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1.
Dig Dis Sci ; 66(1): 143-150, 2021 01.
Article in English | MEDLINE | ID: mdl-32144602

ABSTRACT

BACKGROUND: The transformation of hepatic stellate cells (HSCs) into collagen-producing myofibroblasts is a key event in hepatic fibrogenesis. Recent studies have shown that microRNAs (miRNAs) play a critical role in the transformation of HSCs. However, the function of miR-489-3p in liver fibrosis remains unclear. METHODS: Here, we detected the levels of miR-489-3p and jagged canonical Notch ligand 1 (JAG1) in liver fibrosis by using CCl4-treated rats as an in vivo model and transforming growth factor-beta 1 (TGF-ß1)-treated HSC cell lines LX-2 and HSC-T6 as in vitro models. The expression of profibrotic markers was affected by transfecting LX-2 cells with either miR-489-3p mimic or si-JAG1. A dual-luciferase reporter assay was carried out to study the interaction of JAG1 with miR-489-3p. RESULTS: We found that miR-489-3p was remarkably decreased while JAG1 was increased in liver fibrosis models both in vivo and in vitro. Overexpression of miR-489-3p reduced the expression of profibrotic markers and the activation of LX-2 cells induced by TGF-ß1. Moreover, miR-489-3p decreased the expression of jagged canonical Notch ligand 1 (JAG1) in LX-2 cells by interacting with its 3'-UTR. As JAG1 is a Notch ligand, decreased JAG1 by miR-489-3p inhibited the Notch signaling pathway. Moreover, the downregulation of JAG1 inhibited the expression of fibrotic markers. CONCLUSION: Our results indicate that miR-489-3p can inhibit HSC activation by inhibiting the JAG1/Notch3 signaling pathway.


Subject(s)
Hepatic Stellate Cells/metabolism , Jagged-1 Protein/biosynthesis , Liver Cirrhosis/metabolism , MicroRNAs/biosynthesis , Receptor, Notch3/biosynthesis , Signal Transduction/physiology , Animals , Cell Line , Hepatic Stellate Cells/pathology , Humans , Jagged-1 Protein/antagonists & inhibitors , Liver Cirrhosis/pathology , Male , Rats , Rats, Sprague-Dawley , Receptor, Notch3/antagonists & inhibitors
2.
Cell Oncol (Dordr) ; 43(5): 821-834, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32483746

ABSTRACT

PURPOSE: Pancreatic cancer is one of the most aggressive cancers. Preclinical and clinical data indicate that Notch 1 ligand jagged1 (JAG1) plays a pro-oncogenic role in several malignant cancers. As yet, however, the role of JAG1 in pancreatic cancer is poorly understood. The objective of the present study was to investigate JAG1 as a therapeutic target in human pancreatic cancer. METHODS: Expression levels of Notch signaling molecules were assessed using GEO datasets and Western blot analysis, respectively. Anti-tumor effects following JAG1 silencing were evaluated using in vitro and in vivo assays. Prognostic implications were assessed using GEO datasets. RESULTS: Using GEO datasets and Western blot analysis we detected significantly higher JAG1 mRNA and protein expression levels in pancreatic cancer compared to normal pancreatic tissues. JAG1 silencing significantly restrained the growth, migration and invasion of pancreatic cancer cells through the induction of apoptosis and blockade of various kinases independent of the Notch1 pathway. Combined JAG1 silencing and gemcitabine treatment showed synergistic anti-viability effects in human pancreatic cancer cells. JAG1 silencing also resulted in significant anti-cancer effects in vivo and high JAG1 expression was found to be associated with an adverse prognosis in pancreatic cancer patients. CONCLUSIONS: From our data we conclude that JAG1 may be a promising therapeutic target in pancreatic cancer.


