MMP9 and breast cancer: To see the effect of HSP on human epidermal growth factor receptor 2 (HER2), researchers performed a study on HER2 overexpressed breast cancer cell (MCF-7/HER2) and MCF-7/EV cell and observed that at 95 μM concentration, HSP decreased HER2, MMP-9, Rac1 expression, lamellipodia formation, and arrested cell cycle at G2/M phase; therefore reducing cell viability, invasion, migration and promoting apoptosis [61].