In the current study, we investigated the functional role of miR-145 in HGSOC, both in vitro and in vivo. We found that overexpression of miR-145 in ovarian cancer cells significantly suppressed proliferation, migration and invasion in vitro and inhibited tumor growth and metastasis in vivo. Furthermore, metadherin (MTDH), an oncogene that was highly expressed in breast cancer[13] and ovarian cancer[14], was identified as a direct target of miR-145. This evidence concerns the gene MTDH and breast cancer.