was independent predictors of OS (p = 0.038). The expression of VEGF was positively correlative to MVD (p = 0.018), MVD was significantly associated with Jagged1 (p <0.0001) and Notch3 (p <0.0001). The expression of Jagged1/Notch3 has no correlation with VEGF, only in positive VEGF expression of TNBC patients Jagged1/Notch3 had influence on DFS and OS (p <0.05). Jagged1/Notch3 was -expressed at both the mRNA and protein levels, Jagged1 served as an independent predictor of poor prognosis. We speculate that there is a cross-talk between Jagged1/Notch3 and VEGF in TNBC angiogenesis. Jagged1/Notch3 is expected to be an important signaling pathway for TNBC progression and a potential target for TNBC neovascularization therapy. Copyright © 2017 IMSS. Published by Elsevier Inc. All rights reserved.

  3. [Expression of Notch Gene and Its Role of Anti-apoptosis and Drug-resistance of Cells in Chronic Lymphocytic Leukemia].

    PubMed

    Zhang, Jin-Yan; Zhang, Ju-Shun; Xu, Zhen-Shu

    2015-08-01

    To investigate the expression of Notch gene in chronic lymphocytic leukemia cells and to explore the change of Notch protein after the therapy with cytosine arabinoside or dexmethasone, and the mechanism of Notch mediated anti-apoptosis and drug-resistance in chronic lymphocytic leukemia cells. The mononuclear cells from bone marrow or peripheral blood of chronic lymphocytic leukemia patients (24 cases) and healthy donors (14 cases) were collected, then the expression of Notch gene, BCL-2, as well as NF-κB gene were detected by real-time fluorescent quantitative PCR (qRT-PCR) at the level of transcription. The change of Notch protein in L1210 cell lines after therapy with cytosine arabinoside and dexmethasone was determined by Western blot. mRNA expression levels of Notch1, Notch2, BCL-2 and NF-κB gene in CLL group were significantly higher than those in healthy control group (0.8556 ± 0.8726 vs 0.6731 ± 0.5334, P = 0.0182; 1.2273 ± 0.8207 vs 0.6577 ± 0.6424, P < 0.0001; 8.0960 ± 7.5661 vs 0.5969 ± 0.4976, P < 0.0001; 1.0966 ± 0.6925 vs 0.5373 ± 0.7180, P < 0.0001, respectively), but no significant difference was found between Notch3 and Notch4 gene (1.1914 ± 2.4219 vs 0.8713 ± 0.7937, P = 0.3427; 0.8174 ± 1.0869 vs 0.9752 ± 1.3446, P = 0.2402, respectively). Notch1 protein expression in L1210 cells were significantly decreased after treating with cytosine arabinoside of low and middle concentrations, but increased after treating with cytosine arabinoside of high concentration or prolonging time of cytosine arabinoside of middle con-centration. Notch1 protein expression in L1210 cells dereased after treating with dexamethasone, but did not be changed with the different concentrations and different times of dexmethason. The transcription level of Notch gene in CLL patients significantly higher than that in normal controls. The Notch1 protein expression is down-regulated in process of inhibiting L1210 cell proliferation by Ara-C and dexmethason. Notch signaling pathway may mediated anti-apoptosis and drug resistance of CLL cells. Notch molecule possibly plays an important role in the anti-apoptosis and drug-resistance of CLL cells.

  4. Music-induced cortical plasticity and lateral inhibition in the human auditory cortex as foundations for tonal tinnitus treatment.

    PubMed

    Pantev, Christo; Okamoto, Hidehiko; Teismann, Henning

    2012-01-01

    Over the past 15 years, we have studied plasticity in the human auditory cortex by means of magnetoencephalography (MEG). Two main topics nurtured our curiosity: the effects of musical training on plasticity in the auditory system, and the effects of lateral inhibition. One of our plasticity studies found that listening to notched music for 3 h inhibited the neuronal activity in the auditory cortex that corresponded to the center-frequency of the notch, suggesting suppression of neural activity by lateral inhibition. Subsequent research on this topic found that suppression was notably dependent upon the notch width employed, that the lower notch-edge induced stronger attenuation of neural activity than the higher notch-edge, and that auditory focused attention strengthened the inhibitory networks. Crucially, the overall effects of lateral inhibition on human auditory cortical activity were stronger than the habituation effects. Based on these results we developed a novel treatment strategy for tonal tinnitus-tailor-made notched music training (TMNMT). By notching the music energy spectrum around the individual tinnitus frequency, we intended to attract lateral inhibition to auditory neurons involved in tinnitus perception. So far, the training strategy has been evaluated in two studies. The results of the initial long-term controlled study (12 months) supported the validity of the treatment concept: subjective tinnitus loudness and annoyance were significantly reduced after TMNMT but not when notching spared the tinnitus frequencies. Correspondingly, tinnitus-related auditory evoked fields (AEFs) were significantly reduced after training. The subsequent short-term (5 days) training study indicated that training was more effective in the case of tinnitus frequencies ≤ 8 kHz compared to tinnitus frequencies >8 kHz, and that training should be employed over a long-term in order to induce more persistent effects. Further development and evaluation of TMNMT therapy are planned. A goal is to transfer this novel, completely non-invasive and low-cost treatment approach for tonal tinnitus into routine clinical practice.

  5. Music-induced cortical plasticity and lateral inhibition in the human auditory cortex as foundations for tonal tinnitus treatment

    PubMed Central

    Pantev, Christo; Okamoto, Hidehiko; Teismann, Henning

    2012-01-01

    Over the past 15 years, we have studied plasticity in the human auditory cortex by means of magnetoencephalography (MEG). Two main topics nurtured our curiosity: the effects of musical training on plasticity in the auditory system, and the effects of lateral inhibition. One of our plasticity studies found that listening to notched music for 3 h inhibited the neuronal activity in the auditory cortex that corresponded to the center-frequency of the notch, suggesting suppression of neural activity by lateral inhibition. Subsequent research on this topic found that suppression was notably dependent upon the notch width employed, that the lower notch-edge induced stronger attenuation of neural activity than the higher notch-edge, and that auditory focused attention strengthened the inhibitory networks. Crucially, the overall effects of lateral inhibition on human auditory cortical activity were stronger than the habituation effects. Based on these results we developed a novel treatment strategy for tonal tinnitus—tailor-made notched music training (TMNMT). By notching the music energy spectrum around the individual tinnitus frequency, we intended to attract lateral inhibition to auditory neurons involved in tinnitus perception. So far, the training strategy has been evaluated in two studies. The results of the initial long-term controlled study (12 months) supported the validity of the treatment concept: subjective tinnitus loudness and annoyance were significantly reduced after TMNMT but not when notching spared the tinnitus frequencies. Correspondingly, tinnitus-related auditory evoked fields (AEFs) were significantly reduced after training. The subsequent short-term (5 days) training study indicated that training was more effective in the case of tinnitus frequencies ≤ 8 kHz compared to tinnitus frequencies >8 kHz, and that training should be employed over a long-term in order to induce more persistent effects. Further development and evaluation of TMNMT therapy are planned. A goal is to transfer this novel, completely non-invasive and low-cost treatment approach for tonal tinnitus into routine clinical practice. PMID:22754508

  6. Indole-3-Carbinol Promotes Goblet-Cell Differentiation Regulating Wnt and Notch Signaling Pathways AhR-Dependently.

    PubMed

    Park, Joo-Hung; Lee, Jeong-Min; Lee, Eun-Jin; Hwang, Won-Bhin; Kim, Da-Jeong

    2018-04-30

    Using an in vitro model of intestinal organoids derived from intestinal crypts, we examined effects of indole-3-carbinol (I3C), a phytochemical that has anticancer and aryl hydrocarbon receptor (AhR)-activating abilities and thus is sold as a dietary supplement, on the development of intestinal organoids and investigated the underlying mechanisms. I3C inhibited the in vitro development of mouse intestinal organoids. Addition of α-naphthoflavone, an AhR antagonist or AhR siRNA transfection, suppressed I3C function, suggesting that I3C-mediated interference with organoid development is AhR-dependent. I3C increased the expression of Muc2 and lysozyme, lineage-specific genes for goblet cells and Paneth cells, respectively, but inhibits the expression of IAP, a marker gene for enterocytes. In the intestines of mice treated with I3C, the number of goblet cells was reduced, but the number of Paneth cells and the depth and length of crypts and villi were not changed. I3C increased the level of active nonphosphorylated β-catenin, but suppressed the Notch signal. As a result, expression of Hes1, a Notch target gene and a transcriptional repressor that plays a key role in enterocyte differentiation, was reduced, whereas expression of Math1, involved in the differentiation of secretory lineages, was increased. These results provide direct evidence for the role of AhR in the regulation of the development of intestinal stem cells and indicate that such regulation is likely mediated by regulation of Wnt and Notch signals.

  7. Tissue factor pathway inhibitor-2: a novel gene involved in zebrafish central nervous system development.

    PubMed

    Zhang, Yanli; Wang, Lina; Zhou, Wenhao; Wang, Huijun; Zhang, Jin; Deng, Shanshan; Li, Weihua; Li, Huawei; Mao, Zuohua; Ma, Duan

    2013-09-01

    Tissue factor pathway inhibitor-2 (Tfpi-2) is an important serine protease inhibitor in the extracellular matrix (ECM), but its precise physiological significance remains unknown. This work is part of a series of studies intended to investigate functional roles of Tfpi-2 and explore the underlying molecular mechanisms. First, we cloned and identified zebrafish Tfpi-2 (zTfpi-2) as an evolutionarily conserved protein essential for zebrafish development. We also demonstrated that ztfpi-2 is mainly expressed in the central nervous system (CNS) of zebrafish, and embryonic depletion of ztfpi-2 caused severe CNS defects. In addition, changes of neural markers, including pax2a, egr2b, huC, ngn1, gfap and olig2, confirmed the presence of developmental abnormalities in the relevant regions of ztfpi-2 morphants. Using microarray analysis, we found that members of the Notch pathway, especially her4 and mib, which mediate lateral inhibition in CNS development, were also downregulated. Intriguingly, both her4 and mib were able to partially rescue the ztfpi-2 morphant phenotype. Furthermore, Morpholino knockdown of ztfpi-2 resulted in upregulation of neuronal markers while downregulation of glial markers, providing evidence that the Notch pathway is probably involved in ztfpi-2-mediated CNS development. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Role of JAK/STAT signaling in neuroepithelial stem cell maintenance and proliferation in the Drosophila optic lobe

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Wei; Li, Yonggang; Zhou, Liya

    2011-07-15

    Highlights: {yields} JAK/STAT activity is graded in the Drosophila optic lobe neuroepithelium. {yields} Inactivation of JAK signaling causes disintegration of the optic lobe neuroepithelium and depletion of the neuroepithelial stem cells. {yields} JAK pathway overactivation promotes neuroepithelial overgrowth. {yields} Notch signaling acts downstream of JAK/STAT to promote neuroepithelial growth and expansion. -- Abstract: During Drosophila optic lobe development, proliferation and differentiation must be tightly modulated to reach its normal size for proper functioning. The JAK/STAT pathway plays pleiotropic roles in Drosophila development and in the larval brain, has been shown to inhibit medulla neuroblast formation. In this study, we findmore » that JAK/STAT activity is required for the maintenance and proliferation of the neuroepithelial stem cells in the optic lobe. In loss-of-function JAK/STAT mutant brains, the neuroepithelial cells lose epithelial cell characters and differentiate prematurely while ectopic activation of this pathway is sufficient to induce neuroepithelial overgrowth in the optic lobe. We further show that Notch signaling acts downstream of JAK/STAT to control the maintenance and growth of the optic lobe neuroepithelium. Thus, in addition to its role in suppression of neuroblast formation, the JAK/STAT pathway is necessary and sufficient for optic lobe neuroepithelial growth.« less

  9. Curcumin Inhibits Chondrocyte Hypertrophy of Mesenchymal Stem Cells through IHH and Notch Signaling Pathways.

    PubMed

    Cao, Zhen; Dou, Ce; Dong, Shiwu

    2017-01-01

    Using tissue engineering technique to repair cartilage damage caused by osteoarthritis is a promising strategy. However, the regenerated tissue usually is fibrous cartilage, which has poor mechanical characteristics compared to hyaline cartilage. Chondrocyte hypertrophy plays an important role in this process. Thus, it is very important to find out a suitable way to maintain the phenotype of chondrocytes and inhibit chondrocyte hypertrophy. Curcumin deriving from turmeric was reported with anti-inflammatory and anti-tumor pharmacological effects. However, the role of curcumin in metabolism of chondrocytes, especially in the chondrocyte hypertrophy remains unclear. Mesenchymal stem cells (MSCs) are widely used in cartilage tissue engineering as seed cells. So we investigated the effect of curcumin on chondrogenesis and chondrocyte hypertrophy in MSCs through examination of cell viability, glycosaminoglycan synthesis and specific gene expression. We found curcumin had no effect on expression of chondrogenic markers including Sox9 and Col2a1 while hypertrophic markers including Runx2 and Col10a1 were down-regulated. Further exploration showed that curcumin inhibited chondrocyte hypertrophy through Indian hedgehog homolog (IHH) and Notch signalings. Our results indicated curcumin was a potential agent in modulating cartilage homeostasis and maintaining chondrocyte phenotype.

  10. Genomics and expression profiles of the Hedgehog and Notch signaling pathways in sea urchin development.

    PubMed

    Walton, Katherine D; Croce, Jenifer C; Glenn, Thomas D; Wu, Shu-Yu; McClay, David R

    2006-12-01

    The Hedgehog (Hh) and Notch signal transduction pathways control a variety of developmental processes including cell fate choice, differentiation, proliferation, patterning and boundary formation. Because many components of these pathways are conserved, it was predicted and confirmed that pathway components are largely intact in the sea urchin genome. Spatial and temporal location of these pathways in the embryo, and their function in development offer added insight into their mechanistic contributions. Accordingly, all major components of both pathways were identified and annotated in the sea urchin Strongylocentrotus purpuratus genome and the embryonic expression of key components was explored. Relationships of the pathway components, and modifiers predicted from the annotation of S. purpuratus, were compared against cnidarians, arthropods, urochordates, and vertebrates. These analyses support the prediction that the pathways are highly conserved through metazoan evolution. Further, the location of these two pathways appears to be conserved among deuterostomes, and in the case of Notch at least, display similar capacities in endomesoderm gene regulatory networks. RNA expression profiles by quantitative PCR and RNA in situ hybridization reveal that Hedgehog is produced by the endoderm beginning just prior to invagination, and signals to the secondary mesenchyme-derived tissues at least until the pluteus larva stage. RNA in situ hybridization of Notch pathway members confirms that Notch functions sequentially in the vegetal-most secondary mesenchyme cells and later in the endoderm. Functional analyses in future studies will embed these pathways into the growing knowledge of gene regulatory networks that govern early specification and morphogenesis.

  11. Production of proinflammatory mediators in activated microglia is synergistically regulated by Notch-1, glycogen synthase kinase (GSK-3β) and NF-κB/p65 signalling.

    PubMed

    Cao, Qiong; Karthikeyan, Aparna; Dheen, S Thameem; Kaur, Charanjit; Ling, Eng-Ang

    2017-01-01

    Microglia activation and associated inflammatory response are involved in the pathogenesis of different neurodegenerative diseases. We have reported that Notch-1 and NF-κB/p65 signalling pathways operate in synergy in regulating the production of proinflammatory mediators in activated microglia. In the latter, there is also evidence by others that glycogen synthase kinase 3β (GSK-3β) mediates the release of proinflammatory cytokines but the interrelationships between the three signalling pathways have not been fully clarified. This is an important issue as activated microglia are potential therapeutic target for amelioration of microglia mediated neuroinflammation. Here we show that blocking of Notch-1 with N-[(3,5-Difluorophenyl) acetyl]-L-alanyl-2-phenylglycine-1,1-dimethylethyl ester (DAPT) in LPS activated BV-2 microglia not only suppressed Notch intracellular domain (NICD) and Hes-1 protein expression, but also that of GSK-3β. Conversely, blocking of the latter with lithium chloride (LiCl) decreased NICD expression in a dose-dependent manner; moreover, Hes-1 immunofluorescence was attenuated. Along with this, the protein expression level of p-GSK-3β and p-AKT protein expression was significantly increased. Furthermore, DAPT and LiCl decreased production of IL-1β, TNF-α, IL-6, iNOS, Cox2 and MCP-1; however, IL-10 expression was increased notably in LiCl treated cells. The effects of DAPT and LiCl on changes of the above-mentioned biomarkers were confirmed by immunofluorescence in both BV-2 and primary microglia. Additionally, NF-κB/p65 immunofluorescence was attenuated by DAPT and LiCl; as opposed to this, IκBα protein expression was increased. Taken together, it is suggested that Notch-1, NF-κB/p65 and GSK-3β operate in synergy to inhibit microglia activation. This may be effected via increased expression of phospho-GSK-3β (p-GSK-3β), phospho-protein kinase B (PKB) (p-AKT) and IκBα. It is concluded that the three signalling pathways are functionally interlinked in regulating microglia activation.

  12. Downregulation of RND3/RhoE in glioblastoma patients promotes tumorigenesis through augmentation of notch transcriptional complex activity.

    PubMed

    Liu, Baohui; Lin, Xi; Yang, Xiangsheng; Dong, Huimin; Yue, Xiaojing; Andrade, Kelsey C; Guo, Zhentao; Yang, Jian; Wu, Liquan; Zhu, Xiaonan; Zhang, Shenqi; Tian, Daofeng; Wang, Junmin; Cai, Qiang; Chen, Qizuan; Mao, Shanping; Chen, Qianxue; Chang, Jiang

    2015-09-01

    Activation of Notch signaling contributes to glioblastoma multiform (GBM) tumorigenesis. However, the molecular mechanism that promotes the Notch signaling augmentation during GBM genesis remains largely unknown. Identification of new factors that regulate Notch signaling is critical for tumor treatment. The expression levels of RND3 and its clinical implication were analyzed in GBM patients. Identification of RND3 as a novel factor in GBM genesis was demonstrated in vitro by cell experiments and in vivo by a GBM xenograft model. We found that RND3 expression was significantly decreased in human glioblastoma. The levels of RND3 expression were inversely correlated with Notch activity, tumor size, and tumor cell proliferation, and positively correlated with patient survival time. We demonstrated that RND3 functioned as an endogenous repressor of the Notch transcriptional complex. RND3 physically interacted with NICD, CSL, and MAML1, the Notch transcriptional complex factors, promoted NICD ubiquitination, and facilitated the degradation of these cofactor proteins. We further revealed that RND3 facilitated the binding of NICD to FBW7, a ubiquitin ligase, and consequently enhanced NICD protein degradation. Therefore, Notch transcriptional activity was inhibited. Forced expression of RND3 repressed Notch signaling, which led to the inhibition of glioblastoma cell proliferation in vitro and tumor growth in the xenograft mice in vivo. Downregulation of RND3, however, enhanced Notch signaling activity, and subsequently promoted glioma cell proliferation. Inhibition of Notch activity abolished RND3 deficiency-mediated GBM cell proliferation. We conclude that downregulation of RND3 is responsible for the enhancement of Notch activity that promotes glioblastoma genesis. © 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  13. Downregulation of RND3/RhoE in glioblastoma patients promotes tumorigenesis through augmentation of notch transcriptional complex activity

    PubMed Central

    Liu, Baohui; Lin, Xi; Yang, Xiangsheng; Dong, Huimin; Yue, Xiaojing; Andrade, Kelsey C; Guo, Zhentao; Yang, Jian; Wu, Liquan; Zhu, Xiaonan; Zhang, Shenqi; Tian, Daofeng; Wang, Junmin; Cai, Qiang; Chen, Qizuan; Mao, Shanping; Chen, Qianxue; Chang, Jiang

    2015-01-01

    Activation of Notch signaling contributes to glioblastoma multiform (GBM) tumorigenesis. However, the molecular mechanism that promotes the Notch signaling augmentation during GBM genesis remains largely unknown. Identification of new factors that regulate Notch signaling is critical for tumor treatment. The expression levels of RND3 and its clinical implication were analyzed in GBM patients. Identification of RND3 as a novel factor in GBM genesis was demonstrated in vitro by cell experiments and in vivo by a GBM xenograft model. We found that RND3 expression was significantly decreased in human glioblastoma. The levels of RND3 expression were inversely correlated with Notch activity, tumor size, and tumor cell proliferation, and positively correlated with patient survival time. We demonstrated that RND3 functioned as an endogenous repressor of the Notch transcriptional complex. RND3 physically interacted with NICD, CSL, and MAML1, the Notch transcriptional complex factors, promoted NICD ubiquitination, and facilitated the degradation of these cofactor proteins. We further revealed that RND3 facilitated the binding of NICD to FBW7, a ubiquitin ligase, and consequently enhanced NICD protein degradation. Therefore, Notch transcriptional activity was inhibited. Forced expression of RND3 repressed Notch signaling, which led to the inhibition of glioblastoma cell proliferation in vitro and tumor growth in the xenograft mice in vivo. Downregulation of RND3, however, enhanced Notch signaling activity, and subsequently promoted glioma cell proliferation. Inhibition of Notch activity abolished RND3 deficiency-mediated GBM cell proliferation. We conclude that downregulation of RND3 is responsible for the enhancement of Notch activity that promotes glioblastoma genesis. PMID:26108681

  14. Competition between Jagged-Notch and Endothelin1 Signaling Selectively Restricts Cartilage Formation in the Zebrafish Upper Face

    PubMed Central

    Barske, Lindsey; Askary, Amjad; Zuniga, Elizabeth; Balczerski, Bartosz; Bump, Paul; Nichols, James T.; Crump, J. Gage

    2016-01-01

    The intricate shaping of the facial skeleton is essential for function of the vertebrate jaw and middle ear. While much has been learned about the signaling pathways and transcription factors that control facial patterning, the downstream cellular mechanisms dictating skeletal shapes have remained unclear. Here we present genetic evidence in zebrafish that three major signaling pathways − Jagged-Notch, Endothelin1 (Edn1), and Bmp − regulate the pattern of facial cartilage and bone formation by controlling the timing of cartilage differentiation along the dorsoventral axis of the pharyngeal arches. A genomic analysis of purified facial skeletal precursors in mutant and overexpression embryos revealed a core set of differentiation genes that were commonly repressed by Jagged-Notch and induced by Edn1. Further analysis of the pre-cartilage condensation gene barx1, as well as in vivo imaging of cartilage differentiation, revealed that cartilage forms first in regions of high Edn1 and low Jagged-Notch activity. Consistent with a role of Jagged-Notch signaling in restricting cartilage differentiation, loss of Notch pathway components resulted in expanded barx1 expression in the dorsal arches, with mutation of barx1 rescuing some aspects of dorsal skeletal patterning in jag1b mutants. We also identified prrx1a and prrx1b as negative Edn1 and positive Bmp targets that function in parallel to Jagged-Notch signaling to restrict the formation of dorsal barx1+ pre-cartilage condensations. Simultaneous loss of jag1b and prrx1a/b better rescued lower facial defects of edn1 mutants than loss of either pathway alone, showing that combined overactivation of Jagged-Notch and Bmp/Prrx1 pathways contribute to the absence of cartilage differentiation in the edn1 mutant lower face. These findings support a model in which Notch-mediated restriction of cartilage differentiation, particularly in the second pharyngeal arch, helps to establish a distinct skeletal pattern in the upper face. PMID:27058748

  15. Notch signaling is significantly suppressed in basal cell carcinomas and activation induces basal cell carcinoma cell apoptosis.

    PubMed

    Shi, Feng-Tao; Yu, Mei; Zloty, David; Bell, Robert H; Wang, Eddy; Akhoundsadegh, Noushin; Leung, Gigi; Haegert, Anne; Carr, Nicholas; Shapiro, Jerry; McElwee, Kevin J

    2017-04-01

    A subset of basal cell carcinomas (BCCs) are directly derived from hair follicles (HFs). In some respects, HFs can be defined as 'ordered' skin appendage growths, while BCCs can be regarded as 'disordered' skin appendage growths. The aim of the present study was to examine HFs and BCCs to define the expression of common and unique signaling pathways in each skin appendage. Human nodular BCCs, along with HFs and non‑follicular skin epithelium from normal individuals, were examined using microarrays, qPCR, and immunohistochemistry. Subsequently, BCC cells and root sheath keratinocyte cells from HFs were cultured and treated with Notch signaling peptide Jagged1 (JAG1). Gene expression, protein levels, and cell apoptosis susceptibility were assessed using qPCR, immunoblotting, and flow cytometry, respectively. Specific molecular mechanisms were found to be involved in the process of cell self‑renewal in the HFs and BCCs, including Notch and Hedgehog signaling pathways. However, several key Notch signaling factors showed significant differential expression in BCCs compared with HFs. Stimulating Notch signaling with JAG1 induced apoptosis of BCC cells by increasing Fas ligand expression and downstream caspase-8 activation. The present study showed that Notch signaling pathway activity is suppressed in BCCs, and is highly expressed in HFs. Elements of the Notch pathway could, therefore, represent targets for the treatment of BCCs and potentially in hair follicle engineering.

  16. Hippo signaling is required for Notch-dependent smooth muscle differentiation of neural crest.

    PubMed

    Manderfield, Lauren J; Aghajanian, Haig; Engleka, Kurt A; Lim, Lillian Y; Liu, Feiyan; Jain, Rajan; Li, Li; Olson, Eric N; Epstein, Jonathan A

    2015-09-01

    Notch signaling has well-defined roles in the assembly of arterial walls and in the development of the endothelium and smooth muscle of the vasculature. Hippo signaling regulates cellular growth in many tissues, and contributes to regulation of organ size, in addition to other functions. Here, we show that the Notch and Hippo pathways converge to regulate smooth muscle differentiation of the neural crest, which is crucial for normal development of the aortic arch arteries and cranial vasculature during embryonic development. Neural crest-specific deletion of the Hippo effectors Yap and Taz produces neural crest precursors that migrate normally, but fail to produce vascular smooth muscle, and Notch target genes such as Jagged1 fail to activate normally. We show that Yap is normally recruited to a tissue-specific Jagged1 enhancer by directly interacting with the Notch intracellular domain (NICD). The Yap-NICD complex is recruited to chromatin by the DNA-binding protein Rbp-J in a Tead-independent fashion. Thus, Hippo signaling can modulate Notch signaling outputs, and components of the Hippo and Notch pathways physically interact. Convergence of Hippo and Notch pathways by the mechanisms described here might be relevant for the function of these signaling cascades in many tissues and in diseases such as cancer. © 2015. Published by The Company of Biologists Ltd.

  17. Notch Signaling Pathway Is Activated in Motoneurons of Spinal Muscular Atrophy

    PubMed Central

    Caraballo-Miralles, Víctor; Cardona-Rossinyol, Andrea; Garcera, Ana; Torres-Benito, Laura; Soler, Rosa M.; Tabares, Lucía; Lladó, Jerònia; Olmos, Gabriel

    2013-01-01

    Spinal muscular atrophy (SMA) is a neurodegenerative disease produced by low levels of Survival Motor Neuron (SMN) protein that affects alpha motoneurons in the spinal cord. Notch signaling is a cell-cell communication system well known as a master regulator of neural development, but also with important roles in the adult central nervous system. Aberrant Notch function is associated with several developmental neurological disorders; however, the potential implication of the Notch pathway in SMA pathogenesis has not been studied yet. We report here that SMN deficiency, induced in the astroglioma cell line U87MG after lentiviral transduction with a shSMN construct, was associated with an increase in the expression of the main components of Notch signaling pathway, namely its ligands, Jagged1 and Delta1, the Notch receptor and its active intracellular form (NICD). In the SMNΔ7 mouse model of SMA we also found increased astrocyte processes positive for Jagged1 and Delta1 in intimate contact with lumbar spinal cord motoneurons. In these motoneurons an increased Notch signaling was found, as denoted by increased NICD levels and reduced expression of the proneural gene neurogenin 3, whose transcription is negatively regulated by Notch. Together, these findings may be relevant to understand some pathologic attributes of SMA motoneurons. PMID:23759991

  18. Role of CSL-dependent and independent Notch signaling pathways in cell apoptosis.

    PubMed

    Zeng, Chong; Xing, Rui; Liu, Jing; Xing, Feiyue

    2016-01-01

    Apoptosis is a normally biological phenomenon in various organisms, involving complexly molecular mechanisms with a series of signaling processes. Notch signaling is found evolutionarily conserved in many species, playing a critical role in embryonic development, normal tissue homeostasis, angiogenesis and immunoregulation. The focus of this review is on currently novel advances about roles of CSL-dependent and independent Notch signaling pathways in cell apoptosis. The CSL can bind Notch intracellular domain (NIC) to act as a switch in mediating transcriptional activation or inactivation of the Notch signaling pathway downstream genes in the nucleus. It shows that CSL-dependent signaling regulates the cell apoptosis through Hes-1-PTEN-AKT-mTOR signaling, but rather the CSL-independent signaling mediates the cell apoptosis possibly via NIC-mTORC2-AKT-mTOR signaling, providing a new insight into apoptotic mechanisms.

  19. Inhibition of cell growth and induction of apoptosis in ovarian carcinoma cell lines CaOV3 and SKOV3 by natural withanolide Withaferin A.

    PubMed

    Zhang, Xuan; Samadi, Abbas K; Roby, Katherine F; Timmermann, Barbara; Cohen, Mark S

    2012-03-01

    Withaferin A, a natural withanolide, has shown anti-cancer properties in various cancers including breast cancer, but its effects in ovarian cancer remain unexplored. Notch 1 and Notch3 are critically involved in ovarian cancer progression. We decided to examine the effects of Withaferin A in ovarian carcinoma cell lines and its molecular mechanism of action including its regulation of Notch. The effects of Withaferin A were examined in CaOV3 and SKOV3 ovarian carcinoma cell lines using MTS assay, clonogenic assay, annexin V/propidium iodide flow cytometry, and cell cycle analysis. Western analysis was conducted to examine the molecular mechanisms of action. Withaferin A inhibited the growth and colony formation of CaOV3 and SKOV3 cells by inducing apoptosis and cell cycle arrest. These changes correlated with down-regulation of Notch1, Notch3, cdc25C, total and phosphorylated Akt, and bcl-2 proteins. Withaferin A inhibits CaOV3 and SKOV3 ovarian carcinoma cell growth, at least in part by targeting Notch1 and Notch3. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. BMPs and FGFs target Notch signalling via jagged 2 to regulate tooth morphogenesis and cytodifferentiation

    PubMed Central

    Mitsiadis, Thimios A.; Graf, Daniel; Luder, Hansueli; Gridley, Thomas; Bluteau, Gilles

    2010-01-01

    The Notch signalling pathway is an evolutionarily conserved intercellular signalling mechanism that is essential for cell fate specification and proper embryonic development. We have analysed the expression, regulation and function of the jagged 2 (Jag2) gene, which encodes a ligand for the Notch family of receptors, in developing mouse teeth. Jag2 is expressed in epithelial cells that give rise to the enamel-producing ameloblasts from the earliest stages of tooth development. Tissue recombination experiments showed that its expression in epithelium is regulated by mesenchyme-derived signals. In dental explants cultured in vitro, the local application of fibroblast growth factors upregulated Jag2 expression, whereas bone morphogenetic proteins provoked the opposite effect. Mice homozygous for a deletion in the Notch-interaction domain of Jag2 presented a variety of severe dental abnormalities. In molars, the crown morphology was misshapen, with additional cusps being formed. This was due to alterations in the enamel knot, an epithelial signalling structure involved in molar crown morphogenesis, in which Bmp4 expression and apoptosis were altered. In incisors, cytodifferentiation and enamel matrix deposition were inhibited. The expression of Tbx1 in ameloblast progenitors, which is a hallmark for ameloblast differentiation and enamel formation, was dramatically reduced in Jag2−/− teeth. Together, these results demonstrate that Notch signalling mediated by Jag2 is indispensable for normal tooth development. PMID:20685737

  1. Breast Cancer Stem Cell Therapeutics, Multiple Strategies Versus Using Engineered Mesenchymal Stem Cells With Notch Inhibitory Properties: Possibilities and Perspectives.

    PubMed

    Bose, Bipasha; Sen, Utsav; Shenoy P, Sudheer

    2018-01-01

    Relapse cases of cancers are more vigorous and difficult to control due to the preponderance of cancer stem cells (CSCs). Such CSCs that had been otherwise dormant during the first incidence of cancer gradually appear as radiochemoresistant cancer cells. Hence, cancer therapeutics aimed at CSCs would be an effective strategy for mitigating the cancers during relapse. Alternatively, CSC therapy can also be proposed as an adjuvant therapy, along-with the conventional therapies. As regenerative stem cells (RSCs) are known for their trophic effects, anti-tumorogenicity, and better migration toward an injury site, this review aims to address the use of adult stem cells such as dental pulp derived; cord blood derived pure populations of regenerative stem cells for targeting CSCs. Indeed, pro-tumorogenicity of RSCs is of concern and hence has also been dealt with in relation to breast CSC therapeutics. Furthermore, as notch signaling pathways are upregulated in breast cancers, and anti-notch antibody based and sh-RNA based therapies are already in the market, this review focuses the possibilities of engineering RSCs to express notch inhibitory proteins for breast CSC therapeutics. Also, we have drawn a comparison among various possibilities of breast CSC therapeutics, about, notch1 inhibition. J. Cell. Biochem. 119: 141-149, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  2. Curcumin inhibits cancer progression through regulating expression of microRNAs.

    PubMed

    Zhou, Siying; Zhang, Sijie; Shen, Hongyu; Chen, Wei; Xu, Hanzi; Chen, Xiu; Sun, Dawei; Zhong, Shanliang; Zhao, Jianhua; Tang, Jinhai

    2017-02-01

    Curcumin, a major yellow pigment and spice in turmeric and curry, is a powerful anti-cancer agent. The anti-tumor activities of curcumin include inhibition of tumor proliferation, angiogenesis, invasion and metastasis, induction of tumor apoptosis, increase of chemotherapy sensitivity, and regulation of cell cycle and cancer stem cell, indicating that curcumin maybe a strong therapeutic potential through modulating various cancer progression. It has been reported that microRNAs as small noncoding RNA molecules are related to cancer progression, which can be regulated by curcumin. Dysregulated microRNAs play vital roles in tumor biology via regulating expressions of target genes and then influencing multiple cancer-related signaling pathways. In this review, we focused on the inhibition effect of curcumin on various cancer progression by regulating expression of multiple microRNAs. Curcumin-induced dysregulation of microRNAs may activate or inactivate a set of signaling pathways, such as Akt, Bcl-2, PTEN, p53, Notch, and Erbb signaling pathways. A better understanding of the relation between curcumin and microRNAs may provide a potential therapeutic target for various cancers.

  3. Notch signaling sustains the expression of Mcl-1 and the activity of eIF4E to promote cell survival in CLL

    PubMed Central

    De Falco, Filomena; Sabatini, Rita; Del Papa, Beatrice; Falzetti, Franca; Di Ianni, Mauro; Sportoletti, Paolo; Baldoni, Stefano; Screpanti, Isabella; Marconi, Pierfrancesco; Rosati, Emanuela

    2015-01-01

    In chronic lymphocytic leukemia (CLL), Notch1 and Notch2 signaling is constitutively activated and contributes to apoptosis resistance. We show that genetic inhibition of either Notch1 or Notch2, through small-interfering RNA, increases apoptosis of CLL cells and is associated with decreased levels of the anti-apoptotic protein Mcl-1. Thus, Notch signaling promotes CLL cell survival at least in part by sustaining Mcl-1 expression. In CLL cells, an enhanced Notch activation also contributes to the increase in Mcl-1 expression and cell survival induced by IL-4. Mcl-1 downregulation by Notch targeting is not due to reduced transcription or degradation by caspases, but in part, to increased degradation by the proteasome. Mcl-1 downregulation by Notch targeting is also accompanied by reduced phosphorylation of eukaryotic translation initiation factor 4E (eIF4E), suggesting that this protein is another target of Notch signaling in CLL cells. Overall, we show that Notch signaling sustains CLL cell survival by promoting Mcl-1 expression and eIF4E activity, and given the oncogenic role of these factors, we underscore the therapeutic potential of Notch inhibition in CLL. PMID:26041884

  4. Drosophila melanogaster auxilin regulates the internalization of Delta to control activity of the Notch signaling pathway

    PubMed Central

    Hagedorn, Elliott J.; Bayraktar, Jennifer L.; Kandachar, Vasundhara R.; Bai, Ting; Englert, Dane M.; Chang, Henry C.

    2006-01-01

    We have isolated mutations in the Drosophila melanogaster homologue of auxilin, a J-domain–containing protein known to cooperate with Hsc70 in the disassembly of clathrin coats from clathrin-coated vesicles in vitro. Consistent with this biochemical role, animals with reduced auxilin function exhibit genetic interactions with Hsc70 and clathrin. Interestingly, the auxilin mutations interact specifically with Notch and disrupt several Notch-mediated processes. Genetic evidence places auxilin function in the signal-sending cells, upstream of Notch receptor activation, suggesting that the relevant cargo for this auxilin-mediated endocytosis is the Notch ligand Delta. Indeed, the localization of Delta protein is disrupted in auxilin mutant tissues. Thus, our data suggest that auxilin is an integral component of the Notch signaling pathway, participating in the ubiquitin-dependent endocytosis of Delta. Furthermore, the fact that auxilin is required for Notch signaling suggests that ligand endocytosis in the signal-sending cells needs to proceed past coat disassembly to activate Notch. PMID:16682530

  5. Notch Inhibition Induces Cochlear Hair Cell Regeneration and Recovery of Hearing after Acoustic Trauma

    PubMed Central

    Mizutari, Kunio; Fujioka, Masato; Hosoya, Makoto; Bramhall, Naomi; Okano, Hirotaka James; Okano, Hideyuki; Edge, Albert S.B.

    2013-01-01

    SUMMARY Hearing loss due to damage to auditory hair cells is normally irreversible because mammalian hair cells do not regenerate. Here, we show that new hair cells can be induced and can cause partial recovery of hearing in ears damaged by noise trauma, when Notch signaling is inhibited by a γ-secretase inhibitor selected for potency in stimulating hair cell differentiation from inner ear stem cells in vitro. Hair cell generation resulted from an increase in the level of bHLH transcription factor, Atoh1, in response to inhibition of Notch signaling. In vivo prospective labeling of Sox2-expressing cells with a Cre/lox system unambiguously demonstrated that hair cell generation resulted from transdifferentiation of supporting cells. Manipulating cell fate of cochlear sensory cells in vivo by pharmacological inhibition of Notch signaling is thus a potential therapeutic approach to the treatment of deafness. PMID:23312516

  6. A Wingless and Notch double-repression mechanism regulates G1–S transition in the Drosophila wing

    PubMed Central

    Herranz, Héctor; Pérez, Lidia; Martín, Francisco A; Milán, Marco

    2008-01-01

    The control of tissue growth and patterning is orchestrated in various multicellular tissues by the coordinated activity of the signalling molecules Wnt/Wingless (Wg) and Notch, and mutations in these pathways can cause cancer. The role of these molecules in the control of cell proliferation and the crosstalk between their corresponding pathways remain poorly understood. Crosstalk between Notch and Wg has been proposed to organize pattern and growth in the Drosophila wing primordium. Here we report that Wg and Notch act in a surprisingly linear pathway to control G1–S progression. We present evidence that these molecules exert their function by regulating the expression of the dmyc proto-oncogene and the bantam micro-RNA, which positively modulated the activity of the E2F transcription factor. Our results demonstrate that Notch acts in this cellular context as a repressor of cell-cycle progression and Wg has a permissive role in alleviating Notch-mediated repression of G1–S progression in wing cells. PMID:18451803

  7. Activation of Dll4/Notch Signaling and Hypoxia-Inducible Factor-1 Alpha Facilitates Lymphangiogenesis in Lacrimal Glands in Dry Eye.

    PubMed

    Min, Ji Hwan; Lee, Chul Hee; Ji, Yong Woo; Yeo, Areum; Noh, Hyemi; Song, Insil; Kim, Eung Kweon; Lee, Hyung Keun

    2016-01-01

    By using hypoxia-inducible factor-1 alpha conditional knockout (HIF-1α CKO) mice and a dry eye (DE) mouse model, we aimed to determine the role played by delta-like ligand 4 (Dll4)/Notch signaling and HIF-1α in the lymphangiogenesis of lacrimal glands (LGs). C57BL/6 mice were housed in a controlled-environment chamber for DE induction. During DE induction, the expression level of Dll4/Notch signaling and lymphangiogenesis in LGs was measured by quantitative RT-PCR, immunoblot, and immunofluorescence staining. Next, lymphangiogenesis was measured after Dll4/Notch signal inhibition by anti-Dll4 antibody or γ-secretase inhibitor. Using HIF-1α CKO mice, the expression of Dll4/Notch signaling and lymphangiogenesis in LGs of DE-induced HIF-1α CKO mice were assessed. Additionally, the infiltration of CD45+ cells in LGs was assessed by immunohistochemical (IHC) staining and flow cytometry for each condition. DE significantly upregulated Dll4/Notch and lymphangiogenesis in LGs. Inhibition of Dll4/Notch significantly suppressed lymphangiogenesis in LGs. Compared to wild-type (WT) mice, DE induced HIF-1α CKO mice showed markedly low levels of Dll4/Notch and lymphangiogenesis. Inhibition of lymphangiogenesis by Dll4/Notch suppression resulted in increased CD45+ cell infiltration in LGs. Likewise, CD45+ cells infiltrated more in the LGs of HIF-1α CKO DE mice than in non-DE HIF-1α CKO mice. Dll4/Notch signaling and HIF-1α are closely related to lymphangiogenesis in DE-induced LGs. Lymphangiogenesis stimulated by Dll4/Notch and HIF-1α may play a role in protecting LGs from DE-induced inflammation by aiding the clearance of immune cells from LGs.

  8. Notch Signaling Contributes to Liver Inflammation by Regulation of Interleukin-22-Producing Cells in Hepatitis B Virus Infection

    PubMed Central

    Wei, Xin; Wang, Jiu-Ping; Hao, Chun-Qiu; Yang, Xiao-Fei; Wang, Lin-Xu; Huang, Chang-Xing; Bai, Xue-Fan; Lian, Jian-Qi; Zhang, Ye

    2016-01-01

    The mechanism of hepatitis B virus (HBV) induced liver inflammation is not fully elucidated. Notch signaling augmented interleukin (IL)-22 secretion in CD4+ T cells, and Notch-IL-22 axis fine-tuned inflammatory response. We previously demonstrated a proinflammatory role of IL-22 in HBV infection. Thus, in this study, we analyzed the role of Notch in development of IL-22-producing cells in HBV infection by inhibition of Notch signaling using γ-secretase inhibitor DAPT in both hydrodynamic induced HBV-infected mouse model and in peripheral blood cells isolated from patients with HBV infection. mRNA expressions of Notch1 and Notch2 were significantly increased in livers and CD4+ T cells upon HBV infection. Inhibition of Notch signaling in vivo leaded to the reduction in NKp46+ innate lymphoid cells 22 (ILC22) and lymphoid tissue inducer 4 (LTi4) cells in the liver. This process was accompanied by downregulating the expressions of IL-22 and related proinflammatory cytokines and chemokines in the liver, as well as blocking the recruitment of antigen-non-specific inflammatory cells into the liver and subsequent liver injury, but did not affect HBV antigens production and IL-22 secretion in the serum. Furthermore, IL-22 production in HBV non-specific cultured CD4+ T cells, but not HBV-specific CD4+ T cells, was reduced in response to in vitro inhibition of Notch signaling. In conclusion, Notch siganling appears to be an important mediator of the liver inflammation by modulating hepatic ILC22. The potential proinflammatory effect of Notch-mediated ILC22 may be significant for the development of new therapeutic approaches for treatment of hepatitis B. PMID:27800305

  9. Naringin Stimulates Osteogenic Differentiation of Rat Bone Marrow Stromal Cells via Activation of the Notch Signaling Pathway

    PubMed Central

    Yu, Guo-yong; Zheng, Gui-zhou; Chang, Bo; Hu, Qin-xiao; Lin, Fei-xiang; Liu, De-zhong; Wu, Chu-cheng; Du, Shi-xin

    2016-01-01

    Naringin is a major flavonoid found in grapefruit and is an active compound extracted from the Chinese herbal medicine Rhizoma Drynariae. Naringin is a potent stimulator of osteogenic differentiation and has potential application in preventing bone loss. However, the signaling pathway underlying its osteogenic effect remains unclear. We hypothesized that the osteogenic activity of naringin involves the Notch signaling pathway. Rat bone marrow stromal cells (BMSCs) were cultured in osteogenic medium containing-naringin, with or without DAPT (an inhibitor of Notch signaling), the effects on ALP activity, calcium deposits, osteogenic genes (ALP, BSP, and cbfa1), adipogenic maker gene PPARγ2 levels, and Notch expression were examined. We found that naringin dose-dependently increased ALP activity and Alizarin red S staining, and treatment at the optimal concentration (50 μg/mL) increased mRNA levels of osteogenic genes and Notch1 expression, while decreasing PPARγ2 mRNA levels. Furthermore, treatment with DAPT partly reversed effects of naringin on BMSCs, as judged by decreases in naringin-induced ALP activity, calcium deposits, and osteogenic genes expression, as well as upregulation of PPARγ2 mRNA levels. These results suggest that the osteogenic effect of naringin partly involves the Notch signaling pathway. PMID:27069482

  10. Notch signaling is a potent inducer of growth arrest and apoptosis in a wide range of B-cell malignancies

    PubMed Central

    Zweidler-McKay, Patrick A.; He, Yiping; Xu, Lanwei; Rodriguez, Carlos G.; Karnell, Fredrick G.; Carpenter, Andrea C.; Aster, Jon C.; Allman, David; Pear, Warren S.

    2005-01-01

    Although Notch receptor expression on malignant B cells is widespread, the effect of Notch signaling in these cells is poorly understood. To investigate Notch signaling in B-cell malignancy, we assayed the effect of Notch activation in multiple murine and human B-cell tumors, representing both immature and mature subtypes. Expression of constitutively active, truncated forms of the 4 mammalian Notch receptors (ICN1-4) inhibited growth and induced apoptosis in both murine and human B-cell lines but not T-cell lines. Similar results were obtained in human precursor B-cell acute lymphoblastic leukemia lines when Notch activation was achieved by coculture with fibroblasts expressing the Notch ligands Jagged1 or Jagged2. All 4 truncated Notch receptors, as well as the Jagged ligands, induced Hes1 transcription. Retroviral expression of Hairy/Enhancer of Split-1 (Hes1) recapitulated the Notch effects, suggesting that Hes1 is an important mediator of Notch-induced growth arrest and apoptosis in B cells. Among the B-cell malignancies that were susceptible to Notch-mediated growth inhibition/apoptosis were mature B-cell and therapy-resistant B-cell malignancies, including Hodgkin, myeloma, and mixed-lineage leukemia (MLL)–translocated cell lines. These results suggest that therapies capable of activating Notch/Hes1 signaling may have therapeutic potential in a wide range of human B-cell malignancies. PMID:16118316

  11. Spontaneous Seizures and Altered Gene Expression in GABA Signaling Pathways in a mind bomb Mutant Zebrafish

    PubMed Central

    Hortopan, Gabriela A.; Dinday, Matthew T.; Baraban, Scott C.

