MMP9 and breast cancer: Similarly, intraperitoneal administration of pectolinarigenin inhibited breast cancer metastasis into lungs in Balb/c mice injected with 4T1 mouse breast cancer cells and suppressed migration and invasion of MCF-7, MDA-MB-231, and 4T1 breast cancer cells in vitro mediated by an inhibition of MMP-2, MMP-9, and p-STAT3 expression and upregulation of TIMP-2 [69].