The molecular basis of JAK/STAT inhibition by SOCS1

Topical delgocitinib for the treatment of chronic hand eczema

PURPOSE

Chronic hand eczema (CHE) is a prevalent dermatological condition characterized by significant morbidity and impaired quality of life. Delgocitinib, a pan-JAK inhibitor, has emerged as a promising topical treatment for CHE, targeting key cytokine-mediated inflammatory pathways involved in the disease. Delgocitinib 20 mg/g (2%) cream was approved by the European Medicines Agency (EMA) in 2024 for moderate-to-severe CHE, and its U.S. Food and Drug Administration (FDA) review is currently in progress.

MATERIALS AND METHODS

PubMed, Medline and ClinicalTrials.gov were searched up to January 21, 2025, using specific search terms related to delgocitinib and chronic hand eczema.

RESULTS AND CONCLUSIONS

Clinical trials have demonstrated its effectiveness in improving disease severity, including eczema signs and symptoms such as pain and itching, and enhancing patient-reported outcomes compared to vehicle. Topical delgocitinib has shown a favorable safety profile, with most adverse events being mild and unrelated to treatment. Serious adverse events were rare, and treatment discontinuation due to adverse events was minimal. This narrative review synthesizes current evidence on topical delgocitinib's clinical utility and safety in CHE, positioning it as a valuable therapeutic option. Further comparative studies are needed to evaluate its efficacy against oral JAK inhibitors and other topical immunosuppressants, providing insight into optimizing treatment strategies for this chronic condition.

Exploring the novel role and mechanistic insights of skeletal muscle relaxant cyclobenzaprine hydrochloride in esophageal squamous cell carcinoma treatment

OBJECTIVE

Cyclobenzaprine hydrochloride (Flexeril) is a muscle relaxant primarily used to relieve muscle pain and spasms. However, its potential anti-cancer role remains largely unexplored. This study aims to investigate the inhibitory effect of Flexeril on esophageal squamous cell carcinoma (ESCC) and to uncover the molecular mechanisms through which it affects the proliferation and metastasis of ESCC.

METHODS

A compound library approved by the FDA was employed to screen drugs with inhibitory effects on ESCC. Cell viability was assessed using the Cell Counting Kit-8 (CCK-8) assay, and Plate colony formation was analyzed to evaluate the proliferative ability of ESCC cell lines (KYSE150 and Eca109) after treatment with Flexeril. Migratory ability was examined through Transwell and Scratch assays. Proteomics was performed to identify proteins regulated by Flexeril in KYSE150 and Eca109 cells. RT-PCR and Western blot were used to detect changes in related genes at the mRNA and protein levels after treatment with Flexeril. Drug affinity responsive target stability (DARTS) assay and cellular thermal shift assay (CETSA) were employed to identify the binding of Flexeril and JAK1 protein. Additionally, the comet assay was conducted to assess the DNA damage response in ESCC cells following WDHD1 knockdown or Flexeril exposure. Finally, tumor‑bearing nude mice model were constructed to evaluate the in vivo anticancer effects of Flexeril on ESCC.

RESULTS

Flexeril significantly inhibited the proliferation and migration of ESCC cells in a time- and dose-dependent manner. Proteomics analysis identified WDHD1 as a downstream target of Flexeril exposure, and knockdown of WDHD1 mimicked the effects of Flexeril on proliferation and migration of ESCC. Conversely, overexpression of WDHD1 attenuated the inhibitory effects of Flexeril on ESCC. Mechanistically, the JAK1-STAT3 signaling pathway, but not the JAK2-STAT3 or PI3K-Akt-mTOR pathways, was involved in regulating WDHD1 expression in ESCC cells following Flexeril treatment. Overexpression of STAT3 or WDHD1 mitigated the inhibitory effects of Flexeril on ESCC proliferation and migration. Moreover, both Flexeril exposure and WDHD1 knockdown induced a DNA damage response (DDR) in ESCC cells. In addition, Flexeril significantly inhibited the growth of ESCC tumors in nude mice, downregulating the JAK1-STAT3-WDHD1 signaling pathway, with no significant damage observed in vital organs such as the heart, liver, spleen, lungs, or kidneys, as shown by histological examination.

CONCLUSION

Flexeril exhibits anti-cancer effects in ESCC by inhibiting the JAK1-STAT3-WDHD1 axis and inducing DDR. These findings suggest that Flexeril may serve as a potential novel therapeutic agent for the treatment of ESCC.

Toxic effects and transcriptome analysis of the early life stages of Larimichthys crocea exposed to the bloom-forming dinoflagellate Alexandrium tamarense

This study investigated the effects of the bloom-forming dinoflagellate Alexandrium tamarense and its potentially associated paralytic shellfish toxins on the early life stages of Larimichthys crocea (large yellow croaker) by integrating physiological effects with transcriptomic analysis to explore the molecular mechanisms underlying these harmful impacts. The results showed that 48-h acute exposure to A. tamarense culture and cell-free filtrate significantly reduced the heart rate in embryos and increased mortality rates in both embryos and larvae. Transcriptome sequencing of the filtrate-exposed group identified 130 differentially expressed genes in the embryo group and 884 in the juvenile group. Further analysis revealed that algal exposure triggered the activation of innate immunity in embryos, as evidenced by the significant upregulation of immune-related cytokines such as CCL20, IL11, and ILRA10. These genes were enriched in the cytokine-cytokine receptor interaction pathway and may induce immune responses through their respective downstream pathways. Additionally, the downregulation of the RNA polymerase and ribosome pathways suggests that protein synthesis was affected during the embryo stress response induced by A. tamarense. In juveniles, genes related to cardiac function, particularly those associated with myocardial contraction and calcium ion regulation, were downregulated after exposure to algal filtrate, further suggesting that A. tamarense, possibly through paralytic shellfish toxins, inhibits the heart function of L. crocea. The findings of this study elucidate the toxicological mechanisms of A. tamarense on the early life stages of L. crocea, providing scientific evidence for the impact of harmful algal blooms on marine life health and offering valuable insights for management strategies in aquaculture.

miR-155 targets SOCS1 to modulate the phenotype transition of M1 macrophage in distraction osteogenesis promoted by PTH administration

BACKGROUND

Distraction osteogenesis (DO) is a highly effective method for bone regeneration. However, its prolonged treatment duration limits its clinical application. Parathyroid hormone (PTH) can promote distraction osteogenesis, but the underlying mechanism remains unclear. During distraction osteogenesis, macrophages modulate inflammation after phenotypic transition, promoting bone regeneration. PTH is known to affect the expression of specific miRNAs, and miR-155 has been shown to regulate macrophage polarization, with subsequent effects on inflammation. We hypothesized that miR-155 may participate in the osteogenic effect of PTH by regulating macrophage polarization. In this study, we aim to explored the mechanism by which PTH promotes distraction osteogenesis using both in vivo and in vitro models.

METHODS

Established a rabbit model of mandibular distraction osteogenesis in which histomorphological observations confirmed the osteogenic effects of PTH and the reduced expression of miR-155. In addition, a lipopolysaccharide (LPS)-induced macrophage distraction model was established. ELISA was used to measure the expression of the inflammatory cytokines TNF-α and IL-1β in animal serum and cell supernatants. RT‒qPCR was used to detect the expression of miR-155 and SOCS1, and Western blotting and IHC were used to examine SOCS1 expression and explore its mechanisms. The overexpression of miR-155, the proportion of M1 macrophages was reassessed, and the expressions of SOCS1, TNF-α, and IL-1β were concurrently evaluated.

RESULTS

PTH administration significantly downregulated miR-155 expression in both the rabbit model and in vitro macrophages. This led to an upregulation of SOCS1 expression, which in turn reduced the polarization of M1 macrophages. The levels of TNF-α and IL-1β were also markedly reduced in the PTH-treated groups compared to the control groups. In the distraction zone, histological analysis revealed that the experimental group had better trabecular bone formation, with higher density and maturity of trabeculae compared to the control group. Flow cytometry analysis showed a significant reduction in the proportion of M1 macrophages in PTH-treated cells. The dual-luciferase reporter assay confirmed that miR-155 directly targets SOCS1.

CONCLUSIONS

PTH downregulates miR-155 in new bone and macrophages during mandibular DO, increasing SOCS1 expression, reducing M1 macrophages, and enhancing bone regeneration by lowering inflammation.

