-
BMC Molecular and Cell Biology Jun 2023Janus kinase 3 (JAK3) is a member of the JAK family of tyrosine kinase proteins involved in cytokine receptor-mediated intracellular signal transduction through the...
Janus kinase 3 (JAK3) is a member of the JAK family of tyrosine kinase proteins involved in cytokine receptor-mediated intracellular signal transduction through the JAK/STAT signaling pathway. JAK3 was previously shown as differentially expressed in granulosa cells (GC) of bovine pre-ovulatory follicles suggesting that JAK3 could modulate GC function and activation/inhibition of downstream targets. We used JANEX-1, a JAK3 inhibitor, and FSH treatments and analyzed proliferation markers, steroidogenic enzymes and phosphorylation of target proteins including STAT3, CDKN1B/p27 and MAPK8IP3/JIP3. Cultured GC were treated with or without FSH in the presence or not of JANEX-1. Expression of steroidogenic enzyme CYP11A1, but not CYP19A1, was upregulated in GC treated with FSH and both were significantly decreased when JAK3 was inhibited. Proliferation markers CCND2 and PCNA were reduced in JANEX-1-treated GC and upregulated by FSH. Western blots analyses showed that JANEX-1 treatment reduced pSTAT3 amounts while JAK3 overexpression increased pSTAT3. Similarly, FSH treatment increased pSTAT3 even in JANEX-1-treated GC. UHPLC-MS/MS analyses revealed phosphorylation of specific amino acid residues within JAK3 as well as CDKN1B and MAPK8IP3 suggesting possible activation or inhibition post-FSH or JANEX-1 treatments. We show that FSH activates JAK3 in GC, which could phosphorylate target proteins and likely modulate other signaling pathways involving CDKN1B and MAPK8IP3, therefore controlling GC proliferation and steroidogenic activity.
Topics: Animals; Cattle; Female; Follicle Stimulating Hormone; Granulosa Cells; Janus Kinase 3; Janus Kinases; Phosphorylation; Signal Transduction; STAT Transcription Factors; Tandem Mass Spectrometry
PubMed: 37337185
DOI: 10.1186/s12860-023-00482-5 -
Inflammation Research : Official... Jun 2023The discovery of new inflammatory pathways and the mechanism of action of inflammatory, autoimmune, genetic, and neoplastic diseases led to the development of... (Review)
Review
OBJECTIVE AND DESIGN
The discovery of new inflammatory pathways and the mechanism of action of inflammatory, autoimmune, genetic, and neoplastic diseases led to the development of immunologically driven drugs. We aimed to perform a narrative review regarding the rising of a new class of drugs capable of blocking important and specific intracellular signals in the maintenance of these pathologies: the small molecules.
MATERIALS/METHODS
A total of 114 scientific papers were enrolled in this narrative review.
RESULTS
We describe in detail the families of protein kinases-Janus Kinase (JAK), Src kinase, Syk tyrosine kinase, Mitogen-Activated Protein Kinase (MAPK), and Bruton Tyrosine Kinase (BTK)-their physiologic function and new drugs that block these pathways of intracellular signaling. We also detail the involved cytokines and the main metabolic and clinical implications of these new medications in the field of dermatology.
CONCLUSIONS
Despite having lower specificity compared to specific immunobiological therapies, these new drugs are effective in a wide variety of dermatological diseases, especially diseases that had few therapeutic options, such as psoriasis, psoriatic arthritis, atopic dermatitis, alopecia areata, and vitiligo.
