PIM1 and breast cancer: To provide additional evidence that the 200-kDa band co-precipitated and phosphorylated by Pim-1 from TPA-induced BC-3 cells (Figure 3C) is indeed LANA we performed a competition experiment where GST-N-LANA and/or GST-C-LANA were added as competing substrates into the cell extract prior to Pim-1 immunoprecipitation from BC-3 cells that had been treated with TPA for 48 h.