Integrative genomic analysis of DLBCL identifies immune environments associated with bispecific antibody response

ABSTRACT

Most patients with diffuse large B-cell lymphoma (DLBCL) treated with immunotherapies such as bispecific antibodies (BsAbs) or chimeric antigen receptor (CAR) T cells fail to achieve durable treatment responses, underscoring the need for a deeper understanding of mechanisms that regulate the immune environment and response to treatment. Here, an integrative multiomics approach was applied to multiple large independent data sets to characterize DLBCL immune environments and to define their association with tumor cell-intrinsic genomic alterations and outcomes to CD19-directed CAR T-cell and CD20 × CD3 BsAb therapies. This approach effectively segregated DLBCLs into 4 immune quadrants (IQs) defined by cell-of-origin and immune-related gene set expression scores. These quadrants consisted of activated B cell-like (ABC) hot, ABC cold, germinal center B cell-like (GCB) hot, and GCB cold DLBCLs. Recurrent genomic alterations were enriched in each IQ, suggesting that lymphoma cell-intrinsic alterations contribute significantly to orchestrating unique DLBCL immune environments. For instance, SOCS1 loss-of-function mutations were significantly enriched among GCB hot DLBCLs, identifying a putative subset of inflamed DLBCLs that may be inherently susceptible to immunotherapy. In patients with relapsed/refractory DLBCL, DLBCL-IQ assignment correlated significantly with clinical benefit with a CD20 × CD3 BsAb (N = 74), but not with CD19-directed CAR T cells (Stanford, N = 51; Memorial Sloan Kettering Cancer Center, N = 69). Thus, DLBCL-IQ provides a new framework to conceptualize the DLBCL immune landscape and suggests the endogenous immune environment has a more significant impact on outcomes to BsAb than CAR T-cell treatment.

Recent advances and future perspectives in small molecule JAK2 inhibitors

The Janus kinase (JAK)/Signal Transducer and Activator of Transcription (STAT) signaling pathway is essential for controlling immune function, blood cell formation, and cell growth. Dysregulation of this pathway is implicated in various diseases, including hematologic malignancies, autoimmune disorders, and chronic inflammatory conditions. This review provides a comprehensive overview of the structural and functional aspects of JAK/STAT signaling, with a particular focus on the role of JAK2. This manuscript explores the primary regulators of the JAK/STAT pathway, such as Suppressors Of Cytokine Signaling (SOCS), Protein Inhibitors of Activated STATs (PIAS), and Protein Tyrosine Phosphatases (PTPs), which play a crucial role in maintaining cellular balance and stability. Additionally, the therapeutic landscape of JAK2 inhibitors is explored, covering both approved and investigational drugs, including their mechanisms of action, efficacy, and safety profiles. Emerging strategies such as drug repositioning using computational approaches and experimental validation are also highlighted. By integrating insights from molecular docking studies, machine learning models, and kinase assays, this review emphasizes the potential of JAK2 inhibitors in disease management.

Expanded T cell clones with lymphoma driver somatic mutations accumulate in refractory celiac disease

Intestinal inflammation continues in a subset of patients with celiac disease despite a gluten-free diet. Here, by applying multi-omic single-cell analysis to duodenal biopsies, we found that low-grade malignancies with lymphoma driver mutations in patients with refractory celiac disease type 2 (RCD2) are comprised by surface CD3-negative (sCD3-) lymphocytes stalled at an innate lymphoid cell (ILC)-progenitor T cell stage undergoing extensive TRA, TRB, and TRD TCR recombination. In people with refractory celiac disease type 1 (RCD1), a disease currently lacking explanation, we identified sCD3+ T cells with lymphoma driver mutations in 6 of 10 individuals with RCD1 and in one of the patients with active, recently diagnosed celiac disease. Furthermore, the mutant T cells formed large TCRαβ clones and displayed inflammatory and cytotoxic molecular profiles. Thus, accumulation of lymphoma driver-mutated T cells and sCD3- progenitors may contribute to chronic, nonresponsive celiac disease.

Baicalin mitigates alcoholic-associated liver disease via SOCS1-driven reprogramming of macrophages

BACKGROUNDS

Alcoholic liver disease (ALD), a consequence of excessive alcohol consumption, is characterized by high incidence and mortality rates. Presently, there are no effective pharmacological interventions available for the treatment of ALD. Baicalin (BA), a natural flavonoid derived from the root of Scutellaria baicalensis, has exhibited notable hepatoprotective effects. Nevertheless, the mechanisms through which BA influences the interaction between suppressor of cytokine signaling 1 (SOCS1) and macrophages during hepatic immune development remain insufficiently understood.

MATERIALS AND METHODS

This study seeks to examine the regulatory effects of BA on ALD and to elucidate the relationship between SOCS1 and macrophage differentiation. Our experimental methodology involves the novel application of zebrafish as an in vivo model for ALD. To further investigate the underlying mechanisms, we employed gene knockout and overexpression techniques.

RESULTS

The study demonstrates that BA substantially alleviates ALD in both in vivo and in vitro settings by upregulating SOCS1 expression in macrophages. Furthermore, we elucidated the association between SOCS1 and macrophage reprogramming. Specifically, SOCS1 knockdown led to the downregulation of CD86, CD80, and iNOS expression, whereas SOCS1 overexpression enhanced the expression of CD206, CD163, IL-4, and IL-10.

CONCLUSION

In conclusion, our findings suggest that BA attenuates ALD via the modulation of SOCS1-mediated macrophage reprogramming.

Development of SOCS1 mimetics as novel approach to harmonize inflammation, oxidative stress, and fibrogenesis in metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prevalent chronic liver disease, encompassing a spectrum from simple steatosis to steatohepatitis (MASH), cirrhosis, and hepatocellular carcinoma. As part of metabolic syndrome, MASLD/MASH is characterized by inflammation, oxidative stress, and fibrosis, highlighting the need for targeted therapies. The dysregulation of Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway and its negative regulators the suppressors of cytokine signaling (SOCS), plays a critical role in liver function and contributes to MASLD progression.

AIM

Based on a SOCS1 functional domain, we developed mimetic peptides (linear and cyclic) targeting JAK activity and assessed their hepatoprotective potential in experimental MASLD/MASH.

RESULTS

In dietary mouse models of MASLD/MASH, the administration of peptides ameliorated liver damage at both early and advanced stages, as evidenced by significant decreases in serum transaminases and hepatic content of lipids, inflammatory cells, and collagen. Treatment attenuated hepatic STAT1/3 activation and downregulated genes involved in inflammation, fibrosis, and lipid metabolism. Livers from treated mice exhibited lower levels of oxidative damage markers, reduced expression of NADPH oxidase 1 (NOX1), and upregulation of the antioxidant genes catalase and superoxide dismutase. In vitro, the peptides were safe for hepatocytes at different doses and effectively counteracted palmitate-induced cytotoxicity, superoxide anion production, and cytokine and NOX1 expression, while increasing anti-inflammatory and antioxidant genes.

CONCLUSIONS

SOCS1 mimetic peptides exhibit hepatoprotective effects in experimental MASLD/MASH by modulating lipotoxicity, inflammation, redox balance and fibrogenesis. This proof-of-concept supports their potential as candidates for preclinical MASLD therapy development.

JAK-STAT Signaling in Autoimmunity and Cancer

The JAK-STAT pathway is an essential cell survival signaling that regulates gene expressions related to inflammation, immunity and cancer. Cytokine receptors, signal transducer and activator of transcription (STAT) proteins, and Janus kinases (JAKs) are the critical component of this signaling cascade. When JAKs are stimulated by cytokines, STAT phosphorylation, dimerization, and nuclear translocation occur, which eventually impacts gene transcription. Dysregulation of JAK-STAT signaling is linked with various autoimmune diseases, including rheumatoid arthritis, psoriasis, and inflammatory bowel disease. This pathway is constitutively activated in human malignancies and leads to tumor cell survival, proliferation, and immune evasion. Oncogenic mutations in the JAK and STAT genes have been found in solid tumors, leukemia, and lymphoma. Targeting the JAK-STAT pathway is a viable and promising therapeutic strategy for the treatment of autoimmune diseases and cancers.

New insight into the role of SOCS family in immune regulation and autoimmune pathogenesis

BACKGROUND

Suppressor of cytokine signaling (SOCS) proteins regulate signal transduction by interacting with cytokine receptors and signaling proteins and targeting associated proteins for degradation. Recent studies have demonstrated that the SOCS proteins serve as crucial inhibitors in cytokine signaling networks and play a pivotal role in both innate and adaptive immune responses.

AIM OF REVIEW

In this review, we aim to discuss recent advancements in understanding the complex functions of SOCS proteins in various immune cells, as well as the effects of SOCS proteins in human health and diseases. Increasing evidence indicates that SOCS proteins are frequently dysregulated in developing autoimmune diseases, suggesting that therapeutic targeting of SOCS proteins could provide clinical benefit.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review provides a comprehensive understanding of SOCS proteins in immune regulation and autoimmune pathogenesis, it also highlights the role of SOCS-related mimetic peptides in immunotherapy.

