Up-regulated lnc-lung cancer associated transcript 1 enhances cell migration and invasion in breast cancer progression.

Breast cancer remains a leading cause of tumor-related deaths in the world. The pathogenesis contributing to breast cancer progression has not been fully understood. Increasing evidence suggests that long noncoding RNA (lncRNA) is implicated in various kinds of malignant cancers, including breast cancer. In the study, we attempted to explore the expression and effects of lnc-lung cancer associated transcript 1 (LUCAT1) on breast cancer development. Our results indicated that the expression of lnc-LUCAT1 was highly up-regulated in breast cancer tissues and cell lines. Over-expression of lnc-LUCAT1 enhanced cell proliferation, migration and invasion in breast cancer cell lines. Moreover, lnc-LUCAT1 was found to be a target of miR-7-5p. There was a negative correlation between lnc-LUCAT1 and miR-7-5p. The reduction of miR-7-5p was required in the augmentation of breast cancer development induced by lnc-LUCAT1 over-expression. In addition, SOX2 acted as a target of miR-7-5p. SOX2 was an oncogene in breast cancer through promoting cell proliferation, migration and invasion. The in vivo study confirmed the role of lnc-LUCAT1 in promoting tumor growth, accompanied with down-regulated SOX2 expression, whereas up-regulated miR-7-5p. Collectively, the lnc-LUCAT1/miR-7-5p-SOX2 regulatory pathway might provide a new and effective therapeutic strategy to prevent breast cancer development.