JAK-STAT Research Articles

A dicoumarol-graphene oxide quantum dot polymer inhibits porcine reproductive and respiratory syndrome virus through the JAK-STAT signaling pathway.

Porcine reproductive and respiratory syndrome virus (PRRSV) causes substantial economic losses in the global swine industry. The current vaccine options offer limited protection against PRRSV transmission, and there are no effective commercial antivirals available. Therefore, there is an urgent need to develop new antiviral strategies that slow global PRRSV transmission. In this study, we synthesized a dicoumarol-graphene oxide quantum dot (DIC-GQD) polymer with excellent biocompatibility. This polymer was synthesized via an electrostatic adsorption method using the natural drug DIC and GQDs as raw materials. Our findings demonstrated that DIC exhibits high anti-PRRSV activity by inhibiting the PRRSV replication stage. The transcriptome sequencing analysis revealed that DIC treatment stimulates genes associated with the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signalling pathway. In porcine alveolar macrophages (PAMs), DIC-GQDs induce TYK2, JAK1, STAT1, and STAT2 phosphorylation, leading to the upregulation of JAK1, STAT1, STAT2, interferon-β (IFN-β) and interferon-stimulated genes (ISGs). Animal challenge experiments further confirmed that DIC-GQDs effectively alleviated clinical symptoms and pathological reactions in the lungs, spleen, and lymph nodes of PRRSV-infected pigs. These findings suggest that DIC-GQDs significantly inhibits PRRSV proliferation by activating the JAK/STAT signalling pathway. Therefore, DIC-GQDs hold promise as an alternative treatment for PRRSV infection.

Unveiling divergent treatment prognoses in IDHwt-GBM subtypes through multiomics clustering: a swift dual MRI-mRNA model for precise subtype prediction

BackgroundIDH1-wildtype glioblastoma multiforme (IDHwt-GBM) is a highly heterogeneous and aggressive brain tumour characterised by a dismal prognosis and significant challenges in accurately predicting patient outcomes. To address these issues and personalise treatment approaches, we aimed to develop and validate robust multiomics molecular subtypes of IDHwt-GBM. Through this, we sought to uncover the distinct molecular signatures underlying these subtypes, paving the way for improved diagnosis and targeted therapy for this challenging disease.MethodsTo identify stable molecular subtypes among 184 IDHwt-GBM patients from TCGA, we used the consensus clustering method to consolidate the results from ten advanced multiomics clustering approaches based on mRNA, lncRNA, and mutation data. We developed subtype prediction models using the PAM and machine learning algorithms based on mRNA and MRI data for enhanced clinical utility. These models were validated in five independent datasets, and an online interactive system was created. We conducted a comprehensive assessment of the clinical impact, drug treatment response, and molecular associations of the IDHwt-GBM subtypes.ResultsIn the TCGA cohort, two molecular subtypes, class 1 and class 2, were identified through multiomics clustering of IDHwt-GBM patients. There was a significant difference in survival between Class 1 and Class 2 patients, with a hazard ratio (HR) of 1.68 [1.15–2.47]. This difference was validated in other datasets (CGGA: HR = 1.75[1.04, 2.94]; CPTAC: HR = 1.79[1.09–2.91]; GALSS: HR = 1.66[1.09–2.54]; UCSF: HR = 1.33[1.00–1.77]; UPENN HR = 1.29[1.04–1.58]). Additionally, class 2 was more sensitive to treatment with radiotherapy combined with temozolomide, and this sensitivity was validated in the GLASS cohort. Correspondingly, class 2 and class 1 exhibited significant differences in mutation patterns, enriched pathways, programmed cell death (PCD), and the tumour immune microenvironment. Class 2 had more mutation signatures associated with defective DNA mismatch repair (P = 0.0021). Enriched pathways of differentially expressed genes in class 1 and class 2 (P-adjust < 0.05) were mainly related to ferroptosis, the PD-1 checkpoint pathway, the JAK-STAT signalling pathway, and other programmed cell death and immune-related pathways. The different cell death modes and immune microenvironments were validated across multiple datasets. Finally, our developed survival prediction model, which integrates molecular subtypes, age, and sex, demonstrated clinical benefits based on the decision curve in the test set. We deployed the molecular subtyping prediction model and survival prediction model online, allowing interactive use and facilitating user convenience.ConclusionsMolecular subtypes were identified and verified through multiomics clustering in IDHwt-GBM patients. These subtypes are linked to specific mutation patterns, the immune microenvironment, prognoses, and treatment responses.

Macrophages exploit the mannose receptor and JAK-STAT1-MHC-II pathway to drive antigen presentation and the antimycobacterial immune response after BCG vaccination.

