Targeting the Interleukin-6/Jak/Stat Pathway in Human Malignancies

The Janus kinase/signal transducer and activator of transcription (Jak/Stat) pathway was discovered 20 years ago as a mediator of cytokine signaling. Since this time, more than 2,500 articles have been published demonstrating the importance of this pathway in virtually all malignancies. Although there are dozens of cytokines and cytokine receptors, four Jaks, and seven Stats, it seems that interleukin-6–mediated activation of Stat3 is a principal pathway implicated in promoting tumorigenesis. This transcription factor regulates the expression of numerous critical mediators of tumor formation and metastatic progression. This review will examine the relative importance and function of this pathway in nonmalignant conditions as well as malignancies (including tumor intrinsic and extrinsic), the influence of other Stats, the development of inhibitors to this pathway, and the potential role of inhibitors in controlling or eradicating cancers.

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Interleukin-6 Induces Myogenic Differentiation via JAK2-STAT3 Signaling in Mouse C2C12 Myoblast Cell Line and Primary Human Myoblasts

International Journal of Molecular Sciences ◽

10.3390/ijms20215273 ◽

2019 ◽

Vol 20 (21) ◽

pp. 5273 ◽

Cited By ~ 8

Author(s):

Paul J. Steyn ◽

Kevin Dzobo ◽

Robert I. Smith ◽

Kathryn H. Myburgh

Keyword(s):

Cell Cycle ◽

Protein Expression ◽

Cell Line ◽

Interleukin 6 ◽

Janus Kinase ◽

Cytokine Signaling ◽

C2c12 Myoblast ◽

Myoblast Cell Line ◽

Myoblast Cell ◽

Stat Pathway

Postnatal muscle growth and exercise- or injury-induced regeneration are facilitated by myoblasts. Myoblasts respond to a variety of proteins such as cytokines that activate various signaling cascades. Cytokines belonging to the interleukin 6 superfamily (IL-6) influence myoblasts’ proliferation but their effect on differentiation is still being researched. The Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway is one of the key signaling pathways identified to be activated by IL-6. The aim of this study was to investigate myoblast fate as well as activation of JAK-STAT pathway at different physiologically relevant IL-6 concentrations (10 pg/mL; 100 pg/mL; 10 ng/mL) in the C2C12 mouse myoblast cell line and primary human myoblasts, isolated from eight young healthy male volunteers. Myoblasts’ cell cycle progression, proliferation and differentiation in vitro were assessed. Low IL-6 concentrations facilitated cell cycle transition from the quiescence/Gap1 (G0/G1) to the synthesis (S-) phases. Low and medium IL-6 concentrations decreased the expression of myoblast determination protein 1 (MyoD) and myogenin and increased proliferating cell nuclear antigen (PCNA) expression. In contrast, high IL-6 concentration shifted a larger proportion of cells to the pro-differentiation G0/G1 phase of the cell cycle, substantiated by significant increases of both MyoD and myogenin expression and decreased PCNA expression. Low IL-6 concentration was responsible for prolonged JAK1 activation and increased suppressor of cytokine signaling 1 (SOCS1) protein expression. JAK-STAT inhibition abrogated IL-6-mediated C2C12 cell proliferation. In contrast, high IL-6 initially increased JAK1 activation but resulted in prolonged JAK2 activation and elevated SOCS3 protein expression. High IL-6 concentration decreased interleukin-6 receptor (IL-6R) expression 24 h after treatment whilst low IL-6 concentration increased IL-6 receptor (IL-6R) expression at the same time point. In conclusion, this study demonstrated that IL-6 has concentration- and time-dependent effects on both C2C12 mouse myoblasts and primary human myoblasts. Low IL-6 concentration induces proliferation whilst high IL-6 concentration induces differentiation. These effects are mediated by specific components of the JAK/STAT/SOCS pathway.

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Role of the JAK-STAT Pathway in Bovine Mastitis and Milk Production

Animals ◽

10.3390/ani10112107 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2107

Author(s):

Muhammad Zahoor Khan ◽

Adnan Khan ◽

Jianxin Xiao ◽

Yulin Ma ◽

Jiaying Ma ◽

...