    2010-01-01

    Disruption of E3 ubiquitin ligase activity in immature zebrafish mind bomb mutants, leads to a failure in Notch signaling, excessive numbers of neurons, and depletion of neural progenitor cells. This neurogenic phenotype is associated with defects in neural patterning and brain development. Because developmental brain abnormalities are recognized as an important feature of childhood neurological disorders such as epilepsy and autism, we determined whether zebrafish mutants with grossly abnormal brain structure exhibit spontaneous electrical activity that resembles the long-duration, high-amplitude multi-spike discharges reported in immature zebrafish exposed to convulsant drugs. Electrophysiological recordings from agar immobilized mind bomb mutants at three days postfertilization (dpf) confirmed the occurrence of electrographic seizure activity; seizure-like behaviors were also noted during locomotion video tracking of freely behaving mutants. To identify genes differentially expressed in the mind bomb mutant and provide insight into molecular pathways that may mediate these epileptic phenotypes, a transcriptome analysis was performed using microarray. Interesting candidate genes were further analyzed using conventional reverse transcriptasepolymerase chain reaction (RT-PCR) and real-time quantitative PCR (qPCR), as well as whole-mount in situ hybridization. Approximately 150 genes, some implicated in development, transcription, cell metabolism and signal transduction, are differentially regulated including down-regulation of several genes necessary for GABA-mediated signaling. These findings identify a collection of gene transcripts that may be responsible for the abnormal electrical discharge and epileptic activities observed in a mind bomb zebrafish mutant. This work may have important implications for neurological and neurodevelopmental disorders associated with mutations in ubiquitin ligase activity. Notch is an essential component of an evolutionarily conserved signal transduction cascade mediating development. In neuroectoderm, where cells have the potential to become neurons, activated Notch inhibits proneural gene expression in a process referred to as lateral inhibition. In the absence of Notch-mediated lateral inhibition, too many early-born cells differentiate into neurons (Chitnis et al., 1995; de la Pompa et al., 1997). Recent studies identified several E3 ligases that modulate Notch signaling through ubiquitin-dependent protein degradation and endocytosis (Lai, 2002). Ubiquitination, which occurs when an E3 ligase enzyme binds to both substrate and an E2 thioesterified protein (Deshaies and Joazeiro, 2009), is a key mechanism regulating many cellular processes. Mutation or small deletions within the ubiquitin E3A ligase gene in humans has been linked to autism spectrum disorders (Glessner et al., 2009) and Angelman syndrome, a neurogenetic disorder characterized by developmental delay, severe intellectual disability, absent speech, exuberant behavior, motor impairment, and epilepsy (Clayton-Smith and Laan, 2003). PMID:20943912

  12. Notch signaling: its roles and therapeutic potential in hematological malignancies

    PubMed Central

    Gu, Yisu

    2016-01-01

    Notch is a highly conserved signaling system that allows neighboring cells to communicate, thereby controlling their differentiation, proliferation and apoptosis, with the outcome of its activation being highly dependent on signal strength and cell type. As such, there is growing evidence that disturbances in physiological Notch signaling contribute to cancer development and growth through various mechanisms. Notch was first reported to contribute to tumorigenesis in the early 90s, through identification of the involvement of the Notch1 gene in the chromosomal translocation t(7;9)(q34;q34.3), found in a small subset of T-cell acute lymphoblastic leukemia. Since then, Notch mutations and aberrant Notch signaling have been reported in numerous other precursor and mature hematological malignancies, of both myeloid and lymphoid origin, as well as many epithelial tumor types. Of note, Notch has been reported to have both oncogenic and tumor suppressor roles, dependent on the cancer cell type. In this review, we will first give a general description of the Notch signaling pathway, and its physiologic role in hematopoiesis. Next, we will review the role of aberrant Notch signaling in several hematological malignancies. Finally, we will discuss current and potential future therapeutic approaches targeting this pathway. PMID:26934331

  13. Targeting Developmental Pathways: The Achilles Heel of Cancer?

    PubMed

    Dempke, Wolfram C M; Fenchel, Klaus; Uciechowski, Peter; Chevassut, Timothy

    2017-01-01

    Developmental pathways (e.g., Notch, Hippo, Hedgehog, Wnt, and TGF-β/BMP/FGF) are networks of genes that act co-ordinately to establish the body plan, and disruptions of genes in one pathway can have effects in related pathways and may result in serious dysmorphogenesis or cancer. Interestingly, all developmental pathways are highly conserved cell signalling systems present in almost all multicellular organisms. In addition, they have a crucial role in cell proliferation, apoptosis, differentiation, and finally in organ development. Of note, almost all of these pathways promote oncogenesis through synergistic associations with the Hippo signalling pathway, and several lines of evidence have also indicated that these pathways (e.g., Wnt/β-catenin) may be implicated in checkpoint inhibitor resistance (e.g., CTLA-4, PD-1, and PD-L1). Since Notch inhibition in vivo results in partial loss of its stemness features such as self-renewal, chemoresistance, invasive and migratory potential, and tumorigenesis, these highly conserved developmental pathways are regarded as being critical for regulation of self-renewal in both embryonic and adult stem cells and hence are likely to be implicated in the maintenance of cancer stem cells. Many small molecules are currently in preclinical and early clinical development, and only two compounds are approved for treatment of advanced or metastatic basal cell carcinoma (vismodegib and sonidegib). Furthermore, therapeutic targeting of cancer stem cells using drugs that disrupt activated developmental pathways may also represent an attractive strategy that is potentially relevant to many types of malignancy, notably blood cancers, where the evidence for leukaemia stem cells is well established. Future work will hopefully pave the way for the development of new strategies for targeting these pervasive oncogenic pathways. © 2017 S. Karger AG, Basel.

  14. Active form Notch4 promotes the proliferation and differentiation of 3T3-L1 preadipocytes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lai, Peng-Yeh; Tsai, Chong-Bin; Department of Ophthalmology, Chiayi Christian Hospital, Chiayi 600, Taiwan, ROC

    2013-01-18

    Highlights: ► Notch4IC modulates the ERK pathway and cell cycle to promote 3T3-L1 proliferation. ► Notch4IC facilitates 3T3-L1 differentiation by up-regulating proadipogenic genes. ► Notch4IC promotes proliferation during the early stage of 3T3-L1 adipogenesis. ► Notch4IC enhances differentiation during subsequent stages of 3T3-L1 adipogenesis. -- Abstract: Adipose tissue is composed of adipocytes, which differentiate from precursor cells in a process called adipogenesis. Many signal molecules are involved in the transcriptional control of adipogenesis, including the Notch pathway. Previous adipogenic studies of Notch have focused on Notch1 and HES1; however, the role of other Notch receptors in adipogenesis remains unclear. Q-RT-PCRmore » analyses showed that the augmentation of Notch4 expression during the differentiation of 3T3-L1 preadipocytes was comparable to that of Notch1. To elucidate the role of Notch4 in adipogenesis, the human active form Notch4 (N4IC) was transiently transfected into 3T3-L1 cells. The expression of HES1, Hey1, C/EBPδ and PPARγ was up-regulated, and the expression of Pref-1, an adipogenic inhibitor, was down-regulated. To further characterize the effect of N4IC in adipogenesis, stable cells expressing human N4IC were established. The expression of N4IC promoted proliferation and enhanced differentiation of 3T3-L1 cells compared with those of control cells. These data suggest that N4IC promoted proliferation through modulating the ERK pathway and the cell cycle during the early stage of 3T3-L1 adipogenesis and facilitated differentiation through up-regulating adipogenic genes such as C/EBPα, PPARγ, aP2, LPL and HSL during the middle and late stages of 3T3-L1 adipogenesis.« less

  15. Pancreatic islet regeneration through PDX-1/Notch-1/Ngn3 signaling after gastric bypass surgery in db/db mice

    PubMed Central

    Huang, Tao; Fu, Jun; Zhang, Zhijing; Zhang, Yuhao; Liang, Yunjia; Ge, Cuicui; Qin, Xianju

    2017-01-01

    In view of the compelling anti-diabetic effects of gastric bypass surgery (GBS) in the treatment of morbid obesity, it is important to clarify its enhancing effect on pancreatic islets, which is closely linked with diabetes remission in obese patients, as well as the underlying mechanisms. The present study evaluated the effects of GBS on glycemic control and other pancreatic changes in db/db mice. The db/db mice were divided into Control, Sham and GBS group. A significant improvement in fasting plasma glucose levels and glucose intolerance were observed post-surgery. At 4 weeks after surgery, further noteworthy changes were observed in the GBS group, including improved islet structure (revealed by immunohistochemical analysis), enhanced insulin secretion, pancreatic hyperplasia and a marked increase in the ratio of β-cells to non-β endocrine cells. Furthermore, notable changes in the levels of Notch-1, pancreatic and duodenal homeobox 1 (PDX-1) and neurogenin 3 (Ngn3) were observed in the GBS group, indicating a potential role of Notch signaling in pancreatic islet regeneration after surgery. In addition, results obtained in PDX-1 knockout (KO), Notch-1 KO and Ngn3 KO mouse models with GBS suggested that elevated PDX-1 resulted in the inhibition of Notch-1, further facilitated Ngn3 and thus promoted pancreatic β-cell regeneration after GBS. The present findings demonstrated that GBS in db/db mice resulted in pancreatic islet regeneration through the PDX-1/Notch-1/Ngn3 signaling pathway, which also reflected the important role of the gastrointestinal system in metabolism control. PMID:28966671

  16. LPS causes pericyte loss and microvascular dysfunction via disruption of Sirt3/angiopoietins/Tie-2 and HIF-2α/Notch3 pathways.

    PubMed

    Zeng, Heng; He, Xiaochen; Tuo, Qin-Hui; Liao, Duan-Fang; Zhang, Guo-Qiang; Chen, Jian-Xiong

    2016-02-12

    Recent studies reveal a crucial role of pericyte loss in sepsis-associated microvascular dysfunction. Sirtuin 3 (SIRT3) mediates histone protein post-translational modification related to aging and ischemic disease. This study investigated the involvement of SIRT3 in LPS-induced pericyte loss and microvascular dysfunction. Mice were exposed to LPS, expression of Sirt3, HIF-2α, Notch3 and angiopoietins/Tie-2, pericyte/endothelial (EC) coverage and vascular permeability were assessed. Mice treated with LPS significantly reduced the expression of SIRT3, HIF-2α and Notch3 in the lung. Furthermore, exposure to LPS increased Ang-2 while inhibited Ang-1/Tie-2 expression with a reduced pericyte/EC coverage. Intriguingly, knockout of Sirt3 upregulated Ang-2, but downregulated Tie-2 and HIF-2α/Notch3 expression which resulted in a dramatic reduction of pericyte/EC coverage and exacerbation of LPS-induced vascular leakage. Conversely, overexpression of Sirt3 reduced Ang-2 expression and increased Ang-1/Tie-2 and HIF-2α/Notch3 expression in the LPS treated mice. Overexpression of Sirt3 further prevented LPS-induced pericyte loss and vascular leakage. This was accompanied by a significant reduction of the mortality rate. Specific knockout of prolyl hydroxylase-2 (PHD2) increased HIF-2α/Notch3 expression, improved pericyte/EC coverage and reduced the mortality rate in the LPS-treated mice. Our study demonstrates the importance of SIRT3 in preserving vascular integrity by targeting pericytes in the setting of LPS-induced sepsis.

  17. SNX27 Deletion Causes Hydrocephalus by Impairing Ependymal Cell Differentiation and Ciliogenesis

    PubMed Central

    Zhou, Ying; Wang, Jian; Tseng, I-Chu; Huang, Timothy; Zhao, Yingjun; Zheng, Qiuyang; Gao, Yue; Luo, Hong; Zhang, Xian; Bu, Guojun; Hong, Wanjin

    2016-01-01

    Hydrocephalus is a brain disorder derived from CSF accumulation due to defects in CSF clearance. Although dysfunctional apical cilia in the ependymal cell layer are causal to the onset of hydrocephalus, mechanisms underlying proper ependymal cell differentiation are largely unclear. SNX27 is a trafficking component required for normal brain function and was shown previously to suppress γ-secretase-dependent amyloid precursor protein and Notch cleavage. However, it was unclear how SNX27-dependent γ-secretase inhibition could contribute to brain development and pathophysiology. Here, we describe and characterize an Snx27-deleted mouse model for the ependymal layer defects of deciliation and hydrocephalus. SNX27 deficiency results in reductions in ependymal cells and cilia density, as well as severe postnatal hydrocephalus. Inhibition of Notch intracellular domain signaling with γ-secretase inhibitors reversed ependymal cells/cilia loss and dilation of lateral ventricles in Snx27-deficient mice, giving strong indication that Snx27 deletion triggers defects in ependymal layer formation and ciliogenesis through Notch hyperactivation. Together, these results suggest that SNX27 is essential for ependymal cell differentiation and ciliogenesis, and its deletion can promote hydrocephalus pathogenesis. SIGNIFICANCE STATEMENT Down's syndrome (DS) in humans and mouse models has been shown previously to confer a high risk for the development of pathological hydrocephalus. Because we have previously described SNX27 as a component that is consistently downregulated in DS, we present here a robust Snx27-deleted mouse model that produces hydrocephalus and associated ciliary defects with complete penetrance. In addition, we find that γ-secretase/Notch modulation may be a candidate drug target in SNX27-associated hydrocephalus such as that observed in DS. Based on these findings, we anticipate that future study will determine whether modulation of a SNX27/Notch/γ-secretase pathway can also be of therapeutic interest to congenital hydrocephalus. PMID:27974614

  18. SNX27 Deletion Causes Hydrocephalus by Impairing Ependymal Cell Differentiation and Ciliogenesis.

    PubMed

    Wang, Xin; Zhou, Ying; Wang, Jian; Tseng, I-Chu; Huang, Timothy; Zhao, Yingjun; Zheng, Qiuyang; Gao, Yue; Luo, Hong; Zhang, Xian; Bu, Guojun; Hong, Wanjin; Xu, Huaxi

    2016-12-14

    Hydrocephalus is a brain disorder derived from CSF accumulation due to defects in CSF clearance. Although dysfunctional apical cilia in the ependymal cell layer are causal to the onset of hydrocephalus, mechanisms underlying proper ependymal cell differentiation are largely unclear. SNX27 is a trafficking component required for normal brain function and was shown previously to suppress γ-secretase-dependent amyloid precursor protein and Notch cleavage. However, it was unclear how SNX27-dependent γ-secretase inhibition could contribute to brain development and pathophysiology. Here, we describe and characterize an Snx27-deleted mouse model for the ependymal layer defects of deciliation and hydrocephalus. SNX27 deficiency results in reductions in ependymal cells and cilia density, as well as severe postnatal hydrocephalus. Inhibition of Notch intracellular domain signaling with γ-secretase inhibitors reversed ependymal cells/cilia loss and dilation of lateral ventricles in Snx27-deficient mice, giving strong indication that Snx27 deletion triggers defects in ependymal layer formation and ciliogenesis through Notch hyperactivation. Together, these results suggest that SNX27 is essential for ependymal cell differentiation and ciliogenesis, and its deletion can promote hydrocephalus pathogenesis. Down's syndrome (DS) in humans and mouse models has been shown previously to confer a high risk for the development of pathological hydrocephalus. Because we have previously described SNX27 as a component that is consistently downregulated in DS, we present here a robust Snx27-deleted mouse model that produces hydrocephalus and associated ciliary defects with complete penetrance. In addition, we find that γ-secretase/Notch modulation may be a candidate drug target in SNX27-associated hydrocephalus such as that observed in DS. Based on these findings, we anticipate that future study will determine whether modulation of a SNX27/Notch/γ-secretase pathway can also be of therapeutic interest to congenital hydrocephalus. Copyright © 2016 the authors 0270-6474/16/3612586-12$15.00/0.

  19. Integrated β-catenin, BMP, PTEN, and Notch signalling patterns the nephron

    PubMed Central

    Lindström, Nils O; Lawrence, Melanie L; Burn, Sally F; Johansson, Jeanette A; Bakker, Elvira RM; Ridgway, Rachel A; Chang, C-Hong; Karolak, Michele J; Oxburgh, Leif; Headon, Denis J; Sansom, Owen J; Smits, Ron; Davies, Jamie A; Hohenstein, Peter

    2015-01-01

    The different segments of the nephron and glomerulus in the kidney balance the processes of water homeostasis, solute recovery, blood filtration, and metabolite excretion. When segment function is disrupted, a range of pathological features are presented. Little is known about nephron patterning during embryogenesis. In this study, we demonstrate that the early nephron is patterned by a gradient in β-catenin activity along the axis of the nephron tubule. By modifying β-catenin activity, we force cells within nephrons to differentiate according to the imposed β-catenin activity level, thereby causing spatial shifts in nephron segments. The β-catenin signalling gradient interacts with the BMP pathway which, through PTEN/PI3K/AKT signalling, antagonises β-catenin activity and promotes segment identities associated with low β-catenin activity. β-catenin activity and PI3K signalling also integrate with Notch signalling to control segmentation: modulating β-catenin activity or PI3K rescues segment identities normally lost by inhibition of Notch. Our data therefore identifies a molecular network for nephron patterning. DOI: http://dx.doi.org/10.7554/eLife.04000.001 PMID:25647637

  20. Expression of Notch pathway genes in mammalian epidermis and modulation by beta-catenin.

    PubMed

    Ambler, Carrie A; Watt, Fiona M

    2007-06-01

    The Notch pathway is required for hair follicle maintenance and is activated through beta-catenin induced transcription of the Notch ligand Jagged1. We show that hair follicles in the resting phase express low levels of Jagged1 and Hes1, and other Notch target genes are undetectable. In growing (anagen) follicles, Jagged1 and Hes1 expression increases, Hes5 and HeyL are expressed in distinct cell layers, and Hey2 is expressed in the dermal papilla. When beta-catenin is activated by means of an inducible transgene, Jagged1, Hes1, Hes5, HeyL, and Hey2 are up-regulated, the sites of expression being the same in beta-catenin induced ectopic follicles as in anagen follicles. beta-Catenin also induces Hey1 in dermal papilla cells. beta-Catenin-induced up-regulation of Jagged1 precedes induction of other Notch target genes. The different sites of expression of Hes and Hey genes suggest input from additional signaling pathways. Copyright 2007 Wiley-Liss, Inc.

  1. Manipulation of a VEGF-Notch signaling circuit drives formation of functional vascular endothelial progenitors from human pluripotent stem cells

    PubMed Central

    Sahara, Makoto; Hansson, Emil M; Wernet, Oliver; Lui, Kathy O; Später, Daniela; Chien, Kenneth R

    2014-01-01

    Human pluripotent stem cell (hPSC)-derived endothelial lineage cells constitutes a promising source for therapeutic revascularization, but progress in this arena has been hampered by a lack of clinically-scalable differentiation protocols and inefficient formation of a functional vessel network integrating with the host circulation upon transplantation. Using a human embryonic stem cell reporter cell line, where green fluorescent protein expression is driven by an endothelial cell-specific VE-cadherin (VEC) promoter, we screened for > 60 bioactive small molecules that would promote endothelial differentiation, and found that administration of BMP4 and a GSK-3β inhibitor in an early phase and treatment with VEGF-A and inhibition of the Notch signaling pathway in a later phase led to efficient differentiation of hPSCs to the endothelial lineage within six days. This sequential approach generated > 50% conversion of hPSCs to endothelial cells (ECs), specifically VEC+CD31+CD34+CD14−KDRhigh endothelial progenitors (EPs) that exhibited higher angiogenic and clonogenic proliferation potential among endothelial lineage cells. Pharmaceutical inhibition or genetical knockdown of Notch signaling, in combination with VEGF-A treatment, resulted in efficient formation of EPs via KDR+ mesodermal precursors and blockade of the conversion of EPs to mature ECs. The generated EPs successfully formed functional capillary vessels in vivo with anastomosis to the host vessels when transplanted into immunocompromised mice. Manipulation of this VEGF-A-Notch signaling circuit in our protocol leads to rapid large-scale production of the hPSC-derived EPs by 12- to 20-fold vs current methods, which may serve as an attractive cell population for regenerative vascularization with superior vessel forming capability compared to mature ECs. PMID:24810299

  2. Functional studies on the role of Notch signaling in Hydractinia development.

    PubMed

    Gahan, James M; Schnitzler, Christine E; DuBuc, Timothy Q; Doonan, Liam B; Kanska, Justyna; Gornik, Sebastian G; Barreira, Sofia; Thompson, Kerry; Schiffer, Philipp; Baxevanis, Andreas D; Frank, Uri

    2017-08-01

    The function of Notch signaling was previously studied in two cnidarians, Hydra and Nematostella, representing the lineages Hydrozoa and Anthozoa, respectively. Using pharmacological inhibition in Hydra and a combination of pharmacological and genetic approaches in Nematostella, it was shown in both animals that Notch is required for tentacle morphogenesis and for late stages of stinging cell maturation. Surprisingly, a role for Notch in neural development, which is well documented in bilaterians, was evident in embryonic Nematostella but not in adult Hydra. Adult neurogenesis in the latter seemed to be unaffected by DAPT, a drug that inhibits Notch signaling. To address this apparent discrepancy, we studied the role of Notch in Hydractinia echinata, an additional hydrozoan, in all life stages. Using CRISPR-Cas9 mediated mutagenesis, transgenesis, and pharmacological interference we show that Notch is dispensable for Hydractinia normal neurogenesis in all life stages but is required for the maturation of stinging cells and for tentacle morphogenesis. Our results are consistent with a conserved role for Notch in morphogenesis and nematogenesis across Cnidaria, and a lineage-specific loss of Notch dependence in neurogenesis in hydrozoans. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Opposing activities of Notch and Wnt signaling regulate intestinal stem cells and gut homeostasis

    PubMed Central

    Tian, Hua; Biehs, Brian; Chiu, Cecilia; Siebel, Chris; Wu, Yan; Costa, Mike; de Sauvage, Frederic J.; Klein, Ophir D.

    2015-01-01

    Summary Proper organ homeostasis requires tight control of adult stem cells and differentiation through integration of multiple inputs. In the mouse small intestine, Notch and Wnt signaling are required both for stem cell maintenance and for a proper balance of differentiation between secretory and absorptive cell lineages. In the absence of Notch signaling, stem cells preferentially generate secretory cells at the expense of absorptive cells. Here, we use function-blocking antibodies against Notch receptors to demonstrate that Notch blockade perturbs intestinal stem cell function by causing a de-repression of the Wnt signaling pathway, leading to mis-expression of prosecretory genes. Importantly, attenuation of the Wnt pathway rescued the phenotype associated with Notch blockade. These studies bring to light a negative regulatory mechanism that maintains stem cell activity and balanced differentiation, and we propose that the interaction between Wnt and Notch signaling described here represents a common theme in adult stem cell biology. PMID:25818302

  4. Crocodile choline from Crocodylus siamensis induces apoptosis of human gastric cancer.

    PubMed

    Mao, Xiao-Mei; Fu, Qi-Rui; Li, Hua-Liang; Zheng, Ya-Hui; Chen, Shu-Ming; Hu, Xin-Yi; Chen, Qing-Xi; Chen, Qiong-Hua

    2017-03-01

    Crocodile choline, an active compound isolated from Crocodylus siamensis, was found to exert potent anti-cancer activities against human gastric cancer cells in vitro and in vivo. Our study revealed that crocodile choline led to cell cycle arrest at the G2/M phase through attenuating the expressions of cyclins, Cyclin B1, and CDK-1. Furthermore, crocodile choline accelerated apoptosis through the mitochondrial apoptotic pathway with the decrease in mitochondrial membrane potential, the increase in reactive oxygen species production and Bax/Bcl-2 ratio, and the activation of caspase-3 along with the release of cytochrome c. In addition, this study, for the first time, shows that Notch pathway is remarkably deregulated by crocodile choline. The combination of crocodile choline and Notch1 short interfering RNA led to dramatically increased cytotoxicity than observed with either agent alone. Notch1 short interfering RNA sensitized and potentiated the capability of crocodile choline to suppress the cell progression and invasion of gastric cancer. Taken together, these data suggested that crocodile choline was a potent progression inhibitor of gastric cancer cells, which was correlated with mitochondrial apoptotic pathway and Notch pathway. Combining Notch1 inhibitors with crocodile choline might represent a novel approach for gastric cancer.

  5. Dai-Zong-Fang, A Traditional Chinese Herbal Formula, Ameliorates Insulin Resistance in db/db Mice.

    PubMed

    Zhu, Lili; Zhu, Xiaoyun; Sun, Guibo; Meng, Xiangbao; Wang, Min; Cui, Hanming; Wang, Jialong; Zhai, Yadong; Yang, Ke; Tang, Yang; Sun, Xiaobo; Liu, Ximing

    2018-01-01

    Intricate health problems, such as insulin resistance (IR) and its associated diseases, call for multi-targeted therapies with few side effects. Based on traditional Chinese medicine (TCM), Dai-Zong-Fang (DZF) is an herbal formula mainly composed of Rhizoma Coptidis (Huanglian) and Fructus Aurantii Immaturus (Zhishi), of which berberine and naringin are the main constituents. Though DZF has been clinically used for treatment of IR and metabolic syndrome for decades, its mechanism in vivo remains unknown. In the present study, we observed that both DZF and metformin, the first-line drug for type 2 diabetes, ameliorated insulin resistance with significant improvement of oral glucose tolerance test (OGTT) and homeostasis model assessment of IR (HOMA-IR) level in diabetic C57BL/Ksj-Lepr db -/- ( db/db ) mice. Low-density lipoprotein cholesterol (LDL-C) and fatty acids (FAs) also decreased in the blood. Higher dose of DZF (1 g·kg -1 ), but not metformin (0.25 g·kg -1 ), alleviated hepatic steatosis with reduced liver weight and hepatic lipid accumulation and provided protection from hepatic injury with lower alanine aminotransferase and aspartate aminotransferase and increased hepatic superoxide dismutase activity in db/db mice. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) showed a decrease in FA synthase gene ( Fasn ) and an increase in FA oxidation gene Ppara expression. Western blot demonstrated that both DZF and metformin activated 5' AMP-activated protein kinase (AMPK) but inhibited Notch intracellular domain (NICD) and Hairy/enhancer-of-split 1 (Hes1) of Notch signaling pathway in the liver. DZF also dramatically improved the ultrastructure of skeletal muscles, AMPK phosphorylation, and GLUT4 translocation. DZF also promoted FA transport and oxidation with Cd36 and Cpt1b up-regulation in the skeletal muscle. In conclusion, DZF improves insulin sensitivity by reducing hepatic lipids through AMPK activation and Notch signal pathway inhibition and enhancing energy metabolism in the skeletal muscle via AMPK. This study provides insights into the treatment of complex conditions, such as IR, where TCM herbal formulas exert multipronged effects through correlating pathways.

  6. The Murine Ortholog of Notchless, a Direct Regulator of the Notch Pathway in Drosophila melanogaster, Is Essential for Survival of Inner Cell Mass Cells

    PubMed Central

    Cormier, Sarah; Le Bras, Stéphanie; Souilhol, Céline; Vandormael-Pournin, Sandrine; Durand, Béatrice; Babinet, Charles; Baldacci, Patricia; Cohen-Tannoudji, Michel

    2006-01-01

    Notch signaling is an evolutionarily conserved pathway involved in intercellular communication and is essential for proper cell fate choices. Numerous genes participate in the modulation of the Notch signaling pathway activity. Among them, Notchless (Nle) is a direct regulator of the Notch activity identified in Drosophila melanogaster. Here, we characterized the murine ortholog of Nle and demonstrated that it has conserved the ability to modulate Notch signaling. We also generated mice deficient for mouse Nle (mNle) and showed that its disruption resulted in embryonic lethality shortly after implantation. In late mNle−/− blastocysts, inner cell mass (ICM) cells died through a caspase 3-dependent apoptotic process. Most deficient embryos exhibited a delay in the temporal down-regulation of Oct4 expression in the trophectoderm (TE). However, mNle-deficient TE was able to induce decidual swelling in vivo and properly differentiated in vitro. Hence, our results indicate that mNle is mainly required in ICM cells, being instrumental for their survival, and raise the possibility that the death of mNle-deficient embryos might result from abnormal Notch signaling during the first steps of development. PMID:16611995

  7. The murine ortholog of notchless, a direct regulator of the notch pathway in Drosophila melanogaster, is essential for survival of inner cell mass cells.

    PubMed

    Cormier, Sarah; Le Bras, Stéphanie; Souilhol, Céline; Vandormael-Pournin, Sandrine; Durand, Béatrice; Babinet, Charles; Baldacci, Patricia; Cohen-Tannoudji, Michel

    2006-05-01

    Notch signaling is an evolutionarily conserved pathway involved in intercellular communication and is essential for proper cell fate choices. Numerous genes participate in the modulation of the Notch signaling pathway activity. Among them, Notchless (Nle) is a direct regulator of the Notch activity identified in Drosophila melanogaster. Here, we characterized the murine ortholog of Nle and demonstrated that it has conserved the ability to modulate Notch signaling. We also generated mice deficient for mouse Nle (mNle) and showed that its disruption resulted in embryonic lethality shortly after implantation. In late mNle(-/-) blastocysts, inner cell mass (ICM) cells died through a caspase 3-dependent apoptotic process. Most deficient embryos exhibited a delay in the temporal down-regulation of Oct4 expression in the trophectoderm (TE). However, mNle-deficient TE was able to induce decidual swelling in vivo and properly differentiated in vitro. Hence, our results indicate that mNle is mainly required in ICM cells, being instrumental for their survival, and raise the possibility that the death of mNle-deficient embryos might result from abnormal Notch signaling during the first steps of development.

  8. Notch signaling proteins HES-1 and Hey-1 bind to insulin degrading enzyme (IDE) proximal promoter and repress its transcription and activity: Implications for cellular Aβ metabolism

    PubMed Central

    Leal, María C.; Surace, Ezequiel I.; Holgado, María P.; Ferrari, Carina C.; Tarelli, Rodolfo; Pitossi, Fernando; Wisniewski, Thomas; Castaño, Eduardo M.; Morelli, Laura

    2012-01-01

    Cerebral amyloid β (Aβ) accumulation is pathogenically associated with sporadic Alzheimer’s disease (SAD). BACE-1 is involved in Aβ generation while insulin-degrading enzyme (IDE) partakes in Aβ proteolytic clearance. Vulnerable regions in AD brains show increased BACE-1 protein levels and enzymatic activity while the opposite occurs with IDE. Another common feature in SAD brains is Notch1 overexpression. Here we demonstrate an increase in mRNA levels of Hey-1, a Notch target gene, and a decrease of IDE transcripts in the hippocampus of SAD brains as compared to controls. Transient transfection of Notch intracellular domain (NICD) in N2aSW cells, mouse neuroblastoma cells (N2a) stably expressing human amyloid precursor protein (APP) Swedish mutation, reduce IDE mRNA levels, promoting extracellular Aβ accumulation. Also, NICD, HES-1 and Hey-1 overexpression result in decreased IDE proximal promoter activity. This effect was mediated by 2 functional sites located at −379/−372 and −310 −303 from the first translation start site in the −575/−19 (556 bp) fragment of IDE proximal promoter. By site-directed mutagenesis of the IDE promoter region we reverted the inhibitory effect mediated by NICD transfection suggesting that these sites are indeed responsible for the Notch-mediated inhibition of the IDE gene expression. Intracranial injection of the Notch ligand JAG-1 in Tg2576 mice, expressing the Swedish mutation in human APP, induced overexpression of HES-1 and Hey-1 and reduction of IDE mRNA levels, respectively. Our results support our theory that a Notch-dependent IDE transcriptional modulation may impact on Aβ metabolism providing a functional link between Notch signaling and the amyloidogenic pathway in SAD. PMID:22036964

  9. The Varied Roles of Notch in Cancer

    PubMed Central

    Aster, Jon C.; Pear, Warren S.; Blacklow, Stephen C.

    2018-01-01

    Notch receptors influence cellular behavior by participating in a seemingly simple signaling pathway, but outcomes produced by Notch signaling are remarkably varied depending on signal dose and cell context. Here, after briefly reviewing new insights into physiologic mechanisms of Notch signaling in healthy tissues and defects in Notch signaling that contribute to congenital disorders and viral infection, we discuss the varied roles of Notch in cancer, focusing on cell autonomous activities that may be either oncogenic or tumor suppressive. PMID:27959635

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Ren; Trindade, Alexandre; Instituto Gulbenkian de Ciencia, Oeiras

    Highlights: Black-Right-Pointing-Pointer Low dose Dll4-Fc increases vascular proliferation and overall perfusion. Black-Right-Pointing-Pointer Low dose Dll4-Fc helps vascular injury recovery in hindlimb ischemia model. Black-Right-Pointing-Pointer Low dose Dll4-Fc helps vascular injury recovery in skin flap model. Black-Right-Pointing-Pointer Dll4 heterozygous deletion promotes vascular injury recovery. Black-Right-Pointing-Pointer Dll4 overexpression delays vascular injury recovery. -- Abstract: Notch pathway regulates vessel development and maturation. Dll4, a high-affinity ligand for Notch, is expressed predominantly in the arterial endothelium and is induced by hypoxia among other factors. Inhibition of Dll4 has paradoxical effects of reducing the maturation and perfusion in newly forming vessels while increasing the densitymore » of vessels. We hypothesized that partial and/or intermittent inhibition of Dll4 may lead to increased vascular response and still allow vascular maturation to occur. Thus tissue perfusion can be restored rapidly, allowing quicker recovery from ischemia or tissue injury. Our studies in two different models (hindlimb ischemia and skin flap) show that inhibition of Dll4 at low dose allows faster recovery from vascular and tissue injury. This opens a new possibility for Dll4 blockade's therapeutic application in promoting recovery from vascular injury and restoring blood supply to ischemic tissues.« less

  11. The Significance of Notch1 Compared with Notch3 in High Metastasis and Poor Overall Survival in Hepatocellular Carcinoma

    PubMed Central

    Li, Qingjun; Sun, Wei; Zhang, Yong; Wang, Desheng; Dou, Kefeng

    2013-01-01

    Background The prognosis for patients with hepatocellular carcinoma (HCC) is poor, and the mechanisms underlying the development of HCC remain unclear. Notch1 and Notch3 may be involved in malignant transformation, although their roles remain unknown. Materials and Methods HCC tissues were stained with anti-Notch1 or -Notch3 antibody. The migration and invasion capacities of the cells were measured with transwell cell culture chambers. RT-PCR was used to measure the expression of Notch1 and Notch3 mRNA. Additionally, western blot analysis was used to assess the protein expression of Notch1, Notch3, CD44v6, E-cadherin, matrix metalloproteinase-2 (MMP-2), MMP-9, and urokinase-type plasminogen activator (uPA). RNA interference was used to down-regulate the expression of Notch1 and Notch3. Cell viability was assessed using MTT. Results Based on immunohistochemistry, high Notch1 expression was correlated with tumor size, tumor grade, metastasis, venous invasion and AJCC TNM stage. High Notch3 expression was only strongly correlated with metastasis, venous invasion and satellite lesions. Kaplan-Meier curves demonstrated that patients with high Notch1 or Notch3 expression were at a significantly increased risk for shortened survival time. In vitro, the down-regulation of Notch1 decreased the migration and invasion capacities of HCC cells by regulating CD44v6, E-cadherin, MMP-2, MMP-9, and uPA via the COX-2 and ERK1/2 pathways. Down-regulation of Notch3 only decreased the invasion capacity of HCC cells by regulating MMP-2 and MMP-9 via the ERK1/2 pathway. Conclusions Based on the migration and invasion of HCC, we hypothesize that targeting Notch1 may be more useful than Notch3 for designing novel preventive and therapeutic strategies for HCC in the near future. PMID:23468978

  12. Enhancing inhibition-induced plasticity in tinnitus--spectral energy contrasts in tailor-made notched music matter.

    PubMed

    Stein, Alwina; Engell, Alva; Lau, Pia; Wunderlich, Robert; Junghoefer, Markus; Wollbrink, Andreas; Bruchmann, Maximilian; Rudack, Claudia; Pantev, Christo

    2015-01-01

    Chronic tinnitus seems to be caused by reduced inhibition among frequency selective neurons in the auditory cortex. One possibility to reduce tinnitus perception is to induce inhibition onto over-activated neurons representing the tinnitus frequency via tailor-made notched music (TMNM). Since lateral inhibition is modifiable by spectral energy contrasts, the question arises if the effects of inhibition-induced plasticity can be enhanced by introducing increased spectral energy contrasts (ISEC) in TMNM. Eighteen participants suffering from chronic tonal tinnitus, pseudo randomly assigned to either a classical TMNM or an ISEC-TMNM group, listened to notched music for three hours on three consecutive days. The music was filtered for both groups by introducing a notch filter centered at the individual tinnitus frequency. For the ISEC-TMNM group a frequency bandwidth of 3/8 octaves on each side of the notch was amplified, additionally, by about 20 dB. Before and after each music exposure, participants rated their subjectively perceived tinnitus loudness on a visual analog scale. During the magnetoencephalographic recordings, participants were stimulated with either a reference tone of 500 Hz or a test tone with a carrier frequency representing the individual tinnitus pitch. Perceived tinnitus loudness was significantly reduced after TMNM exposure, though TMNM type did not influence the loudness ratings. Tinnitus related neural activity in the N1m time window and in the so called tinnitus network comprising temporal, parietal and frontal regions was reduced after TMNM exposure. The ISEC-TMNM group revealed even enhanced inhibition-induced plasticity in a temporal and a frontal cortical area. Overall, inhibition of tinnitus related neural activity could be strengthened in people affected with tinnitus by increasing spectral energy contrast in TMNM, confirming the concepts of inhibition-induced plasticity via TMNM and spectral energy contrasts.

  13. Enhancing Inhibition-Induced Plasticity in Tinnitus – Spectral Energy Contrasts in Tailor-Made Notched Music Matter

    PubMed Central

    Stein, Alwina; Engell, Alva; Lau, Pia; Wunderlich, Robert; Junghoefer, Markus; Wollbrink, Andreas; Bruchmann, Maximilian; Rudack, Claudia; Pantev, Christo

    2015-01-01

    Chronic tinnitus seems to be caused by reduced inhibition among frequency selective neurons in the auditory cortex. One possibility to reduce tinnitus perception is to induce inhibition onto over-activated neurons representing the tinnitus frequency via tailor-made notched music (TMNM). Since lateral inhibition is modifiable by spectral energy contrasts, the question arises if the effects of inhibition-induced plasticity can be enhanced by introducing increased spectral energy contrasts (ISEC) in TMNM. Eighteen participants suffering from chronic tonal tinnitus, pseudo randomly assigned to either a classical TMNM or an ISEC-TMNM group, listened to notched music for three hours on three consecutive days. The music was filtered for both groups by introducing a notch filter centered at the individual tinnitus frequency. For the ISEC-TMNM group a frequency bandwidth of 3/8 octaves on each side of the notch was amplified, additionally, by about 20 dB. Before and after each music exposure, participants rated their subjectively perceived tinnitus loudness on a visual analog scale. During the magnetoencephalographic recordings, participants were stimulated with either a reference tone of 500 Hz or a test tone with a carrier frequency representing the individual tinnitus pitch. Perceived tinnitus loudness was significantly reduced after TMNM exposure, though TMNM type did not influence the loudness ratings. Tinnitus related neural activity in the N1m time window and in the so called tinnitus network comprising temporal, parietal and frontal regions was reduced after TMNM exposure. The ISEC-TMNM group revealed even enhanced inhibition-induced plasticity in a temporal and a frontal cortical area. Overall, inhibition of tinnitus related neural activity could be strengthened in people affected with tinnitus by increasing spectral energy contrast in TMNM, confirming the concepts of inhibition-induced plasticity via TMNM and spectral energy contrasts. PMID:25951605

  14. Gamma-glutamylcyclotransferase promotes the growth of human glioma cells by activating Notch-Akt signaling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Shang-Hang; Yu, Ning; Liu, Xi-Yao

    Glioma as an aggressive type tumor is rapidly growing and has become one of the leading cause of cancer-related death worldwide. γ-Glutamylcyclotransferase (GGCT) has been shown as a diagnostic marker in various cancers. To reveal whether there is a correlation between GGCT and human glioma, GGCT expression in human glioma tissues and cell lines was first determined. We found that GGCT expression was up-regulated in human glioma tissues and cell lines. Further, we demonstrate that GGCT knockdown inhibits glioma cell T98G and U251 proliferation and colony formation, whereas GGCT overexpression leads to oppose effects. GGCT overexpression promotes the expression ofmore » Notch receptors and activates Akt signaling in glioma cells, and Notch-Akt signaling is activated in glioma tissues with high expression of GGCT. Finally, we show that inhibition of Notch-Akt signaling with Notch inhibitor MK-0752 blocks the effects of GGCT on glioma proliferation and colony formation. In conclusion, GGCT plays a critical role in glioma cell proliferation and may be a potential cancer therapeutic target. - Highlights: • GGCT expression is up-regulated in human glioma tissues and cell lines. • GGCT promotes glioma cell growth and colony formation. • GGCT promotes the activation of Notch-Akt signaling in glioma cells and tissues. • Notch inhibition blocks the role of GGCT in human glioma cells.« less

  15. Histone deacetylase 6 controls Notch3 trafficking and degradation in T-cell acute lymphoblastic leukemia cells.

    PubMed

    Pinazza, Marica; Ghisi, Margherita; Minuzzo, Sonia; Agnusdei, Valentina; Fossati, Gianluca; Ciminale, Vincenzo; Pezzè, Laura; Ciribilli, Yari; Pilotto, Giorgia; Venturoli, Carolina; Amadori, Alberto; Indraccolo, Stefano

    2018-04-12

    Several studies have revealed that endosomal sorting controls the steady-state levels of Notch at the cell surface in normal cells and prevents its inappropriate activation in the absence of ligands. However, whether this highly dynamic physiologic process can be exploited to counteract dysregulated Notch signaling in cancer cells remains unknown. T-ALL is a malignancy characterized by aberrant Notch signaling, sustained by activating mutations in Notch1 as well as overexpression of Notch3, a Notch paralog physiologically subjected to lysosome-dependent degradation in human cancer cells. Here we show that treatment with the pan-HDAC inhibitor Trichostatin A (TSA) strongly decreases Notch3 full-length protein levels in T-ALL cell lines and primary human T-ALL cells xenografted in mice without substantially reducing NOTCH3 mRNA levels. Moreover, TSA markedly reduced the levels of Notch target genes, including pTα, CR2, and DTX-1, and induced apoptosis of T-ALL cells. We further observed that Notch3 was post-translationally regulated following TSA treatment, with reduced Notch3 surface levels and increased accumulation of Notch3 protein in the lysosomal compartment. Surface Notch3 levels were rescued by inhibition of dynein with ciliobrevin D. Pharmacologic studies with HDAC1, 6, and 8-specific inhibitors disclosed that these effects were largely due to inhibition of HDAC6 in T-ALL cells. HDAC6 silencing by specific shRNA was followed by reduced Notch3 expression and increased apoptosis of T-ALL cells. Finally, HDAC6 silencing impaired leukemia outgrowth in mice, associated with reduction of Notch3 full-length protein in vivo. These results connect HDAC6 activity to regulation of total and surface Notch3 levels and suggest HDAC6 as a potential novel therapeutic target to lower Notch signaling in T-ALL and other Notch3-addicted tumors.

  16. A Novel High-Throughput 1536-well Notch1 γ-Secretase AlphaLISA Assay

    PubMed Central

    Chau, De-ming; Shum, David; Radu, Constantin; Bhinder, Bhavneet; Gin, David; Gilchrist, M. Lane; Djaballah, Hakim; Li, Yue-Ming

    2013-01-01

    The Notch pathway plays a crucial role in cell fate decisions through controlling various cellular processes. Overactive Notch signal contributes to cancer development from leukemias to solid tumors. γ-Secretase is an intramembrane protease responsible for the final proteolytic step of Notch that releases the membrane-tethered Notch fragment for signaling. Therefore, γ-secretase is an attractive drug target in treating Notch-mediated cancers. However, the absence of high-throughput γ-secretase assay using Notch substrate has limited the identification and development of γ-secretase inhibitors that specifically target the Notch signaling pathway. Here, we report on the development of a 1536-well γ-secretase assay using a biotinylated recombinant Notch1 substrate. We effectively assimilated and miniaturized this newly developed Notch1 substrate with the AlphaLISA detection technology and demonstrated its robustness with a calculated Z’ score of 0.66. We further validated this optimized assay by performing a pilot screening against a chemical library consisting of ~5,600 chemicals and identified known γ-secretase inhibitors e.g. DAPT, and Calpeptin; as well as a novel γ-secretase inhibitor referred to as KD-I-085. This assay is the first reported 1536-well AlphaLISA format and represents a novel high-throughput Notch1-γ-secretase assay, which provides an unprecedented opportunity to discover Notch-selective γ-secretase inhibitors that can be potentially used for the treatment of cancer and other human disorders. PMID:23448293

  17. Effects of 5-h multimodal stress on the molecules and pathways involved in dendritic morphology and cognitive function.

    PubMed

    Xu, Yiran; Cheng, Xiaorui; Cui, Xiuliang; Wang, Tongxing; Liu, Gang; Yang, Ruishang; Wang, Jianhui; Bo, Xiaochen; Wang, Shengqi; Zhou, Wenxia; Zhang, Yongxiang

    2015-09-01

    Stress induces cognitive impairments, which are likely related to the damaged dendritic morphology in the brain. Treatments for stress-induced impairments remain limited because the molecules and pathways underlying these impairments are unknown. Therefore, the aim of this study was to find the potential molecules and pathways related to damage of the dendritic morphology induced by stress. To do this, we detected gene expression, constructed a protein-protein interaction (PPI) network, and analyzed the molecular pathways in the brains of mice exposed to 5-h multimodal stress. The results showed that stress increased plasma corticosterone concentration, decreased cognitive function, damaged dendritic morphologies, and altered APBB1, CLSTN1, KCNA4, NOTCH3, PLAU, RPS6KA1, SYP, TGFB1, KCNA1, NTRK3, and SNCA expression in the brains of mice. Further analyses found that the abnormal expressions of CLSTN1, PLAU, NOTCH3, and TGFB1 induced by stress were related to alterations in the dendritic morphology. These four genes demonstrated interactions with 55 other genes, and configured a closed PPI network. Molecular pathway analysis use the Database for Annotation, Visualization, and Integrated Discovery (DAVID), specifically the gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG), each identified three pathways that were significantly enriched in the gene list of the PPI network, with genes belonging to the Notch and transforming growth factor-beta (TGF-B) signaling pathways being the most enriched. Our results suggest that TGFB1, PLAU, NOTCH3, and CLSTN1 may be related to the alterations in dendritic morphology induced by stress, and imply that the Notch and TGF-B signaling pathways may be involved. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Physiological Notch Signaling Maintains Bone Homeostasis via RBPjk and Hey Upstream of NFATc1

    PubMed Central

    Tu, Xiaolin; Chen, Jianquan; Lim, Joohyun; Karner, Courtney M.; Lee, Seung-Yon; Heisig, Julia; Wiese, Cornelia; Surendran, Kameswaran; Kopan, Raphael; Gessler, Manfred; Long, Fanxin

    2012-01-01

    Notch signaling between neighboring cells controls many cell fate decisions in metazoans both during embryogenesis and in postnatal life. Previously, we uncovered a critical role for physiological Notch signaling in suppressing osteoblast differentiation in vivo. However, the contribution of individual Notch receptors and the downstream signaling mechanism have not been elucidated. Here we report that removal of Notch2, but not Notch1, from the embryonic limb mesenchyme markedly increased trabecular bone mass in adolescent mice. Deletion of the transcription factor RBPjk, a mediator of all canonical Notch signaling, in the mesenchymal progenitors but not the more mature osteoblast-lineage cells, caused a dramatic high-bone-mass phenotype characterized by increased osteoblast numbers, diminished bone marrow mesenchymal progenitor pool, and rapid age-dependent bone loss. Moreover, mice deficient in Hey1 and HeyL, two target genes of Notch-RBPjk signaling, exhibited high bone mass. Interestingly, Hey1 bound to and suppressed the NFATc1 promoter, and RBPjk deletion increased NFATc1 expression in bone. Finally, pharmacological inhibition of NFAT alleviated the high-bone-mass phenotype caused by RBPjk deletion. Thus, Notch-RBPjk signaling functions in part through Hey1-mediated inhibition of NFATc1 to suppress osteoblastogenesis, contributing to bone homeostasis in vivo. PMID:22457635

  19. ERK inhibition enhances TSA-induced gastric cancer cell apoptosis via NF-κB-dependent and Notch-independent mechanism.

