MMP9 and breast cancer: Picroside I, Kutkoside, and Kutkin isolated from Picrorhiza kurroa, a traditional Chinese herb, showed anti-invasive activity against MCF-7 breast cancer cells, and this inhibitory effect was attributed to downregulation of the activity of gelatinases (MMP-2 and MMP-9) and collagenases (MMP-1 and MMP-13) [79].