Compared with PV patients, ET patients had lower levels of G-CSF, HGF, IFN-γ, IL-10, and IL-17a in the BM niche, while PMF patients presented lower levels of CCL2, CCL5, CXCL12, G-CSF, GM-CSF, HGF, IFN-γ, IL-1β, IL-10, IL-17a, IL-12p70, M-CSF, TNF-α, and VEGF. This evidence concerns the gene CCL2 and acquired polycythemia vera.