Immune activation and microenvironmental crosstalk in hairy cell leukemia

Area of Science:

• Hematology
• Cancer Biology
• Immunology

Background:

• Hairy cell leukemia (HCL) is an indolent B-cell malignancy often treated with nucleoside analogs.
• Despite initial remissions, patients frequently relapse due to resistance mechanisms.
• The leukemic microenvironment, especially in bone marrow and spleen, protects hairy cells.

Purpose of the Study:

• To review how the leukemic microenvironment contributes to therapeutic resistance in HCL.
• To explore the role of stromal interactions, extracellular matrix, and immune evasion.
• To highlight emerging strategies targeting microenvironmental support for improved HCL treatment.

Main Methods:

• Review of existing literature on HCL pathogenesis and treatment resistance.
• Analysis of signaling pathways (BCR, MAPK) and microenvironmental factors.
• Identification of novel therapeutic targets and strategies.

Main Results:

• Leukemic microenvironments provide retention signals (CXCR4, adhesion) and cytokine support.
• Immune evasion mechanisms within niches sustain leukemic cell survival and minimal residual disease.
• Stromal interactions, ECM remodeling, and immune surveillance disruption reinforce resistance.

Conclusions:

• The specialized microenvironment is central to HCL therapeutic resistance and relapse.
• Disrupting microenvironmental support is a promising strategy to overcome resistance.
• Emerging therapies targeting chemotaxis, adhesion, and immune checkpoints aim to improve HCL remission depth and durability.