Targeting Interleukin-6 Signaling in Clinic

Emerging trends in COVID-19 treatment: learning from inflammatory conditions associated with cellular therapies

Coronavirus disease 2019 (SARS-CoV2) is an active global health threat for which treatments are desperately being sought. Even though most people infected experience mild to moderate respiratory symptoms and recover with supportive care, certain vulnerable hosts develop severe clinical deterioration. While several drugs are currently being investigated in clinical trials, there are currently no approved treatments or vaccines for COVID-19 and hence there is an unmet need to explore additional therapeutic options. At least three inflammatory disorders or syndromes associated with immune dysfunction have been described in the context of cellular therapy. Specifically, Cytokine Release Syndrome (CRS), Immune Reconstitution Inflammatory Syndrome (IRIS), and Secondary Hemophagocytic Lymphohistiocytosis (sHLH) all have clinical and laboratory characteristics in common with COVID19 and associated therapies that could be worth testing in the context of clinical trials. Here we discuss these diseases, their management, and potential applications of these treatment in the context of COVID-19. We also discuss current cellular therapies that are being evaluated for the treatment of COVID-19 and/or its associated symptoms.

Coronavirus Disease-2019 Treatment Strategies Targeting Interleukin-6 Signaling and Herbal Medicine

Coronavirus disease-2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is evolving across the world and new treatments are urgently needed as with vaccines to prevent the illness and stem the contagion. The virus affects not only the lungs but also other tissues, thus lending support to the idea that COVID-19 is a systemic disease. The current vaccine and treatment development strategies ought to consider such systems medicine perspectives rather than a narrower focus on the lung infection only. COVID-19 is associated with elevated levels of the inflammatory cytokines such as interleukin-6 (IL-6), IL-10, and interferon-gamma (IFN-γ). Elevated levels of cytokines and the cytokine storm have been linked to fatal disease. This suggests new therapeutic strategies through blocking the cytokine storm. IL-6 is one of the major cytokines associated with the cytokine storm. IL-6 is also known to display pleiotropic/diverse pathophysiological effects. We suggest the blockage of IL-6 signaling and its downstream mediators such as Janus kinases (JAKs), and signal transducer and activators of transcription (STATs) offer potential hope for the treatment of severe cases of COVID-19. Thus, repurposing of already approved IL-6-JAK-STAT signaling inhibitors as well as other anti-inflammatory drugs, including dexamethasone, is under development for severe COVID-19 cases. We conclude this expert review by highlighting the potential role of precision herbal medicines, for example, the Cannabis sativa, provided that omics technologies can be utilized to build a robust scientific evidence base on their clinical safety and efficacy. Precision herbal medicine buttressed by omics systems science would also help identify new molecular targets for drug discovery against COVID-19.

Interleukin-6 Gene Expression Changes after a 4-Week Intake of a Multispecies Probiotic in Major Depressive Disorder-Preliminary Results of the PROVIT Study

Major depressive disorder (MDD) is a prevalent disease, in which one third of sufferers do not respond to antidepressants. Probiotics have the potential to be well-tolerated and cost-efficient treatment options. However, the molecular pathways of their effects are not fully elucidated yet. Based on previous literature, we assume that probiotics can positively influence inflammatory mechanisms. We aimed at analyzing the effects of probiotics on gene expression of inflammation genes as part of the randomized, placebo-controlled, multispecies probiotics PROVIT study in Graz, Austria. Fasting blood of 61 inpatients with MDD was collected before and after four weeks of probiotic intake or placebo. We analyzed the effects on gene expression of tumor necrosis factor (TNF), nuclear factor kappa B subunit 1 (NFKB1) and interleukin-6 (IL-6). In IL-6 we found no significant main effects for group (F(1,44) = 1.33, p = ns) nor time (F(1,44) = 0.00, p = ns), but interaction was significant (F(1,44) = 5.67, p < 0.05). The intervention group showed decreasing IL-6 gene expression levels while the placebo group showed increasing gene expression levels of IL-6. Probiotics could be a useful additional treatment in MDD, due to their anti-inflammatory effects. Results of the current study are promising, but further studies are required to investigate the beneficial effects of probiotic interventions in depressed individuals.

IL-6 trans-signaling induces plasminogen activator inhibitor-1 from vascular endothelial cells in cytokine release syndrome

Cytokine release syndrome (CRS) is a life-threatening complication induced by systemic inflammatory responses to infections, including bacteria and chimeric antigen receptor T cell therapy. There are currently no immunotherapies with proven clinical efficacy and understanding of the molecular mechanisms of CRS pathogenesis is limited. Here, we found that patients diagnosed with CRS from sepsis, acute respiratory distress syndrome (ARDS), or burns showed common manifestations: strikingly elevated levels of the four proinflammatory cytokines interleukin (IL)-6, IL-8, monocyte chemotactic protein-1 (MCP-1), and IL-10 and the coagulation cascade activator plasminogen activator inhibitor-1 (PAI-1). Our in vitro data indicate that endothelial IL-6 trans-signaling formed an inflammation circuit for robust IL-6, IL-8, and MCP-1 production and promoted PAI-1 production; additionally, an IL-6 signaling blockade by the human monoclonal antibody tocilizumab blunted endothelial cell activation. Plasma from severe COVID-19 patients similarly exhibited increased IL-6, IL-10, and MCP-1 levels, but these levels were not as high as those in patients with CRS from other causes. In contrast, the PAI-1 levels in COVID-19 patients were as highly elevated as those in patients with bacterial sepsis or ARDS. Tocilizumab treatment decreased the PAI-1 levels and alleviated critical illness in severe COVID-19 patients. Our findings suggest that distinct levels of cytokine production are associated with CRS induced by bacterial infection and COVID-19, but both CRS types are accompanied by endotheliopathy through IL-6 trans-signaling. Thus, the present study highlights the crucial role of IL-6 signaling in endothelial dysfunction during bacterial infection and COVID-19.

Frontline Science: Characterization and regulation of osteoclast precursors following chronic Porphyromonas gingivalis infection

Bone destruction in inflammatory osteolytic diseases including periodontitis is related to excessive activity of osteoclasts (OC), which originate from precursor cells of the myeloid lineage, termed osteoclast precursors (OCP). In contrast to ample knowledge that we currently have on mature OC, little is known about OCP and their regulation during bacterial infection. Therefore, this study aimed to identify and characterize OCP following chronic infection with a periodontal bacteria Porphyromonas gingivalis (Pg). We used a microosmotic pump to continually release Pg subcutaneously in a murine model. Two weeks after Pg infection, the frequency of CD11b⁺c-fms⁺Ly6C^hi population is significantly elevated within the bone marrow, spleen, and peripheral blood. In vitro and in vivo studies identified these cells as the OCP-containing population and Pg infection significantly enhanced the osteoclastogenic activity of these cells. Furthermore, mRNA sequencing analysis indicated a unique gene and pathway profile in CD11b⁺c-fms⁺Ly6C^hi population following Pg infection, with changes in genes and pathways related to OC differentiation, cell proliferation and apoptosis, inflammatory response, phagocytosis, and immunity, as well as antigen processing and presentation. Moreover, using IL-6 knockout mice, we found that IL-6 is important for Pg-induced accumulation of CD11b⁺c-fms⁺Ly6C^hi population from the bone marrow and periphery. Our results provide new insight into the characterization and regulation of OCP following a chronic bacterial infection. This knowledge is relevant to the understanding of the pathogenesis of bacteria-induced bone loss, and to the identification of potential therapeutic targets of bone loss diseases.

