To validate down-regulation of miR-21 by BB and to investigate the effect of exogenous IL6 on BB-modulated miRNA-21 expression in MM, RPMI-8266 and U226 cells were treated without or with 75 μM or 120 μM BB, respectively, in the absence or presence of IL6 (0.5 ng/ml). Here, IL6 is linked to Miyoshi myopathy.