The role of calcium and guanosine 3':5'-monophosphate in the action of acetylcholine on thyroid metabolism

Dissecting the regulatory network of transcription factors in T cell phenotype/functioning during GVHD and GVT

Transcription factors play a major role in regulation and orchestration of immune responses. The immunological context of the response can alter the regulatory networks required for proper functioning. While these networks have been well-studied in canonical immune contexts like infection, the transcription factor landscape during alloactivation remains unclear. This review addresses how transcription factors contribute to the functioning of mature alloactivated T cells. This review will also examine how these factors form a regulatory network to control alloresponses, with a focus specifically on those factors expressed by and controlling activity of T cells of the various subsets involved in graft-versus-host disease (GVHD) and graft-versus-tumor (GVT) responses.

Second-line therapy for patients with steroid-refractory aGVHD: systematic review and meta-analysis of randomized controlled trials

Objective

Steroids-refractory (SR) acute graft-versus-host disease (aGVHD) is a life-threatening condition in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT), but the optimal second-line therapy still has not been established. We aimed to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to compare the efficacy and safety of different second-line therapy regimens.

Methods

Literature search in MEDLINE, Embase, Cochrane Library and China Biology Medicine databases were performed to retrieve RCTs comparing the efficacy and safety of different therapy regimens for patients with SR aGVHD. Meta-analysis was conducted with Review Manager version 5.3. The primary outcome is the overall response rate (ORR) at day 28. Pooled relative risk (RR) and 95% confidence interval (CI) were calculated with the Mantel-Haenszel method.

Results

Eight eligible RCTs were included, involving 1127 patients with SR aGVHD and a broad range of second-line therapy regimens. Meta-analysis of 3 trials investigating the effects of adding mesenchymal stroma cells (MSCs) to other second-line therapy regimens suggested that the addition of MSCs is associated with significantly improvement in ORR at day 28 (RR = 1.15, 95% CI = 1.01-1.32, P = 0.04), especially in patients with severe (grade III-IV or grade C-D) aGVHD (RR = 1.26, 95% CI = 1.04-1.52, P = 0.02) and patients with multiorgan involved (RR = 1.27, 95% CI = 1.05-1.55, P = 0.01). No significant difference was observed betwwen the MSCs group and control group in consideration of overall survival and serious adverse events. Treatment outcomes of the other trials were comprehensively reviewed, ruxolitinib showed significantly higher ORR and complete response rate at day 28, higher durable overall response at day 56 and longer failure-free survival in comparison with other regimens; inolimomab shows similar 1-year therapy success rate but superior long-term overall survial in comparison with anti-thymocyte globulin, other comparisons did not show significant differences in efficacy.

Conclusions

Adding MSCs to other second-line therapy regimens is associated with significantly improved ORR, ruxolitinib showed significantly better efficacy outcomes in comparison with other regimens in patients with SR aGVHD. Further well-designed RCTs and integrated studies are required to determine the optimal treatment.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022342487.

Transcription Factors and Cancer: Approaches to Targeting

ABSTRACT

Cancer is defined by the presence of uncontrollable cell growth, whereby improper proliferative signaling has overcome regulation by cellular mechanisms. Transcription factors are uniquely situated at the helm of signaling, merging extracellular stimuli with intracellular responses. Therefore, this class of proteins plays a pivotal role in coordinating the correct gene expression levels for maintaining normal cellular functions. Dysregulation of transcription factor activity unsurprisingly drives tumorigenesis and oncogenic transformation. Although this imparts considerable therapeutic potential to targeting transcription factors, their lack of enzymatic activity renders intervention challenging and has contributed to a sense that transcription factors are "undruggable." Yet, enduring efforts to elucidate strategies for targeting transcription factors as well as a deeper understanding of their interactions with binding partners have led to advancements that are emerging to counter this narrative. Here, we highlight some of these approaches, focusing primarily on therapeutics that have advanced to the clinic.

Ruxolitinib-corticosteroid as first-line therapy for newly diagnosed high-risk acute graft versus host disease: study protocol for a multicenter, randomized, phase II controlled trial

BACKGROUND

The response rate of the first-line therapy with corticosteroid for acute graft versus host disease (aGVHD) is about 50%, and steroid-refractory disease is associated with high mortality. The improved response rate to the first-line therapy of newly diagnosed aGVHD patients would result in therapeutic benefits. Ruxolitinib, a selective Janus kinase (JAK) 1/2 inhibitor, has been approved for the treatment of steroid-refractory acute GVHD. The addition of ruxolitinib to the first-line therapy may improve the efficacy of corticosteroids.

METHODS

This investigator-initiated, open-label, multicenter, prospective randomized, and controlled two-arm phase II study compares the efficacy and safety of ruxolitinib combined with 1 mg/kg methylprednisolone versus 2 mg/kg methylprednisolone alone in newly diagnosed aGVHD patients. Patients with intermediate or high-risk aGVHD, as defined by the Minnesota aGVHD high-risk score and biomarker algorithm, are eligible for this study. A total of 198 patients will be randomized at a 1:1 ratio and assigned a GVHD risk (intermediate versus high risk) and disease status before transplantation (complete remission versus no complete remission). The primary endpoint is the overall response rate on day 28, which is defined as an improvement of at least one stage in the severity of aGVHD in one organ without deterioration in any other organ or disappearance of any GVHD signs from all organs without requiring new systemic immunosuppressive treatment. The secondary objectives consist of response time, response duration, overall survival, disease-free survival, non-relapse mortality, failure-free survival, and changes in serum levels of proinflammatory cytokines and GVHD-related biomarkers.