SOCS1 Protects Acute Myeloid Leukemia against Allogeneic T Cell-Mediated Cytotoxicity

SIGNIFICANCE

Our investigation of the SOCS1 pathway in AML and T-cell interactions provides insights into potential mechanisms of resistance of AML to allogeneic hematopoietic stem cell transplantation and demonstrates the potential of targeting SOCS1 and its downstream mediators to enhance antileukemic T-cell activity. See related commentary by Fry, p. 157.

Oligonucleotide-Based Modulation of Macrophage Polarization: Emerging Strategies in Immunotherapy

BACKGROUND

Recent advances in immunotherapy have spotlighted macrophages as central mediators of disease treatment. Their polarization into pro‑inflammatory (M1) or anti‑inflammatory (M2) states critically influences outcomes in cancer, autoimmunity, and chronic inflammation. Oligonucleotides have emerged as highly specific, scalable, and cost‑effective agents for reprogramming macrophage phenotypes.

OBJECTIVE

To review oligonucleotide strategies-including ASOs, siRNAs, miRNA mimics/inhibitors, and aptamers-for directing macrophage polarization and their therapeutic implications.

REVIEW SCOPE

We examine key signaling pathways governing M1/M2 phenotypes, describe four classes of oligonucleotides and their mechanisms, and highlight representative preclinical and clinical applications.

KEY INSIGHTS

Agents such as AZD9150, MRX34, and AS1411 demonstrate macrophage reprogramming in cancer, inflammation, and infection models. Advances in ligand‑conjugated nanoparticles and chemical modifications improve delivery and stability, yet immunogenicity, off‑target effects, and formulation challenges remain significant barriers.

FUTURE PERSPECTIVES

Optimizing delivery platforms, enhancing molecular stability, and rigorous safety profiling are critical. Integration with emerging modalities-such as engineered CAR‑macrophages-will enable precise, disease‑specific interventions, and advance oligonucleotide‑guided macrophage modulation toward clinical translation.

Immunomodulatory peptide DP7-C mediates macrophage-derived exosomal miR-21b to promote bone regeneration via the SOCS1/JAK2/STAT3 axis

Periodontitis, the most prevalent chronic inflammatory disease leading to bone resorption, presents significant challenges for achieving optimal periodontal bone regeneration and repair despite efforts to reduce inflammation and stimulate osteogenesis. Macrophage-derived exosomes have emerged as promising therapeutic agents due to their osteogenic and immunomodulatory potential. Specific stimulation of macrophages can alter the exosomal composition, particularly microRNAs (miRNAs), thereby altering their functions. DP7-C, a cationic immunomodulatory peptide, is known to regulate immune responses and cellular processes by interacting with cell membranes and signaling pathways. However, its effects on macrophage exosomal miRNA profiles remain poorly understood. In this study, we identified differential miRNA expression in macrophage-derived exosomes following DP7-C stimulation, with a notable upregulation of miR-21b. To investigate the osteogenic role of exosomal miR-21b, DP7-C was utilized to facilitate the transfection of miR-21b into macrophages, leading to the secretion of exosomes enriched with miR-21b. These exosomes enhanced osteogenic differentiation in vitro and alleviated periodontal tissue damage in an experimental periodontitis model in vivo. Mechanistically, exosomal miR-21b promotes osteogenesis by directly targeting the suppressor of cytokine signaling (SOCS1), thereby activating the JAK2/STAT3 signaling pathway. This study establishes macrophage-derived exosomal miR-21b as a potent catalyst for bone regeneration, highlighting a promising acellular therapeutic strategy for periodontitis.

Protein Kinases as Mediators for miRNA Modulation of Neuropathic Pain

Neuropathic pain is a chronic condition resulting from injury or dysfunction in the somatosensory nervous system, which leads to persistent pain and a significant impairment of quality of life. Research has highlighted the complex molecular mechanisms that underlie neuropathic pain and has begun to delineate the roles of microRNAs (miRNAs) in modulating pain pathways. miRNAs, which are small non-coding RNAs that regulate gene expression post-transcriptionally, have been shown to influence key cellular processes, including neuroinflammation, neuronal excitability, and synaptic plasticity. These processes contribute to the persistence of neuropathic pain, and miRNAs have emerged as critical regulators of pain behaviors by modulating signaling pathways that control pain sensitivity. miRNAs can influence neuropathic pain by targeting genes that encode protein kinases involved in pain signaling. This review focuses on miRNAs that have been demonstrated to modulate neuropathic pain behavior through their effects on protein kinases or their immediate upstream regulators. The relationship between miRNAs and neuropathic pain behaviors is characterized as either an upregulation or a downregulation of miRNA levels that leads to a reduction in neuropathic pain. In the case of miRNA upregulation resulting in an alleviation of neuropathic pain behaviors, protein kinases exhibit a positive correlation with neuropathic pain, whereas decreased protein kinase levels correlate with diminished neuropathic pain behaviors. The only exception is GRK2, which shows an inverse correlation with neuropathic pain. In the case of miRNA downregulation resulting in a reduction in neuropathic pain behaviors, protein kinases display mixed relationships to neuropathic pain, with some kinases exhibiting positive correlation, while others exhibit negative correlation. By exploring how protein kinases mediate miRNA modulation of neuropathic pain, valuable insight may be gained into the pathophysiology of neuropathic pain, offering potential therapeutic targets for developing more effective strategies for pain management.

JAK-STAT pathway, type I/II cytokines, and new potential therapeutic strategy for autoimmune bullous diseases: update on pemphigus vulgaris and bullous pemphigoid

Autoimmune Bullous Diseases (AIBDs), characterized by the formation of blisters due to autoantibodies targeting structural proteins, pose significant therapeutic challenges. Current treatments, often involving glucocorticoids or traditional immunosuppressants, are limited by their non-specificity and side effects. Cytokines play a pivotal role in AIBDs pathogenesis by driving inflammation and immune responses. The JAK-STAT pathway is central to the biological effects of various type I and II cytokines, making it an attractive therapeutic target. Preliminary reports suggest that JAK inhibitors may be a promising approach in PV and BP, but further clinical validation is required. In AIBDs, particularly bullous pemphigoid (BP) and pemphigus vulgaris (PV), JAK inhibitors have shown promise in modulating pathogenic cytokine signaling. However, the safety and selectivity of JAK inhibitors remain critical considerations, with the potential for adverse effects and the need for tailored treatment strategies. This review explores the role of cytokines and the JAK-STAT pathway in BP and PV, evaluating the therapeutic potential and challenges associated with JAK inhibitors in managing these complex disorders.

Cytokines in Focus: IL-2 and IL-15 in NK Adoptive Cell Cancer Immunotherapy

NK cell adoptive cell therapy (ACT) has emerged as a promising strategy for cancer immunotherapy, offering advantages in scalability, accessibility, efficacy, and safety. Ex vivo activation and expansion protocols, incorporating feeder cells and cytokine cocktails, have enabled the production of highly functional NK cells in clinically relevant quantities. Advances in NK cell engineering, including CRISPR-mediated gene editing and chimeric Ag receptor technologies, have further enhanced cytotoxicity, persistence, and tumor targeting. Cytokine support post-adoptive transfer, particularly with IL-2 and IL-15, remains critical for promoting NK cell survival, proliferation, and anti-tumor activity despite persistent challenges such as regulatory T cell expansion and cytokine-related toxicities. This review explores the evolving roles of IL-2 and IL-15 in NK cell-based ACT, evaluating their potential and limitations, and highlights strategies to optimize these cytokines for effective cancer immunotherapy.

IL-4 mediated TAP2 downregulation is a dominant and reversible mechanism of immune evasion and immunotherapy resistance in non-small cell lung cancer

BACKGROUND

Resistance to both naturally occurring anti-cancer immunity and to immunotherapy is common in patients with aggressive non-small cell lung cancer (NSCLC). Recent studies indicate a role of loss of the HLA class-I antigen presentation machinery (APM) protein β-2-microglobulin in acquired resistance to immune checkpoint blockers. However, the mechanisms, functional consequences and therapeutic potential of APM defects in NSCLC remain poorly understood.

METHODS

Using multiplexed immunofluorescence, we spatially mapped CD8+ effector Tumor-Infiltrating Lymphocytes (TILs) and the APM components TAP1 and TAP2 in 819 baseline/pre-treatment NSCLCs from patients treated with and without PD-1 axis blockers in 4 independent cohorts. The impact of TAP1/2 silencing in lung cancer cells using siRNAs and CRISPR/Cas9 was studied using transcriptomic analysis, phosphoprotein arrays, ATAC-sequencing, measurement of surface HLA-peptide complexes and in vitro tumor-antigen specific T-cell killing. We established autologous co-cultures of tumor and immune cells from primary human NSCLCs to study the functional impact of IL4Rα and/or PD-1 blockade using monoclonal antibodies. A high-throughput drug screen supported the identification of compounds able to increase TAP2 expression in NSCLC cells.

