MMP9 and fibrosarcoma: Moreover, treatment of Wehi-164 fibrosarcoma cells with aqueous extract of spearmint led to significant reduction in MMP-2/MMP-9 activity in a dose-dependent manner, as there was no detectable activity of MMP-2/MMP-9 in Wehi-164 cells treated with 10 mg/mL of the extract after 24, 48, and 72 h [151].