Targeting JAK-STAT Signaling to Control Cytokine Release Syndrome in COVID-19

Recent advances in the pathophysiologic understanding of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has indicated that patients with severe coronavirus disease 2019 (COVID-19) might experience cytokine release syndrome (CRS), characterized by increased interleukin (IL)-6, IL-2, IL-7, IL-10, etc. Therefore, the treatment of cytokine storm has been proposed as a critical part of rescuing severe COVID-19. Several of the cytokines involved in COVID-19 employ a distinct intracellular signaling pathway mediated by Janus kinases (JAKs). JAK inhibition, therefore, presents an attractive therapeutic strategy for CRS, which is a common cause of adverse clinical outcomes in COVID-19. Below, we review the possibilities and challenges of targeting the pathway in COVID-19.

Tocilizumab: A Therapeutic Option for the Treatment of Cytokine Storm Syndrome in COVID-19

Presently, we need more therapeutic molecules for this COVID-19 outbreak. The severity and mortality of the disease is associated with a high level of release of cytokine in the patients which is known as CRS (cytokine release syndrome) or cytokine storm syndrome. IL-6 is a type of pro-inflammatory cytokine which release in the severe COVID-19 patients. This cytokine initiates CRS the JAK-STAT or MAPK/NF-κB-IL-6 pathway. Tocilizumab, a humanized monoclonal antibody, is designed to bind both mIL-6R (membrane bound receptor for IL-6) and sIL-6R (soluble receptor for IL-6) and inhibit the JAK-STAT or MAPK/NF-κB-IL-6 signaling pathway. It finally stops the cytokine storm syndrome. However, we need to understand that how tocilizumab is bound with mIL-6R or sIL-6R. Similarly, we also need to understand more about the real molecular mechanism of activity of tocilizumab.

Tocilizumab for severe COVID-19 pneumonia: Case series of 5 Australian patients

AIM

To describe the first Australian cases of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV2) disease (COVID-19) pneumonia treated with the interleukin-6 receptor antagonist tocilizumab.

METHODS

Retrospective, open-label, real-world, uncontrolled, single-arm case series conducted in 2 tertiary hospitals in NSW, Australia and 1 tertiary hospital in Victoria, Australia. Five adult male patients aged between 46 and 74 years with type 1 respiratory failure due to COVID-19 pneumonia requiring intensive care unit (ICU) admission and biochemical evidence of systemic hyperinflammation (C-reactive protein greater than 100 mg/L; ferritin greater than 700 μg/L) were administered variable-dose tocilizumab.

RESULTS

At between 13 and 26 days follow-up, all patients are alive and have been discharged from ICU. Two patients have been discharged home. Two patients avoided endotracheal intubation. Oxygen therapy has been ceased in three patients. Four adverse events potentially associated with tocilizumab therapy occurred in three patients: ventilator-associated pneumonia, bacteremia associated with central venous catheterization, myositis and hepatitis. All patients received broad-spectrum antibiotics, 4 received corticosteroids and 2 received both lopinavir/ritonavir and hydroxychloroquine. The time from first tocilizumab administration to improvement in ventilation, defined as a 25% reduction in fraction of inspired oxygen required to maintain peripheral oxygen saturation greater than 92%, ranged from 7 hours to 4.6 days.

CONCLUSIONS

Tocilizumab use was associated with favorable clinical outcome in our patients. We recommend tocilizumab be included in randomized controlled trials of treatment for patients with severe COVID-19 pneumonia, and be considered for compassionate use in such patients pending the results of these trials.

Nanomedicine therapies modulating Macrophage Dysfunction: a potential strategy to attenuate Cytokine Storms in severe infections

Cytokine storms, defined by the dysregulated and excessive production of multiple pro-inflammatory cytokines, are closely associated with the pathology and mortality of several infectious diseases, including coronavirus disease 2019 (COVID-19). Effective therapies are urgently needed to block the development of cytokine storms to improve patient outcomes, but approaches that target individual cytokines may have limited effect due to the number of cytokines involved in this process. Dysfunctional macrophages appear to play an essential role in cytokine storm development, and therapeutic interventions that target these cells may be a more feasible approach than targeting specific cytokines. Nanomedicine-based therapeutics that target macrophages have recently been shown to reduce cytokine production in animal models of diseases that are associated with excessive proinflammatory responses. In this mini-review, we summarize important studies and discuss how macrophage-targeted nanomedicines can be employed to attenuate cytokine storms and their associated pathological effects to improve outcomes in patients with severe infections or other conditions associated with excessive pro-inflammatory responses. We also discuss engineering approaches that can improve nanocarriers targeting efficiency to macrophages, and key issues should be considered before initiating such studies.

A Review on Currently Available Potential Therapeutic Options for COVID-19

A series of unexplained pneumonia cases currently were first reported in December 2019 in Wuhan, China. Official names have been announced for the virus responsible, previously known as "2019 novel coronavirus" and the diseases it causes are, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease (COVID-19), respectively. Despite great efforts worldwide to control SARS-CoV-2, the spread of the virus has reached a pandemic. Infection prevention and control of this virus is the primary concern of public health officials and professionals. Currently, several therapeutic options for COVID-19 are proposed and vaccine development has been initiated for prevention purposes. In this review, we will discuss the most recent evidence about the current potential treatment options including anti-inflammatory drugs, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, nucleoside analogs, protease inhibitors, monoclonal antibodies, and convalescent plasma therapy. Some other agents such as vitamin D and melatonin, which were recommended as potential adjuvant treatments for COVID-19 infection are also presented. Moreover, the potential use of convalescent plasma for treatment of COVID-19 infection was described. Furthermore, in the next part of the current review, various vaccination approaches against COVID-19 including whole virus vaccines, recombinant subunit vaccine, DNA vaccines, and mRNA vaccines are discussed.

Cytokines and costimulation in acute graft-versus-host disease

Allogeneic hematopoietic stem cell transplantation (alloSCT) is an important curative therapy for high-risk hematological malignancies, but the development of severe and/or steroid-refractory acute graft-versus-host disease (aGVHD) remains a significant limitation to optimal outcomes. New approaches to prevent and treat aGVHD remain an unmet need that can be best addressed by understanding the complex disease pathophysiology. It is now clear that chemoradiotherapy used prior to alloSCT induces the release of endogenous alarmins (eg, HMGB-1, ATP, IL-1α, IL-33) from recipient tissue. Exogenous pathogen-derived molecules (eg, lipopolysaccharide, nucleic acids) also translocate from the gastrointestinal tract lumen. Together, these danger signals activate antigen-presenting cells (APCs) to efficiently present alloantigen to donor T cells while releasing cytokines (eg, interleukin-12 [IL-12], IL-23, IL-6, IL-27, IL-10, transforming growth factor-β) that expand and differentiate both pathogenic and regulatory donor T cells. Concurrent costimulatory signals at the APC-T-cell interface (eg, CD80/CD86-CD28, CD40-CD40L, OX40L-OX40, CD155/CD112-DNAM-1) and subsequent coinhibitory signals (eg, CD80/CD86-CTLA4, PDL1/2-PD1, CD155/CD112-TIGIT) are critical to the acquisition of effector T-cell function and ensuing secretion of pathogenic cytokines (eg, IL-17, interferon-γ, tissue necrosis factor, granulocyte-macrophage colony-stimulating factor) and cytolytic degranulation pathway effectors (eg, perforin/granzyme). This review focuses on the combination of cytokine and costimulatory networks at the T-cell surface that culminates in effector function and subsequent aGVHD in target tissue. Together, these pathways now represent robust and clinically tractable targets for preventing the initiation of deleterious immunity after alloSCT.

Safety and efficacy of tocilizumab versus azathioprine in highly relapsing neuromyelitis optica spectrum disorder (TANGO): an open-label, multicentre, randomised, phase 2 trial

BACKGROUND

Azathioprine is used as a first-line treatment to prevent relapses of neuromyelitis optica spectrum disorder (NMOSD). Tocilizumab has been reported to reduce NMOSD disease activity in retrospective case reports. We aimed to compare the safety and efficacy of tocilizumab and azathioprine in patients with highly relapsing NMOSD.