Subject(s)
Gene Expression Regulation, Neoplastic , Jagged-1 Protein/genetics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Deoxycytidine/analogs & derivatives , Deoxycytidine/pharmacology , Deoxycytidine/therapeutic use , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic/drug effects , Gene Silencing , Humans , Jagged-1 Protein/antagonists & inhibitors , Jagged-1 Protein/metabolism , Mice, Inbred BALB C , Mice, Nude , Pancreatic Neoplasms/drug therapy , Prognosis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction , Gemcitabine
3.
FEBS Open Bio ; 10(6): 1082-1095, 2020 06.
Article in English | MEDLINE | ID: mdl-32274896

ABSTRACT

Notch signaling and nuclear receptor PPARγ are involved in macrophage polarization, but cross talk between them has not been reported in macrophages. In this study, the effect of Notch signaling on PPARγ in IL-4-stimulated human macrophages (M(IL-4)) was investigated using THP-1-derived macrophages and human monocyte-derived macrophages as models. Human M(IL-4) increased the expression of JAGGED1 and activated Notch signaling. Overexpression of Notch1 intracellular domain (NIC1) increased PPARγ expression, while inhibiting Notch signaling decreased PPARγ levels in M(IL-4). NIC1 overexpression in THP-1-derived macrophages increased PPARγ protein stability by delaying its proteasome-mediated degradation, but did not affect its mRNA. Phosphorylation of AKT was enhanced in NIC1-overexpressing cells, and a specific AKT inhibitor reduced the level of PPARγ. NIC1-overexpressing THP-1 cells exhibited increased CD36 levels via activation of PPARγ, resulting in enhanced intracellular lipid accumulation. In summary, this study provides evidence linking Notch signaling and PPARγ via AKT in M(IL-4).


Subject(s)
Macrophage Activation , PPAR gamma/metabolism , Receptors, Notch/metabolism , Chromones/pharmacology , Culture Media/metabolism , Humans , Interleukin-4/metabolism , Jagged-1 Protein/antagonists & inhibitors , Jagged-1 Protein/metabolism , Lipid Metabolism/drug effects , Lipid Metabolism/immunology , Morpholines/pharmacology , Phosphorylation , Primary Cell Culture , Protein Stability , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Signal Transduction/immunology , THP-1 Cells
4.
Biochem Pharmacol ; 174: 113845, 2020 04.
Article in English | MEDLINE | ID: mdl-32032581

ABSTRACT

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor. Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype. TNBC expresses AHR and AHR ligands have anti-cancer activity in TNBC. The aggressiveness of TNBC is due in part to JAG1-NOTCH1 signaling. ITE is a putative endogenous AHR ligand. We show that ITE reduces the expression of JAG1 the amount of Notch 1 intracellular domain (NICD1) and the phosphorylation of STAT3 (at tyrosine 705) in TNBC MDA-MB-231 cells. The STAT3 inhibitor STATTIC also reduced JAG1. STAT3, thus, mediates regulation of JAG1 in MDA-MB-231 cells. Reducing the expression of JAG1 with short interfering RNA decreases the growth, migration and invasiveness of MDA-MB-231 cells. JAG1, therefore, has cellular effects in MDA-MB-231 cells under basal conditions. We consequently evaluated if exposing cells to greater amounts of JAG1 would counteract ITE cellular effects in MDA-MB-231 cells. The results show that JAG1 does not counteract the cellular effects of ITE. JAG1, thus, has no effect on growth or invasiveness in MDA-MB-231 cells treated with ITE. JAG1, therefore, has context dependent roles in MDA-MB-231 cells (basal versus ITE treatment). The results also show that other pathways, not inhibition of the JAG1-NOTCH1 pathway, are important for mediating the growth and invasive inhibitory effect of ITE on MDA-MB-231 cells.


Subject(s)
Antineoplastic Agents/metabolism , Basic Helix-Loop-Helix Transcription Factors/metabolism , Indoles/metabolism , Jagged-1 Protein/metabolism , Receptor, Notch1/metabolism , Receptors, Aryl Hydrocarbon/metabolism , Thiazoles/metabolism , Triple Negative Breast Neoplasms/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Dose-Response Relationship, Drug , Female , Humans , Indoles/pharmacology , Indoles/therapeutic use , Jagged-1 Protein/antagonists & inhibitors , Ligands , MCF-7 Cells , Receptor, Notch1/antagonists & inhibitors , Signal Transduction/drug effects , Signal Transduction/physiology , Thiazoles/pharmacology , Thiazoles/therapeutic use , Triple Negative Breast Neoplasms/drug therapy
5.
Autoimmunity ; 52(4): 176-184, 2019 06.
Article in English | MEDLINE | ID: mdl-31322442

