Kinase inhibition, competitive binding and proteasomal degradation: resolving the molecular function of the suppressor of cytokine signaling (SOCS) proteins

Genome-wide identification of socs gene in rainbow trout (Oncorhynchus mykiss) and response to microplastic exposure

BACKGROUND

To investigate the response of the suppressor of the cytokine signaling (socs) gene family in rainbow trout following exposure to microplastics, this study conducted a bioinformatics analysis of the socs gene family using rainbow trout genome data, complemented by experiments involving microplastic exposure and gene expression detection.

METHODS AND RESULTS

The findings revealed that the rainbow trout SOCS gene family comprises 27 members, encoding proteins with lengths ranging from 110 to 837 amino acids. Analyses of motifs, domains, and gene structures indicate that members of this family are highly conserved. RNA sequencing data demonstrated that, following microplastic exposure, the expression levels of socs1, socs2, socs3, socs5, socs6, socs7, and cish in the liver, intestine, and brain tissues of rainbow trout underwent significant changes. Additionally, RT-qPCR results indicated that the expression levels of several socs genes were down-regulated, whereas socs1a, socs1b, socs7a1, socs7b1, and socs7b2 exhibited significant up-regulation. These genes may play crucial roles in the response to microplastic exposure in rainbow trout.

CONCLUSION

This study elucidates the involvement of the socs gene family members in the context of microplastic exposure, providing valuable insights into the underlying toxicological mechanisms and enhancing our understanding of the threats posed by plastic pollution to freshwater organisms.

Emerging concepts and treatments in autoinflammatory interferonopathies and monogenic systemic lupus erythematosus

Over the past two decades, the number of genetically defined autoinflammatory interferonopathies has steadily increased. Aicardi-Goutières syndrome and proteasome-associated autoinflammatory syndromes (PRAAS, also known as CANDLE) are caused by genetic defects that impair homeostatic intracellular nucleic acid and protein processing respectively. Research into these genetic defects revealed intracellular sensors that activate type I interferon production. In SAVI and COPA syndrome, genetic defects that cause chronic activation of the dinucleotide sensor stimulator of interferon genes (STING) share features of lung inflammation and fibrosis; and selected mutations that amplify interferon-α/β receptor signalling cause central nervous system manifestations resembling Aicardi-Goutières syndrome. Research into the monogenic causes of childhood-onset systemic lupus erythematosus (SLE) demonstrates the pathogenic role of autoantibodies to particle-bound extracellular nucleic acids that distinguishes monogenic SLE from the autoinflammatory interferonopathies. This Review introduces a classification for autoinflammatory interferonopathies and discusses the divergent and shared pathomechanisms of interferon production and signalling in these diseases. Early success with drugs that block type I interferon signalling, new insights into the roles of cytoplasmic DNA or RNA sensors, pathways in type I interferon production and organ-specific pathology of the autoinflammatory interferonopathies and monogenic SLE, reveal novel drug targets that could personalize treatment approaches.

Zebrafish Suppressor of Cytokine Signaling 4b (Socs4b) Is Dispensable for Development but May Regulate Epidermal Growth Factor Receptor Signaling

The suppressor of cytokine signaling (SOCS) family of proteins were named after their defining role as negative feedback regulators of signaling initiated by numerous cytokine receptors. However, multiple members of the SOCS family likely function outside of this paradigm, including SOCS4. Zebrafish possess two SOCS4 paralogues, with socs4a previously shown to participate in central nervous system development and function. This study examined the role of the other paralogue, socs4b, through expression analysis and functional investigations in vivo and in vitro. This revealed maternal deposition of socs4b mRNA, specific zygotic expression during late embryogenesis, including in the brain, eye and intestine, and broad adult expression that was highest in the brain. A mutant allele, socs4bΔ18, was generated by genome editing, in which the start codon was deleted. Fish homozygous for this likely hypomorphic allele showed no overt developmental phenotypes. However, in vitro studies suggested the Socs4b protein may be able to regulate EGFR signaling.

Irradiated engineered tumor cell-derived microparticles remodel the tumor immune microenvironment and enhance antitumor immunity

Radiotherapy (RT), administered to roughly half of all cancer patients, occupies a crucial role in the landscape of cancer treatment. However, expanding the clinical indications of RT remains challenging. Inspired by the radiation-induced bystander effect (RIBE), we used the mediators of RIBE to mimic RT. Specifically, we discovered that irradiated tumor cell-released microparticles (RT-MPs) mediated the RIBE and had immune activation effects. To further boost the immune activation effect of RT-MPs to achieve cancer remission, even in advanced stages, we engineered RT-MPs with different cytokine and chemokine combinations by modifying their production method. After comparing the therapeutic effect of the engineered RT-MPs in vitro and in vivo, we demonstrated that tIL-15/tCCL19-RT-MPs effectively activated antitumor immune responses, significantly prolonged the survival of mice with malignant pleural effusion (MPE), and even achieved complete cancer remission. When tIL-15/tCCL19-RT-MPs were combined with PD-1 monoclonal antibody (mAb), a cure rate of up to 60% was achieved. This combination therapy relied on the activation of CD8+ T cells and macrophages, resulting in the inhibition of tumor growth and the establishment of immunological memory against tumor cells. Hence, our research may provide an alternative and promising strategy for cancers that are not amenable to conventional RT.

Lung cancer treatment potential and limits associated with the STAT family of transcription factors

Lung cancer is one of the mortal cancers and the leading cause of cancer-related mortality, with a cancer survival rate of fewer than 5% in developing nations. This low survival rate can be linked to things like late-stage detection, quick postoperative recurrences in patients receiving therapy, and chemoresistance developing against various lung cancer treatments. Signal transducer and activator of transcription (STAT) family of transcription factors are involved in lung cancer cell proliferation, metastasis, immunological control, and treatment resistance. By interacting with specific DNA sequences, STAT proteins trigger the production of particular genes, which in turn result in adaptive and incredibly specific biological responses. In the human genome, seven STAT proteins have been discovered (STAT1 to STAT6, including STAT5a and STAT5b). Many external signaling proteins can activate unphosphorylated STATs (uSTATs), which are found inactively in the cytoplasm. When STAT proteins are activated, they can increase the transcription of several target genes, which leads to unchecked cellular proliferation, anti-apoptotic reactions, and angiogenesis. The effects of STAT transcription factors on lung cancer are variable; some are either pro- or anti-tumorigenic, while others maintain dual, context-dependent activities. Here, we give a succinct summary of the various functions that each member of the STAT family plays in lung cancer and go into more detail about the advantages and disadvantages of pharmacologically targeting STAT proteins and their upstream activators in the context of lung cancer treatment.

The interweaved signatures of common-gamma-chain cytokines across immunologic lineages

"γc" cytokines are a family whose receptors share a "common-gamma-chain" signaling moiety, and play central roles in differentiation, homeostasis, and communications of all immunocyte lineages. As a resource to better understand their range and specificity of action, we profiled by RNAseq the immediate-early responses to the main γc cytokines across all immunocyte lineages. The results reveal an unprecedented landscape: broader, with extensive overlap between cytokines (one cytokine doing in one cell what another does elsewhere) and essentially no effects unique to any one cytokine. Responses include a major downregulation component and a broad Myc-controlled resetting of biosynthetic and metabolic pathways. Various mechanisms appear involved: fast transcriptional activation, chromatin remodeling, and mRNA destabilization. Other surprises were uncovered: IL2 effects in mast cells, shifts between follicular and marginal zone B cells, paradoxical and cell-specific cross-talk between interferon and γc signatures, or an NKT-like program induced by IL21 in CD8+ T cells.