METHODS

We did an open-label, multicentre, randomised, phase 2 trial at six hospitals in China. We recruited adult patients (aged ≥18 years) with highly relapsing NMOSD diagnosed according to 2015 International Panel for Neuromyelitis Optica Diagnosis criteria, who had an Expanded Disability Status Scale (EDSS) score of 7·5 or lower, and had a history of at least two clinical relapses during the previous 12 months or three relapses during the previous 24 months with at least one relapse within the previous 12 months. Patients were randomly assigned (1:1) to intravenous tocilizumab (8 mg/kg every 4 weeks) or oral azathioprine (2-3 mg/kg per day) by an independent statistician using computer-generated randomisation software with permuted blocks of four. The central review committee, EDSS raters, laboratory personnel, and radiologists were masked to the treatment assignment, but investigators and patients were aware of treatment allocation. The minimum planned duration of treatment was 60 weeks following randomisation. The primary outcome was time to first relapse in the full analysis set, which included all randomly assigned patients who received at least one dose of study drug, and the per-protocol population, which included all patients who used azathioprine or tocilizumab as monotherapy. For the analyses of the primary outcome, the patients were prespecified into two subgroups according to concomitant autoimmune disease status. Safety was assessed in the full analysis set. This study is registered with ClinicalTrials.gov, NCT03350633.

FINDINGS

Between Nov 1, 2017, and Aug 3, 2018, we enrolled 118 patients, of whom 59 were randomly assigned to tocilizumab and 59 were randomly assigned to azathioprine. All 118 patients received one dose of study drug and were included in the full analysis set. 108 participants were included in the per-protocol analysis (56 in the tocilizumab group and 52 in the azathioprine group). In the full analysis set, median time to the first relapse was longer in the tocilizumab group than the azathioprine group (78·9 weeks [IQR 58·3-90·6] vs 56·7 [32·9-81·7] weeks; p=0·0026). Eight (14%) of 59 patients in the tocilizumab group and 28 (47%) of 59 patients in the azathioprine group had a relapse at the end of the study (hazard ratio [HR] 0·236 [95% CI 0·107-0·518]; p<0·0001). In the per-protocol analysis, 50 (89%) of 56 patients in the tocilizumab group were relapse-free compared with 29 (56%) of 52 patients in the azathioprine group at the end of the study (HR 0·188 [95% CI 0·076-0·463]; p<0·0001); the median time to first relapse was also longer in the tocilizumab group than the azathioprine group (67·2 weeks [IQR 47·9-77·9] vs 38·0 [23·6-64·9]; p<0·0001). In the prespecified subgroup analysis of the full analysis set stratified by concomitant autoimmune diseases, among patients without concomitant autoimmune diseases, three (9%) of 34 patients in the tocilizumab group and 13 (35%) of 37 patients in the azathioprine group had relapsed by the end of the study. Among patients with concomitant autoimmune diseases, a lower proportion of patients in the tocilizumab group had a relapse than in the azathioprine group (five [20%] of 25 patients vs 15 [68%] of 22 patients; HR 0·192 [95% CI 0·070-0·531]; p=0·0004). 57 (97%) of 59 patients in the tocilizumab group and 56 (95%) of 59 patients in the azathioprine group had adverse events. Treatment-associated adverse events occurred in 36 (61%) of 59 tocilizumab-treated patients and 49 (83%) of 59 azathioprine-treated patients. One death (2%) occurred in the tocilizumab group and one (2%) in the azathioprine group, but neither of the deaths were treatment-related.

INTERPRETATION

Tocilizumab significantly reduced the risk of a subsequent NMOSD relapse compared with azathioprine. Tocilizumab might therefore be another safe and effective treatment to prevent relapses in patients with NMOSD.

FUNDING

Tianjin Medical University, Advanced Innovation Center for Human Brain Protection, National Key Research and Development Program of China, National Science Foundation of China.

Structural Understanding of Interleukin 6 Family Cytokine Signaling and Targeted Therapies: Focus on Interleukin 11

Cytokines are small signaling proteins that have central roles in inflammation and cell survival. In the half-century since the discovery of the first cytokines, the interferons, over fifty cytokines have been identified. Amongst these is interleukin (IL)-6, the first and prototypical member of the IL-6 family of cytokines, nearly all of which utilize the common signaling receptor, gp130. In the last decade, there have been numerous advances in our understanding of the structural mechanisms of IL-6 family signaling, particularly for IL-6 itself. However, our understanding of the detailed structural mechanisms underlying signaling by most IL-6 family members remains limited. With the emergence of new roles for IL-6 family cytokines in disease and, in particular, roles of IL-11 in cardiovascular disease, lung disease, and cancer, there is an emerging need to develop therapeutics that can progress to clinical use. Here we outline our current knowledge of the structural mechanism of signaling by the IL-6 family of cytokines. We discuss how this knowledge allows us to understand the mechanism of action of currently available inhibitors targeting IL-6 family cytokine signaling, and most importantly how it allows for improved opportunities to pharmacologically disrupt cytokine signaling. We focus specifically on the need to develop and understand inhibitors that disrupt IL-11 signaling.

Nanoparticle-siRNA: A potential strategy for rheumatoid arthritis therapy?

Rheumatoid arthritis (RA) is a common clinical inflammatory disease of the autoimmune system manifested by persistent synovitis, cartilage damage and even deformities. Despite significant progress in the clinical treatment of RA, long-term administration of anti-rheumatic drugs can cause a series of problems, including infections, gastrointestinal reactions, and abnormal liver and kidney functions. The emergence of RNA interference (RNAi) drugs has brought new hope for the treatment of RA. Designing a reasonable vector for RNAi drugs will greatly expand the application prospects of RNAi. Nanoparticles as a promising drug carrier provide reliable support for RNAi drugs. The review summarizes the pathogenesis of RA as a possible target for small interference RNA (siRNA) design. At the same time, the review also analyzes the nanoparticles used in siRNA carriers in recent years, laying the foundation and prospect for the next step in the development of intelligent nanocarriers.

Correlation between cytokines and coagulation-related parameters in patients with coronavirus disease 2019 admitted to ICU

BACKGROUND

The novel SARS-CoV-2 caused a large number of infections and deaths worldwide. Thus, new ideas for an appropriated assessment of patients' condition and clinical treatment are of utmost importance. Therefore, in this study, the laboratory parameters of patients with coronavirus disease 2019 (COVID-19) were evaluated to identify the correlation between cytokine expression and other laboratory parameters.

METHODS

A retrospective and single-center study was performed in Wuhan, involving 83 severe or critical COVID-19 patients admitted to the intensive care unit (ICU). Laboratory parameters in ICU patients with laboratory-confirmed infection of SARS-CoV2 were collected. The association between parameters was assessed by Spearman's rank correlation.

RESULTS

Patients' median age was 66 years (IQR, 57-73), and 55 (66%) were men. Among the 83 patients, 61 (73%) had 1 or more coexisting medical condition. The median concentration of IL-2R, IL-6, IL8, IL10, and TNFα were above the normal range, without IL-1β. A significant negative correlation between IL-6 and platelet count was discovered (r² = -0.448, P < 0.001) as well as a significant correlation between IL-6 and other platelet parameters. Finally, a correlation between multiple cytokines and coagulation indicators was found, pro-inflammatory factors were found to be more associated to coagulation parameters, with the highest correlation between IL-6 and the International normalized ratio (INR) (r² = 0.444, P < 0.001).

CONCLUSIONS

Our results suggested that cytokines play an important role in the pathogenesis of COVID-19. In addition, IL-6 seems more relevant in the evaluation of the condition of COVID-19 patients.

