Rationale for the evaluation of nintedanib as a treatment for systemic sclerosis–associated interstitial lung disease

Interstitial lung disease is a common manifestation of systemic sclerosis. Systemic sclerosis–associated interstitial lung disease is characterized by progressive pulmonary fibrosis and a reduction in pulmonary function. Effective treatments for systemic sclerosis–associated interstitial lung disease are lacking. In addition to clinical similarities, systemic sclerosis–associated interstitial lung disease shows similarities to idiopathic pulmonary fibrosis in the pathophysiology of the underlying fibrotic processes. Idiopathic pulmonary fibrosis and systemic sclerosis–associated interstitial lung disease culminate in a self-sustaining pathway of pulmonary fibrosis in which fibroblasts are activated, myofibroblasts accumulate, and the excessive extracellular matrix is deposited. Nintedanib is a tyrosine kinase inhibitor that has been approved for the treatment of idiopathic pulmonary fibrosis. In patients with idiopathic pulmonary fibrosis, nintedanib slows disease progression by decreasing the rate of lung function decline. In this review, we summarize the antifibrotic, anti-inflammatory, and attenuated vascular remodeling effects of nintedanib demonstrated in in vitro studies and in animal models of aspects of systemic sclerosis. Nintedanib interferes at multiple critical steps in the pathobiology of systemic sclerosis–associated interstitial lung disease, providing a convincing rationale for its investigation as a potential therapy. Finally, we summarize the design of the randomized placebo-controlled SENSCIS ® trial that is evaluating the efficacy and safety of nintedanib in patients with systemic sclerosis–associated interstitial lung disease

Pomalidomide in Patients with Interstitial Lung Disease due to Systemic Sclerosis: A Phase II, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel-group Study

OBJECTIVE: To evaluate the safety and efficacy of pomalidomide (POM) on forced vital capacity (FVC), modified Rodnan skin score (mRSS), and gastrointestinal (GI) symptomatology over 52 weeks of treatment in patients with interstitial lung disease due to systemic sclerosis (SSc). METHODS: Twenty-three adult patients diagnosed with SSc were randomized 1:1 POM:placebo (PBO). RESULTS: Mean change at Week 52 from baseline in predicted FVC% -5.2 and -2.8; mRSS -2.7 and -3.7; and UCLA Scleroderma Clinical Trial Consortium Gastrointestinal Tract (SCTC GIT 2.0) score 0.1 and 0.0, with POM and PBO, respectively. Statistical significance was not achieved for any of these 3 primary endpoints at 52 weeks. CONCLUSION: Because of recruitment challenges, subject enrollment was discontinued early. In an interim analysis, the study did not meet its Week 52 primary endpoints. Therefore, a decision was made to terminate all study phases. POM was generally well tolerated, with an adverse event profile consistent with the known safety and tolerability profile of POM in other diseases. Study results were neither positive nor negative because too few subjects were enrolled to make meaningful conclusions. Clinical Trials number: NCT01559129

The histone demethylase Jumonji domain-containing protein 3 (JMJD3) regulates fibroblast activation in systemic sclerosis.

OBJECTIVES: Systemic sclerosis (SSc) fibroblasts remain activated even in the absence of exogenous stimuli. Epigenetic alterations are thought to play a role for this endogenous activation. Trimethylation of histone H3 on lysine 27 (H3K27me3) is regulated by Jumonji domain-containing protein 3 (JMJD3) and ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX) in a therapeutically targetable manner. The aim of this study was to explore H3K27me3 demethylases as potential targets for the treatment of fibrosis. METHODS: JMJD3 was inactivated by small interfering RNA-mediated knockdown and by pharmacological inhibition with GSKJ4. The effects of targeted inactivation of JMJD3 were analysed in cultured fibroblasts and in the murine models of bleomycin-induced and topoisomerase-I (topoI)-induced fibrosis. H3K27me3 at the FRA2 promoter was analysed by ChIP. RESULTS: The expression of JMJD3, but not of UTX, was increased in fibroblasts in SSc skin and in experimental fibrosis in a transforming growth factor beta (TGFβ)-dependent manner. Inactivation of JMJD3 reversed the activated fibroblast phenotype in SSc fibroblasts and prevented the activation of healthy dermal fibroblasts by TGFβ. Pharmacological inhibition of JMJD3 ameliorated bleomycin-induced and topoI-induced fibrosis in well-tolerated doses. JMJD3 regulated fibroblast activation in a FRA2-dependent manner: Inactivation of JMJD3 reduced the expression of FRA2 by inducing accumulation of H3K27me3 at the FRA2 promoter. Moreover, the antifibrotic effects of JMJD3 inhibition were reduced on knockdown of FRA2. CONCLUSION: We present first evidence for a deregulation of JMJD3 in SSc. JMJD3 modulates fibroblast activation by regulating the levels of H3K27me3 at the promoter of FRA2. Targeted inhibition of JMJD3 limits the aberrant activation of SSc fibroblasts and exerts antifibrotic effects in two murine models

GWAS for systemic sclerosis identifies multiple risk loci and highlights fibrotic and vasculopathy pathways.

