Epigenetic remodeling to improve the efficacy of immunotherapy in human glioblastoma: pre-clinical evidence for development of new immunotherapy approaches.

BACKGROUND: Glioblastoma multiforme (GBM) is a highly aggressive primary brain tumor, that is refractory to standard treatment and to immunotherapy with immune-checkpoint inhibitors (ICI). Noteworthy, melanoma brain metastases (MM-BM), that share the same niche as GBM, frequently respond to current ICI therapies. Epigenetic modifications regulate GBM cellular proliferation, invasion, and prognosis and may negatively regulate the cross-talk between malignant cells and immune cells in the tumor milieu, likely contributing to limit the efficacy of ICI therapy of GBM. Thus, manipulating the tumor epigenome can be considered a therapeutic opportunity in GBM. METHODS: Microarray transcriptional and methylation profiles, followed by gene set enrichment and IPA analyses, were performed to study the differences in the constitutive expression profiles of GBM vs MM-BM cells, compared to the extracranial MM cells and to investigate the modulatory effects of the DNA hypomethylating agent (DHA) guadecitabine among the different tumor cells. The prognostic relevance of DHA-modulated genes was tested by Cox analysis in a TCGA GBM patients' cohort. RESULTS: The most striking differences between GBM and MM-BM cells were found to be the enrichment of biological processes associated with tumor growth, invasion, and extravasation with the inhibition of MHC class II antigen processing/presentation in GBM cells. Treatment with guadecitabine reduced these biological differences, shaping GBM cells towards a more immunogenic phenotype. Indeed, in GBM cells, promoter hypomethylation by guadecitabine led to the up-regulation of genes mainly associated with activation, proliferation, and migration of T and B cells and with MHC class II antigen processing/presentation. Among DHA-modulated genes in GBM, 7.6% showed a significant prognostic relevance. Moreover, a large set of immune-related upstream-regulators (URs) were commonly modulated by DHA in GBM, MM-BM, and MM cells: DHA-activated URs enriched for biological processes mainly involved in the regulation of cytokines and chemokines production, inflammatory response, and in Type I/II/III IFN-mediated signaling; conversely, DHA-inhibited URs were involved in metabolic and proliferative pathways. CONCLUSIONS: Epigenetic remodeling by guadecitabine represents a promising strategy to increase the efficacy of cancer immunotherapy of GBM, supporting the rationale to develop new epigenetic-based immunotherapeutic approaches for the treatment of this still highly deadly disease.

Hypomethylating agents (HMAs) show benefit in AML rather than in intermediate/high-risk MDS based on genetic mutations in epigenetic modification (EMMs): from a retrospective study.

Since HMAs were recommended for treatments in AML and MDS, we wondered whether HMAs could provide similar benefit to AML and intermediate/high-risk MDS under the direction of next-generation sequencing. Here we retrospectively analyzed the prognosis of 176 AML and 128 intermediate/high-risk MDS patients treated with HMAs or non-HMA regimens. For AML, HMAs regimen was related to better CR rate compared with non-HMA regimen in elder cohort, while the situation was the opposite in younger cohort. In consolidation phase, EMM (+) patients could benefit from HMAs regimen. Relapsed AML patients receiving HMAs regimen rather than non-HMA regimen had better post-relapse survival. Multivariate analysis identified HMA regimen as an independent prognostic factor for OS in EMM (+) cohort. For intermediate/high-risk MDS patients not undergoing HSCT, however, HMA regimen showed no survival advantage in EMM (+) cohort and was conversely associated with shorter survival in EMM (-) cohort compared with non-HMA regimen. And among those undergoing HSCT, HMA prior to HSCT predicted poor prognosis compared with upfront HSCT regardless of the existence of EMMs. Therefore, HMAs had better therapeutic value in AML rather than in intermediate/high-risk MDS based on EMMs.

Real-world effectiveness of first-line azacitidine or decitabine with or without venetoclax in acute myeloid leukemia patients unfit for intensive therapy.

