Jag1/2 maintain esophageal homeostasis and suppress foregut tumorigenesis by restricting the basal progenitor cell pool.

Basal progenitor cells are crucial for maintaining foregut (the esophagus and forestomach) homeostasis. When their function is dysregulated, it can promote inflammation and tumorigenesis. However, the mechanisms underlying these processes remain largely unclear. Here, we employ genetic mouse models to reveal that Jag1/2 regulate esophageal homeostasis and foregut tumorigenesis by modulating the function of basal progenitor cells. Deletion of Jag1/2 in mice disrupts esophageal and forestomach epithelial homeostasis. Mechanistically, Jag1/2 deficiency impairs activation of Notch signaling, leading to reduced squamous epithelial differentiation and expansion of basal progenitor cells. Moreover, Jag1/2 deficiency exacerbates the deoxycholic acid (DCA)-induced squamous epithelial injury and accelerates the initiation of squamous cell carcinoma (SCC) in the forestomach. Importantly, expression levels of JAG1/2 are lower in the early stages of human esophageal squamous cell carcinoma (ESCC) carcinogenesis. Collectively, our study demonstrates that Jag1/2 are important for maintaining esophageal and forestomach homeostasis and the onset of foregut SCC.

Jagged2 targeting in lung cancer activates anti-tumor immunity via Notch-induced functional reprogramming of tumor-associated macrophages.

Signaling through Notch receptors intrinsically regulates tumor cell development and growth. Here, we studied the role of the Notch ligand Jagged2 on immune evasion in non-small cell lung cancer (NSCLC). Higher expression of JAG2 in NSCLC negatively correlated with survival. In NSCLC pre-clinical models, deletion of Jag2, but not Jag1, in cancer cells attenuated tumor growth and activated protective anti-tumor T cell responses. Jag2-/- lung tumors exhibited higher frequencies of macrophages that expressed immunostimulatory mediators and triggered T cell-dependent anti-tumor immunity. Mechanistically, Jag2 ablation promoted Nr4a-mediated induction of Notch ligands DLL1/4 on cancer cells. DLL1/4-initiated Notch1/2 signaling in macrophages induced the expression of transcription factor IRF4 and macrophage immunostimulatory functionality. IRF4 expression was required for the anti-tumor effects of Jag2 deletion in lung tumors. Antibody targeting of Jagged2 inhibited tumor growth and activated IRF4-driven macrophage-mediated anti-tumor immunity. Thus, Jagged2 orchestrates immunosuppressive systems in NSCLC that can be overcome to incite macrophage-mediated anti-tumor immunity.

miR-541 is associated with the prognosis of liver cirrhosis and directly targets JAG2 to inhibit the activation of hepatic stellate cells.

BACKGROUND: The activation of hepatic stellate cells (HSCs) has been emphasized as a leading event of the pathogenesis of liver cirrhosis, while the exact mechanism of its activation is largely unknown. Furthermore, the novel non-invasive predictors of prognosis in cirrhotic patients warrant more exploration. miR-541 has been identified as a tumor suppressor in hepatocellular carcinoma and a regulator of fibrotic disease, such as lung fibrosis and renal fibrosis. However, its role in liver cirrhosis has not been reported. METHODS: Real-time PCR was used to detect miR-541 expression in the liver tissues and sera of liver cirrhosis patients and in the human LX-2. Gain- and loss-of-function assays were performed to evaluate the effects of miR-541 on the activation of LX-2. Bioinformatics analysis and a luciferase reporter assay were conducted to investigate the target gene of miR-541. RESULTS: miR-541 was downregulated in the tissues and sera of patients with liver cirrhosis, which was exacerbated by deteriorating disease severity. Importantly, the lower expression of miR-541 was associated with more episodes of complications including ascites and hepatic encephalopathy, a shorter overall lifespan, and decompensation-free survival. Moreover, multivariate Cox's regression analysis verified lower serum miR-541 as an independent risk factor for liver-related death in cirrhotic patients (HR = 0.394; 95% CI: 0.164-0.947; P = 0.037). miR-541 was also decreased in LX-2 cells activated by TGF-ß and the overexpression of miR-541 inhibited the proliferation, activation and hydroxyproline secretion of LX-2 cells. JAG2 is an important ligand of Notch signaling and was identified as a direct target gene of miR-541. The expression of JAG2 was upregulated in the liver tissues of cirrhotic patients and was inversely correlated with miR-541 levels. A rescue assay further confirmed that JAG2 was involved in the function of miR-541 when regulating LX-2 activation and Notch signaling. CONCLUSIONS: Dysregulation of miR-541/JAG2 axis might be a as a new mechanism of liver fibrosis, and miR-541 could serve as a novel non-invasive biomarker and therapeutic targets for liver cirrhosis.

