Spleen tyrosine kinase (Syk) is a key regulator of cell signaling induced by cytokines or Fc receptor engagement. However, the role of Syk in rheumatoid arthritis (RA) is not known yet. We investigated the pathways activated by Syk in tumor necrosis factor-␣ (TNF␣)-stimulated fibroblast-like synoviocytes (FLS) using the novel Syk inhibitor N4- (2,2-dimethyl-3-oxo-4H-pyrid

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We investigated risk factors for immune-related adverse events (irAEs) in patients treated with anti-programmed cell death protein1 antibody pembrolizumab. A retrospective medical record review was performed to identify all patients who received at least one dose of pembrolizumab at Samsung Medical Center, Seoul, Korea between June 2015 and December 2017. Three hundred and ninety-one patients were included in the study. Data were collected on baseline characteristics, treatment details, and adverse events. Univariate and multivariate logistic regression models were used to identify risk factors for irAEs. Sixty-seven (17.1%) patients experienced clinically significant irAEs; most commonly dermatologic disorders, followed by pneumonitis, musculoskeletal disorders, and endocrine disorders. Fourteen patients (3.6%) experienced serious irAEs (grade ≥ 3). Most common serious irAEs were pneumonitis (2.3%). Four deaths were associated with irAEs, all of which were due to pneumonitis. In multivariate regression analysis, a higher body mass index (BMI) and multiple cycles of pembrolizumab were associated with higher risk of irAEs (BMI: odds ratio [OR] 1.08, 95% confidence interval [CI] 1.01–1.16; pembrolizumab cycle: OR 1.15, 95% CI 1.08–1.22). A derived neutrophil-lymphocyte ratio (dNLR) greater than 3 at baseline was correlated with low risk of irAEs (OR 0.37, 95% CI 0.17–0.81). Our study demonstrated that an elevated BMI and higher number of cycles of pembrolizumab were associated with an increased risk of irAEs in patients treated with pembrolizumab. Additionally, increased dNLR at baseline was negatively correlated with the risk of developing irAEs.

The aim of this study was to compare the efficacy of immunosuppressive therapy alone with that of combination therapy involving immunosuppressants and anticoagulation for the treatment of venous thrombosis in Behcet's disease (BD). A retrospective analysis was made of 37 patients with venous thrombosis in BD. BD patients with venous thrombosis were divided into three groups: one group (N = 16) received immunosuppressive therapy alone, another group (N = 17) received immunosuppressant and anticoagulation combination therapy, and the third group (N = 4) received anticoagulation therapy only. Clinical and laboratory parameters and the recurrence of venous thrombosis were assessed. Venous thrombosis in BD appeared to have a more diffuse pattern than idiopathic type and a predilection for lower limbs. The most commonly involved sites were the superficial and common femoral veins. Recurrence of venous thrombosis occurred in two cases in the immunosuppressant group (12.5%), one case in the combination therapy group (5.9%), and three cases in the anticoagulant group (75%). No significant difference was found between recurrence in the immunosuppressant and combination therapy groups. Acute phase reactants were elevated in all six patients at the time of venous thrombosis recurrence. Our study suggests that immunosuppressive therapy is essential and that anticoagulation therapy might not be required for the treatment of deep venous thrombosis associated with BD.

Hypoxia-induced MMP-3 expression is exclusively regulated by HIF-1alpha, and hypoxia-induced MMP-1 or IL-8 expression appears to have salvage pathways other than the HIF-1alpha pathway. Together, these data provide new insight regarding the mechanism by which hypoxia participates in joint inflammation and destruction in RA.