    PubMed

    Yao, Jun; Qian, Cui-Juan; Ye, Bei; Zhang, Xin; Liang, Yong

    2012-09-04

    To analyze the combined impact of the histone deacetylase inhibitor (HDACI) Trichostatin A (TSA) and the extracellular-signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 on gastric cancer (GC) cell line SGC7901 growth. SGC7901 cells were treated with TSA, PD98059 or with a TSA-PD98059 combination. Effects of drug treatment on tumor cell proliferation, apoptosis, cell cycle progression, and cell signaling pathways were investigated by MTS assay, flow cytometry, Western blotting, chromatin immunoprecipitation (ChIP) assay, electrophoretic mobility shift assay (EMSA), and luciferase reporter assay, respectively. PD98059 enhanced TSA-induced cell growth arrest, apoptosis and activation of p21(WAF1/CIP1), but reversed TSA-induced activation of ERK1/2 and nuclear factor-κB (NF-κB). TSA alone up-regulated Notch1 and Hes1, and down-regulated Notch2, but PD98059 did not affect the trends of Notch1 and Notch2 induced by TSA. Particularly, PD98059 did potentiate the ability of TSA to down-regulate phospho-histone H3 protein, but increased levels of the acetylated forms of histone H3 bound to the p21(WAF1/CIP1) promoter, leading to enhanced expression of p21(WAF1/CIP1) in SGC7901 cells. PD98059 synergistically potentiates TSA-induced GC growth arrest and apoptosis by manipulating NF-κB and p21(WAF1/CIP1) independent of Notch. Therefore, concomitant administration of HDACIs and ERK1/2 inhibitors may be a promising treatment strategy for individuals with GC. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Transient blockade of Delta-like Notch ligands prevents allograft rejection mediated by cellular and humoral mechanisms in a mouse model of heart transplantation

    PubMed Central

    Wood, Sherri; Feng, Jiane; Chung, Jooho; Radojcic, Vedran; Sandy, Ashley R.; Friedman, Ann; Shelton, Amy; Yan, Minhong; Siebel, Christian W.; Bishop, D. Keith; Maillard, Ivan

    2015-01-01

    Rejection remains a major clinical challenge limiting allograft survival after solid organ transplantation. Both cellular and humoral immunity contribute to this complication, with increased recognition of antibody-mediated damage during acute and chronic rejection. Using a mouse model of MHC-mismatched heart transplantation, we report markedly protective effects of Notch inhibition, dampening both T cell and antibody-driven rejection. T cell-specific pan-Notch blockade prolonged heart allograft survival and decreased IFNγ and IL-4 production by alloreactive T cells, especially when combined with depletion of recipient CD8+ T cells. These effects were associated with decreased infiltration by conventional T cells and an increased proportion of regulatory T cells in the graft. Transient administration of neutralizing antibodies specific for Delta-like1/4 (Dll1/4) Notch ligands in the peri-transplant period led to prolonged acceptance of allogeneic hearts, with superior outcome over Notch inhibition only in T cells. Systemic Dll1/4 inhibition decreased T cell cytokines and graft infiltration, but also germinal center B cell and plasmablast numbers as well as production of donor-specific alloantibodies and complement deposition in the transplanted hearts. Dll1 or Dll4 inhibition alone provided partial protection. Thus, pathogenic signals delivered by Dll1/4 Notch ligands early after transplantation promote organ rejection through several complementary mechanisms. Transient interruption of theses signals represents a new attractive therapeutic strategy to enhance long-term allograft survival. PMID:25687759

  1. RBP-J-interacting and tubulin-associated protein induces apoptosis and cell cycle arrest in human hepatocellular carcinoma by activating the p53–Fbxw7 pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Haihe; Yang, Zhanchun; Liu, Chunbo

    2014-11-07

    Highlights: • RITA overexpression increased protein expression of p53 and Fbxw7 and downregulated the expression of cyclin D1, cyclin E, CDK2, Hes-1 and NF-κB p65. • RITA can significantly inhibit the in vitro growth of SMMC7721 and HepG2 cells. • RITA exerts tumor-suppressive effects in hepatocarcinogenesis through induction of G0/G1 cell cycle arrest and apoptosis and suggest a therapeutic application of RITA in HCC. - Abstract: Aberrant Notch signaling is observed in human hepatocellular carcinoma (HCC) and has been associated with the modulation of cell growth. However, the role of Notch signaling in HCC and its underlying mechanism remain elusive.more » RBP-J-interacting and tubulin-associated (RITA) mediates the nuclear export of RBP-J to tubulin fibers and downregulates Notch-mediated transcription. In this study, we found that RITA overexpression increased protein expression of p53 and Fbxw7 and downregulated the expression of cyclin D1, cyclin E, CDK2, Hes-1 and NF-κB p65. These changes led to growth inhibition and induced G0/G1 cell cycle arrest and apoptosis in SMMC7721 and HepG2 cells. Our findings indicate that RITA exerts tumor-suppressive effects in hepatocarcinogenesis through induction of G0/G1 cell cycle arrest and apoptosis and suggest a therapeutic application of RITA in HCC.« less

  2. Notch3 drives development and progression of cholangiocarcinoma

    PubMed Central

    Guest, Rachel V.; Dwyer, Benjamin J.; Kendall, Timothy J.; Man, Tak-Yung; Minnis-Lyons, Sarah E.; Lu, Wei-Yu; Robson, Andrew J.; Gonzalez, Sofia Ferreira; Raven, Alexander; Wojtacha, Davina; Morton, Jennifer P.; Komuta, Mina; Roskams, Tania; Wigmore, Stephen J.; Sansom, Owen J.; Forbes, Stuart J.

    2016-01-01

    The prognosis of cholangiocarcinoma (CC) is dismal. Notch has been identified as a potential driver; forced exogenous overexpression of Notch1 in hepatocytes results in the formation of biliary tumors. In human disease, however, it is unknown which components of the endogenously signaling pathway are required for tumorigenesis, how these orchestrate cancer, and how they can be targeted for therapy. Here we characterize Notch in human-resected CC, a toxin-driven model in rats, and a transgenic mouse model in which p53 deletion is targeted to biliary epithelia and CC induced using the hepatocarcinogen thioacetamide. We find that across species, the atypical receptor NOTCH3 is differentially overexpressed; it is progressively up-regulated with disease development and promotes tumor cell survival via activation of PI3k-Akt. We use genetic KO studies to show that tumor growth significantly attenuates after Notch3 deletion and demonstrate signaling occurs via a noncanonical pathway independent of the mediator of classical Notch, Recombinant Signal Binding Protein for Immunoglobulin Kappa J Region (RBPJ). These data present an opportunity in this aggressive cancer to selectively target Notch, bypassing toxicities known to be RBPJ dependent. PMID:27791012

  3. Autophagy contributes to 4-Amino-2-Trifluoromethyl-Phenyl Retinate-induced differentiation in human acute promyelocytic leukemia NB4 cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Yue; Li, Ge; Wang, Ke

    As a classic differentiation agent, all-trans retinoic acid (ATRA) has been widely used in treatment of acute promyelocytic leukemia (APL). However, clinical application of ATRA has limitations. Our previous studies suggested that 4-Amino-2-Trifluoromethyl-Phenyl Retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative designed and synthesized by our team, could induce differentiation of APL cells in vivo and in vitro. To explore the underlying mechanism of ATPR, the effect of ATPR on autophagy of APL cells was observed in the present study. The results showed that the differentiation effect of ATPR on APL cells was accompanied with autophagy induction and PML-RARαmore » degradation via activating Notch1 signaling pathway. Moreover, inhibition of autophagy using 3-methyladenine (3-MA) or small interfering RNA (siRNA) that targets essential autophagy gene ATG5 abrogated the ATPR-induced cell differentiation. Furthermore, when pretreated with DAPT, a γ-secretase inhibitor, the Notch1 signaling pathway was blocked in APL cells, followed by the reduction of ATPR-induced autophagy and differentiation. Taken together, these results suggested that autophagy play an important role in ATPR-induced cell differentiation, which may provide a novel approach to cure APL patients. - Highlights: • ATPR induces autophagy in APL cell line NB4 cells. • Autophagy induction is essential for cell differentiation in NB4 cells. • Notch1 signaling is involved in ATPR-induced autophagy and differentiation in NB4 cells.« less

  4. RITA, a novel modulator of Notch signalling, acts via nuclear export of RBP-J.

    PubMed

    Wacker, Stephan Armin; Alvarado, Cristobal; von Wichert, Götz; Knippschild, Uwe; Wiedenmann, Jörg; Clauss, Karen; Nienhaus, Gerd Ulrich; Hameister, Horst; Baumann, Bernd; Borggrefe, Tilman; Knöchel, Walter; Oswald, Franz

    2011-01-05

    The evolutionarily conserved Notch signal transduction pathway regulates fundamental cellular processes during embryonic development and in the adult. Ligand binding induces presenilin-dependent cleavage of the receptor and a subsequent nuclear translocation of the Notch intracellular domain (NICD). In the nucleus, NICD binds to the recombination signal sequence-binding protein J (RBP-J)/CBF-1 transcription factor to induce expression of Notch target genes. Here, we report the identification and functional characterization of RBP-J interacting and tubulin associated (RITA) (C12ORF52) as a novel RBP-J/CBF-1-interacting protein. RITA is a highly conserved 36 kDa protein that, most interestingly, binds to tubulin in the cytoplasm and shuttles rapidly between cytoplasm and nucleus. This shuttling RITA exports RBP-J/CBF-1 from the nucleus. Functionally, we show that RITA can reverse a Notch-induced loss of primary neurogenesis in Xenopus laevis. Furthermore, RITA is able to downregulate Notch-mediated transcription. Thus, we propose that RITA acts as a negative modulator of the Notch signalling pathway, controlling the level of nuclear RBP-J/CBF-1, where its amounts are limiting.

  5. Developmental expression of the Notch signaling pathway genes during mouse preimplantation development.

    PubMed

    Cormier, Sarah; Vandormael-Pournin, Sandrine; Babinet, Charles; Cohen-Tannoudji, Michel

    2004-10-01

    Notch signaling is an evolutionary conserved pathway involved in intercellular signaling and essential for proper cell fate choices during development. Thus, it could be involved in mouse preimplantation development where intercellular signaling plays a crucial role, particularly between the inner cell mass and the trophectoderm of the blastocyst. At their face value, the phenotypes observed when disrupting each of the four Notch genes known in the mouse do not support this view as none of them involves perturbation of preimplantation development. However this could be due to functional redundancy and/or maternal expression. As a first step to address this issue, we decided to examine the expression in early development of various genes known to participate in Notch signaling. Here, we report on the expression pattern of Notch1-4, Jagged1 (Jag1), Jag2, Delta-like1 (Dll-1), Dll-3, Dll-4, Rbpsuh, Deltex1(Dtx1)and Dtx2 genes during preimplantation development from unfertilized eggs until late blastocyst stage using a RT-PCR strategy. We show that Notch1, 2, Jag1-2, Dll-3, Rbpsuh and Dtx2 transcripts are expressed at all stages. Notch4 and Dll-4 mRNAs are synthesized from the 2-cell through to the hatched blastocyst stage. Notch3, Dll-1 and Dtx1exhibit a stage dependent expression as their mRNAs are detected in 2-cell embryos and in hatched blastocysts, but are absent or weakly detected at the morula stage. Finally, we show that all the above genes are expressed both in Embryonic and Trophoblast Stem cells (ES and TS cells, respectively). Our results suggest that the Notch pathway may be active during mouse preimplantation development.

  6. C. elegans Notch signaling regulates adult chemosensory response and larval molting quiescence

    PubMed Central

    Singh, Komudi; Chao, Michael Y.; Somers, Gerard A.; Komatsu, Hidetoshi; Corkins, Mark E.; Larkins-Ford, Jonah; Tucey, Tim; Dionne, Heather M.; Walsh, Melissa B.; Beaumont, Emma K.; Hart, Douglas P.; Lockery, Shawn; Hart, Anne C.

    2011-01-01

    Summary Background The conserved DOS motif proteins OSM-7 and OSM-11 function as co-ligands with canonical DSL ligands to activate C. elegans Notch receptors during development. We report herein that Notch ligands, co-ligands and the receptors LIN-12 and GLP-1 regulate two C. elegans behaviors: chemosensory avoidance of octanol and quiescence during molting lethargus. Results C. elegans lacking osm-7 or osm-11 are defective in their response to octanol. We find that OSM-11 is secreted from hypodermal seam cells into the pseudocoelomic body cavity and acts non-cell autonomously as a diffusible factor. OSM-11 acts with the DSL ligand LAG-2 to activate LIN-12 and GLP-1 Notch receptors in the neurons of adult animals,- thereby regulating octanol avoidance response. In adult animals, over-expression of osm-11 and consequent Notch receptor activation induces anachronistic sleep-like quiescence. Perturbation of Notch signaling altered basal activity in adults as well as arousal thresholds and quiescence during molting lethargus. Genetic epistasis studies revealed that Notch signaling regulates quiescence via previously identified circuits and genetic pathways including the egl-4 cGMP-dependent kinase. Conclusions Our findings indicate that the conserved Notch pathway modulates behavior in adult C. elegans in response to environmental stress. Additionally, Notch signaling regulates sleep-like quiescence in C. elegans suggesting Notch may regulate sleep in other species. PMID:21549604

  7. Notch-1-PTEN-ERK1/2 signaling axis promotes HER2+ breast cancer cell proliferation and stem cell survival.

    PubMed

    Baker, Andrew; Wyatt, Debra; Bocchetta, Maurizio; Li, Jun; Filipovic, Aleksandra; Green, Andrew; Peiffer, Daniel S; Fuqua, Suzanne; Miele, Lucio; Albain, Kathy S; Osipo, Clodia

    2018-05-10

    Trastuzumab targets the HER2 receptor on breast cancer cells to attenuate HER2-driven tumor growth. However, resistance to trastuzumab-based therapy remains a major clinical problem for women with HER2+ breast cancer. Breast cancer stem cells (BCSCs) are suggested to be responsible for drug resistance and tumor recurrence. Notch signaling has been shown to promote BCSC survival and self-renewal. Trastuzumab-resistant cells have increased Notch-1 expression. Notch signaling drives cell proliferation in vitro and is required for tumor recurrence in vivo. We demonstrate herein a mechanism by which Notch-1 is required for trastuzumab resistance by repressing PTEN expression to contribute to activation of ERK1/2 signaling. Furthermore, Notch-1-mediated inhibition of PTEN is necessary for BCSC survival in vitro and in vivo. Inhibition of MEK1/2-ERK1/2 signaling in trastuzumab-resistant breast cancer cells mimics effects of Notch-1 knockdown on bulk cell proliferation and BCSC survival. These findings suggest that Notch-1 contributes to trastuzumab resistance by repressing PTEN and this may lead to hyperactivation of ERK1/2 signaling. Furthermore, high Notch-1 and low PTEN mRNA expression may predict poorer overall survival in women with breast cancer. Notch-1 protein expression predicts poorer survival in women with HER2+ breast cancer. These results support a potential future clinical trial combining anti-Notch-1 and anti-MEK/ERK therapy for trastuzumab-resistant breast cancer.

  8. Hypoxia-driven angiogenesis: role of tip cells and extracellular matrix scaffolding.

    PubMed

    Germain, Stéphane; Monnot, Catherine; Muller, Laurent; Eichmann, Anne

    2010-05-01

    Angiogenesis is a highly coordinated tissue remodeling process leading to blood vessel formation. Hypoxia triggers angiogenesis via induction of expression of growth factors such as vascular endothelial growth factor (VEGF). VEGF instructs endothelial cells to form tip cells, which lead outgrowing capillary sprouts, whereas Notch signaling inhibits sprout formation. Basement membrane deposition and mechanical cues from the extracellular matrix (ECM) induced by hypoxia may participate to coordinated vessel sprouting in conjunction with the VEGF and Notch signaling pathways. Hypoxia regulates ECM composition, deposition, posttranslational modifications and rearrangement. In particular, hypoxia-driven vascular remodeling is dynamically regulated through modulation of ECM-modifying enzyme activities that eventually affect both matricellular proteins and growth factor availability. Better understanding of the complex interplay between endothelial cells and soluble growth factors and mechanical factors from the ECM will certainly have significant implications for understanding the regulation of developmental and pathological angiogenesis driven by hypoxia.

  9. Identification of small molecule Hes1 modulators as potential anticancer chemotherapeutics.

    PubMed

    Sail, Vibhavari; Hadden, M Kyle

    2013-03-01

    Hes1 is a key transcriptional regulator primarily controlled by the Notch signaling pathway, and recent studies have demonstrated both an oncogenic and tumor suppressor role for Hes1, depending on the cell type. Small molecules that activate and inhibit Hes1 activity hold promise as future anticancer chemotherapeutics. We have utilized a cell-based dual luciferase assay to identify modulators of Hes1 expression in a medium-throughput format. A modest screen was performed in HCT-116 colon cancer cell lines, and two small molecules were identified and characterized as Hes1 regulators. Compound 3 induced Hes1 expression and exhibited anticancer effects in pulmonary carcinoid tumor cells, a cell type in which the upregulated Notch/Hes1 signaling plays a tumor suppressive role. Treatment of HCT-116 cells with compound 12 resulted in Hes1 downregulation and antitumor effects. © 2012 John Wiley & Sons A/S.

  10. Notch signaling pathways in human thoracic ossification of the ligamentum flavum.

    PubMed

    Qu, Xiaochen; Chen, Zhongqiang; Fan, Dongwei; Sun, Chuiguo; Zeng, Yan; Hou, Xiaofei; Ning, Shanglong

    2016-08-01

    This study investigated the pathological process of Notch signaling in the osteogenesis of ligamentum flavum tissues and cells, and the associated regulatory mechanisms. Notch receptors, ligands, and target genes were identified by quantitative polymerase chain reaction (qPCR) in ligamentum flavum cells and immunohistochemistry in ligamentum flavum sections from ossification of the ligamentum flavum (OLF) patients and controls. The temporospatial expression patterns of JAG1/Notch2/HES1 in human ligamentum flavum cells during osteogenic differentiation were determined by qPCR. Lentiviral vectors for Notch2 overexpression and knockdown were constructed and transfected into ligamentum flavum cells before osteogenic differentiation to examine the function of Notch signaling pathways in the osteogenic differentiation of ligamentum flavum cells. Alkaline phosphatase, Runx2, Osterix, osteocalcin, and osteopontin mRNA levels, alkaline phosphatase activity, and Alizarin Red staining were used as indicators of osteogenic differentiation. JAG1/Notch2/HES1 mRNA levels were up-regulated in ligamentum flavum cells from OLF patients, which increased during osteogenic differentiation. Immunohistochemical analysis suggested positive Notch2 expression at the ossification front. Down-regulation of Notch2 expression decelerated osteogenic differentiation of ligamentum flavum cells, and Notch2 overexpression promoted osteogenic differentiation of ligamentum flavum cells. Expression of Runx2 and Osterix increased in a manner similar to that of Notch2 during osteogenic differentiation of ligamentum flavum cells, and Notch2 knockdown and overexpression influenced their expression levels. Notch signaling plays an important role in OLF, and Notch may affect the osteogenic differentiation of ligamentum flavum cells via interactions with Runx2 and Osterix.© 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1481-1491, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  11. Notch Signaling Activation Is Associated with Patient Mortality and Increased FGF1-Mediated Invasion in Squamous Cell Carcinoma of the Oral Cavity.

    PubMed

    Weaver, Alice N; Burch, M Benjamin; Cooper, Tiffiny S; Della Manna, Deborah L; Wei, Shi; Ojesina, Akinyemi I; Rosenthal, Eben L; Yang, Eddy S

    2016-09-01

    Oral squamous cell carcinoma (OSCC) is a cancer subtype that lacks validated prognostic and therapeutic biomarkers, and human papillomavirus status has not proven beneficial in predicting patient outcomes. A gene expression pathway analysis was conducted using OSCC patient specimens to identify molecular targets that may improve management of this disease. RNA was isolated from 19 OSCCs treated surgically at the University of Alabama at Birmingham (UAB; Birmingham, AL) and evaluated using the NanoString nCounter system. Results were confirmed using the oral cavity subdivision of the Head and Neck Squamous Cell Carcinoma Cancer (HNSCC) study generated by The Cancer Genome Atlas (TCGA) Research Network. Further characterization of the in vitro phenotype produced by Notch pathway activation in HNSCC cell lines included gene expression, proliferation, cell cycle, migration, invasion, and radiosensitivity. In both UAB and TCGA samples, Notch pathway upregulation was significantly correlated with patient mortality status and with expression of the proinvasive gene FGF1 In vitro Notch activation in HNSCC cells increased transcription of FGF1 and induced a marked increase in cell migration and invasion, which was fully abrogated by FGF1 knockdown. These results reveal that increased Notch pathway signaling plays a role in cancer progression and patient outcomes in OSCC. Accordingly, the Notch-FGF interaction should be further studied as a prognostic biomarker and potential therapeutic target for OSCC. Patients with squamous cell carcinoma of the oral cavity who succumb to their disease are more likely to have upregulated Notch signaling, which may mediate a more invasive phenotype through increased FGF1 transcription. Mol Cancer Res; 14(9); 883-91. ©2016 AACR. ©2016 American Association for Cancer Research.

  12. Membrane receptor-dependent Notch1/Hes1 activation by melatonin protects against myocardial ischemia-reperfusion injury: in vivo and in vitro studies.

    PubMed

    Yu, Liming; Liang, Hongliang; Lu, Zhihong; Zhao, Guolong; Zhai, Mengen; Yang, Yang; Yang, Jian; Yi, Dinghua; Chen, Wensheng; Wang, Xiaowu; Duan, Weixun; Jin, Zhenxiao; Yu, Shiqiang

    2015-11-01

    Melatonin confers profound protective effect against myocardial ischemia-reperfusion injury (MI/RI). Activation of Notch1/Hairy and enhancer of split 1 (Hes1) signaling also ameliorates MI/RI. We hypothesize that melatonin attenuates MI/RI-induced oxidative damage by activating Notch1/Hes1 signaling pathway with phosphatase and tensin homolog deleted on chromosome 10 (Pten)/Akt acting as the downstream signaling pathway in a melatonin membrane receptor-dependent manner. Male Sprague Dawley rats were treated with melatonin (10 mg/kg/day) for 4 wk and then subjected to MI/R surgery. Melatonin significantly improved cardiac function and decreased myocardial apoptosis and oxidative damage. Furthermore, in cultured H9C2 cardiomyocytes, melatonin (100 μmol/L) attenuated simulated ischemia-reperfusion (SIR)-induced myocardial apoptosis and oxidative damage. Both in vivo and in vitro study demonstrated that melatonin treatment increased Notch1, Notch1 intracellular domain (NICD), Hes1, Bcl-2 expressions, and p-Akt/Akt ratio and decreased Pten, Bax, and caspase-3 expressions. However, these protective effects conferred by melatonin were blocked by DAPT (the specific inhibitor of Notch1 signaling), luzindole (the antagonist of melatonin membrane receptors), Notch1 siRNA, or Hes1 siRNA administration. In summary, our study demonstrates that melatonin treatment protects against MI/RI by modulating Notch1/Hes1 signaling in a receptor-dependent manner and Pten/Akt signaling pathways are key downstream mediators. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Traffic jam functions in a branched pathway from Notch activation to niche cell fate.

    PubMed

    Wingert, Lindsey; DiNardo, Stephen

    2015-07-01

    The niche directs key behaviors of its resident stem cells, and is thus crucial for tissue maintenance, repair and longevity. However, little is known about the genetic pathways that guide niche specification and development. The male germline stem cell niche in Drosophila houses two stem cell populations and is specified within the embryonic gonad, thus making it an excellent model for studying niche development. The hub cells that form the niche are specified early by Notch activation. Over the next few hours, these individual cells then cluster together and take up a defined position before expressing markers of hub cell differentiation. This timing suggests that there are other factors for niche development yet to be defined. Here, we have identified a role for the large Maf transcription factor Traffic jam (Tj) in hub cell specification downstream of Notch. Tj downregulation is the first detectable effect of Notch activation in hub cells. Furthermore, Tj depletion is sufficient to generate ectopic hub cells that can recruit stem cells. Surprisingly, ectopic niche cells in tj mutants remain dispersed in the absence of Notch activation. This led us to uncover a branched pathway downstream of Notch in which Bowl functions to direct hub cell assembly in parallel to Tj downregulation. © 2015. Published by The Company of Biologists Ltd.

  14. Epidermal stem cells (ESCs) accelerate diabetic wound healing via the Notch signalling pathway.

    PubMed

    Yang, Rong-Hua; Qi, Shao-Hai; Shu, Bin; Ruan, Shu-Bin; Lin, Ze-Peng; Lin, Yan; Shen, Rui; Zhang, Feng-Gang; Chen, Xiao-Dong; Xie, Ju-Lin

    2016-08-01

    Chronic, non-healing wounds are a major complication of diabetes. Recently, various cell therapies have been reported for promotion of diabetic wound healing. Epidermal stem cells (ESCs) are considered a powerful tool for tissue therapy. However, the effect and the mechanism of the therapeutic properties of ESCs in the diabetic wound healing are unclear. Herein, to determine the ability of ESCs to diabetic wound healing, a dorsal skin defect in a streptozotocin (STZ)-induced diabetes mellitus (DM) mouse model was used. ESCs were isolated from mouse skin. We found that both the mRNA and protein levels of a Notch ligand Jagged1 (Jag1), Notch1 and Notch target gene Hairy Enhancer of Split-1 (Hes1) were significantly increased at the wound margins. In addition, we observed that Jag1 was high expressed in ESCs. Overexpression of Jag1 promotes ESCs migration, whereas knockdown Jag1 resulted in a significant reduction in ESCs migration in vitro Importantly, Jag1 overexpression improves diabetic wound healing in vivo These results provide evidence that ESCs accelerate diabetic wound healing via the Notch signalling pathway, and provide a promising potential for activation of the Notch pathway for the treatment of diabetic wound. © 2016 The Author(s).

  15. Luteolin suppresses angiogenesis and vasculogenic mimicry formation through inhibiting Notch1-VEGF signaling in gastric cancer.

    PubMed

    Zang, Mingde; Hu, Lei; Zhang, Baogui; Zhu, Zhenglun; Li, Jianfang; Zhu, Zhenggang; Yan, Min; Liu, Bingya

    2017-08-26

    Gastric cancer is a great threat to the health of the people worldwide and lacks effective therapeutic regimens. Luteolin is one of Chinese herbs and presents in many fruits and green plants. In our previous study, we observed that luteolin inhibited cell migration and promoted cell apoptosis in gastric cancer. In the present study, luteolin significantly inhibited tube formation of human umbilical vein endothelial cells (HUVECs) through decreasing cell migration and proliferation of HUVECs in a dose-dependent manner. Vasculogenic mimicry (VM) tubes formed by gastric cancer cells were also inhibited with luteolin treatment. To explore how luteolin inhibited tubes formation, ELISA assay for VEGF was performed. Both of the VEGF secretion from Hs-746T cells and HUVECs were significantly decreased subsequent to luteolin treatment. In addition, cell migration was increased with the interaction between gastric cancer cells and HUVECs in co-culture assays. However, the promoting effects were abolished subsequent to luteolin treatment. Furthermore, luteolin inhibited VEGF secretion through suppressing Notch1 expression in gastric cancer. Overexpression of Notch1 in gastric cancer cells partially rescued the effects on cell migration, proliferation, HUVECs tube formation, and VM formation induced by luteolin treatment. In conclusion, luteolin inhibits angiogenesis and VM formation in gastric cancer through suppressing VEGF secretion dependent on Notch1 expression. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. A Jagged 1-Notch 4 molecular switch mediates airway inflammation induced by ultrafine particles.

    PubMed

    Xia, Mingcan; Harb, Hani; Saffari, Arian; Sioutas, Constantinos; Chatila, Talal A

    2018-04-05

    Exposure to traffic-related particulate matter promotes asthma and allergic diseases. However, the precise cellular and molecular mechanisms by which particulate matter exposure acts to mediate these effects remain unclear. We sought to elucidate the cellular targets and signaling pathways critical for augmentation of allergic airway inflammation induced by ambient ultrafine particles (UFP). We used in vitro cell-culture assays with lung-derived antigen-presenting cells and allergen-specific T cells and in vivo mouse models of allergic airway inflammation with myeloid lineage-specific gene deletions, cellular reconstitution approaches, and antibody inhibition studies. We identified lung alveolar macrophages (AM) as the key cellular target of UFP in promoting airway inflammation. Aryl hydrocarbon receptor-dependent induction of Jagged 1 (Jag1) expression in AM was necessary and sufficient for augmentation of allergic airway inflammation by UFP. UFP promoted T H 2 and T H 17 cell differentiation of allergen-specific T cells in a Jag1- and Notch 4-dependent manner. Treatment of mice with an anti-Notch 4 antibody abrogated exacerbation of allergic airway inflammation induced by UFP. UFP exacerbate allergic airway inflammation by promoting a Jag1-Notch 4-dependent interaction between AM and allergen-specific T cells, leading to augmented T H cell differentiation. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  17. Upregulation of miR-181a suppresses the formation of glioblastoma stem cells by targeting the Notch2 oncogene and correlates with good prognosis in patients with glioblastoma multiforme

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Shi-Xiong; Zhao, Zhong-Yan; Weng, Guo-Hu

    Glioblastoma stem-like cells (GSCs) are responsible for the initiation and progression of glioblastoma multiforme (GBM), and microRNAs (miRNAs) play an important role in this disease. However, the mechanisms underlying the role of miRNAs in the stemness of GSCs have not been completely elucidated. We previously showed that miR-181a is downregulated in GBM and may predict prognosis in patients with this disease. Here, we demonstrate that the upregulation of miR-181a suppressed GSC formation and inhibited GBM tumorigenesis by targeting the Notch2 oncogene. We found that miR-181a was downregulated in GSCs derived from human glioblastoma U87MG and U373MG cells. The high expressionmore » of miR-181a inhibited the levels of stemness-related markers CD133 and BMI1, attenuated sphere proliferation, promoted cell apoptosis, and reduced the tumorigenicity of GSCs. MiR-181a decreased the expression of Notch2 by targeting the 3’-untranslated region of its mRNA. Notch2 overexpression inhibited the effects of miR-181a downregulation on GSCs, and was negatively correlated with miR-181a expression. Moreover, high Notch2 expression together with low miR-181a expression was correlated with a shorter median overall survival for GBM patients. Together, these data show that miR-181a may play an essential role in GSC formation and GBM progression by targeting Notch2, suggesting that Notch2 and miR-181a have potential prognostic value as tumor biomarkers in GBM patients. - Highlights: • MiR-181a suppressed GSC formation and GBM tumorigenesis by targeting Notch2. • Notch2 and miR-181a expression were correlated with OS for GBM patients. • Notch2 and miR-181a have potential prognostic value in GBM patients.« less

  18. Yap1 as a New Therapeutic Target in Neurofibromatosis Type 2

    DTIC Science & Technology

    2013-09-01

    Hedgehog and Notch has particularly contributed to the understanding and treatment of cancer1. A more recently discovered signalling cascade is the...Wnt, Notch, and Hedgehog pathways. Nat. Rev. Clin. Oncol. 8, 97–106 (2011). 2. Zhao, B., Lei, Q. Y. & Guan, K. L. The Hippo-YAP pathway: new

  19. An alternative way to initiate Notch1 signaling in non-small cell lung cancer

    PubMed Central

    Yang, Yi-Lin; Jablons, David

    2014-01-01

    Non-small cell lung cancer (NSCLC) cells activate Notch1 signaling to promote cell proliferation and facilitate their survival. It now emerges that endothelial Delta-like ligand 4 (Dll4) may mediate Notch1 activation and inhibit tumor cell growth. PMID:25806306

  20. NADPH Oxidase 1 Modulates WNT and NOTCH1 Signaling To Control the Fate of Proliferative Progenitor Cells in the Colon▿

    PubMed Central

    Coant, Nicolas; Ben Mkaddem, Sanae; Pedruzzi, Eric; Guichard, Cécile; Tréton, Xavier; Ducroc, Robert; Freund, Jean-Noel; Cazals-Hatem, Dominique; Bouhnik, Yoram; Woerther, Paul-Louis; Skurnik, David; Grodet, Alain; Fay, Michèle; Biard, Denis; Lesuffleur, Thécla; Deffert, Christine; Moreau, Richard; Groyer, André; Krause, Karl-Heinz; Daniel, Fanny; Ogier-Denis, Eric

    2010-01-01

    The homeostatic self-renewal of the colonic epithelium requires coordinated regulation of the canonical Wnt/β-catenin and Notch signaling pathways to control proliferation and lineage commitment of multipotent stem cells. However, the molecular mechanisms by which the Wnt/β-catenin and Notch1 pathways interplay in controlling cell proliferation and fate in the colon are poorly understood. Here we show that NADPH oxidase 1 (NOX1), a reactive oxygen species (ROS)-producing oxidase that is highly expressed in colonic epithelial cells, is a pivotal determinant of cell proliferation and fate that integrates Wnt/β-catenin and Notch1 signals. NOX1-deficient mice reveal a massive conversion of progenitor cells into postmitotic goblet cells at the cost of colonocytes due to the concerted repression of phosphatidylinositol 3-kinase (PI3K)/AKT/Wnt/β-catenin and Notch1 signaling. This conversion correlates with the following: (i) the redox-dependent activation of the dual phosphatase PTEN, causing the inactivation of the Wnt pathway effector β-catenin, and (ii) the downregulation of Notch1 signaling that provokes derepression of mouse atonal homolog 1 (Math1) expression. We conclude that NOX1 controls the balance between goblet and absorptive cell types in the colon by coordinately modulating PI3K/AKT/Wnt/β-catenin and Notch1 signaling. This finding provides the molecular basis for the role of NOX1 in cell proliferation and postmitotic differentiation. PMID:20351171

  1. Inhibition of myostatin signaling through Notch activation following acute resistance exercise.

    PubMed

    MacKenzie, Matthew G; Hamilton, David Lee; Pepin, Mark; Patton, Amy; Baar, Keith

    2013-01-01

    Myostatin is a TGFβ family member and negative regulator of muscle size. Due to the complexity of the molecular pathway between myostatin mRNA/protein and changes in transcription, it has been difficult to understand whether myostatin plays a role in resistance exercise-induced skeletal muscle hypertrophy. To circumvent this problem, we determined the expression of a unique myostatin target gene, Mighty, following resistance exercise. Mighty mRNA increased by 6 h (82.9 ± 24.21%) and remained high out to 48 h (56.5 ± 19.67%) after resistance exercise. Further examination of the soleus, plantaris and tibialis anterior muscles showed that the change in Mighty mRNA at 6 h correlated with the increase in muscle size associated with this protocol (R(2) = 0.9996). The increase in Mighty mRNA occurred both independent of Smad2 phosphorylation and in spite of an increase in myostatin mRNA (341.8 ± 147.14% at 3 h). The myostatin inhibitor SKI remained unchanged. However, activated Notch, another potential inhibitor of TGFβ signaling, increased immediately following resistance exercise (83 ± 11.2%) and stayed elevated out to 6 h (78 ± 16.6%). Electroportion of the Notch intracellular domain into the tibialis anterior resulted in an increase in Mighty mRNA (63 ± 13.4%) that was equivalent to the canonical Notch target HES-1 (94.4 ± 7.32%). These data suggest that acute resistance exercise decreases myostatin signaling through the activation of the TGFβ inhibitor Notch resulting in a decrease in myostatin transcriptional activity that correlates well with muscle hypertrophy.

  2. [Expression of Jagged1 mRNA in human epithelial ovarian carcinoma tissues and effect of RNA interference of Jagged1 on growth of xenograft in nude mice].

    PubMed

    Liu, G Y; Gao, Z H; Li, L; Song, T T; Sheng, X G

    2016-06-25

    To investigate the expression of Jagged1 in human epithelial ovarian carcinoma tissues and the effect of Jagged1 on growth of xenograft in nude mice. (1) Forty-eight cases of ovarian cancer and 30 cases of patients with benign epithelial ovarian tumor in the Henan Province Xinxiang Central Hospital during Feb. 2011 to Mar. 2014 were enrolled in this study. The mRNA expression of Jagged1, Notch1 and the downstream target genes Hes1, Hey1 were analyzed by using realtime PCR method. (2) The ovarian cancer xenograft models in nude mice were constructed by injecting SKOV3 cells in axillary subcutaneouswere. The nude mice were randomly divided into Jagged1 interference group, blank plasmid group and control group. Each group had 10 mice. They were transfected with pcDNA3.1(+)-siRNA-Jagged1, blank plasmid pDC3.1 and phosphate buffer, respectively. The tumor volumes and tumor masses were measured 14 days after transfection and the inhibition rate was calculated. The relative mRNA expression of Jagged1, Notch1, Hes1 and Hey1 in xenograft tissues after transfection in each group was detected by using realtime PCR technique and the relative protein expression of Jagged1, Notch1, Hes1 and Hey1 in xenograft tissues was detected by utilizing western blot method. (1) The relative mRNA expression of Jagged1, Notch1, Hes1 and Hey1 in ovarian cancer tissues were higher than benign ovarian tumor tissues, the differences were statistically significant (P<0.01). (2) The tumor volume was (491± 68) mm(3) and tumor mass was (2.6±0.4) g in Jagged1 interference group, which were significantly lower than that in the blank plasmid group [(842±88) mm(3) and (4.4±0.8) g, respectively] and that in the control group [(851±90) mm(3) and (4.5±0.9) g, respectively; P<0.05], the tumor inhibition rate was 42.2% in Jagged1 interference group, which was significantly higher than that in the blank plasmid group and that in the control group (2.2% and 0, respectively), the differences were statistically significant (P<0.05). The relative mRNA and protein expression of Jagged1, Hes1 and Hey1 in xenograft tissues of nude micein Jagged1 interference group were lower than that in the other two groups, the differences were statistically significant (P<0.05). There were no differences of relative mRNA and protein expression of Notch1 in xenograft tissues of nude mice among the three groups (P>0.05). Jagged1 is highly expressed in epithelial ovarian carcinoma. Jagged1 gene interference in xenograft tumor can inhibit ovarian cancer cell growth and improve tumor suppressor rate, which probably play roles by inhibiting Notch1 signaling pathway.

  3. Biochemical Characterization and Cellular Effects of CADASIL Mutants of NOTCH3

    PubMed Central

    Meng, He; Zhang, Xiaojie; Yu, Genggeng; Lee, Soo Jung; Chen, Y. Eugene; Prudovsky, Igor; Wang, Michael M.

    2012-01-01

    Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is the best understood cause of dominantly inherited stroke and results from NOTCH3 mutations that lead to NOTCH3 protein accumulation and selective arterial smooth muscle degeneration. Previous studies show that NOTCH3 protein forms multimers. Here, we investigate protein interactions between NOTCH3 and other vascular Notch isoforms and characterize the effects of elevated NOTCH3 on smooth muscle gene regulation. We demonstrate that NOTCH3 forms heterodimers with NOTCH1, NOTCH3, and NOTCH4. R90C and C49Y mutant NOTCH3 form complexes which are more resistant to detergents than wild type NOTCH3 complexes. Using quantitative NOTCH3-luciferase clearance assays, we found significant inhibition of mutant NOTCH3 clearance. In coculture assays of NOTCH function, overexpressed wild type and mutant NOTCH3 significantly repressed NOTCH-regulated smooth muscle transcripts and potently impaired the activity of three independent smooth muscle promoters. Wildtype and R90C recombinant NOTCH3 proteins applied to cell cultures also blocked canonical Notch fuction. We conclude that CADASIL mutants of NOTCH3 complex with NOTCH1, 3, and 4, slow NOTCH3 clearance, and that overexpressed wild type and mutant NOTCH3 protein interfere with key NOTCH-mediated functions in smooth muscle cells. PMID:23028706

  4. Notch-1 Signalling Is Activated in Brain Arteriovenous Malformations in Humans

    ERIC Educational Resources Information Center

    ZhuGe, Qichuan; Zhong, Ming; Zheng, WeiMing; Yang, Guo-Yuan; Mao, XiaoOu; Xie, Lin; Chen, Gourong; Chen, Yongmei; Lawton, Michael T.; Young, William L.; Greenberg, David A.; Jin, Kunlin

    2009-01-01

    A role for the Notch signalling pathway in the formation of arteriovenous malformations during development has been suggested. However, whether Notch signalling is involved in brain arteriovenous malformations in humans remains unclear. Here, we performed immunohistochemistry on surgically resected brain arteriovenous malformations and found that,…

  5. Aberrant Notch1-dependent effects on glomerular parietal epithelial cells promotes collapsing focal segmental glomerulosclerosis with progressive podocyte loss.

    PubMed

    Ueno, Toshiharu; Kobayashi, Namiko; Nakayama, Makiko; Takashima, Yasutoshi; Ohse, Takamoto; Pastan, Ira; Pippin, Jeffrey W; Shankland, Stuart J; Uesugi, Noriko; Matsusaka, Taiji; Nagata, Michio

    2013-06-01

    Collapsing focal segmental glomerulosclerosis (cFSGS) is a progressive kidney disease characterized by glomerular collapse with epithelial hyperplasia. Here we used a transgenic mouse model of cFSGS with immunotoxin-induced podocyte-specific injury to determine the role for Notch signaling in its pathogenesis. The mice exhibited progressive loss of podocytes and severe proteinuria concomitant with histological features of cFSGS. Hyperplastic epithelium was negative for genetic podocyte tags, but positive for the parietal epithelial cell marker claudin-1, and expressed Notch1, Jagged1, and Hes1 mRNA and protein. Enhanced Notch mRNA expression induced by transforming growth factor-β1 in cultured parietal epithelial cells was associated with mesenchymal markers (α-smooth muscle actin, vimentin, and Snail1). Notch inhibition in vitro suppressed these phenotypic transcripts and Notch-dependent cell migration. Moreover, Notch inhibition in vivo significantly decreased parietal epithelial cell lesions but worsened proteinuria and histopathology in our cFSGS model. Thus, aberrant Notch1-mediated parietal epithelial cell migration with phenotypic changes appears to underlie the pathogenesis of cFSGS. Parietal epithelial cell hyperplasia may also represent an adaptive response to compensate for a disrupted filtration barrier with progressive podocyte loss.

  6. Targeting Notch signalling by the conserved miR-8/200 microRNA family in development and cancer cells

    PubMed Central

    Vallejo, Diana M; Caparros, Esther; Dominguez, Maria

    2011-01-01

    Notch signalling is crucial for the correct development and growth of numerous organs and tissues, and when subverted it can cause cancer. Loss of miR-8/200 microRNAs (miRNAs) is commonly observed in advanced tumours and correlates with their invasion and acquisition of stem-like properties. Here, we show that this miRNA family controls Notch signalling activation in Drosophila and human cells. In an overexpression screen, we identified the Drosophila miR-8 as a potent inhibitor of Notch-induced overgrowth and tumour metastasis. Gain and loss of mir-8 provoked developmental defects reminiscent of impaired Notch signalling and we demonstrated that miR-8 directly inhibits Notch ligand Serrate. Likewise, miR-200c and miR-141 directly inhibited JAGGED1, impeding proliferation of human metastatic prostate cancer cells. It has been suggested that JAGGED1 may also be important for metastases. Although in metastatic cancer cells, JAGGED1 modestly regulated ZEB1, the miR-200c's target in invasion, studies in Drosophila revealed that only concurrent overexpression of Notch and Zfh1/ZEB1 induced tumour metastases. Together, these data define a new way to attenuate or boost Notch signalling that may have clinical interest. PMID:21224847

  7. Differential Regulation of NOTCH2 and NOTCH3 Contribute to Their Unique Functions in Vascular Smooth Muscle Cells*

    PubMed Central

    Baeten, Jeremy T.; Lilly, Brenda

    2015-01-01

    Notch signaling is a key regulator of vascular smooth muscle cell (VSMC) phenotypes, including differentiation, proliferation, and cell survival. However, the exact contribution of the individual Notch receptors has not been thoroughly delineated. In this study, we identify unique roles for NOTCH2 and NOTCH3 in regulating proliferation and cell survival in cultured VSMCs. Our results indicate that NOTCH2 inhibits PDGF-B-dependent proliferation and its expression is decreased by PDGF-B. In contrast, NOTCH3 promotes proliferation and receptor expression is increased by PDGF-B. Additionally, data show that NOTCH3, but not NOTCH2 protects VSMCs from apoptosis and apoptosis mediators degrade NOTCH3 protein. We identified three pro-survival genes specifically regulated by NOTCH3 in cultured VSMCs and in mouse aortas. This regulation is mediated through MAP kinase signaling, which we demonstrate can be activated by NOTCH3, but not NOTCH2. Overall, this study highlights discrete roles for NOTCH2 and NOTCH3 in VSMCs and connects these roles to specific upstream regulators that control their expression. PMID:25957400

  8. Notch signaling in lung diseases: focus on Notch1 and Notch3

    PubMed Central

    Zong, Dandan; Ouyang, Ruoyun; Li, Jinhua; Chen, Yan; Chen, Ping

    2016-01-01

    Notch signaling is an evolutionarily conserved cell–cell communication mechanism that plays a key role in lung homeostasis, injury and repair. The loss of regulation of Notch signaling, especially Notch1 and Notch3, has recently been linked to the pathogenesis of important lung diseases, in particular, chronic obstructive pulmonary disease (COPD), asthma, pulmonary fibrosis, pulmonary arterial hypertension (PAH), lung cancer and lung lesions in some congenital diseases. This review focuses on recent advances related to the mechanisms and the consequences of aberrant or absent Notch1/3 activity in the initiation and progression of lung diseases. Our increasing understanding of this signaling pathway offers great hope that manipulating Notch signaling may represent a promising alternative complementary therapeutic strategy in the future. PMID:27378579

  9. Current views on the role of Notch signaling and the pathogenesis of human leukemia

    PubMed Central

    2011-01-01

    The Notch signaling pathway is highly conserved from Drosophila to humans and plays an important role in the regulation of cellular proliferation, differentiation and apoptosis. Constitutive activation of Notch signaling has been shown to result in excessive cellular proliferation and a wide range of malignancies, including leukemia, glioblastoma and lung and breast cancers. Notch can also act as a tumor suppressor, and its inactivation has been associated with an increased risk of spontaneous squamous cell carcinoma. This minireview focuses on recent advances related to the mechanisms and roles of activated Notch1, Notch2, Notch3 and Notch4 signaling in human lymphocytic leukemia, myeloid leukemia and B cell lymphoma, as well as their significance, and recent advances in Notch-targeted therapies. PMID:22128846

  10. The Notch pathway regulates the Second Mitotic Wave cell cycle independently of bHLH proteins.

    PubMed

    Bhattacharya, Abhishek; Li, Ke; Quiquand, Manon; Rimesso, Gerard; Baker, Nicholas E

    2017-11-15

    Notch regulates both neurogenesis and cell cycle activity to coordinate precursor cell generation in the differentiating Drosophila eye. Mosaic analysis with mitotic clones mutant for Notch components was used to identify the pathway of Notch signaling that regulates the cell cycle in the Second Mitotic Wave. Although S phase entry depends on Notch signaling and on the transcription factor Su(H), the transcriptional co-activator Mam and the bHLH repressor genes of the E(spl)-Complex were not essential, although these are Su(H) coactivators and targets during the regulation of neurogenesis. The Second Mitotic Wave showed little dependence on ubiquitin ligases neuralized or mindbomb, and although the ligand Delta is required non-autonomously, partial cell cycle activity occurred in the absence of known Notch ligands. We found that myc was not essential for the Second Mitotic Wave. The Second Mitotic Wave did not require the HLH protein Extra macrochaetae, and the bHLH protein Daughterless was required only cell-nonautonomously. Similar cell cycle phenotypes for Daughterless and Atonal were consistent with requirement for neuronal differentiation to stimulate Delta expression, affecting Notch activity in the Second Mitotic Wave indirectly. Therefore Notch signaling acts to regulate the Second Mitotic Wave without activating bHLH gene targets. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. The putative Notch ligand HyJagged is a transmembrane protein present in all cell types of adult Hydra and upregulated at the boundary between bud and parent.