Assemblies of JAG1 and JAG2 determine tracheobronchial cell fate in mucosecretory lung disease.

Mucosecretory lung disease compromises airway epithelial function and is characterized by goblet cell hyperplasia and ciliated cell hypoplasia. Goblet and ciliated cell types are derived from tracheobronchial stem/progenitor cells via a Notch-dependent mechanism. Although specific arrays of Notch receptors regulate cell fate determination, the function of the ligands Jagged1 (JAG1) and JAG2 is unclear. This study examined JAG1 and JAG2 function using human air-liquid-interface cultures that were treated with γ-secretase complex (GSC) inhibitors, neutralizing peptides/antibodies, or WNT/ß-catenin pathway antagonists/agonists. These experiments revealed that JAG1 and JAG2 regulated cell fate determination in the tracheobronchial epithelium; however, their roles did not adhere to simple necessity and sufficiency rules. Biochemical studies indicated that JAG1 and JAG2 underwent posttranslational modifications that resulted in generation of a JAG1 C-terminal peptide and regulated the abundance of full-length JAG2 on the cell surface. GSC and glycogen synthase kinase 3 were implicated in these posttranslational events, but WNT agonist/antagonist studies and RNA-Seq indicated a WNT-independent mechanism. Collectively, these data suggest that posttranslational modifications create distinct assemblies of JAG1 and JAG2, which regulate Notch signal strength and determine the fate of tracheobronchial stem/progenitor cells.

miR-2392 functions as tumour suppressor and inhibits malignant progression of hepatocellular carcinoma via directly targeting JAG2.

BACKGROUND & AIMS: Dysregulation of microRNA (miRNA) expression in various cancers and their vital roles in malignant progression of cancers are well investigated. Our previous studies have analysed miRNAs that promote malignant progression in hepatocellular carcinoma (HCC); this study aims to systematically elucidate the mechanism of metastasis suppressor miRNAs in HCC. METHODS: High-throughput RNA sequencing was used to identify anti-metastatic miRNAs. The relative expression levels of miRNAs were confirmed by qRT-PCR. The biological functions of miRNAs were detected in vitro and in vivo. Circulating tumour cells (CTCs) were enriched from blood samples of HCC patients and cultured by three-dimensional (3D) system. Kaplan-Meier and Cox regression were used to analyse the value of potential target mRNAs on overall survival. RESULTS: miR-2392 was significantly down-regulated in HCC. Overexpression of miR-2392 suppressed proliferation, clonogenicity, mobility, spheroid formation and maintenance of cancer stem cells (CSC)-like characteristics in HCC cells. CTCs from HCC patients with lower serum miR-2392 level had stronger cell spheroid formation ability. A negative correlation between the content of miR-2392 in serum and the number of CTC spheroids had been found. We identified Jagged2 (JAG2) as a direct target of miR-2392. miR-2392 inhibited the expression of JAG2 by targeting 3'-UTR of JAG2. Down-regulation of JAG2 inhibited the overexpression effects of miR-2392 in vitro and in vivo. JAG2 is highly expressed in HCC and is closely related to poor prognosis and survival of patients. CONCLUSIONS: miR-2392 may play a role as a tumour suppressor to guide the individualized precise treatment of HCC.

Relationship of Notch Signal, Surfactant Protein A, and Indomethacin in Cervix During Preterm Birth: Mast Cell and Jagged-2 May Be Key in Understanding Infection-mediated Preterm Birth.

