CRLF2 and leukemia: To identify putative “adaptive pathways” apparent in Eμ-Crlf2/Jak2R683G leukemia cells with chronic relative to acute Jak2 depletion, gene set enrichment analysis (GSEA) was performed against all publicly available oncogenic signature data sets (C6, Broad Institute Molecular Signatures Database [MSigDB]) (Subramanian et al. 2005).