Metastasis inhibition by BRMS1 and miR-31 replacement therapy in claudin-low cell lines

The growing trend of research demonstrates that dynamic expression of two metastasis repressor classes (metastasis suppressor genes and anti-metastatic miRNA) has a close relationship with tumor invasion and metastasis. Using different strategies, it was revealed that cellular levels of miR-31 and Breast cancer Metastasis Suppressor1 (BRMS1) protein, which are among the most significant modulators of metastasis, have a correlation with the cell’s capability for invading and metastasizing; cells containing higher levels of miR-31 or BRMS1 were less metastatic. This project was carried out to determine whether the combinations of miR-31 and BRMS1 genes are able to enhance the capability of repressing the claudin-low breast cancer cell (MDA-MB-231) invasion. This study used a restoration-based approach by miR-31 mimic and optimized BRMS1 gene sequences, which were cloned into a chimeric construct and transfected to the MDA-M231cells. Our data revealed that the simultaneous expression of anti-metastasis miR and metastasis suppressor might inhibit migration and invasion in MDA-MB-231 cells efficiently. This combinatorial use of anti-metastatic miR and gene suggests a new therapeutic intervention for metastasis inhibition in MDA-MB-231.