    PubMed

    Prexl, Andrea; Münder, Sandra; Loy, Bernhard; Kremmer, Elisabeth; Tischer, Susanne; Böttger, Angelika

    2011-09-07

    The Notch signalling pathway is conserved in pre-bilaterian animals. In the Cnidarian Hydra it is involved in interstitial stem cell differentiation and in boundary formation during budding. Experimental evidence suggests that in Hydra Notch is activated by presenilin through proteolytic cleavage at the S3 site as in all animals. However, the endogenous ligand for HvNotch has not been described yet. We have cloned a cDNA from Hydra, which encodes a bona-fide Notch ligand with a conserved domain structure similar to that of Jagged-like Notch ligands from other animals. Hyjagged mRNA is undetectable in adult Hydra by in situ hybridisation but is strongly upregulated and easily visible at the border between bud and parent shortly before bud detachment. In contrast, HyJagged protein is found in all cell types of an adult hydra, where it localises to membranes and endosomes. Co-localisation experiments showed that it is present in the same cells as HvNotch, however not always in the same membrane structures. The putative Notch ligand HyJagged is conserved in Cnidarians. Together with HvNotch it may be involved in the formation of the parent-bud boundary in Hydra. Moreover, protein distribution of both, HvNotch receptor and HyJagged indicate a more widespread function for these two transmembrane proteins in the adult hydra, which may be regulated by additional factors, possibly involving endocytic pathways.

  12. Notch intracellular domain deficiency in nuclear localization activity retains the ability to enhance neural stem cell character and block neurogenesis in mammalian brain development.

    PubMed

    Jang, Jiwon; Byun, Sung-Hyun; Han, Dasol; Lee, Junsub; Kim, Juwan; Lee, Nayeon; Kim, Inhee; Park, Soojeong; Ha, Soobong; Kwon, Mookwang; Ahn, Jyhyun; Chung, Woo-Jae; Kweon, Dae-Hyuk; Cho, Jae Youl; Kim, Sunyoung; Yoon, Keejung

    2014-12-01

    Notch has a broad range of regulatory functions in many developmental processes, including hematopoiesis, neurogenesis, and angiogenesis. Notch has several key functional regions such as the RBP-Jκ/CBF1 association module (RAM) domain, nuclear localization signals (NLS), and ankyrin (ANK) repeats. However, previous reports assessing the level of importance of these domains in the Notch signaling pathway are controversial. In this study, we have assessed the level of contribution of each Notch domain to the regulation of mammalian neural stem cells in vivo as well as in vitro. Reporter assays and real-time polymerase chain reactions show that the ANK repeats and RAM domain are indispensable to the transactivation of Notch target genes, whereas a nuclear export signal (NES)-fused Notch intracellular domain (NICD) mutant defective in nuclear localization exerts a level of activity comparable to unmodified NICD. Transactivational ability appears to be tightly coupled to Notch functions during brain development. Unlike ANK repeats and RAM domain deletion mutants, NES-NICD recapitulates NICD features such as promotion of astrogenesis at the expense of neurogenesis in vitro and enhancement of neural stem cell character in vivo. Our data support the previous observation that intranuclear localization is not essential to the oncogenesis of Notch1 in certain types of cells and imply the importance of the noncanonical Notch signaling pathway in the regulation of mammalian neural stem cells.

  13. Notch activates Wnt-4 signalling to control medio-lateral patterning of the pronephros.

    PubMed

    Naylor, Richard W; Jones, Elizabeth A

    2009-11-01

    Previous studies have highlighted a role for the Notch signalling pathway during pronephrogenesis in the amphibian Xenopus laevis, and in nephron development in the mammalian metanephros, yet a mechanism for this function remains elusive. Here, we further the understanding of how Notch signalling patterns the early X. laevis pronephros anlagen, a function that might be conserved in mammalian nephron segmentation. Our results indicate that early phase pronephric Notch signalling patterns the medio-lateral axis of the dorso-anterior pronephros anlagen, permitting the glomus and tubules to develop in isolation. We show that this novel function acts through the Notch effector gene hrt1 by upregulating expression of wnt4. Wnt-4 then patterns the proximal pronephric anlagen to establish the specific compartments that span the medio-lateral axis. We also identified pronephric expression of lunatic fringe and radical fringe that is temporally and spatially appropriate for a role in regulating Notch signalling in the dorso-anterior region of the pronephros anlagen. On the basis of these results, along with data from previous publications, we propose a mechanism by which the Notch signalling pathway regulates a Wnt-4 function that patterns the proximal pronephric anlagen.

  14. Osthole prevents cerebral ischemia-reperfusion injury via the Notch signaling pathway.

    PubMed

    Guan, Junhong; Wei, Xiangtai; Qu, Shengtao; Lv, Tao; Fu, Qiang; Yuan, Ye

    2017-08-01

    Stroke is a common cerebrovascular disease in aging populations, and constitutes the second highest principle cause of mortality and the principle cause of permanent disability, and ischemic stroke is the primary form. Osthole is a coumarin derivative extracted from the fruits of Cnidium monnieri (L.) Cusson. In this study, we established a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) in vivo and found that MCAO/R caused cerebral infarction, hippocampus neuronal injury and apoptosis, and also activated the Notch 1 signaling pathway. However, treatment with osthole further enhanced the activity of Notch 1 signaling and reduced the cerebral infarction as well as the hippocampus neuronal injury and apoptosis induced by MCAO/R in a dose-dependent manner. The same results were observed in a primary neuronal oxygen glucose deficiency/reperfusion (OGD/R) model in vitro, and the effect of osthole could be blocked by an inhibitor of Notch 1 signaling, N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine tert-butyl ester (DAPT). Therefore, we demonstrated that osthole injection prevented rat ischemia-reperfusion injury via activating the Notch 1 signaling pathway in vivo and in vitro in a dose-dependent manner, which may be significant for clinical treatment of ischemic stroke.

  15. Pathogenic Mutations Associated with Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy Differently Affect Jagged1 Binding and Notch3 Activity via the RBP/JK Signaling Pathway

    PubMed Central

    Joutel, Anne; Monet, Marie; Domenga, Valérie; Riant, Florence; Tournier-Lasserve, Elisabeth

    2004-01-01

    Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited vascular dementia characterized by the degeneration of smooth-muscle cells in small cerebral arteries. CADASIL is caused by mutations in NOTCH3, one of the four mammalian homologs to the Drosophila melanogaster NOTCH gene. Disease-associated mutations are distributed throughout the 34 epidermal growth factor–like repeats (EGFRs) that compose the extracellular domain of the Notch3 receptor and result in a loss or a gain of a cysteine residue in one of these EGFRs. In human adults, Notch3 expression is highly restricted to vascular smooth-muscle cells. In patients with CADASIL, there is an abnormal accumulation of Notch3 in the vessel. Molecular pathways linking NOTCH3 mutations to degeneration of vascular smooth-muscle cells are as yet poorly understood. In this study, we investigated the effect of CADASIL mutations on Notch3 activity. We studied five naturally occurring mutations: R90C and C212S, located in the previously identified mutational hotspot EGFR2–5; C428S, shown in this study to be located in the ligand-binding domain EGFR10–11; and C542Y and R1006C, located in EGFR13 and EGFR26, respectively. All five mutant proteins were correctly processed. The C428S and C542Y mutant receptors exhibited a significant reduction in Jagged1-induced transcriptional activity of a RBP/JK responsive luciferase reporter, relative to wild-type Notch3. Impaired signaling activity of these two mutants arose through different mechanisms; the C428S mutant lost its Jagged1-binding ability, whereas C542Y retained it but exhibited an impaired presentation to the cell surface. In contrast, the R90C, C212S, and R1006C mutants retained the ability to bind Jagged1 and were associated with apparently normal levels of signaling activity. We conclude that mutations in Notch3 differently affect Jagged1 binding and Notch3 signaling via the RBP/JK pathway. PMID:14714274

  16. TNF Inhibits Notch-1 in Skeletal Muscle Cells by Ezh2 and DNA Methylation Mediated Repression: Implications in Duchenne Muscular Dystrophy

    PubMed Central

    Acharyya, Swarnali; Sharma, Sudarshana M.; Cheng, Alfred S.; Ladner, Katherine J.; He, Wei; Kline, William; Wang, Huating; Ostrowski, Michael C.; Huang, Tim H.; Guttridge, Denis C.

    2010-01-01

    Background Classical NF-κB signaling functions as a negative regulator of skeletal myogenesis through potentially multiple mechanisms. The inhibitory actions of TNFα on skeletal muscle differentiation are mediated in part through sustained NF-κB activity. In dystrophic muscles, NF-κB activity is compartmentalized to myofibers to inhibit regeneration by limiting the number of myogenic progenitor cells. This regulation coincides with elevated levels of muscle derived TNFα that is also under IKKβ and NF-κB control. Methodology/Principal Findings Based on these findings we speculated that in DMD, TNFα secreted from myotubes inhibits regeneration by directly acting on satellite cells. Analysis of several satellite cell regulators revealed that TNFα is capable of inhibiting Notch-1 in satellite cells and C2C12 myoblasts, which was also found to be dependent on NF-κB. Notch-1 inhibition occurred at the mRNA level suggesting a transcriptional repression mechanism. Unlike its classical mode of action, TNFα stimulated the recruitment of Ezh2 and Dnmt-3b to coordinate histone and DNA methylation, respectively. Dnmt-3b recruitment was dependent on Ezh2. Conclusions/Significance We propose that in dystrophic muscles, elevated levels of TNFα and NF-κB inhibit the regenerative potential of satellite cells via epigenetic silencing of the Notch-1 gene. PMID:20814569

  17. The spatiotemporal order of signaling events unveils the logic of development signaling.

    PubMed

    Zhu, Hao; Owen, Markus R; Mao, Yanlan

    2016-08-01

    Animals from worms and insects to birds and mammals show distinct body plans; however, the embryonic development of diverse body plans with tissues and organs within is controlled by a surprisingly few signaling pathways. It is well recognized that combinatorial use of and dynamic interactions among signaling pathways follow specific logic to control complex and accurate developmental signaling and patterning, but it remains elusive what such logic is, or even, what it looks like. We have developed a computational model for Drosophila eye development with innovated methods to reveal how interactions among multiple pathways control the dynamically generated hexagonal array of R8 cells. We obtained two novel findings. First, the coupling between the long-range inductive signals produced by the proneural Hh signaling and the short-range restrictive signals produced by the antineural Notch and EGFR signaling is essential for generating accurately spaced R8s. Second, the spatiotemporal orders of key signaling events reveal a robust pattern of lateral inhibition conducted by Ato-coordinated Notch and EGFR signaling to collectively determine R8 patterning. This pattern, stipulating the orders of signaling and comparable to the protocols of communication, may help decipher the well-appreciated but poorly defined logic of developmental signaling. The model is available upon request. hao.zhu@ymail.com Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  18. Hippo Cascade Controls Lineage Commitment of Liver Tumors in Mice and Humans.

    PubMed

    Zhang, Shanshan; Wang, Jingxiao; Wang, Haichuan; Fan, Lingling; Fan, Biao; Zeng, Billy; Tao, Junyan; Li, Xiaolei; Che, Li; Cigliano, Antonio; Ribback, Silvia; Dombrowski, Frank; Chen, Bin; Cong, Wenming; Wei, Lixin; Calvisi, Diego F; Chen, Xin

    2018-04-01

    Primary liver cancer consists mainly of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). A subset of human HCCs expresses a ICC-like gene signature and is classified as ICC-like HCC. The Hippo pathway is a critical regulator of normal and malignant liver development. However, the precise function(s) of the Hippo cascade along liver carcinogenesis remain to be fully delineated. The role of the Hippo pathway in a murine mixed HCC/ICC model induced by activated forms of AKT and Ras oncogenes (AKT/Ras) was investigated. The authors demonstrated the inactivation of Hippo in AKT/Ras liver tumors leading to nuclear localization of Yap and TAZ. Coexpression of AKT/Ras with Lats2, which activates Hippo, or the dominant negative form of TEAD2 (dnTEAD2), which blocks Yap/TAZ activity, resulted in delayed hepatocarcinogenesis and elimination of ICC-like lesions in the liver. Mechanistically, Notch2 expression was found to be down-regulated by the Hippo pathway in liver tumors. Overexpression of Lats2 or dnTEAD2 in human HCC cell lines inhibited their growth and led to the decreased expression of ICC-like markers, as well as Notch2 expression. Altogether, this study supports the key role of the Hippo cascade in regulating the differentiation status of liver tumors. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  19. The spatiotemporal order of signaling events unveils the logic of development signaling

    PubMed Central

    Zhu, Hao; Owen, Markus R.; Mao, Yanlan

    2016-01-01

    Motivation: Animals from worms and insects to birds and mammals show distinct body plans; however, the embryonic development of diverse body plans with tissues and organs within is controlled by a surprisingly few signaling pathways. It is well recognized that combinatorial use of and dynamic interactions among signaling pathways follow specific logic to control complex and accurate developmental signaling and patterning, but it remains elusive what such logic is, or even, what it looks like. Results: We have developed a computational model for Drosophila eye development with innovated methods to reveal how interactions among multiple pathways control the dynamically generated hexagonal array of R8 cells. We obtained two novel findings. First, the coupling between the long-range inductive signals produced by the proneural Hh signaling and the short-range restrictive signals produced by the antineural Notch and EGFR signaling is essential for generating accurately spaced R8s. Second, the spatiotemporal orders of key signaling events reveal a robust pattern of lateral inhibition conducted by Ato-coordinated Notch and EGFR signaling to collectively determine R8 patterning. This pattern, stipulating the orders of signaling and comparable to the protocols of communication, may help decipher the well-appreciated but poorly defined logic of developmental signaling. Availability and implementation: The model is available upon request. Contact: hao.zhu@ymail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27153573

  20. The Role of Notch Signaling Pathway in Breast Cancer Pathogenesis

    DTIC Science & Technology

    2005-07-01

    breast cancer cells, I tested whether ErbB2 overexpression will cooperate with Notch in HMLE cells. While overexpression of activated Notch1 failed to...tyrosine kinase upstream of Ras normally found overexpressed in many breast cancers , also failed to transform HMLE cells. These observations suggested...cooperation between Notch1IC and ErbB2 signaling in transforming HMLE cells. Breast cancers typically do not harbor oncogenic Ras mutations; nevertheless

  1. Dynamic changes in global microRNAome and transcriptome reveal complex miRNA-mRNA regulated host response to Japanese Encephalitis Virus in microglial cells

    PubMed Central

    Kumari, Bharti; Jain, Pratistha; Das, Shaoli; Ghosal, Suman; Hazra, Bibhabasu; Trivedi, Ashish Chandra; Basu, Anirban; Chakrabarti, Jayprokas; Vrati, Sudhanshu; Banerjee, Arup

    2016-01-01

    Microglia cells in the brain play essential role during Japanese Encephalitis Virus (JEV) infection and may lead to change in microRNA (miRNA) and mRNA profile. These changes may together control disease outcome. Using Affymetrix microarray platform, we profiled cellular miRNA and mRNA expression at multiple time points during viral infection in human microglial (CHME3) cells. In silico analysis of microarray data revealed a phased pattern of miRNAs expression, associated with JEV replication and provided unique signatures of infection. Target prediction and pathway enrichment analysis identified anti correlation between differentially expressed miRNA and the gene expression at multiple time point which ultimately affected diverse signaling pathways including Notch signaling pathways in microglia. Activation of Notch pathway during JEV infection was demonstrated in vitro and in vivo. The expression of a subset of miRNAs that target multiple genes in Notch signaling pathways were suppressed and their overexpression could affect JEV induced immune response. Further analysis provided evidence for the possible presence of cellular competing endogenous RNA (ceRNA) associated with innate immune response. Collectively, our data provide a uniquely comprehensive view of the changes in the host miRNAs induced by JEV during cellular infection and identify Notch pathway in modulating microglia mediated inflammation. PMID:26838068

  2. Dynamic changes in global microRNAome and transcriptome reveal complex miRNA-mRNA regulated host response to Japanese Encephalitis Virus in microglial cells.

    PubMed

    Kumari, Bharti; Jain, Pratistha; Das, Shaoli; Ghosal, Suman; Hazra, Bibhabasu; Trivedi, Ashish Chandra; Basu, Anirban; Chakrabarti, Jayprokas; Vrati, Sudhanshu; Banerjee, Arup

    2016-02-03

    Microglia cells in the brain play essential role during Japanese Encephalitis Virus (JEV) infection and may lead to change in microRNA (miRNA) and mRNA profile. These changes may together control disease outcome. Using Affymetrix microarray platform, we profiled cellular miRNA and mRNA expression at multiple time points during viral infection in human microglial (CHME3) cells. In silico analysis of microarray data revealed a phased pattern of miRNAs expression, associated with JEV replication and provided unique signatures of infection. Target prediction and pathway enrichment analysis identified anti correlation between differentially expressed miRNA and the gene expression at multiple time point which ultimately affected diverse signaling pathways including Notch signaling pathways in microglia. Activation of Notch pathway during JEV infection was demonstrated in vitro and in vivo. The expression of a subset of miRNAs that target multiple genes in Notch signaling pathways were suppressed and their overexpression could affect JEV induced immune response. Further analysis provided evidence for the possible presence of cellular competing endogenous RNA (ceRNA) associated with innate immune response. Collectively, our data provide a uniquely comprehensive view of the changes in the host miRNAs induced by JEV during cellular infection and identify Notch pathway in modulating microglia mediated inflammation.

  3. Inhibition of TGF-β and NOTCH Signaling by Cutaneous Papillomaviruses

    PubMed Central

    Meyers, Jordan M.; Grace, Miranda; Uberoi, Aayushi; Lambert, Paul F.; Munger, Karl

    2018-01-01

    Infections with cutaneous papillomaviruses have been linked to cutaneous squamous cell carcinomas that arise in patients who suffer from a rare genetic disorder, epidermodysplasia verruciformis, or those who have experienced long-term, systemic immunosuppression following organ transplantation. The E6 proteins of the prototypical cutaneous human papillomavirus (HPV) 5 and HPV8 inhibit TGF-β and NOTCH signaling. The Mus musculus papillomavirus 1, MmuPV1, infects laboratory mouse strains and causes cutaneous skin warts that can progress to squamous cell carcinomas. MmuPV1 E6 shares biological and biochemical activities with HPV8 E6 including the ability to inhibit TGF-β and NOTCH signaling by binding the SMAD2/SMAD3 and MAML1 transcription factors, respectively. Inhibition of TGF-β and NOTCH signaling is linked to delayed differentiation and sustained proliferation of differentiating keratinocytes. Furthermore, the ability of MmuPV1 E6 to bind MAML1 is necessary for wart and cancer formation in experimentally infected mice. Hence, experimental MmuPV1 infection in mice will be a robust and valuable experimental system to dissect key aspects of cutaneous HPV infection, pathogenesis, and carcinogenesis. PMID:29568286

  4. DNER, an epigenetically modulated gene, regulates glioblastoma-derived neurosphere cell differentiation and tumor propagation.

    PubMed

    Sun, Peng; Xia, Shuli; Lal, Bachchu; Eberhart, Charles G; Quinones-Hinojosa, Alfredo; Maciaczyk, Jarek; Matsui, William; Dimeco, Francesco; Piccirillo, Sara M; Vescovi, Angelo L; Laterra, John

    2009-07-01

    Neurospheres derived from glioblastoma (GBM) and other solid malignancies contain neoplastic stem-like cells that efficiently propagate tumor growth and resist cytotoxic therapeutics. The primary objective of this study was to use histone-modifying agents to elucidate mechanisms by which the phenotype and tumor-promoting capacity of GBM-derived neoplastic stem-like cells are regulated. Using established GBM-derived neurosphere lines and low passage primary GBM-derived neurospheres, we show that histone deacetylase (HDAC) inhibitors inhibit growth, induce differentiation, and induce apoptosis of neoplastic neurosphere cells. A specific gene product induced by HDAC inhibition, Delta/Notch-like epidermal growth factor-related receptor (DNER), inhibited the growth of GBM-derived neurospheres, induced their differentiation in vivo and in vitro, and inhibited their engraftment and growth as tumor xenografts. The differentiating and tumor suppressive effects of DNER, a noncanonical Notch ligand, contrast with the previously established tumor-promoting effects of canonical Notch signaling in brain cancer stem-like cells. Our findings are the first to implicate noncanonical Notch signaling in the regulation of neoplastic stem-like cells and suggest novel neoplastic stem cell targeting treatment strategies for GBM and potentially other solid malignancies.

  5. HEY1 is expressed independent of NOTCH1 and is associated with poor prognosis in head and neck squamous cell carcinoma.

    PubMed

    Rettig, Eleni M; Bishop, Justin A; Agrawal, Nishant; Chung, Christine H; Sharma, Rajni; Zamuner, Fernando; Li, Ryan J; Koch, Wayne M; Califano, Joseph A; Guo, Theresa; Gaykalova, Daria A; Fakhry, Carole

    2018-07-01

    Notch signaling is frequently altered in head and neck squamous cell carcinoma (HNSCC). However, the nature and clinical implications of this dysregulation are not well understood. We previously described an association of transcriptionally active NOTCH1 Intracellular Domain (NICD1) immunohistochemical (IHC) expression pattern with high-risk pathologic characteristics. Here we further characterize Notch signaling in HNSCC. IHC expression patterns and clinicopathologic associations of Notch pathway molecules were evaluated among 78 tumors with known NOTCH1 mutation status. IHC was performed for JAG1, a NOTCH1 activating ligand, and HEY1, an NICD1 transcriptional target and Notch pathway activation marker. IHC pattern and H-score (% staining × intensity) were recorded and compared to clinicopathologic characteristics and survival. Survival was analyzed using Kaplan Meier method and Cox proportional hazards models (HR). JAG1 and NICD1 expression patterns were highly concordant among tumors without truncating NOTCH1 mutations (p < 0.001), but were dissimilar among tumors with truncating NOTCH1 mutations (p = 0.24). There was evidence for JAG1-independent NOTCH1 activation among seven tumors, all with wild-type NOTCH1. HEY1 expression was associated with neither JAG1 nor NICD1 expression, but was associated with NOTCH1 mutation status (p = 0.03). Twelve (16%) tumors expressed HEY1 but not NICD1. Higher HEY1 H-score was significantly associated with worse overall (adjusted hazard ratio [aHR] 2.0, 95% CI = 1.0-4.2) and disease-specific (aHR = 3.3, 95% CI = 1.4-7.9) survival, whereas JAG1 and NICD1 expression were not associated with survival. These findings suggest both NOTCH1-dependent and -independent HEY1 regulation, and imply a previously unrecognized prognostic role for HEY1 in HNSCC. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. HER2 expression identifies dynamic functional states within circulating breast cancer cells.

    PubMed

    Jordan, Nicole Vincent; Bardia, Aditya; Wittner, Ben S; Benes, Cyril; Ligorio, Matteo; Zheng, Yu; Yu, Min; Sundaresan, Tilak K; Licausi, Joseph A; Desai, Rushil; O'Keefe, Ryan M; Ebright, Richard Y; Boukhali, Myriam; Sil, Srinjoy; Onozato, Maristela L; Iafrate, Anthony J; Kapur, Ravi; Sgroi, Dennis; Ting, David T; Toner, Mehmet; Ramaswamy, Sridhar; Haas, Wilhelm; Maheswaran, Shyamala; Haber, Daniel A

    2016-09-01

    Circulating tumour cells in women with advanced oestrogen-receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer acquire a HER2-positive subpopulation after multiple courses of therapy. In contrast to HER2-amplified primary breast cancer, which is highly sensitive to HER2-targeted therapy, the clinical significance of acquired HER2 heterogeneity during the evolution of metastatic breast cancer is unknown. Here we analyse circulating tumour cells from 19 women with ER + /HER2 - primary tumours, 84% of whom had acquired circulating tumour cells expressing HER2. Cultured circulating tumour cells maintain discrete HER2 + and HER2 - subpopulations: HER2 + circulating tumour cells are more proliferative but not addicted to HER2, consistent with activation of multiple signalling pathways; HER2 - circulating tumour cells show activation of Notch and DNA damage pathways, exhibiting resistance to cytotoxic chemotherapy, but sensitivity to Notch inhibition. HER2 + and HER2 - circulating tumour cells interconvert spontaneously, with cells of one phenotype producing daughters of the opposite within four cell doublings. Although HER2 + and HER2 - circulating tumour cells have comparable tumour initiating potential, differential proliferation favours the HER2 + state, while oxidative stress or cytotoxic chemotherapy enhances transition to the HER2 - phenotype. Simultaneous treatment with paclitaxel and Notch inhibitors achieves sustained suppression of tumorigenesis in orthotopic circulating tumour cell-derived tumour models. Together, these results point to distinct yet interconverting phenotypes within patient-derived circulating tumour cells, contributing to progression of breast cancer and acquisition of drug resistance.

  7. Withaferin A inhibits in vivo growth of breast cancer cells accelerated by Notch2 knockdown.

    PubMed

    Kim, Su-Hyeong; Hahm, Eun-Ryeong; Arlotti, Julie A; Samanta, Suman K; Moura, Michelle B; Thorne, Stephen H; Shuai, Yongli; Anderson, Carolyn J; White, Alexander G; Lokshin, Anna; Lee, Joomin; Singh, Shivendra V

    2016-05-01

    The present study offers novel insights into the molecular circuitry of accelerated in vivo tumor growth by Notch2 knockdown in triple-negative breast cancer (TNBC) cells. Therapeutic vulnerability of Notch2-altered growth to a small molecule (withaferin A, WA) is also demonstrated. MDA-MB-231 and SUM159 cells were used for the xenograft studies. A variety of technologies were deployed to elucidate the mechanisms underlying tumor growth augmentation by Notch2 knockdown and its reversal by WA, including Fluorescence Molecular Tomography for measurement of tumor angiogenesis in live mice, Seahorse Flux analyzer for ex vivo measurement of tumor metabolism, proteomics, and Luminex-based cytokine profiling. Stable knockdown of Notch2 resulted in accelerated in vivo tumor growth in both cells reflected by tumor volume and/or latency. For example, the wet tumor weight from mice bearing Notch2 knockdown MDA-MB-231 cells was about 7.1-fold higher compared with control (P < 0.0001). Accelerated tumor growth by Notch2 knockdown was highly sensitive to inhibition by a promising steroidal lactone (WA) derived from a medicinal plant. Molecular underpinnings for tumor growth intensification by Notch2 knockdown included compensatory increase in Notch1 activation, increased cellular proliferation and/or angiogenesis, and increased plasma or tumor levels of growth stimulatory cytokines. WA administration reversed many of these effects providing explanation for its remarkable anti-cancer efficacy. Notch2 functions as a tumor growth suppressor in TNBC and WA offers a novel therapeutic strategy for restoring this function.

  8. Targeting Notch signalling pathway of cancer stem cells.

    PubMed

    Venkatesh, Vandana; Nataraj, Raghu; Thangaraj, Gopenath S; Karthikeyan, Murugesan; Gnanasekaran, Ashok; Kaginelli, Shanmukhappa B; Kuppanna, Gobianand; Kallappa, Chandrashekrappa Gowdru; Basalingappa, Kanthesh M

    2018-01-01

    Cancer stem cells (CSCs) have been defined as cells within tumor that possess the capacity to self-renew and to cause the heterogeneous lineages of cancer cells that comprise the tumor. CSCs have been increasingly identified in blood cancer, prostate, ovarian, lung, melanoma, pancreatic, colon, brain and many more malignancies. CSCs have slow growth rate and are resistant to chemotherapy and radiotherapy that lead to the failure of traditional current therapy. Eradicating the CSCs and recurrence, is promising aspect for the cure of cancer. The CSCs like any other stem cells activate the signal transduction pathways that involve the development and tissue homeostasis, which include Notch signaling pathway. The new treatment targets these pathway that control stem-cell replication, survival and differentiation that are under development. Notch inhibitors either single or in combination with chemotherapy drugs have been developed to treat cancer and its recurrence. This approach of targeting signaling pathway of CSCs represents a promising future direction for the therapeutic strategy to cure cancer.

  9. Differential Regulation of NOTCH2 and NOTCH3 Contribute to Their Unique Functions in Vascular Smooth Muscle Cells.

    PubMed

    Baeten, Jeremy T; Lilly, Brenda

    2015-06-26

    Notch signaling is a key regulator of vascular smooth muscle cell (VSMC) phenotypes, including differentiation, proliferation, and cell survival. However, the exact contribution of the individual Notch receptors has not been thoroughly delineated. In this study, we identify unique roles for NOTCH2 and NOTCH3 in regulating proliferation and cell survival in cultured VSMCs. Our results indicate that NOTCH2 inhibits PDGF-B-dependent proliferation and its expression is decreased by PDGF-B. In contrast, NOTCH3 promotes proliferation and receptor expression is increased by PDGF-B. Additionally, data show that NOTCH3, but not NOTCH2 protects VSMCs from apoptosis and apoptosis mediators degrade NOTCH3 protein. We identified three pro-survival genes specifically regulated by NOTCH3 in cultured VSMCs and in mouse aortas. This regulation is mediated through MAP kinase signaling, which we demonstrate can be activated by NOTCH3, but not NOTCH2. Overall, this study highlights discrete roles for NOTCH2 and NOTCH3 in VSMCs and connects these roles to specific upstream regulators that control their expression. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. Alk1 and Alk5 inhibition by Nrp1 controls vascular sprouting downstream of Notch.

    PubMed

    Aspalter, Irene Maria; Gordon, Emma; Dubrac, Alexandre; Ragab, Anan; Narloch, Jarek; Vizán, Pedro; Geudens, Ilse; Collins, Russell Thomas; Franco, Claudio Areias; Abrahams, Cristina Luna; Thurston, Gavin; Fruttiger, Marcus; Rosewell, Ian; Eichmann, Anne; Gerhardt, Holger

    2015-06-17

    Sprouting angiogenesis drives blood vessel growth in healthy and diseased tissues. Vegf and Dll4/Notch signalling cooperate in a negative feedback loop that specifies endothelial tip and stalk cells to ensure adequate vessel branching and function. Current concepts posit that endothelial cells default to the tip-cell phenotype when Notch is inactive. Here we identify instead that the stalk-cell phenotype needs to be actively repressed to allow tip-cell formation. We show this is a key endothelial function of neuropilin-1 (Nrp1), which suppresses the stalk-cell phenotype by limiting Smad2/3 activation through Alk1 and Alk5. Notch downregulates Nrp1, thus relieving the inhibition of Alk1 and Alk5, thereby driving stalk-cell behaviour. Conceptually, our work shows that the heterogeneity between neighbouring endothelial cells established by the lateral feedback loop of Dll4/Notch utilizes Nrp1 levels as the pivot, which in turn establishes differential responsiveness to TGF-β/BMP signalling.

  11. Alk1 and Alk5 inhibition by Nrp1 controls vascular sprouting downstream of Notch

    PubMed Central

    Aspalter, Irene Maria; Gordon, Emma; Dubrac, Alexandre; Ragab, Anan; Narloch, Jarek; Vizán, Pedro; Geudens, Ilse; Collins, Russell Thomas; Franco, Claudio Areias; Abrahams, Cristina Luna; Thurston, Gavin; Fruttiger, Marcus; Rosewell, Ian; Eichmann, Anne; Gerhardt, Holger

    2015-01-01

    Sprouting angiogenesis drives blood vessel growth in healthy and diseased tissues. Vegf and Dll4/Notch signalling cooperate in a negative feedback loop that specifies endothelial tip and stalk cells to ensure adequate vessel branching and function. Current concepts posit that endothelial cells default to the tip-cell phenotype when Notch is inactive. Here we identify instead that the stalk-cell phenotype needs to be actively repressed to allow tip-cell formation. We show this is a key endothelial function of neuropilin-1 (Nrp1), which suppresses the stalk-cell phenotype by limiting Smad2/3 activation through Alk1 and Alk5. Notch downregulates Nrp1, thus relieving the inhibition of Alk1 and Alk5, thereby driving stalk-cell behaviour. Conceptually, our work shows that the heterogeneity between neighbouring endothelial cells established by the lateral feedback loop of Dll4/Notch utilizes Nrp1 levels as the pivot, which in turn establishes differential responsiveness to TGF-β/BMP signalling. PMID:26081042

  12. The putative Notch ligand HyJagged is a transmembrane protein present in all cell types of adult Hydra and upregulated at the boundary between bud and parent

    PubMed Central

    2011-01-01

    Background The Notch signalling pathway is conserved in pre-bilaterian animals. In the Cnidarian Hydra it is involved in interstitial stem cell differentiation and in boundary formation during budding. Experimental evidence suggests that in Hydra Notch is activated by presenilin through proteolytic cleavage at the S3 site as in all animals. However, the endogenous ligand for HvNotch has not been described yet. Results We have cloned a cDNA from Hydra, which encodes a bona-fide Notch ligand with a conserved domain structure similar to that of Jagged-like Notch ligands from other animals. Hyjagged mRNA is undetectable in adult Hydra by in situ hybridisation but is strongly upregulated and easily visible at the border between bud and parent shortly before bud detachment. In contrast, HyJagged protein is found in all cell types of an adult hydra, where it localises to membranes and endosomes. Co-localisation experiments showed that it is present in the same cells as HvNotch, however not always in the same membrane structures. Conclusions The putative Notch ligand HyJagged is conserved in Cnidarians. Together with HvNotch it may be involved in the formation of the parent-bud boundary in Hydra. Moreover, protein distribution of both, HvNotch receptor and HyJagged indicate a more widespread function for these two transmembrane proteins in the adult hydra, which may be regulated by additional factors, possibly involving endocytic pathways. PMID:21899759

  13. The Endocannabinoid, Anandamide, Augments Notch-1 Signaling in Cultured Cortical Neurons Exposed to Amyloid-β and in the Cortex of Aged Rats*

    PubMed Central

    Tanveer, Riffat; Gowran, Aoife; Noonan, Janis; Keating, Sinead E.; Bowie, Andrew G.; Campbell, Veronica A.

    2012-01-01

    Aberrant Notch signaling has recently emerged as a possible mechanism for the altered neurogenesis, cognitive impairment, and learning and memory deficits associated with Alzheimer disease (AD). Recently, targeting the endocannabinoid system in models of AD has emerged as a potential approach to slow the progression of the disease process. Although studies have identified neuroprotective roles for endocannabinoids, there is a paucity of information on modulation of the pro-survival Notch pathway by endocannabinoids. In this study the influence of the endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol, on the Notch-1 pathway and on its endogenous regulators were investigated in an in vitro model of AD. We report that AEA up-regulates Notch-1 signaling in cultured neurons. We also provide evidence that although Aβ1–42 increases expression of the endogenous inhibitor of Notch-1, numb (Nb), this can be prevented by AEA and 2-arachidonoylglycerol. Interestingly, AEA up-regulated Nct expression, a component of γ-secretase, and this was found to play a crucial role in the enhanced Notch-1 signaling mediated by AEA. The stimulatory effects of AEA on Notch-1 signaling persisted in the presence of Aβ1–42. AEA was found to induce a preferential processing of Notch-1 over amyloid precursor protein to generate Aβ1–40. Aging, a natural process of neurodegeneration, was associated with a reduction in Notch-1 signaling in rat cortex and hippocampus, and this was restored with chronic treatment with URB 597. In summary, AEA has the proclivity to enhance Notch-1 signaling in an in vitro model of AD, which may have relevance for restoring neurogenesis and cognition in AD. PMID:22891244

  14. Tissue Regeneration and Biomineralization in Sea Urchins: Role of Notch Signaling and Presence of Stem Cell Markers

    PubMed Central

    Reinardy, Helena C.; Emerson, Chloe E.; Manley, Jason M.; Bodnar, Andrea G.

    2015-01-01

    Echinoderms represent a phylum with exceptional regenerative capabilities that can reconstruct both external appendages and internal organs. Mechanistic understanding of the cellular pathways involved in regeneration in these animals has been hampered by the limited genomic tools and limited ability to manipulate regenerative processes. We present a functional assay to investigate mechanisms of tissue regeneration and biomineralization by measuring the regrowth of amputated tube feet (sensory and motor appendages) and spines in the sea urchin, Lytechinus variegatus. The ability to manipulate regeneration was demonstrated by concentration-dependent inhibition of regrowth of spines and tube feet by treatment with the mitotic inhibitor, vincristine. Treatment with the gamma-secretase inhibitor DAPT resulted in a concentration-dependent inhibition of regrowth, indicating that both tube feet and spine regeneration require functional Notch signaling. Stem cell markers (Piwi and Vasa) were expressed in tube feet and spine tissue, and Vasa-positive cells were localized throughout the epidermis of tube feet by immunohistochemistry, suggesting the existence of multipotent progenitor cells in these highly regenerative appendages. The presence of Vasa protein in other somatic tissues (e.g. esophagus, radial nerve, and a sub-population of coelomocytes) suggests that multipotent cells are present throughout adult sea urchins and may contribute to normal homeostasis in addition to regeneration. Mechanistic insight into the cellular pathways governing the tremendous regenerative capacity of echinoderms may reveal processes that can be modulated for regenerative therapies, shed light on the evolution of regeneration, and enable the ability to predict how these processes will respond to changing environmental conditions. PMID:26267358

  15. Kynurenine promotes the goblet cell differentiation of HT-29 colon carcinoma cells by modulating Wnt, Notch and AhR signals.

    PubMed

    Park, Joo-Hung; Lee, Jeong-Min; Lee, Eun-Jin; Kim, Da-Jeong; Hwang, Won-Bhin

    2018-04-01

    Various amino acids regulate cell growth and differentiation. In the present study, we examined the ability of HT-29 cells to differentiate into goblet cells in RPMI and DMEM which are largely different in the amounts of numerous amino acids. Most of the HT-29 cells differentiated into goblet cells downregulating the stem cell marker Lgr5 when cultured in DMEM, but remained undifferentiated in RPMI. The goblet cell differentiation in DMEM was inhibited by 1-methyl-tryptophan (1-MT), an inhibitor of indoleamine 2,3 dioxygenase-1 which is the initial enzyme in tryptophan metabolism along the kynurenine (KN) pathway, whereas tryptophan and KN induced goblet cell differentiation in RPMI. The levels of Notch1 and its activation product Notch intracytoplasmic domain in HT-29 cells were lower in DMEM than those in RPMI and were increased by 1-MT in both media. HT-29 cells grown in both media expressed β-catenin at the same level on day 2 when goblet cell differentiation was not observed. β-catenin expression, which was increased by 1-MT in both media, was decreased by KN. DMEM reduced Hes1 expression while enhancing Hath1 expression. Finally, aryl hydrocarbon receptor (AhR) activation moderately induced goblet cell differentiation. Our results suggest that KN promotes goblet cell differentiation by regulating Wnt, Notch, and AhR signals and expression of Hes1 and Hath1.

  16. Structural and functional characterization of the NHR1 domain of the Drosophila neuralized E3 ligase in the notch signaling pathway.

    PubMed

    He, Fahu; Saito, Kohei; Kobayashi, Naohiro; Harada, Takushi; Watanabe, Satoru; Kigawa, Takanori; Güntert, Peter; Ohara, Osamu; Tanaka, Akiko; Unzai, Satoru; Muto, Yutaka; Yokoyama, Shigeyuki

    2009-10-23

    The Notch signaling pathway is critical for many developmental processes and requires complex trafficking of both Notch receptor and its ligands, Delta and Serrate. In Drosophila melanogaster, the endocytosis of Delta in the signal-sending cell is essential for Notch receptor activation. The Neuralized protein from D. melanogaster (Neur) is a ubiquitin E3 ligase, which binds to Delta through its first neuralized homology repeat 1 (NHR1) domain and mediates the ubiquitination of Delta for endocytosis. Tom, a Bearded protein family member, inhibits the Neur-mediated endocytosis through interactions with the NHR1 domain. We have identified the domain boundaries of the novel NHR1 domain, using a screening system based on our cell-free protein synthesis method, and demonstrated that the identified Neur NHR1 domain had binding activity to the 20-residue peptide corresponding to motif 2 of Tom by isothermal titration calorimetry experiments. We also determined the solution structure of the Neur NHR1 domain by heteronuclear NMR methods, using a (15)N/(13)C-labeled sample. The Neur NHR1 domain adopts a characteristic beta-sandwich fold, consisting of a concave five-stranded antiparallel beta-sheet and a convex seven-stranded antiparallel beta-sheet. The long loop (L6) between the beta6 and beta7 strands covers the hydrophobic patch on the concave beta-sheet surface, and the Neur NHR1 domain forms a compact globular fold. Intriguingly, in spite of the slight, but distinct, differences in the topology of the secondary structure elements, the structure of the Neur NHR1 domain is quite similar to those of the B30.2/SPRY domains, which are known to mediate specific protein-protein interactions. Further NMR titration experiments of the Neur NHR1 domain with the 20-residue Tom peptide revealed that the resonances originating from the bottom area of the beta-sandwich (the L3, L5, and L11 loops, as well as the tip of the L6 loop) were affected. In addition, a structural comparison of the Neur NHR1 domain with the first NHR domain of the human KIAA1787 protein, which is from another NHR subfamily and does not bind to the 20-residue Tom peptide, suggested the critical amino acid residues for the interactions between the Neur NHR1 domain and the Tom peptide. The present structural study will shed light on the role of the Neur NHR1 domain in the Notch signaling pathway.

  17. Neural stem cell quiescence and stemness are molecularly distinct outputs of the Notch3 signalling cascade in the vertebrate adult brain.

    PubMed

    Than-Trong, Emmanuel; Ortica-Gatti, Sara; Mella, Sébastien; Nepal, Chirag; Alunni, Alessandro; Bally-Cuif, Laure

    2018-05-15

    Neural stem cells (NSCs) in the adult vertebrate brain are found in a quiescent state and can preserve long-lasting progenitor potential (stemness). Whether and how these two properties are linked, and to what extent they can be independently controlled by NSC maintenance pathways, is unresolved. We have previously identified Notch3 signalling as a major quiescence-promoting pathway in adult NSCs of the zebrafish pallium. We now show that Notch3 also controls NSC stemness. Using parallel transcriptomic characterizations of notch3 mutant NSCs and adult NSC physiological states, we demonstrate that a set of potentially direct Notch3 target genes distinguishes quiescence and stemness control. As a proof of principle, we focus on one 'stemness' target, encoding the bHLH transcription factor Hey1, that has not yet been analysed in adult NSCs. We show that abrogation of Hey1 function in adult pallial NSCs in vivo , including quiescent NSCs, leads to their differentiation without affecting their proliferation state. These results demonstrate that quiescence and stemness are molecularly distinct outputs of Notch3 signalling, and identify Hey1 as a major Notch3 effector controlling NSC stemness in the vertebrate adult brain. © 2018. Published by The Company of Biologists Ltd.

  18. Neural stem cell quiescence and stemness are molecularly distinct outputs of the Notch3 signalling cascade in the vertebrate adult brain

    PubMed Central

    Than-Trong, Emmanuel; Ortica-Gatti, Sara; Mella, Sébastien; Nepal, Chirag; Alunni, Alessandro

    2018-01-01

    ABSTRACT Neural stem cells (NSCs) in the adult vertebrate brain are found in a quiescent state and can preserve long-lasting progenitor potential (stemness). Whether and how these two properties are linked, and to what extent they can be independently controlled by NSC maintenance pathways, is unresolved. We have previously identified Notch3 signalling as a major quiescence-promoting pathway in adult NSCs of the zebrafish pallium. We now show that Notch3 also controls NSC stemness. Using parallel transcriptomic characterizations of notch3 mutant NSCs and adult NSC physiological states, we demonstrate that a set of potentially direct Notch3 target genes distinguishes quiescence and stemness control. As a proof of principle, we focus on one ‘stemness’ target, encoding the bHLH transcription factor Hey1, that has not yet been analysed in adult NSCs. We show that abrogation of Hey1 function in adult pallial NSCs in vivo, including quiescent NSCs, leads to their differentiation without affecting their proliferation state. These results demonstrate that quiescence and stemness are molecularly distinct outputs of Notch3 signalling, and identify Hey1 as a major Notch3 effector controlling NSC stemness in the vertebrate adult brain. PMID:29695612

  19. Roles for miR-375 in Neuroendocrine Differentiation and Tumor Suppression via Notch Pathway Suppression in Merkel Cell Carcinoma.