Keyword(s):

Dairy Cattle ◽

Milk Production ◽

Critical Role ◽

Bovine Mastitis ◽

Janus Kinase ◽

Cytokine Signaling ◽

Signal Transducer ◽

Production Traits ◽

Stat Pathway

The cytokine-activated Janus kinase (JAK)—signal transducer and activator of transcription (STAT) pathway is a sequence of communications between proteins in a cell, and it is associated with various processes such as cell division, apoptosis, mammary gland development, lactation, anti-inflammation, and immunity. The pathway is involved in transferring information from receptors on the cell surface to the cell nucleus, resulting in the regulation of genes through transcription. The Janus kinase 2 (JAK2), signal transducer and activator of transcription A and B (STAT5 A & B), STAT1, and cytokine signaling suppressor 3 (SOCS3) are the key members of the JAK-STAT pathway. Interestingly, prolactin (Prl) also uses the JAK-STAT pathway to regulate milk production traits in dairy cattle. The activation of JAK2 and STATs genes has a critical role in milk production and mastitis resistance. The upregulation of SOCS3 in bovine mammary epithelial cells inhibits the activation of JAK2 and STATs genes, which promotes mastitis development and reduces the lactational performance of dairy cattle. In the current review, we highlight the recent development in the knowledge of JAK-STAT, which will enhance our ability to devise therapeutic strategies for bovine mastitis control. Furthermore, the review also explores the role of the JAK-STAT pathway in the regulation of milk production in dairy cattle.

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POPDC proteins and cardiac function

Biochemical Society Transactions ◽

10.1042/bst20190249 ◽

2019 ◽

Vol 47 (5) ◽

pp. 1393-1404 ◽

Cited By ~ 4

Author(s):

Thomas Brand

Keyword(s):

Potential Role ◽

Striated Muscle ◽

Short Review ◽

Effector Proteins ◽

Muscle Disease ◽

Disease Genes ◽

Protein Protein Interaction ◽

Interaction Partners ◽

And Function

Abstract The Popeye domain-containing gene family encodes a novel class of cAMP effector proteins in striated muscle tissue. In this short review, we first introduce the protein family and discuss their structure and function with an emphasis on their role in cyclic AMP signalling. Another focus of this review is the recently discovered role of POPDC genes as striated muscle disease genes, which have been associated with cardiac arrhythmia and muscular dystrophy. The pathological phenotypes observed in patients will be compared with phenotypes present in null and knockin mutations in zebrafish and mouse. A number of protein–protein interaction partners have been discovered and the potential role of POPDC proteins to control the subcellular localization and function of these interacting proteins will be discussed. Finally, we outline several areas, where research is urgently needed.

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Ultraviolet Radiation and Chronic Inflammation—Molecules and Mechanisms Involved in Skin Carcinogenesis: A Narrative Review

Life ◽

10.3390/life11040326 ◽

2021 ◽

Vol 11 (4) ◽

pp. 326

Author(s):

Magdalena Ciążyńska ◽

Irmina Olejniczak-Staruch ◽

Dorota Sobolewska-Sztychny ◽

Joanna Narbutt ◽

Małgorzata Skibińska ◽

...

Keyword(s):

Ultraviolet Radiation ◽

Chronic Inflammation ◽

Potential Role ◽

Tumor Formation ◽

Skin Carcinogenesis ◽

Molecular Networks ◽

Cancer Therapies ◽

Inflammatory Microenvironment ◽

Skin Cancers

The process of skin carcinogenesis is still not fully understood. Both experimental and epidemiological evidence indicate that chronic inflammation is one of the hallmarks of microenvironmental-agent-mediated skin cancers and contributes to its development. Maintaining an inflammatory microenvironment is a condition leading to tumor formation. Multiple studies focus on the molecular pathways activating tumorigenesis by inflammation and indicate several biomarkers and factors that can improve diagnostic and prognostic processes in oncology and dermatology. Reactive oxygen species produced by ultraviolet radiation, oxidizers, or metabolic processes can damage cells and initiate pro-inflammatory cascades. Considering the potential role of inflammation in cancer development and metastasis, the identification of early mechanisms involved in carcinogenesis is crucial for clinical practice and scientific research. Moreover, it could lead to the progress of advanced skin cancer therapies. We focus on a comprehensive analysis of available evidence and on understanding how chronic inflammation and ultraviolet radiation can result in skin carcinogenesis. We present the inflammatory environment as complex molecular networks triggering tumorigenesis and constituting therapeutic targets.

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Tofacitinib Suppresses Several JAK-STAT Pathways in Rheumatoid Arthritis In Vivo and Baseline Signaling Profile Associates With Treatment Response

Frontiers in Immunology ◽

10.3389/fimmu.2021.738481 ◽

2021 ◽

Vol 12 ◽

Author(s):

