Fig. 5

p53 is critical for BATF2-mediated inhibition of ERK signaling. a p53 expression in stably transfected HGC-27 and SNU-216 cells was determined by western blotting. b p53 expression in stably transfected HGC-27 and SNU-216 cells was determined by qRT-PCR (ns: no significant difference). c Immunofluorescence (IF) staining indicating the colocalization of BATF2 (green) and p53 (red) together with DAPI (blue) in GC cells. Scale bars = 100 μm. d-e A co-immunoprecipitation (co-IP) assay was performed to analyze the interaction between BATF2 and p53 in SNU-216 cells. f The half-life of p53 protein in HGC-27 cells was analyzed following treatment with cycloheximide (CHX, 25 μg/ml) at the indicated time points. g Stably transfected HGC-27 and SNU-216 cells were treated with or without 10 mmol/l MG132 for 6 h, p53 was immunoprecipitated with an anti-p53 antibody, and the poly-ubiquitination of p53 was examined by western blotting using an anti-ubiquitin antibody. IP: immunoprecipitation; Ub-p53: poly-ubiquitinated of p53. h-j The effect of BATF2 overexpression on HGC-27 cell proliferation, migration and invasion was rescued by transfection with p53 siRNA (**P < 0.01; ns: no significant difference). k The protein levels of p53, p-ERK, MMP2, MMP9 and cyclinD1 in stably transfected HGC-27 cells treated with p53-siRNA or NC-siRNA were determined by western blotting