TNF and myeloproliferative disorder: Within this marrow niche, the release of high levels of inflammatory cytokines such as tumor necrosis factor α (TNFα) and tumor growth factor β1 (TGFβ1) contribute to the dominance of malignant clones at the expense of the normal hematopoietic cells [62] and is associated with the increased deposition of reticulin and collagen fibers leading to the development of extensive marrow fibrosis, a common finding for MPN patients [63].