Maaria Palmroth ◽

Krista Kuuliala ◽

Ritva Peltomaa ◽

Anniina Virtanen ◽

Antti Kuuliala ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

T Cells ◽

Treatment Response ◽

Peripheral Blood ◽

Janus Kinase ◽

Cytokine Signaling ◽

Stat3 Phosphorylation ◽

Stat Pathway

ObjectiveCurrent knowledge on the actions of tofacitinib on cytokine signaling pathways in rheumatoid arthritis (RA) is based on in vitro studies. Our study is the first to examine the effects of tofacitinib treatment on Janus kinase (JAK) - signal transducer and activator of transcription (STAT) pathways in vivo in patients with RA.MethodsSixteen patients with active RA, despite treatment with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), received tofacitinib 5 mg twice daily for three months. Levels of constitutive and cytokine-induced phosphorylated STATs in peripheral blood monocytes, T cells and B cells were measured by flow cytometry at baseline and three-month visits. mRNA expression of JAKs, STATs and suppressors of cytokine signaling (SOCS) were measured from peripheral blood mononuclear cells (PBMCs) by quantitative PCR. Association of baseline signaling profile with treatment response was also investigated.ResultsTofacitinib, in csDMARDs background, decreased median disease activity score (DAS28) from 4.4 to 2.6 (p < 0.001). Tofacitinib treatment significantly decreased cytokine-induced phosphorylation of all JAK-STAT pathways studied. However, the magnitude of the inhibitory effect depended on the cytokine and cell type studied, varying from 10% to 73% inhibition following 3-month treatment with tofacitinib. In general, strongest inhibition by tofacitinib was observed with STAT phosphorylations induced by cytokines signaling through the common-γ-chain cytokine receptor in T cells, while lowest inhibition was demonstrated for IL-10 -induced STAT3 phosphorylation in monocytes. Constitutive STAT1, STAT3, STAT4 and STAT5 phosphorylation in monocytes and/or T cells was also downregulated by tofacitinib. Tofacitinib treatment downregulated the expression of several JAK-STAT pathway components in PBMCs, SOCSs showing the strongest downregulation. Baseline STAT phosphorylation levels in T cells and monocytes and SOCS3 expression in PBMCs correlated with treatment response.ConclusionsTofacitinib suppresses multiple JAK-STAT pathways in cytokine and cell population specific manner in RA patients in vivo. Besides directly inhibiting JAK activation, tofacitinib downregulates the expression of JAK-STAT pathway components. This may modulate the effects of tofacitinib on JAK-STAT pathway activation in vivo and explain some of the differential findings between the current study and previous in vitro studies. Finally, baseline immunological markers associate with the treatment response to tofacitinib.

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SOCS1/SOCS3 Immune Axis Modulates Synthetic Perturbations in IL6 Biological Circuit for Dynamical Cellular Response

10.1101/2020.08.31.276634 ◽

2020 ◽

Author(s):

Bhavnita Soni ◽

Shailza Singh

Keyword(s):

Signaling Pathway ◽

Cellular Response ◽

Inflammatory Cytokine ◽

Cytokine Expression ◽

Janus Kinase ◽

Cytokine Signaling ◽

Macrophage Phenotype ◽

Regulatory Circuit ◽

Stat Pathway

AbstractMacrophage phenotype plays a crucial role in the pathogenesis of Leishmanial infection. Pro-inflammatory cytokines are the key regulators that eliminate the infection induced by Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. Suppressor of cytokine signaling (SOCS) is a well-known negative feedback regulator of JAK/STAT pathway. However, change in expression levels of SOCS in correlation with the establishment of infection is not well understood. Mathematical modeling of IL6 signaling pathway have helped identified the role of SOCS1 in establishment of infection. Furthermore, the ratio of SOCS1 and SOCS3 has been quantified both in silico as well as in vitro, indicating an immune axis which governs the macrophage phenotype during L. major infection. The ability of SOCS1 protein to inhibit the JAK/STAT1 signaling pathway and thereby decreasing pro-inflammatory cytokine expression makes it a strong candidate for therapeutic intervention. Using synthetic biology approaches, peptide based immuno-regulatory circuit have been designed to target the activity of SOCS1 which can restore pro-inflammatory cytokine expression during infection.

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Management of refractory cutaneous dermatomyositis: potential role of Janus kinase inhibition with tofacitinib

Rheumatology ◽

10.1093/rheumatology/key366 ◽

2019 ◽

Vol 58 (6) ◽

pp. 1011-1015 ◽

Cited By ~ 23

Author(s):

Siamak Moghadam-Kia ◽

Devon Charlton ◽

Rohit Aggarwal ◽

Chester V Oddis

Keyword(s):

Potential Role ◽

Janus Kinase ◽

Kinase Inhibition ◽

Janus Kinase Inhibition

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Suppressor of cytokine signaling 2 (SOCS2) deletion protects against multiple low dose streptozotocin-induced type 1 diabetes in adult male mice

Hormone Molecular Biology and Clinical Investigation ◽

10.1515/hmbci-2015-0036 ◽

2016 ◽

Vol 26 (1) ◽

Cited By ~ 5

Author(s):

Amira Alkharusi ◽

Mercedes Mirecki-Garrido ◽

Zuheng Ma ◽

Fahad Zadjali ◽

Amilcar Flores-Morales ◽

...

