MiR-1228 promotes breast cancer cell growth and metastasis through targeting SCAI protein

Breast cancer is the most common cancer in women around the world. However, the molecular mechanisms underlying breast cancer pathogenesis are only partially understood. Here, in this study, we found that miR-1228 was up-regulated in breast cancer cell lines and tissues. Ectopic expression of miR-1228 mimics leads to promoted cell growth, invasion and migration. Using bioinfomatic analysis and 3'UTR luciferase reporter assay, we determined SCAI can be directly targeted by miR-1228, which can down-regulate endogenous SCAI protein level. Furthermore, our findings demonstrate that SCAI was down-regulated in breast cancer cell lines and tissues. Rescue experiment demonstrated that miR-1228 promoted cell growth is attenuated by over-expression of MOAP1 and miR-1228 promoted cell invasion and migration can be attenuated by over-expression of SCAI. Taken together, this study provides evidences that miR-1228 serves as an oncogene to promote breast cancer proliferation, invasion and migration, which may become a critical therapeutic target for breast cancer treatment.