ABSTRACT

Liver ischemia-reperfusion injury (IRI) represents a risk factor for early graft dysfunction and an obstacle to expanding donor pool in orthotopic liver transplantation (OLT). Kupffer cells (KCs) are the largest antigen-presenting cell (APC) group and the primary modulators of inflammation in liver tissues. The vital role of Notch1/Jagged1 pathway in mouse OLT model has been reported, however, its potential therapeutic mechanism is unknown. Here, we made use of short hairpin RNA-Jagged1 and AAV-Jagged1 to explore the effects of Notch1/Jagged1 pathway in OLT. In vitro, blockade of Notch1/Jagged1 pathway downregulated the expression of Hairy and enhancer of split-1 (Hes1) gene, which in turn increased the proinflammatory effects of KCs. Moreover, the anti-inflammatory effects of Notch1/Jagged1 pathway were induced by inhibiting Hes1/gene of phosphate and tension/protein kinase B/Toll-like receptor 4/nuclear factor kappa B (Hes1/PTEN/AKT/TLR4/NF-κB) axis in KCs. In vivo, we used a well-established mouse model of OLT to mimic clinical transplantation. Mice were stochastically divided into 6 groups: Sham group (n = 15); Normal saline (NS) group (n = 15); Adeno-associated virus-green fluorescent protein (AAV-GFP) group (n = 15); AAV-Jagged1 group (n = 15); Clodronate liposome (CL) group (n = 15); CL+AAV-Jagged1 group (n = 15) . After OLT the liver damage in AAV-Jagged1 group were significantly accentuated compared to the AAV-GFP group. While blockade of Jagged1 aftet clearence of KCs by CL would not lead to further liver injuries. Taken together, our study demonstrated that blockade of Notch1/Jagged1 pathway aggravates inflammation induced by lipopolysaccharide (LPS) via Hes1/PTEN/AKT/TLR4/NF-κB in KCs, and the blockade of Notch1/Jagged1 pathway in donor liver increased neutrophil/macrophage infiltration and hepatocellular apoptosis, which suggested the function of Notch1/Jagged1 pathway in mouse OLT and highlighted the protective function of Notch1/Jagged1 pathway in liver transplantation.


Subject(s)
Jagged-1 Protein/antagonists & inhibitors , Kupffer Cells/metabolism , Liver Transplantation/adverse effects , Receptor, Notch1/antagonists & inhibitors , Reperfusion Injury/pathology , Animals , Apoptosis/genetics , Cells, Cultured , Clodronic Acid/pharmacology , Inflammation/pathology , Jagged-1 Protein/genetics , Liver/cytology , Liver/metabolism , Male , Mice , Mice, Inbred BALB C , NF-kappa B/biosynthesis , PTEN Phosphohydrolase/biosynthesis , Proto-Oncogene Proteins c-akt/biosynthesis , RNA Interference , RNA, Small Interfering/genetics , Receptor, Notch1/genetics , Toll-Like Receptor 4/biosynthesis , Transcription Factor HES-1/biosynthesis
7.
Endocrinology ; 159(1): 184-198, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29126263