BACKGROUND: First-line treatment in patients with acute myeloid leukemia (AML) unfit for intensive therapy is the combination of a hypomethylating agent (HMA) with venetoclax (VEN). However, retrospective data confirming the benefits of this regimen outside of clinical trials have shown conflicting results. METHODS: We performed a multicenter retrospective analysis of outcomes with first-line HMA-VEN versus HMA in AML patients unfit for intensive chemotherapy. RESULTS: A total of 213 patients were included from three German hospitals (125 HMA-VEN, 88 HMA). Median overall survival in the HMA-VEN cohort was 7.9 months (95% confidence interval [CI], 5.1-14.7) versus 4.9 months (3.1-7.1) with HMA. After 1 year, 42% (95% CI, 33-54) and 19% (12-30) of patients were alive, respectively (hazard ratio [HR] for death, 0.64; 95% CI, 0.46-0.88). After adjusting for clinical and molecular baseline characteristics, treatment with HMA-VEN remained significantly associated with both prolonged survival (HR, 0.48; 95% CI, 0.29-0.77) and time to next treatment (HR, 0.63; 95% CI, 0.47-0.85). Patients who achieved recovery of peripheral blood counts had a favorable prognosis (HR for death, 0.52; 95% CI, 0.33-0.84). DISCUSSION: These data align with findings from the pivotal VIALE-A trial and support the use of HMA-VEN in patients unfit for intensive therapy.

Phase II trial of hypomethylating agent combined with nivolumab for acute myeloid leukaemia relapse after allogeneic haematopoietic cell transplantation-Immune signature correlates with response.

Acute myeloid leukaemia (AML) relapse after allogeneic haematopoietic cell transplantation (allo-HCT) is often driven by immune-related mechanisms and associated with poor prognosis. Immune checkpoint inhibitors combined with hypomethylating agents (HMA) may restore or enhance the graft-versus-leukaemia effect. Still, data about using this combination regimen after allo-HCT are limited. We conducted a prospective, phase II, open-label, single-arm study in which we treated patients with haematological AML relapse after allo-HCT with HMA plus the anti-PD-1 antibody nivolumab. The response was correlated with DNA-, RNA- and protein-based single-cell technology assessments to identify biomarkers associated with therapeutic efficacy. Sixteen patients received a median number of 2 (range 1-7) nivolumab applications. The overall response rate (CR/PR) at day 42 was 25%, and another 25% of the patients achieved stable disease. The median overall survival was 15.6 months. High-parametric cytometry documented a higher frequency of activated (ICOS+ , HLA-DR+ ), low senescence (KLRG1- , CD57- ) CD8+ effector T cells in responders. We confirmed these findings in a preclinical model. Single-cell transcriptomics revealed a pro-inflammatory rewiring of the expression profile of T and myeloid cells in responders. In summary, the study indicates that the post-allo-HCT HMA/nivolumab combination induces anti-AML immune responses in selected patients and could be considered as a bridging approach to a second allo-HCT. Trial-registration: EudraCT-No. 2017-002194-18.

The landscape of novel strategies for acute myeloid leukemia treatment: Therapeutic trends, challenges, and future directions.

Acute myeloid leukemia (AML) is a highly heterogeneous subtype of hematological malignancies with a wide spectrum of cytogenetic and molecular abnormalities, which makes it difficult to manage and cure. Along with the deeper understanding of the molecular mechanisms underlying AML pathogenesis, a large cohort of novel targeted therapeutic approaches has emerged, which considerably expands the medical options and changes the therapeutic landscape of AML. Despite that, resistant and refractory cases caused by genomic mutations or bypass signalling activation remain a great challenge. Therefore, discovery of novel treatment targets, optimization of combination strategies, and development of efficient therapeutics are urgently required. This review provides a detailed and comprehensive discussion on the advantages and limitations of targeted therapies as a single agent or in combination with others. Furthermore, the innovative therapeutic approaches including hyperthermia, monoclonal antibody-based therapy, and CAR-T cell therapy are also introduced, which may provide safe and viable options for the treatment of patients with AML.

