As shown in Fig 4, the level of reversion of the HS-5-induced protection to Vorinostat and Ruxolitinib with SP600125 and LY294002 varied among primary MPN cells (MPN patients #1, #3 and #6 failed to revert HS-5 induced protection with SP600125 and LY294002), which might reflect inter-patient variability and might also suggest that other signalling pathways could be activated in these patients by stromal cells, such as MEK-ERK or NF-κB (Fig 2). This evidence concerns the gene NFKB1 and myeloproliferative disorder.