Treatment of Severe COVID-19 with Tocilizumab Mitigates Cytokine Storm and Averts Mechanical Ventilation During Acute Respiratory Distress: A Case Report and Literature Review

COVID-19, caused by the novel severe acute respiratory coronavirus 2 (SARS-CoV-2), emerged in Wuhan, China, in 2019 and has resulted in the current pandemic. The disease continues to pose a major therapeutic challenge. Patient mortality is ultimately caused by acute respiratory distress syndrome (ARDS). Cytokine release syndrome (or "cytokine storm") is likely to be a contributing factor to ARDS in many patients. Because interleukin 6 (IL-6) is known to play a key role in inflammation, IL-6 receptor inhibitors such as tocilizumab may potentially treat COVID-19 by attenuating cytokine release. We present the case of a 48-year-old male with severe COVID-19, on the verge of meeting intubation requirements, who needed progressive oxygen support for respiratory distress. The patient was treated with a non-weight-based dosage of tocilizumab to prevent the onset of a cytokine storm. We chose to administer an IL-6 inhibitor because of the gradually increasing levels of acute phase reactants identified on serial blood draws, as well as his declining respiratory status. The treatment was well-tolerated in conjunction with standard drug therapies for COVID-19 (hydroxychloroquine, azithromycin, and zinc). The patient subsequently experienced marked improvements in his respiratory symptoms and overall clinical status over the following days. We believe that tocilizumab played a substantial role in his ability to avert clinical decline, particularly the need for mechanical ventilation. Ultimately, the patient was downgraded from the ICU and discharged within days. We highlight the potential of IL-6 inhibitors to prevent the progression of respiratory disease to a point requiring ventilator support. This case underscores the potential importance of early serial measurements of IL-6 and cytokine storm-associated acute phase reactants, such as ferritin, D-dimer, and C-reactive protein, in guiding clinical decision-making in the management of patients with suspected COVID-19. Conclusion: The early, proactive identification of serum acute phase reactants should be implemented in the treatment of COVID-19 in order to screen for a primary contributor to mortality-the cytokine storm. This screening, when followed by aggressive early treatment for cytokine storm, may have optimal therapeutic benefits and obviate the need for mechanical ventilation, thereby decreasing mortality. Additionally, we review current evidence regarding cytokine release syndrome in COVID-19 and the use of IL-6 receptor inhibition as a therapeutic strategy, and examine other reported cases in the literature describing IL-6 antagonist treatment for patients with COVID-19.

While We Wait for a Vaccine Against SARS-CoV-2, Why Not Think About Available Drugs?

At the time of reception of this article (April 2, 2020), efforts to develop a specific vaccine against SARS-Cov-2, the causative agent of the coronavirus disease 2019 (COVID-19), had just begun trial phase 1, but full validation of this and other current developments is likely to take many more months to reach completion. The ongoing pandemic constitutes a major health burden of world proportions that is also having a devastating impact on whole economies worldwide, the knock-on effects of which could be catastrophic especially in poorer countries. Alternative measures to ameliorate the impact and hamper or minimally slow down disease progression are urgently called for. This review discusses past and currently evolving data on the etiological agent of the current pandemic, SARS-CoV-2, and its host cell receptors with a view to disclosing alternative drugs for palliative or therapeutic approaches. Firstly, SARS-CoV-2 exhibits marked tropism for cells that harbor the membrane-bound metalloprotease angiotensin-converting enzyme 2 (ACE2) at their plasmalemma, predominantly in cells lining the oral cavity, upper respiratory tract, and bronchoalveolar cells, making these epithelial mucosae the most likely viral receptor cell targets and entry routes. Secondly, the crystal structures of several coronavirus spike proteins in complex with their cell host target receptors, and of SARS-Cov-2 in complex with an inhibitor, are now available at atomic resolution through X-ray diffraction and cryo-electron microscopy studies. Thirdly, viral entry of other viruses has been successfully blocked by inhibiting viral endogenous proteases or clathrin/dynamin-dependent endocytosis, the same internalization pathway followed by ACE2 and some viruses. Fourthly, the target cell-surface receptor molecules and SARS-CoV-2 possess other putative sites for drugs potentially modulating receptor activity or virus processing. A multi-pronged pharmacological approach attacking more than one flank of the viral-receptor interactions is worth considering as a front-line strategy.

Targeting GM-CSF in COVID-19 Pneumonia: Rationale and Strategies

COVID-19 is a clinical syndrome ranging from mild symptoms to severe pneumonia that often leads to respiratory failure, need for mechanical ventilation, and death. Most of the lung damage is driven by a surge in inflammatory cytokines [interleukin-6, interferon-γ, and granulocyte-monocyte stimulating factor (GM-CSF)]. Blunting this hyperinflammation with immunomodulation may lead to clinical improvement. GM-CSF is produced by many cells, including macrophages and T-cells. GM-CSF-derived signals are involved in differentiation of macrophages, including alveolar macrophages (AMs). In animal models of respiratory infections, the intranasal administration of GM-CSF increased the proliferation of AMs and improved outcomes. Increased levels of GM-CSF have been recently described in patients with COVID-19 compared to healthy controls. While GM-CSF might be beneficial in some circumstances as an appropriate response, in this case the inflammatory response is maladaptive by virtue of being later and disproportionate. The inhibition of GM-CSF signaling may be beneficial in improving the hyperinflammation-related lung damage in the most severe cases of COVID-19. This blockade can be achieved through antagonism of the GM-CSF receptor or the direct binding of circulating GM-CSF. Initial findings from patients with COVID-19 treated with a single intravenous dose of mavrilimumab, a monoclonal antibody binding GM-CSF receptor α, showed oxygenation improvement and shorter hospitalization. Prospective, randomized, placebo-controlled trials are ongoing. Anti-GM-CSF monoclonal antibodies, TJ003234 and gimsilumab, will be tested in clinical trials in patients with COVID-19, while lenzilumab received FDA approval for compassionate use. These trials will help inform whether blunting the inflammatory signaling provided by the GM-CSF axis in COVID-19 is beneficial.

Endocrine Conditions and COVID-19

COVID-19 was declared a global pandemic by the WHO and has affected millions of patients around the world. COVID-19 disproportionately affects persons with endocrine conditions, thus putting them at an increased risk for severe disease. We discuss the mechanisms that place persons with endocrine conditions at an additional risk for severe COVID-19 and review the evidence. We also suggest precautions and management of endocrine conditions in the setting of global curfews being imposed and offer practical tips for uninterrupted endocrine care.

Notch-Inflammation Networks in Regulation of Breast Cancer Progression

Members of the Notch family and chronic inflammation were each separately demonstrated to have prominent malignancy-supporting roles in breast cancer. Recent investigations indicate that bi-directional interactions that exist between these two pathways promote the malignancy phenotype of breast tumor cells and of their tumor microenvironment. In this review article, we demonstrate the importance of Notch-inflammation interplays in malignancy by describing three key networks that act in breast cancer and their impacts on functions that contribute to disease progression: (1) Cross-talks of the Notch pathway with myeloid cells that are important players in cancer-related inflammation, focusing mainly on macrophages; (2) Cross-talks of the Notch pathway with pro-inflammatory factors, exemplified mainly by Notch interactions with interleukin 6 and its downstream pathways (STAT3); (3) Cross-talks of the Notch pathway with typical inflammatory transcription factors, primarily NF-κB. These three networks enhance tumor-promoting functions in different breast tumor subtypes and act in reciprocal manners, whereby Notch family members activate inflammatory elements and vice versa. These characteristics illustrate the fundamental roles played by Notch-inflammation interactions in elevating breast cancer progression and propose that joint targeting of both pathways together may provide more effective and less toxic treatment approaches in this disease.

Immune disorder in endometrial cancer: Immunosuppressive microenvironment, mechanisms of immune evasion and immunotherapy

Immunotherapy is an emerging clinical approach that has gained traction over the past decade as a novel treatment option for lung cancer and melanoma. Notably, researchers have made marked improvements in the treatment of endometrial cancer (EC), and potential immune responses have been identified in patients with EC, thereby offering the possibility of exploring immunotherapy for EC. Nevertheless, various needs remain unmet, and immunotherapy applications in EC have yielded limited success, as only a minority of patients exhibited a clinical response. Therefore, further understanding of immune dysfunction associated with EC is still required. The present review describes recent findings regarding the immunosuppressive microenvironment of EC, with emphasis on immune evasion mechanisms and immunotherapy in EC.