The Vicious Cycle of Melanoma-Microglia Crosstalk: Inter-Melanoma Variations in the Brain-Metastasis-Promoting IL-6/JAK/STAT3 Signaling Pathway

Previous studies from our lab demonstrated that the crosstalk between brain-metastasizing melanoma cells and microglia, the macrophage-like cells of the central nervous system, fuels progression to metastasis. In the present study, an in-depth investigation of melanoma-microglia interactions elucidated a pro-metastatic molecular mechanism that drives a vicious melanoma-brain-metastasis cycle. We employed RNA-Sequencing, HTG miRNA whole transcriptome assay, and reverse phase protein arrays (RPPA) to analyze the impact of melanoma-microglia interactions on sustainability and progression of four different human brain-metastasizing melanoma cell lines. Microglia cells exposed to melanoma-derived IL-6 exhibited upregulated levels of STAT3 phosphorylation and SOCS3 expression, which, in turn, promoted melanoma cell viability and metastatic potential. IL-6/STAT3 pathway inhibitors diminished the pro-metastatic functions of microglia and reduced melanoma progression. SOCS3 overexpression in microglia cells evoked microglial support in melanoma brain metastasis by increasing melanoma cell migration and proliferation. Different melanomas exhibited heterogeneity in their microglia-activating capacity as well as in their response to microglia-derived signals. In spite of this reality and based on the results of the present study, we concluded that the activation of the IL-6/STAT3/SOCS3 pathway in microglia is a major mechanism by which reciprocal melanoma-microglia signaling engineers the interacting microglia to reinforce the progression of melanoma brain metastasis. This mechanism may operate differently in different melanomas.

Advances in the potential roles of Cullin-RING ligases in regulating autoimmune diseases

Cullin-RING ligases (CRLs) are the largest class of E3 ubiquitin ligases regulating the stability and subsequent activity of a large number of important proteins responsible for the development and progression of various diseases, including autoimmune diseases (AIDs). However, the detailed mechanisms of the pathogenesis of AIDs are complicated and involve multiple signaling pathways. An in-depth understanding of the underlying regulatory mechanisms of the initiation and progression of AIDs will aid in the development of effective therapeutic strategies. CRLs play critical roles in regulating AIDs, partially by affecting the key inflammation-associated pathways such as NF-κB, JAK/STAT, and TGF-β. In this review, we summarize and discuss the potential roles of CRLs in the inflammatory signaling pathways and pathogenesis of AIDs. Furthermore, advances in the development of novel therapeutic strategies for AIDs through targeting CRLs are also highlighted.

Molecular and clinical diversity in primary central nervous system lymphoma

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a rare and distinct entity within diffuse large B-cell lymphoma presenting with variable response rates probably to underlying molecular heterogeneity.

PATIENTS AND METHODS

To identify and characterize PCNSL heterogeneity and facilitate clinical translation, we carried out a comprehensive multi-omic analysis [whole-exome sequencing, RNA sequencing (RNA-seq), methylation sequencing, and clinical features] in a discovery cohort of 147 fresh-frozen (FF) immunocompetent PCNSLs and a validation cohort of formalin-fixed, paraffin-embedded (FFPE) 93 PCNSLs with RNA-seq and clinico-radiological data.

RESULTS

Consensus clustering of multi-omic data uncovered concordant classification of four robust, non-overlapping, prognostically significant clusters (CS). The CS1 and CS2 groups presented an immune-cold hypermethylated profile but a distinct clinical behavior. The 'immune-hot' CS4 group, enriched with mutations increasing the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) and nuclear factor-κB activity, had the most favorable clinical outcome, while the heterogeneous-immune CS3 group had the worse prognosis probably due to its association with meningeal infiltration and enriched HIST1H1E mutations. CS1 was characterized by high Polycomb repressive complex 2 activity and CDKN2A/B loss leading to higher proliferation activity. Integrated analysis on proposed targets suggests potential use of immune checkpoint inhibitors/JAK1 inhibitors for CS4, cyclin D-Cdk4,6 plus phosphoinositide 3-kinase (PI3K) inhibitors for CS1, lenalidomide/demethylating drugs for CS2, and enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) inhibitors for CS3. We developed an algorithm to identify the PCNSL subtypes using RNA-seq data from either FFPE or FF tissue.

CONCLUSIONS

The integration of genome-wide data from multi-omic data revealed four molecular patterns in PCNSL with a distinctive prognostic impact that provides a basis for future clinical stratification and subtype-based targeted interventions.

Genome-wide identification of olive flounder (Paralichthys olivaceus) SOCS genes: Involvement in immune response regulation to temperature stress and Edwardsiella tarda infection

The suppressors of cytokine signaling (SOCS) gene family participates in development and immunity through negative regulation of cytokine signaling pathways. Although the immune response of SOCS gene family members has been extensively characterized in teleost, no similar study has been reported in olive flounder yet. In our present study, a total of 13 SOCSs in olive flounder were identified and characterized systematically. By querying the SOCS sequences of ten teleost fish species, we found there were exactly more members of SOCSs in fish than mammals, which indicated that there were more duplication events occurred in fish than in higher vertebrates. Phylogenetic analysis clearly illuminated that SOCS genes were highly conserved. The analysis of gene structure and motif showed SOCS proteins of olive flounder shared a high level of sequence similarity strikingly. The expression profiles of tissues and developmental stages indicated that SOCS members had a kind of specificity in temporality and spatiality. RNA-Seq analysis of temperature stress and E. Tarda infection demonstrated SOCS members were involved in inflammatory response. In a word, our results would provide a further reference for understanding the mechanism of SOCS genes in olive flounder.

The JAK-STAT pathway at 30: Much learned, much more to do

The discovery of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway arose from investigations of how cells respond to interferons (IFNs), revealing a paradigm in cell signaling conserved from slime molds to mammals. These discoveries revealed mechanisms underlying rapid gene expression mediated by a wide variety of extracellular polypeptides including cytokines, interleukins, and related factors. This knowledge has provided numerous insights into human disease, from immune deficiencies to cancer, and was rapidly translated to new drugs for autoimmune, allergic, and infectious diseases, including COVID-19. Despite these advances, major challenges and opportunities remain.

Digesting the Role of JAK-STAT and Cytokine Signaling in Oral and Gastric Cancers

When small proteins such as cytokines bind to their associated receptors on the plasma membrane, they can activate multiple internal signaling cascades allowing information from one cell to affect another. Frequently the signaling cascade leads to a change in gene expression that can affect cell functions such as proliferation, differentiation and homeostasis. The Janus kinase-signal transducer and activator of transcription (JAK-STAT) and the tumor necrosis factor receptor (TNFR) are the pivotal mechanisms employed for such communication. When deregulated, the JAK-STAT and the TNF receptor signaling pathways can induce chronic inflammatory phenotypes by promoting more cytokine production. Furthermore, these signaling pathways can promote replication, survival and metastasis of cancer cells. This review will summarize the essentials of the JAK/STAT and TNF signaling pathways and their regulation and the molecular mechanisms that lead to the dysregulation of the JAK-STAT pathway. The consequences of dysregulation, as ascertained from founding work in haematopoietic malignancies to more recent research in solid oral-gastrointestinal cancers, will also be discussed. Finally, this review will highlight the development and future of therapeutic applications which modulate the JAK-STAT or the TNF signaling pathways in cancers.