SummaryMacrophages play a crucial role in the perpetuation of inflammation and irreversible cartilage damage during the development of rheumatoid arthritis (RA). LIGHT (TNFSF14) and its receptor TR2 (TNFRSF14) are known to have pro-inflammatory activities in foam cells of atherosclerotic plaques. We tested a hypothesis that LIGHT and TR2 are involved in activation of monocyte/macrophages in RA synovium. Immunohistochemical analysis of RA synovial tissue samples revealed that both LIGHT and TR2 are expressed in CD68 positive macrophages. In contrast, synovial tissue samples from osteoarthritis (OA) patients failed to reveal the expression of LIGHT. Expression of TR2 in RA synovial macrophages was also detected using flow cytometry analysis. To identify the role of LIGHT in the functioning of macrophages in RA, we isolated macrophage enriched cells from RA synovial fluid and stimulated them with LIGHT. LIGHT induced expression of matrix metalloproteinase-9 and pro-inflammatory cytokines such as tumor necrosis factor (TNF)-a, interleukin (IL)-6, and IL-8. These data indicate that LIGHT and TR2 expressed in macrophages are involved in the pathogenesis of RA by inducing the expression pro-inflammatory cytokines and matrix degrading enzymes.

We sought to evaluate the frequency of cervical spine (C-spine) involvement, and associated risk factors for this disorder and its progression in Korean patients with rheumatoid arthritis (RA). From 1995 to 2008, we recruited patients with RA attending the rheumatology clinic of a single tertiary care hospital, and evaluated 1,120 of the patients who had neck pain for C-spine involvement. A diagnosis of C-spine involvement was made in 28.6% of patients evaluated, and within this group, anterior atlantoaxial subluxation (AAS) and subaxial subluxation were found in 89.7 and 15%, respectively. Of the 1,120 patients, 570 patients were followed for more than 3 years. Comparing the clinical characteristics of 193 patients with C-spine involvement and 377 patients without C-spine involvement, we found the associations with female gender, RA diagnosis at or before age 45, erosive changes in hand or foot radiographs, C-reactive protein levels and erythrocyte sedimentation rates at the time of first visit, and combination disease-modifying anti-rheumatic drug (DMARD) therapy. We found using logistic regression analysis that significant predictors of C-spine involvement included erosion in hand or foot radiographs (OR = 2.22, p = 0.001) and RA diagnosis at or before age 45 (OR = 2.26, p < 0.001). Among 137 patients followed for more than 3 years, for whom at least two consecutive X-rays were available, we observed radiographic progression in 60.4%. Patients with and without radiologic evidence for cervical progression did not differ significantly in clinical characteristics. In conclusion, Korean patients with RA frequently show radiographic evidence for progressive involvement of the cervical spine. Significant risk factors for C-spine involvement may be associated with erosive peripheral joint disease and RA diagnosis at an early age.

Objective. Although p53 is overexpressed in rheumatoid arthritis (RA) synovial tissue (ST), few synoviocytes undergo apoptosis. This could be partly due to low expression of proapoptotic genes. Deficient p53 upregulated modulator of apoptosis (PUMA), which is a major effector of p53-mediated cell death, could contribute to this phenomenon. To evaluate a method to induce apoptosis, the expression and function of PUMA was investigated in ST and cultured fibroblast-like synoviocytes (FLS).Methods. PUMA expression in ST was measured by immunohistochemistry, Western blot analysis, and quantitative polymerase chain reaction analysis. Ad-p53 and plasmids encoding hemagglutinin-tagged, fulllength PUMA expression vector (HA-PUMA), PUMA lacking the Bcl-2 homology 3 domain, or pCEP4 were used to transfect FLS. Apoptosis was quantified by trypan blue exclusion, DNA fragmentation, and caspase 3 activation.Results. PUMA protein was detected in RA ST, although most of the immunoreactive protein was localized to sublining cells rather than the intimal lining synoviocytes. Western blot analysis showed no difference between RA ST and osteoarthritis (OA) ST. PUMA messenger RNA was detected in RA and OA ST, although the amounts were markedly lower than in the spleen and FLS. To determine if PUMA was inducible, FLS were transduced with Ad-p53. Even though p53 protein was produced and p21 expression was increased, PUMA expression was not enhanced. Consistent with this observation, Ad-p53 did not induce apoptosis in FLS. However, HA-PUMA transfection into FLS resulted in rapid apoptosis with the activation of caspase 3.Conclusion. PUMA can induce apoptosis by FLS and represents a potential target in RA.