DISCUSSION

This open-label, multicenter, two-arm randomized trial will evaluate whether the addition of ruxolitinib combined with corticosteroid is superior to corticosteroid alone in newly diagnosed high-risk aGVHD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04061876 (version number: 2019.5.18). Registered on July 16, 2019.

Effect of ruxolitinib on the oral mucosa of patients with steroid-refractory chronic Graft-versus-Host disease and oral involvement

BACKGROUND

Chronic Graft-versus-Host Disease (cGVHD) can impact quality of life, especially in patients with oral involvement. Half of the patients with cGVHD do not respond to first-line therapy with corticosteroids and calcineurin inhibitors. Ruxolitinib is effective in steroid-refractory (SR)-cGVHD cases, but the long-term effects of ruxolitinib on the oral mucosa are unknown.

OBJECTIVE(S)

This study aims to assess the effect of ruxolitinib on the oral mucosa of SR-cGVHD patients with oral involvement.

MATERIALS AND METHODS

An observational longitudinal patient study was conducted in 53 patients with SR-cGVHD and oral involvement who were treated with ruxolitinib. The baseline condition of the oral mucosa was compared to its condition at 4 and 12 weeks after starting ruxolitinib.

RESULTS

The overall response was 81% (43/53), with a complete response in 53% (28/53) and partial response in 28% (15/53) after 12 weeks (p < 0.001). Men and patients concurrently using immunosuppressive therapy responded better than women (p = 0.005) and patients with ruxolitinib monotherapy (p = 0.02), respectively. At a longer follow-up (median 20 months), oral symptoms were comparable to the 12-week symptoms (p = 0.78), regardless of ruxolitinib use (p = 0.83).

CONCLUSION

Ruxolitinib treatment of SR-cGVHD patients with oral involvement was associated with a significant response of the oral manifestations at 12 weeks.

CLINICAL RELEVANCE

The oral mucosa of SR-cGVHD patients is likely to improve after 4 and 12 weeks of ruxolitinib treatment. Symptom severity at baseline does not affect the response of the oral mucosa.

IL-6 Responsiveness of CD4+ and CD8+ T Cells after Allogeneic Stem Cell Transplantation Differs between Patients and Is Associated with Previous Acute Graft versus Host Disease and Pretransplant Antithymocyte Globulin Therapy

Graft-versus-host disease (GVHD), one of the most common and serious complications after allogeneic stem cell transplantation, is mediated by allocative T cells. IL-6 mediates both pro- and anti-inflammatory effects and modulates T cell response through classical signaling and trans-signaling. We investigated the effects on the mTOR and JAK/STAT pathways after various types of IL-6 signaling for circulating T cells were derived from 31 allotransplant recipients 90 days post-transplant. Cells were stimulated with IL-6 alone, hyper-IL-6 (trans-signaling), IL-6+IL-6 receptor (IL-6R; classical + trans-signaling) and IL-6+IL-6R+soluble gp130-Fc (classical signaling), and flow cytometry was used to investigate the effects on phosphorylation of AKT (Thr308), mTOR (Ser2442), STAT3 (Ser727) and STAT3 (Tyr705). CD3⁺CD4⁺ and CD3⁺C8⁺ T cells responded to classical and trans IL-6 stimulation with increased STAT3 (Tyr705) phosphorylation; these responses were generally stronger for CD3⁺CD4⁺ cells. STAT3 (Tyr705) responses were stronger for patients with previous acute GVHD; CD3⁺CD4⁺ cells from GVHD patients showed an additional STAT3 (Ser727) response, whereas patients without acute GVHD showed additional mTOR (Ser2448) responses. Furthermore, treatment with antithymocyte globulin as a part of GVHD prophylaxis was associated with generally weaker STAT3 (Tyr705) responses and altered STAT3 (Ser727) responsiveness of CD3⁺CD4⁺ cells together with increased mTOR (Ser2448) responses for the CD3⁺CD8⁺ cells. Thus, early post-transplant CD3⁺CD4⁺ and CD3⁺ CD8⁺ T cell subsets differ in their IL-6 responsiveness; this responsiveness is modulated by antithymocyte globulin and differs between patients with and without previous acute GVHD. These observations suggest that allotransplant recipients will be heterogeneous with regard to the effects of post-transplant IL-6 targeting.

[Efficacy of basiliximab in the treatment of 87 cases of steroid-refractory or steroid-dependent acute graft-versus-host disease]

