MMP9 and cancer: Fucoidan derived from U. pinnatifida sporophylls inhibit hypoxia in cancer cells through nuclear translocation, activity of HIF-1α and reduction in the levels of phosphorylated-PI3K (p-PI3K), p-Akt, p-mTOR, p-ERK, NF-κB, MMP-2, and MMP-9, but increased TIMP-1 levels.