Clearance of bone marrow mast cells after hypomethylating agent and venetoclax for systemic mastocytosis associated with myeloid neoplasia.

Systemic mastocytosis (SM) results from clonal proliferation of neoplastic mast cells that infiltrate bone marrow and other organs. A major subset of patients with SM has a clonally related myeloid neoplasm and the SM itself (SM-AMN). We evaluated the efficacy of hypomethylating agent and venetoclax (HMA-VEN) to target both the myeloid neoplasm and mast cell infiltrate in a patient with SM associated with acute myeloid leukemia arising from myelodysplastic syndrome and illustrate complete elimination of bone marrow mast cells and complete remission of MDS/AML. This case illustrates the potent activity of HMA-VEN both against the AMN as well as the associated SM.

Current Therapeutic Landscape in Lower Risk Myelodysplastic Syndromes.

OPINION STATEMENT: Lower risk myelodysplastic syndromes are typically characterized by an indolent disease course with a relatively low risk of transformation into acute myeloid leukemia. These patients are classically identified using the revised International Prognostic Scoring System and most likely its molecular version in the near future which may change the paradigm of treatment. The overall goals of care are symptomatic control to reduce transfusion requirements and improve quality of life. Symptomatic anemia is the most common indication to initiate disease-specific therapies after the optimization of supportive measures. Currently, erythropoiesis-stimulating agents remain the standard upfront therapy for anemia, and patients with del(5q) cytogenetic changes can benefit from lenalidomide monotherapy. Other therapeutic options after failure of upfront treatment include luspatercept, hypomethylating agents, and immunosuppressive therapies after taking into account of individualized disease features. Allogeneic hematopoietic stem cell transplant is the only potentially curative option and is usually reserved for medically fit patients with severe symptomatic cytopenias who failed all standard options and/or the disease is progressing toward higher risk categories. Fortunately, novel investigational therapies are rapidly emerging by targeting different biological processes contributing to MDS pathogenesis, and eligible patients should be managed in clinical trials if available.

Pneumonitis after immune checkpoint inhibitor therapies in patients with acute myeloid leukemia: A retrospective cohort study.

BACKGROUND: Immune checkpoint inhibitors (ICI), combined with hypomethylating agents, can be used to treat acute myeloid leukemia (AML), but this strategy results in a high rate of pneumonitis. The authors sought to determine risk factors for pneumonitis development and whether pneumonitis increased mortality. METHODS: The authors conducted a retrospective review of 258 AML patients who received ICI-containing regimens from 2016 to 2018. A multidisciplinary adjudication committee diagnosed pneumonia and pneumonitis by reviewing symptoms, imaging, microbiology, and response to therapies. To measure risk factors for pneumonitis and mortality, multivariate Cox proportional hazards models were constructed. Pneumonia, pneumonitis, and disease progression were modeled as a time-dependent variable and incorporated a standard risk set modifying variables into the models. RESULTS: Thirty patients developed pneumonitis (12%). Of these, 17 had partial or complete resolution, whereas 13 patients died from pneumonitis. Increasing age (hazard ratio [HR], 1.04 per year; 95% confidence interval [CI], 1.00-1.08), and baseline shortness of breath increased pneumonitis risk (HR, 2.51; 95% CI, 1.13-5.55). Female sex (HR, 0.33; 95% CI, 0.15-0.70) and increasing platelet count (HR, 0.52 per log-unit increase; 95% CI, 0.30-0.92) decreased pneumonitis risk. In adjusted models, ICI-related pneumonitis significantly increased mortality (HR, 2.84; 95% CI, 1.84-4.37). CONCLUSIONS: ICI-related pneumonitis occurs at a high rate in AML patients and increases mortality. LAY SUMMARY: Immune checkpoint inhibitors (ICIs) remove inhibitory signals that reduce T-cell function and allow T-cells to better attack cancer cells. In acute myeloid leukemia (AML), the effectiveness of ICIs is limited in part by inflammation of the lung, called pneumonitis. This study reviewed 258 patients with AML who received ICIs and identified 30 patients who developed pneumonitis, nearly half of whom died. Older age and baseline shortness of breath increased pneumonitis risk, whereas female sex and higher baseline platelet counts decreased pneumonitis risk. Pneumonitis increased mortality by nearly 3-fold. This work highlights the significant harm imposed by pneumonitis after ICI therapies.

