Targeting of TLE3 by miR-3677 in human breast cancer promotes cell proliferation, migration and invasion

Numerous studies have indicated an important function of microRNAs (miRs) in breast cancer (BC) progression, oncogenesis and metastasis. However, the function of miR-3677, which has been revealed to be upregulated in BC [The Cancer Genome Atlas (TCGA) data], has not been investigated to date. In the present study, miR-3677 was revealed to be upregulated in BC as determined using TCGA. miR-3677 was significantly upregulated in BC tissues and cell lines compared with those noted in adjacent non-cancerous tissues and primary normal breast cells (P<0.05). The overexpression of miR-3677 promoted the cell proliferation, migration and invasion of BC cells. Using bioinformatics algorithms and luciferase assays, a novel target gene for miR-3677, namely transducin-like enhancer of Split3 (TLE3), was identified. Silencing of TLE3 in miR-3677-transfected BC cells suppressed their proliferation and migration. An inverse correlation was observed between miR-3677 and TLE3 expression levels in human BC tissues. In conclusion, the present study demonstrated that miR-3677 promoted BC cell proliferation, migration and invasion by inhibiting TLE3 expression, which provided a novel mechanism and a promising therapeutic target for patients with BC.