Effect of ionomycin, NaCl, and TGF-β on miRNA and mRNA expression and rsmiR-140 activity. The effect of increasing calcium flux (ionomycin), hypertonic stress (NaCl) and TGF-β on A) WWP2, B) miR-140 and C) IGFBP5 expression in human osteoarthritic chondrocytes (n = 7 to 12), and on D) the miR-140 regulatory sequence (rsmiR-140) in SW1353 cells (n = 6 to 9). E) Effect of silencing NFAT3 and NFAT5 on TGF-β expression in human osteoarthritic chondrocytes (n = 5). Effect of specific mutations of F) NFAT3 (−234 bp GGAAA to GGTAC) and G) SMAD3 (−195 bp CAGA to TACC) binding sites on rsmiR-140 activity in SW1353 (n = 10). Each control (untreated cells) was assigned an arbitrary value of 1 and the effect of the treatment evaluated as fold change over control. P values were assessed by the one-sample t-test, comparing treated chondrocytes to the controls or as underlined. miRNA, microRNA; TGF-β, transforming growth factor β.