Objective: To evaluate the efficacy and prognosis of basiliximab in the treatment of steroid-refractory or steroid-dependent acute graft-versus-host disease (SR/SD-aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: Clinical data of 87 patients with SR/SD-aGVHD in the skin, intestine, and liver after allo-HSCT at the Institute of Hematology & Blood Diseases Hospital Transplantation Center from January 2015 to December 2018 were retrospectively analyzed. The administration plan of basiliximab was as follows: 20 mg for adults and children weighing ≥35 kg and 10 mg for children weighing<35 kg. The drug was administered once on the 1st, 4th, and 8th days, respectively, and then once weekly. The efficacy was evaluated on the 7th, 14th, 21st, and 28th days after basiliximab treatment. Results: ①There were 51 males (58.6%) and 36 females (41.4%) , with a median (range) age of 34 (4-63) years. There were 54 cases of classic aGVHD, 33 of late aGVHD, 49 of steroid-refractory aGVHD, and 38 of steroid-dependent aGVHD. ②Thirty-five patients (40.2%) achieved complete remission (CR) , 23 (26.4%) achieved partial remission (PR) , and 29 had no remission (NR) . The total effective rate[overall response rate (ORR) ] was 66.7% (58/87) . ③The ORR of the classic and late aGVHD groups was 77.8% (42/54) and 48.5% (16/33) , respectively. ④The median (range) follow-up time was 154 (4-1813) days, the 6-month overall survival (OS) rate of the 87 patients was 44.8% (95% CI 39.5%-50.1%) and the 1-year OS was 39.4% (95%CI 34.2%-44.3%) . ⑤After treatment with basiliximab, the 6-month OS in the CR (35 cases) , PR (23 cases) , and NR (29 cases) groups was 80.0% (95%CI 73.2%-86.8%) , 39.1% (95%CI 28.9%-49.3%) , and 6.9% (95%CI 2.2%-11.6%) , respectively (χ(2)=34.679, P<0.001) , and the 1-year OS was 74.3% (95%CI 66.9%-81.7%) , 30.4% (95%CI 20.8%-40.0%) , and 3.4% (95%CI 0%-6.8%) , respectively (χ(2)=43.339, P<0.001) . The OS of the classic and late aGVHD groups was 57.4% (95%CI 50.7%-64.1%) and 24.2% (95%CI 16.7%-31.7%) , respectively (χ(2)=9.109, P=0.004) , and the 1-year OS was 51.9% (95%CI 45.1%-58.7%) and 18.2% (95%CI 11.5%-24.9%) , respectively (χ(2)=9.753, P=0.003) . ⑥Univariate and multivariate analyses showed that late aGVHD (OR=3.121, 95%CI 1.770-5.503, P<0.001) , Minnesota score high-risk group before medication (OR=3.591, 95%CI 1.931-6.679, P<0.001) , active infection before medication (OR=1.881, 95%CI 1.029-3.438, P=0.040) , and impairment of important organ function caused by non-GVHD (OR=3.100, 95%CI 1.570-6.121, P=0.001) were independent risk factors affecting the efficacy of basiliximab. Conclusion: Basiliximab has good efficacy and safety for SR/SD-aGVHD, but not in patients with late aGVHD, high-risk group of Minnesota score, and infection or impaired function of important organs.

Treatment of Acute Graft-versus-Host Disease in Liver Transplant Recipients

Acute graft-versus-host disease (aGvHD) is a rare complication of liver transplantation associated with high morbidity and mortality. Death typically occurs due to complications related to severe infection, shock, and multiorgan failure. The clinical presentation involves dysfunction of multiple organ systems with overlapping symptoms that often results in a diagnostic delay. As there are a limited number of cases reported in the literature, there are no clear guidelines for treatment. Many different therapeutic measures have been utilized that target various immune system pathways, but steroids remain the first line of therapy. We report on two patients who developed aGvHD after liver transplantation who were treated with ruxolitinib, a novel Janus kinase 1/2 (JAK) inhibitor that has been shown to improve outcomes in steroid refractory cases of aGvHD after allogenic hematopoietic stem cell transplantation. We reviewed the literature to discuss various therapeutic options currently available for aGvHD after liver transplantation.

Immune Regulatory Processes of the Tumor Microenvironment under Malignant Conditions

The tumor microenvironment (TME) is a critical regulator of tumor growth, progression, and metastasis. Since immune cells represent a large fraction of the TME, they play a key role in mediating pro- and anti-tumor immune responses. Immune escape, which suppresses anti-tumor immunity, enables tumor cells to maintain their proliferation and growth. Numerous mechanisms, which have been intensively studied in recent years, are involved in this process and based on these findings, novel immunotherapies have been successfully developed. Here, we review the composition of the TME and the mechanisms by which immune evasive processes are regulated. In detail, we describe membrane-bound and soluble factors, their regulation, and their impact on immune cell activation in the TME. Furthermore, we give an overview of the tumor/antigen presentation and how it is influenced under malignant conditions. Finally, we summarize novel TME-targeting agents, which are already in clinical trials for different tumor entities.

Diagnosis and treatment of acute graft-versus-host disease after liver transplantation: Report of six cases

BACKGROUND

Graft-versus-host disease (GVHD) following liver transplantation (LT) is an unpredictable complication with poor outcome. However, consensus regarding the diagnosis and therapeutic regimen for the disease is yet lacking. The present study summarized the clinical experience on the diagnosis and treatment of acute GVHD (aGVHD) following LT and reviewed the pertinent literature.

CASE SUMMARY

Between January 1^st, 2000 and December 31^st, 2020, a total of 1053 LT were performed in the First Affiliated Hospital of Xi’an Jiaotong University. Six recipients developed aGVHD with clinical symptoms of fever, rash, diarrhea, and pancytopenia. The incidence of aGVHD was 0.57%. The median time from LT to the clinical presentation of aGVHD was 22.17 d. The median time from the beginning of the clinical symptom to histopathological diagnosis was 7.5 d. All six cases underwent treatment of immunosuppressant adjustment, corticosteroids, human normal immunoglobulin, and antithymocyte globulin/IL-2 antagonists. Despite intensive treatment strategies, 4 patients were deceased due to sepsis, multiple organ failure, and cerebral hemorrhage. The remaining two cases were discharged as treatment successfully. However, one died because of tuberculosis infection on the 6th month of follow-up, the other one was alive healthy during 30 mo of follow-up.

CONCLUSION

The rapid diagnosis of aGVHD is mainly based on the time from the first symptom, histopathological features, and the donor T-lymphocyte chimerism. Our cases report highlights massive corticosteroid therapy and age difference between donors and recipients could accelerate to aGVHD. Moreover, gut microbial interventions and donor-targeted serotherapy may provide novel therapeutics.