Electromagnetic Fields Change the Expression of Suppressor of Cytokine Signaling 3 (SOCS3) and Cathepsin L2 (CTSL2) Genes in Adenocarcinoma Gastric (AGS) Cell Line

Background: Gastric cancer is one of the most prevalent and deadliest cancers in the world. Environmental factors including chemicals, sunlight, and electromagnetic fields can induce changes in gene expression. Though the resizing mechanism of its effect has not been fully recognized, free radicals are seen as the possible mechanism involved. Although low-frequency electromagnetic fields are not considered a carcinogenic factor, some studies have shown disruption in deoxyribonucleic acid (DNA) and gene expression in different cell categories. Objectives: This study was intendant to examine the effects of low-frequency electromagnetic flux densities of 0.2 and 2 mT on the expression of cathepsin L2 (CTSL2) and suppressor of cytokine signaling 3 (SOCS3) genes in adenocarcinoma gastric (AGS) cell lines. Methods: The AGS cell line was cultured in Hamas12 and was exposed to electromagnetic fields continuously and discontinuously for 18 hours. Moreover, Cell viability was assessed by the MTT (3-(4, 5-Dimethylthiazol-2-yl)) assay. The change in the expression of genes was measured by real-time polymerase chain reaction (PCR). Results: Low-frequency electromagnetic fields increased gene expression compared to the control group. The changes in the expression are directly associated with the electromagnetic field strength. Expression levels of CTSL2 were increased under the exposure of electromagnetic fields and this increase was significant when discontinuous exposure was applied (33.26 ± 7.4 fold change for 0.2mT and 64.4 ± 7.7 for 2mT, p- value

Molecular characterization and immunoregulatory analysis of suppressors of cytokine signaling 1 (SOCS1) in black rockfish, Sebastes schlegeli

The suppressors of cytokine signaling (SOCS) family are important soluble mediators to inhibit signal transduction via the Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway in the innate and adaptive immune responses. SOCS1 is the primary regulator of a number of cytokines. In this study, two spliced transcripts of SOCS1 were identified and characterized from black rockfish (Sebastes schlegeli), named SsSOCS1a and SsSOCS1b. SsSOCS1a and SsSOCS1b contained conserved structural and functional domains including KIR region, ESS region, SH2 domain and SOCS box. SsSOCS1a and SsSOCS1b were distributed ubiquitously in all the detected tissues with the higher expression level in liver and spleen. After stimulation in vivo with Vibrio anguillarum and Edwardsiella tarda, the mRNA expression of SsSOCS1a and SsSOCS1b were induced in most of the immune-related tissues, including head kidney, spleen and liver. Meanwhile, poly I:C and IFNγ up-regulated the expression of SsSOCS1a and SsSOCS1b that reached the highest level at 24 h in macrophages in vitro. Luciferase assays in HEK293 cells showed SsSOCS1a and SsSOCS1b had the similar function in inhibiting ISRE activity after poly I:C and IFNγ treatment. Furthermore, KIR domain in black rockfish was determined to have a negative regulatory role in IFN signaling. SsSOCS1a and SsSOCS1b were found to interact strongly with each other by Co-immunoprecipitation analyses. These results indicated that the function of SOCS1 in the negative regulation of IFN signaling is conserved from teleost to mammals which will be helpful to further understanding of the biological functions of teleosts SOCS1 in innate immunity.

Application and progress of the detection technologies in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has a very high incidence and fatality rate, and in most cases, it is already at an advanced stage when diagnosed. Therefore, early prevention and detection of HCC are two of the most effective strategies. However, the methods recommended in the practice guidelines for the detection of HCC cannot guarantee high sensitivity and specificity except for the liver biopsy, which is known as the "gold standard". In this review, we divided the detection of HCC into pre-treatment diagnosis and post-treatment monitoring, and found that in addition to the traditional imaging detection and liver biopsy, alpha fetoprotein (AFP), lens culinaris-agglutinin-reactive fraction of AFP (AFP-L3), protein induced by vitamin K absence or antagonist-II (PIVKA-II) and other biomarkers are excellent biomarkers for HCC, especially when they are combined together. Most notably, the emerging liquid biopsy shows great promise in detecting HCC. In addition, lactic dehydrogenase (LDH), suppressor of cytokine signaling (SOCS) and other relevant biomarkers may become promising biomarkers for HCC post-treatment monitoring. Through the detailed introduction of the diagnostic technology of HCC, we can have a detailed understanding of its development process and then obtain some enlightenment from the diagnosis, to improve the diagnostic rate of HCC and reduce its mortality.

Pathogenic insights from genetic causes of autoinflammatory inflammasomopathies and interferonopathies

A number of systemic autoinflammatory diseases arise from gain-of-function mutations in genes encoding IL-1-activating inflammasomes or cytoplasmic nucleic acid sensors including the receptor and sensor STING and result in increased IL-1 and type I interferon production, respectively. Blocking these pathways in human diseases has provided proof-of-concept, confirming the prominent roles of these cytokines in disease pathogenesis. Recent insights into the multilayered regulation of these sensor pathways and insights into their role in amplifying the disease pathogenesis of monogenic and complex genetic diseases spurred new drug development targeting the sensors. This review provides insights into the pathogenesis and genetic causes of these "prototypic" diseases caused by gain-of function mutations in IL-1-activating inflammasomes (inflammasomopathies) and in interferon-activating pathways (interferonopathies) including STING-associated vasculopathy with onset in infancy, Aicardi-Goutieres syndrome, and proteasome-associated autoinflammatory syndromes that link activation of the viral sensors STING, "self" nucleic acid metabolism, and the ubiquitin-proteasome system to "type I interferon production" and human diseases. Clinical responses and biomarker changes to Janus kinase inhibitors confirm a role of interferons, and a growing number of diseases with "interferon signatures" unveil extensive cross-talk between major inflammatory pathways. Understanding these interactions promises new tools in tackling the significant clinical challenges in treating patients with these conditions.

Identification of the Prognostic Value Among Suppressor Of Cytokine Signaling Family Members in Kidney Renal Clear Cell Carcinoma

Background: Kidney renal clear cell carcinoma (KIRC) has become one of the most prevalent malignancies worldwide and remains a crucial cause of cancer-related morbidity and mortality. Aberrant activation of the JAK/STAT pathway acts as an important role in KIRC. The suppressor of cytokine signaling (SOCS) family members are the key negative regulators of the JAK/STAT pathway. SOCS family members have been verified to act as significant roles in regulating cellular responses to many cytokines and growth factors. However, whether the expression levels of SOCS affect the prognosis of patients with KIRC is still elusive.

Methods: We first evaluated the expression of SOCS family genes in KIRC and determined the correlation between SOCS expression and different clinicopathological features. Then, we analyzed the genetic alterations, potential functions, transcription factor targets, and immune infiltration of SOCS family members based on the information available on public databases. Finally, we assessed the prognostic value of differentially expressed SOCS family members.

Results: The expression levels of SOCS2, SOCS4, SOCS6, SOCS7, and CISH were downregulated in KIRC, and all SOCS genes were associated with clinicopathological features of patients with KIRC. SOCS family members have been predominantly related to protein binding, signaling adaptor activity, and JAK/STAT cascade. We found that STAT3, STAT6, and IRF1 are the key transcription factors that may be participated in the regulation of SOCS. We also found an association between the expression levels of SOCS and the immune infiltrates of KIRC. Finally, we have illuminated that SOCS1 and SOCS3 are risky genes, whereas SOCS2, SOCS4, SOCS6, SOCS7, and CISH are some of the protective genes for patients with KIRC; based on these, we have created a KIRC prognostic index for predicting the prognosis of patients of KIRC.

Conclusion: Our study may contribute to further understanding the functions of SOCS genes in KIRC, which may help clinicians in selecting the appropriate drugs and predicting the outcomes for patients with KIRC.

Effect Mechanism of Electroacupuncture at ST36 on the Injured Extensor Digitorum Longus in the Jumping Rat Model Based on mRNA-Seq Analysis

The key target and regulatory mechanism of electroacupuncture of Zusanli (ST36) on extensor longus muscle injury in a jumping rat model were investigated. To this end, 24 female SD rats were randomly divided into the following four groups: no-treatment control group (NON), 6-week jumping group (J6O), electroacupuncture group after 6-week jumping (J6A), and natural recovery group after 6-week jumping (J6N). After 6 weeks of jumping, in the electroacupuncture group (J6A), electroacupuncture stimulation was applied at Zusanli(ST36) for 20 min per day over the course of 5 days. In the natural recovery group (J6N), rats were fastened with a special apparatus without electroacupuncture stimulation for 20 min at the same time. Transmission electron microscopy, transcriptome sequencing and analysis, Western blotting assay and immunofluorescence staining were performed at the end of our experiment. The recovery effect of J6A rats was more obvious than that of J6N rats and J6O rats as indicated by changes of infiltration of inflammatory cells and morphological structure. Notably, the morphological structure of J6A rats was closer to NON rats in the observation of transmission electron microscopy. CISH/STAT3 regulation was identified by mRNA-seq. The pro-inflammatory response to STAT3 activation was alleviated through up-regulating the expression of CISH protein in J6A rats relative to J6O rats. The level of BAX was decreased and the level of Bcl-2 level was increased in J6A rats relative to J6O rats. Moreover, when compared to J6N rats, the level of Bcl-2 was significantly up-regulated in J6A rats. Increased caspase-3 expression but decreased CDKN2α expression was shown in J6A rats relative to NON rats. These results indicate that the potential mechanism underlying electroacupuncture stimulation of Zusanli (ST36) in repairing the injured extensor digitorum longus following overused jumping may be attributed to CISH/STAT3 regulation of proteins associated with inflammation, apoptosis, and proliferation.

