miR-136 Suppresses the Aggressive Proliferation of Non-Small Cell Lung Cancer Through Restraining Histone Deacetylase 1 (HDAC1) and Phosphorylation of the Janus Kinase 2/Signal Transducer and Activator of Transcription 3 (Jak2/STAT3) Pathway

microRNA-136 can inhibit the proliferating activity of malignant cells and also participate in chemotherapy resistance of colorectal cancer via modulating HDAC1. This study assessed miR-136’s effect on NSCLC cell proliferation and underlying mechanisms. Tumor tissues and paracancerous tissues from NSCLC patients were collected to measure miR-136 and HDAC1 level. Cells were transfected with miR-136-mimics, miR-136-inhibitors or miR-136 mimics+HDAC1-OE followed by analysis of cell viability and apoptosis by CCK-8 method and flow cytometry, phosphorylation of Jak2/STAT3 by western blot. miR-136 was significantly downregulated in tumor tissues and NSCLC cells, accompanied by upregulated HDAC1. miR-136 overexpression suppressed HDAC1 expression, retarded phosphorylation and activation of Jak2/STAT3 signaling, reduced NSCLC cell viability and enhanced apoptosis. In addition, co-transfection of miR-136-mimics and HDAC1-OE reversed the inhibitory effects of miR-136 on NSCLC cells. In conclusion, miR-136 is reduced and HDAC1 is increased in NSCLC and miR-136 overexpression inhibited NSCLC cell proliferation and increased apoptosis possibly through regulating HDAC1/Jak2/STAT3 signal pathway, indicating that miR-136 might be a novel target for the treatment of NSCLC.

Oxidative Stress in Intestinal Ischemia-Reperfusion

Ischemia-reperfusion (I/R) injury is a manifestation of tissue or organ damage that is followed by ischemia and exacerbated by the return of blood flow to a previously damaged tissue or organ. The intestines are one of the most sensitive tissues and organs to I/R injury. Moreover, the adverse consequences of intestinal I/R (II/R) injury are not limited to the intestine itself and can also lead to damage of the distant tissues and organs. The mechanism of II/R is extremely complex and oxidative stress is the key link in the pathogenesis of II/R injury. This study summarizes the roles of oxidative stress and its signaling pathways involved in II/R. The signaling pathways that mitigate II/R injury include the nuclear factor erythroid-related factor 2 (Nrf2)-mediated signaling pathway, Wnt/β-catenin pathway, and phosphatidylinositol kinase 3 (PI3K)/Akt pathway; those that aggravate II/R injury include the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, Toll-like receptor (TLR) receptor-mediated signaling pathway, protein kinase CβII (PKCβII)/p66shc pathway, and microRNA (miRNA)/p66shc pathway; the effect of miRNA on related pathways and mitochondrial DNA translocation. The aforementioned pathways provide new ideas for further exploring the occurrence and development of II/R and more effective treatments for II/R injury.

Effectiveness of Baricitinib in Refractory Seronegative Rheumatoid Arthritis and Uveitis: A Case Report

Baricitinib is a Janus kinase (JAK) inhibitor used to treat refractory rheumatoid arthritis and blocks the subtypes JAK1 and JAK2. A 35-year-old man with seronegative rheumatoid arthritis complicated by bilateral severe non-granulomatous panuveitis was resistant to steroid treatment, multiple conventional disease-modifying antirheumatic drugs (methotrexate and salazosulfapyridine), and TNF-α inhibitors (adalimumab and infliximab). Therefore, the TNF-α inhibitors were switched to baricitinib to decrease the activity of systemic arthritis. Along with the amelioration of inflammatory activity in seronegative rheumatoid arthritis, the inflammatory activity of uveitis was decreased. Vitreous opacity, serous retinal detachment, and anterior chamber cells showed improvement. Baricitinib was effective not only in refractory systemic arthritis but also in uveitis, which may provide a new treatment option for patients with refractory uveitis.

Rheumatoid arthritis and myasthenia gravis: a case-based review of the therapeutic options

Introduction Myasthenia gravis is an autoimmune disease affecting the neuromuscular junction, often associated with other autoimmune diseases, including rheumatoid arthritis. Patients with rheumatoid arthritis present an increased prevalence of myasthenia gravis compared to the general population. While these two diseases share some therapeutic options, such as glucocorticoids, methotrexate, and rituximab, there are no guidelines for treating concomitant disease. We aim to review the available evidence and to discuss the efficacy and safety of the therapeutic options in patients with rheumatoid arthritis associated with myasthenia gravis. Method We described three patients with rheumatoid arthritis associated with myasthenia gravis and we performed a systematic review of the associated literature. Results A 48-year-old man and two women (48 and 55 years old) with concomitant diagnoses of active rheumatoid arthritis and well-controlled myasthenia gravis are described. They were treated with methotrexate, leflunomide, upadacitinib, and adalimumab. None of them experienced changes in their myasthenic symptoms. We found 9 additional cases from our literature review. Methotrexate, rituximab, upadacitinib, diphenyl sulfone, auranofin, and loxoprofen sodium did not show an impact on the seven patients with previously well-controlled myasthenia. Glucocorticoids, methotrexate, and rituximab proved effective in active myasthenia gravis and arthritis. Conflicting data emerged for Tumor-necrosis factor inhibitors. Conclusions Although the available evidence remains scarce, we consider glucocorticoids, methotrexate, and rituximab as safe and effective options. The role of tumor-necrosis factor inhibitors remains uncertain. Eventually, Janus Kinase inhibitors are a novel interesting option for these patients. Key Points• To date, the only evidence on the treatment of patients with rheumatoid arthritis and concomitant myasthenia gravis derives from case reports.• Based on the review of the available case reports and on the cases we described, we consider glucocorticoids, methotrexate, and rituximab as safe and effective options, while the role of Tumor-necrosis factor inhibitors remains uncertain.• Based on the cases we described, Janus Kinase inhibitors are a novel interesting option for patients with concomitant rheumatoid arthritis and myasthenia gravis.

