In conclusion, GAS5 and miR-21 in CD4<sup>+</sup> T cells may serve as potential biomarkers for the diagnosis and monitoring of the progression of SLE.
Interestingly, the 25 miRNAs including miR-146a, miR-16 and miR-21, which were over-expressed in pSS patients, were found to be elevated in SLE group, as well.
We propose that miR-21 has a pluripotent role, serving to link distinct lymphocyte signaling pathways and acting as a "rheostat" for signals that promote B and T cell activation in lupus.
MiR-21 could serve as predictor of disease progression, while MiR-196a emerges as a novel valuable biomarker to predict both SLE risk and progression, this would be a critical tool for personalizing therapy and to avoid irreversible organ damage associated with SLE.
Silencing of miR-21 reversed the activated phenotype of T cells from patients with SLE--namely, enhanced proliferation, interleukin 10 production, CD40L expression and their capacity to drive B cell maturation into Ig-secreting CD19+CD38(hi)IgD-(plasma cells.
Additionally, inhibition of miR-21 and miR-148a expression in CD4+ T cells from patients with lupus could increase DNMT1 expression and attenuate DNA hypomethylation.