ORF3a Protein of Severe Acute Respiratory Syndrome Coronavirus 2 Inhibits Interferon-Activated Janus Kinase/Signal Transducer and Activator of Transcription Signaling via Elevating Suppressor of Cytokine Signaling 1

Coronavirus disease 2019 (COVID-19) has caused a crisis to global public health since its outbreak at the end of 2019. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen of COVID-19, appears to efficiently evade the host immune responses, including interferon (IFN) signaling. Several SARS-CoV-2 viral proteins are believed to involve in the inhibition of IFN signaling. In this study, we discovered that ORF3a, an accessory protein of SARS-CoV-2, inhibited IFN-activated Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling via upregulating suppressor of cytokine signaling 1 (SOCS1), a negative regulator of cytokine signaling. ORF3a induced SOCS1 elevation in a dose- and time-dependent manner. RNAi-mediated silencing of SOCS1 efficiently abolished ORF3a-induced blockage of JAK/STAT signaling. Interestingly, we found that ORF3a also promoted the ubiquitin-proteasomal degradation of Janus kinase 2 (JAK2), an important kinase in IFN signaling. Silencing of SOCS1 by siRNA distinctly blocked ORF3a-induced JAK2 ubiquitination and degradation. These results demonstrate that ORF3a dampens IFN signaling via upregulating SOCS1, which suppressed STAT1 phosphorylation and accelerated JAK2 ubiquitin-proteasomal degradation. Furthermore, analysis of ORF3a deletion constructs showed that the middle domain of ORF3a (amino acids 70-130) was responsible for SOCS1 upregulation. These findings contribute to our understanding of the mechanism of SARS-CoV-2 antagonizing host antiviral response.

The Yin and Yang of Type I IFNs in Cancer Promotion and Immune Activation

Type I Interferons (IFNs) are key regulators of natural and therapy-induced host defense against viral infection and cancer. Several years of remarkable progress in the field of oncoimmunology have revealed the dual nature of these cytokines. Hence, Type I IFNs may trigger anti-tumoral responses, while leading immune dysfunction and disease progression. This dichotomy relies on the duration and intensity of the transduced signaling, the nature of the unleashed IFN stimulated genes, and the subset of responding cells. Here, we discuss the role of Type I IFNs in the evolving relationship between the host immune system and cancer, as we offer a view of the therapeutic strategies that exploit and require an intact Type I IFN signaling, and the role of these cytokines in inducing adaptive resistance. A deep understanding of the complex, yet highly regulated, network of Type I IFN triggered molecular pathways will help find a timely and immune"logical" way to exploit these cytokines for anticancer therapy.

IGF-1 and IGFBP-3 in Inflammatory Cachexia

Inflammation induces a wide response of the neuroendocrine system, which leads to modifications in all the endocrine axes. The hypothalamic–growth hormone (GH)–insulin-like growth factor-1 (IGF-1) axis is deeply affected by inflammation, its response being characterized by GH resistance and a decrease in circulating levels of IGF-1. The endocrine and metabolic responses to inflammation allow the organism to survive. However, in chronic inflammatory conditions, the inhibition of the hypothalamic–GH–IGF-1 axis contributes to the catabolic process, with skeletal muscle atrophy and cachexia. Here, we review the changes in pituitary GH secretion, IGF-1, and IGF-1 binding protein-3 (IGFBP-3), as well as the mechanism that mediated those responses. The contribution of GH and IGF-1 to muscle wasting during inflammation has also been analyzed.

TYK2 in Cancer Metastases: Genomic and Proteomic Discovery

Advances in genomic analysis and proteomic tools have rapidly expanded identification of biomarkers and molecular targets important to cancer development and metastasis. On an individual basis, personalized medicine approaches allow better characterization of tumors and patient prognosis, leading to more targeted treatments by detection of specific gene mutations, overexpression, or activity. Genomic and proteomic screens by our lab and others have revealed tyrosine kinase 2 (TYK2) as an oncogene promoting progression and metastases of many types of carcinomas, sarcomas, and hematologic cancers. TYK2 is a Janus kinase (JAK) that acts as an intermediary between cytokine receptors and STAT transcription factors. TYK2 signals to stimulate proliferation and metastasis while inhibiting apoptosis of cancer cells. This review focuses on the growing evidence from genomic and proteomic screens, as well as molecular studies that link TYK2 to cancer prevalence, prognosis, and metastasis. In addition, pharmacological inhibition of TYK2 is currently used clinically for autoimmune diseases, and now provides promising treatment modalities as effective therapeutic agents against multiple types of cancer.

Genomic evidence of adaptive evolution in the reptilian SOCS gene family

The suppressor of the cytokine signaling (SOCS) family of proteins play an essential role in inhibiting cytokine receptor signaling by regulating immune signal pathways. Although SOCS gene functions have been examined extensively, no comprehensive study has been performed on this gene family's molecular evolution in reptiles. In this study, we identified eight canonical SOCS genes using recently-published reptilian genomes. We used phylogenetic analysis to determine that the SOCS genes had highly conserved evolutionary dynamics that we classified into two types. We identified positive SOCS4 selection signals in whole reptile lineages and SOCS2 selection signals in the crocodilian lineage. Selective pressure analyses using the branch model and Z-test revealed that these genes were under different negative selection pressures compared to reptile lineages. We also concluded that the nature of selection pressure varies across different reptile lineages on SOCS3, and the crocodilian lineage has experienced rapid evolution. Our results may provide a theoretical foundation for further analyses of reptilian SOCS genes' functional and molecular mechanisms, as well as their roles in reptile growth and development.

The LINC01119-SOCS5 axis as a critical theranostic in triple-negative breast cancer

The development of triple-negative breast cancer (TNBC) is critically regulated by certain tumor-microenvironment-associated cells called mesenchymal stem/stromal cells (MSCs), which we and others have shown promote TNBC progression by activating pro-malignant signaling in neighboring cancer cells. Characterization of these cascades would better our understanding of TNBC biology and bring about therapeutics that eliminate the morbidity and mortality associated with advanced disease. Here, we focused on the emerging class of RNAs called long non-coding RNAs or lncRNAs and utilized a MSC-supported TNBC progression model to identify specific family members of functional relevance to TNBC pathogenesis. Indeed, although some have been described to play functional roles in TNBC, activities of lncRNAs as mediators of tumor-microenvironment-driven TNBC development remain to be fully explored. We report that MSCs stimulate robust expression of LINC01119 in TNBC cells, which in turn induces suppressor of cytokine signaling 5 (SOCS5), leading to accelerated cancer cell growth and tumorigenesis. We show that LINC01119 and SOCS5 exhibit tight correlation across multiple breast cancer gene sets and that they are highly enriched in TNBC patient cohorts. Importantly, we present evidence that the LINC01119-SOCS5 axis represents a powerful prognostic indicator of adverse outcomes in TNBC patients, and demonstrate that its repression severely impairs cancer cell growth. Altogether, our findings identify LINC01119 as a major driver of TNBC development and delineate critical non-coding RNA theranostics of potential translational utility in the management of advanced TNBC, a class of tumors in most need of effective and targeted therapy.

lncRNA HAND2-AS1 Inhibits Liver Cancer Cell Proliferation and Migration by Upregulating SOCS5 to Inactivate the JAK-STAT Pathway

Objective: lncRNA HAND2 antisense RNA 1 (HAND2-AS1) is consistently well recognized to suppress multiple tumors, while its function was uncertified in liver cancer. Materials and Methods: qRT-PCR analysis and TCGA database discovered the expression in liver cancer. CCK-8 and Transwell migration assay demonstrated the impact of HAND2-AS1 on cell proliferation and migration. Bioinformatic analysis and luciferase reporter assay were utilized to monitor the binding between HAND2-AS1 or SOCS5 mRNA and miR-3118. The function of SOCS5 on inactivating the JAK-STAT pathway was confirmed through Western blot assays. Rescue experiments unmasked that HAND2-AS1-mediated SOCS5 affected cell proliferation and migration through the JAK-STAT pathway in liver cancer. Results: The authors discovered the downregulated HAND2-AS1 in liver cancer cells. HAND2-AS1 augmentation apparently impaired the capacity of liver cancer viability, proliferation, and migration. Cytoplasmic HAND2-AS1 directly bound to miR-3118 and released SOCS5, leading to upregulation of SOCS5. Next, the negative regulator role of SOCS5 in the adjusting JAK-STAT pathway was reconfirmed in this study. Conclusions: HAND2-AS1 enhanced inactivation of the JAK-STAT pathway through sponging miR-3118 and facilitating SOCS5 to retard cell proliferation and migration in liver cancer.

