Single-cell gene expression profile (scRNA-seq) of CD34+ cells isolated from MPN patients with different degrees of BM fibrosis, revealed that—regardless of the MPN subtype—overt-fibrotic patients were clustered together and enriched in genes involved in pro-inflammatory pathways (TNFα, NF-KB, MIP2a, and MIP2b), including CXCL8. The gene discussed is TNF; the disease is myeloproliferative neoplasm.