IMMUNOPATHOLOGY AND IMMUNOPHARMACOTHERAPY OF CORONAVIRUS DISEASE 2019 (COVID-19): FOCUS ON INTERLEUKIN 6

The Coronavirus Disease 2019 (COVID-19) pandemic has drawn closer attention than ever before to the problems of the immunopathology of human diseases, many of which have been reflected when studying immune-mediated inflammatory rheumatic diseases (IIRDs). The hyperimmune response called a cytokine storm, the pathogenetic subtypes of which include hemophagocytic lymphohistiocytosis, macrophage activation syndrome, and cytokine release syndrome, is among the most serious complications of IIRDs or treatment for malignant neoplasms and may be a stage of COVID-19 progression. A premium is placed to interleukin-6 (IL-6) in the spectrum of cytokines involved in the pathogenesis of the cytokine storm syndrome. The clinical introduction of monoclonal antibodies (mAbs) that inhibit the activity of this cytokine (tocilizumab, sarilumab, etc.) is one of the major advances in the treatment of IIRDs and critical conditions within the cytokine storm syndrome in COVID-19. The review discusses data on the clinical and prognostic value of IL-6 and the effectiveness of anti-IL-6 receptor and anti-IL-6 mAbs, as well as prospects for personalized therapy of the cytokine storm syndrome in COVID-19.

Consideration of Severe Coronavirus Disease 2019 As Viral Sepsis and Potential Use of Immune Checkpoint Inhibitors

Taking into consideration the multisystemic clinical and autopsy findings in “severe” coronavirus disease 2019 patients, viral sepsis would be a more accurate term to describe the whole clinical picture. The most significant pathophysiological components of this picture are intense cytokine release, prolonged inflammation, immunosuppression with T cell exhaustion, and the development of organ dysfunctions. Currently, the optimal treatment for severe coronavirus disease 2019 is uncertain. Supportive treatment and immunomodulators have a critical place in the treatment of severe patients until effective antivirals are developed. Interleukin-6 antagonists, one of the immunomodulating agents, appears to be effective in the treatment of cytokine storm, but some patients continue to have severe lymphopenia and immunosuppression. We believe it can be useful as immunomodulator therapy in critical coronavirus disease 2019 patients because of the benefits of immune checkpoint inhibitors in cancer and sepsis patients.

IL-6-induced CD39 expression on tumor-infiltrating NK cells predicts poor prognosis in esophageal squamous cell carcinoma

Natural killer (NK) cells, a predominant innate lymphocyte subset, mediates eradicating malignant cells. Purinergic signaling by ectonucleotidase CD39 can suppress T-cell response in caner. However, the role of CD39 in NK cells has not been fully elucidated. Here, we characterized CD39 expression on NK cells and its clinical relevance in esophageal squamous cell carcinoma (ESCC). Peripheral blood and tissue samples were collected from 36 ESCC patients. We observed that the proportion of NK cells significantly decreased but CD39 was obviously up-regulated on NK cells from cancerous tissues compared to paired peripheral blood in ESCC patients. Furthermore, tumor-infiltrating NK cells with high CD39 expression exhibited a phenotype of functional impairment. In vitro, conditioned media of ESCC cell lines could induce CD39 expression on peripheral NK cells from healthy donors. IL-6 was identified as the major cytokine produced by ESCC cell lines and also elevated in both tumor tissues and blood serum from ESCC patients. Recombinant IL-6 significantly induced surface CD39 expression in human NK cells, while IL-6-receptor antagonist tocilizumab prevented this effect. Finally, tumor-infiltrating CD39⁺ NK cells were correlated with poor prognosis in ESCC patients. Thus, tumor-derived IL-6 might impair NK cell functions through induction of CD39 expression. CD39⁺ NK cells may serve as a potential prognostic biomarker for ESCC patients.

Engineering a potent receptor superagonist or antagonist from a novel IL-6 family cytokine ligand

Interleukin-6 (IL-6) family cytokines signal through multimeric receptor complexes, providing unique opportunities to create novel ligand-based therapeutics. The cardiotrophin-like cytokine factor 1 (CLCF1) ligand has been shown to play a role in cancer, osteoporosis, and atherosclerosis. Once bound to ciliary neurotrophic factor receptor (CNTFR), CLCF1 mediates interactions to coreceptors glycoprotein 130 (gp130) and leukemia inhibitory factor receptor (LIFR). By increasing CNTFR-mediated binding to these coreceptors we generated a receptor superagonist which surpassed the potency of natural CNTFR ligands in neuronal signaling. Through additional mutations, we generated a receptor antagonist with increased binding to CNTFR but lack of binding to the coreceptors that inhibited tumor progression in murine xenograft models of nonsmall cell lung cancer. These studies further validate the CLCF1-CNTFR signaling axis as a therapeutic target and highlight an approach of engineering cytokine activity through a small number of mutations.

Harnessing CAR T-cell Insights to Develop Treatments for Hyperinflammatory Responses in Patients with COVID-19

Cytokine release and macrophage activation contribute to immunopathology after SARS-CoV-2 infection. We discuss approaches to decrease the morbidity and mortality in patients with COVID-19 by repurposing existing drugs previously developed for cancer therapy.

The proinflammatory cytokines IL-1β and TNF-α modulate corneal epithelial wound healing through p16Ink4a suppressing STAT3 activity

The proinflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) are involved in the corneal inflammatory response and wound healing following corneal injuries. However, the mechanism by which proinflammatory cytokines modulate corneal epithelial wound healing remains unclear. In this study, we found that IL-1β or TNF-α was transiently elevated during corneal epithelial wound healing in mice. After corneal epithelial debridement, persistent treatment with IL-1β or TNF-α restrained the level of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) and boosted the level of cell cycle inhibitor p16^Ink4a , resulting in impaired corneal epithelial repair. When p16^Ink4a was deleted, the p-STAT3 level in corneal epithelium was enhanced and corneal epithelial wound healing was clearly accelerated. In diabetic mice, IL-1β, TNF-α, and p16^Ink4a appeared a sustained and strong expression in the corneal epithelium, and p16^Ink4a knockdown partially reverted the defective diabetic corneal epithelial repair. Furthermore, immunoprecipitation proved that p16^Ink4a interacted with p-STAT3 and thus possibly suppressed the STAT3 activity. Our findings revealed a novel mechanism that the proinflammatory cytokines modulate corneal epithelial wound healing via the p16^Ink4a -STAT3 signaling.

Antibiotics, Inflammation, and Preterm Labor: A Missed Conclusion

Regarding the risk of antibiotic therapy during pregnancy, any medication given to the mother should be according to the indications due to the risk of possible side effects. Antibiotics are one of the most important groups of these medications to be considered. Along with direct antibiotic-induced side effects, indirect pathways also affect the fetus through the maternal changes. According to the data, different cytokines including interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) are involved in both term and preterm parturition. These cytokines could trigger expression of different substances such as prostaglandins (PGs), their receptors, and PGs synthetizing molecules with already proven roles in parturition. Moreover, IL-1, IL-6, and TNF-α knocked-out mice have delayed parturition and lower levels of PGs compared to the wild types. The earlier-mentioned cytokines are able to induce matrix metalloproteinases and are also involved in parturition. Certain antibiotics have been shown capable of inducing inflammation cascade directly. Both in-vivo and in-vitro studies in human have also demonstrated this inflammation as elevated levels of inflammatory cytokines especially IL-1, IL-6, and TNF-α. This increase has been observed both in the presence and the absence of lipopolysaccharide (LPS). Moreover, antibiotics can induce endotoxemia in healthy cases which finally leads to the pro-inflammatory cytokine release. Regarding the role of mentioned pro-inflammatory cytokines in both term and preterm parturition, it seems that non-indicated use of antibiotics during pregnancy may increase the risk of preterm labor.

