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.

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.

Association between the JAG2 gene polymorphism and the occurrence of nonsyndromic cleft lip with or without cleft palate in northwest Chinese population / 中华医学遗传学杂志

OBJECTIVE@#To assess the association of JAG2 gene single nucleotide polymorphisms with the occurrence of nonsyndromic cleft lip with or without cleft palate (NSCLP) among northwest Chinese population.@*METHODS@#A case-control study was carried out on 301 NSCLP patients and 304 healthy controls. An iMLDR(TM) genotyping technique was used to detect three single nucleotide polymorphisms (SNPs) [rs741859 (T/C), rs11621316 (A/G) and rs1057744(C/T)] of the JAG2 gene. Allelic and genotypic frequencies and haplotypic distribution among the two groups were compared.@*RESULTS@#A significant difference was found in the frequency of C and T alleles for rs741859 between the two groups. The CT genotype of rs741859 could significantly reduce the risk for NSCLP to 65% (P 0.8), whose distribution difference between the two groups was not statistically significant (P> 0.05).@*CONCLUSION@#The CT genotype of the JAG2 gene rs741859 may confer a protective effect for NSCLP among northwest Chinese population.

Effect of triptolide on expressions of Notch receptors and ligands in rats with adjuvant- induced arthritis and reduced pulmonary function / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of triptolide on Notch receptor and ligand expressions in rats with adjuvant-induced arthritis (AA).</p><p><b>METHODS</b>Forty rats were randomly divided into normal control (NC) group, model (MC) group, methotrexate group and triptolide groups. Rat models of AA were established by an intradermal injection of 0.1 mL Freund's complete adjuvant into the right paw. Twelve days after the injection, the rats were treated with corresponding drugs for 30 days; the rats in NC group and MC group were given saline only. Paw edema volume (E), arthritis index (AI), pulmonary function, histomorphologies, and Notch receptor/ ligand expression in the lung tissue were analyzed after the treatments.</p><p><b>RESULTS</b>Compared with the NC group, E, AI, Notch3, Notch4, and Delta1 expressions in the lung tissues significantly increased while pulmonary function and pulmonary expressions of Notch1, Jagged1, and Jagged2 significantly decreased the model rats (P<0.01). Compared with the MC group, triptolide-treated rats showed significantly improved pulmonary functions, increased expressions of Notch1, Jagged1, and Jagged2 and decreased expressions of Notch3, Notch4, and Delta1 in the lungs (P<0.05, P<0.01); the therapeutic effect of triptolide was better than that of methotrexate.</p><p><b>CONCLUSION</b>Triptolide can reduce inflammatory reaction and immune complex deposition to improve joint and pulmonary symptoms in rats with AA possibly by up-regulating the expressions of Notch3, Notch4, and Delta1 and down-regulating the expressions of Jagged1, Jagged2, and Notch1.</p>

Inhibitory effect of pumpkin protein on expression of Notch signal in RPMI8226 myeloma cells / 中国实验血液学杂志

This study was aimed to explore the inhibitory effect of pumpkin protein (cucurmosin, CUS) on proliferation of RPMI8226 myeloma cells in vitro and its mechanism. Western blot was used to detect the expression level of Notch-1, Jagged-2, P-Akt and NF-KB in the myeloma cells treated by different concentrations of CUS. The results demonstrated that CUS could down-regulate the protein expression levels of Notch1, Jagged-2, P-Akt and NF-KB in the myeloma cells and with time-and concentration-dependent way, at the same time CUS could also decrease the expressions of BCL-2 and P-Akt. It is concluded that CUS can obviously inhibit the RPMI8226 cell proliferation in vitro, down-regulate the expression levels of Notch signal and its down-stream target genes. Therefore, Notch signaling pathway can be used as a new treatment target for multiple myeloma, and CUS may be become a potential new drug for regulating Notch signaling pathway.