Although it is thought that there is a close relationship between Notch signal and preterm birth, the functioning of this mechanism in the cervix is unknown. The efficacy of surfactants and prostaglandin inhibitors in preterm labor is also still unclear. In this study, 48 female CD-1 mice were distributed to pregnant control (PC), Sham, PBS, indomethacin (2 mg/kg; intraperitoneally), lipopolysaccharides (LPS) (25 µg/100 µl; intrauterine), LPS + IND, and Surfactant Protein A Block (SP-A Block: SP-A B; the anti-SP-A antibody was applied 20 µg/100µl; intrauterine) groups. Tissues were examined by immunohistochemistry, immunofluorescence, and Western blot analysis. LPS administration increased the expression of N1 Dll-1 and Jagged-2 (Jag-2). Although Toll-like receptor (Tlr)-2 significantly increased in the LPS-treated and SP-A-blocked groups, Tlr-4 significantly increased only in the LPS-exposed groups. It was observed that Jag-2 is specifically expressed by mast cells. Overall, this experimental model shows that some protein responses increase throughout the uterus, starting at a specific point on the cervix epithelium. Surfactant Protein A, which we observed to be significantly reduced by LPS, may be associated with the regulation of the epithelial response, especially during preterm delivery due to infection. On the contrary, prostaglandin inhibitors can be considered an option to delay infection-related preterm labor with their dose-dependent effects. Finally, the link between mast cells and Jag-2 could potentially be a control switch for preterm birth.

A form of muscular dystrophy associated with pathogenic variants in JAG2.

JAG2 encodes the Notch ligand Jagged2. The conserved Notch signaling pathway contributes to the development and homeostasis of multiple tissues, including skeletal muscle. We studied an international cohort of 23 individuals with genetically unsolved muscular dystrophy from 13 unrelated families. Whole-exome sequencing identified rare homozygous or compound heterozygous JAG2 variants in all 13 families. The identified bi-allelic variants include 10 missense variants that disrupt highly conserved amino acids, a nonsense variant, two frameshift variants, an in-frame deletion, and a microdeletion encompassing JAG2. Onset of muscle weakness occurred from infancy to young adulthood. Serum creatine kinase (CK) levels were normal or mildly elevated. Muscle histology was primarily dystrophic. MRI of the lower extremities revealed a distinct, slightly asymmetric pattern of muscle involvement with cores of preserved and affected muscles in quadriceps and tibialis anterior, in some cases resembling patterns seen in POGLUT1-associated muscular dystrophy. Transcriptome analysis of muscle tissue from two participants suggested misregulation of genes involved in myogenesis, including PAX7. In complementary studies, Jag2 downregulation in murine myoblasts led to downregulation of multiple components of the Notch pathway, including Megf10. Investigations in Drosophila suggested an interaction between Serrate and Drpr, the fly orthologs of JAG1/JAG2 and MEGF10, respectively. In silico analysis predicted that many Jagged2 missense variants are associated with structural changes and protein misfolding. In summary, we describe a muscular dystrophy associated with pathogenic variants in JAG2 and evidence suggests a disease mechanism related to Notch pathway dysfunction.

Cholera toxin induces food allergy through Th2 cell differentiation which is unaffected by Jagged2.

AIMS: Cholera toxin is often used to induce food allergies. However, its exact mode of action and effect remain ambiguous. In this study, we established a BALB/c mouse cholera toxin/ovalbumin-induced food allergy model to determine the molecular basis and signaling mechanisms of the immune regulation of cholera toxin during food allergy. MATERIALS AND METHODS: The adjuvant activity of cholera toxin was analyzed by establishing mouse allergy model, and the allergic reaction of each group of mice was evaluated. The effect of cholera toxin on Th1/Th2 cell differentiation was analyzed to further explore the role of cholera toxin in allergen immune response. We stimulated bone marrow-derived dendritic cells (BMDCs) with cholera toxin in vitro to investigate the effect of cholera toxin on Notch ligand expression. BMDCs and naive CD4+T cells were co-cultured in vitro, and their cytokine levels were examined to investigate whether cholera toxin regulates Th cell differentiation via the Jagged2 Notch signaling pathway. KEY FINDINGS: The results showed that in the presence of allergens, cholera toxin promotes Th2 cell differentiation and enhances the body's immune response. Cholera toxin induces expression of the Notch ligand Jagged2, but Jagged2 Notch signaling pathway is not required to promote BMDCs-mediated differentiation of Th2 cells. SIGNIFICANCE: This study initially revealed the mechanism by which cholera toxin plays an adjuvant role in food allergy, and provides reference for future related research.

Tumour-associated neutrophils orchestrate intratumoural IL-8-driven immune evasion through Jagged2 activation in ovarian cancer.