Tocilizumab, an anti-interleukin-6 receptor antibody, efficiently ameliorates persistent joint inflammation in rheumatoid arthritis

OBJECTIVES

To assess the efficacy of tocilizumab (TCZ) in the treatment of persistent arthritis in patients with rheumatoid arthritis (RA).

METHODS

The response to TCZ was evaluated in 304 patients with RA. TCZ treatment was completed after no fewer than 168 consecutive days between 28 May 2008 and 31 July 2019. Efficacy was evaluated using the DAS28-ESR and EULAR response criteria.

RESULTS

The mean DAS28-ESR decreased from 4.5 at baseline to 2.0 and 1.5, at 2 months and 1 year after treatment initiation, respectively, and was below 1.5 at 10 years. The retention rate within 1 year was 92.3%. TCZ re-administration to 74 patients with relapsed RA after TCZ withdrawal was also effective. The mean DAS28-ESR decreased from 4.4 at baseline to 1.8 and 1.6 at 2 months and 1 year after retreatment initiation, respectively. The mean swollen joint count decreased from 4.1 in initial TCZ administration and 2.8 in re-administration at baseline to 0.8 and 0.4 at 2 months, respectively. In all patients, good or moderate responses were achieved at least once within 12 months in both initial TCZ administration and re-administration.

CONCLUSION

TCZ efficiently ameliorated persistent arthritis in RA, regardless of initial administration and re-administration.

Six-month results of stenting of the femoropopliteal artery and predictive value of interleukin-6: Comparison with high-sensitivity C-reactive protein

OBJECTIVES

To determine the association of pre- and postinterventional serum levels of interleukin-6 and high-sensitivity C-reactive protein at the six-month evaluation of restenosis after stenting of the femoropopliteal artery.

METHODS

Sixty-eight consecutive patients with steno-occlusive femoropopliteal artery disease of Rutherford category III or IV who underwent stent implantation were included. Six-month patency was evaluated with color-coded duplex ultrasound. The association of in-stent restenosis with interleukin-6 and high-sensitivity C-reactive protein levels at baseline, and 24-h postintervention was assessed with a multivariate logistic regression analysis.

RESULTS

In-stent restenosis was found in 15 patients (22.1%) within six months. Interleukin-6 and high-sensitivity C-reactive protein levels were significantly increased at 24-h postintervention compared to their preintervention values (p < 0.001 and p = 0.002, respectively). Interleukin-6 values at baseline (odds ratio, 1.11; 95% confidence interval: 1.00, 1.23; p = 0.044) and 24-h postintervention (odds ratio, 1.04; 95% confidence interval: 1.02, 1.06; p < 0.001) were independently associated with six-month in-stent restenosis. Twenty-four-hour postinterventional high-sensitivity C-reactive protein levels were also found to be related to restenosis (odds ratio, 1.15; 95% confidence interval: 1.04, 1.26; p = 0.006), but high-sensitivity C-reactive protein levels at baseline did not show an independent association with in-stent restenosis (odds ratio, 0.57; 95% confidence interval: 0.35, 1.80; p = 0.667). Smoking, diabetes mellitus, and cumulative stent length were other parameters associated with an increased risk for in-stent restenosis.

CONCLUSIONS

Femoropopliteal artery angioplasty with stent placement induces an inflammatory response. Interleukin-6 is a powerful independent predictor of intermediate-term outcomes for stenting of the femoropopliteal artery, suggesting that its predictive value may be superior to that of high-sensitivity C-reactive protein.

Inhibitory Effects of Dietary N-Glycans From Bovine Lactoferrin on Toll-Like Receptor 8; Comparing Efficacy With Chloroquine

Toll-like receptor 8 (TLR-8) plays a role in the pathogenesis of autoimmune disorders and associated gastrointestinal symptoms that reduce quality of life of patients. Dietary interventions are becoming more accepted as mean to manage onset, progression, and treatment of a broad spectrum of inflammatory conditions. In this study, we assessed the impact of N-glycans derived from bovine lactoferrin (bLF) on the inhibition of TLR-8 activation. We investigated the effects of N-glycans in their native form, as well as in its partially demannosylated and partially desialylated form, on HEK293 cells expressing TLR-8, and in human monocyte-derived dendritic cells (MoDCs). We found that in HEK293 cells, N-glycans strongly inhibited the ssRNA40 induced TLR-8 activation but to a lesser extent the R848 induced TLR-8 activation. The impact was compared with a pharmaceutical agent, i.e., chloroquine (CQN), that is clinically applied to antagonize endosomal TLR- activation. Inhibitory effects of the N-glycans were not influenced by the partially demannosylated or partially desialylated N-glycans. As the difference in charge of the N-glycans did not influence the inhibition capacity of TLR-8, it is possible that the inhibition mediated by the N-glycans is a result of a direct interaction with the receptor rather than a result of pH changes in the endosome. The inhibition of TLR-8 in MoDCs resulted in a significant decrease of IL-6 when cells were treated with the unmodified (0.5-fold, p < 0.0001), partially demannosylated (0.3-fold, p < 0.0001) and partially desialylated (0.4-fold, p < 0.0001) N-glycans. Furthermore, the partially demannosylated and partially desialylated N-glycans showed stronger inhibition of IL-6 production compared with the native N-glycans. This provides evidence that glycan composition plays a role in the immunomodulatory activity of the isolated N-glycans from bLF on MoDCs. Compared to CQN, the N-glycans are specific inhibitors of TLR-8 activation and of IL-6 production in MoDCs. Our findings demonstrate that isolated N-glycans from bLF have attenuating effects on TLR-8 induced immune activation in HEK293 cells and human MoDCs. The inhibitory capacity of N-glycans isolated from bLF onTLR-8 activation may become a food-based strategy to manage autoimmune, infections or other inflammatory disorders.

Attenuation of the pro-inflammatory signature of lung cancer-derived mesenchymal stromal cells by statins

Solid tumor growth triggers a dynamic host response, which recapitulates wound healing and defines the tumor microenvironment (TME). In addition to the action of the tumor cells themselves, the TME is maintained by a myriad of immune and stromal cell-derived soluble mediators and extracellular matrix components whose combined action supports tumor progression. However, therapeutic targeting of the TME has proven challenging because of incomplete understanding of the tumor-host crosstalk at the molecular level. Here, we investigated the crosstalk between mesenchymal stromal cells (MSCs) and primary cancer cells (PCCs) from human squamous cell lung carcinoma (SCC). We discovered that PCCs secrete CCL3 and stimulate IL-6, CCL2, ICAM-1 and VCAM-1 expression in MSCs and that the MSC-PCC crosstalk can be disrupted by the lipid-lowering drug simvastatin, which displays pleiotropic effects on cell metabolism and suppresses IL-6 and CCL2 production by MSCs and CCL3 secretion by PCCs. In addition, simvastatin inhibited spheroid formation by PCCs and negatively affected PCC survival. Our observations demonstrate that commonly used statins may be repurposed to target the TME in lung carcinoma.

Targeting IL-6 receptor in the treatment of neuromyelitis optica spectrum: a review of emerging treatment options

Introduction: Recent research has shown that IL-6 receptor (IL-6 R) inhibitors like tocilizumab and satralizumab are effective in reducing the relapse rate in patients with NMOSD.Areas covered: This review article explores current concepts in NMOSD management and focuses on IL-6 R as a therapeutic target. The authors delve into the biological and immunological role of IL-6 in the pathogenesis of NMOSD. Further, the authors summarize the most recent findings on the use of anti-IL-6 R monoclonal antibodies, tocilizumab and satralizumab, in the treatment of NMOSD.Expert opinion: A better understanding of the role of cytokines in NMOSD may provide the neurologist with novel therapies for this disease. IL-6 R appears to be a central hub to NMOSD pathogenesis and a relevant therapeutic target.