Expression and significance of Notch-1 and Jagged-2 in patients with Hirschsprung disease / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the expression of Notch-1 and Jagged-2 in the normal and spastic segments of colon in patients with Hirschsprung disease(HD), and to explore the correlation of Notch-1 and Jagged-2 with pathogenesis of HD.</p><p><b>METHODS</b>From 2005 to 2010, resected colon specimens of 30 cases with HD were selected for this study. Normal colonic segments were served as control group, while the transitional and spastic segments as experimental group. Immunohistochemical staining, Western blotting, and RT-PCR were applied to detect the expression of Notch-1 and Jagged-2.</p><p><b>RESULTS</b>A large number of Notch-1 and Jagged-2 positive gangliocytes were observed in the control group, while none was observed in spastic segments. Significantly less Notch-1 and Jagged-2 positive gangliocytes were found in the transitional segments. Western blotting revealed that Notch-1 and Jagged-2 protein levels in spastic segments (0.19±0.02 and 0.13±0.04) were less than that in transitional segments and normal segments (0.58±0.05 and 0.52±0.04, 0.72±0.04 and 0.69±0.04, respectively)(P<0.05). RT-PCR revealed that Notch-1 and Jagged-2 mRNA levels were consistent with protein expression.</p><p><b>CONCLUSION</b>Notch-1 and Jagged-2 are not expressed in spastic colon segments, which may be associated with the pathogenesis of HD.</p>

Inhibitory effect of phenylhexyl isothiocyanate on notch signaling of multiple myeloma cells in vitro / 中国实验血液学杂志

In order to investigate the mechanisms of phenylhexyl isothiocyanate (PHI) inhibiting the proliferation of multiple myeloma cell RPMI8226 in vitro, the RPMI8226 cells were co-cultured with PHI of various concentrations. The inhibition of proliferation was measured by MTT test and the cell apoptosis was assayed by DAPI staining. The changes of Notch1, Jagged2, BCL-2 and p-Akt proteins in the PHI-treated cells were detected by Western blot. The results showed that PHI inhibited RPMI8226 cell proliferation in certain concentration range and induced their apoptosis. The inhibiting effect caused by PHI showed a concentration-and time-dependent manner. The PHI decreased expressions of Notch1 and Jagged2 proteins in a concentration-and time-dependent manners, the levels of BCL-2 and p-Akt declined at the same time. It is concluded that PHI can inhibit proliferation of RPMI8226 cells, and induce their apoptosis. The cell apoptosis is associated with the inhibition of Notch signaling and downstream targets BCL-2 and p-Akt proteins of RPMI8226 cells, PHI may be a new Notch signaling inhibitor and a promising therapeutic drug for multiple myeloma.

Function of Delta4 gene and its effects on 32D cell differentiation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Notch activation leads to transcriptional suppression of lineage-specific genes, inhibiting differentiation in response to inductive signals. The Notch signal system contains three parts: Notch molecules, Notch ligands and effectors. Delta4 is a newly-discovered Notch ligand which has received the attention of few detailed studies. This study sought to explore the biological function of Delta4 and observe its effects on 32D cell differentiation.</p><p><b>METHODS</b>Delta4-expressing vector pTracer.CMV.Delta4.FLAG was constructed using molecular biological techniques. CHO cells stably transfected with pTracer.CMV.Delta4.FLAG were confirmed to have a Delta4 protein band via Western blotting. High-expression Delta4-CHO clones were selected for the following functional studies. Notch1-CHO and Notch2-CHO were used as host cells. After transiently transfecting with transition protein 1 (TP1), Delta4 activity was compared in both cell lines by means of luciferase analysis. CHO cells were incubated with Notch1-32D cells that had been transfected with Notch1 and were observed for granulocyte colony-stimulating factor (G-CSF)-induced differentiation. Jagged2-CHO and Delta4-CHO cells transfected with the Notch ligands Jagged2 and Delta4, respectively, were incubated with Notch1-32D cells to observed inhibition of Notch on G-CSF-induced differentiation.</p><p><b>RESULTS</b>The vector pTracer.CMV.Delta4.FLAG was constructed successfully. CHO cells were stably transfected with the vector pTracer.CMV.Delta4.FLAG. Two CHO cell lines expressing Delta4 at high levels were selected for use in the study. Delta4 was found to induce signal activity via both Notch1 and Notch2 and the induction of signaling activity was stronger in Notch2 cells than in Notch1 cells. Compared with other Notch ligands, Delta4 was slightly weaker than Jagged2, but stronger than Delta1 and Jagged1 in terms of Notch1 ligands. In terms of Notch2, Delta4 had a strong signaling activity, but was weaker than Delta1, Jagged1, and Jagged2. Jagged2 could inhibit Notch1-32D cell differentiation induced by G-CSF, but Delta4 could not.</p><p><b>CONCLUSIONS</b>Delta4 induces both Notch1 and Notch2 activity and is a ligand for both of them. The effect of Delta4 is stronger on Notch2 than that on Notch1. Jagged2 can inhibit Notch1-32D cell differentiation induced by G-CSF, but Delta4 cannot.</p>