SENP3 upregulates the transcription of N-cadherin through de-SUMOlyation of FOXC2(A) Luciferase reporter assay in HEK293T cells co-transfected with the vector/N-cadherin promoter reporter and different doses of FOXC2. Relative luciferase activity (RLA) was shown as mean±SEM of three independent experiments. (B) The constructs of a series of N-cadherin promoter reporter with various truncations (left) and luciferase reporter assay (right) in HEK293T cells that were co-transfected with the vector/the reporter truncates and FOXC2. (C) Flag ChIP assay using the antibody against Flag and the primer of the N-cadherin promoter region −428/−209 in HEK293T cells that were transfected with the Flag-tagged vector (F-vector) / Flag-tagged wild-type FOXC2 (F-FOXC2). (D, E) Luciferase reporter assay (left) and Flag ChIP (right) in HEK293T cells that were transfected with F-FOXC2 /SUMO-less mutant of FOXC2 (F-FOXC2K214R) (D), or together with wild-type/dominant negative mutant of SENP3 (E). Both assays were repeated three times and the results were shown as mean±SEM. **: P < 0.01; ***: P<0.001. (F) The N-cadherin protein levels in the stable cell lines SGC7901-MOCK and SGC7901-SENP3 that were transiently transfected with FOXC2. (G) The SENP3 and N-cadherin protein levels in the representative gastric cancer tissue lysates.