Systemic sclerosis (SSc) is an autoimmune disease that shows one of the highest mortality rates among rheumatic diseases. We perform a large genome-wide association study (GWAS), and meta-analysis with previous GWASs, in 26,679 individuals and identify 27 independent genome-wide associated signals, including 13 new risk loci. The novel associations nearly double the number of genome-wide hits reported for SSc thus far. We define 95% credible sets of less than 5 likely causal variants in 12 loci. Additionally, we identify specific SSc subtype-associated signals. Functional analysis of high-priority variants shows the potential function of SSc signals, with the identification of 43 robust target genes through HiChIP. Our results point towards molecular pathways potentially involved in vasculopathy and fibrosis, two main hallmarks in SSc, and highlight the spectrum of critical cell types for the disease. This work supports a better understanding of the genetic basis of SSc and provides directions for future functional experiments

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

Phenotypes Determined by Cluster Analysis and Their Survival in the Prospective European Scleroderma Trials and Research Cohort of Patients With Systemic Sclerosis

Objective: Systemic sclerosis (SSc) is a heterogeneous connective tissue disease that is typically subdivided into limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc) depending on the extent of skin involvement. This subclassification may not capture the entire variability of clinical phenotypes. The European Scleroderma Trials and Research (EUSTAR) database includes data on a prospective cohort of SSc patients from 122 European referral centers. This study was undertaken to perform a cluster analysis of EUSTAR data to distinguish and characterize homogeneous phenotypes without any a priori assumptions, and to examine survival among the clusters obtained. / Methods: A total of 11,318 patients were registered in the EUSTAR database, and 6,927 were included in the study. Twenty‐four clinical and serologic variables were used for clustering. / Results: Clustering analyses provided a first delineation of 2 clusters showing moderate stability. In an exploratory attempt, we further characterized 6 homogeneous groups that differed with regard to their clinical features, autoantibody profile, and mortality. Some groups resembled usual dcSSc or lcSSc prototypes, but others exhibited unique features, such as a majority of lcSSc patients with a high rate of visceral damage and antitopoisomerase antibodies. Prognosis varied among groups and the presence of organ damage markedly impacted survival regardless of cutaneous involvement. / Conclusion: Our findings suggest that restricting subsets of SSc patients to only those based on cutaneous involvement may not capture the complete heterogeneity of the disease. Organ damage and antibody profile should be taken into consideration when individuating homogeneous groups of patients with a distinct prognosis

CLINICAL AND EXPERIMENTAL RHEUMATOLOGY

Objective: To obtain experiences and expert opinion on treatment of SSc patients with TNF-alpha antagonists. Methods: An investigation was carried out among the EUSTAR centres into their expertise on use of TNF-alpha antagonists. Assessment forms on the frequency of TNF-alpha inhibitor use were distributed to EULAR Scleroderma Trials and Research Group (EUSTAR) centres. Afterwards, a three round Delphi exercise was performed to obtain expert consensus on the use of TNF-alpha inhibitors in SSc. Results: Seventy-nine centres returned information on use of TNF-alpha antagonists in SSc patients. A total of 65 patients were treated with TNF-alpha inhibitors in 14 different centres. Forty-eight of the 65 patients treated with TNF-alpha inhibitors improved. Improvement was mainly seen in patients with arthritis, whereas the effects on fibrosis varied. In the first round of the subsequent Delphi approach, 71 out of 79 experts stated that they would use TNF-alpha antagonists in SSc. Arthritis was suggested as an indication for TNF alpha antagonists by 75% of the experts. However; after the third stage of the Delphi exercise, the acceptance for the off-label use of TNF-alpha antagonists decreased and 59% recommended that TNF-alpha antagonists should not be used or only used in clinical trials in SSc patients, while 38% of the experts suggested the use of TNF-alpha antagonists for arthritis associated with SSc. Conclusions: Most of the experts do not recommend the routine use of TNF-alpha antagonists in systemic sclerosis. Arthritis might be a potential indication in SSc, although controlled clinical trials with TNF-alpha antagonists are needed before general recommendations can be given