SUMO2 and breast cancer: The anti-SUMO-2/3 antibody recognizes these unique higher molecular weight bands (Figure 1c lane 3), which line up with the bands in the anti-C/EBPbeta immunoblots (Figure 1c, lanes 6 and 9), thus demonstrating that endogenous C/EBPbeta1 is sumoylated in breast cancer cell lines.