Summary of animal models of myelodysplastic syndrome

Understanding MDS stem cells: Advances and limitations

In work spanning several decades, extensive studies have focused on the properties of malignant stem cells that drive the pathogenesis of acute myeloid leukemia (AML). However, relatively little attention has been devoted to several serious myeloid malignancies that occur prior to the onset of frank leukemia, including myelodysplastic syndrome (MDS). Like leukemia, MDS is hypothesized to arise from a pool of immature malignant stem and progenitor cells (MDS-SCs) that serve as a reservoir for disease evolution and progression1. While multiple studies have sought to identify and characterize the biology and vulnerabilities of MDS-SCs, yet translation of scientific concepts to therapeutically impactful regimens has been limited. Here, we evaluate the currently known properties of MDS-SCs as well as the post-transcriptional mechanisms that drive MDS pathogenesis at a stem and progenitor level. We highlight limits and gaps in our characterization and understanding of MDS-SCs and address the extent to which the properties of MDS-SC are (and can be) inferred from the characterization of LSCs.

Mesenchymal Stem Cells in Myelodysplastic Syndromes and Leukaemia

Mesenchymal stem cells (MSCs) are one of the main residents in the bone marrow (BM) and have an essential role in the regulation of haematopoietic stem cell (HSC) differentiation and proliferation. Myelodysplastic syndromes (MDSs) are a group of myeloid disorders impacting haematopoietic stem and progenitor cells (HSCPs) that are characterised by BM failure, ineffective haematopoiesis, cytopenia, and a high risk of transformation through the expansion of MDS clones together with additional genetic defects. It has been indicated that MSCs play anti-tumorigenic roles such as in cell cycle arrest and pro-tumorigenic roles including the induction of metastasis in MDS and leukaemia. Growing evidence has shown that MSCs have impaired functions in MDS, such as decreased proliferation capacity, differentiation ability, haematopoiesis support, and immunomodulation function and increased inflammatory alterations within the BM through some intracellular pathways such as Notch and Wnt and extracellular modulators abnormally secreted by MSCs, including increased expression of inflammatory factors and decreased expression of haematopoietic factors, contributing to the development and progression of MDSs. Therefore, MSCs can be targeted for the treatment of MDSs and leukaemia. However, it remains unclear what drives MSCs to behave abnormally. In this review, dysregulations in MSCs and their contributions to myeloid haematological malignancies will be discussed.

A research review of experimental animal models with myelodysplastic syndrome

Myelodysplastic syndrome (MDS) consists of a group of hematologic tumors that are derived from the clonal proliferation of hematopoietic stem cells, featuring abnormal hematopoietic cell development and ineffective hematopoiesis. Animal models are an important scientific research platform that has been widely applied in the research of human diseases, especially tumors. Animal models with MDS can simulate characteristic human genetic variations and tumor phenotypes. They also provide a reliable platform for the exploration of the pathogenesis and diagnostic markers of MDS as well as for a drug efficacy evaluation. This paper reviews the research status of three animal models and a new spontaneous mouse model with MDS.