Recent studies show that many microRNAs (miRNAs) are found to play important roles in breast cancer, however, most of miRNAs are not investigated completely. In the present study, significant down-regulation of miR-520a-3p was found in the breast cancer tissues and cell lines. The restoration of miR-520a-3p expression in breast cancer cells could inhibit cell proliferation, migration and invasion. In addition, miR-520a-3p was able to induce breast cancer cell apoptosis. Luciferase assay was used to confirm that CCND1 and CD44 were the direct target genes of miR-520a-3p. The ectopic expression of miR-520a-3p repressed CCND1 and CD44 expression on post-transcriptional levels in breast cancer cells. This study suggests that miR-520a-3p may act as an optional method for breast cancer therapy.
Keywords: CCND1; CD44; breast cancer; metastasis; miR-520a-3p; proliferation.