BACKGROUND: Tumour associated neutrophils (TANs) play a controversial role in regulating immune surveillance and immune evasion in various malignancies. Here, we investigated the relevance of TANs with the prognosis and immune microenvironment of epithelial ovarian cancer (EOC). METHODS: We characterised TANs using flow cytometric analysis and immunofluorescence analysis. The prognostic merit of TANs in EOC was evaluated using cox regression analysis. Furthermore, we explored the therapeutic merit of targeting Notch signalling in EOC and determined its involvement in the immune microenvironment. RESULTS: High level of TANs is associated with a dismal prognosis and immune tolerance in EOC. TANs impaired cytotoxic effects of CD8+ T cells partly through Jagged2 (JAG2). Notch pathway blocked using γ-secretase inhibitor LY3039478 and anti-JAG2 antibody led to retarded tumour growth and augmented cytotoxic effects of CD8+ T cells. IL-8 contributes to the recruitment of TANs and the induction of JAG2 expression in TANs. Blockade of CXCR2 signalling reduces tumour growth rate, accompanied by a decreasing amount of TANs and increasing activity of CD8+ T cells. JAG2+TANs is an independent predictor of clinical outcomes. CONCLUSION: JAG2+TANs are closely linked to IL-8-driven immune evasion microenvironment and may serve as a promising therapeutic target for the reinvigoration of anti-tumour immunity.

Valproic acid overcomes sorafenib resistance by reducing the migration of Jagged2-mediated Notch1 signaling pathway in hepatocellular carcinoma cells.

Sorafenib resistance is a classic problem related to the treatment of advanced hepatocellular carcinoma (HCC). There is a recognized need to explore new drug resistance mechanisms and develop novel strategies to overcome the acquired resistance to sorafenib. Although one study has showed that the anti-epileptic drug valproic acid (VPA) could sensitize transforming growth factor-ß (TGF-ß)-induced sorafenib-resistant HCC cells, it is unclear whether VPA could reverse resistance to long-term clinical treatment with sorafenib. In this study, we successfully established sorafenib-resistant HCC cells by long-term sorafenib exposure. Compared with sensitive HCC cells, the proliferation, anti-apoptotic capability and migration of the sorafenib-resistant cells were enhanced. In addition, we found that VPA combined with sorafenib could overcome drug resistance by downregulating Jagged2-mediated Notch1 signaling pathway and epithelial-mesenchymal transition (EMT)-related proteins. Furthermore, the combination of VPA and sorafenib could obviously increase the sensitivity of drug-resistant cells in vitro and synergistically suppress tumor growth in vivo. These results provided a new insight that the use of VPA in combination with sorafenib was an effective method for clinically solving the problem of sorafenib resistance by modulating the Jagged2-mediated Notch1 signaling pathway and reversing the EMT phenotype.

Jagged2 progressively increased expression from Stage I to III of Bladder Cancer and Melatonin-mediated downregulation of Notch/Jagged2 suppresses the Bladder Tumorigenesis via inhibiting PI3K/AKT/mTOR/MMPs signaling.

Background: This study assessed the expression of Jagged2 in human bladder cancer (BC) tested the hypothesis that melatonin (Mel) inhibited the tumorigenesis of BC cells mainly through downregulating the Notch/Jagged2 and PI3K/AKT/mTOR/MMPs(2&9) signaling pathways. Methods and Results: Tissue array from BC patients showed that the gene and protein expressions of JAG2/Jagged2 were significantly upregulated from T1 to T3 (primary tumor size) and from stage I to III (all p<0.001). In vitro study showed that in BC cell line of UMUC3, the cellular and protein expressions of Jagged2 were significantly attenuated in Mel-treated UMUC3 and further attenuated in UMUC3 shRNA silenced Notch/JAG2 (UMUC3KD) than in UMUC3 only (all p<0.0001). The protein expressions of Notch/Jagged2/MMPs(2&9)/PI3K/p-AKT/mTOR/p53/ratio of LC3BII/LC3B-I were significantly progressively reduced from UMUC3 to UMUC3+Mel/1.0mM, further to UMUC3+Mel/2.0mM and furthermore to UMUC3KD (all p<0.0001). The cell proliferation/invasion/colony formation/healing-process were significantly inhibited in Mel-treated/2.0mM UMUC3 and further significantly inhibited in UMUC3KD regardless of Mel treatment as compared with UMUC3 only (all p<0.0001). By day 28 after UMUC3 implanted into nude mouse back, the BC weight/volume were significantly reduced in UMUC3+Mel (100 mg/kg/day) and furthermore reduced in UMUC3KD (all p<0.0001) as compared with UMUC3 only (all p<0.0001). The cellular (MMPs(2&9)/Notch/Jagged2) and protein (Notch/Jagged2/PI3K/p-AKT/mTOR/MMPs(2&9)) exhibited a similar trend, whereas the PTEN protein level exhibited an opposite pattern of PI3K among three groups (all p<0.0001). Conclusion: Notch/Jagged-PI3K/p-AKT/mTOR/MMPs is one essential signaling pathway for BC survival, proliferation and invasion that were remarkably suppressed by Mel treatment.