The Role of Type I Interferons in the Pathogenesis and Treatment of COVID-19

Type I interferons (IFN-I) were first discovered over 60 years ago in a classical experiment by Isaacs and Lindenman, who showed that IFN-Is possess antiviral activity. Later, it became one of the first approved protein drugs using heterologous protein expression systems, which allowed its large-scale production. It has been approved, and widely used in a pleiotropy of diseases, including multiple-sclerosis, hepatitis B and C, and some forms of cancer. Preliminary clinical data has supported its effectiveness against potential pandemic pathogens such as Ebola and SARS. Still, more efficient and specific drugs have taken its place in treating such diseases. The COVID-19 global pandemic has again lifted the status of IFN-Is to become one of the more promising drug candidates, with initial clinical trials showing promising results in reducing the severity and duration of the disease. Although SARS-CoV-2 inhibits the production of IFNβ and thus obstructs the innate immune response to this virus, it is sensitive to the antiviral activity of externally administrated IFN-Is. In this review I discuss the diverse modes of biological actions of IFN-Is and how these are related to biophysical parameters of IFN-I-receptor interaction and cell-type specificity in light of the large variety of binding affinities of the different IFN-I subtypes towards the common interferon receptor. Furthermore, I discuss how these may guide the optimized use IFN-Is in combatting COVID-19.

Perspectives Regarding the Intersections between STAT3 and Oxidative Metabolism in Cancer

Signal transducer and activator of transcription 3 (STAT3) functions as a major molecular switch that plays an important role in the communication between cytokines and kinases. In this role, it regulates the transcription of genes involved in various biochemical processes, such as proliferation, migration, and metabolism of cancer cells. STAT3 undergoes diverse post-translational modifications, such as the oxidation of cysteine by oxidative stress, the acetylation of lysine, or the phosphorylation of serine/threonine. In particular, the redox modulation of critical cysteine residues present in the DNA-binding domain of STAT3 inhibits its DNA-binding activity, resulting in the inactivation of STAT3-mediated gene expression. Accumulating evidence supports that STAT3 is a key protein that acts as a mediator of metabolism and mitochondrial activity. In this review, we focus on the post-translational modifications of STAT3 by oxidative stress and how the modification of STAT3 regulates cell metabolism, particularly in the metabolic pathways in cancer cells.

Inhibition of let-7b-5p contributes to an anti-tumorigenic macrophage phenotype through the SOCS1/STAT pathway in prostate cancer

Background

Dysfunction of microRNAs (miRNAs) is a major cause of aberrant expression of inflammatory cytokines and contributes to macrophage polarization. Proinflammatory M1 macrophages promote T helper (Th) 1 responses and show tumoricidal activity, whereas M2 macrophages display regulatory functions in tissue repair and remodeling and promote Th2 immune responses. Previous studies have shown that miRNA let-7 is associated with cellular differentiation and that the expression of let-7b-5p is significantly augmented in M2 macrophages. However, the mechanism by which let-7b-5p regulates macrophage differentiation in prostate cancer (PCa) remains largely unknown.

Methods

Human macrophages were induced by blood monocytes from healthy male donors, and M1 macrophages were polarized by stimulating them overnight with 100 ng/ml of lipopolysaccharides and 100 ng/ml of IFN-γ. Conditioned medium from PC-3 cells was used to induce prostatic macrophages (M-CMs) in vitro, and we then transfected let-7b-5p mimics or inhibitors into M1 and M-CMs for 72 h. The expression of cluster of differentiation 206 (CD206) in each group was detected with the High-Throughput Connotation of Imaging System. We used quantitative real-time polymerase chain reaction (qRT-PCR) to examine the expression of the inflammatory cytokines IL-10, IL-12, IL-13, TNF-alpha, and let-7b in macrophages. SOCS1 protein levels were evaluated by ELISA, and the phosphorylation difference in STAT family member proteins was analyzed using CST signal-pathway chip. Phagocytosis by macrophages and the effect of macrophages on the proliferation of prostate cancer PC-3 cells were evaluated with phagocytosis assay or the Cell Counting Kit-8 (CCK-8) and colony formation assay. The relationship between SOCS1 and let-7b-5p was confirmed with a dual-luciferase reporter.

Results

The expression of cluster of differentiation 206 (CD206, a M2-like macrophage surface molecule) was significantly increased in M1 macrophages treated with let-7b-5p mimics, while CD206 expression was decreased in M-CMs treated with let-7b-5p inhibitors. Overexpression or knockdown of let-7b-5p significantly affected the expression of inflammatory factors in macrophages-including interleukin 10 (IL-10), IL-12, IL-13, and tumor necrosis factor alpha. Let-7b-5p downregulated the expression of suppressor of cytokine signaling 1 (SOCS1) and increased the phosphorylation of signal transducer and activator of transcription 1 (STAT1), STAT3, and STAT5a proteins in M-CMs and M1 macrophages with let-7b-5p mimics relative to the other groups. In addition, with the elevated expression of let-7b-5p, the phagocytosis by macrophages showed a commensurate and significant decrease. As a result, M-CMs treated with let-7b-5p inhibitors reduced the proliferation of PC-3 PCa cells.

Conclusions

Collectively, these data indicated that let-7b-5p may regulate M2 polarization through the SOCS1/STAT pathway and that reversal of M2 differentiation by let-7b-5p inhibitors enhanced macrophage phagocytosis, ultimately inhibiting the proliferation of PCa cells.

SOCS Proteins Participate in the Regulation of Innate Immune Response Caused by Viruses

The host immune system has multiple innate immune receptors that can identify, distinguish and react to viral infections. In innate immune response, the host recognizes pathogen-associated molecular patterns (PAMP) in nucleic acids or viral proteins through pathogen recognition receptors (PRRs), especially toll-like receptors (TLRs) and induces immune cells or infected cells to produce type I Interferons (IFN-I) and pro-inflammatory cytokines, thus when the virus invades the host, innate immunity is the earliest immune mechanism. Besides, cytokine-mediated cell communication is necessary for the proper regulation of immune responses. Therefore, the appropriate activation of innate immunity is necessary for the normal life activities of cells. The suppressor of the cytokine signaling proteins (SOCS) family is one of the main regulators of the innate immune response induced by microbial pathogens. They mainly participate in the negative feedback regulation of cytokine signal transduction through Janus kinase signal transducer and transcriptional activator (JAK/STAT) and other signal pathways. Taken together, this paper reviews the SOCS proteins structures and the function of each domain, as well as the latest knowledge of the role of SOCS proteins in innate immune caused by viral infections and the mechanisms by which SOCS proteins assist viruses to escape host innate immunity. Finally, we discuss potential values of these proteins in future targeted therapies.