RESULTS

We identified cancer cell selective TAP2 protein downregulation in 42.4% of treatment naïve NSCLCs associated with reduced sensitivity to immune checkpoint blockers. TAP1 downregulation occurred in 24.4% of lung tumors without survival impact. Silencing of TAP2 in lung cancer cells altered key intracellular immunomodulatory pathways, limited sensitivity to proinflammatory cytokines, reduced the levels of surface peptide-HLA complexes and protected malignant cells from tumor antigen-specific T-cell killing via SOCS1 upregulation. TAP2 loss in human NSCLCs was associated with reduced TAP2 promoter chromatin accessibility and elevated IL-4 IL-4 expression. Treatment with IL-4 reduced TAP2 levels and the chromatin accessibility of the TAP2 gene promoter in NSCLC cells and reproduced all the functional consequences of TAP2 loss. In intact human NSCLC, IL-4 IL-4 transcripts were detected in intratumoral myeloid cells and IL-4Rα blockade increased human NSCLC cell killing by autologous TILs. Epigenetic modulators and other drugs with known anti-cancer activity increased TAP2 expression and its function in lung cancer cells.

CONCLUSIONS

Our study reveals previously unrecognized functions of TAP2 beyond antigen presentation and establishes a reversible multi-cellular axis mediating adaptive immune evasion and immunotherapy resistance with clinical potential.

Cullin-5 controls the number of megakaryocyte-committed stem cells to prevent thrombocytosis in mice

ABSTRACT

Cullin-5 (Cul5) coordinates the assembly of cullin-RING-E3 ubiquitin ligase complexes that include the suppressors of cytokine signaling (SOCS)-box-containing proteins. The SOCS-box proteins function to recruit specific substrates to the complex for ubiquitination and degradation. In hematopoiesis, SOCS-box proteins are best known for regulating the actions of cytokines that utilize the JAK-STAT signaling pathway. However, the roles of most SOCS-box proteins have not been studied in physiological contexts and any actions for Cul5/SOCS complexes in signaling by several hematopoietic cytokines, including thrombopoietin (TPO) and interleukin-3 (IL-3), remain unknown. To define additional potential roles for Cul5/SOCS complexes, we generated mice lacking Cul5 in hematopoiesis; the absence of Cul5 is predicted to impair the SOCS-box-dependent actions of all proteins that contain this motif. Here, we show that Cul5-deficient mice develop excess megakaryopoiesis and thrombocytosis revealing a novel mechanism of negative regulation of megakaryocyte-committed stem cells, a distinct population within the hematopoietic stem cell pool that have been shown to rapidly, perhaps directly, generate megakaryocytes, and which are produced in excess in the absence of Cul5. Cul5-deficient megakaryopoiesis is distinctive in being largely independent of TPO/myeloproliferative leukemia protein and involves signaling via the β-common and/or β-IL-3 receptors, with evidence of deregulated responses to IL-3. This process is independent of the interferon-α/β receptor, previously implicated in inflammation-induced activation of stem-like megakaryocyte progenitor cells.

The multi-faceted roles of cancer-associated fibroblasts in pancreatic cancer

The tumor microenvironment (TME) has been linked with the pathogenesis of pancreatic ductal adenocarcinoma (PDAC), the most common histological subtype of pancreatic cancer. A central component of the TME are cancer-associated fibroblasts (CAFs), which can either suppress or promote tumor growth in a context-dependent manner. In this review, we will discuss the multi-faceted roles of CAFs in tumor-stroma interactions influencing cancer initiation, progression and therapeutic response.

Data-driven projections of candidate enhancer-activating SNPs in immune regulation

BACKGROUND

Millions of single nucleotide polymorphisms (SNPs) have been identified in humans, but the functionality of almost all SNPs remains unclear. While current research focuses primarily on SNPs altering one amino acid to another one, the majority of SNPs are located in intergenic spaces. Some of these SNPs can be found in candidate cis-regulatory elements (CREs) such as promoters and enhancers, potentially destroying or creating DNA-binding motifs for transcription factors (TFs) and, hence, deregulating the expression of nearby genes. These aspects are understudied due to the sheer number of SNPs and TF binding motifs, making it challenging to identify SNPs that yield phenotypic changes or altered gene expression.

RESULTS

We developed a data-driven computational protocol to prioritize high-potential SNPs informed from former knowledge for experimental validation. We evaluated the protocol by investigating SNPs in CREs in the Janus kinase (JAK) - Signal Transducer and Activator of Transcription (-STAT) signaling pathway, which is activated by a plethora of cytokines and crucial in controlling immune responses and has been implicated in diseases like cancer, autoimmune disorders, and responses to viral infections. The protocol involves scanning the entire human genome (hg38) to pinpoint DNA sequences that deviate by only one nucleotide from the canonical binding sites (TTCnnnGAA) for STAT TFs. We narrowed down from an initial pool of 3,301,512 SNPs across 17,039,967 nearly complete STAT motifs and identified six potential gain-of-function SNPs in regions likely to influence regulation within the JAK-STAT pathway. This selection was guided by publicly available open chromatin and gene expression data and further refined by filtering for proximity to immune response genes and conservation between the mouse and human genomes.

CONCLUSION

Our findings highlight the value of combining genomic, epigenomic, and cross-species conservation data to effectively narrow down millions of SNPs to a smaller number with a high potential to induce interferon regulation of nearby genes. These SNPs can finally be reviewed manually, laying the groundwork for a more focused and efficient exploration of regulatory SNPs in an experimental setting.

Natural products for the treatment of ulcerative colitis: focus on the JAK/STAT pathway

Ulcerative colitis (UC) is an autoimmune disease with an incompletely understood pathogenesis. The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway plays a key role in immune response and inflammation. More and more studies demonstrated that JAK/STAT signaling pathway is associated with the pathogenesis of UC. The JAK/STAT pathway affects UC in multiple ways by regulating intestinal inflammatory response, affecting intestinal mucosal barrier, modulating T cell homeostasis, and regulating macrophages. Encouragingly, natural products are promising candidates for the treatment of UC. Natural products have the advantage of being multi-targeted and rich in therapeutic modalities. This review summarized the research progress of JAK/STAT pathway-mediated UC. Furthermore, the latest studies on natural products targeting the JAK/STAT pathway for the treatment of UC were systematically summarized, including active ingredients such as arbutin, aloe polysaccharide, berberine, matrine, curcumin, Ginsenoside Rh2, and so on. The aim of this paper is to provide new ideas for drug development to regulate JAK/STAT signaling for treating UC.

Mechanistic insights of diabetic wound: Healing process, associated pathways and microRNA-based delivery systems

Wounds that represent one of the most critical complications can occur in individuals suffering from diabetes mellitus, and results in the need for hospitalisation and, in severe cases, require amputation. This condition is primarily characterized by infections, persistent inflammation, and delayed healing processes, which exacerbate the overall health of the patients. As per the standard mechanism, signalling pathways such as PI3K/AKT, HIF-1, TGF-β, Notch, Wnt/β-Cat, NF-κB, JAK/STAT, TLR, and Nrf2 play major roles in inflammatory, proliferative and remodelling phases of wound healing. However, dysregulation of the above pathways has been seen during the healing of diabetic wounds. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate the expression of various genes and signalling pathways which are associated with the process of wound healing. In the past few years, there has been a great deal of interest in the potential of miRNAs as biological agents in the management of a number of disorders. These miRNAs have been shown to modulate expression of genes involved in the healing process of wounds. There have been previous reviews pertaining to clinical trials examining miRNAs in several disorders, but only a few clinical studies have examined involvement of miRNAs in healing of wounds. Considering the therapeutic promise, there are several obstacles concerning their instabilities and inefficient delivery into the target cells. Therefore, this review is an attempt to discuss precise roles of signalling pathways and miRNAs in different phases of wound healing, and their aberrant regulation in diabetic wounds, particularly. It has also compiled a range of delivery mechanisms as well as an overview of the latest findings pertaining to miRNAs and associated delivery systems for improved healing of diabetic wounds.

CD4+ T-Cell Lymphoma Harboring a Chimeric Antigen Receptor Integration in TP53

Malignant T-cell transformation after chimeric antigen receptor (CAR) T-cell therapy has been described, but the contribution of CAR integration to oncogenesis is not clear. Here we report a case of a T-cell lymphoma harboring a lentiviral integration in a known tumor suppressor, TP53, which developed in a patient with multiple myeloma after B-cell maturation antigen (BCMA) CAR T-cell therapy.

