Inflammation as a Keystone of Bone Marrow Stroma Alterations in Primary Myelofibrosis

Area of Science:

• Hematology
• Oncology

Background:

• Primary myelofibrosis (PMF) is a complex clonal neoplasm characterized by bone marrow stroma alterations, including fibrosis, neoangiogenesis, and osteosclerosis.
• Current understanding focuses on mutations in hematopoietic cells driving myeloproliferation, with stromal changes often considered secondary to cytokine release.
• Despite targeted therapies reducing inflammation, PMF remains largely incurable without stem cell transplantation, highlighting unmet therapeutic needs.

Purpose of the Study:

• To explore the functional involvement of bone marrow stromal cells in PMF pathogenesis.
• To propose a hypothesis on the self-perpetuating inflammatory role of the stroma in PMF.
• To advocate for novel therapeutic strategies targeting the bone marrow stroma.

Main Methods:

• This is a review article, synthesizing existing literature and proposing new hypotheses.
• Analysis of current understanding of PMF pathogenesis, including genetic mutations and cytokine profiles.
• Conceptual framework development regarding stromal cell imprinting and independent inflammation.

Main Results:

• Current therapies targeting hematopoietic clones reduce inflammation but do not resolve the underlying stromal pathology.
• Proposed hypothesis: Clonal hematopoietic cells imprint the bone marrow stroma, leading to a state of "independent" inflammation.
• This imprinted stroma may create a self-sustaining inflammatory loop, contributing to PMF progression.

Conclusions:

• The bone marrow stroma plays a critical, potentially independent, role in PMF pathogenesis.
• Targeting the altered stroma, in addition to hematopoietic clones, is crucial for effective PMF treatment.
• Future research should focus on developing therapies that address stromal contributions to PMF's inflammatory environment.