Combination romidepsin and azacitidine therapy is well tolerated and clinically active in adults with high-risk acute myeloid leukaemia ineligible for intensive chemotherapy.

Azacitidine (AZA) is important in the management of patients with acute myeloid leukaemia (AML) who are ineligible for intensive chemotherapy. Romidepsin (ROM) is a histone deacetylase inhibitor which synergises with AZA in vitro. The ROMAZA trial established the maximum tolerated dose (MTD) of combined ROM/AZA therapy in patients with AML, as ROM 12 mg/m2 on Days 8 and 15, with AZA 75 mg/m2 administered for 7/28 day cycle. Nine of the 38 (23·7%) patients treated at the MTD were classified as responders by Cycle 6 (best response: complete remission [CR]/incomplete CR n = 7, partial response n = 2). Correlative next-generation sequencing studies demonstrated important insights into therapy resistance.

Characterisation of infections in patients with acute myeloid leukaemia receiving venetoclax and a hypomethylating agent.

We investigated the incidence of invasive fungal infections (IFIs) and other infectious complications in patients receiving venetoclax and hypomethylating agent therapy for acute myeloid leukaemia (AML). This retrospective, multicentre cohort study included adult patients with AML who received at least one cycle of venetoclax and either azacitidine or decitabine between January 2016 and August 2020. The primary outcome was the incidence of probable or confirmed IFI. Secondary outcomes included antifungal prophylaxis prescribing patterns, incidence of bacterial infections, and incidence of neutropenic fever hospital admissions. Among 235 patients, the incidence of probable or confirmed IFI was 5.1%. IFI incidence did not differ significantly according to age, antifungal prophylaxis use, or disease status. In the subgroup of patients with probable or confirmed IFIs, six (50%) were receiving antifungal prophylaxis at the time of infection. The overall incidence of developing at least one bacterial infection was 33.6% and 127 (54%) patients had at least one hospital admission for febrile neutropenia. This study demonstrated an overall low risk of developing probable or confirmed IFI as well as a notable percentage of documented bacterial infections and hospital admissions due to neutropenic fever.

Outcomes in patients with newly diagnosed TP53-mutated acute myeloid leukemia with or without venetoclax-based therapy.

BACKGROUND: Venetoclax (VEN) in combination with a hypomethylating agent (HMA) has become the standard of care for patients aged >75 years and for those not eligible for intensive chemotherapy who have newly diagnosed acute myeloid leukemia (AML). The benefit of VEN-based therapy in patients who have newly diagnosed AML with mutations in the TP53 gene (TP53mut ) over standard therapy is undefined. METHODS: In this single-institutional, retrospective analysis, the authors assessed the clinical outcomes of 238 patients with newly diagnosed TP53mut AML and compared the clinical characteristics, response to different therapies, and outcomes of those who received VEN-based (n = 58) and non-VEN-based (n = 180) regimens. RESULTS: Patients who received VEN-based regimens were older (aged >65 years: 81% vs 65%; P = .02) and had higher response rates (complete remission, 43% vs 32%; P = .06) than those who received non-VEN-based regimens. Compared with patients who received non-VEN-based regimens, no difference in overall survival (median, 6.6 vs 5.7 months; P = .4) or relapse-free survival (median, 4.7 vs 3.5 months; P = .43) was observed in those who received VEN-based regimens, regardless of age or intensity of treatment. CONCLUSIONS: The addition of VEN to standard treatment regimens did not improve outcomes in younger or older patients who had TP53mut AML. These data highlight the need for novel therapies beyond VEN to improve the outcome of patients with TP53mut AML.