The role of natural products targeting macrophage polarization in sepsis-induced lung injury

Sepsis-induced acute lung injury (SALI) is characterized by a dysregulated inflammatory and immune response. As a key component of the innate immune system, macrophages play a vital role in SALI, in which a macrophage phenotype imbalance caused by an increase in M1 macrophages or a decrease in M2 macrophages is common. Despite significant advances in SALI research, effective drug therapies are still lacking. Therefore, the development of new treatments for SALI is urgently needed. An increasing number of studies suggest that natural products (NPs) can alleviate SALI by modulating macrophage polarization through various targets and pathways. This review examines the regulatory mechanisms of macrophage polarization and their involvement in the progression of SALI. It highlights how NPs mitigate macrophage imbalances to alleviate SALI, focusing on key signaling pathways such as PI3K/AKT, TLR4/NF-κB, JAK/STAT, IRF, HIF, NRF2, HMGB1, TREM2, PKM2, and exosome-mediated signaling. NPs influencing macrophage polarization are classified into five groups: terpenoids, polyphenols, alkaloids, flavonoids, and others. This work provides valuable insights into the therapeutic potential of NPs in targeting macrophage polarization to treat SALI.

The Ability of SOCS1 to Cross-Regulate GM-CSF Signaling is Dose Dependent

Suppressor of cytokine signaling (SOCS) 1 is a key negative regulator of interferon (IFN), interleukin (IL)12, and IL-2 family cytokine signaling through inhibition of the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway. To investigate the temporal induction of SOCS1 in response to cytokine in live cells and its selective regulation of signaling pathways, we generated a mouse expressing a Halo-tag-SOCS1 fusion protein (Halo-SOCS1) under control of the endogenous Socs1 promoter. Homozygous Halo-SOCS1 mice (Halo-Socs1KI/KI) were viable with minor T cell abnormalities, most likely due to enhanced Halo-SOCS1 expression in thymocytes compared with the untagged protein. IFNγ and IL-4 induced Halo-SOCS1 expression in macrophages derived from Halo-Socs1KI/KI mice, and a critical level of SOCS1 expression was required for inhibition of both IFNγ and granulocyte macrophage-colony stimulating factor (GM-CSF)-driven JAK-STAT signaling. In contrast, IFNγ priming to induce SOCS1 did not cross-regulate IL-4 signaling. This study indicates that while SOCS1 expression needs to exceed a critical threshold to inhibit IFNγ signaling, its selective regulation of cytokine signaling results from an as yet undetermined, level of regulatory control.

Design and functional studies of xylene-based cyclic mimetics of SOCS1 protein

Peptidomimetics of Suppressors of cytokine signaling 1 (SOCS1) protein demonstrated valid therapeutic potentials as anti-inflammatory agents. Indeed, SOCS1 has a small kinase inhibitory region (KIR) primarily involved in the inhibition of the JAnus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathway Herein, on the basis of previous investigations on a potent mimetic of KIR-SOCS1, named PS5, we designed and evaluated the SAR (Structure Activity Relationship) features of two xylene-based macrocycles analogues of PS5. These novel compounds bear thiol-xylene linkages with mono- and bi-cyclic scaffolds: they were in vitro functionally investigated toward JAK2 catalytic domain, as ligands with microscale thermophoresis (MST) and as inhibitors through LC-MS analyses. To evaluate structural properties Circular Dichroism (CD) and Nuclear Magnetic Resonance (NMR) spectroscopies were employed along with serum stability assays. Results indicated that a monocycle scaffold is well-tolerated by PS5 sequence enhancing the affinity toward the kinase with a KD in the low micromolar range and providing consistent inhibitory effects of the catalytic activity, which were evaluated for the first time in the case of SOCS1 mimetics. Conformationally, the presence of xylene scaffold affects the flexibility of the compounds and their stabilities to proteases degradation. This study contributes to the understanding of the factors necessary for accurately mimicking the inhibitory mechanism of SOCS1 protein towards JAK2 and to the translation of proteomimetics into drugs.

SOCS1 deficiency-crossroads of autoimmunity and autoinflammation-two case reports

Suppressors of cytokine signaling (SOCS) proteins play a critical role in regulating immune signaling pathways. Deficiency of SOCS1 leads to various autoimmune pathologies. We present two unrelated patients with distinct clinical manifestations. Patient 1, a 16-year-old male from Guinea, presented with Evans Syndrome, musculoskeletal pain and elevated liver enzymes. Patient 2, a 6-year-old German boy, developed recurrent oral aphthous ulcers, mild inflammatory bowel disease and chronic recurrent multifocal osteomyelitis. Both patients were diagnosed with SOCS1 deficiency by genetic testing. Treatment strategies included steroids, JAK inhibition and colchicine. These cases emphasize the importance of considering SOCS1 deficiency in patients with autoimmune or autoinflammatory diseases but also in patients with unexplained elevated IgE levels. They highlight the need for further research in ongoing multicenter registries to better understand this condition.

Investigation of the circulatory microRNAs and their involvement in regulation of inflammation in patients with COVID-19

BACKGROUND

Dysregulated levels of cytokines may lead to cytokine storm, which has been implicated in the immunopathogenesis of coronavirus disease 2019 (COVID-19). Here in the current study, the role of microRNA (miR)-155-5p, miR-146a, and miR-221-3p in the regulation of the immune responses and inflammatory state in patients with COVID-19 was investigated.

METHODS

In this case-control study, peripheral blood samples were obtained from 75 COVID-19 subjects and 100 healthy controls. From the plasma samples, RNA was extracted and cDNA was synthesized, and subsequently the transcript level of miRNAs was measured by Real-time PCR. The plasma levels of interleukin (IL)-4 and interferon (IFN)-γ were determined using ELISA.

RESULTS

miR-155-5p (fold change = 1.87, P = 0.020) and miR-221-3p (fold change = 2.26, P = 0.008), but not miR-146a, was upregulated in the plasma sample of COVID-19 cases compared to controls. The level of IFN-γ (but not IL-4) was significantly higher in the plasma samples of COVID-19 patients compared to control group. The expression level of miR-155-5p (r = 0.35, corrected P = 0.066) and miR-221-3p (r = 0.25, corrected P = 0.066) had positive correlation with the plasma levels of IFN-γ.

CONCLUSIONS

IFN-γ pathway in involved in the pathogenesis of COVID-19 that is regulated through miR-155-5p and miR-221-3p. These miRNAs showed potential utility as biomarkers for predicting the severity of COVID-19.

Manipulating immune activity of macrophages: a materials and mechanics perspective

Macrophage immune cells exist on a plastic spectrum of phenotypes governed by their physical and biochemical environment. Controlling macrophage function to facilitate immunological regeneration or fighting pathology has emerged as a therapeutic possibility. The rate-limiting step in translating macrophage immunomodulation therapies has been the absence of fundamental knowledge of how physics and biochemistry in the macrophage microenvironment converge to inform phenotype. In this review we explore recent trends in bioengineered model systems that integrate physical and biochemical variables applied to macrophage mechanosensing and plasticity. We focus on how tuning of mechanical forces and biomaterial composition orchestrate macrophage function in physiological and pathological contexts. Ultimately, a broader understanding of stimuli-responsiveness in macrophages leads to informed design for future modulatory therapies.

Borrelia burgdorferi sensu lato inhibits CIITA transcription through pSTAT3 activation and enhanced SOCS1 and SOCS3 expression leading to limited IFN-γ production

Interferons (IFNs) are important signaling molecules in the human immune response against micro-organisms. Throughout initial Borrelia burgdorferi sensu lato (B. burgdorferi s.l.) infection in vitro, inadequate IFN-γ production results in the absence of a strong T-helper 1 cell response, potentially hampering the development of an effective antibody responses in Lyme borreliosis (LB) patients. The aim of this study is to help understand the immunomodulatory mechanisms why IFN-γ production is absent in the early onset of LB. Therefore, cytokine production and STAT activation signature, following exposure of human immune cells to B. burgdorferi s.l., was investigated in vivo and in vitro. While STAT3 phosphorylation was highly induced in T cells, B cells and NK-(T) cells, STAT1 expression and IL-12p70 production were not or only slightly increased upon B. burgdorferi s.l. exposure. In response to B. burgdorferi s.l., STAT2 phosphorylation and IFNα production remained stable. STAT2 activation only increased in NK-(T) cells. In contrast, STAT4 signaling was reduced in all B. burgdorferi s.l. exposed immune cells. Moreover, B. burgdorferi s.l. significantly increased suppressor of cytokine signaling (SOCS)1 and SOCS3 gene expression in LB patients. Absence of IFN-γ production and STAT4 activation, in combination with STAT3 phosphorylation and upregulated SOCS1 and SOCS3 gene expression, suggests the formation of a more tolerant and anti-inflammatory response to B. burgdorferi s.l., specifically in T- and B-cells. In primary human PBMCs and monocyte populations, B. burgdorferi s.l. also specifically interfered with CIITA isoforms normally expressed in antigen presenting dendritic cells. In contrast, it enhanced CIITA isoforms typically present in adaptive immune cell subsets. Restoring antigen presentation capacity of innate immune cells and early production of IFN-γ in LB patients may help re-establish immune functions during initial LB. These new insights will help to understand the immunomodulatory mechanisms of B. burgdorferi s.l. during the onset of LB.