Efficiency and Toxicity of Ruxolitinib as a Salvage Treatment for Steroid-Refractory Chronic Graft-Versus-Host Disease

Graft-versus-host disease (GVHD), especially steroid-refractory GVHD, remains a life-threatening complication after hematopoietic stem cell transplantation (HSCT). The effect of the JAK1/2 kinase inhibitor ruxolitinib on treating steroid-refractory acute GVHD has been verified by the REACH1/2 study; however, its safety and efficacy in patients with steroid-refractory chronic GVHD (SR-cGVHD) remain unclear. In this retrospective study, 70 patients received ruxolitinib as a salvage therapy for SR-cGVHD. Twenty-four weeks after ruxolitinib treatment, the overall response rate (ORR) was 74.3% (52/70), including 34 patients who achieved complete remission (CR) and 18 who achieved partial remission (PR). The main adverse event was cytopenia, which occurred in 51.4% (36/70) of patients. After ruxolitinib treatment, the percentage of CD4 cells increased from 18.20% to 23.22% (P<0.001), while the percentages of NK (CD16⁺CD56⁺) cells and regulatory T cells (CD4⁺CD127 ^± CD25⁺) decreased (P<0.001, P<0.001). Among the B cell subsets, the proportion of total B cells approximately tripled from 3.69% to 11.16% (P<0.001). Moreover, we observed a significant increase in IL-10 levels after ruxolitinib treatment (P=0.025) and a remarkable decrease in levels of suppression of tumorigenicity 2 (ST2) from 229.90 ng/ml to 72.65 ng/ml. The median follow-up after the initiation of ruxolitinib treatment was 401 (6-1076) days. The estimated one-year overall survival rate of the whole group was 66.0% (54.4-77.6%, 95% CI), and the one-year overall survival rate of patients with mild and moderate cGVHD was 69.6% (57.4-81.8%, 95% CI), which was better than that of patients with severe cGVHD (31.3%, 0.0-66.2%, 95% CI) (P=0.002). Patients who achieved a CR and PR achieved better survival outcomes (84.5%, 73.9-95.1%, 95% CI) than those who showed NR to ruxolitinib treatments (16.7%, 0-34.3%, 95% CI) (P<0.001). At the final follow-up, cGVHD relapse occurred in six patients after they reduced or continued their ruxolitinib doses. Collectively, our results suggest that ruxolitinib is potentially a safe and effective treatment for SR-cGVHD.

Ruxolitinib mitigates steroid-refractory CRS during CAR T therapy

Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity are two major CAR T related toxicities. With the interventions of Tocilizumab and steroids, many patients can recover from severe CRS. However, some patients are refractory to steroids and develop life-threatening consequences. Ruxolitinib is an oral JAKs inhibitor and promising drug in inflammatory diseases. In this pilot study, we evaluate the efficacy of Ruxolitinib in CRS. Of 14 r/r B-ALL children who received CD19 or CD22 CAR T cell therapies, 4 patients developed severe (≥grade 3) CRS with symptoms that were not alleviated with high-dose steroids and thus received ruxolitinib. Rapid resolution of CRS symptoms was observed in 4 patients after ruxolitinib treatment. Serum cytokines significantly decreased after ruxolitinib intervention. All patients achieved complete remission on day 30 after infusion, and we could still detect CAR T expansion in vivo despite usage of ruxolitinib. There were no obvious adverse events related to ruxolitinib. In vitro assays revealed that ruxolitinib could dampen CAR T expansion and cytotoxicity, suggesting that the timing and dosage of ruxolitinib should be carefully considered to avoid dampening anti-leukaemia response. Our results suggest that ruxolitinib is active and well tolerated in steroid-refractory and even life-threatening CRS.

Cardiotoxicity of Novel Targeted Hematological Therapies

Chemotherapy-related cardiac dysfunction, also known as cardiotoxicity, is a group of drug-related adverse events negatively affecting myocardial structure and functions in patients who received chemotherapy for cancer treatment. Clinical manifestations can vary from life-threatening arrythmias to chronic conditions, such as heart failure or hypertension, which dramatically reduce quality of life of cancer survivors. Standard chemotherapy exerts its toxic effect mainly by inducing oxidative stress and genomic instability, while new targeted therapies work by interfering with signaling pathways important not only in cancer cells but also in myocytes. For example, Bruton’s tyrosine kinase (BTK) inhibitors interfere with class I phosphoinositide 3-kinase isoforms involved in cardiac hypertrophy, contractility, and regulation of various channel forming proteins; thus, off-target effects of BTK inhibitors are associated with increased frequency of arrhythmias, such as atrial fibrillation, compared to standard chemotherapy. In this review, we summarize current knowledge of cardiotoxic effects of targeted therapies used in hematology.

Factors Associated With 5- and 10-Year Survival After Intestinal Transplantation in Infants and Children

OBJECTIVES

Intestinal transplantation is an option for permanent intestinal failure with parenteral nutrition intolerance. We sought to determine long-term intestinal graft survival in pediatric patients at our center and to identify factors influencing survival.

METHODS

Retrospective chart review of 86 patients transplanted between 2003 and 2013, targeting potential explanatory variables related to demographics, perioperative factors, and postoperative complications.