Tuberculosis (TB), caused by Mycobacterium tuberculosis ( M. tb), remains one of the leading causes of fatal infectious diseases worldwide. The only licensed vaccine, Mycobacterium bovis Bacillus Calmette-Guérin (BCG), has variable efficacy against TB in adults. Insufficiency of immune cell function diminishes the protective effects of the BCG vaccine. It is critical to clarify the mechanism underlying the antimycobacterial immune response during BCG vaccination. Macrophage mannose receptor (MR) is important for enhancing the uptake and processing of glycoconjugated antigens from pathogens for presentation to T cells, but the roles of macrophage MR in the BCG-induced immune response against M. tb are not yet clear. Here, we discover that macrophage MR deficiency impairs the antimycobacterial immune response in BCG-vaccinated mice. Mechanistically, macrophage MR triggers JAK-STAT1 signaling, which promotes antigen presentation via upregulated MHC-II and induces IL-12 production by macrophages, contributing to CD4 + T cell activation and IFN-γ production. MR deficiency in macrophages reduces the vaccine efficacy of BCG and increases susceptibility to M. tb H37Ra challenge in mice. Our results suggest that MR is critical for macrophage antigen presentation and the antimycobacterial immune response to BCG vaccination and offer valuable guidance for the preventive strategy of BCG immunization.

PDE1B, a potential biomarker associated with tumor microenvironment and clinical prognostic significance in osteosarcoma

PDE1B had been found to be involved in various diseases, including tumors and non-tumors. However, little was known about the definite role of PDE1B in osteosarcoma. Therefore, we mined public data on osteosarcoma to reveal the prognostic values and immunological roles of the PDE1B gene. Three osteosarcoma-related datasets from online websites were utilized for further data analysis. R 4.3.2 software was utilized to conduct difference analysis, prognostic analysis, gene set enrichment analysis (GSEA), nomogram construction, and immunological evaluations, respectively. Experimental verification of the PDE1B gene in osteosarcoma was conducted by qRT-PCR and western blot, based on the manufacturer's instructions. The PDE1B gene was discovered to be lowly expressed in osteosarcoma, and its low expression was associated with poor OS (all P < 0.05). Experimental verifications by qRT-PCR and western blot results remained consistent (all P < 0.05). Univariate and multivariate Cox regression analyses indicated that the PDE1B gene had independent abilities in predicting OS in the TARGET osteosarcoma dataset (both P < 0.05). GSEA revealed that PDE1B was markedly linked to the calcium, cell cycle, chemokine, JAK STAT, and VEGF pathways. Moreover, PDE1B was found to be markedly associated with immunity (all P < 0.05), and the TIDE algorithm further shed light on that patients with high-PDE1B expression would have a better immune response to immunotherapies than those with low-PDE1B expression, suggesting that the PDE1B gene could prevent immune escape from osteosarcoma. The PDE1B gene was found to be a tumor suppressor gene in osteosarcoma, and its high expression was related to a better OS prognosis, suppressing immune escape from osteosarcoma.

Activation of NOTCH signaling impedes cell proliferation and survival in acute megakaryoblastic leukemia

The genetic lesions that drive acute megakaryoblastic leukemia (AMKL) have not been fully elucidated. To search for genetic alterations in AMKL, we performed targeted deep sequencing in 34 AMKL patient samples and 8 AMKL cell lines and detected frequent genetic mutations in the NOTCH pathway in addition to previously reported alterations in GATA-1 and the JAK-STAT pathway. Pharmacological and genetic NOTCH activation, but not inhibition, significantly suppressed AMKL cell proliferation in both in vitro and in vivo assays employing a patient-derived xenograft model. These results suggest that NOTCH inactivation underlies AMKL leukemogenesis. and NOTCH activation holds the potential for therapeutic application in AMKL.

Regulation of STAT1 Signaling in Human Pancreatic β-Cells by the Lysine Deacetylase HDAC6: A New Therapeutic Opportunity in Type 1 Diabetes?

Type 1 diabetes arises from the selective destruction of pancreatic β-cells by autoimmune mechanisms and intracellular pathways driven by Janus (JAK)-kinase mediated STAT isoforms (especially STAT1 & STAT2) are implicated as mediators of β-cell demise. Despite this, the molecular mechanisms that regulate JAK-STAT signalling in β-cells during the autoimmune attack remain only partially disclosed and the factors acting to antagonise pro-inflammatory STAT1 signalling are uncertain. We have recently implicated Signal Regulatory Protein (SIRP)-α in promoting β-cell viability in the face of ongoing islet autoimmunity and now reveal that this protein controls the availability of a cytosolic lysine deacetylase, HDAC6, whose activity regulates the phosphorylation and activation of STAT1. We provide evidence that STAT1 serves as a substrate for HDAC6 in β-cells and that sequestration of HDAC6 by SIRPα in response to anti-inflammatory cytokines (such as interleukin-13) leads to increased STAT1 acetylation. This then impairs the ability of STAT1 to promote gene transcription in response to pro-inflammatory cytokines including interferon-gamma (IFNγ). We further find that SIRPα is lost from the β-cells of subjects with recent-onset type 1 diabetes under conditions when HDAC6 is retained and STAT1 levels are increased. On this basis, we report a previously unrecognised role for cytokine-induced regulation of STAT1 acetylation in the control of β- cell viability and propose that targeted inhibition of HDAC6 activity may represent a novel therapeutic modality to promote β-cell viability in the face of active islet autoimmunity.