    PubMed

    Abraham, Karan J; Zhang, Xiao; Vidal, Ricardo; Paré, Geneviève C; Feilotter, Harriet E; Tron, Victor A

    2016-04-01

    Dysfunction of key miRNA pathways regulating basic cellular processes is a common driver of many cancers. However, the biological roles and/or clinical applications of such pathways in Merkel cell carcinoma (MCC), a rare but lethal cutaneous neuroendocrine (NE) malignancy, have yet to be determined. Previous work has established that miR-375 is highly expressed in MCC tumors, but its biological role in MCC remains unknown. Herein, we show that elevated miR-375 expression is a specific feature of well-differentiated MCC cell lines that express NE markers. In contrast, miR-375 is strikingly down-regulated in highly aggressive, undifferentiated MCC cell lines. Enforced miR-375 expression in these cells induced NE differentiation, and opposed cancer cell viability, migration, invasion, and survival, pointing to tumor-suppressive roles for miR-375. Mechanistically, miR-375-driven phenotypes were caused by the direct post-transcriptional repression of multiple Notch pathway proteins (Notch2 and RBPJ) linked to cancer and regulation of cell fate. Thus, we detail a novel molecular axis linking tumor-suppressive miR-375 and Notch with NE differentiation and cancer cell behavior in MCC. Our findings identify miR-375 as a putative regulator of NE differentiation, provide insight into the cell of origin of MCC, and suggest that miR-375 silencing may promote aggressive cancer cell behavior through Notch disinhibition. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  20. The Hippo signaling pathway provides novel anti-cancer drug targets

    PubMed Central

    Bae, June Sung; Kim, Sun Mi; Lee, Ho

    2017-01-01

    The Hippo signaling pathway plays a crucial role in cell proliferation, apoptosis, differentiation, and development. Major effectors of the Hippo signaling pathway include the transcriptional co-activators Yes-associated protein 1 (YAP) and WW domain-containing transcription regulator protein 1 (TAZ). The transcriptional activities of YAP and TAZ are affected by interactions with proteins from many diverse signaling pathways as well as responses to the external environment. High YAP and TAZ activity has been observed in many cancer types, and functional dysregulation of Hippo signaling enhances the oncogenic properties of YAP and TAZ and promotes cancer development. Many biological elements, including mechanical strain on the cell, cell polarity/adhesion molecules, other signaling pathways (e.g., G-protein-coupled receptor, epidermal growth factor receptor, Wnt, Notch, and transforming growth factor β/bone morphogenic protein), and cellular metabolic status, can promote oncogenesis through synergistic association with components of the Hippo signaling pathway. Here, we review the signaling networks that interact with the Hippo signaling pathway and discuss the potential of using drugs that inhibit YAP and TAZ activity for cancer therapy. PMID:28035075

  1. The Hippo signaling pathway provides novel anti-cancer drug targets.

    PubMed

    Bae, June Sung; Kim, Sun Mi; Lee, Ho

    2017-02-28

    The Hippo signaling pathway plays a crucial role in cell proliferation, apoptosis, differentiation, and development. Major effectors of the Hippo signaling pathway include the transcriptional co-activators Yes-associated protein 1 (YAP) and WW domain-containing transcription regulator protein 1 (TAZ). The transcriptional activities of YAP and TAZ are affected by interactions with proteins from many diverse signaling pathways as well as responses to the external environment. High YAP and TAZ activity has been observed in many cancer types, and functional dysregulation of Hippo signaling enhances the oncogenic properties of YAP and TAZ and promotes cancer development. Many biological elements, including mechanical strain on the cell, cell polarity/adhesion molecules, other signaling pathways (e.g., G-protein-coupled receptor, epidermal growth factor receptor, Wnt, Notch, and transforming growth factor β/bone morphogenic protein), and cellular metabolic status, can promote oncogenesis through synergistic association with components of the Hippo signaling pathway. Here, we review the signaling networks that interact with the Hippo signaling pathway and discuss the potential of using drugs that inhibit YAP and TAZ activity for cancer therapy.

  2. High-Resolution Mapping of Structural Mutations in Prostate Cancer with Single Nucleotide Polymorphism Arrays

    DTIC Science & Technology

    2006-11-01

    study of the NCI60 panel of cancer cell lines [39]. More recently, amplifications of NOTCH3 were noted in ovarian tumors by an SNP array analysis...and the functional role of NOTCH3 was suggested by the ability to suppress cell proliferation by inhibiting NOTCH3 [40]. Allele-specific copy...Identified and functionally validated the oncogene MITF. 40 Park JT, Li M, Nakayama K, et al. Notch3 gene amplification in ovarian cancer. Cancer Res

  3. The EGF Repeat-Specific O-GlcNAc-Transferase Eogt Interacts with Notch Signaling and Pyrimidine Metabolism Pathways in Drosophila

    PubMed Central

    Müller, Reto; Jenny, Andreas; Stanley, Pamela

    2013-01-01

    The O-GlcNAc transferase Eogt modifies EGF repeats in proteins that transit the secretory pathway, including Dumpy and Notch. In this paper, we show that the Notch ligands Delta and Serrate are also substrates of Eogt, that mutation of a putative UDP-GlcNAc binding DXD motif greatly reduces enzyme activity, and that Eogt and the cytoplasmic O-GlcNAc transferase Ogt have distinct substrates in Drosophila larvae. Loss of Eogt is larval lethal and disrupts Dumpy functions, but does not obviously perturb Notch signaling. To identify novel genetic interactions with eogt, we investigated dominant modification of wing blister formation caused by knock-down of eogt. Unexpectedly, heterozygosity for several members of the canonical Notch signaling pathway suppressed wing blister formation. And importantly, extensive genetic interactions with mutants in pyrimidine metabolism were identified. Removal of pyrimidine synthesis alleles suppressed wing blister formation, while removal of uracil catabolism alleles was synthetic lethal with eogt knock-down. Therefore, Eogt may regulate protein functions by O-GlcNAc modification of their EGF repeats, and cellular metabolism by affecting pyrimidine synthesis and catabolism. We propose that eogt knock-down in the wing leads to metabolic and signaling perturbations that increase cytosolic uracil levels, thereby causing wing blister formation. PMID:23671640

  4. Part 1: Notch-sparing γ-secretase inhibitors: The identification of novel naphthyl and benzofuranyl amide analogs.

    PubMed

    Lu, Dai; Wei, Han-Xun; Zhang, Jing; Gu, Yongli; Osenkowski, Pamela; Ye, Wenjuan; Selkoe, Dennis J; Wolfe, Michael S; Augelli-Szafran, Corinne E

    2016-05-01

    γ-Secretase is one of two proteases directly involved in the production of the amyloid β-peptide (Aβ), which is pathogenic in Alzheimer's disease. Inhibition of γ-secretase to suppress the production of Aβ should not block processing of one of its alternative substrates, Notch1 receptors, as interference with Notch1 signaling leads to severe toxic effects. In the course of our studies to identify γ-secretase inhibitors with selectivity for APP over Notch, 1 [3-(benzyl(isopropyl)amino)-1-(naphthalen-2-yl)propan-1-one] was found to inhibit γ-secretase-mediated Aβ production without interfering with γ-secretase-mediated Notch processing in purified enzyme assays. As 1 is chemically unstable, efforts to increase the stability of this compound led to the identification of 2 [naphthalene-2-carboxylic acid benzyl-isopropyl-amide] which showed similar biological activity to compound 1. Synthesis and evaluation of a series of amide analogs resulted in benzofuranyl amide analogs that showed promising Notch-sparing γ-secretase inhibitory effects. This class of compounds may serve as a novel lead series for further study in the development of γ-secretase inhibitors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Nitric oxide-releasing sulindac is a novel skin cancer chemopreventive agent for UVB-induced photocarcinogenesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chaudhary, Sandeep C.; Singh, Tripti; Kapur, Puneet

    Nitric oxide (NO)-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) which have been synthesized to reduce gastro-intestinal and cardiovascular toxicities of NSAIDs, possess anti-proliferative, pro-apoptotic and anti-cancer activities. Here, we show that NO-sulindac inhibited UVB-induced skin tumorigenesis in SKH-1 hairless mice. Topical application of NO-sulindac reduced tumor incidence, number (p < 0.05) and volume (p < 0.005) as compared to UVB (alone)-irradiated vehicle-treated mice. An increase in TUNEL-positive cells in skin lesions was accompanied by the enhanced Bax:Bcl-2 ratio. The expression of pro-apoptotic Bax was increased whereas anti-apoptotic Bcl-2 reduced. However, proliferation was identified as the major target of NO-sulindac in this study.more » A reduced expression of PCNA and cyclin D1 associated with the dampening of cell cycle progression was observed. The mechanism of this inhibition was related to the reduction in UVB-induced Notch signaling pathway. UVB-induced inflammatory responses were diminished by NO-sulindac as observed by a remarkable reduction in the levels of phosphorylated MAP Kinases Erk1/2, p38 and JNK1/2. In this regard, NO-sulindac also inhibited NFκB by enhancing IκBα as evidenced by the reduced expression of iNOS and COX-2, the direct NFκB transcription target proteins. NO-sulindac significantly diminished the progression of benign lesions to invasive carcinomas by suppressing the tumor aggressiveness and retarding epithelial–mesenchymal transition. A marked decrease in the expression of mesenchymal markers such as Fibronectin, N-cadherin, SNAI, Slug and Twist and an increase in epithelial cell polarity marker E-cadherin were noted in NO-sulindac-treated tumors. Our data suggest that NO-sulindac is a potent inhibitor of UVB-induced skin carcinogenesis and acts by targeting proliferation-regulatory pathways. - Highlights: ► NO-sulindac is a potent chemopreventive agent for UVB-induced skin cancer. ► NO-sulindac effectively blocks proliferation. ► NO-sulindac targets Notch and RXR-PI3k/Akt pathway to achieve anti-tumor efficacy.« less

  6. Delta-like 1/Fetal Antigen-1 (Dlk1/FA1) Is a Novel Regulator of Chondrogenic Cell Differentiation via Inhibition of the Akt Kinase-dependent Pathway*

    PubMed Central

    Chen, Li; Qanie, Diyako; Jafari, Abbas; Taipaleenmaki, Hanna; Jensen, Charlotte H.; Säämänen, Anna-Marja; Sanz, Maria Luisa Nueda; Laborda, Jorge; Abdallah, Basem M.; Kassem, Moustapha

    2011-01-01

    Delta-like 1 (Dlk1, also known as fetal antigen-1, FA1) is a member of Notch/Delta family that inhibits adipocyte and osteoblast differentiation; however, its role in chondrogenesis is still not clear. Thus, we overexpressed Dlk1/FA1 in mouse embryonic ATDC5 cells and tested its effects on chondrogenic differentiation. Dlk1/FA1 inhibited insulin-induced chondrogenic differentiation as evidenced by reduction of cartilage nodule formation and gene expression of aggrecan, collagen Type II and X. Similar effects were obtained either by using Dlk1/FA1-conditioned medium or by addition of a purified, secreted, form of Dlk1 (FA1) directly to the induction medium. The inhibitory effects of Dlk1/FA1 were dose-dependent and occurred irrespective of the chondrogenic differentiation stage: proliferation, differentiation, maturation, or hypertrophic conversion. Overexpression or addition of the Dlk1/FA1 protein to the medium strongly inhibited the activation of Akt, but not the ERK1/2, or p38 MAPK pathways, and the inhibition of Akt by Dlk1/FA1 was mediated through PI3K activation. Interestingly, inhibition of fibronectin expression by siRNA rescued the Dlk1/FA1-mediated inhibition of Akt, suggesting interaction of Dlk1/FA1 and fibronectin in chondrogenic cells. Our results identify Dlk1/FA1 as a novel regulator of chondrogenesis and suggest Dlk1/FA1 acts as an inhibitor of the PI3K/Akt pathways that leads to its inhibitory effects on chondrogenesis. PMID:21724852

  7. Synergistic Effects of Multiple Natural Products in Pancreatic Cancer Cells

    PubMed Central

    Wang, Zhiwei; Desmoulin, Sita; Banerjee, Sanjeev; Kong, Dejuan; Li, Yiwei; Deraniyagala, Rohan L; Abbruzzese, James; Sarkar, Fazlul H.

    2008-01-01

    Pancreatic cancer (PC) remains the fourth most common cause of cancer related death in the United States. Therefore, novel strategies for the prevention and treatment are urgently needed. Numerous dietary and pharmacological agents have been proposed as alternative strategies for the prevention and/or treatment of PC. Isoflavone is a prominent flavonoid found in soy products and has been proposed to be responsible for lowering the incidence of PC in Asians. Similarly, curcumin, an active ingredient of turmeric, that inhibits growth of malignant neoplasms, has a promising role in the prevention and/or treatment of PC. Here we examined whether isoflavone together with curcumin could elicit a greater inhibition of growth of PC cells than either agent alone, and also sought to determine the molecular mechanism of action. We found that the inhibition of cell growth and induction of apoptosis was significantly greater in the combination group than that could be achieved by either agent alone. These changes were associated with decreased Notch-1 expression and DNA binding activity of NF-κB and its target genes such as Cyclin D1, Bcl-2, and Bcl-xL. Moreover, we found that the combination of four natural agents at lower concentration was much more effective. Collectively, our results suggest that diet containing multiple natural products should be preferable over single agents for the prevention and/or treatment of PC. The superior effects of the combinatorial treatment could partly be attributed to the inhibition of constitutive activation of Notch-1 and NF-κB signaling pathways. PMID:18640131

  8. NOTCH3 inactivation increases triple negative breast cancer sensitivity to gefitinib by promoting EGFR tyrosine dephosphorylation and its intracellular arrest.

    PubMed

    Diluvio, Giulia; Del Gaudio, Francesca; Giuli, Maria Valeria; Franciosa, Giulia; Giuliani, Eugenia; Palermo, Rocco; Besharat, Zein Mersini; Pignataro, Maria Gemma; Vacca, Alessandra; d'Amati, Giulia; Maroder, Marella; Talora, Claudio; Capalbo, Carlo; Bellavia, Diana; Checquolo, Saula

    2018-05-25

    Notch dysregulation has been implicated in numerous tumors, including triple-negative breast cancer (TNBC), which is the breast cancer subtype with the worst clinical outcome. However, the importance of individual receptors in TNBC and their specific mechanism of action remain to be elucidated, even if recent findings suggested a specific role of activated-Notch3 in a subset of TNBCs. Epidermal growth factor receptor (EGFR) is overexpressed in TNBCs but the use of anti-EGFR agents (including tyrosine kinase inhibitors, TKIs) has not been approved for the treatment of these patients, as clinical trials have shown disappointing results. Resistance to EGFR blockers is commonly reported. Here we show that Notch3-specific inhibition increases TNBC sensitivity to the TKI-gefitinib in TNBC-resistant cells. Mechanistically, we demonstrate that Notch3 is able to regulate the activated EGFR membrane localization into lipid rafts microdomains, as Notch3 inhibition, such as rafts depletion, induces the EGFR internalization and its intracellular arrest, without involving receptor degradation. Interestingly, these events are associated with the EGFR tyrosine dephosphorylation at Y1173 residue (but not at Y1068) by the protein tyrosine phosphatase H1 (PTPH1), thus suggesting its possible involvement in the observed Notch3-dependent TNBC sensitivity response to gefitinib. Consistent with this notion, a nuclear localization defect of phospho-EGFR is observed after combined blockade of EGFR and Notch3, which results in a decreased TNBC cell survival. Notably, we observed a significant correlation between EGFR and NOTCH3 expression levels by in silico gene expression and immunohistochemical analysis of human TNBC primary samples. Our findings strongly suggest that combined therapies of TKI-gefitinib with Notch3-specific suppression may be exploited as a drug combination advantage in TNBC treatment.

  9. sequoia controls the type I>0 daughter proliferation switch in the developing Drosophila nervous system.

    PubMed

    Gunnar, Erika; Bivik, Caroline; Starkenberg, Annika; Thor, Stefan

    2016-10-15

    Neural progenitors typically divide asymmetrically to renew themselves, while producing daughters with more limited potential. In the Drosophila embryonic ventral nerve cord, neuroblasts initially produce daughters that divide once to generate two neurons/glia (type I proliferation mode). Subsequently, many neuroblasts switch to generating daughters that differentiate directly (type 0). This programmed type I>0 switch is controlled by Notch signaling, triggered at a distinct point of lineage progression in each neuroblast. However, how Notch signaling onset is gated was unclear. We recently identified Sequoia (Seq), a C2H2 zinc-finger transcription factor with homology to Drosophila Tramtrack (Ttk) and the positive regulatory domain (PRDM) family, as important for lineage progression. Here, we find that seq mutants fail to execute the type I>0 daughter proliferation switch and also display increased neuroblast proliferation. Genetic interaction studies reveal that seq interacts with the Notch pathway, and seq furthermore affects expression of a Notch pathway reporter. These findings suggest that seq may act as a context-dependent regulator of Notch signaling, and underscore the growing connection between Seq, Ttk, the PRDM family and Notch signaling. © 2016. Published by The Company of Biologists Ltd.

  10. Discrete Notch signaling requirements in the specification of hematopoietic stem cells

    PubMed Central

    Kim, Albert D; Melick, Chase H; Clements, Wilson K; Stachura, David L; Distel, Martin; Panáková, Daniela; MacRae, Calum; Mork, Lindsey A; Crump, J Gage; Traver, David

    2014-01-01

    Hematopoietic stem cells (HSCs) require multiple molecular inputs for proper specification, including activity of the Notch signaling pathway. A requirement for the Notch1 and dispensability of the Notch2 receptor has been demonstrated in mice, but the role of the remaining Notch receptors has not been investigated. Here, we demonstrate that three of the four Notch receptors are independently required for the specification of HSCs in the zebrafish. The orthologues of the murine Notch1 receptor, Notch1a and Notch1b, are each required intrinsically to fate HSCs, just prior to their emergence from aortic hemogenic endothelium. By contrast, the Notch3 receptor is required earlier within the developing somite to regulate HSC emergence in a non-cell-autonomous manner. Epistatic analyses demonstrate that Notch3 function lies downstream of Wnt16, which is required for HSC specification through its regulation of two Notch ligands, dlc and dld. Collectively, these findings demonstrate for the first time that multiple Notch signaling inputs are required to specify HSCs and that Notch3 performs a novel role within the somite to regulate the neighboring precursors of hemogenic endothelium. PMID:25230933

  11. Notch signaling regulates expression of Mcl-1 and apoptosis in PPD-treated macrophages.

    PubMed

    Palaga, Tanapat; Ratanabunyong, Siriluk; Pattarakankul, Thitiporn; Sangphech, Naunpun; Wongchana, Wipawee; Hadae, Yukihiro; Kueanjinda, Patipark

    2013-09-01

    Macrophages are cellular targets for infection by bacteria and viruses. The fate of infected macrophages plays a key role in determining the outcome of the host immune response. Apoptotic cell death of macrophages is considered to be a protective host defense that eliminates pathogens and infected cells. In this study, we investigated the involvement of Notch signaling in regulating apoptosis in macrophages treated with tuberculin purified protein derivative (PPD). Murine bone marrow-derived macrophages (BMMs) treated with PPD or infected with Mycobacterium bovis Bacillus Calmette-Guérin (BCG) induced upregulation of Notch1. This upregulation correlated well with the upregulation of the anti-apoptotic gene mcl-1 both at the transcriptional and translational levels. Decreased levels of Notch1 and Mcl-1 were observed in BMM treated with PPD when a gamma secretase inhibitor (GSI), which inhibits the processing of Notch receptors, was used. Moreover, silencing Notch1 in the macrophage-like cell line RAW264.7 decreased Mcl-1 protein expression, suggesting that Notch1 is critical for Mcl-1 expression in macrophages. A significant increase in apoptotic cells was observed upon treatment of BMM with PPD in the presence of GSI compared to the vehicle-control treated cells. Finally, analysis of the mcl-1 promoter in humans and mice revealed a conserved potential CSL/RBP-Jκ binding site. The association of Notch1 with the mcl-1 promoter was confirmed by chromatin immunoprecipitation. Taken together, these results indicate that Notch1 inhibits apoptosis of macrophages stimulated with PPD by directly controlling the mcl-1 promoter.

  12. Immunohistochemical expression of Notch signaling in the lining epithelium of periapical cysts.

    PubMed

    Meliou, Eleni; Kerezoudis, Nikolaos; Tosios, Konstantinos; Lafkas, Daniel; Kiaris, Hippokratis

    2011-02-01

    In this study we evaluated the immunohistochemical expression of the receptors Notch 1 and Notch 2, the ligand Delta 1, and the transcription factors HES 1 and HES 5 in the epithelium of well-defined periapical cysts. Immunohistochemistry was carried out on 55 formalin-fixed and paraffin-embedded, well-defined periapical cysts with minimum inflammation, obtained from the archival tissue database of the Department of Oral Pathology and Surgery. Western blotting was performed to evaluate the specificity of the anti-Notch antibody and the expression of Notch signaling in 5 fresh-frozen periapical cysts. The levels of staining intensity were estimated by the performance of a semiautomated image analysis system. Descriptive statistic of mean values obtained by computerized image analysis method was performed. Immunostaining reaction of all Notch signaling components was observed in the cytoplasm and/or the cytoplasmic membrane in the majority of epithelial cells of periapical cysts. Nuclear staining was observed occasionally in all cases. Notch 2 showed strong staining in 52.83% of the cases, followed by Notch 1 (35.85%), HES 1 and HES 5 moderate staining in 72.73% and 57.69% of the cases, respectively, and Delta 1 weak staining in 58.33% of the cases. No statistical correlation was found between the antibodies and the sex or the age of the study group. Notch is an evolutionarily conserved signaling mechanism that regulates cell fate decisions during development and postnatal life in organisms as diverse as worms, flies, and humans. The present observations indicate that Notch pathway is active downstream in the lining epithelium of periapical cysts, suggesting an involvement of this pathway in periapical cyst growth and expansion. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. No evidence for induction of key components of the Notch signaling pathway (Notch-1, Jagged-1) by treatment with UV-B, 1,25(OH)(2)D(3), and/or epigenetic drugs (TSA, 5-Aza) in human keratinocytes in vitro.

    PubMed

    Reichrath, Sandra; Reichrath, Jörg

    2012-01-01

    Notch signaling is of high importance for growth and survival of various cell types. We now analyzed the protein expression of two key components of the Notch signaling pathway (Notch-1, Jagged-1) in spontaneously immortalized (HaCaT) and in malignant (SCL-1) human keratinocytes, using western analysis. We found that Notch-1 and its corresponding ligand Jagged-1 are expressed in both cell lines, with no marked change following UV-B treatment. Moreover, treatment of both cell lines before or after UV-B irradiation with 1,25-dihydroxyvitamin D(3), the biologically active form of vitamin D, and/or epigenetic modulating drugs (TSA; 5-Aza) did not result in a marked modulation of the protein expression of Notch-1 or Jagged-1. Under the experimental conditions of this study, treatment with 1,25(OH)(2)D(3) protected human keratinocytes in part against the antiproliferative effects of UV-B-radiation. In conclusion, our findings do not point at a differential expression of these two key components of Notch signaling in non-malignant as compared to malignant human keratinocytes, indicating that alterations in their expression are not of importance for the photocarcinogenesis of human squamous cell carcinomas. Moreover, our findings do not support the hypothesis that modulation of Notch signaling may be involved in the photoprotective effect of 1,25-dihydroxyvitamin D(3), that we and others reported previously. Additionally, we demonstrate that epigenetic modulating drugs (TSA, 5-Aza) do not markedly modulate the expression Notch-1 or Jagged-1 in UV-B-treated human keratinocytes in vitro.

  14. Sequestration of latent TGF-β binding protein 1 into CADASIL-related Notch3-ECD deposits.

    PubMed

    Kast, Jessica; Hanecker, Patrizia; Beaufort, Nathalie; Giese, Armin; Joutel, Anne; Dichgans, Martin; Opherk, Christian; Haffner, Christof

    2014-08-13

    Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) represents the most common hereditary form of cerebral small vessel disease characterized by early-onset stroke and premature dementia. It is caused by mutations in the transmembrane receptor Notch3, which promote the aggregation and accumulation of the Notch3 extracellular domain (Notch3-ECD) within blood vessel walls. This process is believed to mediate the abnormal recruitment and dysregulation of additional factors including extracellular matrix (ECM) proteins resulting in brain vessel dysfunction. Based on recent evidence indicating a role for the transforming growth factor-β (TGF-β) pathway in sporadic and familial small vessel disease we studied fibronectin, fibrillin-1 and latent TGF-β binding protein 1 (LTBP-1), three ECM constituents involved in the regulation of TGF-β bioavailability, in post-mortem brain tissue from CADASIL patients and control subjects. Fibronectin and fibrillin-1 were found to be enriched in CADASIL vessels without co-localizing with Notch3-ECD deposits, likely as a result of fibrotic processes secondary to aggregate formation. In contrast, LTBP-1 showed both an accumulation and a striking co-localization with Notch3-ECD deposits suggesting specific recruitment into aggregates. We also detected increased levels of the TGF-β prodomain (also known as latency-associated peptide, LAP) indicating dysregulation of the TGF-β pathway in CADASIL development. In vitro analyses revealed a direct interaction between LTBP-1 and Notch3-ECD and demonstrated a specific co-aggregation of LTBP-1 with mutant Notch3. We propose LTBP-1 as a novel component of Notch3-ECD deposits and suggest its involvement in pathological processes triggered by Notch3-ECD aggregation.

  15. Activated Notch signaling cascade is correlated with stem cell differentiation toward absorptive progenitors after massive small bowel resection in a rat.

    PubMed

    Sukhotnik, Igor; Coran, Arnold G; Pollak, Yulia; Kuhnreich, Eviatar; Berkowitz, Drora; Saxena, Amulya K

    2017-09-01

    Notch signaling is thought to act to drive cell versification in the lining of the small intestine. The purpose of the present study was to evaluate the role of the Notch signaling pathway in stem cell differentiation in the late stages of intestinal adaptation after massive small bowel resection in a rat. Male Sprague-Dawley rats were randomly assigned to one of two experimental groups of eight rats each: Sham rats underwent bowel transection and reanastomosis, while SBS rats underwent 75% small bowel resection. Rats were euthanized on day 14 Illumina's Digital Gene Expression (DGE) analysis was used to determine Notch signaling gene expression profiling. Notch-related gene and protein expression was determined using real-time PCR, Western blot analysis, and immunohistochemistry. From seven investigated Notch-related (by DGE analysis) genes, six genes were upregulated in SBS vs. control animals with a relative change in gene expression level of 20% or more. A significant upregulation of Notch signaling-related genes in resected animals was accompanied by a significant increase in Notch-1 protein levels (Western blot analysis) and a significant increase in the number of Notch1 and Hes1 (target gene)-positive cells (immunohistochemistry) compared with sham animals. Evaluation of cell differentiation has shown a strong increase in total number of absorptive cells (unchanged secretory cells) compared with control rats. In conclusion, 2 wk after bowel resection in rats, stimulated Notch signaling directs the crypt cell population toward absorptive progenitors. NEW & NOTEWORTHY This study provides novel insight into the mechanisms of cell proliferation following massive small bowel resection. We show that 2 wk after bowel resection in rats, enhanced stem cell activity was associated with stimulated Notch signaling pathway. We demonstrate that activated Notch signaling cascade directs the crypt cell population toward absorptive progenitors. Copyright © 2017 the American Physiological Society.

  16. Notch signalling in T cell lymphoblastic leukaemia/lymphoma and other haematological malignancies

    PubMed Central

    Aster, Jon C.; Blacklow, Stephen C.; Pear, Warren S.

    2010-01-01

    Notch receptors participate in a highly conserved signalling pathway that regulates normal development and tissue homeostasis in a context- and dose-dependent manner. Deregulated Notch signalling has been implicated in many diseases, but the clearest example of a pathogenic role is found in T cell lymphoblastic leukaemia/lymphoma (T-LL), in which the majority of human and murine tumours have acquired mutations that lead to aberrant increases in Notch1 signalling. Remarkably, it appears that the selective pressure for Notch mutations is virtually unique among cancers to T-LL, presumably reflecting a special context-dependent role for Notch in normal T cell progenitors. Nevertheless, there are some recent reports suggesting that Notch signalling has subtle yet important roles in other forms of hematologic malignancy as well. Here, we review the role of Notch signalling in various blood cancers, focusing on T-LL with an eye toward targeted therapeutics. PMID:20967796

  17. Structure and Function of the Mind bomb E3 ligase in the context of Notch Signal Transduction

    PubMed Central

    Guo, Bingqian; McMillan, Brian J.; Blacklow, Stephen C.

    2016-01-01

    The Notch signaling pathway has a critical role in cell fate determination and tissue homeostasis in a variety of different lineages. In the context of normal Notch signaling, the Notch receptor of the “signal-receiving” cell is activated in trans by a Notch ligand from a neighboring “signal-sending” cell. Genetic studies in several model organisms have established that ubiquitination of the Notch ligand, and its regulated endocytosis, is essential for transmission of this activation signal. In mammals, this ubiquitination step is dependent on the protein Mind bomb 1 (Mib1), a large multi-domain RING-type E3 ligase, and its direct interaction with the intracellular tails of Notch ligand molecules. Here, we discuss our current understanding of Mind bomb structure and mechanism in the context of Notch signaling and beyond. PMID:27285058

  18. Novel Roles for Notch3 and Notch4 Receptors in Gene Expression and Susceptibility to Ozone-Induced Lung Inflammation in Mice.

    PubMed

    Verhein, Kirsten C; McCaw, Zachary; Gladwell, Wesley; Trivedi, Shweta; Bushel, Pierre R; Kleeberger, Steven R

    2015-08-01

    Ozone is a highly toxic air pollutant and global health concern. Mechanisms of genetic susceptibility to ozone-induced lung inflammation are not completely understood. We hypothesized that Notch3 and Notch4 are important determinants of susceptibility to ozone-induced lung inflammation. Wild-type (WT), Notch3 (Notch3-/-), and Notch4 (Notch4-/-) knockout mice were exposed to ozone (0.3 ppm) or filtered air for 6-72 hr. Relative to air-exposed controls, ozone increased bronchoalveolar lavage fluid (BALF) protein, a marker of lung permeability, in all genotypes, but significantly greater concentrations were found in Notch4-/- compared with WT and Notch3-/- mice. Significantly greater mean numbers of BALF neutrophils were found in Notch3-/- and Notch4-/- mice compared with WT mice after ozone exposure. Expression of whole lung Tnf was significantly increased after ozone in Notch3-/- and Notch4-/- mice, and was significantly greater in Notch3-/- compared with WT mice. Statistical analyses of the transcriptome identified differentially expressed gene networks between WT and knockout mice basally and after ozone, and included Trim30, a member of the inflammasome pathway, and Traf6, an inflammatory signaling member. These novel findings are consistent with Notch3 and Notch4 as susceptibility genes for ozone-induced lung injury, and suggest that Notch receptors protect against innate immune inflammation.

  19. Molecular mechanisms underlying osteoarthritis development: Notch and NF-κB.

    PubMed

    Saito, Taku; Tanaka, Sakae

    2017-05-15

    Osteoarthritis (OA) is a multi-factorial and highly prevalent joint disorder worldwide. Since the establishment of murine surgical knee OA models in 2005, many of the key molecules and signalling pathways responsible for OA development have been identified. Here we review the roles of two multi-functional signalling pathways in OA development: Notch and nuclear factor kappa-light-chain-enhancer of activated B cells. Previous studies have identified various aspects of articular chondrocyte regulation by these pathways. However, comprehensive understanding of the molecular networks regulating articular cartilage homeostasis and OA pathogenesis is needed.

  20. Conserved Genetic Pathways Controlling the Development of the Diffuse Endocrine System in Vertebrates and Drosophila

    PubMed Central

    Hartenstein, Volker; Takashima, Shigeo; Adams, Katrina

    2014-01-01

    The midgut epithelium is formed by absorptive enterocytes, secretory cells and endocrine cells. Each of these lineages is derived from the pluripotent progenitors that constitute the embryonic endoderm; the mature midgut retains pools of self-renewing stem cells that continue to produce all lineages. Recent findings in vertebrates and Drosophila shed light on the genetic mechanism that specifies the fate of the different lineages. A pivotal role is played by the Notch signaling pathway that, in a manner that appears to be very similar to the way in which Notch signaling selects neural progenitors within the neurectoderm, distinguishes the fate of secretory/endocrine cells and enterocytes. Proneural genes encoding bHLH transcription factors are expressed and required in prospective endocrine cells; activation of the Notch pathways restricts the number of these cells and promotes enterocyte development. In this review we compare the development of the intestinal endocrine cells in vertebrates and insects and summarize recent findings dealing with genetic pathways controlling this cell type. PMID:20005229

  1. Notch Promotes Dynamin-Dependent Endocytosis of Nephrin

    PubMed Central

    Waters, Aoife M.; Wu, Megan Yi Jun; Huang, Yi-Wei; Liu, Guang Ying; Holmyard, Doug; Onay, Tuncer; Jones, Nina; Egan, Sean E.; Robinson, Lisa A.

    2012-01-01

    Notch signaling in podocytes causes proteinuria and glomerulosclerosis in humans and rodents, but the underlying mechanism remains unknown. Here, we analyzed morphologic, molecular, and cellular events before the onset of proteinuria in newborn transgenic mice that express activated Notch in podocytes. Immunohistochemistry revealed a loss of the slit diaphragm protein nephrin exclusively in podocytes expressing activated Notch. Podocyte-specific deletion of Rbpj, which is essential for canonical Notch signaling, prevented this loss of nephrin. Overexpression of activated Notch decreased cell surface nephrin and increased cytoplasmic nephrin in transfected HEK293T cells; pharmacologic inhibition of dynamin, but not depletion of cholesterol, blocked these effects on nephrin, suggesting that Notch promotes dynamin-dependent, raft-independent endocytosis of nephrin. Supporting an association between Notch signaling and nephrin trafficking, electron microscopy revealed shortened podocyte foot processes and fewer slit diaphragms among the transgenic mice compared with controls. These data suggest that Notch signaling induces endocytosis of nephrin, thereby triggering the onset of proteinuria. PMID:22052054

  2. A small molecule targeting ALK1 prevents Notch cooperativity and inhibits functional angiogenesis.

    PubMed

    Kerr, Georgina; Sheldon, Helen; Chaikuad, Apirat; Alfano, Ivan; von Delft, Frank; Bullock, Alex N; Harris, Adrian L

    2015-04-01

    Activin receptor-like kinase 1 (ALK1, encoded by the gene ACVRL1) is a type I BMP/TGF-β receptor that mediates signalling in endothelial cells via phosphorylation of SMAD1/5/8. During angiogenesis, sprouting endothelial cells specialise into tip cells and stalk cells. ALK1 synergises with Notch in stalk cells to induce expression of the Notch targets HEY1 and HEY2 and thereby represses tip cell formation and angiogenic sprouting. The ALK1-Fc soluble protein fusion has entered clinic trials as a therapeutic strategy to sequester the high-affinity extracellular ligand BMP9. Here, we determined the crystal structure of the ALK1 intracellular kinase domain and explored the effects of a small molecule kinase inhibitor K02288 on angiogenesis. K02288 inhibited BMP9-induced phosphorylation of SMAD1/5/8 in human umbilical vein endothelial cells to reduce both the SMAD and the Notch-dependent transcriptional responses. In endothelial sprouting assays, K02288 treatment induced a hypersprouting phenotype reminiscent of Notch inhibition. Furthermore, K02288 caused dysfunctional vessel formation in a chick chorioallantoic membrane assay of angiogenesis. Such activity may be advantageous for small molecule inhibitors currently in preclinical development for specific BMP gain of function conditions, including diffuse intrinsic pontine glioma and fibrodysplasia ossificans progressiva, as well as more generally for other applications in tumour biology.

  3. γ-Secretase Inhibition Induces Muscle Hypertrophy in a Notch-Independent Mechanism.

    PubMed

    Rosa de Andrade, Ivone; Corrêa, Stephany; Fontenele, Marcio; de Oliveira Teixeira, John Douglas; Abdelhay, Eliana; Costa, Manoel Luis; Mermelstein, Claudia

    2018-02-01

    A wide variety of cellular processes and signaling events are regulated by the proteolytic enzyme γ-secretase. Notch-1 is one of the substrates of γ-secretase and its role in the regulation of muscle differentiation has been well described. Importantly, besides Notch-1, a number of proteins have been identified to undergo proteolysis by γ-secretase. To date, the specific role of γ-secretase during embryonic skeletal muscle differentiation has not been studied. Therefore, we address this question through the analysis of in vitro grown chick myogenic cells during the formation of multinucleated myotubes. The γ-secretase inhibitor DAPT (N-N[-(3,5-Difluorophenacetyl-l-alanyl)]-S-328 phenylglycine-t-butyl-ester) induces muscle hypertrophy. Knockdown of Notch-1 using siRNA specific to chick shows no significant effect in myotube size, suggesting that γ-secretase-dependent effects on muscle hypertrophy in chick myogenic cells are Notch-1-independent. We also investigate the effects of γ-secretase inhibition in the whole proteomic profile of chick myogenic cells. We identified 276 differentially expressed proteins from Label-free proteomic approach. Data overview of interaction network obtained from STRING show that after γ-secretase inhibition cells exhibited imbalance in protein metabolism, cytoskeleton/adhesion, and Sonic Hedgehog signaling. The collection of these results provides new insights into the role of γ-secretase in skeletal muscle hypertrophy. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Structural basis for Notch1 engagement of Delta-like 4

    DOE PAGES

    Luca, Vincent C.; Jude, Kevin M.; Pierce, Nathan W.; ...

    2015-02-20

    Notch receptors guide mammalian cell fate decisions by engaging the proteins Jagged and Delta-like (DLL). The 2.3 angstrom resolution crystal structure of the interacting regions of the Notch1-DLL4 complex reveals a two-site, antiparallel binding orientation assisted by Notch1 O-linked glycosylation. Notch1 epidermal growth factor–like repeats 11 and 12 interact with the DLL4 Delta/Serrate/Lag-2 (DSL) domain and module at the N-terminus of Notch ligands (MNNL) domains, respectively. Threonine and serine residues on Notch1 are functionalized with O-fucose and O-glucose, which act as surrogate amino acids by making specific, and essential, contacts to residues on DLL4. Lastly, the elucidation of a directmore » chemical role for O-glycans in Notch1 ligand engagement demonstrates how, by relying on posttranslational modifications of their ligand binding sites, Notch proteins have linked their functional capacity to developmentally regulated biosynthetic pathways.« less

  5. Structural basis for Notch1 engagement of Delta-like 4

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Luca, Vincent C.; Jude, Kevin M.; Pierce, Nathan W.

    Notch receptors guide mammalian cell fate decisions by engaging the proteins Jagged and Delta-like (DLL). The 2.3 angstrom resolution crystal structure of the interacting regions of the Notch1-DLL4 complex reveals a two-site, antiparallel binding orientation assisted by Notch1 O-linked glycosylation. Notch1 epidermal growth factor–like repeats 11 and 12 interact with the DLL4 Delta/Serrate/Lag-2 (DSL) domain and module at the N-terminus of Notch ligands (MNNL) domains, respectively. Threonine and serine residues on Notch1 are functionalized with O-fucose and O-glucose, which act as surrogate amino acids by making specific, and essential, contacts to residues on DLL4. Lastly, the elucidation of a directmore » chemical role for O-glycans in Notch1 ligand engagement demonstrates how, by relying on posttranslational modifications of their ligand binding sites, Notch proteins have linked their functional capacity to developmentally regulated biosynthetic pathways.« less

  6. FOXA1 promotes tumor cell proliferation through AR involving the Notch pathway in endometrial cancer

    PubMed Central

    2014-01-01

    Background Increasing evidence suggests that forkhead box A1 (FOXA1) is frequently dysregulated in many types of human cancers. However, the exact function and mechanism of FOXA1 in human endometrial cancer (EC) remains unclear. Methods FOXA1 expression, androgen receptor (AR) expression, and the relationships of these two markers with clinicopathological factors were determined by immunohistochemistry analysis. FOXA1 and AR were up-regulated by transient transfection with plasmids, and were down-regulated by transfection with siRNA or short hairpin RNA (shRNA). The effects of FOXA1 depletion and FOXA1 overexpression on AR-mediated transcription as well as Notch pathway and their impact on EC cell proliferation were examined by qRT-PCR, western blotting, co-immunoprecipitation, ChIP-PCR, MTT, colony-formation, and xenograft tumor–formation assays. Results We found that the expression of FOXA1 and AR in ECs was significantly higher than that in a typical hyperplasia and normal tissues. FOXA1 expression was significantly correlated with AR expression in clinical tissues. High FOXA1 levels positively correlated with pathological grade and depth of myometrial invasion in EC. High AR levels also positively correlated with pathological grade in EC. Moreover, the expression of XBP1, MYC, ZBTB16, and UHRF1, which are downstream targets of AR, was promoted by FOXA1 up-regulation or inhibited by FOXA1 down-regulation. Co-immunoprecipitation showed that FOXA1 interacted with AR in EC cells. ChIP-PCR assays showed that FOXA1 and AR could directly bind to the promoter and enhancer regions upstream of MYC. Mechanistic investigation revealed that over-expression of Notch1 and Hes1 proteins by FOXA1 could be reversed by AR depletion. In addition, we showed that down-regulation of AR attenuated FOXA1-up-regulated cell proliferation. However, AR didn’t influence the promotion effect of FOXA1 on cell migration and invasion. In vivo xenograft model, FOXA1 knockdown reduced the rate of tumor growth. Conclusions These results suggest that FOXA1 promotes cell proliferation by AR and activates Notch pathway. It indicated that FOXA1 and AR may serve as potential gene therapy in EC. PMID:24512546

  7. MicroRNA-34a targets epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs) and inhibits breast cancer cell migration and invasion

    PubMed Central

    Fu, Shangyi; Yang, Luquan; Tania, Mousumi; Zhang, Xianqin; Xiao, Xiuli; Zhang, Xianning; Fu, Junjiang

    2017-01-01

    MicroRNA-34a (miR-34a) plays an essential role against tumorigenesis and progression of cancer metastasis. Here, we analyzed the expression, targets and functional effects of miR-34a on epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs), such as TWIST1, SLUG and ZEB1/2, and an EMT-inducing protein NOTCH1 in breast cancer (BC) cell migration and invasion and its correlation with tumorigenesis and clinical outcomes. Expression of miR-34a is downregulated in human metastatic breast cancers (MBC) compared to normal breast tissues and is negatively correlated with clinicopathological features of MBC patients. Ectopic expression of miR-34a in MBC cell-line BT-549 significantly inhibits cell migration and invasion, but exhibits no clear effect on BC cell growth. We found that miR-34a is able to inactivate EMT signaling pathway with mediatory of NOTCH1, TWIST1, and ZEB1 upon 3′-UTR activity in MBC cell lines, but has no inhibitory effects on SLUG and ZEB2. Furthermore, we investigated the synergistic effects of Thymoquinone (TQ) and miR-34a together on the expression of EMT-associated proteins. Results showed that co-delivery of miR-34a and TQ is able to inactivate EMT signaling pathway by directly targeting TWIST1 and ZEB1 in BT-549 cell line, indicating that they might be a promising therapeutic combination against breast cancer metastasis. Epigenetic inactivation of the EMT-TFs/miR-34a pathway can potentially alter the equilibrium of these regulations, facilitating EMT and metastasis in BC. Altogether, our findings suggest that miR-34a alone could serve as a potential therapeutic agent for MBC, and together with TQ, their therapeutic potential is synergistically enhanced. PMID:28423483

  8. MicroRNA-34a targets epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs) and inhibits breast cancer cell migration and invasion.

    PubMed

    Imani, Saber; Wei, Chunli; Cheng, Jingliang; Khan, Md Asaduzzaman; Fu, Shangyi; Yang, Luquan; Tania, Mousumi; Zhang, Xianqin; Xiao, Xiuli; Zhang, Xianning; Fu, Junjiang

    2017-03-28

    MicroRNA-34a (miR-34a) plays an essential role against tumorigenesis and progression of cancer metastasis. Here, we analyzed the expression, targets and functional effects of miR-34a on epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs), such as TWIST1, SLUG and ZEB1/2, and an EMT-inducing protein NOTCH1 in breast cancer (BC) cell migration and invasion and its correlation with tumorigenesis and clinical outcomes. Expression of miR-34a is downregulated in human metastatic breast cancers (MBC) compared to normal breast tissues and is negatively correlated with clinicopathological features of MBC patients. Ectopic expression of miR-34a in MBC cell-line BT-549 significantly inhibits cell migration and invasion, but exhibits no clear effect on BC cell growth. We found that miR-34a is able to inactivate EMT signaling pathway with mediatory of NOTCH1, TWIST1, and ZEB1 upon 3'-UTR activity in MBC cell lines, but has no inhibitory effects on SLUG and ZEB2. Furthermore, we investigated the synergistic effects of Thymoquinone (TQ) and miR-34a together on the expression of EMT-associated proteins. Results showed that co-delivery of miR-34a and TQ is able to inactivate EMT signaling pathway by directly targeting TWIST1 and ZEB1 in BT-549 cell line, indicating that they might be a promising therapeutic combination against breast cancer metastasis. Epigenetic inactivation of the EMT-TFs/miR-34a pathway can potentially alter the equilibrium of these regulations, facilitating EMT and metastasis in BC. Altogether, our findings suggest that miR-34a alone could serve as a potential therapeutic agent for MBC, and together with TQ, their therapeutic potential is synergistically enhanced.

  9. Mind bomb-1 is an essential modulator of long-term memory and synaptic plasticity via the Notch signaling pathway

    PubMed Central

    2012-01-01

    Background Notch signaling is well recognized as a key regulator of the neuronal fate during embryonic development, but its function in the adult brain is still largely unknown. Mind bomb-1 (Mib1) is an essential positive regulator in the Notch pathway, acting non-autonomously in the signal-sending cells. Therefore, genetic ablation of Mib1 in mature neuron would give valuable insight to understand the cell-to-cell interaction between neurons via Notch signaling for their proper function. Results Here we show that the inactivation of Mib1 in mature neurons in forebrain results in impaired hippocampal dependent spatial memory and contextual fear memory. Consistently, hippocampal slices from Mib1-deficient mice show impaired late-phase, but not early-phase, long-term potentiation and long-term depression without change in basal synaptic transmission at SC-CA1 synapses. Conclusions These data suggest that Mib1-mediated Notch signaling is essential for long-lasting synaptic plasticity and memory formation in the rodent hippocampus. PMID:23111145

  10. Notch3 is necessary for neuronal differentiation and maturation in the adult spinal cord

    PubMed Central

    Rusanescu, Gabriel; Mao, Jianren

    2014-01-01

    Notch receptors are key regulators of nervous system development and promoters of neural stem cells renewal and proliferation. Defects in the expression of Notch genes result in severe, often lethal developmental abnormalities. Notch3 is generally thought to have a similar proliferative, anti-differentiation and gliogenic role to Notch1. However, in some cases, Notch3 has an opposite, pro-differentiation effect. Here, we show that Notch3 segregates from Notch1 and is transiently expressed in adult rat and mouse spinal cord neuron precursors and immature neurons. This suggests that during the differentiation of adult neural progenitor cells, Notch signalling may follow a modified version of the classical lateral inhibition model, involving the segregation of individual Notch receptors. Notch3 knockout mice, otherwise neurologically normal, are characterized by a reduced number of mature inhibitory interneurons and an increased number of highly excitable immature neurons in spinal cord laminae I–II. As a result, these mice have permanently lower nociceptive thresholds, similar to chronic pain. These results suggest that defective neuronal differentiation, for example as a result of reduced Notch3 expression or activation, may underlie human cases of intractable chronic pain, such as fibromyalgia and neuropathic pain. PMID:25164209

  11. Jagged-1 Signaling Pathway in Prostate Cancer Cell Growth and Angiogenesis

    DTIC Science & Technology

    2010-04-01

    18 . NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON a. REPORT b. ABSTRACT c. THIS PAGE 80 19b. TELEPHONE... LN Ca P C4 -2 B M DA P Ca 2B Notch-2 Notch-1 Notch-4 Notch-3 β-actin Jagged-1 PC -3 DU 14 5 LN Ca P C4 -2 B M DA P Ca 2B β-actin Jagged-2 DLL-4 DLL-1...frequently up-regulated in most human malignancies including lung cancer, glioblastomas , PCa, basal cell carcinomas, hepatocellular carcinoma,

  12. Evidence for the Induction of Key Components of the NOTCH Signaling Pathway via Deltamethrin and Azamethiphos Treatment in the Sea Louse Caligus rogercresseyi

    PubMed Central

    Boltaña, Sebastian; Chávez-Mardones, Jaqueline; Valenzuela-Muñoz, Valentina; Gallardo-Escárate, Cristian

    2016-01-01

    The extensive use of organophosphates and pyrethroids in the aquaculture industry has negatively impacted parasite sensitivity to the delousing effects of these antiparasitics, especially among sea lice species. The NOTCH signaling pathway is a positive regulator of ABC transporter subfamily C expression and plays a key role in the generation and modulation of pesticide resistance. However, little is known about the molecular mechanisms behind pesticide resistance, partly due to the lack of genomic and molecular information on the processes involved in the resistance mechanism of sea lice. Next-generation sequencing technologies provide an opportunity for rapid and cost-effective generation of genome-scale data. The present study, through RNA-seq analysis, determined that the sea louse Caligus rogercresseyi (C. rogercresseyi) specifically responds to the delousing drugs azamethiphos and deltamethrin at the transcriptomic level by differentially activating mRNA of the NOTCH signaling pathway and of ABC genes. These results suggest that frequent antiparasitic application may increase the activity of inhibitory mRNA components, thereby promoting inhibitory NOTCH output and conditions for increased resistance to delousing drugs. Moreover, data analysis underscored that key functions of NOTCH/ABC components were regulated during distinct phases of the drug response, thus indicating resistance modifications in C. rogercresseyi resulting from the frequent use of organophosphates and pyrethroids. PMID:27187362

  13. Evidence for the Induction of Key Components of the NOTCH Signaling Pathway via Deltamethrin and Azamethiphos Treatment in the Sea Louse Caligus rogercresseyi.

