MicroRNA miR-151 expression profiling study and mRNA correlation analysis in circulating monocyte were identified to be related with the etiology of osteoarthritis

Abstract MiRNAs have been implicated important in the etiology of various diseases. Osteoarthritis is a relative-immune disease with chronic in local knuckle and cellular immunity is more important, it is characterized by cytokine included T cell and monocytes. From that, we explore the relationship between the expression profile of microRNA miR-151 in circulating monocytes and the correlation analysis of mRNA correlation with the etiology of osteoarthritis.We first explored differential expression of miRNAs in human circulating monocytes between 20 OA patients and 20 normal. Expression level of each miRNA was normalized with RNU48.Differential miRNAs were selected by t-test and miR-151 was up-regulated (P = 0.015) in two groups, furthermore, it was confirmed in individual assays with qRT-PCR. Moreover, we investigated mRNA profilings in human circulating monocytes isolated with the subjects used in miRNA array analysis. Pearson correlation analysis between the expression level of miR-151 and the mRNA array expression data was performed.We found significant correlation of miR-151 with TNFSR11 (r= -0.87, P = 0.000176), LRCH1 (r = 0.73, P = 0.0087) and FZD5 (r = 0.72, P = 0.02143) genes. LRCH1 and FZD5 genes are also predicted as the targets of miR-151( http://www.targetscan.org ). LRCH1 and FZD5 were also down-regulated expressed in OA patients compared with normal person. Genetic epidemiologic studies have shown the association of LRCH1 gene with human osteoarthritis. Expression profiling studies also found the relationship between FZD5 gene and human osteoarthritis. MiR-151 may affect the differentiation of monocytes by regulating the expression of LRCH1 and FZD5 genes.