Construction of a ceRNA network and screening of potential biomarkers and molecular targets in male smokers with chronic obstructive pulmonary disease.

Circular RNAs (circRNAs) play an important role in the occurrence and development of diseases. However, the role of circRNAs in male smokers with chronic obstructive pulmonary disease (COPD) remains unclear. Stable COPD patients and healthy controls were recruited. Peripheral blood mononuclear cells (PBMCs) were extracted. After high-throughput RNA sequencing (RNA-Seq) of PBMCs, a bioinformatics method was used to analyse differentially expressed (DE) circRNAs (DEcircRNAs) and mRNAs (DEmRNAs). Total of 114 DEcircRNAs and 58 DEmRNAs were identified. Functional enrichment analysis showed that processes related to COPD include the regulation of interleukin (IL)-18, IL-5 and the NLRP3 inflammasome; differentiation of T helper type 1 (Th1), Th2, and Th17 cells, and the AMPK, Wnt, JAK-STAT, and PI3K-Akt signalling pathways. In the protein-protein interaction (PPI) network, the core genes were MYO16, MYL4, SCN4A, NRCAM, HMCN1, MYOM2, and IQSEC3. Small-molecule prediction results revealed potential drugs for the COPD treatment. Additionally, the circRNA-miRNA-mRNA competitive endogenous RNA (ceRNA) regulatory network was constructed. This study identified a set of dysregulated circRNAs and mRNAs and revealed potentially important genes, pathways, new small-molecule drugs and ceRNA regulatory networks in male smokers with COPD. These circRNAs might be prospective biomarkers or potential molecular targets of the ceRNA mechanism for COPD.

The Association between the JAK-STAT Pathway and Hypertension among Kenyan Women Diagnosed with Breast Cancer.

Breast cancer is the most common malignant tumor in women worldwide, and disproportionately affects Sub-Saharan Africa compared to high income countries. The global disease burden is growing, with Sub-Saharan Africa reporting majority of the cases. In Kenya, breast cancer is the most commonly diagnosed cancer, with an annual incidence of 7,243 new cases in 2022, representing 25.5% of all reported cancers in women. Evidence suggests that women receiving breast cancer treatment are at a greater risk of developing hypertension than women without breast cancer. Hypertension prevalence has been on the rise in SSA, with poor detection, treatment and control. The JAK-STAT signaling is activated in hormone receptor-positive breast tumors, leading to inflammation, cell proliferation, and treatment resistance in cancer cells. We sought to understand the association between the expression of JAK-STAT Pathway genes and hypertension among Kenyan women diagnosed with breast cancer. Breast tumor and non-tumor tissues were acquired from patients with a pathologic diagnosis of invasive breast carcinoma. RNA was extracted from fresh frozen tumor and adjacent normal tissue samples of 23 participants who had at least 50% tumor after pathological examination, as well as their corresponding adjacent normal samples. Differentially expressed JAK-STAT genes between tumor and normal breast tissues were assessed using the DESEq2 R package. Pearson correlation was used to assess the correlation between differentially expressed JAK-STAT genes and participants' blood pressure, heart rate, and body mass index (BMI). 11,868 genes were differentially expressed between breast tumor and non-tumor tissues. Eight JAK-STAT genes were significantly dysregulated (Log2FC ≥ 1.0 and an Padj ≤ 0.05), with two genes (CISH and SCNN1A) being upregulated. Six genes (TGFBR2, STAT5A, STAT5B, TGFRB3, SMAD9, and SOCS2) were downregulated. We identified STAT5A and SOCS2 genes to be significantly correlated with elevated systolic pressure and heart rate, respectively. Our study provides insights underlying the molecular mechanisms of hypertension among Kenyan women diagnosed with breast cancer. Understanding these mechanisms may help develop targeted treatments that may improve health outcomes of Kenyan women diagnosed with breast cancer. Longitudinal studies with larger cohorts will be needed to validate our results.

