JAK2 amplification, expression, and activity. (A) GISTIC analysis (for all cell lines) of 9p24.1, PD-L1 and PD-L2, in the amplification peak and JAK2 in the broader amplification region. (B) JAK2 transcript abundance in HL and DLBCL cell lines and the single MLBCL cell line (left) and primary MLBCLs with 9p24.1 (PD-L1) amplification or normal copy number (right). (C) Western blot analysis of phospho- and total JAK2 in HL cell lines arranged according to 9p24.1 copy number (normal to high, left to right, as in Figure 2) and the single MLBCL cell line. (D) Intracellular phosphoflow cytometric analysis of phosphorylated STAT1 in HL and MLBCL cell lines in panel C.