Oncogenic role of microRNA-20a in human multiple myeloma.

microRNAs are important in cancer biogenesis and development. However, their underlying mechanisms in multiple myeloma (MM) are barely characterized. microRNA-20a (miR-20a) is a member of the microRNA-17-92 cluster. It has been implicated in various cancers, regulating the proliferation and invasion of cancer cells in vitro. Compared with healthy donors, it also has been reported to be elevated in plasma of MM patients. Here, we investigated the function of miR-20a. Our results showed that it promotes proliferation and inhibits apoptosis of MM cells in vitro by inhibiting early growth response protein 2. The effects of miR-20a were also evaluated in MM xenograft models of SCID/NOD mice. Apparent antitumor activity was achieved in xenograft mice injected with miR-20a inhibitor, while mimics of miR-20a significantly promoted tumor growth. These data indicate that miR-20a plays a crucial role in the biology of MM and represents a potential target for novel therapies for MM patients.