Exosome-mediated miR-9-5p promotes proliferation and migration of renal cancer cells both in vitro and in vivo by targeting SOCS4

Exosomes secreted by cancer cells play important roles in tumor progression by interacting with cell receptors. Renal cancer derived exosomes contain miRNAs which are associated with cell proliferation and invasion. Micro RNA 9-5 (miR-9-5) is highly expressed in the serum of renal cancer patients with advanced (tumor size - node - metastasis) TNM stage and Fuhrman grade. miR-9-5p is extensively expressed in exosomes derived from renal cancer cells. Overexpression of miR-9-5p promotes proliferation and invasion of A-704 (a cancer cell line of human kidney) cells via targeting and deregulating SOCS4 mRNA. Inhibition of the Janus kinase (JAK)/signaling transducer and activator of transcription (STAT) pathway by SOCS4 will be reduced, which leads to phosphorylation of STAT3 and JAK. Activated cytokine signaling promotes cell proliferation and invasion, and inhibits apoptosis. Moreover, overexpression of SOCS4 reduces miR-9-5p levels and plays an opposite role in cell. To conclude, exosomal miR-9-5p plays important roles in renal cancer both in vivo and in vitro, indicating it may be used as biomarker for diagnosis and for monitoring the efficacy if therapy.

Duck Tembusu virus promotes the expression of suppressor of cytokine signaling 1 by downregulating miR-148a-5p to facilitate virus replication

Duck Tembusu virus (DTMUV), an emerging infectious pathogen, has caused severe disease in ducks and huge economic losses to the poultry industry in China since 2009. Despite considerable advances in understanding the effects of microRNAs on host antiviral immune responses, it remains unclear how miRNAs regulate DTMUV replication in duck embryo fibroblast (DEF) cells. This study aims to clarify the role of host microRNA-148a-5p (miR-148a-5p) in regulating DTMUV replication by targeting SOCS1. First, we found that during DTMUV infection, the expression of miR-148a-5p in DEFs was downregulated in a time-dependent and dose-dependent manner, while the expression of SOCS1 was significantly upregulated. In addition, we found that when miR-148a-5p mimics were transfected into DEFs, viral RNA copies, viral E protein expression levels and viral titres, which represent viral replication and proliferation, were significantly downregulated, while the opposite result was observed when miR-148a-5p inhibitor was transfected into DEFs. Next, we found that SOCS1 was the target gene of miR-148a-5p through software analysis. Therefore, we further confirmed that SOCS1 was the target of miR-148a-5p and that miR-148a-5p could negatively regulate the expression of SOCS1 at the mRNA and protein levels. Furthermore, our results indicated that overexpression of SOCS1 promoted DTMUV replication, while knockdown of SOCS1 inhibited DTMUV replication. Finally, we found that in DTMUV-infected DEFs, the overexpression of SOCS1 inhibited the production of IFN-α and IFN-β, while knocking down SOCS1 produced the opposite result. This indicates that during DTMUV infection, the virus promotes the expression of SOCS1 by downregulating the expression of miR-148a-5p, while the upregulation of SOCS1 suppresses the production of type I interferon and promotes virus replication. Taken together, these findings provide new insights into virus-host interactions during DTMUV infection and provide potential new antiviral treatment strategies for DTMUV infection.

Cullin-RING Ligase 5: Functional characterization and its role in human cancers

Cullin-RING ligase 5 (CRL5) is a multi-protein complex and consists of a scaffold protien cullin 5, a RING protein RBX2 (also known as ROC2 or SAG), adaptor proteins Elongin B/C, and a substrate receptor protein SOCS. Through targeting a variety of substrates for proteasomal degradation or modulating various protein-protein interactions, CRL5 is involved in regulation of many biological processes, such as cytokine signal transduction, inflammation, viral infection, and oncogenesis. As many substrates of CRL5 are well-known oncoproteins or tumor suppressors, abnormal regulation of CRL5 is commonly found in human cancers. In this review, we first briefly introduce each of CRL5 components, and then discuss the biological processes regulated by four members of SOCS-box-containing substrate receptor family through substrate degradation. We next describe how CRL5 is hijacked by a variety of viral proteins to degrade host anti-viral proteins, which facilitates virus infection. We further discuss the regulation of CUL5 and its various roles in human cancers, acting as either a tumor suppressor or an oncoprotein in a context-dependent manner. Finally, we propose novel insights for future perspectives on the validation of cullin5 and other CRL5 components as potential targets, and possible targeting strategies to discover CRL5 inhibitors for anti-cancer and anti-virus therapies.

A Probabilistic Classification Tool for Genetic Subtypes of Diffuse Large B Cell Lymphoma with Therapeutic Implications

The development of precision medicine approaches for diffuse large B cell lymphoma (DLBCL) is confounded by its pronounced genetic, phenotypic, and clinical heterogeneity. Recent multiplatform genomic studies revealed the existence of genetic subtypes of DLBCL using clustering methodologies. Here, we describe an algorithm that determines the probability that a patient's lymphoma belongs to one of seven genetic subtypes based on its genetic features. This classification reveals genetic similarities between these DLBCL subtypes and various indolent and extranodal lymphoma types, suggesting a shared pathogenesis. These genetic subtypes also have distinct gene expression profiles, immune microenvironments, and outcomes following immunochemotherapy. Functional analysis of genetic subtype models highlights distinct vulnerabilities to targeted therapy, supporting the use of this classification in precision medicine trials.

Suppressors of cytokine signaling proteins as modulators of development and innate immunity of insects

The suppressors of cytokine signaling (SOCS) are a family of intracellular molecules. Many members of this family have been reported to be involved in various physiological processes in invertebrates and vertebrates (e.g., developmental process and immune response). The functions of SOCS molecules seem to remain conserved in animals throughout evolutionary history. The members of the SOCS family play vital roles in the physiological processes by regulating the extent and duration of signaling activities of both Janus Kinase-Signal Transducer and Activators of Transcription (JAK-STAT) and epidermal growth factor receptor (EGFR) pathways in vivo. So far, in different insect species, a variable number of SOCS and SOCS box domain-containing proteins have been identified. These proteins are categorized into different types based on their sequence diversification, leading to an alteration in structure and regulatory function. The biological roles of the many SOCS proteins have been established as a negative or positive regulator of the signaling pathways, as mentioned earlier. Here, we discussed the existing knowledge on the SOCS proteins and their involvement in different biological functions in insects, and future perspectives to further elucidate their physiological roles.

gga-miR-27b-3p enhances type I interferon expression and suppresses infectious bursal disease virus replication via targeting cellular suppressors of cytokine signaling 3 and 6 (SOCS3 and 6)

MicroRNAs are small noncoding RNAs playing an important role in host response to pathogenic infection. Here we show that IBDV infection induced the demethylation of the pre-miR-27 promoter and upregulated gga-miR-27b-3p expression. We found that ectopic expression of miR-27b-3p in DF-1 cells enhanced the expression of chicken IFN-β, IRF3 and NF-κB, via directly targeting cellular suppressors of cytokine signaling 3 and 6 (SOCS3 and 6), inhibiting IBDV replication in host cells, while inhibition of endogenous miR-27b-3p by its inhibitors suppressed the expression of IFN-β, IRF3 and NF-κB, enhancing SOCS3 and 6 expressions and facilitating IBDV replication. Furthermore, transfection of DF-1 cells with miR-27b-3p markedly increased phosphorylation of STAT1 on Tyr701 in cells post chIFN-γ treatment. On the contrary, inhibition of endogenous miR-27b-3p reduced phosphorylation of STAT1 on Tyr701 in cells with chIFN-γ treatment. These findings indicate that gga-miR-27b-3p serves as an inducible antiviral mediator in host response to IBDV infection.

