NES and myeloproliferative neoplasm: In a study on the TME of MPN, we could demonstrate that there is both a reduction of sympathetic nerve fibers and, consecutive, of nestin-expressing MSC in MPN, which is linked to the effects of proinflammatory cytokines that are increased in MPN, and can be to a part reverted by administering β3-adrenergic agonists (34).