Translating IL-6 biology into effective treatments

In 1973, IL-6 was identified as a soluble factor that is secreted by T cells and is important for antibody production by B cells. Since its discovery more than 40 years ago, the IL-6 pathway has emerged as a pivotal pathway involved in immune regulation in health and dysregulation in many diseases. Targeting of the IL-6 pathway has led to innovative therapeutic approaches for various rheumatic diseases, such as rheumatoid arthritis, juvenile idiopathic arthritis, adult-onset Still’s disease, giant cell arteritis and Takayasu arteritis, as well as other conditions such as Castleman disease and cytokine release syndrome. Targeting this pathway has also identified avenues for potential expansion into several other indications, such as uveitis, neuromyelitis optica and, most recently, COVID-19 pneumonia. To mark the tenth anniversary of anti-IL-6 receptor therapy worldwide, we discuss the history of research into IL-6 biology and the development of therapies that target IL-6 signalling, including the successes and challenges and with an emphasis on rheumatic diseases.

In this Perspective article, the authors recount the earliest stages of translational research into IL-6 biology and the subsequent development of therapeutic IL-6 pathway inhibitors for the treatment of autoimmune rheumatic diseases and potentially numerous other indications.

Role of M1-polarized tumor-associated macrophages in the prognosis of advanced ovarian cancer patients

The identification of prognostic and predictive markers is crucial for choosing the most appropriate management method for ovarian cancer patients. We aimed to assess the prognostic role of tumor-associated macrophage (TAM) polarization in advanced ovarian cancer patients. We carried out a prospective observational study that included 140 consecutive patients with advanced-stage high-grade serous ovarian cancer as well as patients with other histotypes of ovarian cancer and patients with ovarian metastasis from other sites between June 2013 and December 2018. Patients were enrolled at the time of laparoscopic surgery before receiving any antineoplastic treatment. We found that patients with high-grade serous papillary ovarian cancers had a prevalence of M1 TAMs, a higher M1/M2 ratio, and a longer overall survival (OS) and progression-free survival (PFS) than other patients. Regression analysis confirmed that there was a significant positive association between the M1/M2 ratio and an improved OS, PFS and platinum-free interval (PFI), both in the entire population and in patients stratified according to tumor type and initial surgery. Kaplan-Meier analysis was performed after the patients were divided into 2 groups according to the median M1/M2 ratio and revealed that patients with a high M1/M2 ratio had a higher OS, PFS and PFI than those with a low M1/M2 ratio. In conclusion, the prognostic and predictive role of TAM polarization in the tumor microenvironment could be of great clinical relevance and may allow the early identification of patients who are likely to respond to therapy. Further studies in a larger prospective sample are warranted.

Tumor-neuroglia interaction promotes pancreatic cancer metastasis

Rationale: The peripheral nervous system (PNS) plays an important role in tumor growth and progression. Schwann cells (SCs), the main glia cells of the PNS, augment cancer metastasis in contact-dependent or contact-independent manner in various malignancies. In the present study, we aimed to determine whether interplay between pancreatic cancer cells and SCs via paracrine signaling contributes to cancer progression.

Methods: Immunofluorescence analysis was performed to reveal the distribution of SCs in PDAC tissues and to determine the prognostic value and clinicopathological relevance of the level of intra‑tumoral SC markers for patients diagnosed with PDAC. Transwell assays and wound healing assays were carried out to investigate the influence of SC conditioned medium (SCM), SC co‑culture, or co-cultured CM on the migratory and invasive abilities of pancreatic cancer cells. The mechanism of SCs induced cancer cells migration and invasion was confirmed using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assays (ELISAs), western blotting, immunofluorescence, immunohistochemistry, siRNA-mediated gene interference, and an in vivo mouse model.

Results: Immunofluorescence analysis of tissue samples revealed that there were two different types of SCs distributed in the tumor microenvironment, the presence of which correlated with several clinicopathological characteristics and overall survival for patients with PDAC. Although SCM had no impact on the motility and invasiveness of tumor cells, both co-cultivation with SCs and co‑cultured CM enhanced pancreatic cancer cell migration and invasion. Mechanistically, SC‑derived Interleukin 6 (IL6), which was induced by co-culture with pancreatic cancer cells, augmented cancer cell migration and invasion by activating STAT3 signaling in cancer cells, while IL6 neutralization or STAT3 downregulation abrogated these effects. Furthermore, Interleukin 1β (IL1β), secreted by tumor cells, activated the nuclear actor (NF)-kappa B pathway in SCs, resulting in increased cytokines production, including IL6, while inhibiting the IL1β-IL1R1 axis led to inactivation of NF-kappa B signaling and downregulated cytokines expression in SCs. Interfering with tumor-neuroglia crosstalk impeded cancer cell dissemination in vivo.

Conclusion: Schwann cells were extensively distributed in the PDAC tumor microenvironment and high level of intra-tumoral SC markers could serve as an independent prognostic factor for poor survival of patients with PDAC. The tumor-neuroglia interaction is indispensable for SCs to acquire a tumor-facilitating phenotype. Targeting the tumor-neuroglia interplay might be a promising strategy to treat PDAC.

Therapeutic targets of thunder god vine (Tripterygium wilfordii hook) in rheumatoid arthritis (Review)

Celastrol and triptolide, chemical compounds isolated from Tripterygium wilfordii hook (also known as thunder god vine), are effective against rheumatoid arthritis (RA). Celastrol targets numerous signaling pathways involving NF‑κB, endoplasmic reticulum Ca2+‑ATPase, myeloid differentiation factor 2, toll‑like receptor 4, pro‑inflammatory chemokines, DNA damage, cell cycle arrest and apoptosis. Triptolide, inhibits NF‑κB, the receptor activator of NF‑κB (RANK)/RANK ligand/osteoprotegerin signaling pathway, cyclooxygenase‑2, matrix metalloproteases and cytokines. The present review examined the chemistry and bioavailability of celastrol and triptolide, and their molecular targets in treating RA. Clinical studies have demonstrated that T. wilfordii has several promising bioactivities, but its multi‑target toxicity has restricted its application. Thus, dosage control and structural modification of T. wilfordii are required to reduce the toxicity. In this review, future directions for research into these promising natural products are discussed.

Insights into the Immunopathophysiology of Severe COVID-19 in Metabolic Disorders

COVID-19 has affected millions of people across the world but disproportionately and severely affects persons with metabolic disorders such as obesity, diabetes mellitus and hypertension. In this brief review, we discuss the pathways of immune dysregulation that may lead to severe COVID-19 in persons with metabolic conditions.

[Biologicals and small molecules for rheumatoid arthritis]

In recent years tremendous progress has been made in the therapeutic management of rheumatoid arthritis. Rheumatologists now have a large armamentarium of highly efficient drugs with different mechanisms of action at their disposal. These new drugs consist of biologicals (biological disease-modifying antirheumatic drugs, bDMARDs) as well as targeted synthetic DMARDs (tsDMARD). A common feature of these new drugs for treatment of rheumatoid arthritis is that the molecular target of the drug is known, which is not the case for conventional DMARDs. With the help of the new drugs, the therapeutic goal of inducing remission in patients with rheumatoid arthritis has become reality for many patients. Nevertheless, there is still a significant proportion of patients who do not adequately respond to all available drugs, leaving room for still further improvement. This review gives a short overview on the currently available and effective substances for the treatment of rheumatoid arthritis.