Aberrant expression of B7-H4 and B7-H5 contributes to the development of cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (CSCC) is the second most common malignant tumor of the skin. B7 homolog 4 (B7-H4) and B7-H5 (B7 homolog 5) are associated with a variety of tumors. Investigate the potential role of B7-H4 and B7-H5 in regulating the tumorigenesis and progression of CSCC. B7-H4 and B7-H5 transcriptome data were collected from GEO and TCGA databases and subjected to bioinformatical analysis by protein–protein interaction (PPI) network, functional enrichment analysis, immune analysis, and drug–gene interaction prediction analysis. We characterized the expression of B7-H4 and B7-H5 in carcinoma tissues of CSCC patients by immunohistochemistry. Meanwhile, the clinical correlation of B7-H4 and B7-H5 in CSCC was explored by statistical analysis. B7-H4 and B7-H5 genes were under-expressed in CSCC and correlated with tumor staging. According to GO and KEGG Pathway enrichment analysis, B7-H4, and B7-H5 can regulate the proliferation and activation of T cells, lymphocytes, and monocytes, and the expression of cytokines, such as IL-6 and IL-10, in CSCC. B7-H4 and B7-H5 are also jointly involved in the occurrence and development of CSCC via the JAK-STAT and Notch signaling pathways. We found that B7-H4 and B7-H5 proteins were abnormally highly expressed in CSCC tissue and correlated with tumor size and stage. Our findings offer new insights into the pathogenesis of CSCC and suggest that B7-H4 and B7-H5 are novel tissue biomarkers and promising therapeutic targets for CSCC.

A novel H‑tert immortalized human sebaceous gland cell line (XL-i-20) for the investigation of photodynamic therapy

BackgroundAcne vulgaris is a species-specific human disease. To date, there has been no established human sebocyte cell line of Asian origin. Our previous study has demonstrated the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of acne vulgaris, primarily attributed to its cytotoxic properties; however, its regulatory mechanism remains largely unknown. ObjectivesTo establish an immortalized human sebocyte cell line derived from Chinese population and investigate the underlying mechanism of ALA-PDT. MethodsHuman primary sebocytes were transfected with the human tert gene (h‑tert). The biological characteristics, including cell proliferation, cell markers, and sebum secretion function, were compared between primary sebocytes and the immortalized sebocytes (XL-i-20). Stimulations such as ALA-PDT, were applied respectively to both primary sebocytes and XL-i-20 cells to assess changes in their cellular functions. The transcriptome differences between primary sebocytes and XL-i-20 sebocytes were investigated using RNA-seq analysis. The XL-i-20 cell line was used to establish a sebaceous gland (SG) organoid culture, serving as a representative model of SG for the investigation of ALA-PDT. ResultsThe h‑tert immortalized sebocyte cell line exhibited the ability to be consecutively cultured for more than fifty passages. Both primary and immortalized cells expressed sebocyte markers such as epithelial membrane antigens (EMA, or MUC-1), Cytokeratin 7 (CK7) and adipose differentiation-related protein associated antigens (ADRP), and maintained sebum secretion function. The proliferative capacity of XL-i-20 was found to be significantly higher than that of primary sebocytes. The responses of XL-i-20 to ALA-PDT were indistinguishable from those elicited by primary sebocytes. Cell viability and sebum secretion were decreased after ALA-PDT in both two cell lines, and lipid-related proteins (SREBP-1/PPARγ) were down-regulated. The transcriptome data consistently demonstrated upregulation of genes related to inflammatory responses and downregulation of genes involved in lipid metabolism in both cell types following PDT. The analysis of common differential genes of primary sebocytes and XL-i-20 sebocytes post ALA-PDT showed that TNF signaling pathways, MAPK signaling pathways and JAK-STAT signaling pathways were activated. The SG organoids were spherical, which expressed markers of FANS and PLET1. Ki-67 was down-regulated after ALA-PDT. ConclusionsWe have developed an h‑tert immortalized sebocyte cell line from an Asian population. The cell line, XL-i-20, maintains the essential characteristics of its parent primary sebocytes. Moreover, XL-i-20 sebocyte exhibited a significant respond to ALA-PDT, demonstrating comparable phenotypic and molecular changes to primary sebocytes. Therefore, XL-i-20 and its derived SG organoid serve as appropriate in vitro models for investigating the efficacy and mechanisms of ALA-PDT in SG-related diseases.

