Comparative analysis between azacitidine and decitabine for the treatment of myelodysplastic syndromes

Beyond the horizon: emerging therapeutic approaches in myelodysplastic neoplasms

Management of myelodysplastic neoplasms (MDS) requires a personalized approach, with a focus on improving quality of life and extending lifespan. The International Prognostic Scoring System-Revised and the molecular International Prognostic Scoring System are key tools for risk stratification and management of MDS. They provide a framework for predicting survival and the risk of transformation to acute myeloid leukemia. However, a major challenge in MDS management remains the limited therapeutic options available, especially after the failure of first-line therapies. In lower-risk MDS, the failure of erythropoietin-stimulating agents often leaves few alternatives, although in higher-risk MDS, the prognosis after hypomethylating agent failure is dismal. This highlights the urgent need for novel, more personalized therapeutic approaches. In this review, we discuss emerging novel therapeutic approaches in the treatment of MDS. Several new therapeutic targets are currently being evaluated, offering hope for improved management of MDS in the future.

Efficacy of epigenetic agents for older patients with acute myeloid leukemia and myelodysplastic syndrome in randomized controlled trials: a systematic review and network meta-analysis

Myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) are hematologic malignancies that mostly affect the elderly and have poor prognoses. Mutations in epigenetic regulatory genes cause AML/MDS through changes in DNA methylation and histone modifications. Some epigenetic agents are used in patients with AML and MDS. However, most studies have focused on azacitidine (AZA) or decitabine (DEC), and few studies have been conducted on combination therapies or other epigenetic therapies. This network meta-analysis (NMA) aimed to compare the efficacy of epigenetic agents overall in patients with AML and MDS. A systematic review and NMA of all available II-III phase randomized controlled trials (RCTs) comparing epigenetic agents were performed. The Embase and PubMed databases were searched for relevant studies. The Bayesian model was used in the NMA, and the surface under the cumulative ranking curve (SUCRA) was used to rank comparisons. The primary endpoint was overall survival (OS), and the secondary endpoints were complete response (CR) and partial response (PR). OS was extended by AZA + venetoclax (SUCRA 0.94) in patients with AML and MDS. DEC (SUCRA 0.78) relatively improved CR and PR. In this study, AZA-related treatment was relatively effective in improving the OS of patients with AML and MDS, and DEC-related treatment showed a relatively high effect on CR and PR. The protocol for this systematic review was registered with the International Prospective Register of Systematic Reviews (CRD42022303601).

Epigenetic inhibitors for cancer treatment

Epigenetics is a heritable and reversible modification that occurs independent of the alteration of primary DNA sequence but remarkably affects genetic expression. Aberrant epigenetic regulators are frequently observed in cancer progression not only influencing the behavior of tumor cells but also the tumor-associated microenvironment (TME). Increasing evidence has shown their great potential as biomarkers to predict clinical outcomes and chemoresistance. Hence, targeting the deregulated epigenetic regulators would be a compelling strategy for cancer treatment. So far, current epigenetic drugs have shown promising efficacy in both preclinical trials and clinical treatment of cancer, which encourages research discoveries on the development of novel epigenetic inhibitors either from natural compounds or artificial synthesis. However, only a few have been approved by the FDA, and more effort needs to be put into the related research. This chapter will update the applications and latest progress of epigenetic inhibitors in cancer treatment and provide prospects for the future development of epigenetic drugs.

Incidence and predisposing factors of infection in patients treated with hypomethylating agents

OBJECTIVE

Hypomethylating agents may have adverse effects such as cytopenias, cytopenia associated infections and fatality due to infections despite their favorable effects in the treatment of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). The infection prophylaxis approach is based on expert opinions and real-life experiences. Hence, we aimed to reveal the frequence of infections, predisposing factors of infection and to analyse infection attributable mortality in patients with high-risk MDS, CMML and AML who received hypomethylating agents in our center where routine infection prophylaxis is not applied.

MATERIAL-METHOD

43 adult patients with AML or high-risk MDS or CMML who received HMA ≥ 2 consecutive cycles from January 2014 to December 2020 were enrolled in the study.

RESULTS

43 patients and 173 treatment cycles were analyzed. The median age was 72 years and 61.3 % of patients were males. The distribution of the patients' diagnoses was; AML in 15 patients (34.9 %), high risk MDS in 20 patients (46.5 %), AML with myelodysplasia-related changes in 5 patients (11.6 %) and CMML in 3 patients (7 %). 38 infection events (21.9 %) occurred in 173 treatment cycles. 86.9 % (33 cycles) and 2.6 % (1 cycle) of infected cycles were bacterial and viral infections, respectively and 10.5 % (4 cycles) were bacterial and fungal concurrently. The most common origin of the infection was respiratory system. Hemoglobin count was lower and CRP level was higher at the beginning of the infected cycles significantly (p values were 0.002 and 0.012, respectively). Requirement of red blood cell and platelet transfusions were found to be significantly increased in the infected cycles (p values were 0.000 and 0.001, respectively). While > 4 cycles of treatment and increased platelet count were found to be protective against infection, > 6 points of Charlson Comorbidity Index (CCI) were found to increase the risk of infection. The median survival was 7.8 months in non-infected cycles while 6.83 months in infected cycles. This difference was not statistically significant (p value was 0.077).