    PubMed

    Boltaña, Sebastian; Chávez-Mardones, Jaqueline; Valenzuela-Muñoz, Valentina; Gallardo-Escárate, Cristian

    2016-05-12

    The extensive use of organophosphates and pyrethroids in the aquaculture industry has negatively impacted parasite sensitivity to the delousing effects of these antiparasitics, especially among sea lice species. The NOTCH signaling pathway is a positive regulator of ABC transporter subfamily C expression and plays a key role in the generation and modulation of pesticide resistance. However, little is known about the molecular mechanisms behind pesticide resistance, partly due to the lack of genomic and molecular information on the processes involved in the resistance mechanism of sea lice. Next-generation sequencing technologies provide an opportunity for rapid and cost-effective generation of genome-scale data. The present study, through RNA-seq analysis, determined that the sea louse Caligus rogercresseyi (C. rogercresseyi) specifically responds to the delousing drugs azamethiphos and deltamethrin at the transcriptomic level by differentially activating mRNA of the NOTCH signaling pathway and of ABC genes. These results suggest that frequent antiparasitic application may increase the activity of inhibitory mRNA components, thereby promoting inhibitory NOTCH output and conditions for increased resistance to delousing drugs. Moreover, data analysis underscored that key functions of NOTCH/ABC components were regulated during distinct phases of the drug response, thus indicating resistance modifications in C. rogercresseyi resulting from the frequent use of organophosphates and pyrethroids.

  14. Prognostic Subcellular Notch2, Notch3 and Jagged1 Localization Patterns in Early Triple-negative Breast Cancer.

    PubMed

    Strati, Titika-Marina; Kotoula, Vassiliki; Kostopoulos, Ioannis; Manousou, Kyriaki; Papadimitriou, Christos; Lazaridis, Georgios; Lakis, Sotiris; Pentheroudakis, George; Pectasides, Dimitrios; Pazarli, Elissavet; Christodoulou, Christos; Razis, Evangelia; Pavlakis, Kitty; Magkou, Christina; Chrisafi, Sofia; Aravantinos, Gerasimos; Bafaloukos, Dimitrios; Papakostas, Pavlos; Gogas, Helen; Kalogeras, Konstantine T; Fountzilas, George

    2017-05-01

    The Notch pathway has been implicated in triple-negative breast cancer (TNBC). Herein, we studied the subcellular localization of the less investigated Notch2 and Notch3 and that of the Jagged1 (Jag1) ligand in patients with operable TNBC. We applied immunohistochemistry for Notch2, Notch3 and Jag1 in 333 tumors from TNBC patients treated with adjuvant anthracycline-based chemotherapy. We evaluated cytoplasmic (c), membranous (m) and nuclear (n) protein localization. c-Notch2 (35% positive tumors), c-Notch3 (63%), c-Jag1 (43%), m-Notch3 (23%) and n-Jag1 (17%) were analyzed individually and by using hierarchical clustering for prognostic evaluation. Upon multivariate analysis, compared to high m-Notch3 in the absence of n-Jag1 (cluster 4), all other marker combinations (clusters 1, 2, 3) conferred significantly higher risk for relapse (p<0.05). Specific Notch3 and Jag1 subcellular localization patterns may provide clues for the behavior of the tumors and potentially for Jag1 targeting in TNBC patients. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  15. RNA interference-mediated NOTCH3 knockdown induces phenotype switching of vascular smooth muscle cells in vitro

    PubMed Central

    Liu, Nan; Li, Ying; Chen, Hui; Wei, Wei; An, Yulin; Zhu, Guangming

    2015-01-01

    Notch3 plays an important role in differentiation, migration and signal transduction of vascular smooth muscle cells (VSMCs). In this study, we used RNA interference (RNAi) technique to investigate the effect of knocking down the expression of the NOTCH3 gene in VSMCs on the phenotype determination under pathologic status. Real-time PCR and Western Blot experiments verified the expression levels of Notch3 mRNA and protein were reduced more than 40% and 50% in the NOTCH3 siRNA group. When the expression of Notch3 was decreased, the proliferation, apoptosis and immigration of VSMCs were enhanced compared to control groups (P < 0.01). NOTCH3 siRNA VSMCs observed using confocal microscopy showed abnormal nuclear configuration, a disorganized actin filament system, polygonal cell shapes, and decreasing cell sizes. Additionally, knocking down the expression of NOTCH3 may evoke the CASR and FAK expression. In Conclusion, interfering with the expression of NOTCH3 causes VSMCs to exhibit an intermediate phenotype. CaSR and FAK may be involved in the Notch3 signaling pathway. PMID:26550181

  16. RNA interference-mediated NOTCH3 knockdown induces phenotype switching of vascular smooth muscle cells in vitro.

    PubMed

    Liu, Nan; Li, Ying; Chen, Hui; Wei, Wei; An, Yulin; Zhu, Guangming

    2015-01-01

    Notch3 plays an important role in differentiation, migration and signal transduction of vascular smooth muscle cells (VSMCs). In this study, we used RNA interference (RNAi) technique to investigate the effect of knocking down the expression of the NOTCH3 gene in VSMCs on the phenotype determination under pathologic status. Real-time PCR and Western Blot experiments verified the expression levels of Notch3 mRNA and protein were reduced more than 40% and 50% in the NOTCH3 siRNA group. When the expression of Notch3 was decreased, the proliferation, apoptosis and immigration of VSMCs were enhanced compared to control groups (P < 0.01). NOTCH3 siRNA VSMCs observed using confocal microscopy showed abnormal nuclear configuration, a disorganized actin filament system, polygonal cell shapes, and decreasing cell sizes. Additionally, knocking down the expression of NOTCH3 may evoke the CASR and FAK expression. In Conclusion, interfering with the expression of NOTCH3 causes VSMCs to exhibit an intermediate phenotype. CaSR and FAK may be involved in the Notch3 signaling pathway.

  17. Zeb2 recruits HDAC-NuRD to inhibit Notch and controls Schwann cell differentiation and remyelination.

    PubMed

    Wu, Lai Man Natalie; Wang, Jincheng; Conidi, Andrea; Zhao, Chuntao; Wang, Haibo; Ford, Zachary; Zhang, Liguo; Zweier, Christiane; Ayee, Brian G; Maurel, Patrice; Zwijsen, An; Chan, Jonah R; Jankowski, Michael P; Huylebroeck, Danny; Lu, Q Richard

    2016-08-01

    The mechanisms that coordinate and balance a complex network of opposing regulators to control Schwann cell (SC) differentiation remain elusive. Here we demonstrate that zinc-finger E-box-binding homeobox 2 (Zeb2, also called Sip1) transcription factor is a critical intrinsic timer that controls the onset of SC differentiation by recruiting histone deacetylases HDAC 1 and 2 (HDAC1/2) and nucleosome remodeling and deacetylase complex (NuRD) co-repressor complexes in mice. Zeb2 deletion arrests SCs at an undifferentiated state during peripheral nerve development and inhibits remyelination after injury. Zeb2 antagonizes inhibitory effectors including Notch and Sox2. Importantly, genome-wide transcriptome analysis reveals a Zeb2 target gene encoding the Notch effector Hey2 as a potent inhibitor for Schwann cell differentiation. Strikingly, a genetic Zeb2 variant associated with Mowat-Wilson syndrome disrupts the interaction with HDAC1/2-NuRD and abolishes Zeb2 activity for SC differentiation. Therefore, Zeb2 controls SC maturation by recruiting HDAC1/2-NuRD complexes and inhibiting a Notch-Hey2 signaling axis, pointing to the critical role of HDAC1/2-NuRD activity in peripheral neuropathies caused by ZEB2 mutations.

  18. Regulation of broad by the Notch pathway affects timing of follicle cell development

    PubMed Central

    Jia, Dongyu; Tamori, Yoichiro; Pyrowolakis, George; Deng, Wu-Min

    2014-01-01

    During Drosophila oogenesis, activation of Notch signaling in the follicular epithelium (FE) around stage 6 of oogenesis is essential for entry into the endocycle and a series of other changes such as cell differentiation and migration of subsets of the follicle cells. Notch induces the expression of zinc finger protein Hindsight and suppresses homeodomain protein Cut to regulate the mitotic/endocycle (ME) switch. Here we report that broad (br), encoding a small group of zinc-finger transcription factors resulting from alternative splicing, is a transcriptional target of Notch nuclear effector Suppressor of Hairless (Su(H)). The early pattern of Br in the FE, uniformly expressed except in the polar cells, is established by Notch signaling around stage 6, through the binding of Su(H) to the br early enhancer (brE) region. Mutation of the Su(H) binding site leads to a significant reduction of brE reporter expression in follicle cells undergoing the endocycle. Chromatin immunoprecipitation results further confirm Su(H) binding to the br early enhancer. Consistent with its expression in follicle cells during midoogenesis, loss of br function results in a delayed entry into the endocycle. Our findings suggest an important role of br in the timing of follicle cell development, and its transcriptional regulation by the Notch pathway. PMID:24815210

  19. The NOTCH Ligand JAG1 Regulates GDNF Expression in Sertoli Cells

    PubMed Central

    Garcia, Thomas X.; Parekh, Parag; Gandhi, Pooja; Sinha, Krishna

    2017-01-01

    In the seminiferous epithelium of the testis, Sertoli cells are key niche cells directing proliferation and differentiation of spermatogonial stem cells (SSCs) into spermatozoa. Sertoli cells produce glial cell line-derived neurotrophic factor (GDNF), which is essential for SSC self-renewal and progenitor expansion. While the role of GDNF in the testis stem cell niche is established, little is known about how this factor is regulated. Our previous studies on NOTCH activity in Sertoli cells demonstrated a role of this pathway in limiting stem/progenitor cell numbers, thus ultimately downregulating sperm cell output. In this study we demonstrate through a double-mutant mouse model that NOTCH signaling in Sertoli cells functions solely through the canonical pathway. Further, we demonstrate through Dual luciferase assay and chromatin immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR) analysis that the NOTCH targets HES1 and HEY1, which are transcriptional repressors, directly downregulate GDNF expression by binding to the Gdnf promoter, thus antagonizing the effects of FSH/cAMP. Finally, we demonstrate that testicular stem/progenitors cells are activating NOTCH signaling in Sertoli cells in vivo and in vitro through the NOTCH ligand JAG1 at their surface, indicating that these cells may ensure their own homeostasis through negative feedback regulation. PMID:28051360

  20. Characteristics of the pulse waveform during altered nitric oxide synthesis in the rabbit.

    PubMed

    Weinberg, P D; Habens, F; Kengatharan, M; Barnes, S E; Matz, J; Anggård, E E; Carrier, M J

    2001-06-01

    Nitrovasodilators produce characteristic changes in the shape of the peripheral pulse wave. Similar changes might also be caused by alteration of endogenous NO activity, which would allow such activity to be assessed in vivo. We investigated whether manipulation of the NO pathway influences the pulse waveform, and the mechanisms involved. The pulse wave in the ear of normal rabbits was examined by reflectance photoplethysmography before and during infusion of vasoactive agents. Pulse wave velocity was assessed by using an additional sensor on the rear foot. A diastolic peak was observed in the ear pulse; its timing was consistent with it being a reflection of the systolic peak from the lower body. The height of the dicrotic notch marking the start of this diastolic wave was decreased by acetylcholine or an NO donor, and further decreased by a phosphodiesterase type V inhibitor. The acetylcholine-induced decreases were blocked by inhibiting NO synthesis with N(G)-nitro-L-arginine methyl ester (L-NAME) but were unaffected by the inactive enantiomer D-NAME. These data demonstrate that NO influences the height of the notch in the pulse wave. Heart rate and blood pressure were altered during acetylcholine or L-NAME infusion, but there were no changes in pulse wave amplitude or velocity, or in the timing of the diastolic peak or dicrotic notch. The slope of the pulse wave between the systolic peak and notch changed substantially. These effects are most convincingly explained by changes in wave reflection, not only from the lower body but also from more proximal sites.

  1. Characteristics of the pulse waveform during altered nitric oxide synthesis in the rabbit

    PubMed Central

    Weinberg, P D; Habens, F; Kengatharan, M; Barnes, S E; Matz, J; Änggård, E E; Carrier, M J

    2001-01-01

    Nitrovasodilators produce characteristic changes in the shape of the peripheral pulse wave. Similar changes might also be caused by alteration of endogenous NO activity, which would allow such activity to be assessed in vivo. We investigated whether manipulation of the NO pathway influences the pulse waveform, and the mechanisms involved. The pulse wave in the ear of normal rabbits was examined by reflectance photoplethysmography before and during infusion of vasoactive agents. Pulse wave velocity was assessed by using an additional sensor on the rear foot. A diastolic peak was observed in the ear pulse; its timing was consistent with it being a reflection of the systolic peak from the lower body. The height of the dicrotic notch marking the start of this diastolic wave was decreased by acetylcholine or an NO donor, and further decreased by a phosphodiesterase type V inhibitor. The acetylcholine-induced decreases were blocked by inhibiting NO synthesis with NG-nitro-L-arginine methyl ester (L-NAME) but were unaffected by the inactive enantiomer D-NAME. These data demonstrate that NO influences the height of the notch in the pulse wave. Heart rate and blood pressure were altered during acetylcholine or L-NAME infusion, but there were no changes in pulse wave amplitude or velocity, or in the timing of the diastolic peak or dicrotic notch. The slope of the pulse wave between the systolic peak and notch changed substantially. These effects are most convincingly explained by changes in wave reflection, not only from the lower body but also from more proximal sites. PMID:11375252

  2. The pathological significance of Notch1 in oral squamous cell carcinoma.

    PubMed

    Yoshida, Ryoji; Nagata, Masashi; Nakayama, Hideki; Niimori-Kita, Kanako; Hassan, Wael; Tanaka, Takuji; Shinohara, Masanori; Ito, Takaaki

    2013-10-01

    Notch signaling has been reported to be involved in several types of malignant tumors; however, the role and activation mechanism of Notch signaling in oral squamous cell carcinoma (OSCC) remains poorly characterized. The purpose of this study was to elucidate the pathological significance of Notch signaling and its activation mechanism in the development and progression of OSCC. In this study, we showed that the expression of Notch1 and intracellular Notch domain (NICD) are upregulated in OSCCs. In addition, Notch1 and NICD were found to be characteristically localized at the invasive tumor front. TNF-α, a major inflammatory cytokine, significantly activated Notch signaling in vitro. In a clinicopathological analysis, Notch1 expression correlated with both the T-stage and the clinical stage. Furthermore, loss of Notch1 expression correlated with the inhibition of cell proliferation and TNF-α-dependent invasiveness in an OSCC cell line. In addition, γ-secretase inhibitor (GSI) prevented cell proliferation and TNF-α-dependent invasion of OSCC cells in vitro. These results indicate that altered expression of Notch1 is associated with increased cancer progression and that Notch1 regulates the steps involved in cell metastasis in OSCC. Moreover, inactivating Notch signaling with GSI could therefore be a useful approach for treating patients with OSCC.

  3. Loss of Notch3 Signaling in Vascular Smooth Muscle Cells Promotes Severe Heart Failure Upon Hypertension.

    PubMed

    Ragot, Hélène; Monfort, Astrid; Baudet, Mathilde; Azibani, Fériel; Fazal, Loubina; Merval, Régine; Polidano, Evelyne; Cohen-Solal, Alain; Delcayre, Claude; Vodovar, Nicolas; Chatziantoniou, Christos; Samuel, Jane-Lise

    2016-08-01

    Hypertension, which is a risk factor of heart failure, provokes adaptive changes at the vasculature and cardiac levels. Notch3 signaling plays an important role in resistance arteries by controlling the maturation of vascular smooth muscle cells. Notch3 deletion is protective in pulmonary hypertension while deleterious in arterial hypertension. Although this latter phenotype was attributed to renal and cardiac alterations, the underlying mechanisms remained unknown. To investigate the role of Notch3 signaling in the cardiac adaptation to hypertension, we used mice with either constitutive Notch3 or smooth muscle cell-specific conditional RBPJκ knockout. At baseline, both genotypes exhibited a cardiac arteriolar rarefaction associated with oxidative stress. In response to angiotensin II-induced hypertension, the heart of Notch3 knockout and SM-RBPJκ knockout mice did not adapt to pressure overload and developed heart failure, which could lead to an early and fatal acute decompensation of heart failure. This cardiac maladaptation was characterized by an absence of media hypertrophy of the media arteries, the transition of smooth muscle cells toward a synthetic phenotype, and an alteration of angiogenic pathways. A subset of mice exhibited an early fatal acute decompensated heart failure, in which the same alterations were observed, although in a more rapid timeframe. Altogether, these observations indicate that Notch3 plays a major role in coronary adaptation to pressure overload. These data also show that the hypertrophy of coronary arterial media on pressure overload is mandatory to initially maintain a normal cardiac function and is regulated by the Notch3/RBPJκ pathway. © 2016 American Heart Association, Inc.

  4. Constitutive activation of NOTCH1 signaling in Sertoli cells causes gonocyte exit from quiescence

    PubMed Central

    Garcia, Thomas Xavier; DeFalco, Tony; Capel, Blanche; Hofmann, Marie-Claude

    2013-01-01

    Notch signaling components have long been detected in Sertoli and germ cells in the developing and mature testis. However, the role of this pathway in testis development and spermatogenesis remains unknown. Using reporter mice expressing green fluorescent protein following Notch receptor activation, we found that Notch signaling was active in Sertoli cells at various fetal, neonatal, and adult stages. Since Notch signaling specifies stem cell fate in many developing and mature organ systems, we hypothesized that maintenance and differentiation of gonocytes and/or spermatogonial stem cells would be modulated through this pathway in Sertoli cells. To this end, we generated mutant mice constitutively expressing the active, intracellular domain of NOTCH1 (NICD1) in Sertoli cells. We found that mutant Sertoli cells were morphologically normal before and after birth, but presented a number of functional changes that drastically affected gonocyte numbers and physiology. We observed aberrant exit of gonocytes from mitotic arrest, migration toward cord periphery, and premature differentiation before birth. These events, presumably unsupported by the cellular microenvironment, were followed by gonocyte apoptosis and near complete disappearance of the gonocytes by day 2 after birth. Molecular analysis demonstrated that these effects are correlated with a dysregulation of Sertoli-expressed genes that are required for germ cell maintenance, such as Cyp26b1 and Gdnf. Taken together, our results demonstrate that Notch signaling is active in Sertoli cells throughout development and that proper regulation of Notch signaling in Sertoli cells is required for the maintenance of gonocytes in an undifferentiated state during fetal development. PMID:23391689

  5. IL-4/IL-13 Signaling Inhibits the Potential of Early Thymic Progenitors To Commit to the T Cell Lineage.

    PubMed

    Barik, Subhasis; Miller, Mindy M; Cattin-Roy, Alexis N; Ukah, Tobechukwu K; Chen, Weirong; Zaghouani, Habib

    2017-10-15

    Early thymic progenitors (ETPs) are endowed with diverse potencies and can give rise to myeloid and lymphoid lineage progenitors. How the thymic environment guides ETP commitment and maturation toward a specific lineage remains obscure. We have previously shown that ETPs expressing the heteroreceptor (HR) comprising IL-4Rα and IL-13Rα1 give rise to myeloid cells but not T cells. In this article, we show that signaling through the HR inhibits ETP maturation to the T cell lineage but enacts commitment toward the myeloid cells. Indeed, HR + ETPs, but not HR - ETPs, exhibit activated STAT6 transcription factor, which parallels with downregulation of Notch1, a critical factor for T cell development. Meanwhile, the myeloid-specific transcription factor C/EBPα, usually under the control of Notch1, is upregulated. Furthermore, in vivo inhibition of STAT6 phosphorylation restores Notch1 expression in HR + ETPs, which regain T lineage potential. In addition, upon stimulation with IL-4 or IL-13, HR - ETPs expressing virally transduced HR also exhibit STAT6 phosphorylation and downregulation of Notch1, leading to inhibition of lymphoid, but not myeloid, lineage potential. These observations indicate that environmental cytokines play a role in conditioning ETP lineage choice, which would impact T cell development. Copyright © 2017 by The American Association of Immunologists, Inc.

  6. Notch and affinity boundaries in Drosophila.

    PubMed

    Herranz, Héctor; Milán, Marco

    2006-02-01

    Cells in multicellular organisms often do not intermingle freely with each other. Differential cell affinities can contribute to organizing cells into different tissues. Drosophila limbs and the vertebrate central nervous system are subdivided into compartments. Cells in adjacent compartments do not mix. Cell interactions mediated by Notch-family receptors have been implicated in the specification of these compartment boundaries. Two recent reports analyze the role of the Notch signaling pathway in the generation of an affinity boundary in the Drosophila wing. The first report analyzes the connection between Notch and the actin cytoskeleton. The second report analyzes the differential requirements of Notch and the transcription factor Suppressor of Hairless in generating the affinity boundary.

  7. Altered epidermal growth factor-like sequences provide evidence for a role of Notch as a receptor in cell fate decisions.

    PubMed

    Heitzler, P; Simpson, P

    1993-03-01

    In Drosophila each neural precursor is chosen from a group of cells through cell interactions mediated by Notch and Delta which may function as receptor and ligand (signal), respectively, in a lateral signalling pathway. The cells of a group are equipotential and express both Notch and Delta. Hyperactive mutant Notch molecules, (Abruptex), probably have an enhanced affinity for the ligand. When adjacent to wild-type cells, cells bearing the Abruptex proteins are unable to produce the signal. It is suggested that in addition to the binding of Notch molecules on one cell to the Delta molecules of opposing cells, the Notch and Delta proteins on the surface of the same cell may interact. Binding between a cell's own Notch and Delta molecules would alter the availability of these proteins to interact with their counterparts on adjacent cells.

  8. Notch signaling genes

    PubMed Central

    Terragni, Jolyon; Zhang, Guoqiang; Sun, Zhiyi; Pradhan, Sriharsa; Song, Lingyun; Crawford, Gregory E; Lacey, Michelle; Ehrlich, Melanie

    2014-01-01

    Notch intercellular signaling is critical for diverse developmental pathways and for homeostasis in various types of stem cells and progenitor cells. Because Notch gene products need to be precisely regulated spatially and temporally, epigenetics is likely to help control expression of Notch signaling genes. Reduced representation bisulfite sequencing (RRBS) indicated significant hypomethylation in myoblasts, myotubes, and skeletal muscle vs. many nonmuscle samples at intragenic or intergenic regions of the following Notch receptor or ligand genes: NOTCH1, NOTCH2, JAG2, and DLL1. An enzymatic assay of sites in or near these genes revealed unusually high enrichment of 5-hydroxymethylcytosine (up to 81%) in skeletal muscle, heart, and cerebellum. Epigenetics studies and gene expression profiles suggest that hypomethylation and/or hydroxymethylation help control expression of these genes in heart, brain, myoblasts, myotubes, and within skeletal muscle myofibers. Such regulation could promote cell renewal, cell maintenance, homeostasis, and a poised state for repair of tissue damage. PMID:24670287

  9. COE inhibits vasculogenic mimicry in hepatocellular carcinoma via suppressing Notch1 signaling.

    PubMed

    Jue, Chen; Min, Zhao; Zhisheng, Zhang; Lin, Cui; Yayun, Qian; Xuanyi, Wang; Feng, Jin; Haibo, Wang; Youyang, Shi; Tadashi, Hisamitsu; Shintaro, Ishikawa; Shiyu, Guo; Yanqing, Liu

    2017-08-17

    Vasculogenic mimicry (VM) has been suggested to be present in various malignant tumors and associated with tumor nutrition supply and metastasis, leading to poor prognosis of patients. Notch1 has been demonstrated to contribute to VM formation in hepathocellular carcinoma (HCC). Celastrus orbiculatus extract (COE), a mixture of 11 terpenoids isolated from the Chinese Herb Celastrus orbiculatus Vine, has been suggested to be effective in cancer treatment. In the current study, experiments were carried out to examine the effect of COE on VM formation and HCC tumor growth both in vitro and in vivo. CCK-8 assay and Nikon live-work station were used to observe the viability of malignant cells treated with COE. Cell invasion was examined using Transwell. Matrigel was used to establish a 3-D culture condition for VM formation. Changes of mRNA and protein expression were examined by RT-PCR and Western Blot respectively. Tumor growth in vivo was monitored using in vivo fluorescence imaging device. PAS-CD34 dual staining and electron microscopy were used to observe VM formation. Immunohistochemical staining (IHC) was used to examine Notch1 and Hes1 expression in tumor tissues. Results showed that COE can inhibit HCC cells proliferation and invasion in a concentration-dependent manner. VM formation induced by TGF-β1 was blocked by COE. In mouse xenograft model, COE inhibited tumor growth and VM formation. Both in vitro and in vivo studies showed that COE can downregulate expression of Notch1 and Hes1. The current results indicate that COE can inhibit VM formation and HCC tumor growth by downregulating Notch1 signaling. This study demonstrates that COE is superior to other anti-angiogenesis agents and can be considered as a promising candidate in HCC treatment. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  10. Valproic acid exhibits different cell growth arrest effect in three HPV-positive/negative cervical cancer cells and possibly via inducing Notch1 cleavage and E6 downregulation.

    PubMed

    Feng, Shuyu; Yang, Yue; Lv, Jingyi; Sun, Lichun; Liu, Mingqiu

    2016-07-01

    We investigated the effect of valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, and the mechanism of VPA-induced growth inhibition on three cervical cancer cell lines with different molecular and genetic background. We found that VPA induced proliferation suppression, cell apoptosis and cell cycle arrest in all tested cell lines, with an increase of Notch1 active form ICN1 as a tumor suppressor and its target gene HES1. Noteworthy, blocking of Notch signaling with DAPT resulted in growth inhibition in ICN1-overexpressing CaSki and HT-3 cells. Thus, endogenous Notch signaling may be necessary for survival of ICN1-overexpressing cervical cancer cell lines. Furthermore, G1 phase arrest was induced in HeLa and CaSki cells by VPA while G2 phase arrest was induced in HT-3 cells, suggesting different mechanism in this cycle arrest. We also found VPA suppressed oncogene E6 in a Notch-independent manner, and induced significant apoptosis in E6-overexpressing HPV positive CaSki cells. Cell morphological change was also observed in HeLa and HT-3 cell lines after VPA treatment with an upregulation of EMT transcription factor Snail1. Notch signaling inhibitor DAPT partly reversed VPA-induced Snail1 upregulation in HeLa cells. This discovery supports that VPA may induce EMT at least partly via Notch activation.

  11. Notch Signaling in Prostate Cancer Cells Promotes Osteoblastic Metastasis

    DTIC Science & Technology

    2017-06-01

    in the tumor- bone microenvironment. Conversely, inhibition of Notch3 in PC3, 22rv1 and C42B cells with shRNA, promoted prostate cancer–induced...metastasis and thus may be a therapeutic target for such metastatic lesions. 15. SUBJECT TERMS Prostate Cancer; Notch3; MMP3; Bone -Tumor microenvironment...9 4 1. Introduction: To address the clinical problem of disease progression in prostate cancer- induced bone metastasis, the

  12. Effects of Notch2 and Notch3 on Cell Proliferation and Apoptosis of Trophoblast Cell Lines.

    PubMed

    Zhao, Wei-Xiu; Zhuang, Xu; Huang, Tao-Tao; Feng, Ran; Lin, Jian-Hua

    2015-01-01

    To investigate the effect of Notch2 and Notch3 on cell proliferation and apoptosis of two trophoblast cell lines, BeWo and JAR. Notch2 and Notch3 expression in BeWo and JAR cells was upregulated or downregulated using lentivirus-mediated overexpression or RNA interference. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. The effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V-PE Apoptosis kit. Lentivirus-based overexpression vectors were constructed by cloning the full-length coding sequences of human Notch2 and Notch3 C-terminally tagged with GFP or GFP alone (control) into a lentivirus-based expression vector. Lentivirus-based gene silencing vectors were prepared by cloning small interfering sequences targeting human Notch2 and Notch3 and scrambled control RNA sequence into a lentivirus-based gene knockdown vector. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. And the effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V PE Apoptosis kit. We found that the downregulation of Notch2 and Notch3 gene expression in BeWo and JAR cells resulted in an increase in cell proliferation, while upregulation of Notch3 and Notch2 expression led to a decrease in cell proliferation. Moreover, the overexpression of Notch3 and Notch2 in BeWo and JAR cells reduced apoptosis in these trophoblast cell lines, whereas apoptosis was increased in the cells in which the expression of Notch3 and Notch2 was downregulated. Notch2 and Notch3 inhibited both cell proliferation and cell apoptosis in BeWo and JAR trophoblast cell lines.

  13. Inhibition of NEDD4 inhibits cell growth and invasion and induces cell apoptosis in bladder cancer cells.

    PubMed

    Wen, Wu; Li, Jingying; Wang, Longwang; Xing, Yifei; Li, Xuechao; Ruan, Hailong; Xi, Xiaoqing; Xiong, Jianhua; Kuang, Renrui

    2017-08-18

    The neural precursor cell expressed developmentally downregulated protein 4 (NEDD4) plays a pivotal oncogenic role in various types of human cancers. However, the function of NEDD4 in bladder cancer has not been fully investigated. In the present study, we aim to explore whether NEDD4 governs cell proliferation, apoptosis, migration, and invasion in bladder cancer cells. Our results showed that downregulation of NEDD4 suppressed cell proliferation in bladder cancer cells. Moreover, we found that inhibition of NEDD4 significantly induced cell apoptosis. Furthermore, downregulation of NEDD4 retarded cell migration and invasion. Notably, overexpression of NEDD4 enhanced cell growth and inhibited apoptosis. Consistently, upregulation of NEDD4 promoted cell migration and invasion in bladder cancer cells. Mechanically, our Western blotting results revealed that downregulation of NEDD4 activated PTEN and inhibited Notch-1 expression, whereas upregulation of NEDD4 reduced PTEN level and increased Notch-1 level in bladder cancer cells. Our findings indicated that NEDD4 exerts its oncogenic function partly due to regulation of PTEN and Notch-1 in bladder cancer cells. These results further revealed that targeting NEDD4 could be a useful approach for the treatment of bladder cancer.

  14. Characterization of a new B-ALL cell line with constitutional defect of the Notch signaling pathway

    PubMed Central

    Kamga, Paul Takam; Dal Collo, Giada; Bassi, Giulio; Midolo, Martina; Delledonne, Massimo; Chilosi, Marco; Bonifacio, Massimiliano; Krampera, Mauro

    2018-01-01

    Notch signaling contribution to B-cell acute lymphoblastic leukemia (B-ALL) development is still under investigation. The serendipitous onset of B-ALL in a patient affected by the germinal Notch mutation-dependent Alagille syndrome allowed us to establish a B-ALL cell line (VR-ALL) bearing a genetic loss of function in components of Notch signaling. VR-ALL is a common-type B-ALL cell line, grows in conventional culture medium supplemented with 10% serum, and gives rise, once injected into immunodeficient NOG mice, to a mouse xenograft model of B-ALL. Exome sequencing revealed deleterious mutations in some components of Notch signaling, including Jagged1, Notch1, and Notch2. In addition, VR-ALL is sensitive both in vitro and in vivo to γ-secretase inhibitors (GSIs) as well as conventional anti-leukemic drugs. For all these reasons, VR-ALL may help to gain more insights into the role of Notch signaling in B-ALL. PMID:29719609

  15. Notch3 marks clonogenic mammary luminal progenitor cells in vivo.

    PubMed

    Lafkas, Daniel; Rodilla, Veronica; Huyghe, Mathilde; Mourao, Larissa; Kiaris, Hippokratis; Fre, Silvia

    2013-10-14

    The identity of mammary stem and progenitor cells remains poorly understood, mainly as a result of the lack of robust markers. The Notch signaling pathway has been implicated in mammary gland development as well as in tumorigenesis in this tissue. Elevated expression of the Notch3 receptor has been correlated to the highly aggressive "triple negative" human breast cancer. However, the specific cells expressing this Notch paralogue in the mammary gland remain unknown. Using a conditionally inducible Notch3-CreERT2(SAT) transgenic mouse, we genetically marked Notch3-expressing cells throughout mammary gland development and followed their lineage in vivo. We demonstrate that Notch3 is expressed in a highly clonogenic and transiently quiescent luminal progenitor population that gives rise to a ductal lineage. These cells are capable of surviving multiple successive pregnancies, suggesting a capacity to self-renew. Our results also uncover a role for the Notch3 receptor in restricting the proliferation and consequent clonal expansion of these cells.

  16. Notch3 marks clonogenic mammary luminal progenitor cells in vivo

    PubMed Central

    Lafkas, Daniel; Rodilla, Veronica; Huyghe, Mathilde; Mourao, Larissa; Kiaris, Hippokratis

    2013-01-01

    The identity of mammary stem and progenitor cells remains poorly understood, mainly as a result of the lack of robust markers. The Notch signaling pathway has been implicated in mammary gland development as well as in tumorigenesis in this tissue. Elevated expression of the Notch3 receptor has been correlated to the highly aggressive “triple negative” human breast cancer. However, the specific cells expressing this Notch paralogue in the mammary gland remain unknown. Using a conditionally inducible Notch3-CreERT2SAT transgenic mouse, we genetically marked Notch3-expressing cells throughout mammary gland development and followed their lineage in vivo. We demonstrate that Notch3 is expressed in a highly clonogenic and transiently quiescent luminal progenitor population that gives rise to a ductal lineage. These cells are capable of surviving multiple successive pregnancies, suggesting a capacity to self-renew. Our results also uncover a role for the Notch3 receptor in restricting the proliferation and consequent clonal expansion of these cells. PMID:24100291

  17. N-acetylcysteine negatively regulates Notch3 and its malignant signaling

    PubMed Central

    Zhu, Juan-Juan; Liu, Xue-Xia; You, Hui; Gong, Mei-Ying; Zou, Ming; Cheng, Wen-Hsing; Zhu, Jian-Hong

    2016-01-01

    Notch3 receptor is expressed in a variety of cancers and the excised active intracellular domain (N3ICD) initiates its signaling cascade. N-acetylcysteine (NAC) as an antioxidant has been implicated in cancer prevention and therapy. In this study, we demonstrated a negative regulation of Notch3 by NAC in cancer cells. HeLa cells treated with NAC exhibited a time- and concentration-dependent decrease in Notch3 levels and its downstream effectors Hes1 and HRT1 in a manner independent of f-secretase or glutathione. In contrast, NAC did not affect protein levels of Notch1, the full length Notch3 precursor, or ectopically expressed N3ICD. Although SOD, catalase and NAC suppressed reactive oxygen species in HeLa cells, the first two antioxidants did not impact on Notch3 levels. While the mRNA expression of Notch3 was not altered by NAC, functional inhibition of lysosome, but not proteasome, blocked the NAC-dependent reduction of Notch3 levels. Furthermore, results from Notch3 silencing and N3ICD overexpression demonstrated that NAC prevented malignant phenotypes through down-regulation of Notch3 protein in multiple cancer cells. In summary, NAC reduces Notch3 levels through lysosome-dependent protein degradation, thereby negatively regulates Notch3 malignant signaling in cancer cells. These results implicate a novel NAC treatment in sensitizing Notch3-expressing tumors. PMID:27102435

  18. N-acetylcysteine negatively regulates Notch3 and its malignant signaling.

    PubMed

    Zhang, Xiong; Wang, Ya-Nan; Zhu, Juan-Juan; Liu, Xue-Xia; You, Hui; Gong, Mei-Ying; Zou, Ming; Cheng, Wen-Hsing; Zhu, Jian-Hong

    2016-05-24

    Notch3 receptor is expressed in a variety of cancers and the excised active intracellular domain (N3ICD) initiates its signaling cascade. N-acetylcysteine (NAC) as an antioxidant has been implicated in cancer prevention and therapy. In this study, we demonstrated a negative regulation of Notch3 by NAC in cancer cells. HeLa cells treated with NAC exhibited a time- and concentration-dependent decrease in Notch3 levels and its downstream effectors Hes1 and HRT1 in a manner independent of f-secretase or glutathione. In contrast, NAC did not affect protein levels of Notch1, the full length Notch3 precursor, or ectopically expressed N3ICD. Although SOD, catalase and NAC suppressed reactive oxygen species in HeLa cells, the first two antioxidants did not impact on Notch3 levels. While the mRNA expression of Notch3 was not altered by NAC, functional inhibition of lysosome, but not proteasome, blocked the NAC-dependent reduction of Notch3 levels. Furthermore, results from Notch3 silencing and N3ICD overexpression demonstrated that NAC prevented malignant phenotypes through down-regulation of Notch3 protein in multiple cancer cells. In summary, NAC reduces Notch3 levels through lysosome-dependent protein degradation, thereby negatively regulates Notch3 malignant signaling in cancer cells. These results implicate a novel NAC treatment in sensitizing Notch3-expressing tumors.

  19. Gene expression profiling of the Notch-AhR-IL22 axis at homeostasis and in response to tissue injury.

    PubMed

    Weidenbusch, Marc; Rodler, Severin; Song, Shangqing; Romoli, Simone; Marschner, Julian A; Kraft, Franziska; Holderied, Alexander; Kumar, Santosh; Mulay, Shrikant R; Honarpisheh, Mohsen; Kumar Devarapu, Satish; Lech, Maciej; Anders, Hans-Joachim

    2017-12-22

    Notch and interleukin-22 (IL-22) signaling are known to regulate tissue homeostasis and respond to injury in humans and mice, and the induction of endogenous aryl hydrocarbon receptor (Ahr) ligands through Notch links the two pathways in a hierarchical fashion. However in adults, the species-, organ- and injury-specific gene expression of the Notch-AhR-IL22 axis components is unknown. We therefore performed gene expression profiling of DLL1, DLL3, DLL4, DLK1, DLK2, JAG1, JAG2, Notch1, Notch2, Notch3, Notch4, ADAM17/TNF-α ADAM metalloprotease converting enzyme (TACE), PSEN1, basigin (BSG)/CD147, RBP-J, HES1, HES5, HEY1, HEYL, AHR, ARNT, ARNT2, CYP1A1, CYP24A1, IL-22, IL22RA1, IL22RA2, IL10RB, and STAT3 under homeostatic conditions in ten mature murine and human organs. Additionally, the expression of these genes was assessed in murine models of acute sterile inflammation and progressive fibrosis. We show that there are organ-specific gene expression profiles of the Notch-AhR-IL22 axis in humans and mice. Although there is an overall interspecies congruency, specific differences between human and murine expression signatures do exist. In murine tissues with AHR/ARNT expression CYP1A1 and IL-22 were correlated with HES5 and HEYL expression, while in human tissues no such correlation was found. Notch and AhR signaling are involved in renal inflammation and fibrosis with specific gene expression changes in each model. Despite the presence of all Notch pathway molecules in the kidney and a model-specific induction of Notch ligands, IL-22 was only up-regulated in acute inflammation, but rapidly down-regulated during regeneration. This implies that for targeting injury responses, e.g. via IL-22, species-specific differences, injury type and time points have to be considered. © 2017 The Author(s).

  20. Characterization of activating mutations of NOTCH3 in T-cell acute lymphoblastic leukemia and anti-leukemic activity of NOTCH3 inhibitory antibodies.

    PubMed

    Bernasconi-Elias, P; Hu, T; Jenkins, D; Firestone, B; Gans, S; Kurth, E; Capodieci, P; Deplazes-Lauber, J; Petropoulos, K; Thiel, P; Ponsel, D; Hee Choi, S; LeMotte, P; London, A; Goetcshkes, M; Nolin, E; Jones, M D; Slocum, K; Kluk, M J; Weinstock, D M; Christodoulou, A; Weinberg, O; Jaehrling, J; Ettenberg, S A; Buckler, A; Blacklow, S C; Aster, J C; Fryer, C J

    2016-11-24

    Notch receptors have been implicated as oncogenic drivers in several cancers, the most notable example being NOTCH1 in T-cell acute lymphoblastic leukemia (T-ALL). To characterize the role of activated NOTCH3 in cancer, we generated an antibody that detects the neo-epitope created upon gamma-secretase cleavage of NOTCH3 to release its intracellular domain (ICD3), and sequenced the negative regulatory region (NRR) and PEST (proline, glutamate, serine, threonine) domain coding regions of NOTCH3 in a panel of cell lines. We also characterize NOTCH3 tumor-associated mutations that result in activation of signaling and report new inhibitory antibodies. We determined the structural basis for receptor inhibition by obtaining the first co-crystal structure of a NOTCH3 antibody with the NRR protein and defined two distinct epitopes for NRR antibodies. The antibodies exhibit potent anti-leukemic activity in cell lines and tumor xenografts harboring NOTCH3 activating mutations. Screening of primary T-ALL samples reveals that 2 of 40 tumors examined show active NOTCH3 signaling. We also identified evidence of NOTCH3 activation in 12 of 24 patient-derived orthotopic xenograft models, 2 of which exhibit activation of NOTCH3 without activation of NOTCH1. Our studies provide additional insights into NOTCH3 activation and offer a path forward for identification of cancers that are likely to respond to therapy with NOTCH3 selective inhibitory antibodies.

  1. Characterization of activating mutations of NOTCH3 in T cell acute lymphoblastic leukemia and anti-leukemic activity of NOTCH3 inhibitory antibodies

    PubMed Central

    Bernasconi-Elias, Paula; Hu, Tiancen; Jenkins, David; Firestone, Brant; Gans, Sara; Kurth, Esther; Capodieci, Paola; Deplazes-Lauber, Joelle; Petropoulos, Konstantin; Thiel, Phillip; Ponsel, Dirk; Choi, Sung Hee; LeMotte, Peter; London, Anne; Goetcshkes, Margaret; Nolin, Erin; Jones, Michael D.; Slocum, Kelly; Kluk, Michael J.; Weinstock, David M.; Christodoulou, Alexandra; Weinberg, Olga; Jaehrling, Jan; Ettenberg, Seth A.; Buckler, Alan; Blacklow, Stephen C.; Aster, Jon C.; Fryer, Christy J.

    2016-01-01

    Notch receptors have been implicated as oncogenic drivers in several cancers, the most notable example being NOTCH1 in T-cell acute lymphoblastic leukemia (T-ALL). To characterize the role of activated NOTCH3 in cancer, we generated an antibody that detects the neo-epitope created upon gamma-secretase cleavage of NOTCH3 to release its intracellular domain (ICD3), and sequenced the negative regulatory region (NRR) and PEST domain coding regions of NOTCH3 in a panel of cell lines. We also characterize NOTCH3 tumor-associated mutations that result in activation of signaling and report new inhibitory antibodies. We determined the structural basis for receptor inhibition by obtaining the first co-crystal structure of a NOTCH3 antibody with the NRR protein and defined two distinct epitopes for NRR antibodies. The antibodies exhibit potent anti-leukemic activity in cell lines and tumor xenografts harboring NOTCH3 activating mutations. Screening of primary T-ALL samples reveals that two of 40 tumors examined show active NOTCH3 signaling. We also identified evidence of NOTCH3 activation in 12 of 24 patient-derived orthotopic xenograft models, two of which exhibit activation of NOTCH3 without activation of NOTCH1. Our studies provide additional insights into NOTCH3 activation and offer a path forward for identification of cancers that are likely to respond to therapy with NOTCH3 selective inhibitory antibodies. PMID:27157619

  2. NOTCH3 regulates stem-to-mural cell differentiation in infantile hemangioma.

    PubMed

    Edwards, Andrew K; Glithero, Kyle; Grzesik, Peter; Kitajewski, Alison A; Munabi, Naikhoba Co; Hardy, Krista; Tan, Qian Kun; Schonning, Michael; Kangsamaksin, Thaned; Kitajewski, Jan K; Shawber, Carrie J; Wu, June K

    2017-11-02

    Infantile hemangioma (IH) is a vascular tumor that begins with rapid vascular proliferation shortly after birth, followed by vascular involution in early childhood. We have found that NOTCH3, a critical regulator of mural cell differentiation and maturation, is expressed in hemangioma stem cells (HemSCs), suggesting that NOTCH3 may function in HemSC-to-mural cell differentiation and pathological vessel stabilization. Here, we demonstrate that NOTCH3 is expressed in NG2+PDGFRβ+ perivascular HemSCs and CD31+GLUT1+ hemangioma endothelial cells (HemECs) in proliferating IHs and becomes mostly restricted to the αSMA+NG2loPDGFRβlo mural cells in involuting IHs. NOTCH3 knockdown in HemSCs inhibited in vitro mural cell differentiation and perturbed αSMA expression. In a mouse model of IH, NOTCH3 knockdown or systemic expression of the NOTCH3 inhibitor, NOTCH3 Decoy, significantly decreased IH blood flow, vessel caliber, and αSMA+ perivascular cell coverage. Thus, NOTCH3 is necessary for HemSC-to-mural cell differentiation, and adequate perivascular cell coverage of IH vessels is required for IH vessel stability.

  3. The homeobox gene mirror links EGF signalling to embryonic dorso-ventral axis formation through notch activation.

    PubMed

    Jordan, K C; Clegg, N J; Blasi, J A; Morimoto, A M; Sen, J; Stein, D; McNeill, H; Deng, W M; Tworoger, M; Ruohola-Baker, H

    2000-04-01

    Recent studies in vertebrates and Drosophila melanogaster have revealed that Fringe-mediated activation of the Notch pathway has a role in patterning cell layers during organogenesis. In these processes, a homeobox-containing transcription factor is responsible for spatially regulating fringe (fng) expression and thus directing activation of the Notch pathway along the fng expression border. Here we show that this may be a general mechanism for patterning epithelial cell layers. At three stages in Drosophila oogenesis, mirror (mirr) and fng have complementary expression patterns in the follicle-cell epithelial layer, and at all three stages loss of mirr enlarges, and ectopic expression of mirr restricts, fng expression, with consequences for follicle-cell patterning. These morphological changes are similar to those caused by Notch mutations. Ectopic expression of mirr in the posterior follicle cells induces a stripe of rhomboid (rho) expression and represses pipe (pip), a gene with a role in the establishment of the dorsal-ventral axis, at a distance. Ectopic Notch activation has a similar long-range effect on pip. Our results suggest that Mirror and Notch induce secretion of diffusible morphogens and we have identified TGF-beta (encoded by dpp) as such a molecule in germarium. We also found that mirr expression in dorsal follicle cells is induced by the EGF-receptor (EGFR) pathway and that mirr then represses pip expression in all but the ventral follicle cells, connecting EGFR activation in the dorsal follicle cells to repression of pip in the dorsal and lateral follicle cells. Our results suggest that the differentiation of ventral follicle cells is not a direct consequence of germline signalling, but depends on long-range signals from dorsal follicle cells, and provide a link between early and late events in Drosophila embryonic dorsal-ventral axis formation.