RESULTS

Intestinal graft survival was 71% and 65% after 5 and 10 years, respectively. Five-year graft survival was attained in 79% of patients with a history of anatomic intestinal failure compared with 45% with functional intestinal failure (P = 0.0055). Compared with nonsurvival, 5-year graft survival was also associated with reduced incidences of graft-versus-host disease (2% vs 16%, P = 0.0237), post-transplant lymphoproliferative disorder (3% vs 24%, P = 0.0067), and de novo donor-specific antibodies (19% vs 57%, P = 0.0451) plus a lower donor-recipient weight ratio (median 0.727 vs 0.923, P = 0.0316). Factors not associated with 5-year intestinal graft survival included graft rejection of any severity and inclusion of a liver graft. Factors associated with graft survival at 10 years were similar to those at 5 years.

CONCLUSIONS

In our experience, outcomes in pediatric intestinal transplantation have improved substantially for anatomic but not functional intestinal failure. Graft survival depends on avoidance of severe infectious and immunological complications including GVHD, whereas inclusion of a liver graft provides no obvious survival benefit. Reduced success with functional intestinal failure may reflect inherently increased susceptibility to complications in this group.

The emerging role of Janus kinase inhibitors in the treatment of autoimmune and inflammatory diseases

Autoimmune and inflammatory diseases are common and diverse, and they can affect nearly any organ system. Much of the pathogenesis of these diseases is related to dysregulated cytokine activity. Historically, autoimmune and inflammatory diseases have been treated with medications that nonspecifically suppress the immune system. mAbs that block the action of pathogenic cytokines emerged 2 decades ago and have become widely useful. More recently, agents that simultaneously block multiple pathogenic cytokines via inhibition of the downstream Janus kinase (JAK)-signal transducer and activator of transcription pathway have emerged and are becoming increasingly important. These small-molecule inhibitors, collectively termed JAK inhibitors, are US Food and Drug Administration-approved in a few autoimmune/inflammatory disorders and are being evaluated in many others. Here, we review the biology of the JAK-signal transducer and activator of transcription pathway and the use of JAK inhibitors to treat autoimmune and inflammatory diseases across medical subspecialties.

Ruxolitinib Combined with Corticosteroids as First-Line Therapy for Acute Graft-versus-Host Disease in Haploidentical Peripheral Blood Stem Cell Transplantation Recipients

Corticosteroids are commonly used as first-line treatment for acute graft-versus-host disease (aGVHD); however, they are effective in only approximately one-half of patients. This study prospectively evaluated the use of ruxolitinib combined with 1 mg/kg methylprednisolone in the initial treatment of aGVHD. A total of 32 patients were enrolled. aGVHD involved the skin (53.1%), gastrointestinal tract (68.8%), and liver (6.0%). The complete response rate at day +28 was 96.9%. The 1-year and 2-year cumulative incidence rates of chronic GVHD were 9.4% and 13.8%, respectively. The 1- year cumulative incidence of nonrelapse mortality was 8.7%, and the Kaplan-Meier curve estimated 1-year overall survival after transplantation at 73.4%. This prospective study suggests that patients with aGVHD show a high response rate to ruxolitinib (5 mg/day) combined with 1 mg/kg/day methylprednisolone. This novel regimen was seen to spare steroid exposure, alleviate toxicity, and improve long-term survival.

Acute Graft-versus-Host Disease: Emerging Insights and Updates into Detection, Prevention, and Treatment

Acute graft-versus-host disease remains a devastating complication following hematopoietic cell transplantation, resulting in increased morbidity and mortality. Vast research efforts continue to refine or develop new means of prediction, assessment, prevention, and treatment of this syndrome. Recent updates in acute graft-versus-host disease include more definitive guidance and definitions for its grading and diagnosis. Biomarker use is being incorporated into early stages following hematopoietic cell transplantation to aid in the detection and prediction of long-term outcomes. New preventive strategies under investigation include the use of vedolizumab or tocilizumab as upfront prophylaxis. Finally, although steroids remain the backbone of therapy once treatment is warranted, the efficacy of several agents including vedolizumab, tocilizumab, ruxolitinib, and α1 antitrypsin are being evaluated as potential therapeutic options.

Inside Perspective of the Synthetic and Computational Toolbox of JAK Inhibitors: Recent Updates

The mechanisms of inflammation and cancer are intertwined by complex networks of signaling pathways. Dysregulations in the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway underlie several pathogenic conditions related to chronic inflammatory states, autoimmune diseases and cancer. Historically, the potential application of JAK inhibition has been thoroughly explored, thus triggering an escalation of favorable results in this field. So far, five JAK inhibitors have been approved by the Food and Drug Administration (FDA) for the treatment of different diseases. Considering the complexity of JAK-depending processes and their involvement in multiple disorders, JAK inhibitors are the perfect candidates for drug repurposing and for the assessment of multitarget strategies. Herein we reviewed the recent progress concerning JAK inhibition, including the innovations provided by the release of JAKs crystal structures and the improvement of synthetic strategies aimed to simplify of the industrial scale-up.

