Figure 1

SB-216763 promotes nuclear accumulation of Y-phospho -catenin and BC-CML cell growth. (A) Proliferation of Ku812 and fresh BC cells treated with the indicated doses (M) of SB-216763 for 24 h. Errors bars indicate s.d. of triplicate experiments. (B) GSK3 (IP: GSK3) was immunoprecipitated from Ku812 (a and b) and BC (c and d) cells treated with DMSO (-) or 5 M SB-216763 (+) for 2 h and immunoblotted with an anti-GSK3 antibody or an antibody against its phospho-Y216 residue. -Catenin was also shown. (C) Upon 8 h of treatment with 5 M SB-216763, whole lysates from BC cells were analyzed for total -catenin levels with a C-terminal antibody (C-Term). -Catenin was also probed with two antibodies recognizing its specific S/T-unphospho- (nonp-S/T) or phosphorylated (p-S/T) form. Total -actin levels were indicated as a loading control. (D) Nuclear (N) and cytosolic (C) extracts from Ku812 cells cultured with DMSO (-) or 5 M SB-216763 (+) for 8 h were analyzed with antibodies against -catenin, its specific S/T-nonphospho form (nonp-S/T), nuclear Lamin B and cytoplasmic IkB. (E, F) Nuclear (N) and cytosolic (C) extracts of Ku812 cells treated as described above were immunoprecipitated with an anti--catenin (IP: -cat, E) or an anti-phosphotyrosine (IP: p-Y, F) antibody and then immunoblotted as indicated (HC=heavy chain of IgG antibody used for immunoprecipitation).