Induction of SOCS Expression by EV71 Infection Promotes EV71 Replication

Enterovirus 71 (EV71) is the causative pathogen of hand, foot, and mouth disease (HFMD). However, no effective antiviral therapy is currently available. Some viruses could escape the host's innate immunity by upregulating suppressor of cytokine signaling (SOCS) proteins. Until now, whether EV71 evades the host immune system by regulating the expression of SOCS proteins remains unknown. In this study, we found that EV71 infection promoted SOCS expression at both mRNA and protein levels in vitro and in vivo. Consistently, the infectivity of EV71 was decreased significantly in the SOCS3 or SOCS1 knockdown cells, suggesting that SOCS1 and especially SOCS3 are crucial for EV71 infection. Further investigation showed that SOCS3 promoted virus infection by inhibiting interferon-induced STAT3 phosphorylation. SOCS1 and SOCS3 mRNA expressions were independent on virus-induced type I interferon expression but were blocked by the inhibitor of NF-κB. Therefore, EV71 infection stimulates the expression of SOCS proteins in an interferon-independent way and negatively regulates the JAK/STAT signaling pathway, thus escaping host immunity. All these results may add new information to the mechanism of EV71 in fighting against type I interferon responses.

miR-26a Inhibits Feline Herpesvirus 1 Replication by Targeting SOCS5 and Promoting Type I Interferon Signaling

In response to viral infection, host cells activate various antiviral responses to inhibit virus replication. While feline herpesvirus 1 (FHV-1) manipulates the host early innate immune response in many different ways, the host could activate the antiviral response to counteract it through some unknown mechanisms. MicroRNAs (miRNAs) which serve as a class of regulatory factors in the host, participate in the regulation of the host innate immune response against virus infection. In this study, we found that the expression levels of miR-26a were significantly upregulated upon FHV-1 infection. Furthermore, FHV-1 infection induced the expression of miR-26a via a cGAS-dependent pathway, and knockdown of cellular cGAS significantly blocked the expression of miR-26a induced by poly (dA:dT) or FHV-1 infection. Next, we investigated the biological function of miR-26a during viral infection. miR-26a was able to increase the phosphorylation of STAT1 and promote type I IFN signaling, thus inhibiting viral replication. The mechanism study showed that miR-26a directly targeted host SOCS5. Knockdown of SOCS5 increased the phosphorylation of STAT1 and enhanced the type I IFN-mediated antiviral response, and overexpression of suppressor of the cytokine signalling 5 (SOCS5) decreased the phosphorylation of STAT1 and inhibited the type I IFN-mediated antiviral response. Meanwhile, with the knockdown of SOCS5, the upregulated expression of phosphorylated STAT1 and the anti-virus effect induced by miR-26a were significantly inhibited. Taken together, our data demonstrated a new strategy of host miRNAs against FHV-1 infection by enhancing IFN antiviral signaling.

CgSOCS6 negatively regulates the expression of CgIL17s and CgDefh1 in the pacific oyster Crassostrea gigas

As a family of negatively feedback regulating factors, the suppressor of cytokine signaling (SOCS) can depress cytokine signal transduction, and eventually modulate growth, development, differentiation, and immune response. In the present study, a SOCS homologue (designated as CgSOCS6) was identified from oyster Crassostrea gigas. The open reading frame of CgSOCS6 cDNA was of 1167 bp encoding a peptide of 388 amino acid residues with a central Src homology 2 (SH2) domain, a conserved C-terminal SOCS box, and a nucleus localization sequence (NLS) in its N-terminus. The deduced amino acid sequence of CgSOCS6 shared 37.9-45.5% similarity with other SOCS6/7 family members. In the unrooted phylogenetic tree, CgSOCS6 was clustered with EsSOCS6 from Chinese mitten crab Eriocheir sinensis and assigned into the SOCS6/7 group. The mRNA transcripts of CgSOCS6 were constitutively distributed in all the tested tissues, with the highest level in hemocytes. After lipopolysaccharide (LPS) stimulation, the mRNA expression of CgSOCS6 in hemocytes was significantly up-regulated to the highest level at 6 h (8.48-fold compared to the control group, p < 0.01), and then kept at a relatively higher level from 12 h to 72 h. CgSOCS6 protein could be translocated into the hemocyte nucleus after LPS stimulation. The mRNA expressions of interleukin 17-4 (CgIL17-4), CgIL17-5, and defensin (CgDefh1) in the hemocytes of CgSOCS6-knockdown oysters increased significantly (2.55-fold, 2.68-fold, 4.68-fold of that in EGFP-RNAi oysters, p < 0.05, p < 0.05, p < 0.001, respectively) after LPS stimulation. These findings suggested that CgSOCS6 was involved in the oyster immune response by regulating the expressions of CgIL17-4, CgIL17-5, and CgDefh1.

Insights into the Evolution of the Suppressors of Cytokine Signaling (SOCS) Gene Family in Vertebrates

The SOCS family are key negative regulators of cytokine and growth factor signaling. Typically, 8-17 SOCS genes are present in vertebrate species with eight known in mammals, classified as type I (SOCS4-7) and type II (CISH and SOCS1-3) SOCS. It was believed that the type II SOCS were expanded through the two rounds of whole genome duplication (1R and 2R WGDs) from a single CISH/SOCS1-3 precursor. Previously, 12 genes were identified in rainbow trout but here we report 15 additional loci are present, and confirm 26 of the genes are expressed, giving rainbow trout the largest SOCS gene repertoire identified to date. The discovery of the additional SOCS genes in trout has led to a novel model of SOCS family evolution, whereby the vertebrate SOCS gene family was derived from CISH/SOCS2, SOCS1/SOCS3, SOCS4/5, SOCS6, and SOCS7 ancestors likely present before the two WGD events. It is also apparent that teleost SOCS2b, SOCS4, and SOCS5b molecules are not true orthologues of mammalian SOCS2, SOCS4, and SOCS5, respectively. The rate of SOCS gene structural changes increased from 2R vertebrates, to 4R rainbow trout, and the genes with structural changes show large differences and low correlation coefficient of expression levels relative to their paralogues, suggesting a role of structural changes in expression and functional diversification. This study has important impacts in the functional prediction and understanding of the SOCS gene family in different vertebrates, and provides a framework for determining how many SOCS genes could be expected in a particular vertebrate species/lineage.

Targeting SOCS Proteins to Control JAK-STAT Signalling in Disease

Defective regulation of the Janus kinase-signal transducer and activator of transcription (JAK-STAT) signalling pathway in cancers, haematological diseases, and chronic inflammatory conditions highlights its clinical significance. While several biologic and small molecule therapeutics targeting this pathway have been developed, these have several limitations. Therefore, there is a need to identify new targets for intervention. Suppressor of cytokine signalling (SOCS) proteins are a family of inducible inhibitors of cytokine receptors that activate the JAK-STAT pathway. Here we propose that newly identified mechanisms controlling SOCS function could be exploited to develop molecularly targeted drugs with unique modes of action to inhibit JAK-STAT signalling in disease.

gga-miR-454 suppresses infectious bursal disease virus (IBDV) replication via directly targeting IBDV genomic segment B and cellular Suppressors of Cytokine Signaling 6 (SOCS6)

MicroRNAs (miRNAs), as post-transcriptional regulators, play important roles in the process of viral infection through inhibiting virus replication or modulating host immune response. However, the role of miRNAs in host response against infectious bursal disease virus (IBDV) infection is still unclear. In this study, we found that gga-miR-454 of the host was decreased in response to IBDV infection and that transfection of DF-1 cells with miR-454 inhibited IBDV replication via directly targeting the specific sequence of IBDV genomic segment B, while blockage of endogenous miR-454 by inhibitors enhanced virus replication. Furthermore, gga-miR-454 increased the expression of IFN-β by targeting Suppressors of Cytokine Signaling 6 (SOCS6), enhancing the antiviral response of host cells. These findings highlight a crucial role of gga-miR-454 in host defense against IBDV infection.

