Enhancement of Breast Cancer Cell Aggressiveness by lncRNA and its Mir-675 Derivative: Insight into Shared and Different Actions.

Breast cancer is a major public health problem and the leading world cause of women death by cancer. Both the recurrence and mortality of breast cancer are mainly caused by the formation of metastasis. The long non-coding RNA , the precursor of miR-675, is involved in breast cancer development. The aim of this work was to determine the implication but, also, the relative contribution of and miR-675 to the enhancement of breast cancer metastatic potential. We showed that both and miR-675 increase the invasive capacities of breast cancer cells in xenografted transgenic zebrafish models. In vitro, and miR-675 enhance the cell migration and invasion, as well as colony formation. seems to induce the epithelial-to-mesenchymal transition (EMT), with a decreased expression of epithelial markers and an increased expression of mesenchymal markers. Interestingly, miR-675 simultaneously increases the expression of both epithelial and mesenchymal markers, suggesting the induction of a hybrid phenotype or mesenchymal-to-epithelial transition (MET). Finally, we demonstrated for the first time that miR-675, like its precursor increases the stemness properties of breast cancer cells. Altogether, our data suggest that and miR-675 could enhance the aggressiveness of breast cancer cells through both common and different mechanisms.