MMP9 and gastric cancer: Given that 1) matrix metalloproteinase 9 (MMP-9) promotes cell migration41, 2) MMP-9 is a known target of NFκB42 and 3) MLN4924 inactivates NFκB by causing accumulation of IκBα (Fig. 5c), we determined potential involvement of MMP-9 in cell migration and found that MLN4924 effectively inhibited expression of MMP-9 mRNA in both gastric cancer cell lines (Fig. 5d).