  4. NOR1 promotes hepatocellular carcinoma cell proliferation and migration through modulating the Notch signaling pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    You, Kun; Sun, Peisheng; Yue, Zhongyi

    Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. Previous studies have reported that the oxidored-nitro domain containing protein 1 (NOR1) is a novel tumor suppressor in several tumors. Recent evidence suggests that NOR1 is strongly expressed in HCC cells. However, its role and mechanism in HCC are unclear. In the current study, Western blot and qPCR detected strong NOR1 mRNA and protein expression in HepG2 and Hep3B cells. After transfection with NOR1 siRNA or pcDNA3.1-myc-his-NOR1, the proliferation and migration of HepG2 and Hep3B cells were analyzed in vitro. HepG2 or Hep3B cells overexpressing NOR1 showed anmore » increased proliferation and migration, whereas siRNA-mediated silencing of NOR1 showed the opposite effect. Furthermore, NOR1 activated the Notch signaling pathway, indicated by increased levels of Notch1, NICD, Hes1, and Hey1 in protein. Importantly, the Notch inhibitor DAPT downregulated Notch activation and further enhanced siNOR1-induced reduction of cell proliferation and migration in HepG2 and Hep3B cells, whereas DAPT reversed the effect of NOR1 overexpression on cell proliferation and migration. In conclusion, these results indicate that NOR1 may be involved in the progression of HCC and thus may be a potential target for the treatment of liver cancer. - Highlights: • NOR1 expression is up-regulated in HCC cells. • NOR1 promotes the proliferation and migration of HCC cells. • NOR1 promotes the progression of HCC cells by activating Notch pathway.« less

  5. Differential regulation of Hes/Hey genes during inner ear development.

    PubMed

    Petrovic, Jelena; Gálvez, Hector; Neves, Joana; Abelló, Gina; Giraldez, Fernando

    2015-07-01

    Notch signaling plays a crucial role during inner ear development and regeneration. Hes/Hey genes encode for bHLH transcription factors identified as Notch targets. We have studied the expression and regulation of Hes/Hey genes during inner ear development in the chicken embryo. Among several Hes/Hey genes examined, only Hey1 and Hes5 map to the sensory regions, although with salient differences. Hey1 expression follows Jag1 expression except at early prosensory stages while Hes5 expression corresponds well to Dl1 expression throughout otic development. Although Hey1 and Hes5 are direct Notch downstream targets, they differ in the level of Notch required for activation. Moreover, they also differ in mRNA stability, showing different temporal decays after Notch blockade. In addition, Bmp, Wnt and Fgf pathways also modify Hey1 and Hes5 expression in the inner ear. Particularly, the Wnt pathway modulates Hey1 and Jag1 expression. Finally, gain of function experiments show that Hey1 and Hes5 cross-regulate each other in a complex manner. Both Hey1 and Hes5 repress Dl1 and Hes5 expression, suggesting that they prevent the transition to differentiation stages, probably by preventing Atoh1 expression. In spite of its association with Jag1, Hey1 does not seem to be instrumental for lateral induction as it does not promote Jag1 expression. We suggest that, besides being both targets of Notch, Hey1 and Hes5 are subject to a rather complex regulation that includes the stability of their transcripts, cross regulation and other signaling pathways. © 2014 Wiley Periodicals, Inc.

  6. Notch1-Dll4 signaling and mechanical force regulate leader cell formation during collective cell migration

    PubMed Central

    Riahi, Reza; Sun, Jian; Wang, Shue; Long, Min; Zhang, Donna D.; Wong, Pak Kin

    2015-01-01

    At the onset of collective cell migration, a subset of cells within an initially homogenous population acquires a distinct “leader” phenotype with characteristic morphology and motility. However, the factors driving leader cell formation as well as the mechanisms regulating leader cell density during the migration process remain to be determined. Here, we use single cell gene expression analysis and computational modeling to show that leader cell identity is dynamically regulated by Dll4 signaling through both Notch1 and cellular stress in a migrating epithelium. Time-lapse microscopy reveals that Dll4 is induced in leader cells after the creation of the cell-free region and leader cells are regulated via Notch1-Dll4 lateral inhibition. Furthermore, mechanical stress inhibits Dll4 expression and leader cell formation in the monolayer. Collectively, our findings suggest that a reduction of mechanical force near the boundary promotes Notch1-Dll4 signaling to dynamically regulate the density of leader cells during collective cell migration. PMID:25766473

  7. Associations between polymorphisms in the NICD domain of bovine NOTCH1 gene and growth traits in Chinese Qinchuan cattle.

    PubMed

    Liu, Mei; Zhang, Chenge; Lai, Xinsheng; Xue, Jing; Lan, Xianyong; Lei, Chuzhao; Jia, Yutang; Chen, Hong

    2017-05-01

    NOTCH1 is one of the four mammalian Notch receptors, which is involved in the Notch signaling pathway. Specifically, NOTCH1 promotes the proliferation of myogenic precursor cells, and the NICD domain of NOTCH1 can impair regeneration of skeletal muscles. However, similar research on the bovine NOTCH1 gene is lacking. In this study, we detected the polymorphisms of the bovine NOTCH1 gene in a total of 448 individuals from Chinese Qinchuan cattle with DNA pooling, forced PCR-RFLP, and DNA sequencing methods. Five novel SNPs were identified within the NICD domain, and eight haplotypes comprising combinations of these five SNPs were studied as well. The association analysis of SNPs' effects with growth traits revealed that g.A48250G was significantly associated with body height, body weight, and height at hip cross, and that g.A49239C only showed significant associations with body height. This suggests that the NOTCH1 gene is a strong candidate gene that could be utilized as a promising marker in beef cattle breeding programs.

  8. Deletion of Notch1 converts pro-T cells to dendritic cells and promotes thymic B cells by cell-extrinsic and cell-intrinsic mechanisms.

    PubMed

    Feyerabend, Thorsten B; Terszowski, Grzegorz; Tietz, Annette; Blum, Carmen; Luche, Hervé; Gossler, Achim; Gale, Nicholas W; Radtke, Freddy; Fehling, Hans Jörg; Rodewald, Hans-Reimer

    2009-01-16

    Notch1 signaling is required for T cell development and has been implicated in fate decisions in the thymus. We showed that Notch1 deletion in progenitor T cells (pro-T cells) revealed their latent developmental potential toward becoming conventional and plasmacytoid dendritic cells. In addition, Notch1 deletion in pro-T cells resulted in large numbers of thymic B cells, previously explained by T-to-B cell fate conversion. Single-cell genotyping showed, however, that the majority of these thymic B cells arose from Notch1-sufficient cells by a cell-extrinsic pathway. Fate switching nevertheless exists for a subset of thymic B cells originating from Notch1-deleted pro-T cells. Chimeric mice lacking the Notch ligand delta-like 4 (Dll4) in thymus epithelium revealed an essential role for Dll4 in T cell development. Thus, Notch1-Dll4 signaling fortifies T cell commitment by suppressing non-T cell lineage potential in pro-T cells, and normal Notch1-driven T cell development repels excessive B cells in the thymus.

  9. Conserved genetic pathways controlling the development of the diffuse endocrine system in vertebrates and Drosophila.

    PubMed

    Hartenstein, Volker; Takashima, Shigeo; Adams, Katrina L

    2010-05-01

    The midgut epithelium is formed by absorptive enterocytes, secretory cells and endocrine cells. Each of these lineages is derived from the pluripotent progenitors that constitute the embryonic endoderm; the mature midgut retains pools of self-renewing stem cells that continue to produce all lineages. Recent findings in vertebrates and Drosophila shed light on the genetic mechanism that specifies the fate of the different lineages. A pivotal role is played by the Notch signaling pathway that, in a manner that appears to be very similar to the way in which Notch signaling selects neural progenitors within the neurectoderm, distinguishes the fate of secretory/endocrine cells and enterocytes. Proneural genes encoding bHLH transcription factors are expressed and required in prospective endocrine cells; activation of the Notch pathways restricts the number of these cells and promotes enterocyte development. In this review we compare the development of the intestinal endocrine cells in vertebrates and insects and summarize recent findings dealing with genetic pathways controlling this cell type. Copyright 2009. Published by Elsevier Inc.

  10. Investigational Notch and Hedgehog Inhibitors – Therapies for Cardiovascular disease

    PubMed Central

    Redmond, EM; Guha, S; Walls, D; Cahill, PA

    2011-01-01

    Importance to the field During the past decade a variety of Notch and Hedgehog pathway inhibitors have been developed for the treatment of several cancers. An emerging paradigm suggests that these same gene regulatory networks are often recapitulated in the context of cardiovascular disease and may now offer an attractive target for therapeutic intervention. Areas Covered This article briefly reviews the profile of Notch and Hedgehog inhibitors that have reached the pre-clinic and clinic for cancer treatment and discusses the clinical issues surrounding targeted use of these inhibitors in the treatment of vascular disorders. Expert Opinion Pre-clinical and clinical data using pan-Notch inhibitors (γ-secretase inhibitors) and selective antibodies to preferentially target notch receptors and ligands has proven successful but concerns remain over normal organ homeostasis and significant pathology in multiple organs. In contrast, the Hedgehog based drug pipeline is rich with more than a dozen Smoothened (SMO) inhibitors at various stages of development. Overall, refined strategies will be necessary to harness these pathways safely as a powerful tool to disrupt angiogenesis and vascular proliferative phenomena without causing prohibitive side effects already seen with cancer models and patients. PMID:22007748

  11. CONNECTIVE TISSUE GROWTH FACTOR IS A TARGET OF NOTCH SIGNALING IN CELLS OF THE OSTEOBLASTIC LINEAGE

    PubMed Central

    Canalis, Ernesto; Zanotti, Stefano; Smerdel-Ramoya, Anna

    2014-01-01

    Connective tissue growth factor (Ctgf) or CCN2 is a protein synthesized by osteoblasts necessary for skeletal homeostasis, although its overexpression inhibits osteogenic signals and bone formation. Ctgf is induced by bone morphogenetic proteins, transforming growth factor β and Wnt; and in the present studies, we explored whether Notch regulated Ctgf expression in osteoblasts. We employed RosaNotch mice, where the Notch intracellular domain (NICD) is expressed following the excision of a STOP cassette, placed between the Rosa26 promoter and NICD. Notch was activated by transduction of adenoviral vectors expressing Cre recombinase (Ad-CMV-Cre). Notch induced Ctgf mRNA levels in a time dependent manner and increased Ctgf heterogeneous nuclear RNA. Notch also destabilized Ctgf mRNA shortening its half-life from 13 h to 3 h. The effect of Notch on Ctgf expression was lost following Rbpjκ downregulation, demonstrating that it was mediated by Notch canonical signaling. However, downregulation of the classic Notch target genes Hes1, Hey1 and Hey2 did not modify the effect of Notch on Ctgf expression. Wild type osteoblasts exposed to immobilized Delta-like 1 displayed enhanced Notch signaling and increased Ctgf expression. In addition to the effects of Notch in vitro, Notch induced Ctgf in vivo, and calvariae and femurs from RosaNotch mice mated with transgenics expressing the Cre recombinase in cells of the osteoblastic lineage exhibited increased expression of Ctgf. In conclusion, Ctgf is a target of Notch canonical signaling in osteoblasts, and may act in concert with Notch to regulate skeletal homeostasis. PMID:24792956

  12. Antiangiogenic and tumour inhibitory effects of downregulating tumour endothelial FABP4

    PubMed Central

    Harjes, U; Bridges, E; Gharpure, K M; Roxanis, I; Sheldon, H; Miranda, F; Mangala, L S; Pradeep, S; Lopez-Berestein, G; Ahmed, A; Fielding, B; Sood, A K; Harris, A L

    2017-01-01

    Fatty acid binding protein 4 (FABP4) is a fatty acid chaperone, which is induced during adipocyte differentiation. Previously we have shown that FABP4 in endothelial cells is induced by the NOTCH1 signalling pathway, the latter of which is involved in mechanisms of resistance to antiangiogenic tumour therapy. Here, we investigated the role of FABP4 in endothelial fatty acid metabolism and tumour angiogenesis. We analysed the effect of transient FABP4 knockdown in human umbilical vein endothelial cells on fatty acid metabolism, viability and angiogenesis. Through therapeutic delivery of siRNA targeting mouse FABP4, we investigated the effect of endothelial FABP4 knockdown on tumour growth and blood vessel formation. In vitro, siRNA-mediated FABP4 knockdown in endothelial cells led to a marked increase of endothelial fatty acid oxidation, an increase of reactive oxygen species and decreased angiogenesis. In vivo, we found that increased NOTCH1 signalling in tumour xenografts led to increased expression of endothelial FABP4 that decreased when NOTCH1 and VEGFA inhibitors were used in combination. Angiogenesis, growth and metastasis in ovarian tumour xenografts were markedly inhibited by therapeutic siRNA delivery targeting mouse endothelial FABP4. Therapeutic targeting of endothelial FABP4 by siRNA in vivo has antiangiogenic and antitumour effects with minimal toxicity and should be investigated further. PMID:27568980

  13. Antiangiogenic and tumour inhibitory effects of downregulating tumour endothelial FABP4.

    PubMed

    Harjes, U; Bridges, E; Gharpure, K M; Roxanis, I; Sheldon, H; Miranda, F; Mangala, L S; Pradeep, S; Lopez-Berestein, G; Ahmed, A; Fielding, B; Sood, A K; Harris, A L

    2017-02-16

    Fatty acid binding protein 4 (FABP4) is a fatty acid chaperone, which is induced during adipocyte differentiation. Previously we have shown that FABP4 in endothelial cells is induced by the NOTCH1 signalling pathway, the latter of which is involved in mechanisms of resistance to antiangiogenic tumour therapy. Here, we investigated the role of FABP4 in endothelial fatty acid metabolism and tumour angiogenesis. We analysed the effect of transient FABP4 knockdown in human umbilical vein endothelial cells on fatty acid metabolism, viability and angiogenesis. Through therapeutic delivery of siRNA targeting mouse FABP4, we investigated the effect of endothelial FABP4 knockdown on tumour growth and blood vessel formation. In vitro, siRNA-mediated FABP4 knockdown in endothelial cells led to a marked increase of endothelial fatty acid oxidation, an increase of reactive oxygen species and decreased angiogenesis. In vivo, we found that increased NOTCH1 signalling in tumour xenografts led to increased expression of endothelial FABP4 that decreased when NOTCH1 and VEGFA inhibitors were used in combination. Angiogenesis, growth and metastasis in ovarian tumour xenografts were markedly inhibited by therapeutic siRNA delivery targeting mouse endothelial FABP4. Therapeutic targeting of endothelial FABP4 by siRNA in vivo has antiangiogenic and antitumour effects with minimal toxicity and should be investigated further.

  14. Disruption of zebrafish cyclin G-associated kinase (GAK) function impairs the expression of Notch-dependent genes during neurogenesis and causes defects in neuronal development

    PubMed Central

    2010-01-01

    Background The J-domain-containing protein auxilin, a critical regulator in clathrin-mediated transport, has been implicated in Drosophila Notch signaling. To ask if this role of auxilin is conserved and whether auxilin has additional roles in development, we have investigated the functions of auxilin orthologs in zebrafish. Results Like mammals, zebrafish has two distinct auxilin-like molecules, auxilin and cyclin G-associated kinase (GAK), differing in their domain structures and expression patterns. Both zebrafish auxilin and GAK can functionally substitute for the Drosophila auxilin, suggesting that they have overlapping molecular functions. Still, they are not completely redundant, as morpholino-mediated knockdown of the ubiquitously expressed GAK alone can increase the specification of neuronal cells, a known Notch-dependent process, and decrease the expression of Her4, a Notch target gene. Furthermore, inhibition of GAK function caused an elevated level of apoptosis in neural tissues, resulting in severe degeneration of neural structures. Conclusion In support of the notion that endocytosis plays important roles in Notch signaling, inhibition of zebrafish GAK function affects embryonic neuronal cell specification and Her4 expression. In addition, our analysis suggests that zebrafish GAK has at least two functions during the development of neural tissues: an early Notch-dependent role in neuronal patterning and a late role in maintaining the survival of neural cells. PMID:20082716

  15. AKAP200 promotes Notch stability by protecting it from Cbl/lysosome-mediated degradation in Drosophila melanogaster.

    PubMed

    Bala Tannan, Neeta; Collu, Giovanna; Humphries, Ashley C; Serysheva, Ekatherina; Weber, Ursula; Mlodzik, Marek

    2018-01-01

    AKAP200 is a Drosophila melanogaster member of the "A Kinase Associated Protein" family of scaffolding proteins, known for their role in the spatial and temporal regulation of Protein Kinase A (PKA) in multiple signaling contexts. Here, we demonstrate an unexpected function of AKAP200 in promoting Notch protein stability. In Drosophila, AKAP200 loss-of-function (LOF) mutants show phenotypes that resemble Notch LOF defects, including eye patterning and sensory organ specification defects. Through genetic interactions, we demonstrate that AKAP200 interacts positively with Notch in both the eye and the thorax. We further show that AKAP200 is part of a physical complex with Notch. Biochemical studies reveal that AKAP200 stabilizes endogenous Notch protein, and that it limits ubiquitination of Notch. Specifically, our genetic and biochemical evidence indicates that AKAP200 protects Notch from the E3-ubiquitin ligase Cbl, which targets Notch to the lysosomal pathway. Indeed, we demonstrate that the effect of AKAP200 on Notch levels depends on the lysosome. Interestingly, this function of AKAP200 is fully independent of its role in PKA signaling and independent of its ability to bind PKA. Taken together, our data indicate that AKAP200 is a novel tissue specific posttranslational regulator of Notch, maintaining high Notch protein levels and thus promoting Notch signaling.

  16. The significance of PTEN and AKT aberrations in pediatric T-cell acute lymphoblastic leukemia

    PubMed Central

    Zuurbier, Linda; Petricoin, Emanuel F.; Vuerhard, Maartje J.; Calvert, Valerie; Kooi, Clarissa; Buijs-Gladdines, Jessica G.C.A.M.; Smits, Willem K.; Sonneveld, Edwin; Veerman, Anjo J.P.; Kamps, Willem A.; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2012-01-01

    Background PI3K/AKT pathway mutations are found in T-cell acute lymphoblastic leukemia, but their overall impact and associations with other genetic aberrations is unknown. PTEN mutations have been proposed as secondary mutations that follow NOTCH1-activating mutations and cause cellular resistance to γ-secretase inhibitors. Design and Methods The impact of PTEN, PI3K and AKT aberrations was studied in a genetically well-characterized pediatric T-cell leukemia patient cohort (n=146) treated on DCOG or COALL protocols. Results PTEN and AKT E17K aberrations were detected in 13% and 2% of patients, respectively. Defective PTEN-splicing was identified in incidental cases. Patients without PTEN protein but lacking exon-, splice-, promoter mutations or promoter hypermethylation were present. PTEN/AKT mutations were especially abundant in TAL- or LMO-rearranged leukemia but nearly absent in TLX3-rearranged patients (P=0.03), the opposite to that observed for NOTCH1-activating mutations. Most PTEN/AKT mutant patients either lacked NOTCH1-activating mutations (P=0.006) or had weak NOTCH1-activating mutations (P=0.011), and consequently expressed low intracellular NOTCH1, cMYC and MUSASHI levels. T-cell leukemia patients without PTEN/AKT and NOTCH1-activating mutations fared well, with a cumulative incidence of relapse of only 8% versus 35% for PTEN/AKT and/or NOTCH1-activated patients (P=0.005). Conclusions PI3K/AKT pathway aberrations are present in 18% of pediatric T-cell acute lymphoblastic leukemia patients. Absence of strong NOTCH1-activating mutations in these cases may explain cellular insensitivity to γ-secretase inhibitors. PMID:22491738

  17. Protein Tyrosine Phosphatase PRL2 Mediates Notch and Kit Signals in Early T Cell Progenitors.

    PubMed

    Kobayashi, Michihiro; Nabinger, Sarah C; Bai, Yunpeng; Yoshimoto, Momoko; Gao, Rui; Chen, Sisi; Yao, Chonghua; Dong, Yuanshu; Zhang, Lujuan; Rodriguez, Sonia; Yashiro-Ohtani, Yumi; Pear, Warren S; Carlesso, Nadia; Yoder, Mervin C; Kapur, Reuben; Kaplan, Mark H; Daniel Lacorazza, Hugo; Zhang, Zhong-Yin; Liu, Yan

    2017-04-01

    The molecular pathways regulating lymphoid priming, fate, and development of multipotent bone marrow hematopoietic stem and progenitor cells (HSPCs) that continuously feed thymic progenitors remain largely unknown. While Notch signal is indispensable for T cell specification and differentiation, the downstream effectors are not well understood. PRL2, a protein tyrosine phosphatase that regulates hematopoietic stem cell proliferation and self-renewal, is highly expressed in murine thymocyte progenitors. Here we demonstrate that protein tyrosine phosphatase PRL2 and receptor tyrosine kinase c-Kit are critical downstream targets and effectors of the canonical Notch/RBPJ pathway in early T cell progenitors. While PRL2 deficiency resulted in moderate defects of thymopoiesis in the steady state, de novo generation of T cells from Prl2 null hematopoietic stem cells was significantly reduced following transplantation. Prl2 null HSPCs also showed impaired T cell differentiation in vitro. We found that Notch/RBPJ signaling upregulated PRL2 as well as c-Kit expression in T cell progenitors. Further, PRL2 sustains Notch-mediated c-Kit expression and enhances stem cell factor/c-Kit signaling in T cell progenitors, promoting effective DN1-DN2 transition. Thus, we have identified a critical role for PRL2 phosphatase in mediating Notch and c-Kit signals in early T cell progenitors. Stem Cells 2017;35:1053-1064. © 2016 AlphaMed Press.

  18. Characterization of Aes nuclear foci in colorectal cancer cells

    PubMed Central

    Itatani, Yoshiro; Sonoshita, Masahiro; Kakizaki, Fumihiko; Okawa, Katsuya; Stifani, Stefano; Itoh, Hideaki; Sakai, Yoshiharu; Taketo, M. Mark

    2016-01-01

    Amino-terminal enhancer of split (Aes) is a member of Groucho/Transducin-like enhancer (TLE) family. Aes is a recently found metastasis suppressor of colorectal cancer (CRC) that inhibits Notch signalling, and forms nuclear foci together with TLE1. Although some Notch-associated proteins are known to form subnuclear bodies, little is known regarding the dynamics or functions of these structures. Here, we show that Aes nuclear foci in CRC observed under an electron microscope are in a rather amorphous structure, lacking surrounding membrane. Investigation of their behaviour during the cell cycle by time-lapse cinematography showed that Aes nuclear foci dissolve during mitosis and reassemble after completion of cytokinesis. We have also found that heat shock cognate 70 (HSC70) is an essential component of Aes foci. Pharmacological inhibition of the HSC70 ATPase activity with VER155008 reduces Aes focus formation. These results provide insight into the understanding of Aes-mediated inhibition of Notch signalling. PMID:26229111

  19. DEAE-Dextran coated paclitaxel nanoparticles act as multifunctional nano system for intranuclear delivery to triple negative breast cancer through VEGF and NOTCH1 inhibition.

    PubMed

    Bakrania, Anita K; Variya, Bhavesh C; Rathod, Lalaji V; Patel, Snehal S

    2018-01-01

    Triple negative breast cancer revolution has identified a plethora of therapeutic targets making it apparent that a single target for its treatment could be rare hence creating an urge to develop robust technologies for combination drug therapy. Paclitaxel, hailed as the most significant advancement in chemotherapy faces several underpinnings due to its low solubility and permeability. Advancing research has demonstrated the role of interferons in cancer. DEAE-Dextran, an emerging molecule with evidence of interferon induction was utilized in the present study to develop a nanoformulation in conjugation with paclitaxel to target multiple therapeutic pathways, with diminution of paclitaxel adverse effects and develop a specific targeted nano system. Evidently, it was demonstrated that DEAE-Dextran coated nanoformulation portrays significant synergistic cytotoxicity in the various cell lines. Moreover, overcoming the activation of ROS by paclitaxel, the combination drug therapy more effectively inhibited ROS through β-interferon induction. The nanoformulation was further conjugated to FITC for internalization studies which subsequently indicated maximum cellular uptake at 60min post treatment demonstrated by green fluorescence from FITC lighting up the nuclear membrane. Precisely, the mechanistic approach of nuclear-targeted nanoformulation was evaluated by in vivo xenograft studies which showed a synergistic release of β-interferon at the target organ. Moreover, the combination nanoformulation inculcated multiple mechanistic approaches through VEGF and NOTCH1 inhibition along with dual β and γ-interferon overexpression. Overall, the combination therapy may be a promising multifunctional nanomaterial for intranuclear drug delivery in TNBC. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Area-Specific Regulation of Quiescent Neural Stem Cells by Notch3 in the Adult Mouse Subependymal Zone.

    PubMed

    Kawai, Hiroki; Kawaguchi, Daichi; Kuebrich, Benjamin D; Kitamoto, Takeo; Yamaguchi, Masahiro; Gotoh, Yukiko; Furutachi, Shohei

    2017-12-06

    In the adult mammalian brain, neural stem cells (NSCs) generate new neurons throughout the mammal's lifetime. The balance between quiescence and active cell division among NSCs is crucial in producing appropriate numbers of neurons while maintaining the stem cell pool for a long period. The Notch signaling pathway plays a central role in both maintaining quiescent NSCs (qNSCs) and promoting cell division of active NSCs (aNSCs), although no one knows how this pathway regulates these apparently opposite functions. Notch1 has been shown to promote proliferation of aNSCs without affecting qNSCs in the adult mouse subependymal zone (SEZ). In this study, we found that Notch3 is expressed to a higher extent in qNSCs than in aNSCs while Notch1 is preferentially expressed in aNSCs and transit-amplifying progenitors in the adult mouse SEZ. Furthermore, Notch3 is selectively expressed in the lateral and ventral walls of the SEZ. Knockdown of Notch3 in the lateral wall of the adult SEZ increased the division of NSCs. Moreover, deletion of the Notch3 gene resulted in significant reduction of qNSCs specifically in the lateral and ventral walls, compared with the medial and dorsal walls, of the lateral ventricles. Notch3 deletion also reduced the number of qNSCs activated after antimitotic cytosine β-D-arabinofuranoside (Ara-C) treatment. Importantly, Notch3 deletion preferentially reduced specific subtypes of newborn neurons in the olfactory bulb derived from the lateral walls of the SEZ. These results indicate that Notch isoforms differentially control the quiescent and proliferative steps of adult SEZ NSCs in a domain-specific manner. SIGNIFICANCE STATEMENT In the adult mammalian brain, the subependymal zone (SEZ) of the lateral ventricles is the largest neurogenic niche, where neural stem cells (NSCs) generate neurons. In this study, we found that Notch3 plays an important role in the maintenance of quiescent NSCs (qNSCs), while Notch1 has been reported to act as a regulator of actively cycling NSCs. Furthermore, we found that Notch3 is specifically expressed in qNSCs located in the lateral and ventral walls of the lateral ventricles and regulates neuronal production of NSCs in a region-specific manner. Our results indicate that Notch3, by maintaining the quiescence of a subpopulation of NSCs, confers a region-specific heterogeneity among NSCs in the adult SEZ. Copyright © 2017 the authors 0270-6474/17/3711867-14$15.00/0.

  1. Notch-Induced Expression of FZD7 Requires Noncanonical NOTCH3 Signaling in Human Breast Epithelial Cells.

    PubMed

    Bhat, Vasudeva; Sun, Yu Jia; Weger, Steve; Raouf, Afshin

    2016-04-01

    The evolutionarily conserved Notch and Wnt signaling pathways have demonstrated roles in normal mammary gland development and in breast carcinogenesis. We previously reported that in human mammary gland, signaling through NOTCH3 alone regulates the commitment of the undifferentiated bipotential progenitors to the luminal cell fate, indicating that NOTCH3 may regulate the expression of unique genes apart from the other Notch receptors. In this study, we used gain of function and loss of function experiments and found that a Wnt signaling receptor, Frizzled7 (FZD7), is a unique and nonredundant target of NOTCH3 in human breast epithelial cells. Interestingly, neither the constitutively active forms of NOTCH1-2, 4 nor loss of expression of these receptors were able to alter expression of FZD7 in human breast epithelial cells. We further show that FZD7-expressing cells are found more frequently in the luminal progenitor-enriched subpopulation of cells obtained from breast reduction samples compared with the undifferentiated bipotent progenitors. Also, we show that NOTCH3-induced expression of FZD7 occurs in the absence of CSL (CBF1-Suppressor of Hairless-Lag-1). Our data suggest that noncanonical Notch signaling through NOTCH3 could modulate Wnt signaling via FZD7 and in this way, might be involved in luminal cell differentiation.

  2. SCL, LMO1 and Notch1 Reprogram Thymocytes into Self-Renewing Cells

    PubMed Central

    Rojas-Sutterlin, Shanti; Herblot, Sabine; Hébert, Josée; Sauvageau, Guy; Lemieux, Sébastien; Lécuyer, Eric; Veiga, Diogo F. T.; Hoang, Trang

    2014-01-01

    The molecular determinants that render specific populations of normal cells susceptible to oncogenic reprogramming into self-renewing cancer stem cells are poorly understood. Here, we exploit T-cell acute lymphoblastic leukemia (T-ALL) as a model to define the critical initiating events in this disease. First, thymocytes that are reprogrammed by the SCL and LMO1 oncogenic transcription factors into self-renewing pre-leukemic stem cells (pre-LSCs) remain non-malignant, as evidenced by their capacities to generate functional T cells. Second, we provide strong genetic evidence that SCL directly interacts with LMO1 to activate the transcription of a self-renewal program coordinated by LYL1. Moreover, LYL1 can substitute for SCL to reprogram thymocytes in concert with LMO1. In contrast, inhibition of E2A was not sufficient to substitute for SCL, indicating that thymocyte reprogramming requires transcription activation by SCL-LMO1. Third, only a specific subset of normal thymic cells, known as DN3 thymocytes, is susceptible to reprogramming. This is because physiological NOTCH1 signals are highest in DN3 cells compared to other thymocyte subsets. Consistent with this, overexpression of a ligand-independent hyperactive NOTCH1 allele in all immature thymocytes is sufficient to sensitize them to SCL-LMO1, thereby increasing the pool of self-renewing cells. Surprisingly, hyperactive NOTCH1 cannot reprogram thymocytes on its own, despite the fact that NOTCH1 is activated by gain of function mutations in more than 55% of T-ALL cases. Rather, elevating NOTCH1 triggers a parallel pathway involving Hes1 and Myc that dramatically enhances the activity of SCL-LMO1 We conclude that the acquisition of self-renewal and the genesis of pre-LSCs from thymocytes with a finite lifespan represent a critical first event in T-ALL. Finally, LYL1 and LMO1 or LMO2 are co-expressed in most human T-ALL samples, except the cortical T subtype. We therefore anticipate that the self-renewal network described here may be relevant to a majority of human T-ALL. PMID:25522233

  3. NOTCH1 and FBXW7 mutations have a favorable impact on early response to treatment, but not on outcome, in children with T-cell acute lymphoblastic leukemia (T-ALL) treated on EORTC trials 58881 and 58951.

    PubMed

    Clappier, E; Collette, S; Grardel, N; Girard, S; Suarez, L; Brunie, G; Kaltenbach, S; Yakouben, K; Mazingue, F; Robert, A; Boutard, P; Plantaz, D; Rohrlich, P; van Vlierberghe, P; Preudhomme, C; Otten, J; Speleman, F; Dastugue, N; Suciu, S; Benoit, Y; Bertrand, Y; Cavé, H

    2010-12-01

    Risk-adjusted treatment stratification in T-cell acute lymphoblastic leukemias (T-ALLs) is currently based only on early response to chemotherapy. We investigated the prognostic implication of hyperactivation of NOTCH pathway resulting from mutations of NOTCH1 or FBXW7 in children with T-ALL enrolled in EORTC-CLG trials. Overall, 80 out of 134 (60%) patients were NOTCH+ (NOTCH1 and/or FBXW7 mutated). Although clinical presentations were not significantly associated with NOTCH status, NOTCH+ patients showed a better early response to chemotherapy as compared with NOTCH- patients, according to the rate of poor pre-phase 'responders' (25% versus 44%; P=0.02) and the incidence of high minimal residual disease (MRD) levels (11% (7/62) versus 32% (10/31); P=0.01) at completion of induction. However, the outcome of NOTCH+ patients was similar to that of NOTCH- patients, with a 5-year event-free survival (EFS) of 73% and 70% (P=0.82), and 5-year overall survival of 82% and 79% (P=0.62), respectively. In patients with high MRD levels, the 5-year EFS rate was 0% (NOTCH+) versus 42% (NOTCH-), whereas in those with low MRD levels, the outcome was similar: 76% (NOTCH+) versus 78% (NOTCH-). The incidence of isolated central nervous system (CNS) relapses was relatively high in NOTCH1+ patients (8.3%), which could be related to a higher propensity of NOTCH+ leukemic blasts to target the CNS.

  4. Correlation of ALDH1 and Notch3 Expression: Clinical implication in Ovarian Carcinomas.

    PubMed

    Kim, Mi Joung; Kim, A-Ram; Jeong, Ju-Yeon; Kim, Kwang-Il; Kim, Tae-Heon; Lee, Chan; Chung, Kwanghoe; Ko, Young-Hyeh; An, Hee-Jung

    2017-01-01

    Purpose : ALDH1 is a putative cancer stem cell marker, while the Notch signaling pathway is involved in regulation of cancer stem cell (CSC)s. This study aims to determine the expression of Notch signaling genes in ovarian CSCs, and to assess the clinical impact of expression of ALDH1 and Notch signaling genes in ovarian cancers. Methods : We examined expression of Notch signaling genes in FACS-sorted ALDH1(+) putative ovarian CSCs and expression of ALDH1 and Notch signaling genes in 86 ovarian epithelial tumors and various ovarian cancer cell lines by real-time RT-PCR, including Notch receptors ( Notch1-4 ), Notch ligands ( Jagged1 and Jagged2 ), and the downstream molecule, Hes1 . Furthermore, we correlated their expression with clinicopathological parameters and patient's survival in ovarian serous carcinoma (OSC)s, the most prevalent type of ovarian cancer. Results : The higher expression levels of ALDH1 and Notch related genes, especially Notch3 were associated with CSCs and with chemoresistant OSCs and paclitaxel-resistant SKpac ovarian cancer cells. Among the Notch signaling genes, high Notch3 expression was significantly associated with all the parameters of poor prognosis, i.e., advanced stage, lymph node and distant metastases, and chemoresistance, whereas other genes were less correlated with these parameters. A combined upregulation of ALDH1 and Notch3 was an independent poor prognostic factor in OSCs. Conclusions : ALDH1 correlates with Notch3 expression in ovarian carcinomas. ALDH1 and Notch3 overexpression is an independent poor prognostic indicator for worse patient's survival in this subset of OSCs.

  5. Bergamot natural products eradicate cancer stem cells (CSCs) by targeting mevalonate, Rho-GDI-signalling and mitochondrial metabolism.

    PubMed

    Fiorillo, Marco; Peiris-Pagès, Maria; Sanchez-Alvarez, Rosa; Bartella, Lucia; Di Donna, Leonardo; Dolce, Vincenza; Sindona, Giovanni; Sotgia, Federica; Cappello, Anna Rita; Lisanti, Michael P

    2018-04-04

    Here, we show that a 2:1 mixture of Brutieridin and Melitidin, termed "BMF", has a statin-like properties, which blocks the action of the rate-limiting enzyme for mevalonate biosynthesis, namely HMGR (3-hydroxy-3-methylglutaryl-CoA-reductase). Moreover, our results indicate that BMF functionally inhibits several key characteristics of CSCs. More specifically, BMF effectively i) reduced ALDH activity, ii) blocked mammosphere formation and iii) inhibited the activation of CSC-associated signalling pathways (STAT1/3, Notch and Wnt/beta-catenin) targeting Rho-GDI-signalling. In addition, BMF metabolically inhibited mitochondrial respiration (OXPHOS) and fatty acid oxidation (FAO). Importantly, BMF did not show the same toxic side-effects in normal fibroblasts that were observed with statins. Lastly, we show that high expression of the mRNA species encoding HMGR is associated with poor clinical outcome in breast cancer patients, providing a potential companion diagnostic for BMF-directed personalized therapy. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Muscle contraction is required to maintain the pool of muscle progenitors via YAP and NOTCH during fetal myogenesis.

    PubMed

    Esteves de Lima, Joana; Bonnin, Marie-Ange; Birchmeier, Carmen; Duprez, Delphine

    2016-08-24

    The importance of mechanical activity in the regulation of muscle progenitors during chick development has not been investigated. We show that immobilization decreases NOTCH activity and mimics a NOTCH loss-of-function phenotype, a reduction in the number of muscle progenitors and increased differentiation. Ligand-induced NOTCH activation prevents the reduction of muscle progenitors and the increase of differentiation upon immobilization. Inhibition of NOTCH ligand activity in muscle fibers suffices to reduce the progenitor pool. Furthermore, immobilization reduces the activity of the transcriptional co-activator YAP and the expression of the NOTCH ligand JAG2 in muscle fibers. YAP forced-activity in muscle fibers prevents the decrease of JAG2 expression and the number of PAX7+ cells in immobilization conditions. Our results identify a novel mechanism acting downstream of muscle contraction, where YAP activates JAG2 expression in muscle fibers, which in turn regulates the pool of fetal muscle progenitors via NOTCH in a non-cell-autonomous manner.

  7. Notch3 is necessary for neuronal differentiation and maturation in the adult spinal cord.

    PubMed

    Rusanescu, Gabriel; Mao, Jianren

    2014-10-01

    Notch receptors are key regulators of nervous system development and promoters of neural stem cells renewal and proliferation. Defects in the expression of Notch genes result in severe, often lethal developmental abnormalities. Notch3 is generally thought to have a similar proliferative, anti-differentiation and gliogenic role to Notch1. However, in some cases, Notch3 has an opposite, pro-differentiation effect. Here, we show that Notch3 segregates from Notch1 and is transiently expressed in adult rat and mouse spinal cord neuron precursors and immature neurons. This suggests that during the differentiation of adult neural progenitor cells, Notch signalling may follow a modified version of the classical lateral inhibition model, involving the segregation of individual Notch receptors. Notch3 knockout mice, otherwise neurologically normal, are characterized by a reduced number of mature inhibitory interneurons and an increased number of highly excitable immature neurons in spinal cord laminae I-II. As a result, these mice have permanently lower nociceptive thresholds, similar to chronic pain. These results suggest that defective neuronal differentiation, for example as a result of reduced Notch3 expression or activation, may underlie human cases of intractable chronic pain, such as fibromyalgia and neuropathic pain. © 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  8. Novel anticancer activity of phloroglucinol against breast cancer stem-like cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Rae-Kwon; Uddin, Nizam; Hyun, Jin-Won

    Poor prognosis of breast cancer patients is closely associated with metastasis and relapse. There is substantial evidence supporting that cancer stem-like cells (CSCs) are primarily responsible for relapse in breast cancer after anticancer treatment. However, there is a lack of suitable drugs that target breast cancer stem-like cells (BCSCs). Here, we report that phloroglucinol (PG), a natural phlorotannin component of brown algae, suppresses sphere formation, anchorage-independent colony formation and in vivo tumorigenicity. In line with these observations, treatment with PG also decreased CD44{sup +} cancer cell population as well as expression of CSC regulators such as Sox2, CD44, Oct4, Notch2more » and β-catenin. Also, treatment with PG sensitized breast cancer cells to anticancer drugs such as cisplatin, etoposide, and taxol as well as to ionizing radiation. Importantly, PG inhibited KRAS and its downstream PI3K/AKT and RAF-1/ERK signaling pathways that regulate the maintenance of CSCs. Taken together, our findings implicate PG as a good candidate to target BCSCs and to prevent the disease relapse. - Highlights: • Phloroglucinol suppresses in vivo tumor formation. • Phloroglucinol sensitizes breast cancer cells to anticancer agents. • Phloroglucinol inhibits breast cancer stem-like cells. • Phloroglucinol inhibits PI3K/AKT and KRAS/RAF/ERK signaling pathways.« less

  9. Dysregulation of the ADAM17/Notch signalling pathways in endometriosis: from oxidative stress to fibrosis.

    PubMed

    González-Foruria, Iñaki; Santulli, Pietro; Chouzenoux, Sandrine; Carmona, Francisco; Chapron, Charles; Batteux, Frédéric

    2017-07-01

    Is oxidative stress associated with the A disintegrin and metalloproteases (ADAM) metallopeptidase domain 17 (ADAM17)/Notch signalling pathway and fibrosis in the development of endometriosis? Oxidative stress is correlated with hyperactivation of the ADAM17/Notch signalling pathway and a consequent increase in fibrosis in patients with endometriosis. It is nowadays accepted that oxidative stress plays an important role in the onset and progression of endometriosis. Oxidative stress is able to induce the synthesis of some members of the 'ADAM' family, such as ADAM17. ADAM17/Notch signalling is dysregulated in other profibrotic and inflammatory diseases. This was a prospective laboratory study conducted in a tertiary-care university hospital between January 2011 and April 2013. We investigated non-pregnant, younger than 42-year-old patients (n = 202) during surgery for a benign gynaecological condition. After complete surgical exploration of the abdominopelvic cavity, 121 women with histologically proven endometriosis and 81 endometriosis-free control women were enrolled. Peritoneal fluid (PF) samples were obtained from all the study participants during surgery in order to detect advanced oxidation protein products (AOPPs) and metalloproteinase activity of ADAM17. Stromal cells from endometrial specimens (n = 8) were obtained from endometrium of control patients (Cs), and from eutopic (Es) and ectopic (Ps) endometrium of patients with deep infiltrating endometriosis (DIE) (n = 8). ADAM17, Notch and the fibrosis markers α-smooth muscle actin (α-SMA) and type-I collagen were assessed using immunoblotting in all the endometrial samples obtained. Additionally, fibrosis was assessed after using Notch cleavage inhibitors (DAPT and FLI-06). Notch and fibrosis were also evaluated after stimulation of stromal endometrial cells with ADAM17 purified protein, increasing concentrations of H2O2 and primary cell culture supernatants. Patients with DIE presented higher PF AOPP and ADAM17 protein levels than controls (P < 0.01 and P < 0.05, respectively). In addition, these two markers were positively correlated (r = 0.614; P < 0.001). At the cellular level, ADAM17 activity was increased in Es and Ps compared to Cs (P < 0.001 and P < 0.01, respectively). Furthermore, Ps presented hyperactivation of Notch signalling (P < 0.05) and augmentation of fibrosis markers (P = 0.009 for α-SMA and P = 0.015 for type-I collagen) compared to controls. The use of DAPT and FLI-06 reduced both fibrosis markers in Ps but not in Cs. Stimulation with ADAM17, H2O2 and Ps supernatant culture significantly increased Notch and fibrosis in both Ps and Cs. N/A. The control group consisted of women who underwent surgery for benign gynaecological conditions, which could lead to biases because some of these conditions may cause alterations in oxidative stress and the ADAM17/Notch pathways. The small sample size of endometrial biopsies used for each group of patients (n = 8) is a limitation of the study, and results should be interpreted with caution. We propose a novel pathway in endometriosis pathogenesis that correlates oxidative stress, hyperactivation of ADAM17/Notch signalling and a consequent increase in fibrosis. This study suggests that Notch signalling plays a key role in the fibrotic processes that take place in ectopic lesions of patients with DIE, as already observed in other pro-fibrotic diseases. This work was supported by grants from University Paris Descartes, INSERM and Fundación Alfonso Martín Escudero. The authors have no competing interests to declare. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  10. Notch signaling: switching an oncogene to a tumor suppressor

    PubMed Central

    Lobry, Camille; Oh, Philmo; Mansour, Marc R.; Look, A. Thomas

    2014-01-01

    The Notch signaling pathway is a regulator of self-renewal and differentiation in several tissues and cell types. Notch is a binary cell-fate determinant, and its hyperactivation has been implicated as oncogenic in several cancers including breast cancer and T-cell acute lymphoblastic leukemia (T-ALL). Recently, several studies also unraveled tumor-suppressor roles for Notch signaling in different tissues, including tissues where it was before recognized as an oncogene in specific lineages. Whereas involvement of Notch as an oncogene in several lymphoid malignancies (T-ALL, B-chronic lymphocytic leukemia, splenic marginal zone lymphoma) is well characterized, there is growing evidence involving Notch signaling as a tumor suppressor in myeloid malignancies. It therefore appears that Notch signaling pathway’s oncogenic or tumor-suppressor abilities are highly context dependent. In this review, we summarize and discuss latest advances in the understanding of this dual role in hematopoiesis and the possible consequences for the treatment of hematologic malignancies. PMID:24608975

  11. The lack of autophagy triggers precocious activation of Notch signaling during Drosophila oogenesis.

    PubMed

    Barth, Julia M I; Hafen, Ernst; Köhler, Katja

    2012-12-05

    The proper balance of autophagy, a lysosome-mediated degradation process, is indispensable for oogenesis in Drosophila. We recently demonstrated that egg development depends on autophagy in the somatic follicle cells (FC), but not in the germline cells (GCs). However, the lack of autophagy only affects oogenesis when FCs are autophagy-deficient but GCs are wild type, indicating that a dysfunctional signaling between soma and germline may be responsible for the oogenesis defects. Thus, autophagy could play an essential role in modulating signal transduction pathways during egg development. Here, we provide further evidence for the necessity of autophagy during oogenesis and demonstrate that autophagy is especially required in subsets of FCs. Generation of autophagy-deficient FCs leads to a wide range of phenotypes that are similar to mutants with defects in the classical cell-cell signaling pathways in the ovary. Interestingly, we observe that loss of autophagy leads to a precocious activation of the Notch pathway in the FCs as monitored by the expression of Cut and Hindsight, two downstream effectors of Notch signaling. Our findings point to an unexpected function for autophagy in the modulation of the Notch signaling pathway during Drosophila oogenesis and suggest a function for autophagy in proper receptor activation. Egg development is affected by an imbalance of autophagy between signal sending (germline) and signal receiving cell (FC), thus the lack of autophagy in the germline is likely to decrease the amount of active ligand and accordingly compensates for increased signaling in autophagy-defective follicle cells.

  12. In patients with chronic aplastic anemia, bone marrow-derived MSCs regulate the Treg/Th17 balance by influencing the Notch/RBP-J/FOXP3/RORγt pathway.