Keyword(s):

Type I Diabetes ◽

Janus Kinase ◽

Cytokine Signaling ◽

Type I ◽

Suppressor Of Cytokine Signaling ◽

Β Cell ◽

Diabetes In Mice ◽

Socs Proteins ◽

Stat Pathway

AbstractDiabetes type 1 is characterized by the failure of beta cells to produce insulin. Suppressor of cytokine signaling (SOCS) proteins are important regulators of the Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway. Previous studies have shown that GH can prevent the development of type I diabetes in mice and that SOCS2 deficiency mimics a state of increased GH sensitivity.The elevated sensitivity of SOCS2We show that 6-month-old SOCS2Knockdown of SOCS2 makes mice less sensitive to MLDSTZ. These results are consistent with the proposal that elimination of SOCS2 in pancreatic islets creates a state of β-cell hypersensitivity to GH/PRL that mimics events in pregnancy, and which is protective against MLDSTZ-induced type I diabetes in mice. SOCS2-dependent control of β-cell survival may be of relevance to islet regeneration and survival in transplantation.

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miR-221 and miR-155 regulate human dendritic cell development, apoptosis, and IL-12 production through targeting of p27kip1, KPC1, and SOCS-1

Blood ◽

10.1182/blood-2010-12-322503 ◽

2011 ◽

Vol 117 (16) ◽

pp. 4293-4303 ◽

Cited By ~ 182

Author(s):

Changming Lu ◽

Xin Huang ◽

Xiaoxiao Zhang ◽

Kristin Roensch ◽

Qing Cao ◽

...

Keyword(s):

Cytokine Signaling ◽

Wild Type ◽

Suppressor Of Cytokine Signaling ◽

Hematopoietic Progenitor ◽

Monocyte Differentiation ◽

P27kip1 Protein ◽

And Function ◽

Antigen Presenting ◽

Dc Maturation

Abstract Dendritic cells (DCs) are potent antigen-presenting cells derived from hematopoietic progenitor cells and circulating monocytes. To investigate the role of microRNAs (miRNAs) during DC differentiation, maturation, and function, we profiled miRNA expression in human monocytes, immature DCs (imDCs), and mature DCs (mDCs). Stage-specific, differential expression of 27 miRNAs was found during monocyte differentiation into imDCs and mDCs. Among them, decreased miR-221 and increased miR-155 expression correlated with p27kip1 accumulation in DCs. Silencing of miR-221 or overexpressing of miR-155 in DCs resulted in p27kip1 protein increase and DC apoptosis. Moreover, mDCs from miR-155−/− mice were less apoptotic than those from wild-type mice. Silencing of miR-155 expression had little effect on DC maturation but reduced IL-12p70 production, whereas miR-155 overexpression in mDCs enhanced IL-12p70 production. Kip1 ubiquitination-promoting complex 1, suppressor of cytokine signaling 1, and CD115 (M-CSFR) were functional targets of miR-155. Furthermore, we provide evidence that miR-155 indirectly regulated p27kip1 protein level by targeting Kip1 ubiquitination-promoting complex 1. Thus, our study uncovered miRNA signatures during monocyte differentiation into DCs and the new regulatory role of miR-221 and miR-155 in DC apoptosis and IL-12p70 production.

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Endocrine Significance of SARS-CoV-2’s Reliance on ACE2

Endocrinology ◽

10.1210/endocr/bqaa108 ◽

2020 ◽

Vol 161 (9) ◽

Cited By ~ 7

Author(s):

Eric Lazartigues ◽

Mirza Muhammad Fahd Qadir ◽

Franck Mauvais-Jarvis

Keyword(s):

Potential Role ◽

Renin Angiotensin System ◽

Converting Enzyme ◽

Angiotensin System ◽

Angiotensin Converting Enzyme 2 ◽

Global Impact ◽

The Past ◽

And Function ◽

Endocrine Tissues

Abstract The current COVID-19 pandemic is the most disruptive event in the past 50 years, with a global impact on health care and world economies. It is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a coronavirus that uses angiotensin-converting enzyme 2 (ACE2) as an entry point to the cells. ACE2 is a transmembrane carboxypeptidase and member of the renin-angiotensin system. This mini-review summarizes the main findings regarding ACE2 expression and function in endocrine tissues. We discuss rapidly evolving knowledge on the potential role of ACE2 and SARS coronaviruses in endocrinology and the development of diabetes mellitus, hypogonadism, and pituitary and thyroid diseases.

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