Ciliary neurotrophic factor promotes the development of homocysteine-induced vascular endothelial injury through inflammation mediated by the JAK2/STAT3 signaling pathway

Elevated homocysteine (Hcy) levels have been recognized as significant risk factor for cardiovascular and cerebrovascular diseases, closely related to endothelial injury. While expression of Ciliary Neurotrophic Factor (CNTF) significantly increases during Hcy-induced vascular endothelial cell injury, the precise molecular pathways through which CNTF operates remain to be clarified. To induce vascular endothelial cell injury, human umbilical vein endothelial cells (HUVECs) were treated with Hcy. Cell viability and apoptosis in HUVECs were assessed using the CCK-8 assay and flow cytometry. Western blot analysis determined the expression levels of the JAK2-STAT3 pathway, inflammation-related factors (IL-1β, NLRP3, ICAM-1, VCAM-1), and apoptosis-related factors (cleaved Caspase-3 and Bax). Immunofluorescence staining and western blotting were employed to examine CD31 and α-SMA expression. Knockdown of CNTF was achieved using lentiviral interference, and its effects on inflammation and cell injury were evaluated. Chromatin immunoprecipitation (ChIP) and dual luciferase reporter analysis were conducted to investigate the interaction between the MAFK and CNTF promoters. Our results indicated that Hcy induced high expression of CNTF and activated the JAK2-STAT3 signaling pathway, thereby upregulating factors associated with inflammation and cell apoptosis. Inhibiting CNTF alleviated Hcy-induced inflammation and cell injury. MAFK was identified as a transcription factor promoting CNTF transcription, and its overexpression exacerbated inflammation and cell injury in Hcy-treated HUVECs through the CNTF-JAK2-STAT3 axis, which could be reversed by knocking down CNTF. Activation of MAFK leads to CNTF upregulation, which activates the JAK2-STAT3 signaling pathway, regulating inflammation and inducing injury in Hcy-exposed vascular endothelial cells. Targeting CNTF or its upstream regulator MAFK may represent potential therapeutic strategies for mitigating endothelial dysfunction associated with hyperhomocysteinemia and cardiovascular diseases.

Single-cell RNA sequencing identifies IFNICs as a cellular target for mitigating the progression of abdominal aortic aneurysm and rupture risk.

Abdominal aortic aneurysm (AAA) represents a life-threatening condition characterized by medial layer degeneration of the abdominal aorta. Nevertheless, knowledge regarding changes in regulators associated with aortic status remains incomplete. A thorough understanding of cell types and signaling pathways involved in the development and progression of AAAs is essential for the development of medical therapy. We harvested specimens of the abdominal aorta with different pathological features in Angiotensin II (AngII)-infused ApoE-/- mice, conducted scRNA-seq, identified a unique population of interferon-inducible monocytes/macrophages (IFNICs), which were amply found in the abdominal aortic aneurysms (AAAs). Gene set variation analysis (GSVA) revealed that activation of the cytosolic DNA sensing cGAS-STING and JAK-STAT pathways promoted the secretion of type I interferons in monocytes/macrophages and differentiated them into IFNICs. We generated myeloid cell-specific deletion of Sting1 (Lyz2-Cre+/-; Sting1flox/flox) mice and performed bone marrow transplantation and found that myeloid cell-specific deletion of Sting1 or Ifnar1 significantly reduced the incidence of AAA, aortic rupture rate and diameter of the abdominal aorta. Mechanistically, the activated pyroptosis- and inflammation-related signaling pathways, regulated by IRF7 in IFNICs, play critical roles in the developing AAAs. IFNICs is a unique monocyte/macrophage subset implicated in the development of AAAs and aortic rupture.

Perilipin1 inhibits Nosema bombycis proliferation by promoting Domeless- and Hop-mediated JAK-STAT pathway activation in Bombyx mori.

Lipid droplets (LDs) are dynamic organelles that participate in the regulation of lipid metabolism and cellular homeostasis inside of cells. LD-associated proteins, also known as perilipins (PLINs), are a family of proteins found on the surface of LDs that regulate lipid metabolism, immunity, and other functions. In silkworms, pébrine disease caused by infection by the microsporidian Nosema bombycis (Nb) is a severe threat to the sericultural industry. Although we found that Nb relies on lipids from silkworms to facilitate its proliferation, the relationship between PLINs and Nb proliferation remains unknown. Here, we found Nb infection caused the accumulation of LDs in the fat bodies of silkworm larvae. The characterized perilipin1 gene (plin1) promotes the accumulation of intracellular LDs and is involved in Nb proliferation. plin1 is similar to perilipin1 in humans and is conserved in all insects. The expression of plin1 was mostly enriched in the fat body rather than in other tissues. Knockdown of plin1 enhanced Nb proliferation, whereas overexpression of plin1 inhibited its proliferation. Furthermore, we confirmed that plin1 increased the expression of the Domeless and Hop in the JAK-STAT immune pathway and inhibited Nb proliferation. Taken together, our current findings demonstrate that plin1 inhibits Nb proliferation by promoting the JAK-STAT pathway through increased expression of Domeless and Hop. This study provides new insights into the complicated connections among microsporidia pathogens, LD surface proteins, and insect immunity.IMPORTANCELipid droplets (LDs) are lipid storage sites in cells and are present in almost all animals. Many studies have found that LDs may play a role in host resistance to pathogens and are closely related to innate immunity. The present study found that a surface protein of insect lipid droplets could not only regulate the morphological changes of lipid droplets but also inhibit the proliferation of a microsporidian pathogen Nosema bombycis (Nb) by activating the JAK-STAT signaling pathway. This is the first discovery of the relationship between microsporidian pathogen and insect lipid surface protein perilipin and insect immunity.