    PubMed

    Li, Hongbo; Wang, Lin; Pang, Yan; Jiang, Zujun; Liu, Zenghui; Xiao, Haowen; Chen, Haijia; Ge, Xiaohu; Lan, Hai; Xiao, Yang

    2017-02-14

    The standard treatment for aplastic anemia (AA) in young patients is a matched sibling hematopoietic stem cell transplant. Transfusion of a chronic AA patient with allogeneic bone marrow-derived mesenchymal stromal cells (BMMSCs) is currently being developed as a cell-based therapy, and the safety and efficacy of such transfusions are being continuously improved. Nevertheless, the mechanisms by which BMMSCs exert their therapeutic effects remain to be elucidated. In this study, mesenchymal stromal cells (MSCs) obtained from bone marrow donors were concentrated and intravenously injected into 15 chronic AA patients who had been refractory to prior immunosuppressive therapy. We showed that BMMSCs modulate the levels of Th1, Th2, Th17 and Treg cells, as well as their related cytokines in chronic AA patients. Furthermore, the percentages of Th1 and Th17 cells among the H-MSCs decreased significantly, while the percentage Treg cells increased. The Notch/RBP-J/FOXP3/RORγt pathway was involved in modulating the Treg/Th17 balance after MSCs were transfused in vitro. Additionally, the role played by transfused MSCs in regulating the Treg/Th17 balance via the Notch/RBP-J/FOXP3/RORγt pathway was further confirmed in an AA mouse model. In summary, in humans with chronic AA, BMMSCs regulate the Treg/Th17 balance by affecting the Notch/RBP-J/FOXP3/RORγt pathway.

  13. The notch pathway is activated in neoplastic progression in esophageal squamous cell carcinoma.

    PubMed

    Lubin, Daniel J; Mick, Rosemarie; Shroff, Stuti G; Stashek, Kristen; Furth, Emma E

    2018-02-01

    The Notch signaling pathway is integral to normal human development and homeostasis and has a deterministic function on cell differentiation. Recent studies suggest aberrant Notch signaling may contribute to neoplastic progression by an increase in stem cell survival, chemoresistance, and the promotion of epithelial-to-mesenchymal transition. The goals of our study were to determine, utilizing quantitative technologies, the expression of activated Notch 1 in esophageal squamous cell carcinoma (SCC) and to determine the relationship between Notch 1 expression and various clinicopathologic parameters. Immunohistochemical staining for Notch intracellular domain (NICD) was performed on 60 consecutive cases of esophageal squamous cell carcinoma, 42 cases of benign esophageal squamous epithelium, and 13 cases of eosinophilic esophagitis diagnosed in our department from 2007 through 2015, and exact nuclear staining and nuclear characteristics were graded using the Vectra imaging system. Clinicopathologic data (gender, age at diagnosis, smoking status, tumor grade, tumor stage, tumor location, and survival) were collected for each SCC case and these were correlated with NICD staining. Cases of esophageal SCC demonstrated significantly higher NICD staining compared to cases of benign and reactive esophageal epithelium (P=.003 and .005, respectively). Among cases of esophageal SCC, nuclear NICD staining was significantly correlated with both tumor grade and stage. Following classification and regression tree analysis, esophageal SCC patients with increased NICD expression were found to be more likely to die from their disease than those with lower levels of expression. Taken together, the findings suggest that increased Notch 1 may contribute to the development and aggressiveness of esophageal SCC. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Dysregulation of Notch and ERα signaling in AhR−/− male mice

    PubMed Central

    Huang, Bo; Butler, Ryan; Miao, Yifei; Dai, Yubing; Wu, Wanfu; Su, Wen; Fujii-Kuriyama, Yoshiaki; Warner, Margaret; Gustafsson, Jan-Åke

    2016-01-01

    The aryl hydrocarbon receptor (AhR) is now recognized as an important physiological regulator in the immune and reproductive systems, and in the development of the liver and vascular system. AhR regulates cell cycle, cell proliferation, and differentiation through interacting with other signaling pathways, like estrogen receptor α (ERα), androgen receptor (AR), and Notch signaling. In the present study, we investigated Notch and estrogen signaling in AhR−/− mice. We found low fertility with degenerative changes in the testes, germ cell apoptosis, and a reduced number of early spermatids. There was no change in aromatase, AR, ERα, or ERβ expression in the testis and no detectable change in serum estrogen levels. However, expression of Notch receptors (Notch1 and Notch3) and their target Hairy and Enhancer of Split homolog 1 (HES1) was reduced. In addition, the testosterone level was slightly reduced in the serum. In the mammary fat pad, AhR appeared to regulate estrogen signaling because, in AhR−/− males, there was significant growth of the mammary ducts with high expression of ERα in the ductal epithelium. The enhanced mammary ductal growth appears to be related to overexpression of ERα accompanied by a high proliferation index, whereas the reduced fertility appears to be related defects in Notch signaling that leads to reduced expression of HES1 and, consequently, early maturation of spermatocytes and a depletion of primary spermatids. Previous reports have indicated that AhR pathway is associated with infertility in men. Our results provide a mechanistic explanation for this defect. PMID:27688768

  15. Combined effects of age and polymorphisms in Notch3 in the pathogenesis of cerebral infarction disease.

    PubMed

    Zhu, Chun-Yu; Wang, Yue; Zeng, Qing-Xuan; Qian, Yu; Li, Huan; Yang, Zi-Xia; Yang, Ya-Mei; Zhang, Qiong; Li, Fei-Feng; Liu, Shu-Lin

    2016-10-01

    Cerebral infarction disease is a severe hypoxic ischemic tissue necrosis in the brain, often leading to long-term functional disability and residual impairments. The Notch signaling pathway plays key roles in proliferation and survival of the stem/progenitor cells of the central and peripheral nervous systems. Notch3 is an important member of the pathway, but the relationships between the genetic abnormalities and cerebral infarction disease still remain unclear. The aim of this work was to evaluate variations in Notch3 gene for their possible associations with the cerebral infarction disease. We sequenced the Notch3 gene for 260 patients with cerebral infarction disease, 300 normal controls with old ages and 300 normal controls with younger ages, and identified the variations. The statistical analyses were conducted using Chi-Square Tests as implemented in SPSS (version 19.0). The Hardy-Weinberg equilibrium test of the population was carried out using the online software OEGE. Six variations, including rs1044116, rs1044009, rs1044006, rs10408676, rs1043996 and rs16980398 within or near the Notch3 gene, were found. The genetic heterozygosity of rs1044116, rs1044009, rs1044006, and rs1043996 was very high, whereas that of rs10408676 and rs16980398 was very low. Statistical analyses showed that rs1044009 and rs1044006 were associated with the risk of cerebral infarction disease in the Chinese Han agedness population. The SNPs rs1044009 and rs1044006 in the Notch3 gene were associated with the risk of cerebral infarction diseases in the Chinese Han agedness population.

  16. Chemotactic Cues for NOTCH1-Dependent Leukemia

    PubMed Central

    Piovan, Erich; Tosello, Valeria; Amadori, Alberto; Zanovello, Paola

    2018-01-01

    The NOTCH signaling pathway is a conserved signaling cascade that regulates many aspects of development and homeostasis in multiple organ systems. Aberrant activity of this signaling pathway is linked to the initiation and progression of several hematological malignancies, exemplified by T-cell acute lymphoblastic leukemia (T-ALL). Interestingly, frequent non-mutational activation of NOTCH1 signaling has recently been demonstrated in B-cell chronic lymphocytic leukemia (B-CLL), significantly extending the pathogenic significance of this pathway in B-CLL. Leukemia patients often present with high-blood cell counts, diffuse disease with infiltration of the bone marrow, secondary lymphoid organs, and diffusion to the central nervous system (CNS). Chemokines are chemotactic cytokines that regulate migration of cells between tissues and the positioning and interactions of cells within tissue. Homeostatic chemokines and their receptors have been implicated in regulating organ-specific infiltration, but may also directly and indirectly modulate tumor growth. Recently, oncogenic NOTCH1 has been shown to regulate infiltration of leukemic cells into the CNS hijacking the CC-chemokine ligand 19/CC-chemokine receptor 7 chemokine axis. In addition, a crucial role for the homing receptor axis CXC-chemokine ligand 12/CXC-chemokine receptor 4 has been demonstrated in leukemia maintenance and progression. Moreover, the CCL25/CCR9 axis has been implicated in the homing of leukemic cells into the gut, particularly in the presence of phosphatase and tensin homolog tumor suppressor loss. In this review, we summarize the latest developments regarding the role of NOTCH signaling in regulating the chemotactic microenvironmental cues involved in the generation and progression of T-ALL and compare these findings to B-CLL. PMID:29666622

  17. Breast cancer stem cells, EMT and therapeutic targets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kotiyal, Srishti; Bhattacharya, Susinjan, E-mail: s.bhattacharya@jiit.ac.in

    Highlights: • Therapeutic targeting or inhibition of the key molecules of signaling pathways can control growth of breast cancer stem cells (BCSCs). • Development of BCSCs also involves miRNA interactions. • Therapeutic achievement can be done by targeting identified targets in the BCSC pathways. - Abstract: A small heterogeneous population of breast cancer cells acts as seeds to induce new tumor growth. These seeds or breast cancer stem cells (BCSCs) exhibit great phenotypical plasticity which allows them to undergo “epithelial to mesenchymal transition” (EMT) at the site of primary tumor and a future reverse transition. Apart from metastasis they aremore » also responsible for maintaining the tumor and conferring it with drug and radiation resistance and a tendency for post-treatment relapse. Many of the signaling pathways involved in induction of EMT are involved in CSC generation and regulation. Here we are briefly reviewing the mechanism of TGF-β, Wnt, Notch, TNF-α, NF-κB, RTK signalling pathways which are involved in EMT as well as BCSCs maintenance. Therapeutic targeting or inhibition of the key/accessory players of these pathways could control growth of BCSCs and hence malignant cancer. Additionally several miRNAs are dysregulated in cancer stem cells indicating their roles as oncogenes or tumor suppressors. This review also lists the miRNA interactions identified in BCSCs and discusses on some newly identified targets in the BCSC regulatory pathways like SHIP2, nicastrin, Pin 1, IGF-1R, pro-inflammatory cytokines and syndecan which can be targeted for therapeutic achievements.« less

  18. Tetrandrine induces autophagy and differentiation by activating ROS and Notch1 signaling in leukemia cells

    PubMed Central

    Liu, Ting; Men, Qiuxu; Wu, Guixian; Yu, Chunrong; Huang, Zan; Liu, Xin; Li, Wenhua

    2015-01-01

    All-trans retinoic acid (ATRA) is a differentiating agent for the treatment of acute promyelocytic leukemia (APL). However, the therapeutic efficacy of ATRA has limitations. Tetrandrine is a traditional Chinese medicinal herb extract with antitumor effects. In this study, we investigated the effects of tetrandrine on human PML-RARα-positive acute promyelocytic leukemia cells. Tetrandrine inhibited tumors in vivo. It induced autophagy and differentiation by triggering ROS generation and activating Notch1 signaling. Tetrandrine induced autophagy and differentiation in M5 type patient primary leukemia cells. The in vivo results indicated that low concentrations of tetrandrine inhibited leukemia cells proliferation and induced autophagy and then facilitated their differentiation, by activating ROS and Notch1 signaling. We suggest that tetrandrine is a potential agent for the treatment of APL by inducing differentiation of leukemia cells. PMID:25797266

  19. Novel candidate genes may be possible predisposing factors revealed by whole exome sequencing in familial esophageal squamous cell carcinoma.

    PubMed

    Forouzanfar, Narjes; Baranova, Ancha; Milanizadeh, Saman; Heravi-Moussavi, Alireza; Jebelli, Amir; Abbaszadegan, Mohammad Reza

    2017-05-01

    Esophageal squamous cell carcinoma is one of the deadliest of all the cancers. Its metastatic properties portend poor prognosis and high rate of recurrence. A more advanced method to identify new molecular biomarkers predicting disease prognosis can be whole exome sequencing. Here, we report the most effective genetic variants of the Notch signaling pathway in esophageal squamous cell carcinoma susceptibility by whole exome sequencing. We analyzed nine probands in unrelated familial esophageal squamous cell carcinoma pedigrees to identify candidate genes. Genomic DNA was extracted and whole exome sequencing performed to generate information about genetic variants in the coding regions. Bioinformatics software applications were utilized to exploit statistical algorithms to demonstrate protein structure and variants conservation. Polymorphic regions were excluded by false-positive investigations. Gene-gene interactions were analyzed for Notch signaling pathway candidates. We identified novel and damaging variants of the Notch signaling pathway through extensive pathway-oriented filtering and functional predictions, which led to the study of 27 candidate novel mutations in all nine patients. Detection of the trinucleotide repeat containing 6B gene mutation (a slice site alteration) in five of the nine probands, but not in any of the healthy samples, suggested that it may be a susceptibility factor for familial esophageal squamous cell carcinoma. Noticeably, 8 of 27 novel candidate gene mutations (e.g. epidermal growth factor, signal transducer and activator of transcription 3, MET) act in a cascade leading to cell survival and proliferation. Our results suggest that the trinucleotide repeat containing 6B mutation may be a candidate predisposing gene in esophageal squamous cell carcinoma. In addition, some of the Notch signaling pathway genetic mutations may act as key contributors to esophageal squamous cell carcinoma.

  20. Notch/Delta signaling constrains reengineering of pro-T cells by PU.1

    PubMed Central

    Franco, Christopher B.; Scripture-Adams, Deirdre D.; Proekt, Irina; Taghon, Tom; Weiss, Angela H.; Yui, Mary A.; Adams, Stephanie L.; Diamond, Rochelle A.; Rothenberg, Ellen V.

    2006-01-01

    PU.1 is essential for early stages of mouse T cell development but antagonizes it if expressed constitutively. Two separable mechanisms are involved: attenuation and diversion. Dysregulated PU.1 expression inhibits pro-T cell survival, proliferation, and passage through β-selection by blocking essential T cell transcription factors, signaling molecules, and Rag gene expression, which expression of a rearranged T cell antigen receptor transgene cannot rescue. However, Bcl2 transgenic cells are protected from this attenuation and may even undergo β-selection, as shown by PU.1 transduction of defined subsets of Bcl2 transgenic fetal thymocytes with differentiation in OP9-DL1 and OP9 control cultures. The outcome of PU.1 expression in these cells depends on Notch/Delta signaling. PU.1 can efficiently divert thymocytes toward a myeloid-like state with multigene regulatory changes, but Notch/Delta signaling vetoes diversion. Gene expression analysis distinguishes sets of critical T lineage regulatory genes with different combinatorial responses to PU.1 and Notch/Delta signals, suggesting particular importance for inhibition of E proteins, Myb, and/or Gfi1 (growth factor independence 1) in diversion. However, Notch signaling only protects against diversion of cells that have undergone T lineage specification after Thy-1 and CD25 up-regulation. The results imply that in T cell precursors, Notch/Delta signaling normally acts to modulate and channel PU.1 transcriptional activities during the stages from T lineage specification until commitment. PMID:16880393

  1. Co-delivery of platinum drug and siNotch1 with micelleplex for enhanced hepatocellular carcinoma therapy.

    PubMed

    Shen, Song; Sun, Chun-Yang; Du, Xiao-Jiao; Li, Hong-Jun; Liu, Yang; Xia, Jin-Xing; Zhu, Yan-Hua; Wang, Jun

    2015-11-01

    As part of HCC tumor cellularity, cancer stem cells (CSCs) are considered a major obstacle to eradicate hepatocellular carcinoma (HCC), which is the third most common cause of cancer-related death worldwide, and the accumulation of chemotherapeutic drug-resistant CSCs invariably accounts for poor prognosis and HCC relapse. In the present study, we explored the efficacy of co-delivery of platinum drug and siRNA targeting Notch1 to treat CSCs-harboring HCC. To overcome the challenging obstacles of platinum drug and siRNA in the systemic administration, we developed a micellar nanoparticle (MNP) to deliver platinum(IV) prodrug and siNotch1, hereafter referred to as (Pt(IV))MNP/siNotch1. We demonstrated that (Pt(IV))MNP/siNotch1 was able to efficiently deliver two drugs into both non-CSCs and CSCs of SMMC7721, a HCC cell line. We further found that siRNA-mediated inhibition of Notch1 suppression can increase the sensitivity of HCC cells to platinum drugs and decrease the percentage of HCC CSCs, and consequently resulting in enhanced proliferation inhibition and apoptosis induction in HCC cells in vitro. Moreover, our results indicated that the combined drug delivery system can remarkably augment drug enrichment in tumor tissues, substantially suppressing the tumor growth while avoiding the accumulation of CSCs in a synergistic manner in the SMMC7721 xenograft model. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Inhibition of Notch3 prevents monocrotaline-induced pulmonary arterial hypertension.

    PubMed

    Zhang, Yonghong; Xie, Xinming; Zhu, Yanting; Liu, Lu; Feng, Wei; Pan, Yilin; Zhai, Cui; Ke, Rui; Li, Shaojun; Song, Yang; Fan, Yuncun; Fan, Fenling; Wang, Xiaochuang; Li, Fengjuan; Li, Manxiang

    2015-01-01

    It has been shown that activation of Notch3 signaling is involved in the development of pulmonary arterial hypertension (PAH) by stimulating pulmonary arteries remodeling, while the molecular mechanisms underlying this are still largely unknown. The aims of this study are to address these issues. Monocrotaline dramatically increased right ventricle systolic pressure to 39.0 ± 2.6 mmHg and right ventricle hypertrophy index to 53.4 ± 5.3% (P < 0.05 versus control) in rats, these were accompanied with significantly increased proliferation and reduced apoptosis of pulmonary vascular cells as well as pulmonary arteries remodeling. Treatment of PAH model with specific Notch inhibitor DAPT significantly reduced right ventricle systolic pressure to 26.6 ± 1.3 mmHg and right ventricle hypertrophy index to 33.5 ± 2.6% (P < 0.05 versus PAH), suppressed proliferation and enhanced apoptosis of pulmonary vascular cells as well as inhibited pulmonary arteries remodeling. Our results further indicated that level of Notch3 protein and NICD3 were increased in MCT-induced model of PAH, this was accompanied with elevation of Skp2 and Hes1 protein level and reduction of P27Kip1. Administration of rats with DAPT-prevented MCT induced these changes. Our results suggest that Notch3 signaling activation stimulated pulmonary vascular cells proliferation by Skp2-and Hes1-mediated P27Kip1 reduction, and Notch3 might be a new target to treat PAH.

  3. Notch Signaling and Alloreactivity.

    PubMed

    Radojcic, Vedran; Maillard, Ivan

    2016-12-01

    Solid organ and allogeneic hematopoietic cell transplantation have become standard therapeutic interventions that save patient lives and improve quality of life. Our enhanced understanding of transplantation immunobiology has refined clinical management and improved outcomes. However, organ rejection and graft-versus-host disease remain major obstacles to the broader successful application of these therapeutic procedures. Notch signaling regulates multiple aspects of adaptive and innate immunity. Preclinical studies identified Notch signaling as a promising target in autoimmune diseases, as well as after allogeneic hematopoietic cell and solid organ transplantation. Notch was found to be a central regulator of alloreactivity across clinically relevant models of transplantation. Notch inhibition in T cells prevented graft-versus-host disease and organ rejection, establishing organ tolerance by skewing CD4 T helper polarization away from a proinflammatory response toward suppressive regulatory T cells. Notch ligand blockade also dampened alloantibody deposition and prevented chronic rejection through humoral mechanisms. Toxicities of systemic Notch blockade were observed with γ-secretase inhibitors in preclinical and early clinical trials across different indications, but they did not arise upon preclinical targeting of Delta-like Notch ligands, a strategy sufficient to confer full benefits of Notch ablation in T cell alloimmunity. Because multiple clinical grade reagents have been developed to target individual Notch ligands and receptors, the benefits of Notch blockade in transplantation are calling for translation of preclinical findings into human transplantation medicine.

  4. Novel Roles for Notch3 and Notch4 Receptors in Gene Expression and Susceptibility to Ozone-Induced Lung Inflammation in Mice

    PubMed Central

    McCaw, Zachary; Gladwell, Wesley; Trivedi, Shweta; Bushel, Pierre R.; Kleeberger, Steven R.

    2015-01-01

    Background Ozone is a highly toxic air pollutant and global health concern. Mechanisms of genetic susceptibility to ozone-induced lung inflammation are not completely understood. We hypothesized that Notch3 and Notch4 are important determinants of susceptibility to ozone-induced lung inflammation. Methods Wild-type (WT), Notch3 (Notch3–/–), and Notch4 (Notch4–/–) knockout mice were exposed to ozone (0.3 ppm) or filtered air for 6–72 hr. Results Relative to air-exposed controls, ozone increased bronchoalveolar lavage fluid (BALF) protein, a marker of lung permeability, in all genotypes, but significantly greater concentrations were found in Notch4–/– compared with WT and Notch3–/– mice. Significantly greater mean numbers of BALF neutrophils were found in Notch3–/– and Notch4–/– mice compared with WT mice after ozone exposure. Expression of whole lung Tnf was significantly increased after ozone in Notch3–/– and Notch4–/– mice, and was significantly greater in Notch3–/– compared with WT mice. Statistical analyses of the transcriptome identified differentially expressed gene networks between WT and knockout mice basally and after ozone, and included Trim30, a member of the inflammasome pathway, and Traf6, an inflammatory signaling member. Conclusions These novel findings are consistent with Notch3 and Notch4 as susceptibility genes for ozone-induced lung injury, and suggest that Notch receptors protect against innate immune inflammation. Citation Verhein KC, McCaw Z, Gladwell W, Trivedi S, Bushel PR, Kleeberger SR. 2015. Novel roles for Notch3 and Notch4 receptors in gene expression and susceptibility to ozone-induced lung inflammation in mice. Environ Health Perspect 123:799–805; http://dx.doi.org/10.1289/ehp.1408852 PMID:25658374

  5. Reciprocal Signaling between the Ectoderm and a Mesendodermal Left-Right Organizer Directs Left-Right Determination in the Sea Urchin Embryo

    PubMed Central

    Bessodes, Nathalie; Haillot, Emmanuel; Duboc, Véronique; Röttinger, Eric; Lahaye, François; Lepage, Thierry

    2012-01-01

    During echinoderm development, expression of nodal on the right side plays a crucial role in positioning of the rudiment on the left side, but the mechanisms that restrict nodal expression to the right side are not known. Here we show that establishment of left-right asymmetry in the sea urchin embryo relies on reciprocal signaling between the ectoderm and a left-right organizer located in the endomesoderm. FGF/ERK and BMP2/4 signaling are required to initiate nodal expression in this organizer, while Delta/Notch signaling is required to suppress formation of this organizer on the left side of the archenteron. Furthermore, we report that the H+/K+-ATPase is critically required in the Notch signaling pathway upstream of the S3 cleavage of Notch. Our results identify several novel players and key early steps responsible for initiation, restriction, and propagation of left-right asymmetry during embryogenesis of a non-chordate deuterostome and uncover a functional link between the H+/K+-ATPase and the Notch signaling pathway. PMID:23271979

  6. A novel population of local pericyte precursor cells in tumor stroma that require Notch signaling for differentiation.

    PubMed

    Patenaude, Alexandre; Woerher, Stefan; Umlandt, Patricia; Wong, Fred; Ibrahim, Rawa; Kyle, Alastair; Unger, Sandy; Fuller, Megan; Parker, Jeremy; Minchinton, Andrew; Eaves, Connie J; Karsan, Aly

    2015-09-01

    Pericytes are perivascular support cells, the origin of which in tumor tissue is not clear. Recently, we identified a Tie1(+) precursor cell that differentiates into vascular smooth muscle, in a Notch-dependent manner. To understand the involvement of Notch in the ontogeny of tumor pericytes we used a novel flow immunophenotyping strategy to define CD146(+)/CD45(-)/CD31(-/lo) pericytes in the tumor stroma. This strategy combined with ex vivo co-culture experiments identified a novel pericyte progenitor cell population defined as Sca1(hi)/CD146(-)/CD45(-)/CD31(-). The differentiation of these progenitor cells was stimulated by co-culture with endothelial cells. Overexpression of the Notch ligand Jagged1 in endothelial cells further stimulated the differentiation of Sca1(hi)/CD146(-)/CD45(-)/CD31(-) cells into pericytes, while inhibition of Notch signaling with a γ-secretase inhibitor reduced this differentiation. However, Notch inhibition specifically in Tie1-expressing cells did not change the abundance of pericytes in tumors, suggesting that the pericyte precursor is distinct from the vascular smooth muscle cell precursor. Transplant experiments showed that the bone marrow contributes minimally to tumor pericytes. Immunophenotyping revealed that Sca1(hi)/CD146(-)/CD45(-)/CD31(-) cells have greater potential to differentiate into pericytes and have increased expression of classic mesenchymal stem cell markers (CD13, CD44, Nt5e and Thy-1) compared to Sca1(-/lo)/CD146(-)/CD45(-)/CD31(-) cells. Our results suggest that a local Sca1(hi)/CD146(-)/CD45(-)/CD31(-) pericyte progenitor resides in the tumor microenvironment and requires Notch signaling for differentiation into mature pericytes. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Differential microRNA expression in the prefrontal cortex of mouse offspring induced by glyphosate exposure during pregnancy and lactation.

    PubMed

    Ji, Hua; Xu, Linhao; Wang, Zheng; Fan, Xinli; Wu, Lihui

    2018-03-01

    Glyphosate is the active ingredient in numerous herbicide formulations. The role of glyphosate in neurotoxicity has been reported in human and animal models. However, the detailed mechanism of the role of glyphosate in neuronal development remains unknown. Recently, several studies have reported evidence linking neurodevelopmental disorders (NDDs) with gestational glyphosate exposure. The current group previously identified microRNAs (miRNAs) that are associated with the etiology of NDDs, but their expression levels in the developing brain following glyphosate exposure have not been characterized. In the present study, miRNA expression patterns were evaluated in the prefrontal cortex (PFC) of 28 postnatal day mouse offspring following glyphosate exposure during pregnancy and lactation. An miRNA microarray detected 55 upregulated and 19 downregulated miRNAs in the PFC of mouse offspring, and 20 selected deregulated miRNAs were further evaluated by quantitative polymerase chain reaction (PCR). A total of 11 targets of these selected deregulated miRNAs were analyzed using bioinformatics. Gene Ontology (GO) terms associated with the relevant miRNAs included neurogenesis (GO:0050769), neuron differentiation (GO:0030182) and brain development (GO:0007420). The genes Cdkn1a, Numbl, Notch1, Fosl1 and Lef1 are involved in the Wnt and Notch signaling pathways, which are closely associated with neural development. PCR arrays for the mouse Wnt and Notch signaling pathways were used to validate the effects of glyphosate on the expression pattern of genes involved in the Wnt and Notch pathways. Nr4a2 and Wnt7b were downregulated, while Dkk1, Dixdc1, Runx1, Shh, Lef-1 and Axin2 were upregulated in the PFC of mice offspring following glyphosate exposure during pregnancy and lactation. These results indicated abnormalities of the Wnt/β-catenin and Notch pathways. These findings may be of particular interest for understanding the mechanism of glyphosate-induced neurotoxicity, as well as helping to clarify the association between glyphosate and NDDs.

  8. Differential microRNA expression in the prefrontal cortex of mouse offspring induced by glyphosate exposure during pregnancy and lactation

    PubMed Central

    Ji, Hua; Xu, Linhao; Wang, Zheng; Fan, Xinli; Wu, Lihui

    2018-01-01

    Glyphosate is the active ingredient in numerous herbicide formulations. The role of glyphosate in neurotoxicity has been reported in human and animal models. However, the detailed mechanism of the role of glyphosate in neuronal development remains unknown. Recently, several studies have reported evidence linking neurodevelopmental disorders (NDDs) with gestational glyphosate exposure. The current group previously identified microRNAs (miRNAs) that are associated with the etiology of NDDs, but their expression levels in the developing brain following glyphosate exposure have not been characterized. In the present study, miRNA expression patterns were evaluated in the prefrontal cortex (PFC) of 28 postnatal day mouse offspring following glyphosate exposure during pregnancy and lactation. An miRNA microarray detected 55 upregulated and 19 downregulated miRNAs in the PFC of mouse offspring, and 20 selected deregulated miRNAs were further evaluated by quantitative polymerase chain reaction (PCR). A total of 11 targets of these selected deregulated miRNAs were analyzed using bioinformatics. Gene Ontology (GO) terms associated with the relevant miRNAs included neurogenesis (GO:0050769), neuron differentiation (GO:0030182) and brain development (GO:0007420). The genes Cdkn1a, Numbl, Notch1, Fosl1 and Lef1 are involved in the Wnt and Notch signaling pathways, which are closely associated with neural development. PCR arrays for the mouse Wnt and Notch signaling pathways were used to validate the effects of glyphosate on the expression pattern of genes involved in the Wnt and Notch pathways. Nr4a2 and Wnt7b were downregulated, while Dkk1, Dixdc1, Runx1, Shh, Lef-1 and Axin2 were upregulated in the PFC of mice offspring following glyphosate exposure during pregnancy and lactation. These results indicated abnormalities of the Wnt/β-catenin and Notch pathways. These findings may be of particular interest for understanding the mechanism of glyphosate-induced neurotoxicity, as well as helping to clarify the association between glyphosate and NDDs. PMID:29467848

  9. Repression of Ccr9 transcription in mouse T lymphocyte progenitors by the Notch signaling pathway.

    PubMed

    Krishnamoorthy, Veena; Carr, Tiffany; de Pooter, Renee F; Emanuelle, Akinola Olumide; Akinola, Emanuelle Olumide; Gounari, Fotini; Kee, Barbara L

    2015-04-01

    The chemokine receptor CCR9 controls the immigration of multipotent hematopoietic progenitor cells into the thymus to sustain T cell development. Postimmigration, thymocytes downregulate CCR9 and migrate toward the subcapsular zone where they recombine their TCR β-chain and γ-chain gene loci. CCR9 is subsequently upregulated and participates in the localization of thymocytes during their selection for self-tolerant receptor specificities. Although the dynamic regulation of CCR9 is essential for early T cell development, the mechanisms controlling CCR9 expression have not been determined. In this article, we show that key regulators of T cell development, Notch1 and the E protein transcription factors E2A and HEB, coordinately control the expression of Ccr9. E2A and HEB bind at two putative enhancers upstream of Ccr9 and positively regulate CCR9 expression at multiple stages of T cell development. In contrast, the canonical Notch signaling pathway prevents the recruitment of p300 to the putative Ccr9 enhancers, resulting in decreased acetylation of histone H3 and a failure to recruit RNA polymerase II to the Ccr9 promoter. Although Notch signaling modestly modulates the binding of E proteins to one of the two Ccr9 enhancers, we found that Notch signaling represses Ccr9 in T cell lymphoma lines in which Ccr9 transcription is independent of E protein function. Our data support the hypothesis that activation of Notch1 has a dominant-negative effect on Ccr9 transcription and that Notch1 and E proteins control the dynamic expression of Ccr9 during T cell development. Copyright © 2015 by The American Association of Immunologists, Inc.

  10. Acquisition of Epithelial-Mesenchymal Transition phenotype of gemcitabine-resistant pancreatic cancer cells is linked with activation of Notch signaling pathway

    PubMed Central

    Wang, Zhiwei; Li, Yiwei; Kong, Dejuan; Banerjee, Sanjeev; Ahmad, Aamir; Azmi, Asfar Sohail; Ali, Shadan; Abbruzzese, James L.; Gallick, Gary E.; Sarkar, Fazlul H

    2009-01-01

    Despite rapid advances in many fronts, pancreatic cancer (PC) remains one of the most difficult human malignancies to treat, in part due to de novo and acquired chemo- and radio-resistance. Gemcitabine alone or in combination with other conventional therapeutics is the standard of care for the treatment of advanced PC without any significant improvement in the overall survival of patients diagnosed with this deadly disease. Previous studies have shown that PC cells that are gemcitabine-resistant (GR) acquired epithelial-mesenchymal transition (EMT) phenotype which is reminiscent of “cancer stem-like cells (CSC)”; however the molecular mechanism that led to EMT phenotype has not been fully investigated. The present study demonstrates that Notch-2 and its ligand Jagged-1 are highly up-regulated in GR cells, which is consistent with the role of Notch signaling pathway in the acquisition of EMT and CSC phenotype. We also found that the down-regulation of Notch signaling was associated with decreased invasive behavior of GR cells. Moreover, down-regulation of Notch signaling by siRNA approach led to partial reversal of the EMT phenotype, resulting in the mesenchymal-epithelial transition (MET), which was associated with decreased expression of vimentin, ZEB1, Slug, Snail and NF-κB. These results provide molecular evidence showing that the activation of Notch signaling is mechanistically linked with chemo-resistance phenotype (EMT phenotype) of PC cells, suggesting that the inactivation of Notch signaling by novel strategies could be a potential targeted therapeutic approach for overcoming chemo-resistance toward the prevention of tumor progression and/or treatment of metastatic PC. PMID:19276344

  11. Muscle contraction is required to maintain the pool of muscle progenitors via YAP and NOTCH during fetal myogenesis

    PubMed Central

    Esteves de Lima, Joana; Bonnin, Marie-Ange; Birchmeier, Carmen; Duprez, Delphine

    2016-01-01

    The importance of mechanical activity in the regulation of muscle progenitors during chick development has not been investigated. We show that immobilization decreases NOTCH activity and mimics a NOTCH loss-of-function phenotype, a reduction in the number of muscle progenitors and increased differentiation. Ligand-induced NOTCH activation prevents the reduction of muscle progenitors and the increase of differentiation upon immobilization. Inhibition of NOTCH ligand activity in muscle fibers suffices to reduce the progenitor pool. Furthermore, immobilization reduces the activity of the transcriptional co-activator YAP and the expression of the NOTCH ligand JAG2 in muscle fibers. YAP forced-activity in muscle fibers prevents the decrease of JAG2 expression and the number of PAX7+ cells in immobilization conditions. Our results identify a novel mechanism acting downstream of muscle contraction, where YAP activates JAG2 expression in muscle fibers, which in turn regulates the pool of fetal muscle progenitors via NOTCH in a non-cell-autonomous manner. DOI: http://dx.doi.org/10.7554/eLife.15593.001 PMID:27554485

  12. Characterization of Aes nuclear foci in colorectal cancer cells.

    PubMed

    Itatani, Yoshiro; Sonoshita, Masahiro; Kakizaki, Fumihiko; Okawa, Katsuya; Stifani, Stefano; Itoh, Hideaki; Sakai, Yoshiharu; Taketo, M Mark

    2016-01-01

    Amino-terminal enhancer of split (Aes) is a member of Groucho/Transducin-like enhancer (TLE) family. Aes is a recently found metastasis suppressor of colorectal cancer (CRC) that inhibits Notch signalling, and forms nuclear foci together with TLE1. Although some Notch-associated proteins are known to form subnuclear bodies, little is known regarding the dynamics or functions of these structures. Here, we show that Aes nuclear foci in CRC observed under an electron microscope are in a rather amorphous structure, lacking surrounding membrane. Investigation of their behaviour during the cell cycle by time-lapse cinematography showed that Aes nuclear foci dissolve during mitosis and reassemble after completion of cytokinesis. We have also found that heat shock cognate 70 (HSC70) is an essential component of Aes foci. Pharmacological inhibition of the HSC70 ATPase activity with VER155008 reduces Aes focus formation. These results provide insight into the understanding of Aes-mediated inhibition of Notch signalling. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  13. Complementary Proteome and Transcriptome Profiling in Developing Grains of a Notched-Belly Rice Mutant Reveals Key Pathways Involved in Chalkiness Formation

    PubMed Central

    Lin, Zhaomiao; Wang, Zunxin; Zhang, Xincheng; Li, Ganghua; Wang, Shaohua; Ding, Yanfeng

    2017-01-01

    Rice grain chalkiness is a highly complex trait involved in multiple metabolic pathways and controlled by polygenes and growth conditions. To uncover novel aspects of chalkiness formation, we performed an integrated profiling of gene activity in the developing grains of a notched-belly rice mutant. Using exhaustive tandem mass spectrometry-based shotgun proteomics and whole-genome RNA sequencing to generate a nearly complete catalog of expressed mRNAs and proteins, we reliably identified 38,476 transcripts and 3,840 proteins. Comparison between the translucent part and chalky part of the notched-belly grains resulted in only a few differently express genes (240) and differently express proteins (363), thus making it possible to focus on ‘core’ genes or common pathways. Several novel key pathways were identified as of relevance to chalkiness formation, in particular the shift of C and N metabolism, the down-regulation of ribosomal proteins and the resulting low abundance of storage proteins especially the 13 kDa prolamin subunit, and the suppressed photosynthetic capacity in the pericarp of the chalky part. Further, genes and proteins as transporters for carbohydrates, amino acid/peptides, proteins, lipids and inorganic ions showed an increasing expression pattern in the chalky part of the notched-belly grains. Similarly, transcripts and proteins of receptors for auxin, ABA, ethylene and brassinosteroid were also up-regulated. In summary, this joint analysis of transcript and protein profiles provides a comprehensive reference map of gene activity regarding the physiological state in the chalky endosperm. PMID:28158863

  14. Adult epidermal Notch activity induces dermal accumulation of T cells and neural crest derivatives through upregulation of jagged 1.

    PubMed

    Ambler, Carrie A; Watt, Fiona M

    2010-11-01

    Notch signalling regulates epidermal differentiation and tumour formation via non-cell autonomous mechanisms that are incompletely understood. This study shows that epidermal Notch activation via a 4-hydroxy-tamoxifen-inducible transgene caused epidermal thickening, focal detachment from the underlying dermis and hair clumping. In addition, there was dermal accumulation of T lymphocytes and stromal cells, some of which localised to the blisters at the epidermal-dermal boundary. The T cell infiltrate was responsible for hair clumping but not for other Notch phenotypes. Notch-induced stromal cells were heterogeneous, expressing markers of neural crest, melanocytes, smooth muscle and peripheral nerve. Although Slug1 expression was expanded in the epidermis, the stromal cells did not arise through epithelial-mesenchymal transition. Epidermal Notch activation resulted in upregulation of jagged 1 in both epidermis and dermis. When Notch was activated in the absence of epidermal jagged 1, jagged 1 was not upregulated in the dermis, and epidermal thickening, blister formation, accumulation of T cells and stromal cells were inhibited. Gene expression profiling revealed that epidermal Notch activation resulted in upregulation of several growth factors and cytokines, including TNFα, the expression of which was dependent on epidermal jagged 1. We conclude that jagged 1 is a key mediator of non-cell autonomous Notch signalling in skin.

  15. Synergistic suppression of human breast cancer cells by combination of plumbagin and zoledronic acid In vitro.

    PubMed

    Qiao, Han; Wang, Ting-yu; Yan, Wei; Qin, An; Fan, Qi-ming; Han, Xiu-guo; Wang, Yu-gang; Tang, Ting-ting

    2015-09-01

    Zoledronic acid (ZA), a bisphosphonate, is currently used in combination with chemotherapeutic agents to suppress breast cancer cell proliferation or breast cancer-induced osteolysis. The aim of this study was to investigate the effects of ZA combined with a natural anticancer compound plumbagin (PL) against human breast cancer cells in vitro. Human breast cancer MDA-MB-231SArfp cells were treated with ZA, PL or a combination of ZA and PL. The cell growth, apoptosis and migration were evaluated using CCK-8 assay, flow cytometry and transwell assay, respectively. The expression of apoptosis-related proteins was measured using real-time PCR and Western blotting. Synergism was evaluated using Compusyn software, and the combination index (CI) and drug reduction index (DRI) values were determined. PL or ZA alone caused mild cytotoxicity (the IC50 value at 24 h was 12.18 and above 100 μmol/L, respectively). However, the combination of ZA and PL caused a synergistic cytotoxicity (CI=0.26). The DRI values also showed a synergistic effect between PL and ZA, with actual values of 5.52 and 3.59, respectively. Furthermore, PL and ZA synergistically induced apoptosis and inhibited migration of the breast cancer cells. Moreover, the combination of ZA and PL decreased the expression of Notch-1, cleaved PARP, Bcl-2 and Bcl-xl, and increased the expression of cleaved caspase-3, CDKN1A and ID1. When the breast cancer cells were transfected with specific siRNA against Notch-1, the combination of ZA and PL markedly increased the expression of Bcl-2. Combination of ZA and PL synergistically suppresses human breast cancer MDA-MB-231SArfp cells in vitro. PL can inhibit ZA-induced activation of the Notch-1 signaling pathway and subsequently reduce the expression of Bcl-2, thus potentiating cancer cell apoptosis.

  16. Notch signaling modulates sleep homeostasis and learning after sleep deprivation in Drosophila.

    PubMed

    Seugnet, Laurent; Suzuki, Yasuko; Merlin, Gabriel; Gottschalk, Laura; Duntley, Stephen P; Shaw, Paul J

    2011-05-24

    The role of the transmembrane receptor Notch in the adult brain is poorly understood. Here, we provide evidence that bunched, a negative regulator of Notch, is involved in sleep homeostasis. Genetic evidence indicates that interfering with bunched activity in the mushroom bodies (MBs) abolishes sleep homeostasis. Combining bunched and Delta loss-of-function mutations rescues normal homeostasis, suggesting that Notch signaling may be involved in regulating sensitivity to sleep loss. Preventing the downregulation of Delta by overexpressing a wild-type transgene in MBs reduces sleep homeostasis and, importantly, prevents learning impairments induced by sleep deprivation. Similar resistance to sleep loss is observed with Notch(spl-1) gain-of-function mutants. Immunohistochemistry reveals that the Notch receptor is expressed in glia, whereas Delta is localized in neurons. Importantly, the expression in glia of the intracellular domain of Notch, a dominant activated form of the receptor, is sufficient to prevent learning deficits after sleep deprivation. Together, these results identify a novel neuron-glia signaling pathway dependent on Notch and regulated by bunched. These data highlight the emerging role of neuron-glia interactions in regulating both sleep and learning impairments associated with sleep loss. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Monitoring Notch Signaling-Associated Activation of Stem Cell Niches within Injured Dental Pulp

    PubMed Central

    Mitsiadis, Thimios A.; Catón, Javier; Pagella, Pierfrancesco; Orsini, Giovanna; Jimenez-Rojo, Lucia

    2017-01-01

    Dental pulp stem/progenitor cells guarantee tooth homeostasis, repair and regeneration throughout life. The decision between renewal and differentiation of these cells is influenced by physical and molecular interactions with stromal cells and extracellular matrix molecules forming the specialized microenvironment of dental pulp stem cell niches. Here we study the activation of putative pulp niches after tooth injury through the upregulation of Notch signaling pathway. Notch1, Notch2, and Notch3 molecules were used as markers of dental pulp stem/progenitor cells. Upon dental injury, Notch1 and Notch3 are detected in cells related to vascular structures suggesting a role of these proteins in the activation of specific pulpal perivascular niches. In contrast, a population of Notch2-positive cells that are actively proliferative is observed in the apical part of the pulp. Kinetics of these cells is followed up with a lipophilic DiI labeling, showing that apical pulp cells migrate toward the injury site where dynamic regenerative/repair events occur. The knowledge of the activation and regulation of dental pulp stem/progenitor cells within their niches in pathologic conditions may be helpful for the realization of innovative dental treatments in the near future. PMID:28611689

  18. NOTCH signaling in skeletal progenitors is critical for fracture repair

    PubMed Central

    Wang, Cuicui; Inzana, Jason A.; Mirando, Anthony J.; Liu, Zhaoyang; Shen, Jie; O’Keefe, Regis J.; Awad, Hani A.; Hilton, Matthew J.

    2016-01-01

    Fracture nonunions develop in 10%–20% of patients with fractures, resulting in prolonged disability. Current data suggest that bone union during fracture repair is achieved via proliferation and differentiation of skeletal progenitors within periosteal and soft tissues surrounding bone, while bone marrow stromal/stem cells (BMSCs) and other skeletal progenitors may also contribute. The NOTCH signaling pathway is a critical maintenance factor for BMSCs during skeletal development, although the precise role for NOTCH and the requisite nature of BMSCs following fracture is unknown. Here, we evaluated whether NOTCH and/or BMSCs are required for fracture repair by performing nonstabilized and stabilized fractures on NOTCH-deficient mice with targeted deletion of RBPjk in skeletal progenitors, maturing osteoblasts, and committed chondrocytes. We determined that removal of NOTCH signaling in BMSCs and subsequent depletion of this population result in fracture nonunion, as the fracture repair process was normal in animals harboring either osteoblast- or chondrocyte-specific deletion of RBPjk. Together, this work provides a genetic model of a fracture nonunion and demonstrates the requirement for NOTCH and BMSCs in fracture repair, irrespective of fracture stability and vascularity. PMID:26950423

  19. PKCθ links proximal T cell and Notch signaling through localized regulation of the actin cytoskeleton

    PubMed Central

    Britton, Graham J; Ambler, Rachel; Clark, Danielle J; Hill, Elaine V; Tunbridge, Helen M; McNally, Kerrie E; Burton, Bronwen R; Butterweck, Philomena; Sabatos-Peyton, Catherine; Hampton-O’Neil, Lea A; Verkade, Paul; Wülfing, Christoph; Wraith, David Cameron

    2017-01-01

    Notch is a critical regulator of T cell differentiation and is activated through proteolytic cleavage in response to ligand engagement. Using murine myelin-reactive CD4 T cells, we demonstrate that proximal T cell signaling modulates Notch activation by a spatiotemporally constrained mechanism. The protein kinase PKCθ is a critical mediator of signaling by the T cell antigen receptor and the principal costimulatory receptor CD28. PKCθ selectively inactivates the negative regulator of F-actin generation, Coronin 1A, at the center of the T cell interface with the antigen presenting cell (APC). This allows for effective generation of the large actin-based lamellum required for recruitment of the Notch-processing membrane metalloproteinase ADAM10. Such enhancement of Notch activation is critical for efficient T cell proliferation and Th17 differentiation. We reveal a novel mechanism that, through modulation of the cytoskeleton, controls Notch activation at the T cell:APC interface thereby linking T cell receptor and Notch signaling pathways. DOI: http://dx.doi.org/10.7554/eLife.20003.001 PMID:28112644

  20. RBPJ maintains brain tumor–initiating cells through CDK9-mediated transcriptional elongation

    PubMed Central

    Xie, Qi; Wu, Qiulian; Kim, Leo; Miller, Tyler E.; Liau, Brian B.; Mack, Stephen C.; Yang, Kailin; Factor, Daniel C.; Fang, Xiaoguang; Huang, Zhi; Zhou, Wenchao; Alazem, Kareem; Wang, Xiuxing; Bernstein, Bradley E.; Bao, Shideng; Rich, Jeremy N.

    2016-01-01

    Glioblastomas co-opt stem cell regulatory pathways to maintain brain tumor–initiating cells (BTICs), also known as cancer stem cells. NOTCH signaling has been a molecular target in BTICs, but NOTCH antagonists have demonstrated limited efficacy in clinical trials. Recombining binding protein suppressor of hairless (RBPJ) is considered a central transcriptional mediator of NOTCH activity. Here, we report that pharmacologic NOTCH inhibitors were less effective than targeting RBPJ in suppressing tumor growth. While NOTCH inhibitors decreased canonical NOTCH gene expression, RBPJ regulated a distinct profile of genes critical to BTIC stemness and cell cycle progression. RBPJ was preferentially expressed by BTICs and required for BTIC self-renewal and tumor growth. MYC, a key BTIC regulator, bound the RBPJ promoter and treatment with a bromodomain and extraterminal domain (BET) family bromodomain inhibitor decreased MYC and RBPJ expression. Proteomic studies demonstrated that RBPJ binds CDK9, a component of positive transcription elongation factor b (P-TEFb), to target gene promoters, enhancing transcriptional elongation. Collectively, RBPJ links MYC and transcriptional control through CDK9, providing potential nodes of fragility for therapeutic intervention, potentially distinct from NOTCH. PMID:27322055

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