14-3-3η Promotes Invadosome Formation via the FOXO3-Snail Axis in Rheumatoid Arthritis Fibroblast-like Synoviocytes

Serum 14‑3‑3η levels are increased and associated with a higher risk of osteoporosis in patients with rheumatoid arthritis: A meta‑analysis

14-3-3η can regulate the cell cycle, immunity, inflammation and the secretion of matrix metalloproteinases, while it may also be involved in the development of rheumatoid arthritis (RA) and promote bone injury. Therefore, the present meta-analysis focused on the dysregulated serum levels of 14-3-3η and its association with osteoporosis in patients with RA. Studies comparing the serum levels of 14-3-3η between patients with RA and healthy controls (HCs) or patients with RA with different bone mineral densities were retrieved from the EMBASE, Web of Science, PubMed and Cochrane databases. A total of 14 studies comprising 2,164 patients with RA and 1,136 HCs were included and analysed. Pooled analyses showed that the serum levels of 14-3-3η were enhanced in patients with RA compared with HCs [standardized mean difference (SMD): 1.34; 95% confidence interval (CI): 1.01-1.66; P<0.001]. In addition, the serum levels of 14-3-3η were also significantly higher in patients with RA with osteoporosis and osteopenia compared with those with normal bone mass (SMD: 1.96; 95% CI: 0.01-3.92; P=0.049 and SMD: 0.80; 95% CI: 0.09-1.52; P=0.028, respectively). Begg's and Egger's tests demonstrated that the publication bias for each evaluated indicator was low (all P>0.05). However, sensitivity analyses revealed that the findings were not very robust, which may be due to the omission of several individual studies. Overall, the present meta-analysis suggested that the serum levels of 14-3-3η were elevated and were associated with a higher risk of osteoporosis in patients with RA, thus supporting its potency as a circulating biomarker in the management of RA.

Scaffold Proteins in Autoimmune Disorders

Cells transmit information to the external environment and within themselves through signaling molecules that modulate cellular activities. Aberrant cell signaling disturbs cellular homeostasis causing a number of different diseases, including autoimmunity. Scaffold proteins, as the name suggests, serve as the anchor for binding and stabilizing signaling proteins at a particular locale, allowing both intra and intercellular signal amplification and effective signal transmission. Scaffold proteins play a critical role in the functioning of tight junctions present at the intersection of two cells. In addition, they also participate in cleavage formation during cytokinesis, and in the organization of neural synapses, and modulate receptor management outcomes. In autoimmune settings such as lupus, scaffold proteins can lower the cell activation threshold resulting in uncontrolled signaling and hyperactivity. Scaffold proteins, through their binding domains, mediate protein- protein interaction and play numerous roles in cellular communication and homeostasis. This review presents an overview of scaffold proteins, their influence on the different signaling pathways, and their role in the pathogenesis of autoimmune and auto inflammatory diseases. Since these proteins participate in many roles and interact with several other signaling pathways, it is necessary to gain a thorough understanding of these proteins and their nuances to facilitate effective target identification and therapeutic design for the treatment of autoimmune disorders.

The Pathogenesis of Rheumatoid Arthritis Breakthroughs in Molecular Mechanisms 1 and 2

The pathogenesis of rheumatoid arthritis (RA) consists of the formation of synovial villi, inflammation, immune abnormalities, and bone-cartilage destruction [...].

The rules and regulatory mechanisms of FOXO3 on inflammation, metabolism, cell death and aging in hosts

The FOX family of transcription factors was originally identified in 1989, comprising the FOXA to FOXS subfamilies. FOXO3, a well-known member of the FOXO subfamily, is widely expressed in various human organs and tissues, with higher expression levels in the ovary, skeletal muscle, heart, and spleen. The biological effects of FOXO3 are mostly determined by its phosphorylation, which occurs in the nucleus or cytoplasm. Phosphorylation of FOXO3 in the nucleus can promote its translocation into the cytoplasm and inhibit its transcriptional activity. In contrast, phosphorylation of FOXO3 in the cytoplasm leads to its translocation into the nucleus and exerts regulatory effects on biological processes, such as inflammation, aerobic glycolysis, autophagy, apoptosis, oxidative stress, cell cycle arrest and DNA damage repair. Additionally, FOXO3 isoform 2 acts as an important suppressor of osteoclast differentiation. FOXO3 can also interfere with the development of various diseases, including inhibiting the proliferation and invasion of tumor cells, blocking the production of inflammatory factors in autoimmune diseases, and inhibiting β-amyloid deposition in Alzheimer's disease. Furthermore, FOXO3 slows down the aging process and exerts anti-aging effects by delaying telomere attrition, promoting cell self-renewal, and maintaining genomic stability. This review suggests that changes in the levels and post-translational modifications of FOXO3 protein can maintain organismal homeostasis and improve age-related diseases, thus counteracting aging. Moreover, this may indicate that alterations in FOXO3 protein levels are also crucial for longevity, offering new perspectives for therapeutic strategies targeting FOXO3.

Serum 14-3-3η as predictor of clinical remission and progression of structural damage in early rheumatoid arthritis following a treat-to-target strategy in a randomized controlled trial

OBJECTIVE

14-3-3η is a proinflammatory mediator critical to joint destruction in rheumatoid arthritis (RA). We aimed to evaluate serum 14-3-3η for predicting disease activity and radiographic progression in patients with early RA in the double-blinded, randomized OPERA trial.

METHOD

180 patients with early RA were randomized to receive methotrexate (MTX) + adalimumab or MTX + placebo in combination with glucocorticoid injections into swollen joints. Disease activity was measured using the 28-joint Disease Activity Score-C-reactive protein (DAS28-CRP). Clinical remission was defined as DAS28-CRP < 2.6. X-rays of hands and feet were evaluated by the Total Sharp van der Heijde score (TSS). Radiographic progression was defined as exceeding the smallest detectable change (1.8 TSS-units). Serum 14-3-3η was determined by enzyme-linked immunosorbent assay. Multivariate logistic regression models were used to identify predictors of DAS28-CRP remission at 6 months and radiographic progression at 12 months.

RESULTS

Baseline 14-3-3η was a borderline significant independent predictor of radiographic progression at 12 months (odds radio = 1.02, 95% confidence interval 1.00-1.03, p = 0.05). In anti-cyclic citrullinated peptide antibody (ACPA)-negative patients, a moderate/high baseline 14-3-3η concentration increased the risk of radiographic progression at 12 months [4/51 (8%) vs 3/9 (33%), χ2 = 4.823, p = 0.028]. No value of 14-3-3η for predicting achievement of clinical remission was found.

CONCLUSION

Serum 14-3-3η was a borderline significant predictor of radiographic progression, particularly in ACPA-negative patients, but not of predicting achievement of clinical remission. Optimal cut-off levels of 14-3-3η for predicting radiographic progression in RA need further clarification.