T cell-derived interferon-γ programs stem cell death in immune-mediated intestinal damage

Despite the importance of intestinal stem cells (ISCs) for epithelial maintenance, there is limited understanding of how immune-mediated damage affects ISCs and their niche. We found that stem cell compartment injury is a shared feature of both alloreactive and autoreactive intestinal immunopathology, reducing ISCs and impairing their recovery in T cell-mediated injury models. Although imaging revealed few T cells near the stem cell compartment in healthy mice, donor T cells infiltrating the intestinal mucosa after allogeneic bone marrow transplantation (BMT) primarily localized to the crypt region lamina propria. Further modeling with ex vivo epithelial cultures indicated ISC depletion and impaired human as well as murine organoid survival upon coculture with activated T cells, and screening of effector pathways identified interferon-γ (IFNγ) as a principal mediator of ISC compartment damage. IFNγ induced JAK1- and STAT1-dependent toxicity, initiating a proapoptotic gene expression program and stem cell death. BMT with IFNγ-deficient donor T cells, with recipients lacking the IFNγ receptor (IFNγR) specifically in the intestinal epithelium, and with pharmacologic inhibition of JAK signaling all resulted in protection of the stem cell compartment. In addition, epithelial cultures with Paneth cell-deficient organoids, IFNγR-deficient Paneth cells, IFNγR-deficient ISCs, and purified stem cell colonies all indicated direct targeting of the ISCs that was not dependent on injury to the Paneth cell niche. Dysregulated T cell activation and IFNγ production are thus potent mediators of ISC injury, and blockade of JAK/STAT signaling within target tissue stem cells can prevent this T cell-mediated pathology.

Impaired virus-specific T cell responses in patients with myeloproliferative neoplasms treated with ruxolitinib

Ruxolitinib is effective in myeloproliferative neoplasms (MPN) but can cause reactivation of silent infections. We aimed at evaluating viral load and T-cell responses to human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) in a cohort of 25 MPN patients treated with ruxolitinib. EBV-DNA and HCMV-DNA were quantified monthly using real-time polimerase chain reaction (PCR) on peripheral blood samples, and T-cell subsets were analyzed by flowcytometry. HCMV and EBV-directed T-cell responses were evaluated using the IFN-γ ELISPOT assay. Most patients had CD4+ and/or CD8+ T-cells below the normal range; these reductions were related to the duration of ruxolitinib treatment. In fact, reduced T-lymphocytes' subsets were found in 93% of patients treated for ≥5 years and in 45% of those treated for <5 years (P = .021). The former also had lower median numbers of CD4+ and CD8+ cells. Subclinical reactivation of EBV and HCMV occurred in 76% and 8% of patients. We observed a trend to an inverse relationship between EBV and CMV-specific CD4+ and CD8+ T-cell responses and viral load, and a trend to an inverse correlation with ruxolitinib dose. Therefore, our data suggest that the ruxolitinib treatment may interfere with immunosurveillance against EBV and HCMV.

Treatment and unmet needs in steroid-refractory acute graft-versus-host disease

Acute graft-versus-host disease (aGVHD) is a common complication of allogeneic hematopoietic stem cell transplantation (alloHCT) and is a major cause of morbidity and mortality. Systemic steroid therapy is the first-line treatment for aGVHD, although about half of patients will become refractory to treatment. As the number of patients undergoing alloHCT increases, developing safe and effective treatments for aGVHD will become increasingly important, especially for those whose disease becomes refractory to systemic steroid therapy. This paper reviews current treatment options for patients with steroid-refractory aGVHD and discusses data from recently published clinical studies to outline emerging therapeutic strategies.

Long-Term Use of Ruxolitinib in an AML Patient with Posttransplant Steroid Refractory GVHD

Ruxolitinib has become a new therapeutic option for steroid refractory graft-versus-host disease (srGVHD), with a substantial remission rate. Its anti-inflammatory properties by blocking interleukin pathways have made it a novel therapeutic approach to inflammatory disease processes, such as GVHD. The long-term use of ruxolitinib has not been explicitly studied outside the context in the treatment of multiple myeloma. With current clinical trials underway for the use of ruxolitinib in srGVHD, there are still no current guidelines or protocols for long-term clinical use. Of the available literature showing ruxolitinib utilization for srGVHD, most cases lead to resolution and eventual discontinuation. We present a case of a 32-year-old male on ruxolitinib with GVHD status postmatched unrelated donor stem cell transplant (MUD SCT) for acute myeloid leukemia (AML) with FLT3 mutation currently on ruxolitinib for 5 years who is not able to tolerate reduction in dosage due to flare-ups. We discuss the clinical implications and nuance of therapy with ruxolitinib with unknown long-term effects and weigh the risks and benefits.

Ruxolitinib add-on in corticosteroid-refractory graft-vs-host disease after allogeneic stem cell transplantation: Results from a retrospective study on 38 Chinese patients

BACKGROUND

Graft-vs-host disease (GVHD) is a major cause of mortality after allogeneic hematopoietic stem cell transplantation. Some patients have steroid-refractory (SR) GVHD.

AIM

To evaluate the effect and safety of ruxolitinib add-on in the treatment of patients with SR acute (a) and chronic (c) GVHD.

METHODS

We retrospectively analyzed 38 patients administered ruxolitinib add-on to standard immunosuppressive therapy for SR-aGVHD or SR-cGVHD following allogeneic hematopoietic stem cell transplantation. Ruxolitinib was administered 5-10 mg/d depending on disease severity, patient status, and the use of anti-fungal drugs. Overall response rate, time to best response, malignancy relapse rate, infection rate, and treatment-related adverse events were assessed.

RESULTS

The analysis included 10 patients with SR-aGVHD (grade III/IV, n = 9) and 28 patients with SR-cGVHD (moderate/severe, n = 24). For the SR-aGVHD and SR-cGVHD groups, respectively: Median number of previous GVHD therapies was 2 (range: 1-3) and 2 (1-4); median follow-up was 2.5 (1.5-4) and 5 (1.5-10) mo; median time to best response was 1 (0.5-2.5) and 3 (1-9.5) mo; and overall response rate was 100% (complete response: 80%) and 82.1% (complete response: 10.7%) with a response observed in all GVHD-affected organs. The malignancy relapse rates for the SR-aGVHD and SR-cGVHD groups were 10.0% and 10.7%, respectively. Reactivation rates for cytomegalovirus, Epstein-Barr virus, and varicella-zoster virus, respectively, were 30.0%, 10.0%, and 0% for the SR-aGVHD group and 0%, 14.3%, and 7.1% for the SR-cGVHD group.