Overexpression of JAG2 is related to poor outcomes in oral squamous cell carcinoma.

OBJECTIVES: JAG2 is one of Notch ligands, which recently appear to exert various carcinogenesis. In the present study, we aimed to unveil the relation of JAG2 expression and clinicopathological features in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: We examined JAG2 expression in OSCC plus adjacent nontumorous epithelia in eight patients. Ninety-one OSCC tissue specimens were immunohistochemically stained with specific antibodies to JAG2. The immunoreactivities of JAG2 were correlated with clinicopathological factors, including the prognosis of patients. Chi-square test, Kaplan-Meier survival, and Cox proportional hazard analysis were used to determine the statistical value of JAG2 expression in OSCC. RESULTS: JAG2 mRNA expression was much expressed in OSCC tissues compared with adjacent tissue specimens in five of eight patients. JAG2 immunoreactivity was found at invasion front in 31 of 91 OSCC. JAG2 immunoreactivity was significantly associated with age, less than 50 years old of patients (P = .048). Kaplan-Meier analysis demonstrated that the patients with JAG2 immunoreactvty have a short overall survival. With the Cox proportional hazard regression mode, the independent factors predictive of poor overall survival included JAG2 immunoreactivity (P < .05). CONCLUSIONS: The present findings suggest that JAG2 overexpression, especially at the cancer invasion front, has potential prognostic value.

Haematopoietic stem cells in perisinusoidal niches are protected from ageing.

With ageing, intrinsic haematopoietic stem cell (HSC) activity decreases, resulting in impaired tissue homeostasis, reduced engraftment following transplantation and increased susceptibility to diseases. However, whether ageing also affects the HSC niche, and thereby impairs its capacity to support HSC function, is still widely debated. Here, by using in-vivo long-term label-retention assays we demonstrate that aged label-retaining HSCs, which are, in old mice, the most quiescent HSC subpopulation with the highest regenerative capacity and cellular polarity, reside predominantly in perisinusoidal niches. Furthermore, we demonstrate that sinusoidal niches are uniquely preserved in shape, morphology and number on ageing. Finally, we show that myeloablative chemotherapy can selectively disrupt aged sinusoidal niches in the long term, which is linked to the lack of recovery of endothelial Jag2 at sinusoids. Overall, our data characterize the functional alterations of the aged HSC niche and unveil that perisinusoidal niches are uniquely preserved and thereby protect HSCs from ageing.

JAG2/Notch2 inhibits intervertebral disc degeneration by modulating cell proliferation, apoptosis, and extracellular matrix.

BACKGROUND: Intervertebral disc degeneration (IVDD)-related disorders are the major causes of low back pain. A previous study suggested that Notch activation serves as a protective mechanism and is a part of the compensatory response that maintains the necessary resident nucleus pulposus (NP) cell proliferation to replace lost or non-functional cells. However, the exact mechanism remains to be determined. In this study, we aimed to investigate the role of JAG2/Notch2 in NP cell proliferation and apoptosis. METHODS: Recombinant JAG2 or Notch2, Hes1, and Hey2 siRNAs were used to activate or inhibit Notch signaling. Cell proliferation, apoptosis, cell cycle regulatory factors, and pathways associated with Notch-mediated proliferation were examined. In vivo experiments involving an intradiscal injection of Sprague-Dawley rats were performed. RESULTS: Recombinant JAG2 induced Notch2 and Hes1/Hey2 expression together with NP cell proliferation. Downregulation of Notch2/Hes1/Hey2 induced G0/G1 phase cell cycle arrest in NP cells. Moreover, Notch2 mediated NP cell proliferation by regulating cyclin D1 and by activating PI3K/Akt and Wnt/ß-catenin signaling. Furthermore, Notch signaling inhibited TNF-α-promoted NP cell apoptosis by suppressing the formation of the RIP1-FADD-caspase-8 complex. Finally, we found that intradiscal injection of JAG2 alleviated IVDD and that sh-Notch2 aggravated IVDD in a rat model. These results indicated that JAG2/Notch2 inhibited IVDD by modulating cell proliferation, apoptosis, and extracellular matrix. The JAG2/Notch2 axis regulated NP cell proliferation via PI3K/Akt and Wnt/ß-catenin signaling and inhibited TNF-α-induced apoptosis by suppressing the formation of the RIP1-FADD-caspase-8 complex. CONCLUSIONS: The current and previous results shed light on the therapeutic implications of targeting the JAG2/Notch2 axis to inhibit or reverse IVDD.

