Current therapeutic approaches for patients with myelodysplastic syndromes

Proposals for revised IWG 2018 hematological response criteria in patients with MDS included in clinical trials

The heterogeneity of myelodysplastic syndromes (MDSs) has made evaluating patient response to treatment challenging. In 2006, the International Working Group (IWG) proposed a revision to previously published standardized response criteria (IWG 2000) for uniformly evaluating clinical responses in MDSs. These IWG 2006 criteria have been used prospectively in many clinical trials in MDSs, but proved challenging in several of them, especially for the evaluation of erythroid response. In this report, we provide rationale for modifications (IWG 2018) of these recommendations, mainly for "hematological improvement" criteria used for lower-risk MDSs, based on recent practical and reported experience in clinical trials. Most suggestions relate to erythroid response assessment, which are refined in an overall more stringent manner. Two major proposed changes are the differentiation between "procedures" and "criteria" for hematologic improvement-erythroid assessment and a new categorization of transfusion-burden subgroups.

Specific plasma autoantibody reactivity in myelodysplastic syndromes

Increased autoantibody reactivity in plasma from Myelodysplastic Syndromes (MDS) patients may provide novel disease signatures, and possible early detection. In a two-stage study we investigated Immunoglobulin G reactivity in plasma from MDS, Acute Myeloid Leukemia post MDS patients, and a healthy cohort. In exploratory Stage I we utilized high-throughput protein arrays to identify 35 high-interest proteins showing increased reactivity in patient subgroups compared to healthy controls. In validation Stage II we designed new arrays focusing on 25 of the proteins identified in Stage I and expanded the initial cohort. We validated increased antibody reactivity against AKT3, FCGR3A and ARL8B in patients, which enabled sample classification into stable MDS and healthy individuals. We also detected elevated AKT3 protein levels in MDS patient plasma. The discovery of increased specific autoantibody reactivity in MDS patients, provides molecular signatures for classification, supplementing existing risk categorizations, and may enhance diagnostic and prognostic capabilities for MDS.

Targeting IRAK1 as a therapeutic approach for myelodysplastic syndrome

Myelodysplastic syndromes (MDSs) arise from a defective hematopoietic stem/progenitor cell. Consequently, there is an urgent need to develop targeted therapies capable of eliminating the MDS-initiating clones. We identified that IRAK1, an immune-modulating kinase, is overexpressed and hyperactivated in MDSs. MDS clones treated with a small molecule IRAK1 inhibitor (IRAK1/4-Inh) exhibited impaired expansion and increased apoptosis, which coincided with TRAF6/NF-κB inhibition. Suppression of IRAK1, either by RNAi or with IRAK1/4-Inh, is detrimental to MDS cells, while sparing normal CD34(+) cells. Based on an integrative gene expression analysis, we combined IRAK1 and BCL2 inhibitors and found that cotreatment more effectively eliminated MDS clones. In summary, these findings implicate IRAK1 as a drugable target in MDSs.

Update on the science of myelodysplastic syndromes

Scientific research is only just beginning to shed light on the pathobiology underlying the various subtypes of myelodysplastic syndromes (MDS), a heterogeneous group of clonal stem cell disorders characterized by cytopenias that can progress to acute myeloid leukemia. Increased understanding of the disease and prognostic implications of specific clinical features has aided in the development of prescribing guidelines and new treatments for MDS. Because oncology nurses have frequent interactions with patients during diagnostic and therapeutic evaluations, an understanding of the science behind disease classification, prognostic scoring, and the goals of treatment for low- and high-risk disease is important to answer questions regarding diagnostic results, treatment outcomes, and adverse event monitoring.

Myelodysplastic syndrome and histone deacetylase inhibitors: "to be or not to be acetylated"?

Myelodysplastic syndrome (MDS) represents a heterogeneous group of diseases with clonal proliferation, bone marrow failure and increasing risk of transformation into an acute myeloid leukaemia. Structured guidelines are developed for selective therapy based on prognostic subgroups, age, and performance status. Although many driving forces of disease phenotype and biology are described, the complete and possibly interacting pathogenetic pathways still remain unclear. Epigenetic investigations of cancer and haematologic diseases like MDS give new insights into the pathogenesis of this complex disease. Modifications of DNA or histones via methylation or acetylation lead to gene silencing and altered physiology relevant for MDS. First clinical trials give evidence that patients with MDS could benefit from epigenetic treatment with, for example, DNA methyl transferase inhibitors (DNMTi) or histone deacetylase inhibitors (HDACi). Nevertheless, many issues of HDACi remain incompletely understood and pose clinical and translational challenges. In this paper, major aspects of MDS, MDS-associated epigenetics and the potential use of HDACi are discussed.

Review of stem-cell transplantation for myelodysplastic syndromes in older patients in the context of the Decision Memo for Allogeneic Hematopoietic Stem Cell Transplantation for Myelodysplastic Syndrome emanating from the Centers for Medicare and Medicaid Services

Myelodysplastic syndromes (MDS) comprise a heterogeneous group of clonal hematopoietic stem-cell disorders that result in varying degrees of cytopenia and risk of transformation into acute leukemia. Allogeneic stem-cell transplantation (SCT) is the only known cure for this disease. The treatment is routinely used for younger patients, but only a minority of patients older than the age of 60 undergo this procedure. The overall MDS incidence is 3.3 per 100,000, but the incidence in patients older than age 70 is between 15 and 50 per 100,000. The median age at presentation is 76 years. Medicare-age patients 65 or older represent 80% of the total population receiving an MDS diagnosis. In the United States, one of the obstacles to SCT for older patients with MDS has been lack of third party reimbursement. On August 4, 2010, the Centers for Medicare and Medicaid Services released their Decision Memo for Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) for Myelodysplastic Syndrome. This memo states: "Allogeneic HSCT for MDS is covered by Medicare only for beneficiaries with MDS participating in an approved clinical study that meets the criteria below…. " In this review, we will summarize what is known regarding the role of allogeneic SCT in older patients as well as other elements that should be included within clinical trials that can provide the evidence necessary to demonstrate that allogeneic SCT should be a covered benefit for Medicare beneficiaries.

The revolution of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are clonal disorders of the hematopoietic system with resultant cytopenias and shortened survival. Better recognition of MDS and an aging population, some of whom have been treated with chemotherapy and radiation therapy for other cancers, is largely responsible for the growing incidence of this malignancy, which is divided into lower- and higher-risk subtypes. Erythropoiesis-stimulating agents are the first-line treatment options for patients with lower-risk MDS and symptomatic anemia or for those requiring transfusion support. Lenalidomide has been successfully used for patients with the del(5q) chromosomal abnormality who are also transfusion dependent. Hypomethylating agents, such as azacitidine and decitabine, are indicated for patients with higher-risk disease, with azacitidine demonstrating a survival advantage. Hematopoietic stem cell transplantation (HSCT) is a curative therapeutic approach available to less than 5% of patients with MDS. Combination therapies and newer single agents targeting the important cellular pathways are being explored for treatment of MDS with promising results.