ABSTRACT

The Notch pathway is a highly conserved juxtacrine signaling mechanism that is important for many cellular processes during development, including differentiation and proliferation. Although Notch is important during ovarian follicle formation and early development, its functions during the gonadotropin-dependent stages of follicle development are largely unexplored. We observed positive regulation of Notch activity and expression of Notch ligands and receptors following activation of the luteinizing hormone-receptor in prepubertal mouse ovary. JAG1, the most abundantly expressed Notch ligand in mouse ovary, revealed a striking shift in localization from oocytes to somatic cells following hormone stimulation. Using primary cultures of granulosa cells, we investigated the functions of Jag1 using small interfering RNA knockdown. The loss of JAG1 led to suppression of granulosa cell differentiation as marked by reduced expression of enzymes and factors involved in steroid biosynthesis, and in steroid secretion. Jag1 knockdown also resulted in enhanced cell proliferation. These phenotypes were replicated, although less robustly, following knockdown of the obligate canonical Notch transcription factor RBPJ. Intracellular signaling analysis revealed increased activation of the mitogenic phosphatidylinositol 3-kinase/protein kinase B and mitogen-activated protein kinase/extracellular signal-regulated kinase pathways following Notch knockdown, with a mitogen-activated protein kinase kinase inhibitor blocking the enhanced proliferation observed in Jag1 knockdown granulosa cells. Activation of YB-1, a known regulator of granulosa cell differentiation genes, was suppressed by Jag1 knockdown. Overall, this study reveals a role of Notch signaling in promoting the differentiation of preovulatory granulosa cells, adding to the diverse functions of Notch in the mammalian ovary.


Subject(s)
Gene Expression Regulation, Developmental , Granulosa Cells/metabolism , Immunoglobulin J Recombination Signal Sequence-Binding Protein/metabolism , Jagged-1 Protein/metabolism , MAP Kinase Signaling System , Receptor, Notch2/agonists , Receptor, Notch3/agonists , Animals , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Chorionic Gonadotropin/pharmacology , Estradiol/metabolism , Female , Gene Expression Regulation, Developmental/drug effects , Genes, Reporter/drug effects , Gonadotropins, Equine/pharmacology , Granulosa Cells/cytology , Granulosa Cells/drug effects , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Immunoglobulin J Recombination Signal Sequence-Binding Protein/antagonists & inhibitors , Immunoglobulin J Recombination Signal Sequence-Binding Protein/genetics , Jagged-1 Protein/antagonists & inhibitors , Jagged-1 Protein/genetics , MAP Kinase Signaling System/drug effects , Mice, Inbred Strains , Mice, Transgenic , Progesterone/metabolism , RNA Interference , Receptor, Notch2/genetics , Receptor, Notch2/metabolism , Receptor, Notch3/genetics , Receptor, Notch3/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism
8.
Oncol Rep ; 39(3): 1063-1071, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29286145

ABSTRACT

This study investigated the roles of Notch­1 in colorectal carcinoma, to assess the mechanisms. The expression of Notch­1 and its ligand-Jagged1 was detected in human colorectal carcinoma, colorectal adenoma, paracancerous tissue and normal colorectal tissue by immunohistochemistry. Colorectal carcinoma cell lines were utilized to confirm the expression of Notch­1 in colorectal carcinoma cells. Lentiviral- encoding Notch­1­siRNA, as well as Notch­1 inhibitor was employed to silence Notch­1 expression and to inhibit Notch­1 activity in HT29 cells, respectively. As evidenced, Notch­1 and Jagged1 were highly expressed in colorectal carcinoma and colorectal adenoma tissues, compared with those in paracancerous tissue and normal colorectal tissue. However, the expression of Notch­1 and Jagged1 was comparable in colorectal carcinoma and colorectal adenoma tissues, and in paracancerous and normal colorectal tissues. After screening colorectal carcinoma cell lines, Notch­1 was extensively expressed in COLO 205, HT29, SW480 and SW1116 cells, but slightly expressed in LoVo cells. Subsequently, HT29 cell line was selected to investigate the roles of Notch­1 in tumor cell growth and apoptosis. Lenti-viral encoding Notch­1 siRNA significantly decreased Notch­1 expression, inhibited cell growth, arrested the cell cycle at G1 phase and promoted apoptosis. These effects were further confirmed by the Notch­1 inhibitor DAPT. Additionally, we evidenced that Notch­1 silence promoted P21 and PUMA expression in HT29 cells. Taken together, Notch­1 is an oncogene in colorectal carcinoma and the inhibition of Notch­1 could delay the cell growth and promote apoptosis in colorectal cancer.