Syntaxin6 contributes to hepatocellular carcinoma tumorigenesis via enhancing STAT3 phosphorylation

BackgroundSyntaxin6 (STX6) is a SNARE (Soluble N-ethylmaleimide-sensitive factor attachment protein receptors) protein complex located in the trans-Golgi network and endosomes, which is closely associated with a variety of intracellular membrane transport events. STX6 has been shown to be overexpressed in a variety of human malignant tumors such as esophageal, colorectal, and renal cell carcinomas, and participates in tumorigenesis and development.MethodsBased on clinical public database and clinical liver samples analysis, the expression of STX6 in hepatocellular carcinoma (HCC) tissues was investigated. The effects of STX6 on proliferation, migration and invasion of HCC cell in vitro and in vivo were evaluated through gain- and loss-of-function studies. We further performed RNA-seq analysis and protein interactome analysis, to further decifer the detailed mechanisms of STX6 in the regulation of the JAK-STAT pathway in HCC.ResultsSTX6 expression was upregulated in HCC tissues and its expression was highly correlated with the high histological grade of the tumor. STX6 promoted HCC cell proliferation, migration and invasion both in vitro and in vivo. Mechanistically, STX6 mediated tumor progression depending on promoting the activation of JAK-STAT signaling pathway. Receptor for activated protein kinase C (RACK1) as an essential adaptor protein mediating STX6 regulation of JAK-STAT pathway. Specifically, STX6 interacted with RACK1 and then recruited signal transducer and activator of transcription 3 (STAT3) to form a protein-binding complex and activates STAT3 transcriptional activity.ConclusionsThis study provided a novel concept that STX6 exerted oncogenic effects by activating the STAT3 signaling pathway, and STX6 might be a promising therapeutic target for HCC.

Porcine deltacoronavirus nucleocapsid protein antagonizes JAK-STAT signaling pathway by targeting STAT1 through KPNA2 degradation.

Porcine deltacoronavirus (PDCoV) is an enteric pathogenic coronavirus that causes acute and severe watery diarrhea in piglets and has the ability of cross-species transmission, posing a great threat to swine production and public health. The interferon (IFN)-mediated signal transduction represents an important component of virus-host interactions and plays an essential role in regulating viral infection. Previous studies have suggested that multifunctional viral proteins encoded by coronaviruses antagonize the production of IFN via various means. However, the function of these viral proteins in regulating IFN-mediated signaling pathways is largely unknown. In this study, we demonstrated that PDCoV and its encoded nucleocapsid (N) protein antagonize type I IFN-mediated JAK-STAT signaling pathway. We identified that PDCoV infection stimulated but delayed the production of IFN-stimulated genes (ISGs). In addition, PDCoV inhibited JAK-STAT signal transduction by targeting the nuclear translocation of STAT1 and ISGF3 formation. Further evidence showed that PDCoV N is the essential protein involved in the inhibition of type I IFN signaling by targeting STAT1 nuclear translocation via its C-terminal domain. Mechanistically, PDCoV N targets STAT1 by interacting with it and subsequently inhibiting its nuclear translocation. Furthermore, PDCoV N inhibits STAT1 nuclear translocation by specifically targeting KPNA2 degradation through the lysosomal pathway, thereby inhibiting the activation of downstream sensors in the JAK-STAT signaling pathway. Taken together, our results reveal a novel mechanism by which PDCoV N interferes with the host antiviral response.IMPORTANCEPorcine deltacoronavirus (PDCoV) is a novel enteropathogenic coronavirus that receives increased attention and seriously threatens the pig industry and public health. Understanding the underlying mechanism of PDCoV evading the host defense during infection is essential for developing targeted drugs and effective vaccines against PDCoV. This study demonstrated that PDCoV and its encoded nucleocapsid (N) protein antagonize type I interferon signaling by targeting STAT1, which is a crucial signal sensor in the JAK-STAT signaling pathway. Further experiments suggested that PDCoV N-mediated inhibition of the STAT1 nuclear translocation involves the degradation of KPNA2, and the lysosome plays a role in KPNA2 degradation. This study provides new insights into the regulation of PDCoV N in the JAK-STAT signaling pathway and reveals a novel mechanism by which PDCoV evades the host antiviral response. The novel findings may guide us to discover new therapeutic targets and develop live attenuated vaccines for PDCoV infection.

