MMP9 and gastric cancer: Nobiletin (Nob), a poly methoxy flavonoid extracted from Tangerine Peel, has been shown to inhibit MMP-9 activity in a concentration-dependent manner and to significantly reduce the total weight and number of disseminated nodules in a SCID mouse model (0.07g vs. 0.78g, p = 0.0059; 7.5 vs. 69.3/body, p = 0.0001), thereby inhibiting the proliferation of TMK-1 cell with peritoneal disseminated nodule formation, which is beneficial in preventing GC metastasis (Minagawa et al., 2001).