SOCS3 participates in cholinergic pathway regulation of synovitis in rheumatoid arthritis

Stimulation of the cholinergic inflammatory pathway can attenuate collagen-induced arthritis (CIA) and inhibit synovitis by Janus kinase (JAK) 2 and signal transducer and activator of transcription (STAT) 3 signaling. Suppressor of cytokine signaling (SOCS) protein can also regulate the inflammatory processes and activate JAK/STAT signal transduction, but its involvement in rheumatoid arthritis (RA) has not been demonstrated. This study investigated the effect of SOCS on cholinergic pathway regulation of synovitis in the fibroblast-like synoviocytes (FLSs) of RA and CIA mice. The effects of nicotine on SOCS1 and SOCS3 protein expression in FLSs were assayed by western blotting before and after transfection with a small interfering RNA oligonucleotide (SOCS3-siRNA or control-siRNA). Interleukin-6 was measured by enzyme-linked immunosorbent assay of SOCS3-siRNA and control-siRNA transfected FLS culture supernatants. Histopathological evaluation and immunohistochemical staining of SOCS3 were performed in joint tissue sections of control, CIA model, vagotomy, and nicotine-treated DBA/1 mice. Nicotine increased SOCS3 expression in the FLSs of RA. The inhibitory effect of nicotine on inflammatory factors was abolished by siRNA knockdown of SOCS3 protein expression. Nicotine increased the expression of SOCS3 protein in the synovium and reduced synovitis and bone erosion in CIA mice.

Identification of SNP markers associated with tolerance to ammonia toxicity by selective genotyping from de novo assembled transcriptome in Litopenaeus vannamei

The high concentration of ammonia from deteriorated aquaculture environments and the intensive culture system could increase the susceptibility to pathogens and even cause high mortality in Litopenaeus vannamei. In addition, we have revealed that the ammonia-tolerant shrimp also have high disease resistance in L. vannamei. In the present study, in order to identify SNP markers associated with tolerance to ammonia toxicity, we developed and characterized SNPs from our previous transcriptome sequencing data of ammonia-stressed and control groups, and a marker-trait association analysis was performed for marker-assisted selection (MAS) to increase production in L. vannamei. A total of 318,919 SNPs were identified from the transcriptome sequences, and 25,772 SNPs were found from the 1826 ammonia-responsive genes with functional annotation. We selected 49 SNPs from 26 ammonia-responsive genes that had strong homologies to known genes in the shrimp and probably involved in immune function as candidate markers for genotyping, among which 39 SNPs were polymorphic for further marker-trait association analysis with the ammonia-tolerant (AT) and ammonia-sensitive (AS) groups. Finally, 12 out of the 49 SNP markers were identified to be associated with ammonia tolerance, containing 10 loci with significantly different allele frequencies and 10 loci with significantly different genotyping frequencies between the AT and AS groups. Among the associated markers, the G allele of TSP-1 (the first locus from the thrombospondin gene), the A allele of TSP-3, and the C allele of XBP1-5 (the fifth locus from X-box binding protein 1) only presented in the AT groups, but they were absent from the AS groups, which would be the preference of the MAS for the ammonia-tolerant shrimp. In addition, when the 12 associated SNP markers were used for analysis, the genetic diversity of the AT groups were significantly higher than that of the AS groups, but when the 39 loci were used there was no difference. This is the first report for the markers associated with ammonia tolerance in this species, indirectly with disease resistance, which provided important potential for genetic selection to increase survival rate and production in shrimp farming.

MicroRNA gga-miR-130b Suppresses Infectious Bursal Disease Virus Replication via Targeting of the Viral Genome and Cellular Suppressors of Cytokine Signaling 5

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression posttranscriptionally through silencing or degrading their targets, thus playing important roles in the immune response. However, the role of miRNAs in the host response against infectious bursal disease virus (IBDV) infection is not clear. In this study, we show that the expression of a series of miRNAs was significantly altered in DF-1 cells after IBDV infection. We found that the miRNA gga-miR-130b inhibited IBDV replication via targeting the specific sequence of IBDV segment A and enhanced the expression of beta interferon (IFN-β) by targeting suppressors of cytokine signaling 5 (SOCS5) in host cells. These findings indicate that gga-miR-130b-3p plays a crucial role in host defense against IBDV infection.IMPORTANCE This work shows that gga-miR-130b suppresses IBDV replication via directly targeting the viral genome and cellular SOCS5, the negative regulator for type I interferon expression, revealing the mechanism underlying gga-miR-130-induced inhibition of IBDV replication. This information will be helpful for the understanding of how host cells combat pathogenic infection by self-encoded small RNA and furthers our knowledge of the role of microRNAs in the cell response to viral infection.

Characterization of Growth Hormone Resistance in Experimental and Ulcerative Colitis

Growth hormone (GH) resistance may develop as a consequence of inflammation during conditions such as inflammatory bowel disease, encompassing ulcerative colitis (UC). However, the specific role of the GH–insulin growth factor (IGF)-1-axis and/or the functional consequences of GH resistance in this condition are unclear. In situ hybridization targeting the GH receptor (GHR) and relevant transcriptional analyses were performed in patients with UC and in IL-10 knock-out mice with piroxicam accelerated colitis (PAC). Using cultured primary epithelial cells, the effects of inflammation on the molecular mechanisms governing GH resistance was verified. Also, the therapeutic potential of GH on mucosal healing was tested in the PAC model. Inflammation induced intestinal GH resistance in UC and experimental colitis by down-regulating GHR expression and up-regulating suppressor of cytokine signalling (SOCS) proteins. These effects are driven by pro-inflammatory mediators (tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6) as confirmed using primary epithelial cells. Treatment of experimental colitis with GH increased IGF-1 and body weight of the mice, but had no effects on colonic inflammation or mucosal healing. The high transcriptional similarity between UC and experimental colitis accentuates the formation of intestinal GH resistance during inflammation. Inflammation-induced GH resistance not only impairs general growth but induces a state of local resistance, which potentially impairs the actions of GH on mucosal healing during colitis when using long-acting GH therapy.

Dynamic Changes in the Splenic Transcriptome of Chickens during the Early Infection and Progress of Marek's Disease

Gallid alphaherpesvirus 2 (GaHV2) is an oncogenic avian herpesvirus inducing Marek’s disease (MD) and rapid-onset T-cell lymphomas. To reveal molecular events in MD pathogenesis and tumorigenesis, the dynamic splenic transcriptome of GaHV2-infected chickens during early infection and pathogenic phases has been determined utilizing RNA-seq. Based on the significant differentially expressed genes (DEGs), analysis of gene ontology, KEGG pathway and protein-protein interaction network has demonstrated that the molecular events happening during GaHV2 infection are highly relevant to the disease course. In the ‘Cornell Model’ description of MD, innate immune responses and inflammatory responses were established at early cytolytic phase but persisted until lymphoma formation. Humoral immunity in contrast began to play a role firstly in the intestinal system and started at late cytolytic phase. Neurological damage caused by GaHV2 is first seen in early cytolytic phase and is then sustained throughout the following phases over a long time period. During the proliferative phase many pathways associated with transcription and/or translation were significantly enriched, reflecting the cell transformation and lymphoma formation. Our work provides an overall view of host responses to GaHV2 infection and offers a meaningful basis for further studies of MD biology.

SOCS2 Binds to and Regulates EphA2 through Multiple Mechanisms

Suppressors of cytokine signaling (SOCS) proteins inhibit signaling by serving as substrate receptors for the Cullin5-RING E3 ubiquitin ligase (CRL5) and through a variety of CRL5-independent mechanisms. CRL5, SOCS2 and SOCS6 are implicated in suppressing transformation of epithelial cells. We identified cell proteins that interact with SOCS2 and SOCS6 using two parallel proteomics techniques: BioID and Flag affinity purification mass spectrometry. The receptor tyrosine kinase ephrin type-A receptor 2 (EphA2) was identified as a SOCS2-interacting protein. SOCS2-EphA2 binding requires the SOCS2 SH2 domain and EphA2 activation loop autophosphorylation, which is stimulated by Ephrin A1 (EfnA1) or by phosphotyrosine phosphatase inhibition. Surprisingly, EfnA1-stimulated EphA2-SOCS2 binding is delayed until EphA2 has been internalized into endosomes. This suggests that SOCS2 binds to EphA2 in the context of endosomal membranes. We also found that SOCS2 overexpression decreases steady state levels of EphA2, consistent with increased EphA2 degradation. This effect is indirect: SOCS2 induces EfnA1 expression, and EfnA1 induces EphA2 down-regulation. Other RTKs have been reported to bind, and be regulated by, over-expressed SOCS proteins. Our data suggest that SOCS protein over-expression may regulate receptor tyrosine kinases through indirect and direct mechanisms.