Psoriatic arthritis - Tofacitinib as a new treatment

Introduction: JAK inhibitors are used in the treatment of psoriatic arthritis when there is a lack of effective response or intolerance to first-line drugs or their use must be discontinued due to the presence of side effects. JAK inhibitors inhibit the JAK-STAT signaling pathway which plays a significant role in the pathogenesis of many inflammatory and autoimmune diseases. This mechanism leads to a reduction in the level of pro-inflammatory cytokines which causes rapid improvement in the patient's clinical condition. Tofacitinib is the best-known drug in this group; its use carries an increased risk of cardiovascular events and reactivation of the varicella-zoster virus. Regular monitoring of patients results in faster detection of the first signs of undesirable effects and the cessation of their progression. The drug's safety profile is acceptable and the benefits outweigh possible complications. Aim of the study: The aim of the study is to summarize the available knowledge about tofacitinib treatment in psoriatic arthritis. The way of work, effectiveness of treatment and potential side effects were summarized and described. Materials and methods: The literature available in PubMed database was reviewed using the following keywords: “Psoriatic arthritis”, “Tofacitinib”, “JAK inhibitors”, “JAK-STAT” Conclusion: Tofacitinib treatment in rheumatology is used in psoriatic arthritis. The rapid improvement in the clinical condition of patients treated with JAK inhibitors is due to their direct impact on the modulation of the pathogenesis of the disease. The predictable benefits of therapy outweigh the side effects which can be detected at an early stage with regular monitoring of the patient.

Discovery of a potent and selective JAK1-targeting PROTAC degrader with anti-tumor activities

Aberrant activation of the JAK-STAT pathway is evident in various human diseases including cancers. Proteolysis targeting chimeras (PROTACs) provide an attractive strategy for developing novel JAK-targeting drugs. Herein, a series of CRBN-directed JAK-targeting PROTACs were designed and synthesized utilizing a JAK1/JAK2 dual inhibitor—momelotinib as the warhead. The most promising compound 10c exhibited both good enzymatic potency and cellular antiproliferative effects. Western blot analysis revealed that compound 10c effectively and selectively degraded JAK1 in a proteasome-dependent manner (DC50 = 214 nM). Moreover, PROTAC 10c significantly suppressed JAK1 and its key downstream signaling. Together, compound 10c may serve as a novel lead compound for antitumor drug discovery.

Use of IL-3RB to mediate antitumor effect of CAR-T cells through the JAK-STAT signaling pathway.

2541 Background: The application of CAR-T in solid tumors has not yet demonstrated significant clinical benefits. The continuous proliferation and decreased terminal differentiation of CAR-T cells in vivo are considered potential strategies that could alter this predicament. Cytokines, as the 3rd signal for T-cell activation, play a crucial role in the lifecycle and fate of T cells. In this study, we innovatively incorporated the IL-3 receptor β chain (IL-3RB) into the CAR structure to enhance signal transduction, potentially activating the anti-tumor function of CAR-T and maintaining the persistent proliferative activity. Methods: Transcriptional profiling analysis performed on HER2 or VEGFR1 CAR-T cells, with a specific focus on the gp140 cytokine family (IL-3/IL-5/CSF-2) and the receptor expression, validated by ELISA and Western blot. By cloning CAR genes containing different structural domains of the IL-3RB into the lentiviral vector pWPXLd, CAR expression, activation, depletion, proliferation, cytotoxicity, pSTAT3 and pSTAT5, and cytokine release of CAR-T cells were assessed using flow cytometry (FCM), Western blot (WB), RTCA, CCK-8, and ELISA. Subcutaneous/abdominal injections of SKOV3 cells or SKOV3-Luc cells into NSG mice, followed treated by CAR-T cells. Tumor burden was regularly monitored, and FCM and Q-PCR were utilized to assess the quantity and phenotype of CAR-T cells in vivo. Results: RNA-sequence, ELISA and WB revealed that upon activation of CAR-T cells, the expression of genes such as IL-3/IL-5/CSF-2 rapidly increased. However, their receptors were hardly expressed. IL-3RB modification did not affect the phenotype of resting CAR-T cells. But, co-cultured with target cells, IL-3RB significantly enhanced the anti-tumor effects of CAR-T cells. This was manifested by more rapid activation, promotion of persistent proliferation, delayed exhaustion phenotype, secretion of higher levels of cytokines (IL-2, IFN-γ, TNF-α) and efficient cytotoxicity. IL-3RB-expressing CAR-T cells exhibited activation of the JAK kinase and STAT3, STAT5 transcription factor signaling pathways in vitro. We established solid tumor models of subcutaneous (SKOV3) and intraperitoneal metastasis, where HER2/VEGFR1 CAR-T cells partially inhibited tumor cell growth in vivo. In contrast, IL-3RB-enhanced CAR-T cells completely eradicated tumor cells, and even achieving a state of complete remission. FCM and Q-PCR also confirmed that IL-3RB significantly improved the proliferation and survival of CAR-T cells in vivo. Conclusions: IL-3RB is scarcely expressed in T cells and not regulated by T cell activation. IL-3RB-modified CAR-T cells exhibit superior persistence and significant anti-tumor advantages in a solid tumor through the JAK-STAT signaling pathway. Our innovative CAR structure design has the potential to demonstrate promising anti-tumor effects in clinical translational applications.