Phase II study of azacitidine with pembrolizumab in patients with intermediate-1 or higher-risk myelodysplastic syndrome.

Programmed cell death protein 1 (PD-1) and PD-ligand 1 (PD-L1) expression is upregulated in cluster of differentiation 34 (CD34)+ bone marrow cells from patients with myelodysplastic syndromes (MDS). Hypomethylating agent (HMA) treatment results in further increased expression of these immune checkpoints. We hypothesised that combining an anti-PD-1 antibody with HMAs may have efficacy in patients with MDS. To test this concept, we designed a phase II trial of the combination of azacitidine and pembrolizumab with two cohorts. In the 17 previously untreated patients, the overall response rate (ORR) was 76%, with a complete response (CR) rate of 18% and median overall survival (mOS) not reached after a median follow-up of 12·8 months. For the HMA-failure cohort (n = 20), the ORR was 25% and CR rate was 5%; with a median follow-up of 6·0 months, the mOS was 5·8 months. The most observed toxicities were pneumonia (32%), arthralgias (24%) and constipation (24%). Immune-related adverse events requiring corticosteroids were required in 43%. Overall, this phase II trial suggests that azacitidine and pembrolizumab is safe with manageable toxicities in patients with higher-risk MDS. This combined therapy may have anti-tumour activity in a subset of patients and merits further studies in the front-line setting.

The Prognostic Ability of RAS Pathway-Related Gene Mutations in Patients with Myeloid Neoplasms Treated with Hypomethylating Agents.

INTRODUCTION: This study aimed to identify genetic predictors of treatment response and survival in patients with myeloid neoplasms treated with hypomethylating agents (HMAs). METHODS: We performed next-generation sequencing on bone marrow aspiration samples of 59 patients diagnosed with acute myeloid leukemia (AML), myelodysplastic syndrome with excess blasts-2, or chronic myelomonocytic leukemia and treated with decitabine or azacitidine as a frontline therapy. RESULTS: A single gene with the most common mutations was TP53 (14 of 59 patients), and mutations in RAS pathway-related genes including KRAS, NRAS, FLT3, PTPN11, CBL, and KIT were found in 28.8% of patients. The overall response rate to HMAs was 33.9%. Predictive factors for a poor response were an age >75 years (p = 0.007), 3 or more gene mutations (p = 0.004), mutations in RAS pathway-related genes (p = 0.033), and a mutated NRAS gene (p = 0.042). An age >75 years (hazard ratio 2.946), diagnosis of AML (hazard ratio 2.915), and mutations in NRAS (hazard ratio 4.440) were identified as poor prognostic factors for survival. CONCLUSION: In conclusion, mutations in RAS pathway-related genes were predictors of a poor response to HMAs. Particularly, mutated NRAS was associated with inferior survival rates.

New Treatment Options for Older Patients with Acute Myeloid Leukemia.

OPINION STATEMENT: The treatment of acute myeloid leukemia (AML) has evolved considerably over the past several years. Advances in the field have historically benefited younger patients; however, a growing understanding of the molecular basis of leukemogenesis has brought multiple targeted agents to the clinic for patients of all ages. These therapies have expanded the therapeutic landscape for elderly patients from more than best supportive care and low-intensity monotherapy. In general, we currently utilize a backbone regimen of a hypomethylating agent (HMA) or low-intensity chemotherapy with the BCL-2 inhibitor venetoclax for the majority of elderly patients with newly diagnosed AML. For patients with targetable mutations, we employ a doublet/triplet strategy of HMA + a targeted inhibitor +/- venetoclax, often in the context of a clinical trial. CPX-351 is reserved for patients with secondary or therapy-related AML. In this review, we will outline our approach to the treatment of elderly patients with AML, with particular emphasis on recently approved agents and emerging novel therapies.

Venetoclax-based combinations for the treatment of newly diagnosed acute myeloid leukemia.