Subject(s)
Biomarkers, Tumor/metabolism , Colorectal Neoplasms/pathology , Diamines/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Jagged-1 Protein/antagonists & inhibitors , Receptor, Notch1/antagonists & inhibitors , Thiazoles/pharmacology , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Proliferation/drug effects , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/enzymology , Humans , Jagged-1 Protein/metabolism , Prognosis , Receptor, Notch1/metabolism , Signal Transduction , Tumor Cells, Cultured
9.
Cancer Cell ; 32(6): 731-747.e6, 2017 Dec 11.
Article in English | MEDLINE | ID: mdl-29232552

ABSTRACT

Bone metastasis is a major health threat to breast cancer patients. Tumor-derived Jagged1 represents a central node in mediating tumor-stromal interactions that promote osteolytic bone metastasis. Here, we report the development of a highly effective fully human monoclonal antibody against Jagged1 (clone 15D11). In addition to its inhibitory effect on bone metastasis of Jagged1-expressing tumor cells, 15D11 dramatically sensitizes bone metastasis to chemotherapy, which induces Jagged1 expression in osteoblasts to provide a survival niche for cancer cells. We further confirm the bone metastasis-promoting function of osteoblast-derived Jagged1 using osteoblast-specific Jagged1 transgenic mouse model. These findings establish 15D11 as a potential therapeutic agent for the prevention or treatment of bone metastasis.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antineoplastic Agents/pharmacology , Bone Neoplasms/drug therapy , Bone Neoplasms/secondary , Jagged-1 Protein/antagonists & inhibitors , Animals , Humans , Mice , Mice, Transgenic , Osteoblasts/drug effects , Xenograft Model Antitumor Assays
10.
Cancer Res ; 77(20): 5628-5638, 2017 10 15.
Article in English | MEDLINE | ID: mdl-28904063

ABSTRACT

Myeloid-derived suppressor cells (MDSC) are a major obstacle to promising forms of cancer immunotherapy, but tools to broadly limit their immunoregulatory effects remain lacking. In this study, we assessed the therapeutic effect of the humanized anti-Jagged1/2-blocking antibody CTX014 on MDSC-mediated T-cell suppression in tumor-bearing mice. CTX014 decreased tumor growth, affected the accumulation and tolerogenic activity of MDSCs in tumors, and inhibited the expression of immunosuppressive factors arginase I and iNOS. Consequently, anti-Jagged therapy overcame tumor-induced T-cell tolerance, increased the infiltration of reactive CD8+ T cells into tumors, and enhanced the efficacy of T-cell-based immunotherapy. Depletion of MDSC-like cells restored tumor growth in mice treated with anti-Jagged, whereas coinjection of MDSC-like cells from anti-Jagged-treated mice with cancer cells delayed tumor growth. Jagged1/2 was induced in MDSCs by tumor-derived factors via NFkB-p65 signaling, and conditional deletion of NFkB-p65 blocked MDSC function. Collectively, our results offer a preclinical proof of concept for the use of anti-Jagged1/2 to reprogram MDSC-mediated T-cell suppression in tumors, with implications to broadly improve the efficacy of cancer therapy. Cancer Res; 77(20); 5628-38. ©2017 AACR.


Subject(s)
Immunotherapy/methods , Jagged-1 Protein/antagonists & inhibitors , Jagged-1 Protein/immunology , Myeloid-Derived Suppressor Cells/immunology , Neoplasms, Experimental/immunology , Neoplasms, Experimental/therapy , Animals , Antibodies/immunology , Antibodies/pharmacology , Carcinoma, Lewis Lung/immunology , Carcinoma, Lewis Lung/therapy , Female , Humans , Immunotherapy, Adoptive/methods , Melanoma, Experimental/immunology , Melanoma, Experimental/therapy , Mice , Mice, Inbred C57BL , Signal Transduction , T-Lymphocytes/immunology
11.
Stem Cells ; 35(7): 1747-1759, 2017 07.
Article in English | MEDLINE | ID: mdl-28376567