Sugammadex affects GH/GHR’s signaling transduction on muscle cells by regulating the membrane-localized GHR level

Objectives Sugammadex (also known as bridion) is a modified γ-cyclodextrin, which is a reversal agent for the neuromuscular block. Growth hormone (GH) has an important biological effect on muscle, regulating muscle growth and development. In the current work, we explored the effect of Sugammadex on GH’s bioactivities. Methods Confocal laser scanning microscope (CLSM), flow cytometry, indirect immunofluorescence, Western-blot, and IP-WB were used to explore the effect of Sugammadex on GH’s bioactivities. Results We found that Sugammadex reduced the activity of GH on muscle cells, which down-regulated GH/GHR-mediated intracellular signaling pathway, such as Janus kinase 2 (JAK2) and signal transducers and activators of transcription 5 (STAT5). We further study the potential biological mechanism by which Sugammadex down-regulated GH/GHR-mediated signaling pathway, a series of related experiments were conducted, and found that Sugammadex may inhibit the proliferation of C2C12 cell via regulating the membrane-localized GHR, which may be the underlying mechanism by which Sugammadex suppressed GHR-induced signaling transduction. This work has laid the theoretical and experimental basis for further exploring the relationship between Sugammadex and GH’s activity. Conclusions In conclusion, this study laid a foundation for further study on the relationship between Sugammadex and GH’s activity.

Oncogenic TYK2P760L kinase is effectively targeted by combinatorial TYK2, mTOR and CDK4/6 kinase blockade

Tyrosine kinase 2 (TYK2) is a member of the Janus kinase/signal transducer and activator of transcription pathway, which is central in cytokine signaling. Previously, germline TYK2 mutations have been described in two patients developing de novo T-cell acute lymphoblastic leukemias (T-ALLs) or precursor B-ALLs. The mutations (P760L and G761V) are located within the regulatory pseudokinase domain and lead to constitutive activation of TYK2. We demonstrate the transformation capacity of TYK2P760L in hematopoietic cell systems including primary bone marrow cells. In vivo engraftment of TYK2P760L-expressing cell lines led to development of leukemia. A kinase inhibitor screen uncovered that oncogenic TYK2 acts synergistically with the PI3K/AKT/mTOR and CDK4/6 pathways. Accordingly, the TYK2-specific inhibitor deucravacitinib (BMS986165) reduces cell viability of TYK2P760Ltransformed cell models and ex vivo cultured TYK2P760L-mutated patient-derived xenograft cells most efficiently when combined with mTOR or CDK4/6 inhibitors. Our study thereby pioneers novel treatment options for patients suffering from TYK2-driven acute leukemia.

Inhibition of the JAK/STAT pathway with baricitinib reduces the multiple organ dysfunction caused by hemorrhagic shock in rats

Objective: The aim of this study was to investigate (a) the effects of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway inhibitor (baricitinib) on the multiple organ dysfunction syndrome (MODS) in a rat model of hemorrhagic shock (HS) and (b) whether treatment with baricitinib attenuates the activation of JAK/STAT, NF-κB and NLRP3 caused by HS. Background: Post-traumatic MODS, which is in part due to excessive systemic inflammation, is associated with high morbidity and mortality. The JAK/STAT pathway is a regulator of numerous growth factor and cytokine receptors and, hence, is considered a potential master regulator of many inflammatory signaling processes. However, its role in trauma-hemorrhage is unknown. Methods: An acute HS rat model was performed to determine the effect of baricitinib on MODS. The activation of JAK/STAT, NF-κB and NLRP3 pathways were analyzed by western blotting in the kidney and liver. Results: We demonstrate here for the first time that treatment with baricitinib (during resuscitation following severe hemorrhage) attenuates the organ injury and dysfunction and the activation of JAK/STAT, NF-κB and NLRP3 pathways caused by HS in the rat. Conclusions: Our results point to a role of the JAK/STAT pathway in the pathophysiology of the organ injury and dysfunction caused by trauma/hemorrhage and indicate that JAK inhibitors, such as baricitinib, may be repurposed for the treatment of the MODS after trauma and/or hemorrhage.