Elderly and/or unfit patients with acute myeloid leukemia have historically been challenging to manage as they were ineligible for what was considered standard of care treatment with induction chemotherapy. The emergence of venetoclax with hypomethylating agents or low-dose cytarabine has substantially improved outcomes in the frontline setting with manageable toxicity. However, this regimen can be challenging to deliver given its differences from standard intensive chemotherapy. In this review, we summarize the landmark trials that established venetoclax-based combinations as a new standard of care for patients with acute myeloid leukemia not suitable for intense chemotherapy, provide practical clinical pearls for managing patients on these therapies, and offer a brief overview of modifications to these regimens under development to improve their efficacy and/or applicability.

Lay abstract Older and/or unfit patients with acute myeloid leukemia (AML) have historically had bad outcomes with standard therapies and an overall dismal prognosis. The advent of venetoclax (VEN)-based regimens has led to significantly improved responses for patients with untreated AML with an acceptable safety profile. However, delivering these therapies are associated with their own unique challenges. In this review, we summarize the key trials that demonstrated the success of VEN-based combinations in this particular AML population, provide practical considerations for managing patients on these therapies, and discuss ongoing studies to further improve VEN-based therapy.

The myeloid sarcoma treated by Venetoclax with hypomethylating agent followed by stem cell transplantation: rare case report.

BACKGROUND: Myeloid sarcoma (MS) is a very rare condition, develops both in patients with other hematological neoplasms, and as isolated tumor. MS of the gynecologic tract is extremely rare. An available literature data about diagnosis and management of MS is summarized in the article. The role of chemotherapy, radiation therapy, surgery and bone marrow transplantation in the treatment is discussed. Polychemotherapy and allogeneic bone marrow transplantation were suggested to be the optimal treatment strategy of MS of the gynecological tract. The use of new targeted agents results in promising clinical data. CASE PRESENTATION: We are presenting a rare clinical case of a MS of the uterine cervix with concomitant bone marrow involvement and describe all the peculiarities of the clinical course, diagnosis, and treatment. The patient received chemotherapy followed by allogeneic bone marrow transplantation. The pre-transplant therapy allowed us to perform allogeneic bone marrow transplantation with the deepest response possible: complete PET-negative and MRD-negative remission of the disease. CONCLUSIONS: MS remains a subject of discussion regarding its diagnostic and therapeutic aspects. The use of novel targeting agents can be perspective option for patient with extramedullary disease.

Novel agents for myelodysplastic syndromes.

REVIEW OBJECTIVE: There have been several advances in the field of myelodysplastic syndromes over the past year, yielding two new US Food and Drug Administration drug approvals. The pharmacology, pharmacokinetics, clinical trials, therapeutic use, adverse effects, clinical use controversies, product description, and upcoming trials for myelodysplastic syndromes novel agents luspatercept-aamt and decitabine/cedazuridine are reviewed. DATA SOURCES: This review article utilized primary information obtained from both the published studies involved in the approval of luspatercept-aamt and decitabine/cedazuridine and package inserts for the respective medications. This review article utilized secondary information obtained from National Comprehensive Cancer Network guidelines using filters and keywords to sustain information relevancy as well as key studies using the keywords, "luspatercept-aamt, myelodysplastic syndromes, decitabine, cedazuridine, hypomethylating agent, ASTX727" from scholarly journal database PubMed. DATA SUMMARY: Myelodysplastic syndromes consist of myeloid clonal hemopathies with a diverse range of presentation. Until recently, there have been relatively few new therapies in the myelodysplastic syndromes treatment landscape. On April 3, 2020 the US Food and Drug Administration approved Reblozyl®(luspatercept-aamt), then on July 7, 2020, the US Food and Drug Administration approved INQOVI® (decitabine and cedazuridine). Luspatercept-aamt acts as a erythroid maturation agent through differentiation of late-stage erythroid precursors. The safety and efficacy of luspatercept-aamt was demonstrated in the MEDALIST trial, a phase III trial in patients with very low-intermediate risk refractory myelodysplastic syndromes and ring sideroblasts. Luspatercept-aamt met both primary and secondary endpoints of transfusion independence of 8 weeks or longer and transfusion independence of 12 weeks or longer, respectively. Decitabine/cedazuridine has a unique mechanism of action in which decitabine acts as a nucleoside metabolic inhibitor promoting DNA hypomethylation and cedazuridine then prevents degradation of decitabine. The safety and efficacy of decitabine/cedazuridine was shown in the ASCERTAIN study, a phase III trial in patients with intermediate or high risk myelodysplastic syndromes or chronic myelomonocytic leukemia. The primary outcome evaluated was 5-day cumulative area under the curve between decitabine/cedazuridine and IV decitabine as well as additional outcomes including safety. Decitabine/cedazuridine met primary outcome and had a similar safety profile to IV decitabine. CONCLUSION: The novel myelodysplastic syndromes agents luspatercept-aamt and decitabine/cedazuridine provide a clinical benefit in the studied populations.

