Objective. To reevaluate the efficacy and safety of adjunctive low-dose methotrexate (MTX) in giant cell arteritis (GCA).Methods. An individual patient data metaanalysis of 3 randomized placebo-controlled trials in patients with newly diagnosed GCA was performed. Treatment consisted of initial high-dose corticosteroids and randomly assigned oral MTX therapy (7.5-15 mg/ week) or placebo. Time-to-event outcomes were compared between groups using Cox proportional hazards models stratified by trial, and continuous outcomes were compared by calculating weighted mean differences.Results. The combined data set comprised 161 patients, of whom 84 received MTX and 77 received placebo. The mean duration of followup was 54.7 weeks (SD 39.2 weeks). Hazard ratios (HRs) for a first and second relapse of GCA were 0.65 (P ‫؍‬ 0.04) and 0.49 (P ‫؍‬ 0.02), respectively, in patients receiving MTX as compared with patients receiving placebo. Accordingly, a predicted 3.6 individuals (95% confidence interval [95% CI] 2.2-56.8) and 4.7 individuals (95% CI 3.3-21.9) need to be treated with MTX to prevent the occurrence of one first or one second relapse, respectively, up to 48 weeks. Use of MTX resulted in a reduction in the corticosteroid cumulative dose by 842 mg within 48 weeks (P < 0.001). Moreover, MTX treatment was associated with a higher probability of achieving sustained discontinuation of corticosteroids for >24 weeks (HR 2.84, P ‫؍‬ 0.001). Dropout rates and occurrence of adverse events did not differ between treatment groups.Conclusion. In GCA, adjunctive treatment with MTX lowers the risk of relapse and reduces exposure to corticosteroids. These findings indicate that MTX could be considered as a therapeutic option in addition to standard-of-care treatment with corticosteroids for patients with GCA.

In spite of the extensive potential of human mesenchymal stem cells (hMSCs) in cell therapy, little is known about the molecular mechanisms that regulate their therapeutic properties. We aimed to identify microRNAs (miRNAs) involved in controlling the transition between the resting and reparative phenotypes of hMSCs, hypothesizing that these miRNAs must be present in the undifferentiated cells and downregulated to allow initiation of distinct activation/differentiation programs. Differential miRNA expression analyses revealed that miR-335 is significantly downregulated upon hMSC differentiation. In addition, hMSCs derived from a variety of tissues express miR-335 at a higher level than human skin fibroblasts, and overexpression of miR-335 in hMSCs inhibited their proliferation and migration, as well as their osteogenic and adipogenic potential. Expression of miR-335 in hMSCs was upregulated by the canonical Wnt signaling pathway, a positive regulator of MSC self-renewal, and downregulated by interferon-c (IFN-c), a pro-inflammatory cytokine that has an important role in activating the immunomodulatory properties of hMSCs. Differential gene expression analyses, in combination with computational searches, defined a cluster of 62 putative target genes for miR-335 in hMSCs. Western blot and 3 0 UTR reporter assays confirmed RUNX2 as a direct target of miR-335 in hMSCs. These results strongly suggest that miR-335 downregulation is critical for the acquisition of reparative MSC phenotypes. Mesenchymal stem cells (MSCs) are multipotent mesodermderived somatic stem cell (SSC) precursors of non-hematopoietic connective tissues that are present in the stroma of virtually all mammalian organs, especially bone marrow and subcutaneous fat (reviewed in Bernardo et al. 1 ). Upon activation by tissue damage, MSCs contribute to tissue-repair processes through a multitude of activities, including cell proliferation, differentiation and migration, and the regulation of angiogenesis and immune responses. There is growing evidence, in both animal and clinical models, that administration of ex vivo-expanded human MSCs (hMSCs) has potential to ameliorate many degenerative disorders; however, the specific molecular mechanisms underlying this therapeutic potential remain mostly unknown.MicroRNAs (miRNAs) are an extensive family of small (18-24 nucleotide), single-stranded non-coding RNAs, which regulate gene expression in eukaryotic cells by controlling the translation (usually by repression), stability and localization of specific mRNA targets. Computational predictions of miRNA targets indicate that each miRNA regulates hundreds of mRNAs, and that approximately one third of all mammalian protein-coding genes are regulated by miRNAs. 2 Functional studies show that miRNAs participate in virtually each cellular process investigated, and that alterations in their expression levels might underlie human diseases, including cardiovascular disease and cancer. There are also data indicating that mammalian miRNAs can be imported into the nucleu...

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.