Topics: Humans; Dermatology; Autoimmunity; Psoriasis; Inflammation; Vitiligo; Janus Kinases
PubMed: 37212867
DOI: 10.1007/s00011-023-01744-w -
Biology of Blood and Marrow... Jun 2018For patients with hematologic malignancies, allogeneic hematopoietic cell transplantation (alloHCT) offers a potential curative treatment option, primarily due to an... (Review)
Review
For patients with hematologic malignancies, allogeneic hematopoietic cell transplantation (alloHCT) offers a potential curative treatment option, primarily due to an allogeneic immune response against recipient tumor cells (ie, graft-versus-leukemia [GVL] activity). However, many recipients of alloHCT develop graft-versus-host disease (GVHD), in which allogeneic immune responses lead to the damage of healthy tissue. GVHD is a leading cause of nonrelapse mortality and a key contributor to morbidity among patients undergoing alloHCT. Therefore, improving alloHCT outcomes will require treatment strategies that prevent or mitigate GVHD without disrupting GVL activity. Janus kinases (JAKs) are intracellular signaling molecules that are well positioned to regulate GVHD. A variety of cytokines that signal through the JAK signaling pathways play a role in regulating the development, proliferation, and activation of several immune cell types important for GVHD pathogenesis, including dendritic cells, macrophages, T cells, B cells, and neutrophils. Importantly, despite JAK regulation of GVHD, preclinical evidence suggests that JAK inhibition preserves GVL activity. Here we provide an overview of potential roles for JAK signaling in the pathogenesis of acute and chronic GVHD as well as effects on GVL activity. We also review preclinical and clinical results with JAK inhibitors in acute and chronic GVHD settings, with added focus on those actively being evaluated in patients with acute and chronic GVHD.
Topics: Graft vs Host Disease; Graft vs Leukemia Effect; Hematopoietic Stem Cell Transplantation; Humans; Janus Kinases; Signal Transduction; Transplantation, Homologous
PubMed: 29289756
DOI: 10.1016/j.bbmt.2017.12.797 -
PLoS Pathogens Nov 2023Human herpesvirus 8 (HHV-8) encodes four viral interferon regulatory factors (vIRFs) that target cellular IRFs and/or other innate-immune and stress signaling regulators...
Human herpesvirus 8 (HHV-8) encodes four viral interferon regulatory factors (vIRFs) that target cellular IRFs and/or other innate-immune and stress signaling regulators and suppress the cellular response to viral infection and replication. For vIRF-1, cellular protein targets include IRFs, p53, p53-activating ATM kinase, BH3-only proteins, and antiviral signaling effectors MAVS and STING; vIRF-1 inhibits each, with demonstrated or likely promotion of HHV-8 de novo infection and productive replication. Here, we identify direct interactions of vIRF-1 with STAT3 and STAT-activating Janus kinase TYK2 (the latter reported previously by us to be inhibited by vIRF-1) and suppression by vIRF-1 of cytokine-induced STAT3 activation. Suppression of active, phosphorylated STAT3 (pSTAT3) by vIRF-1 was evident in transfected cells and vIRF-1 ablation in lytically-reactivated recombinant-HHV-8-infected cells led to increased levels of pSTAT3. Using a panel of vIRF-1 deletion variants, regions of vIRF-1 required for interactions with STAT3 and TYK2 were identified, which enabled correlation of STAT3 signaling inhibition by vIRF-1 with TYK2 binding, independently of STAT3 interaction. A viral mutant expressing vIRF-1 deletion-variant Δ198-222 refractory for TYK2 interaction and pSTAT3 suppression was severely compromised for productive replication. Conversely, expression of phosphatase-resistant, protractedly-active STAT3 led to impaired HHV-8 replication. Cells infected with HHV-8 mutants expressing STAT3-refractory vIRF-1 deletion variants or depleted of STAT3 displayed reduced vIRF-1 expression, while custom-peptide-promoted STAT3 interaction could effect increased vIRF-1 expression and enhanced virus replication. Taken together, our data identify vIRF-1 targeting and inhibition of TYK2 as a mechanism of STAT3-signaling suppression and critical for HHV-8 productive replication, the importance of specific pSTAT3 levels for replication, positive roles of STAT3 and vIRF-1-STAT3 interaction in vIRF-1 expression, and significant contributions to lytic replication of STAT3 targeting by vIRF-1.