Delta-like 1-mediated cis-inhibition of Jagged1/2 signalling inhibits differentiation of human epidermal cells in culture.

Epidermal homeostasis depends on a balance between self-renewal of stem cells and terminal differentiation of their progeny. Notch signalling is known to play a role in epidermal  stem cell patterning and differentiation. However, the molecular mechanisms are incompletely understood. Here we demonstrate dynamic patterns of Notch ligand and receptor expression in cultured human epidermis. Notch2 and 3 act together to promote differentiation, while Notch1 decreases stem cell proliferation. The Notch ligand Jagged1 triggers differentiation when presented on an adhesive substrate or on polystyrene beads and over-rides the differentiation inhibitory effect of cell spreading. In contrast, Delta-like 1 (Dll1) overexpression abrogates the pro-differentiation effect of Jagged1 in a cell autonomous fashion. We conclude that Dll1 expression by stem cells not only stimulates differentiation of neighbouring cells in trans, but also inhibits differentiation cell autonomously. These results highlight the distinct roles of different Notch receptors and ligands in controlling epidermal homeostasis.

Crosstalk between BMP and Notch Induces Sox2 in Cerebral Endothelial Cells.

Bone morphogenetic protein (BMP) and Notch signaling are critical for endothelial cell (EC) differentiation in vascular development. Recent studies have shown that excess BMP activity induces Notch signaling in cerebral ECs resulting in arteriovenous malformation (AVMs). However, it is unclear how the crosstalk between BMP and Notch signaling affects cerebral EC differentiation at the gene regulatory level. Here, we report that BMP6 activates the activin receptor-like kinase (ALK) 3, a BMP type 1 receptor, to induce Notch1 receptor and Jagged1 and Jagged2 ligands. We show that increased expression of the Notch components alters the transcriptional regulatory complex in the SRY-Box 2 (Sox2) promoter region so as to induce its expression in cerebral ECs. Together, our results identify Sox2 as a direct target of BMP and Notch signaling and provide information on how altered BMP and Notch signaling affects the endothelial transcriptional landscape.

Determinant roles of dendritic cell-expressed Notch Delta-like and Jagged ligands on anti-tumor T cell immunity.

BACKGROUND: Notch intercellular communication instructs tissue-specific T-cell development and function. In this study, we explored the roles of dendritic cell (DC)-expressed Notch ligands in the regulation of T-cell effector function. METHODS: We generated mice with CD11c lineage-specific deletion of Notch Delta-like ligand (Dll)1 and Jagged (Jag)2. Using these genetically-ablated mice and engineered pharmacological Notch ligand constructs, the roles of various Delta-like and Jagged ligands in the regulation of T-cell-mediated immunity were investigated. We assessed tumor growth, mouse survival, cytokine production, immunophenotyping of myeloid and lymphoid populations infiltrating the tumors, expression of checkpoint molecules and T-cell function in the experimental settings of murine lung and pancreatic tumors and cardiac allograft rejection. Correlative studies were also performed for the expression of NOTCH ligands, NOTCH receptors and PD-1 on various subsets of myeloid and lymphoid cells in tumor-infiltrating immune cells analyzed from primary human lung cancers. RESULTS: Mice with CD11c lineage-specific deletion of Notch ligand gene Dll1, but not Jag2, exhibited accelerated growth of lung and pancreatic tumors concomitant with decreased antigen-specific CD8+T-cell functions and effector-memory (Tem) differentiation. Increased IL-4 but decreased IFN-γ production and elevated populations of T-regulatory and myeloid-derived suppressor cells were observed in Dll1-ablated mice. Multivalent clustered DLL1-triggered Notch signaling overcame DC Dll1 deficiency and improved anti-tumor T-cell responses, whereas the pharmacological interference by monomeric soluble DLL1 construct suppressed the rejection of mouse tumors and cardiac allograft. Moreover, monomeric soluble JAG1 treatment reduced T-regulatory cells and improved anti-tumor immune responses by decreasing the expression of PD-1 on CD8+Tem cells. A significant correlation was observed between DC-expressed Jagged and Delta-like ligands with Tem-expressed PD-1 and Notch receptors, respectively, in human lung tumor-infiltrates. CONCLUSION: Our data show the importance of specific expression of Notch ligands on DCs in the regulation of T-cell effector function. Thus, strategies incorporating selectively engineered Notch ligands could provide a novel approach of therapeutics for modulating immunity in various immunosuppressive conditions including cancer.