Mitigation of Equine Recurrent Uveitis Through Topical Suppressor of Cytokine Signaling-1 Mimetic Peptide: Open Label Safety and Efficacy Pilot Study

Equine recurrent uveitis (ERU) is a painful and debilitating autoimmune disease, and represents the only spontaneous model of human recurrent uveitis (RU). Despite the efficacy of existing treatments, RU remains a leading cause of visual handicap in horses and humans. Cytokines, which utilize Janus kinase 2 (Jak2) for signaling, drive the inflammatory processes in ERU that promote blindness. Notably, suppressor of signaling-1 (SOCS1), which naturally limits the activation of Jak2 through binding interactions, is often deficient in autoimmune disease patients. Significantly, we previously showed that topical administration of a SOCS1 peptide mimic (SOCS1-KIR) mitigated induced rodent uveitis. In this pilot study, we test the potential to translate the therapeutic efficacy observed in experimental rodent uveitis to equine patient disease. Through bioinformatics and peptide binding assays we demonstrate putative binding of the SOCS1-KIR peptide to equine Jak2. We also show that topical, or intravitreal injection of SOCS1-KIR was well tolerated within the equine eye through physical and ophthalmic examinations. Finally, we show that topical SOCS1-KIR administration was associated with significant clinical ERU improvement. Together, these results provide a scientific rationale, and supporting experimental evidence for the therapeutic use of a SOCS1 mimetic peptide in RU.

Vitamin C functions as double-edge sword on cancer progression depending on ERK activation or inhibition mediated by its receptor SVCT2

The effect of Vitamin C (Vc) in oncotherapy was controversial for decades. And hyperactivation of extracellular signal-regulated kinase (ERK) drove tumorigenesis. Herein, we demonstrated that Vc activated ERK through sodium-dependent Vc transporter 2 (SVCT2), while high-dose Vc resulted in persistent ERK feedback inhibition following activation. Extracellular Vc binding to SVCT2 initiated ERK activation, then transmembrane transport of Vc induced dimerization of SVCT2. Activated ERK phosphorylated protein tyrosine phosphatase non-receptor type 12 (PTPN12) at Ser434 and inhibited PTPN12 activity, thus enhancing phosphorylation of Janus kinase 2 (JAK2), which phosphorylated growth factor receptor bound protein 2 (GRB2) at Tyr160 to promote GRB2 dimers dissociation and recruitment of GRB2 to SVCT2, leading to further ERK activation. Different cancers have different sensitivities to Vc, the dose effects of Vc on cancer phenotypes depended on that ERK was activated or inhibited. These findings suggest SVCT2 is a Vc receptor mediating the ERK-PTPN12-JAK2-GRB2-ERK positive feedback loop and a potential target for oncotherapy.

Extracellular HSP90α Induces MyD88−IRAK Complex-Associated IKKα/β−NF-κB/IRF3 and JAK2/TYK2−STAT-3 Signaling in Macrophages for Tumor-Promoting M2-Polarization

M2-polarization and the tumoricidal to tumor-promoting transition are commonly observed with tumor-infiltrating macrophages after interplay with cancer cells or/and other stroma cells. Our previous study indicated that macrophage M2-polarization can be induced by extracellular HSP90α (eHSP90α) secreted from endothelial-to-mesenchymal transition-derived cancer-associated fibroblasts. To extend the finding, we herein validated that eHSP90α-induced M2-polarized macrophages exhibited a tumor-promoting activity and the promoted tumor tissues had significant increases in microvascular density but decreases in CD4+ T-cell level. We further investigated the signaling pathways occurring in eHSP90α-stimulated macrophages. When macrophages were exposed to eHSP90α, CD91 and toll-like receptor 4 (TLR4) functioned as the receptor/co-receptor for eHSP90α binding to recruit interleukin (IL)-1 receptor-associated kinases (IRAKs) and myeloid differentiation factor 88 (MyD88), and next elicited a canonical CD91/MyD88–IRAK1/4–IκB kinase α/β (IKKα/β)–nuclear factor-κB (NF-κB)/interferon regulatory factor 3 (IRF3) signaling pathway. Despite TLR4-MyD88 complex-associated activations of IKKα/β, NF-κB and IRF3 being well-known as involved in macrophage M1-activation, our results demonstrated that the CD91-TLR4-MyD88 complex-associated IRAK1/4−IKKα/β−NF-κB/IRF3 pathway was not only directly involved in M2-associated CD163, CD204, and IL-10 gene expressions but also required for downregulation of M1 inflammatory cytokines. Additionally, Janus kinase 2 (JAK2) and tyrosine kinase 2 (TYK2) were recruited onto MyD88 to induce the phosphorylation and activation of the transcription factor signal transducer and activator of transcription-3 (STAT-3). The JAK2/TYK2−STAT-3 signaling is known to associate with tumor promotion. In this study, the MyD88−JAK2/TYK2−STAT-3 pathway was demonstrated to contribute to eHSP90α-induced macrophage M2-polarization by regulating the expressions of M1- and M2-related genes, proangiogenic protein vascular endothelial growth factor, and phagocytosis-interfering factor Sec22b.