CONCLUSION

Ruxolitinib add-on was effective and safe as salvage therapy for SR-GVHD.

Ruxolitinib for treatment of steroid-refractory graft-versus-host disease in adults: a systematic review and meta-analysis

Objectives: Authors assessed the impact of ruxolitinib (RUX) on steroid-refractory graft-versus-host disease (SR-GVHD) patients.Methods: Studies published before January 2019 were identified by electronic search of MEDLINE, EMBASE, Cochrane Library, Clinical Trials.Gov and Web of Science databases.Results: Sixteen cohort studies (414 adults) were included whose methodological quality ranged from poor to good. Pooled outcomes such as the response rates, steroid dose reduction, 1-year overall survival, overall infection, and grade 3 to 4 cytopenia were calculated separately for adults with steroid-refractory acute GVHD (aGVHD) and chronic GVHD (cGVHD). Further, the overall response rates were analyzed according to the affected organ. Adults with aGVHD as well as cGVHD showed high response with RUX, and steroid dose reduction was observed in both cases. Infection rates and cytopenia were important safety concerns for both aGVHD and cGVHD.Conclusion: Notwithstanding the need of randomized controlled trials to confirm the effect of RUX on SR-GVHD, response rates among adults with aGVHD and cGVHD seem to be high with the use of RUX as a salvage treatment, particularly in cases with gastrointestinal and cutaneous involvement. However, high rates of myelosuppression and infection remain a cause for concern regardless of aGVHD or cGVHD.

Janus Kinase Inhibition for Graft-Versus-Host Disease: Current Status and Future Prospects

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a curative treatment for many hematological malignant and non-malignant diseases. A major complication of the procedure is the donor T-cell-mediated graft-versus-host disease (GvHD). GvHD accounts for about 10% of early mortality after transplantation. GVHD is also the major cause of morbidity and disability in the late follow-up phase of transplanted patients, mainly because of the low response to first-line steroids, and the lack of efficient second-line standard treatments. The increasing knowledge regarding GVHD pathogenesis provides new pharmacological targets, potentially exploitable in clinical practice, in order to prevent and treat this complication. This review provides a description of GVHD pathogenesis, with a focus on the central role of the Janus kinase-related mechanisms. The first inflammatory innate-immunity response is triggered by a JAK/STAT dependent pathway, and JAK inhibition impairs antigen-presenting cell differentiation and activation and downregulates the expression of signals for T-cell triggering. The chronic evolution of alloreactivity, characterized by the long-term maintenance of inflammation and fibrosis, is also dependent on JAK/STAT activation. Based on preclinical data, we reviewed the rationale behind the clinical use of JAK-inhibitors in GVHD, presenting available results of clinical trials and reports, and looked at future implementation of this new promising treatment approach.

Targeting the JAK/STAT pathway in solid tumors

Aberrant activation of signal transducer and activator of transcription (STAT) proteins is associated with the development and progression of solid tumors. However, as transcription factors, these proteins are difficult to target directly. In this review, we summarize the role of targeting Janus kinases (JAKs), upstream activators of STATs, as a strategy for decreasing STAT activation in solid tumors. Preclinical studies in solid tumor cell line models show that JAK inhibitors decrease STAT activation, cell proliferation, and cell survival; in in vivo models, they also inhibit tumor growth. JAK inhibitors, particularly the JAK1/2 inhibitor ruxolitinib, sensitize cell lines and murine models to chemotherapy, immunotherapy, and oncolytic viral therapy. Ten JAK inhibitors have been or are actively being tested in clinical trials as monotherapy or in combination with other agents in patients with solid tumors; two of these inhibitors are already Food and Drug Administration (FDA) approved for the treatment of myeloproliferative disorders and rheumatoid arthritis, making them attractive agents for use in patients with solid tumors as they are known to be well-tolerated. Four JAK inhibitors (two of which are FDA approved for other indications) have exhibited promising anti-cancer effects in preclinical studies; however, clinical studies specifically assessing their activity against the JAK/STAT pathway in solid tumors have not yet been conducted. In summary, JAK inhibition is a viable option for targeting the JAK/STAT pathway in solid tumors and merits further testing in clinical trials.

Ruxolitinib treatment for SR-aGVHD in patients with EBV-HLH undergoing allo-HSCT

Ruxolitinib is a promising option for treating steroid-refractory acute graft-versus-host disease (SR-aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In this study, we describe ruxolitinib treatment for SR-aGVHD in HSCT patients with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) to evaluate its effectiveness. We evaluated the outcomes of 12 patients who received ruxolitinib for SR-aGVHD between January 2017 and March 2019. Of the 12 patients who received ruxolitinib, 7 patients achieved a complete response (CR), 3 had a partial response (PR), and 2 experienced treatment failure (TF). OS and CR rates were 83.3% and 58.3%, respectively. Moreover, CR was achieved by the six patients who had aGVHD with skin involvement. The mean time of steroid application in the patients who received ruxolitinib was 28.1 days. Median survival after HSCT was 64.6 weeks. The adverse effects of ruxolitinib included grades 3 to 4 neutropenia (n = 7) and grades 3 to 4 thrombocytopenia (n = 6). Cytomegalovirus reactivation was observed in three patients. A high rate of CR and short steroid application time of ruxolitinib as a salvage treatment were observed in HSCT patients with EBV-HLH. Consequently, from this study, it was determined that ruxolitinib is an optimal choice to treat SR-aGVHD in patients with EBV-HLH.