Autoimmune hemolytic anemia in a patient with myelodysplastic syndrome: Responding to 5-azacitidine therapy.

INTRODUCTION: Autoimmune disorders, including autoimmune cytopenias, are more common in patients with myelodysplastic syndrome (MDS) and may share with MDS the same steps of pathogenesis. Some patients with MDS have antibodies against red cells. CASE REPORT: We describe herein a 79-year-old patient who presented with fatigue, jaundice and pancytopenia. She was diagnosed with warm-antibody autoimmune hemolytic anemia (AIHA) and synchronous MDS.Management and outcome: In our patient, AIHA responded to the hypomethylating agent 5-azacitidine used for the treatment of MDS. Six months later, the patient remains in clinico-laboratory remission for both MDS and AIHA. DISCUSSION/CONCLUSIONS: Our case indirectly suggests that 5-azacitidine led to a decrease in autoantibody production by the auto-reactive B-cell clone in MDS leading in turn to a diminished rate of autoimmune hemolysis. If our observation is accurate, we believe that similar reports will populate the scientific literature in the future years.

Deciphering the Therapeutic Resistance in Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is a clonal hematopoietic disorder characterized by abnormal proliferation, lack of cellular differentiation, and infiltration of bone marrow, peripheral blood, or other organs. Induction failure and in general resistance to chemotherapeutic agents represent a hindrance for improving survival outcomes in AML. Here, we review the latest insights in AML biology concerning refractoriness to therapies with a specific focus on cytarabine and daunorubicin which still represent milestones agents for inducing therapeutic response and disease eradication. However, failure to achieve complete remission in AML is still high especially in elderly patients (40-60% in patients >65 years old). Several lines of basic and clinical research have been employed to improve the achievement of complete remission. These lines of research include molecular targeted therapy and more recently immunotherapy. In terms of molecular targeted therapies, specific attention is given to DNMT3A and TP53 mutant AML by reviewing the mechanisms underlying epigenetic therapies' (e.g., hypomethylating agents) resistance and providing critical points and hints for possible future therapies overcoming AML refractoriness.

Epigenetics in myelodysplastic syndromes.

Epigenetic regulators are the largest group of genes mutated in MDS patients. Most mutated genes belong to one of three groups of genes with normal functions in DNA methylation, in H3K27 methylation/acetylation or in H3K4 methylation. Mutations in the majority of epigenetic regulators disrupt their normal function and induce a loss-of-function phenotype. The transcriptional consequences are often failure to repress differentiation programs and upregulation of self-renewal pathways. However, the mechanisms how different epigenetic regulators result in similar transcriptional consequences are not well understood. Hypomethylating agents are active in higher risk MDS patients, but their efficacy does not correlate with mutations in epigenetic regulators and the median duration of hematologic response is limited to 10-13 months. Inhibitors of histone deacetylases (HDAC) yielded disappointing results so far, questioning this approach in MDS patients. We review the clinical relevance of epigenetic mutations in MDS, discuss their functional consequences and highlight the role of epigenetic therapies in this difficult to treat disease.