Proteostasis Disruption in Inherited Bone Marrow Failure Syndromes.

Abstract

Inherited bone marrow failure syndromes (IBMFS) are genetic disorders of impaired hematopoiesis that manifest in childhood with both cytopenias and extra-hematologic findings. While several IBMFS are categorized as ribosomopathies due to shared underlying ribosomal dysfunction, there is a broader disruption of the protein homeostasis (proteostasis) network across both classic and emerging IBMFS. Precise regulation of the proteostasis network, including mechanisms of protein synthesis, folding, trafficking, and degradation as well as associated stress response pathways, has emerged as essential for maintaining hematopoietic stem cell (HSC) function, providing new potential mechanistic insights into IBMFS pathogenesis. Furthermore, the varied clinical trajectories of patients with IBMFS with possible divergent outcomes of malignancy and spontaneous remission may reflect developmental and temporal changes in proteostasis activity and be driven by strong selective pressures to restore proteostasis. These new insights are spurring fresh therapeutic approaches to target proteostasis. Thus, further evaluation of proteostasis regulation and the consequences of proteostasis disruption in IBMFS could aid in developing new biomarkers, therapeutic agents, and preventative approaches for patients.