microRNA-126 targeting PIK3R2 promotes rheumatoid arthritis synovial fibro-blasts proliferation and resistance to apoptosis by regulating PI3K/AKT pathway.

OBJECTIVE: The purpose of our study was to elucidate the impact of microRNA-126 (miR-126) targeting PIK3R2 gene on cell proliferation and apoptosis of rheumatoid arthritis synovial fibro-blasts (RASFs) by regulating PI3K/AKT signal pathway. METHODS: The synovial tissue samples of this study were from 55 RA patients undergoing joint replacement and 27 healthy people undergoing joint repair due to trauma. The target genes of miR-126 were collected by the TargetScan and PIK3R2 as the direct target gene of miR-126 was confirmed by dual-luciferase reporter assay system. Our experiment had five groups including the blank control, miR-126 mimic, miR-126 mimic control, miR-126 inhibitor and miR-126 inhibitor control groups. Additionally, real-time quantitative polymerase chain reaction (RT-qPCR), Western-Blot, cell counting kit (CCK-8) and flow cytometry were carried out in this study. RESULTS: Compared with healthy individuals, the RA patients had increased miR-126, but decreased PIK3R2 mRNA expressions in the synovial tissues. Pearson correlation analysis indicated that miR-126 expression was negatively correlated with PIK3R2 mRNA expression (all P<0.05). When compared with the blank group respectively, the miR-126 mimic group had raising cell proportions in S and G2/M phases with reduced rate of cell apoptosis, while the miR-126 inhibitor group had raising cell proportions in G0/G1 and G2/M phases with increased rate of cell apoptosis (all P<0.05). Besides, compared with the blank control group, the miR-126 mimic group had declined expression of PIK3R2 protein with ascended expression of PI3K and p-AKT (all P<0.05), while the miR-126 inhibitor group had increased expression of PIK3R2 protein with decreased expression of PI3K and p-AKT (all P<0.05). CONCLUSION: Our study demonstrated that down-regulation of miR-126 may indirectly inhibit PI3K/AKT signaling pathway to disrupt the imbalance between growth and death of RASFs by targeting PIK3R2, which may be clinically helpful to find therapeutic strategies directed toward miR-126 function for RA patients.

Epidemiology of Takayasu arteritis in Shanghai: A hospital-based study and systematic review.

BACKGROUND: Takayasu arteritis (TAK) is a rare large vessel vasculitis, and epidemiological data on TAK are lacking in China. Thus, we designed this study to estimate the TAK prevalence and incidence in residential Shanghai, China. METHODS: Data on diagnosed TAK cases aged over 16 years were retrieved from 22 tertiary hospitals in Shanghai through hospital electronic medical record systems between January 1, 2015 and December 31, 2017 to estimate the prevalence and incidence. A systematic literature review based on searches in PubMed, Ovid-Medline, Excerpta Medica Database (EMBASE), Web of Science, and China National Knowledge Infrastructure (CNKI) was performed to summarize TAK distribution across the world. RESULTS: In total 102 TAK patients, with 64% female, were identified. The point prevalence (2015-2017) was 7.01 (95% CI 5.65-8.37) cases per million, and the mean annual incidence was 2.33 (1.97-3.21) cases per million. The average age of TAK patients was 44 ± 16 years, with the highest prevalence (11.59 [9.23-19.50] cases per million) and incidence (3.55 [0.72 3.74] cases per million) in the 16 to 34 years population. Seventeen reports were included in the system review, showing that the epidemiology of TAK varied greatly across the world. The incidence and prevalence were both relatively higher in Asian countries, with the prevalence ranging 3.3-40 cases per million and annual incidence ranging 0.34-2.4 cases per million. CONCLUSIONS: The prevalence and incidence of TAK in Shanghai was at moderate to high levels among the previous reports. The disease burden varied globally among racial populations.

TNF-α -857 and -1031 polymorphisms predict good therapeutic response to TNF-α blockers in Chinese Han patients with ankylosing spondylitis.

AIM: To evaluate whether polymorphisms at -857, -1031, -308 and -238 positions of the TNF-α gene influence response to TNF-α-blocker therapy in Chinese Han patients with ankylosing spondylitis. PATIENTS & METHODS: A total of 106 patients with ankylosing spondylitis were recruited and genotyped for -857, -1031, -308 and -238 TNF-α gene polymorphisms. In total, 32 received infliximab and 74 received a recombinant human TNF-α receptor II-IgG Fc fusion protein (rhTNFR-Fc). At the end of 12 weeks, patients were assessed using the Assessment of SpondyloArthritis International Society (ASAS) 20, 40, 50 and 70 criteria. RESULTS: Polymorphisms at -308 and -238 did not affect therapeutic response. The -857 C/C genotype (p = 0.0021) responded better to therapy. The -1031 T/T genotype (p = 0.0004) showed better outcome. CONCLUSION: In Chinese Han ankylosing spondylitis patients, polymorphisms at the -308 and -238 positions of the TNF-α gene are unable to predict TNF-α-blocker response; however, -857 C/C and -1031 T/T genotypes have the ability to predict good response.