Entering a new era of tumor-infiltrating lymphocyte cell therapy innovation

The therapeutic potential of adoptive cell therapy using tumor-infiltrating lymphocytes (TIL) has been established in advanced melanoma. In February 2024, lifileucel became the first TIL cell therapy to be approved by the FDA and is indicated for adult patients with advanced melanoma. Although the benefit of TIL cell therapy is best characterized in patients with advanced melanoma, several trials are ongoing investigating its safety and efficacy in other solid tumor indications. Nevertheless, wider applicability and adoption of TIL cell therapy will require continued innovation to provide a safer and more efficacious cell therapy product. Several investigational TIL cell therapy products are in preclinical and early clinical development and are applying novel technologies to overcome key challenges. Herein, we summarize the current state of TIL cell therapy and highlight innovations that may reshape its future.

MicroRNAs as Prognostic Biomarkers for Atrial Fibrillation Recurrence After Catheter Ablation: Current Evidence and Future Directions

Atrial fibrillation (AF) is the most common cardiac arrhythmia encountered in clinical practice and is associated with significant morbidity and mortality. Even though catheter ablation has emerged as an available and effective treatment for AF, recurrence remains a significant challenge. This review presents the existing evidence on the prognostic role of microRNAs (miRNAs) in the prediction of AF recurrence after catheter ablation. We examined studies investigating the association between miRNA expression and post-ablation AF recurrence. Multiple miRNAs have been highlighted as potential biomarkers, which are involved in pathophysiological processes such as atrial remodeling, fibrosis, and inflammation. Despite some promising results, there has been significant heterogeneity across the studies. In this review, we demonstrate the potential miRNAs that can be routinely used as biomarkers of AF recurrence, and we identify areas that require further research to validate their clinical utility.

Interrelation of Natural Polyphenol and Fibrosis in Diabetic Nephropathy

Diabetic nephropathy (DN) is a common and serious complication of diabetes mellitus and a major cause of end-stage renal disease (ESRD). Renal fibrosis, which corresponds to excessive deposition of extracellular matrix and leads to scarring, is a characteristic feature of the various progressive stages of DN. It can trigger various pathological processes leading to the activation of autophagy, inflammatory responses and a vicious circle of oxidative stress and inflammation. Although it is known that DN can be alleviated by mechanisms linked to antioxidants, reducing inflammation and improving autophagy, how to improve DN by reducing fibrosis using natural polyphenols needs to be studied further. Nowadays, natural polyphenolic compounds with excellent safety and efficacy are playing an increasingly important role in drug discovery. Therefore, this review reveals the multiple mechanisms associated with fibrosis in DN, as well as the different signaling pathways (including TGF-β/SMAD, mTORC1/p70S6K, JAK/STAT/SOCS and Wnt/β-catenin) and the potential role in the fibrotic niche. In parallel, we summarize the types of polyphenolic compounds and their pharmacodynamic effects, and finally evaluate the use of polyphenols to modulate relevant targets and pathways, providing potential research directions for polyphenols to improve DN. In summary, the problem of long-term monotherapy resistance can be reduced with natural polyphenols, while reducing the incidence of toxic side effects. In addition, potential targets and their inhibitors can be identified through these pathways, offering potential avenues of research for natural polyphenols in the pharmacological treatment of multisite fibrosis.

Cullin-5 deficiency promotes chimeric antigen receptor T cell effector functions potentially via the modulation of JAK/STAT signaling pathway

Chimeric antigen receptor (CAR) T cell is a promising therapy for cancer, but factors that enhance the efficacy of CAR T cell remain elusive. Here we perform a genome-wide CRISPR screening to probe genes that regulate the proliferation and survival of CAR T cells following repetitive antigen stimulations. We find that genetic ablation of CUL5, encoding a core element of the multi-protein E3 ubiquitin-protein ligase complex, cullin-RING ligase 5, enhances human CD19 CAR T cell expansion potential and effector functions, potentially via the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway. In this regard, CUL5 knockout CD19 CAR T cells show sustained STAT3 and STAT5 phosphorylation, as well as delayed phosphorylation and degradation of JAK1 and JAK3. In vivo, shRNA-mediated knockdown of CUL5 enhances CD19 CAR T treatment outcomes in tumor-bearing mice. Our findings thus imply that targeting CUL5 in the ubiquitin system may enhance CAR T cell effector functions to enhance immunotherapy efficacy.

Primary Central Nervous System Lymphoma Tumor Biopsies Show Heterogeneity in Gene Expression Profiles, Genetic Subtypes, and in vitro Drug Sensitivity to Kinase Inhibitors

Primary central nervous system lymphoma (PCNSL) is clinically challenging due to its location and small biopsy size, leading to a lack of comprehensive molecular and biologic description. We previously demonstrated that 91% of PCNSL belong to the activated B-cell-like (ABC) molecular subtype of diffuse large B-cell lymphoma (DLBCL). Here we investigated the expression of 739 cancer related genes in HIV (-) patients using NanoString digital gene expression profiling in 25 ABC-PCNSL and 43 ABC-systemic DLBCL, all tumors were EBV (-). We found that two-thirds of ABC-PCNSL samples had a transcriptional landscape distinct from ABC-systemic DLBCL samples. Of the 739 genes measured, 135 were identified as differentially expressed between these ABC-PCNSL and ABC-systemic DLBCL (p<0.05). Compared with ABC-systemic DLBCL, ABC-PCNSL showed higher gene expression in several cancer related gene sets including genes related to Hedgehog, DNA damage repair, Wnt and MAPK signaling. Hierarchical clustering 28 PCNSL samples (25 ABC and 3 GCB subtypes) identified two transcriptional subgroups, P1 (n=9) and P2 (n=19). P2 showed higher activities across most of the cancer related pathways and had a significantly shorter patient survival time (p<0.01). Whole exome sequencing showed that some distinct genetic features of PCNSL compared to DLBCL. The genetic subtypes ("LymphGen") of PCNSL consisted mainly of "MCD" and "Other" subtypes, which did not correlate with clinical survival. These data provide more information about unique characters of PCNSL, which may help to identify novel drug targets for developing therapeutic strategies.

Unravelling the druggability and immunological roles of the SOCS-family proteins

The Suppressor of Cytokine Signalling (SOCS) protein family play a critical role in cytokine signalling and regulation of the JAK/STAT pathway with functional consequences to the immune response. Members of this family are implicated in multiple different signalling cascades that drive autoimmune diseases and cancer, through their binding to phosphotyrosine modified proteins as well as ubiquitination activity as part of Cullin5 RING E3 ligases. Here we review the SOCS family members CISH and SOCS1-SOCS7, with a focus on their complex role in immunity. The interactome and signalling network of this protein family is discussed, and the intricate mechanisms through which SOCS proteins alter and manage the immune system are assessed. We offer structural insights into how SOCS proteins engage their interacting partners and native substrates at the protein-protein interaction level. We describe how this knowledge has enabled drug discovery efforts on SOCS proteins to date and propose strategies for therapeutic intervention using small molecules, either via direct inhibition or leveraging their E3 ligase activity for targeted protein degradation.

Overview of hepatocarcinogenesis focusing on cellular origins of liver cancer stem cells: a narrative review

Hepatocellular carcinoma (HCC) accounts for 85% to 90% of primary liver cancers and generally has a poor prognosis. The hierarchical model, which posits that HCC originates from liver cancer stem cells (CSCs), is now widely accepted, as it is for other cancer types. As CSCs typically reside in the G0 phase of the cell cycle, they are resistant to conventional chemotherapy. Therefore, to effectively treat HCC, developing therapeutic strategies that target liver CSCs is essential. Clinically, HCCs exhibit a broad spectrum of pathological and clinical characteristics, ranging from well-differentiated to poorly differentiated forms, and from slow-growing tumors to aggressive ones with significant metastatic potential. Some patients with HCC also show features of cholangiocarcinoma. This HCC heterogeneity may arise from the diverse cellular origins of liver CSCs. This review explores the normal physiology of liver regeneration and provides a comprehensive overview of hepatocarcinogenesis, including cancer initiation, isolation of liver CSCs, molecular signaling pathways, and microRNAs. Additionally, the cellular origins of liver CSCs are reviewed, emphasizing hematopoietic and mesenchymal stem cells, along with the well-known hepatocytes and hepatic progenitor cells.

