Overexpression of microRNA-29b induces apoptosis of multiple myeloma cells through down regulating Mcl-1

► MicroRNAs (miRNAs) can be tumor suppressors or oncogenes, but have an unclear role in multiple myeloma (MM). ► miRNA-29b was downregulated in MM patient bone marrow samples and cell lines. ► Bioinformatics showed perfect complementarity between miRNA-29b and the Mcl-1 3′UTR. ► miR-29b inhibited Mcl-1 protein expression and induced apoptosis in MM cells. ► This was reversed by miR-29b re-expression using an expression vector, which activated caspase-3.