Long noncoding RNA ENST00000455974 plays an oncogenic role through up-regulating JAG2 in human DNA mismatch repair-proficient colon cancer.

DNA mismatch repair-proficient colon cancer is the most common type of colon cancer, but its initiation and progression are still unknown. Our previous study has revealed that a long noncoding RNA (lncRNA) ENST00000455974 was significantly associated with TNM stage and distant metastasis in patients with DNA mismatch repair-proficient (pMMR) colon cancer (CC). Here, firstly, we observed that ENST00000455974 was gradual increased across colon normal-adenoma-carcinoma-metastasis sequence by quantitative real-time PCR. Secondly, ENST00000455974 showed a better sensitivity and specificity than CEA and CA19-9 in the diagnosis of pMMR CC by drawing the receiver operating characteristic (ROC) curve. Thirdly, a higher level of ENST00000455974 was associated with a poorer patient survival. Furthermore, Knockdown of ENST00000455974 led to reduced proliferation and migration of colon cancer cells. Mechanistically, ENST00000455974 was mainly located in the nucleus of colon cancer cells and it promoted the growth and metastasis of pMMR CC cells through up-regulating JAG2.

JAG2 signaling induces differentiation of CD14+ monocytes into Langerhans cell histiocytosis-like cells.

Langerhans cell histiocytosis (LCH) is a MAPK pathway-driven disease characterized by the accumulation of CD1a+ langerin+ cells of unknown origin. We have previously reported that the Notch signaling pathway is active in LCH lesions and that the Notch ligand Jagged2 (JAG2) induces CD1a and langerin expression in monocytes in vitro. Here we show that Notch signaling induces monocytes to acquire an LCH gene signature and that Notch inhibition suppresses the LCH phenotype. In contrast, while also CD1c+ dendritic cells or IL-4-stimulated CD14+ monocytes acquire CD1a and langerin positivity in culture, their gene expression profiles and surface phenotypes are more different from primary LCH cells. We propose a model where CD14+ monocytes serve as LCH cell precursor and JAG2-mediated activation of the Notch signaling pathway initiates a differentiation of monocytes toward LCH cells in selected niches and thereby contributes to LCH pathogenesis.

Misoprostol-Induced Modification of the Notch Signaling Pathway in the Human Cervix.

The complex and multifactorial mechanisms that initiate and sustain the early labor process in the human uterus and cervix are still not well defined. Cervical maturation or ripening is likely to play a key role in preparing for birth. Prostaglandins have many different functions, including the regulation of uterine contractility and structure during pregnancy. The prostaglandin E1 analogue misoprostol is frequently used as a uterotonic and cervical ripening agent. Notch is a transmembrane receptor family responsible for basic functions such as cell survival, cell-cell communication, and differentiation and decidualization in pregnancy. However, our understanding of the effect of Notch signaling on the cervical ripening process is limited. This study was conducted in 20 pregnant women aged at 12 to 20 weeks of gestation undergoing medical abortion for fetal or maternal indications. True-Cut needle biopsies were taken from the anterior cervix 4 hours after oral ingestion of 200-µg misoprostol or before the ingestion of misoprostol in the control group. Cervical expression of Notch receptors and ligands changed during the early phase of prostaglandin-induced preterm labor. Four hours after the administration of misoprostol, it was seen that N1 expression increased in muscle, while DLL1 and J2 expression increased in blood vessels, and N4 expression increased in macrophages. Knowing the mechanisms that initiate preterm birth is the most important step in planning the treatments and actions to prevent premature birth. As a signal that affects and perhaps directs preterm labor, Notch is prone to be an important actor in this process.