ABSTRACT
Objective To investigate whether miR-17 plays a role in re-gulation of signal transducer and activator of transcription 3 (STAT3) expression,affecting the proliferation of rheumatoid arthritis synovial fibroblasts (RASFs) and the release of inflammatory factors from RASFs.Methods The synovial tissues of rheumatoid arthritis (RA) patients were collected.As a comparison,synovial tissues from osteoarthritis (OA) patients were collected as control,the expression of miR-17,STAT3 were detected.The results were analyzed by Mann-Whitney U test.To analyze the effects of interleukin (IL)-17A treatment on the expression of micro RNA-17 and STAT3,cell proliferation and secretion of IL-6 and IL-8 in RASFs cells.The effects of cell proliferation and secretion of IL-6 and IL-8 were analyzed by cell transfection of micro RNA-17 mimic and siRNA-STAT3.The results about RASFs cells were analyzed by t-testof two independent samples.Results Compared with OA patients,the expression of miR-17 in synovial tissues of RA patients decreased significantly (Mann-Whitney U=6,P＜0.01),while the expression of STAT3 increased obviously (Mann-Whitney U=32,P＜0.01).The expressions of IL-17A,IL-6 and IL-8 in synovial fluid of patients with OA were (53±12),(43±9) and (33±5),respectively,significantly lower than those of patients with RA [(170±30),(222±37) and (156±34),t=18.83,24.28,19.23,P＜0.01].IL-17A treatment significantly lowered the expression of miR-17 [(1.00 ±0.12) vs (0.37±0.04),t=8.63,P＜0.01],while up-regulated the expression of STAT3 [(1.00±0.14) vs (1.92 ±0.23),t =5.92,P＜0.01),promoted the proliferation of RASFs cells,and promoted the release of inflammatory factors IL-6 and IL-8.The results of the double luciferase reporter gene showed that there was a targeting regulation relationship between miR-17 and STAT3.Transfection of miR-17 mimic or siRNA-STAT3 could significantly reduce the expression of STAT3 and p-STAT3 in RASFs cells,along with the inhabitation of cell proliferation [miR-NC vs miR-17 mimic (26.9±2.8) vs (41.5±3.1),t=6.06,P＜0.01;siRNA-NC vs siRNA-STAT3 (23.5±2.4) vs (43.2±3.2),t=8.58,P＜0.01] and reduction of the secretion of inflammatory factors [miR-NC vs miR-17 mimic (110±13) vs (66±9),t=4.88,P＜0.01;siRNA-NC vs siRNA-STAT3 为(117±12) vs (70±6),t=6.10,P＜0.01] and IL-8 [miR-NC vs miR-17 mimic (127±10) vs (72±7),t=8.10,P＜0.01;siRNA-NC vs siRNA-STAT3 (123±11) vs (52±6),t=10.19,P＜0.01].Conclusion Decreased expression of miR-17 may play an important role in enhancing STAT3 expres-sion and promoting the pathogenesis of RA.Overexpression of miR-17 could inhibit STAT3 expression,atten-uate RASFs cell proliferation and inflammatory factor release.
ABSTRACT
Objective To examine the expression of miR-210,miR-155 and miR-34a in the peripheral blood of patients with systemic lupus erythematosus (SLE) and to analyze their clinical significance.Methods One hundred and teenty-six SLE patients were divided into the stable group (n=35),mild active group (n=49),medium and severe active group (n =42) based on systemic lupus erythematosus disease activity index (SLEDAI) score.Meanwhile,40 subjects for healthy check-up were selected as controls.The clinical data of patients were collected.Complete blood count,liver and kidney function and immunological indexes were tested in patients and the lupus activity index was assessed.The expression level of miR-210,miR-155 and miR-34a were determined by real-time polymerase chain reaction.Furthermore,the correlation between their levels and clinical parameters such as erythrocyte sedimentation rate (ESR),C-reactive protein (CRP),SLEDAI score,were analyzed.The expression levels of miR-210,miR-155 and miR-34a in each group were compared by one-way analysis of variance (ANOVA).Correlation analysis was performed by non parametric Spearman test.The difference was statistically significant if P＜0.05.The diagnostic value of SLE was evaluated by the subjects characteristic (ROC) curve.Results The levels of miR-210 and miR-155 were no significantly differencet between the stable group (0.017±0.012);(0.150±0.101) and the control group (0.015±0.010);(0.071±0.034),but they were increased in mild active group (0.502±0.166);(1.521±1.138),medium and severe active group(1.237±0.584),(13.589±9.827) (F=124.321,70.065,P＜0.05).The average expression level of miR-34a in the control group,the stable group,the mild active group and the moderate and severe active group were (0.005±0.003),(0.249±0.137),(2.981±1.762) and (9.625±5.873) respectively,and showed a trend of increase in turn (F=75.688,P＜0.05).The expression level of miR-210,miR-155 and miR-34a was not significantly different between the LN group and the non LN group (P＞0.05).The R values of miR-210,miR-155,miR-34a and each index were IgG (0.347;0.518;0.482);IgA (0.463;0.635;0.379);IgM (0.287;0.392;0.336),ESR(0.317;0.428;0.369),C3(0.243;0.429;0.381),C4(0.317;0.513;0.429),ANA titer (0.462;0.594;0.527),Anti-ds-DNA antibodies (0.391;0.586;0.483),SLEDAI scores (-0.412;-0.558;-0.493),and there were significant correlations (P＜0.05).In patients with SLE,there was no significant correlation between hormone therapy alone or hormone plus immunosuppressive therapy (P＞0.05).The sensitivity and specificity of miR-210,miR-155,miR-34a in combination for the diagnosis of SLE reached 75.7％ and 72.3％,respectively.Conclusion The levels of miR-210,miR-155 and miR-34a in combination may be used as bio-markers for the diagnosis of SLE.