ABSTRACT

Insufficient vessel growth associated with ischemia remains an unresolved issue in vascular medicine. Mesenchymal stem cells (MSCs) have been shown to promote angiogenesis via a mechanism that is potentiated by hypoxia. Overexpression of hypoxia inducible factor (HIF)-1α in MSCs improves their therapeutic potential by inducing angiogenesis in transplanted tissues. Here, we studied the contribution of exosomes released by HIF-1α-overexpressing donor MSCs (HIF-MSC) to angiogenesis by endothelial cells. Exosome secretion was enhanced in HIF-MSC. Omics analysis of miRNAs and proteins incorporated into exosomes pointed to the Notch pathway as a candidate mediator of exosome communication. Interestingly, we found that Jagged1 was the sole Notch ligand packaged into MSC exosomes and was more abundant in HIF-MSC than in MSC controls. The addition of Jagged1-containing exosomes from MSC and HIF-MSC cultures to endothelial cells triggered transcriptional changes in Notch target genes and induced angiogenesis in an in vitro model of capillary-like tube formation, and both processes were stimulated by HIF-1α. Finally, subcutaneous injection of Jagged 1-containing exosomes from MSC and HIF-MSC cultures in the Matrigel plug assay induced angiogenesis in vivo, which was more robust when they were derived from HIF-MSC cultures. All Jagged1-mediated effects could be blocked by prior incubation of exosomes with an anti-Jagged 1 antibody. All together, the results indicate that exosomes derived from MSCs stably overexpressing HIF-1α have an increased angiogenic capacity in part via an increase in the packaging of Jagged1, which could have potential applications for the treatment of ischemia-related disease. Stem Cells 2017;35:1747-1759.


Subject(s)
Exosomes/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Jagged-1 Protein/genetics , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/metabolism , Neovascularization, Physiologic , Animals , Antibodies, Neutralizing/pharmacology , Cell Hypoxia , Coculture Techniques , Dental Pulp/cytology , Dental Pulp/metabolism , Exosomes/chemistry , Gene Expression Regulation , Genes, Reporter , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Jagged-1 Protein/antagonists & inhibitors , Jagged-1 Protein/metabolism , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Mesenchymal Stem Cells/cytology , Mice , Mice, Nude , Primary Cell Culture , Tetraspanin 30/genetics , Tetraspanin 30/metabolism , Transduction, Genetic , Transplantation, Heterologous , Red Fluorescent Protein
12.
Exp Cell Res ; 352(1): 104-112, 2017 03 01.
Article in English | MEDLINE | ID: mdl-28161537

ABSTRACT

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.


Subject(s)
Cell Movement , Colorectal Neoplasms/prevention & control , Epithelial-Mesenchymal Transition , Jagged-1 Protein/antagonists & inhibitors , Receptor, Notch2/antagonists & inhibitors , Animals , Apoptosis , Blotting, Western , Cell Proliferation , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Fluorescent Antibody Technique , Gene Expression Regulation, Neoplastic , Humans , Jagged-1 Protein/genetics , Jagged-1 Protein/metabolism , Mice , Mice, Inbred BALB C , Mice, Nude , MicroRNAs , Neoplasm Metastasis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Receptor, Notch2/genetics , Receptor, Notch2/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
13.
Biochem Biophys Res Commun ; 484(4): 833-838, 2017 03 18.
Article in English | MEDLINE | ID: mdl-28161636

ABSTRACT

Breast cancer affects one in eight women throughout the course of their lifetime creating a demand for novel prevention strategies against this disease. The Notch signaling pathway is often aberrantly activated in human malignancies including breast cancer. Alpha secretases, including ADAM (A Disintegrin and Metalloprotease) -10 and -17, are proteases that play a key role in the cleavage of cell surface molecules and subsequent ligand-mediated activation of Notch signaling pathway. High expression levels of ADAM10 and 17 have been clinically associated with a lower disease-free survival in breast cancer patients. This study was undertaken to determine the effect of diallyl trisulfide (DATS), a bioactive organosulfide found in garlic and other Allium vegetables, on alpha secretases in breast cancer cells. Here we report for the first time that DATS inhibits the expression of ADAM10 and ADAM17 in estrogen-independent MDA-MB-231 and estrogen-dependent MCF-7 breast cancer cells, and in Harvey-ras (H-Ras) transformed MCF10A-H-Ras breast epithelial cells. We also show that DATS induces a dose-dependent reduction in colony formation ability of MDA-MB-231 and MCF-7 cells, suggesting a long-term effect of DATS on growth inhibition of breast cancer cells. Furthermore, we show that DATS inhibits the Notch ligands Jagged-1 and Jagged-2 involved in activation of Notch signaling pathway. Collectively, these findings show that DATS targets Notch pathway components overexpressed in breast cancer tumors and may serve as a functionally relevant bioactive for breast cancer prevention.


