Several reports have suggested the oncogenic property of this miRNA: interleukin (IL)-6 induces miR-21 expression in a strictly STAT3-dependent manner, ectopic expression of miR-21 in MM cells decreases apoptosis in the absence of IL-6, and miR-21 inhibition suppresses MM cell growth [14,18,19]. This evidence concerns the gene IL6 and Miyoshi myopathy.