Transcriptome-based network analysis reveals hub immune genes and pathways of hepatopancreas against LPS in Amphioctopus fangsiao

The hepatopancreas is the biggest digestive organ in Amphioctopus fangsiao (A. fangsiao), but also undertakes critical functions like detoxification and immune defense. Generally, pathogenic bacteria or endotoxin from the gut microbiota would be arrested and detoxified in the hepatopancreas, which could be accompanied by the inevitable immune responses. In recent years, studies related to cephalopods immune have been increasing, but the molecular mechanisms associated with the hepatopancreatic immunity are still unclear. In this study, lipopolysaccharide (LPS), a major component of the cell wall of Gram-negative bacteria, was used for imitating bacteria infection to stimulate the hepatopancreas of A. fangsiao. To investigate the immune process happened in A. fangsiao hepatopancreas, we performed transcriptome analysis of hepatopancreas tissue after LPS injection, and identified 2615 and 1943 differentially expressed genes (DEGs) at 6 and 24 h post-injection, respectively. GO and KEGG enrichment analysis showed that these DEGs were mainly involved in immune-related biological processes and signaling pathways, including ECM-receptor interaction signaling pathway, Phagosome signaling pathway, Lysosome signaling pathway, and JAK-STAT signaling pathways. The function relationships between these DEGs were further analyzed through protein-protein interaction (PPI) networks. It was found that Mtor, Mapk14 and Atm were the three top interacting DEGs under LPS stimulation. Finally, 15 hub genes involving multiple KEGG signaling pathways and PPI relationships were selected for qRT-PCR validation. In this study, for the first time we explored the molecular mechanisms associated with hepatopancreatic immunity in A. fangsiao using a PPI networks approach, and provided new insights for understanding hepatopancreatic immunity in A. fangsiao.

Bioinformatics and experimental approach identify lipocalin 2 as a diagnostic and prognostic indicator for lung adenocarcinoma

Backgroundlipocalin 2 (LCN2) is a secreted glycoprotein that plays key roles in tumorigenesis and progression. Interestingly, LCN2 appears to have a contradictory function in developing lung adenocarcinoma (LUAD). Thus, we intend to explore the role of LCN2 in LUAD through bioinformatics and experimental validation. MethodsLCN2 expression of LUAD was investigated in the TCGA, TIMER and HPA databases. The relationship between LCN2 and prognosis was investigated by KM plotter, TCGA and GEO databases. GO, KEGG and protein-protein interactions network analysis were conducted to investigate the potential mechanism of LCN2. The relevance of LCN2 to cancer-immune infiltrates was investigated in the TCGA and TIMER databases. Quantitative reverse transcription PCR, western blot and enzyme-linked immunosorbent assay were performed to identify the expression level of LCN2 in cells and serum samples. The CCK-8, wound healing and transwell assay were used to confirm the effect of LCN2 on cell proliferation, migration and invasion in LUAD. The receiver operating characteristic curve was utilized to assess the diagnostic efficiency of LCN2 further. ResultsLCN2 expression was significantly upregulated in LUAD (P < 0.05), and was correlated with the clinical stage, tumor size, lymph node metastasis and distant metastasis (P < 0.05). There was a high correlation between high LCN2 and worse prognosis in LUAD. Functional network analysis suggested that LCN2 was associated with multiple signal pathways in cancers, such as JAK-STAT, TNF, NF-κB, HIF-1 and PI3K-Akt signal pathways. In addition, the knockdown of LCN2 significantly inhibited the ability of cell proliferation, migration and invasion. Immune infiltration analysis indicated that LCN2 is associated with multiple immune cell infiltration. Notably, LCN2 demonstrated high diagnostic efficiency for LUAD (AUC = 0.818, P < 0.05), especially for stage III-IV patients could reach 0.895. ConclusionsLCN2 as an oncogenic glycoprotein promotes the cancer progression related to immune infiltrates, which might be a potential diagnostic and prognostic marker in LUAD.