Aberrant expression of miR-127 in rheumatoid arthritis and its related mechanism
Objective: This study aims to investigate the role and mechanism of miR-127 in rheumatoid arthritis (RA).
Methods: Totally 30 cases of RA patients were enrolled and 30 cases of healthy volunteers were enrolled as the control group. Peripheral blood samples and synovial tissues of the participators were collected, and RT-qPCR has been performed to detect the expression of miR-127; moreover, fibroblast-like synoviocytes (SFs) of patients with RA were cultured and stimulated with TNF-α, and transfected with miR-127 mimics, and MTT assay as well flow cytometry assay have been performed to examine the effect of miR-127 on the proliferation and apoptosis of SFs; furthermore, cells were collected, and RT-qPCR as well as western blot assays have been performed to examine the expression of Bcl-2, Bax and OPN; finally, dual luciferase assay was used to validate whether miR-127 directly target OPN.
Results: It was found that miR-127 was significantly decreased in blood and synovial tissues of RA patients, while OPN expression was significantly decreased in synovial tissues of patients with RA (P<0.05). Next, transfection of miR-127 mimics induced significant increase in the proliferation and marked decrease in the apoptosis of SFs isolated from patients with RA. Moreover, transfection of miR-127 mimics also induced significant decrease in the expression of OPN and Bax, and marked increase in the expression of Bcl-2. Finally, results of dual luciferase assay showed that miR-127 can directly target OPN.
Conclusion: OPN was significantly increased in RA patients, which might be associated with the down-regulation of miR-127. miR-127 may promote the development and progression of RA through targeting OPN.
Key word: miR-127, rheumatoid arthritis, Osteopontin