STATs, promising targets for the treatment of autoimmune and inflammatory diseases

Cytokines play a crucial role in the pathophysiology of autoimmune and inflammatory diseases, with over 50 cytokines undergoing signal transduction through the Signal Transducers and Activators of Transcription (STAT) signaling pathway. Recent studies have solidly confirmed the pivotal role of STATs in autoimmune and inflammatory diseases. Therefore, this review provides a detailed summary of the immunological functions of STATs, focusing on exploring their mechanisms in various autoimmune and inflammatory diseases. Additionally, with the rapid advancement of structural biology in the field of drug discovery, many STAT inhibitors have been identified using structure-based drug design strategies. In this review, we also examine the structures of STAT proteins and compile the latest research on STAT inhibitors currently being tested in animal models and clinical trials for the treatment of immunological diseases, which emphasizes the feasibility of STATs as promising therapeutic targets and provides insights into the design of the next generation of STAT inhibitors.

IL-4 Downregulates PD-L1 Level Via SOCS1 Upregulation-Induced JNK Deactivation to Enhance Antitumor Immunity in In Vitro Colorectal Cancer

Interleukin-4 (IL-4) controls cell growth and immune system regulation in tumorigenesis and can inhibit the growth of colon cancer cell lines, but the possible mechanism is unclear. In this study, we investigated the possible mechanism of IL-4 in colorectal cancer (CRC) through in vitro experiments. CRC cells received treatment with IL-4 (50 ng/mL), investigating the suppressor of cytokine signaling 1 (SOCS1)-related mechanism underlying the role of IL-4 in the progression and immunosuppression of CRC. The malignant processes of CRC cells and CD8+T cell-mediated immune response in CRC cells were determined by CCK-8, Transwell, wound healing, and flow cytometry assays. Programmed death ligand 1 (PD-L1), SOCS1 expressions, and c-Jun N-terminal kinase (JNK) activation in CRC cells were analyzed by quantitative reverse transcription polymerase chain reaction and/or Western blot. IL-4 repressed the malignant processes, yet promoted the apoptosis of CRC cells. Besides, IL-4 downregulated PD-L1 level, upregulated SOCS1 level, and restrained JNK activation in CRC cells, while enhancing CRC cell-killing effect of CD8+T cells. IL-4-induced effects on the aforementioned malignant processes of CRC cells and the killing effect of CD8+T cells toward CRC cells were all reversed when SOCS1 was knocked down in the CRC cells. IL-4 downregulates PD-L1 level via SOCS1 upregulation-induced JNK deactivation to enhance antitumor immunity in in vitro CRC. The study provides a theoretical basis for the clinical application of IL-4 in antitumor immunity in CRC.

Dynamic Interplay of Loop Motions Governs the Molecular Level Regulatory Dynamics in Spleen Tyrosine Kinase: Insights from Molecular Dynamics Simulations

The spleen tyrosine kinase (Syk) is a key regulator in immune cell signaling and is linked to various mechanisms in cancer and neurodegenerative diseases. Although most computational research on Syk focuses on novel drug design, the molecular-level regulatory dynamics remain unexplored. In this study, we utilized 5 × 1 μs all-atom molecular dynamics simulations of the Syk kinase domain, examining it in combinations of activation segment phosphorylated/unphosphorylated (at Tyr525, Tyr526) and the "DFG"-Asp protonated/deprotonated (at Asp512) states to investigate conformational variations and regulatory dynamics of various loops and motifs within the kinase domain. Our findings revealed that the formation and disruption of several electrostatic interactions among residues within and near the activation segment likely influenced its dynamics. The protein structure network analysis indicated that the N-terminal and C-terminal anchors were stabilized by connections with the nearby stable helical regions. The P-loop showed conformational variation characterized by movements toward and away from the conserved "HRD"-motif. Additionally, there was a significant correlation between the movement of the β3-αC loop and the P-loop, which controls the dimensions of the adenine-binding cavity of the C-spine region. Overall, understanding these significant motions of the Syk kinase domain enhances our knowledge of its functional regulatory mechanism and can guide future research.

Identification and Ranking of Binding Sites from Structural Ensembles: Application to SARS-CoV-2

Target identification and evaluation is a critical step in the drug discovery process. Although time-intensive and complex, the challenge becomes even more acute in the realm of infectious disease, where the rapid emergence of new viruses, the swift mutation of existing targets, and partial effectiveness of approved antivirals can lead to outbreaks of significant public health concern. The COVID-19 pandemic, caused by the SARS-CoV-2 virus, serves as a prime example of this, where despite the allocation of substantial resources, Paxlovid is currently the only effective treatment. In that case, significant effort pre-pandemic had been expended to evaluate the biological target for the closely related SARS-CoV. In this work, we utilize the computational hot spot mapping method, FTMove, to rapidly identify and rank binding sites for a set of nine SARS-CoV-2 drug/potential drug targets. FTMove takes into account protein flexibility by mapping binding site hot spots across an ensemble of structures for a given target. To assess the applicability of the FTMove approach to a wide range of drug targets for viral pathogens, we also carry out a comprehensive review of the known SARS-CoV-2 ligandable sites. The approach is able to identify the vast majority of all known sites and a few additional sites, which may in fact be yet to be discovered as ligandable. Furthermore, a UMAP analysis of the FTMove features for each identified binding site is largely able to separate predicted sites with experimentally known binders from those without known binders. These results demonstrate the utility of FTMove to rapidly identify actionable sites across a range of targets for a given indication. As such, the approach is expected to be particularly useful for assessing target binding sites for any emerging pathogen, as well as for indications in other disease areas, and providing actionable starting points for structure-based drug design efforts.

Unveiling the pathological functions of SOCS in colorectal cancer: Current concepts and future perspectives

Colorectal cancer (CRC) remains a significant global health challenge, marked by increasing incidence and mortality rates in recent years. The pathogenesis of CRC is complex, involving chronic inflammation of the intestinal mucosa, heightened immunoinflammatory responses, and resistance to apoptosis. The suppressor of cytokine signaling (SOCS) family, comprised of key negative regulators within cytokine signaling pathways, plays a crucial role in cell proliferation, growth, and metabolic regulation. Deficiencies in various SOCS proteins can trigger the activation of the Janus kinase (JAK) and signal transducers and activators of transcription (STAT) pathways, following the binding of cytokines and growth factors to their receptors. Mounting evidence indicates that SOCS proteins are integral to the development and progression of CRC, positioning them as promising targets for novel anticancer therapies. This review delves into the structure, function, and molecular mechanisms of SOCS family members, examining their roles in cell proliferation, apoptosis, migration, epithelial-mesenchymal transition (EMT), and immune modulation. Additionally, it explores their potential impact on the regulation of CRC immunotherapy, offering new insights and perspectives that may inform the development of innovative therapeutic strategies for CRC.

Transcriptional control of interferon-stimulated genes

Interferon-induced genes are among the best-studied groups of coregulated genes. Nevertheless, intense research into their regulation, supported by new technologies, is continuing to provide insights into their many layers of transcriptional regulation and to reveal how cellular transcriptomes change with pathogen-induced innate and adaptive immunity. This article gives an overview of recent findings on interferon-induced gene regulation, paying attention to contributions beyond the canonical JAK-STAT pathways.

Refractory Celiac Disease: What the Gastroenterologist Should Know

Fewer than 1% of patients with celiac disease (CD) will develop refractory CD (RCD). As such, most gastroenterologists might never need to manage patients with RCD. However, all gastroenterologists must be familiarized with the basic concepts of RCD and non-responsive CD (NRCD), since it can present as a severe disease with high mortality, not only due to intestinal failure, but also due to progression to enteropathy-associated T cell lymphoma (EATL) and a higher susceptibility to life-threatening infections. The diagnostic workup and differential diagnosis with other causes of gastrointestinal symptoms and villous atrophy, as well as the differentiation between type I and II RCD, are complex, and may require specialized laboratories and reference hospitals. Immunosuppression is efficient in the milder RCDI; however, the treatment of RCDII falls short, with current options probably only providing transient clinical improvement and delaying EATL development. This review summarizes the current diagnostic and therapeutic approach for patients with RCD that all doctors that manage patients with CD should know.

