Figure 7.

MLN4924 induces p21, p27, Deptor and IkBa accumulation that are important for sorafenib sensitization. (A) LM3 cells were treated with different concentrations of sorafenib (Soraf) in the presence or absence of MLN4924 (MLN) for 48 h, followed by western blot analysis. (B-D) LM3 cells were transfected with NF-κB p65 siRNA (siNFκB p65) or treated with mTOR inhibitor rapamycin (100 nM). Forty-eight hours later, a portion of cells were harvested for (B) western blot analysis or (C) cell proliferation using CCK-8. (D) Other cells were used for Transwell assay to determine the migratory ability. Magnification at ×100. (E) MLN4924 inhibits CRL/SCF E3 ubiquitin ligase activity by inhibiting NAE resulting in the accumulation of p21/p27 to inhibit proliferation and migration; IκBα to inhibit NF-κB, and block cell migration by decreasing N-cadherin and vimentin; Deptor to inhibit mTORC1 activation thus inhibiting cell proliferation and migration. Arrows represent promotion events, blunt arrows indicate suppression events. *P<0.05; **P<0.01; ***P<0.001. CCK-8, Cell Counting Kit-8; mTOR, mammalian target of rapamycin; NAE1, NEDD8-activating enzyme 1; CRL, Cullin-Ring ligase; SCF, Skp1-Cullin1-F box; MMP9, metalloproteinase 9.