MicroRNA-143 targets MAPK3 to regulate the proliferation and bone metastasis of human breast cancer cells.

MicroRNAs (miRs) have shown tremendous potential to act as therapeutic targets for cancer treatment. In this context, the present study was designed to investigate the potential of miR-143 in the treatment of breast cancer. Results showed that miR-143 to be significantly (P < 0.05) downregulated in breast cancer tissues and cell lines. The miR-143 has inhibitory effect on CAMA-1cell growth which was manifested as significant (P < 0.05) decline in loss of viability of cancer cells. The loss of cell viability was revealed to be due to the induction of apoptotic cell death as evident from acridine orange/ethidium bromide (AO/EB) and 4',6-diamidino-2-phenylindole (DAPI) staining assays. The apoptotic cell percentage was found to be 35.7% in miR-143 mimics transfected in comparison to 6.4% in miR-NC transfected cells. The western blot analysis showed that miR-143 caused enhancement in Bax and suppression in Bcl-2 expression in CAMA-1 cells. The miR-143 also suppressed the bone metastasis of the CAMA-1 cells by suppressing the expression of Jag1 and deactivation of the Rho-signalling pathway. The transwell assays also showed considerable anti-metastatic effects of miR-143 on CAMA-1 cells. Taken together, miR-143 has growth inhibitory anti-metastatic effect on breast cancer and thus may prove beneficial in breast cancer treatment.