Emerging Topical and Systemic JAK Inhibitors in Dermatology

Accumulating data on cellular and molecular pathways help to develop novel therapeutic strategies in skin inflammation and autoimmunity. Examples are psoriasis and atopic dermatitis, two clinically and immunologically well-defined disorders. Here, the elucidation of key pathogenic factors such as IL-17A/IL-23 on the one hand and IL-4/IL-13 on the other hand profoundly changed our therapeutic practice. The knowledge on intracellular pathways and governing factors is shifting our attention to new druggable molecules. Multiple cytokine receptors signal through Janus kinases (JAKs) and associated signal transducer and activators of transcription (STATs). Inhibition of JAKs can simultaneously block the function of multiple cytokines. Therefore, JAK inhibitors (JAKi) are emerging as a new class of drugs, which in dermatology can either be used systemically as oral drugs or locally in topical formulations. Inhibition of JAKs has been shown to be effective in various skin disorders. The first oral JAKi have been recently approved for the treatment of rheumatoid arthritis and psoriatic arthritis. Currently, multiple inhibitors of the JAK/STAT pathway are being investigated for skin diseases like alopecia areata, atopic dermatitis, dermatomyositis, graft-versus-host-disease, hidradenitis suppurativa, lichen planus, lupus erythematosus, psoriasis, and vitiligo. Here, we aim to discuss the immunological basis and current stage of development of JAKi in dermatology.

Potent repression of C-reactive protein (CRP) expression by the JAK1/2 inhibitor ruxolitinib in inflammatory human hepatocytes

OBJECTIVE AND DESIGN

To determine whether inflammatory hepatocytes may constitute primary targets for ruxolitinib, a Janus kinase (JAK) inhibitor, its effects towards expression of hepatic acute-phase proteins, especially C-reactive protein (CRP), were assessed.

MATERIALS

Ruxolitinib effects were analysed in primary human hepatocytes and human hepatoma HepaRG cells exposed to various inflammatory stimuli.

RESULTS

Ruxolitinib was found to fully inhibit lipopolysaccharide (LPS)-induced CRP secretion and mRNA expression, at concentrations (IC₅₀ = 12.9 nM) achievable in human blood. It similarly repressed CRP up-regulation due to several Toll-like receptor agonists or pro-inflammatory cytokines [interleukin (IL) 1β, IL6 and tumour necrosis factor α] and counteracted LPS-mediated induction of serum amyloid A, fibrinogen, haptoglobin and serpin. Ruxolitinib was additionally found to block the activation of the IL6/JAK/signal transducer and activator of transcription (STAT) pathway triggered by LPS and whose inhibition by the neutralizing anti-IL6 receptor antibody tocilizumab prevented CRP induction.

CONCLUSION

Ruxolitinib can potently repress induction of CRP in inflammatory human hepatocytes, most likely through targeting the IL6/JAK/STAT signalling cascade. Hepatic production of acute-phase proteins during liver inflammation may, therefore, constitute a target for ruxolitinib.

IL-22 Accelerates Thymus Regeneration via Stat3/Mcl-1 and Decreases Chronic Graft-versus-Host Disease in Mice after Allotransplants

High-dose chemotherapy and/or radiation given before an allogeneic hematopoietic cell transplantation severely damage thymic epithelial cells (TECs), resulting in poor post-transplant immune recovery. IL-22 mediates recovery of TECs via a proregenerative effect, but the precise mechanism by which this occurs is unknown. In this study, we found IL-22 improved thymus recovery after damage from irradiation in association with increased number of TECs. This effect was blocked by ruxolitinib, a JAK1/JAK2 inhibitor. IL-22 increased the number of TECs via a Stat3-dependent signaling in the mTEC1 murine thymic epithelial cell line. This, in turn, upregulated transcription of myeloid cell leukemia sequence 1 (Mcl1), resulting in increased number of TECs. Similar effects were seen in irradiated mice given IL-22. Defects in IL-22 resulted in delayed thymus recovery in irradiated mice and had an impact on levels of thymus function-related genes such as Foxn1, Aire, and Kgf. In mice, post-transplant use of IL-22 improved repair of TECs, increased the numbers of thymus T cells, increased the intrathymic levels of Aire, and increased the proportion of natural regulatory T cells, resulting in decreased severity of chronic graft-versus-host disease (GVHD). Our data highlight the critical role of the IL-22/Stat3/Mcl-1 pathway in the regeneration of TECs after damage from irradiation in mice and highlight circumstances where normalizing thymus T cell function with IL-22 decreases GVHD after allotransplants.

JAK inhibitors for the treatment of autoimmune and inflammatory diseases

Cytokines play a central role in the pathophysiology of autoimmune and inflammatory diseases. Several cytokines signal through the JAK-STAT pathway, which is now recognized as a major target to inhibit the effect of a wide array of cytokines. JAK inhibitors are increasingly used in the setting of inflammatory and autoimmune diseases. While the currently approved drugs are panJAK inhibitors, more selective small molecules are being developed and tested in various rheumatic disorders. In this extensive review, we present evidence- or hypothesis-based perspectives for these drugs in various rheumatologic conditions, such as rheumatoid arthritis, systemic lupus erythematosus, giant cell arteritis, and autoinflammatory diseases.