LINC00665 Stimulates Breast Cancer Progression via Regulating miR-551b-5p

INTRODUCTION: Long intergenic non-protein coding RNA 665 (LINC00665) has been revealed to contribute cancer progression in many cancer types including liver and gastric cancer. However, the roles of LINC00665 in breast cancer (BC) remain to be explored. METHODS: We explored LINC00665 expression in BC tissues and normal tissues at GEPIA. Then, its expression in BC cells (HCC-1937, MDA-MB-231, and MCF-7) and normal cells (MCF10A) was analyzed with qRT-PCR. In addition, the mechanisms of LINC00665 in BC were explored using bioinformatic analyses, luciferase activity reporter assay, RNA pull-down assay, and rescue experiments. RESULTS: We showed LINC00665 expression was significantly increased in both BC tissues and cells. The knockdown of LINC00625 significantly inhibits BC cell growth and promotes cell apoptosis in vitro, while the overexpression of LINC00625 has the opposite effects on BC progression. LINC00665 could affect BC progression via regulating miR-551b-5p. DISCUSSION: Taken together, our study showed that the LINC00665/miR-551b-5p axis was involved in the progression of BC.