Minocycline induced apoptosis and suppressed expression of matrix metalloproteinases 2 and 9 in the breast cancer MCF-7 cells.

BACKGROUND: In women, breast cancer is the second most frequent type of cancer. Looking for new and effective cancer-specific therapies with little to no adverse effects on healthy cells is critical.

OBJECTIVE: Minocycline, a second-generation tetracycline, has shown anticancer effects by targeting multiple pathways in various cancers. This study aimed to determine minocycline effects on the cell proliferation, apoptosis, and invasion of the human MCF-7 cells.

METHODS: MTT assay was used to evaluate the cytotoxicity of minocycline on the cells. Flow cytometry was performed to investigate the induction of apoptosis and the cell cycle progression. The expression levels of apoptotic and migration proteins and genes were assessed by western blotting and qRT-PCR. The scratch test was performed to evaluate the anti-migration effect of the drug.

RESULTS: The results indicated that the IC50 value of minocycline for MCF-7 cells was 36.10 µM. Minocycline treatment caused sub-G1 cell accumulation, indicating a significant apoptotic effect on the MCF-7 cells. Annexin-V/PI staining revealed a significant rise in early and late apoptotic cell percentages. Minocycline up-regulated Bax and Caspase-3 expression and down-regulated Bcl-2 and Pro-Cas3. The scratch test revealed significant anti-migration effects for minocycline. Furthermore, it caused down-regulation of MMP-2 and MMP-9 in a concentration-dependent method.

CONCLUSION: These findings further confirmed the anticancer effect of minocycline and highlighted that minocycline maybe considered as potential therapeutic agent for breast cancer treatment.