Abstract: Objective To investigate the expression of microRNA-7(miR-7) in peripheral blood of patients with systemic lupus erythematosus(SLE) and its clinical significance. Methods Twenty patiens with SLE and twenty healthy controls(HCs) matched with age and gender were enrolled in this study. Real time quantitative PCR was used to detect the expression of miR-7 in peripheral blood mononuclear cells(PBMC) ,B cells,T cells and monocyte of SLE patients and HCs. PTEN mRNA expression levels were also evaluated by real time quantitative PCR. Flow cytometer was used to detect the proliferation ability of B cells, which transfected with miR-7 precursor or inhibitor and then elvaluated bioinformatics prediction and dual luciferase report gene assay system were performed to identify miR-7 targets. Results The expression of miR-7 in SLE patients was significantly higher than that in HCs(p<0.01). PTEN was one of target genes of miR-7. The B cell transfected with miR-7 precursor had reduced expression of PTEN and promoted proliferation of B cell（p<0.05）．In contrast, the opposite effect was observed with the miR-7 inhibitor transfection. Conclusions: miR-7 was involved in the pathogenesis of SLE by regulating the PTEN expression and B cell proliferation.It may be a potential therapeutic target for SLE.

Key words: Systemic lupus erythematosus, microRNA-7, PTEN