Topics: Humans; Herpesvirus 8, Human; Interferon Regulatory Factor-1; Janus Kinases; STAT3 Transcription Factor; Tumor Suppressor Protein p53; TYK2 Kinase; Host-Pathogen Interactions
PubMed: 37983265
DOI: 10.1371/journal.ppat.1011806 -
Missouri Medicine 2023A number of chronic skin diseases, such as vitiligo and alopecia areata, are historically resistant to or respond poorly to treatment. Additionally, disorders such as... (Review)
Review
A number of chronic skin diseases, such as vitiligo and alopecia areata, are historically resistant to or respond poorly to treatment. Additionally, disorders such as atopic dermatitis and psoriasis have subtypes that are inadequately treated by current medications. Lastly, in the field of dermatology there are a number of conditions, some genetic (such as Darier's disease and Hailey-Hailey disease) and others caused by aberrant inflammatory responses (macrophage-driven conditions such as sarcoidosis and autoimmune conditions such as localized scleroderma) where effective treatments have been limited to date. A new class of anti-inflammatory medications that inhibit the Janus Kinase-Signal transducer and activator of transcription pathway (JAK-STAT) show great promise in providing new and effective treatment of these formerly recalcitrant conditions. This brief review will cover inhibitors of the JAK-STAT pathway (JAK inhibitors) currently approved for use in treating dermatologic diseases including several very recently approved medications. It will also touch on additional conditions under study or where early reports of efficacy are promising.
Topics: Humans; Janus Kinase Inhibitors; Janus Kinases; STAT Transcription Factors; Signal Transduction; Skin Care
PubMed: 36860609
DOI: No ID Found -
Prague Medical Report 2023Alopecia areata is a disease of autoimmune origin which causes non scarring hair loss. The extent of alopecia varies from a small patch to complete scalp and body hair... (Review)
Review
Alopecia areata is a disease of autoimmune origin which causes non scarring hair loss. The extent of alopecia varies from a small patch to complete scalp and body hair loss, which can have huge psychosocial impact for those affected. Treatment modalities which have been used so far included nonspecific immunosuppressive medications, such as corticosteroids, cyclosporine, and methotrexate, or topical immunomodulators, such as diphencyprone, dithranol, and squaric acid dibutylester. The recognition of the importance of Janus kinase pathway in alopecia areata pathogenesis enabled more specific approaches in treatment. Positive outcomes of Janus kinase inhibitors in several trials granted approval for baricitinib which became the first on-label treatment for alopecia areata. The aim of this review is to summarize the role, efficacy and safety of several Janus kinase inhibitors in alopecia areata.
Topics: Humans; Alopecia Areata; Janus Kinase Inhibitors; Janus Kinases; Adjuvants, Immunologic
PubMed: 36763827
DOI: 10.14712/23362936.2023.1 -
Biomolecules Nov 2023Colorectal cancer is a known complication of chronic inflammation of the colon ("colitis-associated colon cancer"). Inflammatory bowel disease (IBD) is a chronic... (Review)
Review
Colorectal cancer is a known complication of chronic inflammation of the colon ("colitis-associated colon cancer"). Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract. Patients with IBD are at increased risk of colon cancer compared to the general population. Kinase signaling pathways play critical roles in both the inflammation and regulating cellular processes such as proliferation and survival that contribute to cancer development. Here we review the interplay of kinase signaling pathways (mitogen-activated protein kinases, cyclin-dependent kinases, autophagy-activated kinases, JAK-STAT, and other kinases) and their effects on colitis-associated colon cancer. We also discuss the role of JAK-STAT signaling in the pathogenesis of IBD and the therapeutic landscape of JAK inhibitors for the treatment of IBD.
Topics: Humans; Colitis-Associated Neoplasms; Inflammatory Bowel Diseases; Janus Kinases; Inflammation
PubMed: 38002302
DOI: 10.3390/biom13111620 -
Blood Apr 2010Constitutive JAK2 activation in hematopoietic cells by the JAK2V617F mutation recapitulates myeloproliferative neoplasm (MPN) phenotypes in mice, establishing JAK2...