Subject(s)
Allium/chemistry , Allyl Compounds/administration & dosage , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Anticarcinogenic Agents/administration & dosage , Breast Neoplasms/enzymology , Breast Neoplasms/prevention & control , Disulfides/administration & dosage , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Humans , Jagged-1 Protein/antagonists & inhibitors , Jagged-2 Protein/antagonists & inhibitors , MCF-7 Cells , Vegetables
14.
Stem Cell Res ; 17(2): 391-400, 2016 09.
Article in English | MEDLINE | ID: mdl-27643563

ABSTRACT

During development, endothelial cells (EC) display tissue-specific attributes that are unique to each vascular bed, as well as generic signaling mechanisms that are broadly applied to create a patent circulatory system. We have previously utilized human embryonic stem cells (hESC) to generate tissue-specific EC sub-types (Rafii et al., 2013) and identify pathways that govern growth and trans-differentiation potential of hESC-derived ECs (James et al., 2010). Here, we elucidate a novel Notch-dependent mechanism that induces endothelial to mesenchymal transition (EndMT) in confluent monolayer cultures of hESC-derived ECs. We demonstrate density-dependent induction of EndMT that can be rescued by the Notch signaling inhibitor DAPT and identify a positive feedback signaling mechanism in hESC-ECs whereby trans-activation of Notch by DLL4 ligand induces elevated expression and surface presentation of DLL4. Increased Notch activation in confluent hESC-EC monolayer cultures induces areas of EndMT containing transitional cells that are marked by increased Jagged1 expression and reduced Notch signal integration. Jagged1 loss of function in monolayer hESC-ECs induces accelerated feedback stimulation of Notch signaling, increased expression of cell-autonomous, cis-inhibitory DLL4, and EndMT. These data elucidate a novel interplay of Notch ligands in modulating pathway activation during both expansion and EndMT of hESC-derived ECs.


Subject(s)
Endothelial Cells/metabolism , Human Embryonic Stem Cells/cytology , Receptors, Notch/metabolism , Benzamides/pharmacology , Cell Transdifferentiation , Cells, Cultured , Diamines/pharmacology , Dioxoles/pharmacology , Endothelial Cells/cytology , Human Embryonic Stem Cells/metabolism , Humans , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Intracellular Signaling Peptides and Proteins/chemistry , Intracellular Signaling Peptides and Proteins/metabolism , Jagged-1 Protein/antagonists & inhibitors , Jagged-1 Protein/genetics , Jagged-1 Protein/metabolism , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/chemistry , Membrane Proteins/metabolism , Microscopy, Fluorescence , RNA Interference , RNA, Small Interfering/metabolism , Receptors, Notch/antagonists & inhibitors , Receptors, Notch/genetics , Signal Transduction/drug effects , Thiazoles/pharmacology , Transcriptional Activation
15.
Biosci Rep ; 36(4)2016 08.
Article in English | MEDLINE | ID: mdl-27129289

ABSTRACT

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.


Subject(s)
Diabetes Mellitus, Experimental/genetics , Epidermis/metabolism , Jagged-1 Protein/genetics , Receptor, Notch1/genetics , Stem Cells/metabolism , Wound Healing/genetics , Animals , Cell Movement , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Epidermis/injuries , Epithelial Cells/cytology , Epithelial Cells/metabolism , Female , Gene Expression Regulation , Genetic Vectors/chemistry , Genetic Vectors/metabolism , Jagged-1 Protein/antagonists & inhibitors , Jagged-1 Protein/metabolism , Lentivirus/genetics , Lentivirus/metabolism , Mice , Mice, Inbred C57BL , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Receptor, Notch1/metabolism , Signal Transduction , Stem Cells/cytology , Streptozocin , Transcription Factor HES-1/genetics , Transcription Factor HES-1/metabolism
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