High levels of proinflammatory cytokines IL-6 and IL-8 are associated with a poor clinical outcome in sickle cell anemia

Sickle cell anemia (SCA) pathophysiology is characterized by the activation of sickle red blood cells, reticulocytes, leukocytes, platelets, and endothelial cells, and with the expression of several inflammatory molecules. Therefore, it is conceivable that variations in levels of proinflammatory cytokines may act as a signaling of differential clinical course in SCA. Here, we evaluated the clinical impact of proinflammatory cytokines interleukin 1-β (IL-1β), interleukin 6 (IL-6), and interleukin 8 (IL-8) in 79 patients with SCA, followed in a single reference center from northeastern Brazil. The main clinical/laboratory data were obtained from patient interview and medical records. The proinflammatory markers IL-1β, IL-6, and IL-8 were evaluated by using commercially available enzyme-linked immunosorbent assay kits. According to levels of the proinflammatory markers, we observed that patients who had a higher frequency of VOC per year (P = 0.0236), acute chest syndrome (P = 0.01), leg ulcers (P = 0.0001), osteonecrosis (P = 0.0006), stroke (P = 0.0486), and priapism (P = 0.0347) had higher IL-6 levels compared with patients without these clinical complications. Furthermore, increased levels of IL-8 were found in patients who presented leg ulcers (P = 0.0184). No significant difference was found for IL-1β levels (P > 0.05). In summary, the present study emphasizes the role of inflammation in SCA pathophysiology, reveals an association of IL-8 levels and leg ulcer occurrence, and indicates that IL-6 levels can be used as a useful predictor for poor outcomes in SCA.

Expression of Interleukin-6 and the Interleukin-6 Receptor Predicts the Clinical Outcomes of Patients with Soft Tissue Sarcomas

Interleukin-6 (IL-6) affects the key parameters of oncogenesis, which increases the cell resistance to apoptosis, the proliferation of cancer cells, angiogenesis, invasion, malignancy, and the ability of tumor cells to respond to anticancer therapy. This study aimed to elucidate the association between IL-6 and IL-6 receptor (IL-6R) expression in tissues and clinical outcomes in patients with soft tissue sarcomas (STSs) because, to our knowledge, this has not been done before. We enrolled 86 patients with histologically-proven localized STSs who underwent surgical resection. The cohort included 48 men and 38 women, with a mean age of 65.6 years. The mean follow-up duration was 40.5 months. The expression of IL-6 and IL-6R was immunohistochemically determined. We analyzed prognostic factors for overall survival (OS) and metastasis-free survival (MFS). High IL-6 expression was observed in 23.3% (20/86), high IL-6R expression in 44.2% (38/86), and high expression of both in 16.3% (14/86) of patients. Multivariate analysis showed that a high expression of both IL-6 and IL-6R was a prognostic factor for OS and MFS. We found that this high expression indicated that the patient had a poor prognosis for OS and MFS.

Long Noncoding RNA RP11-334E6.12 Promotes the Proliferation, Migration and Invasion of Breast Cancer Cells Through the EMT Pathway by Activating the STAT3 Cascade

Background

RP11-334E6.12 is a dysregulated long noncoding RNA (lncRNA) that has never been studied in breast cancer. The biological function and potential mechanism of RNA RP11-334E6.12 in tumorigenesis are still unknown.

Methods

We scanned the Cancer Genome Atlas (TCGA) database and identified RP11-334E6.12 as one of the most dysregulated lncRNAs. The level of RP11-334E6.12 was assessed in breast cancer (BC) tissue samples and BC cell lines. The survival and RP11-334E6.12 expression of patients were analysed. The biological influence of RP11-334E6.12 on BC cell lines was studied using proliferation, Transwell migration, and invasion assays.

Results

RP11-334E6.12 was upregulated in both the TCGA database and our own database. Moreover, survival analyses indicated that RP11-334E6.12 was related to poor overall survival. Moreover, RP11-334E6.12 promoted the proliferation, migration and invasion of BC cells. RP11-334E6.12 promotes the epithelial mesenchymal transition of BC by activating the STAT3 pathway.

Conclusion

Taken together, our results demonstrate that RP11-334E6.12 is associated with the progression of breast cancer. Our findings indicate that long noncoding RNA RP11-334E6.12 promotes the proliferation, migration and invasion of breast cancer cells by activating the STAT3 pathway.

The evaluation of cytokines to help establish diagnosis and guide treatment of autoinflammatory and autoimmune diseases

Our knowledge of the role of cytokines in pathologic conditions has increased considerably with the emergence of molecular and genetic studies, particularly in the case of autoinflammatory monogenic diseases. Many rare disorders, considered orphan until recently, are directly related to abnormal gene regulation, and the treatment with biologic agents (biologics) targeting cytokine receptors, intracellular signaling or specific cytokines improve the symptoms of an increasing number of chronic inflammatory diseases. As it is currently impossible to systematically conduct genetic studies for all patients with autoinflammatory and autoimmune diseases, the evaluation of cytokines can be seen as a simple, less time consuming, and less expensive alternative. This approach could be especially useful when the diagnosis of syndromes of diseases of unknown etiology remains problematic. The evaluation of cytokines could also help avoid the current trial-and-error approach, which has the disadvantages of exposing patients to ineffective drugs with possible unnecessary side effects and permanent organ damages. In this review, we discuss the various possibilities, as well as the limitations of evaluating the cytokine profiles of patients suffering from autoinflammatory and autoimmune diseases, with methods such as direct detection of cytokines in the plasma/serum or following ex vivo stimulation of PBMCs leading to the production of their cytokine secretome. The patients' secretome, combined with biomarkers ranging from genetic and epigenetic analyses to immunologic biomarkers, may help not only the diagnosis but also guide the choice of biologics for more efficient and rapid treatments.

KSHV: Immune Modulation and Immunotherapy

Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) is associated with KS, primary effusion lymphoma (PEL), and multicentric Castleman disease (MCD). To ensure its own survival and propagation, KSHV employs an extensive network of viral proteins to subvert the host immune system, resulting in lifelong latent infection. Modulation of cellular and systemic immune defenses allows KSHV to persist in the host, which may eventually lead to the progression of KSHV-associated cancers. Due to KSHV's reliance on modifying immune responses to efficiently infect its host, immunotherapy is an attractive option for treating KSHV-associated malignancies. In this review, we will focus on the mechanisms by which KSHV evades the immune system and the current immune-related clinical strategies to treat KSHV-associated disease.

Activating the interleukin-6-Gp130-STAT3 pathway ameliorates ventricular electrical stability in myocardial infarction rats by modulating neurotransmitters in the paraventricular nucleus

Background

Malignant ventricular arrhythmia (VA) is the most common cause of death associated with acute myocardial infarction (MI). Recent studies have revealed direct involvement of the paraventricular nucleus (PVN) in the occurrence of VA. However, the underlying mechanisms remain incompletely understood. In this study, we investigated changes in the interleukin-6 (IL-6)-glycoprotein 130-signal transducer and activator of transcription 3 (STAT3) pathway in the PVN during acute MI and the effects of this pathway on ventricular stability.

Methods

Rats were divided into a control group, a MI group, a PVN-injected anti-IL-6 antibody group and a PVN-injected SC144 group to observe how IL-6 and its downstream glycoprotein 130-STAT3 pathway in the PVN affect ventricular stability. The left anterior descending coronary artery was ligated to induce MI. After that, an anti-IL-6 antibody and SC144 were injected into the PVNs of rats. All data are expressed as the mean ± SE and were analysed by ANOVA with a post hoc LSD test. p < 0.05 was considered to indicate statistical significance.

Results

After MI, the concentration of the inflammatory factor IL-6 increased, and its downstream glycoprotein 130-STAT3 pathway was activated in the PVN. After injection of MI rat PVNs with the anti-IL-6 antibody or glycoprotein 130 inhibitor (SC144), glutamate levels increased and γ-aminobutyric acid (GABA) levels decreased in the PVN. Plasma norepinephrine concentrations also increased after treatment, which increased the vulnerability to VA.

Conclusions

In summary, IL-6 in the PVN exerts a protective effect in MI rats, and the glycoprotein 130-STAT3 pathway plays a key role in this process. We anticipate that our findings will provide new ideas for the prevention and treatment of arrhythmia after MI.