Constitutive JAK2 activation in hematopoietic cells by the JAK2V617F mutation recapitulates myeloproliferative neoplasm (MPN) phenotypes in mice, establishing JAK2 inhibition as a potential therapeutic strategy. Although most polycythemia vera patients carry the JAK2V617F mutation, half of those with essential thrombocythemia or primary myelofibrosis do not, suggesting alternative mechanisms for constitutive JAK-STAT signaling in MPNs. Most patients with primary myelofibrosis have elevated levels of JAK-dependent proinflammatory cytokines (eg, interleukin-6) consistent with our observation of JAK1 hyperactivation. Accordingly, we evaluated the effectiveness of selective JAK1/2 inhibition in experimental models relevant to MPNs and report on the effects of INCB018424, the first potent, selective, oral JAK1/JAK2 inhibitor to enter the clinic. INCB018424 inhibited interleukin-6 signaling (50% inhibitory concentration [IC(50)] = 281nM), and proliferation of JAK2V617F(+) Ba/F3 cells (IC(50) = 127nM). In primary cultures, INCB018424 preferentially suppressed erythroid progenitor colony formation from JAK2V617F(+) polycythemia vera patients (IC(50) = 67nM) versus healthy donors (IC(50) > 400nM). In a mouse model of JAK2V617F(+) MPN, oral INCB018424 markedly reduced splenomegaly and circulating levels of inflammatory cytokines, and preferentially eliminated neoplastic cells, resulting in significantly prolonged survival without myelosuppressive or immunosuppressive effects. Preliminary clinical results support these preclinical data and establish INCB018424 as a promising oral agent for the treatment of MPNs.
Topics: Amino Acid Substitution; Animals; Apoptosis; Blood Cell Count; Cell Proliferation; Cell Survival; Colony-Forming Units Assay; Cytokines; Disease Models, Animal; Drug Screening Assays, Antitumor; Hematopoietic Stem Cells; Humans; Janus Kinase 1; Janus Kinase 2; Janus Kinases; Mice; Myeloproliferative Disorders; Nitriles; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; Signal Transduction; Spleen; Treatment Outcome
PubMed: 20130243
DOI: 10.1182/blood-2009-04-214957 -
Trends in Microbiology Jul 2017Interferon-stimulated genes (ISGs) are a group of gene products that coordinately combat pathogen invasions, in particular viral infections. Transcription of ISGs occurs... (Review)
Review
Interferon-stimulated genes (ISGs) are a group of gene products that coordinately combat pathogen invasions, in particular viral infections. Transcription of ISGs occurs rapidly upon pathogen invasion, and this is classically provoked via activation of the Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway, mainly by interferons (IFNs). However, a plethora of recent studies have reported a variety of non-canonical mechanisms regulating ISG transcription. These new studies are extremely important for understanding the quantitative and temporal differences in ISG transcription under specific circumstances. Because these canonical and non-canonical regulatory mechanisms are essential for defining the nature of host defense and associated detrimental proinflammatory effects, we comprehensively review the state of this rapidly evolving field and the clinical implications of recently acquired knowledge in this respect.
Topics: Antiviral Agents; Gene Expression Regulation; Host-Pathogen Interactions; Humans; Immunity; Interferons; Janus Kinases; Phosphorylation; Signal Transduction; Transcription, Genetic
PubMed: 28139375
DOI: 10.1016/j.tim.2017.01.001 -
Biomedicine & Pharmacotherapy =... Nov 2023Tyrosine kinase 2 (TYK2) as a member of Janus kinase (JAK) family, mainly mediates the signaling of type I interferons (IFN), interleukin-12 (IL-12) and interleukin-23...
Tyrosine kinase 2 (TYK2) as a member of Janus kinase (JAK) family, mainly mediates the signaling of type I interferons (IFN), interleukin-12 (IL-12) and interleukin-23 (IL-23), which has become an attractive target for treatment of immune and inflammatory diseases. However, the development of selective TYK2 inhibitors is challenging due to the high homology of the catalytic kinase domain among the JAK family members. Here, we report a novel and potent allosteric inhibitor, WD-890, which binds to the pseudokinase domain of TYK2 with high selectivity and inhibits its function. We accomplished a series of preclinical studies to demonstrate the therapeutic efficacy of WD-890 in four animal models: systemic lupus erythematosus (SLE), psoriasis, psoriatic arthritis (PsA), and inflammatory bowel disease (IBD). The pharmacokinetic and toxicology results further indicate that WD-890 has favorable absorption, distribution, metabolism, and excretion (ADME) properties and tolerable toxicity. In conclusion, our study shows that WD-890 could be a promising oral TYK2 inhibitor for future treatment of autoimmune diseases.
Topics: Animals; TYK2 Kinase; Arthritis, Psoriatic; Autoimmune Diseases; Janus Kinases; Interleukin-12
PubMed: 37778274
DOI: 10.1016/j.biopha.2023.115611