The 5'UTR of porcine reproductive and respiratory syndrome virus strain JXwn06 harbors a uORF that regulates cellular inflammation

The 5' untranslated region (5'UTR) of many positive-stranded RNA viruses contain functional regulatory sequences. Here, we show that the porcine reproductive and respiratory syndrome virus (PRRSV), a member of arteriviruses, harbors small upstream open reading frames (uORFs) in its 5'UTR. Bioinformatics analysis shows that this feature is relatively well conserved among PRRSV strains and Arteriviridae. We also identified a uORF, namely uORF2, in the PRRSV strain JXwn06, that possesses translational activity and exerts a suppressive effect on the expression of the primary ORF evidenced by in vitro reporter assays. We tested its importance via reverse genetics by introducing a point mutation into the PRRSV infectious cDNA clone to inactivate the start codon of uORF2. The recovered mutant virus Mut2 surprisingly replicated to the same level as the wild-type virus (WT), but induced a higher level of inflammatory cytokines (e.g., TNF-α, IL-1β, and IL-6) both in vitro and in animal experiments, correlating well with more severe lung injury and higher death rate. In line with this, over-expression of uORF2 in transfected cells significantly inhibited poly(I:C)-induced expression of inflammatory cytokines. Together, our data support the idea that uORF2 encodes a novel, functional regulator of PRRSV virulence despite of its short size.

IMPORTANCE

PRRSV has remained a major challenge to the world swine industry, but we still do not know much about its biology and pathogenesis. Here, we provide evidence to show that the 5'UTR of PRRSV strain JXwn06 harbors a functional uORF that has the coding capacity and regulates induction of inflammation as demonstrated by in vitro assays and animal experiment. The findings reveal a novel viral factor that regulates cellular inflammation and provide insight into the understanding of PRRSV pathogenesis.

IL23R mutations associated with decreased risk of psoriasis lead to the differential expression of genes implicated in the disease

Psoriasis is an incurable immune-mediated skin disease, affecting around 1%-3% of the population. Various lines of evidence implicate IL23 as being pivotal in disease. Genetic variants within the IL23 receptor (IL23R) increase the risk of developing psoriasis, and biologic therapies specifically targeting IL23 demonstrated high efficacy in treating disease. IL23 acts via the IL23R, signalling through the STAT3 pathway, mediating the cascade of events that ultimately results in the clinical presentation of psoriasis. Given the essential role of IL23R in disease, it is important to understand the impact of genetic variants on receptor function with respect to downstream gene regulation. Here we developed model systems in CD4+ (Jurkat) and CD8+ (MyLa) T cells to express either the wild type risk or mutant (R381Q) protective form of IL23R. After confirmation that the model system expressed the genes/proteins and had a differential effect on the phosphorylation of STAT3, we used RNAseq to explore differential gene regulation, in particular for genes implicated with risk to psoriasis, at a single time point for both cell types, and in a time course experiment for Jurkat CD4+ T cells. These experiments discovered differentially regulated genes in the cells expressing wild type and mutant IL23R, including HLA-B, SOCS1, RUNX3, CCR5, CXCR3, CCR9, KLF3, CD28, IRF, SOCS6, TNFAIP and ICAM5, that have been implicated in both the IL23 pathway and psoriasis. These genes have the potential to define a IL23/psoriasis pathway in disease, advancing our understanding of the biology behind the disease.

Targeting Nuclear Receptor Coactivator SRC-1 Prevents Colorectal Cancer Immune Escape by Reducing Transcription and Protein Stability of PD-L1

Programmed death-ligand 1 (PD-L1) is overexpressed in multiple cancers and critical for their immune escape. It has previously shown that the nuclear coactivator SRC-1 promoted colorectal cancer (CRC) progression by enhancing CRC cell viability, yet its role in CRC immune escape is unclear. Here, we demonstrate that SRC-1 is positively correlated with PD-L1 in human CRC specimens. SRC-1 deficiency significantly inhibits PD-L1 expression in CRC cells and retards murine CRC growth in subcutaneous grafts by enhancing CRC immune escape via increasing tumor infiltration of CD8+ T cells. Genetic ablation of SRC-1 in mice also decreases PD-L1 expression in AOM/DSS-induced murine CRC. These results suggest that tumor-derived SRC-1 promotes CRC immune escape by enhancing PD-L1 expression. Mechanistically, SRC-1 activated JAK-STAT signaling by inhibiting SOCS1 expression and coactivated STAT3 and IRF1 to enhance PD-L1 transcription as well as stabilized PD-L1 protein by inhibiting proteasome-dependent degradation mediated by speckle type POZ protein (SPOP). Pharmacological inhibition of SRC-1 improved the antitumor effect of PD-L1 antibody in both subcutaneous graft and AOM/DSS-induced murine CRC models. Taken together, these findings highlight a crucial role of SRC-1 in regulating PD-L1 expression and targeting SRC-1 in combination with PD-L1 antibody immunotherapy may be an attractive strategy for CRC treatment.

Tetrastigma hemsleyanum polysaccharide ameliorated ulcerative colitis by remodeling intestinal mucosal barrier function via regulating the SOCS1/JAK2/STAT3 pathway

Ulcerative colitis (UC) is characterized by a chronic and protracted course and often leads to a poor prognosis. Patients with this condition often experience postoperative complications, further complicating the management of their condition. Tetrastigma hemsleyanum polysaccharide (THP) has demonstrated considerable potential as a treatment for inflammatory bowel disease. However, its underlying mechanism in the treatment of UC remains unclear. This study systematically and comprehensively investigated the effects of THP on dextran sulfate-induced UC mice and illustrated its specific mechanism of action. The colon and spleen in UC mice were restored after THP treatment. The levels of key markers, such as secretory immunoglobulin A, β-defensin, and mucin-2 were increased, collagen deposition and epithelial cell apoptosis were decreased. Notably, THP administration led to increased levels of Ki67 and tight junction proteins in colon tissue and reduced colon tissue permeability. THP contributed to the restored balance of intestinal flora. Furthermore, THP downregulated the expressions of the proinflammatory cytokines interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-17 and promoted those of the regulatory factors forkhead box protein P3. It also exerted anti-inflammatory effects by promoting suppressor of cytokine signaling (SOCS1) expression and inhibiting the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Our results demonstrated that THP had an efficacy comparable to that of JAK inhibitor in treating UC. In addition, THP might play a role in UC therapy through modulation of the SOCS1/JAK2/STAT3 signaling pathway and remodeling of the intestinal mucosal barrier.

TRIM8 as a predictor for prognosis in childhood acute lymphoblastic leukemia based on a signature of neutrophil extracellular traps

Background

Neutrophil extracellular traps (NETs) can be attributed to the metastasis, occurrence, and immune evasion of cancer cells. We investigated the prognostic value of NET-related genes in childhood acute lymphoblastic leukemia (cALL) patients.

Methods

Differential gene expression analysis was conducted on samples collected from public databases. Grouping them based on the expression level of NET-related genes, we assessed the correlation between immune cell types and the risk score for having a poor prognosis of cALL, with an evaluation of the sensitivity of drugs used in cALL. We further divided the groups, integrating survival data. Subsequently, methods including multivariable Cox algorithms, least absolute shrinkage and selection operator (LASSO), and univariable were utilized to create a risk model predicting prognosis. Experiments in cell lines and animals were performed to explore the functions of TRIM8, a gene selected by the model. To validate the role of TRIM8 in leukemia development, lentivirus-mediated overexpression or knockdown of TRIM8 was employed in mice with T-ALL and B-ALL.

Results

Kaplan-Meier (KM) analysis underscored the importance of differentially expressed genes identified in the groups divided by genes participated in NETs, with enrichment analysis showing the mechanism. Correlation analysis revealed significant associations with B cells, NK cells, mast cells, T cells, plasma cells, dendritic cells, and monocytes. The IC50 values of drugs such as all-trans-retinoic acid (ATRA), axitinib, doxorubicin, methotrexate, sorafenib, and vinblastine were increased, while dasatinib exhibited a lower IC50. A total of 13 NET-related genes were selected in constructing the risk model. In the training, testing, and merged cohorts, KM analysis demonstrated significantly improved survival for low-risk cALL patients compared to high-risk cALL patients (p < 0.001). The area under the curve (AUC) indicated strong predictive performance. Experiments in Jurkat and SUP-B15 revealed that TRIM8 knockdown decreased the proliferation of leukemia cell lines. Further experiments demonstrated a more favorable prognosis in mice with TRIM8-knockdown leukemia cells. Results of cell lines and animals showed better outcomes in prognosis when TRIM8 was knocked down.

Conclusion

We identified a novelty in a prognostic model that could aid in the development of personalized treatments for cALL patients. Furthermore, it revealed that the expression of TRIM8 is a contributing factor to the proliferation of leukemia cells and worsens the prognosis of cALL.