DISCUSSION

The prevention and management of infections and infection-related deaths in patients treated with HMAs is crucial. Therefore, patients with a lower platelet count or a CCI score of > 6 may be candidates for infection prophylaxis when exposed to HMAs.

Global Proteomics Analysis of Bone Marrow: Establishing Talin-1 and Centrosomal Protein of 55 kDa as Potential Molecular Signatures for Myelodysplastic Syndromes

Myelodysplastic syndrome (MDS) is a hematological disorder characterized by abnormal stem cell differentiation and a high risk of acute myeloid leukemia transformation. Treatment options for MDS are still limited, making the identification of molecular signatures for MDS progression a vital task. Thus, we evaluated the proteome of bone marrow plasma from patients (n = 28) diagnosed with MDS with ring sideroblasts (MDS-RS) and MDS with blasts in the bone marrow (MDS-EB) using label-free mass spectrometry. This strategy allowed the identification of 1,194 proteins in the bone marrow plasma samples. Polyubiquitin-C (UBC), moesin (MSN), and Talin-1 (TLN1) showed the highest abundances in MDS-EB, and centrosomal protein of 55 kDa (CEP55) showed the highest relative abundance in the bone marrow plasma of MDS-RS patients. In a follow-up, in the second phase of the study, expressions of UBC, MSN, TLN1, and CEP55 genes were evaluated in bone marrow mononuclear cells from 45 patients by using qPCR. This second cohort included only seven patients from the first study. CEP55, MSN, and UBC expressions were similar in mononuclear cells from MDS-RS and MDS-EB individuals. However, TLN1 gene expression was greater in mononuclear cells from MDS-RS (p = 0.049) as compared to MDS-EB patients. Irrespective of the MDS subtype, CEP55 expression was higher (p = 0.045) in MDS patients with abnormal karyotypes, while MSN, UBC, and TALIN1 transcripts were similar in MDS with normal vs. abnormal karyotypes. In conclusion, proteomic and gene expression approaches brought evidence of altered TLN1 and CEP55 expressions in cellular and non-cellular bone marrow compartments of patients with low-risk (MDS-RS) and high-risk (MDS-EB) MDSs and with normal vs. abnormal karyotypes. As MDS is characterized by disrupted apoptosis and chromosomal alterations, leading to mitotic slippage, TLN1 and CEP55 represent potential markers for MDS prognosis and/or targeted therapy.

Tumor suppressor CEBPA interacts with and inhibits DNMT3A activity

DNA methyltransferases (DNMTs) catalyze DNA methylation, and their functions in mammalian embryonic development and diseases including cancer have been extensively studied. However, regulation of DNMTs remains under study. Here, we show that CCAAT/enhancer binding protein α (CEBPA) interacts with the long splice isoform DNMT3A, but not the short isoform DNMT3A2. CEBPA, by interacting with DNMT3A N-terminus, blocks DNMT3A from accessing DNA substrate and thereby inhibits its activity. Recurrent tumor-associated CEBPA mutations, such as preleukemic CEBPA^N321D mutation, which is particularly potent in causing AML with high mortality, disrupt DNMT3A association and cause aberrant DNA methylation, notably hypermethylation of PRC2 target genes. Consequently, leukemia cells with the CEBPA^N321D mutation are hypersensitive to hypomethylation agents. Our results provide insights into the functional difference between DNMT3A isoforms and the regulation of de novo DNA methylation at specific loci in the genome. Our study also suggests a therapeutic strategy for the treatment of CEBPA-mutated leukemia with DNA-hypomethylating agents.

Differential Histone Posttranslational Modifications Induced by DNA Hypomethylating Agents

Introduction

The prototype DNA hypomethylating agents 5-azacytidine (5AC) and decitabine (DAC) are currently FDA-approved for treatment of blood and bone marrow disorders like myelodysplastic syndrome. 5AC and DAC are considered similar drugs and were shown to induce histone modifications that modulate gene expression. The aim of this study is to compare the effect of both drugs on histone acetylation and methylation at multiple histone amino acids residues.

Methods

Mass spectrometry was used to compare the effect of both drugs on 95 different histone posttranslational modifications (PTMs) in leukemia cells. ChIP-Seq analysis was used to compare the impact of both drugs on the genome-wide acetylation of the H3K9 mark using primary leukemia cells from six de-identified AML patients.

Results

Both DAC and 5AC induced histone PTMs in different histone isoforms like H1.4, H2A, H3, H3.1, and H4. Changes in both histone methylation and acetylation were observed with both drugs; however, there were distinct differences in the histone modifications induced by the two drugs. Since both drugs were shown to increase the activity of the HDAC SIRT6 previously, we tested the effect of 5AC on the acetylation of H3K9, the physiological substrate SIRT6, using ChIP-Seq analysis and compared it to the previously published DAC-induced changes. Significant H3K9 acetylation changes (P< .05) were detected at 925 genes after 5AC treatment vs only 182 genes after DAC treatment. Nevertheless, the gene set modified by 5AC was different from that modified by DAC with only ten similar genes modulated by both drugs.

Conclusion

Despite similarity in chemical structure and DNA hypomethylating activity, 5AC and DAC induced widely different histone PTMs and considering them interchangeable should be carefully evaluated. The mechanism of these histone PTM changes is not clear and may involve modulation of the activity or the expression of the enzymes inducing histone PTMs.

Comparison Between Decitabine and Azacitidine for Patients With Acute Myeloid Leukemia and Higher-Risk Myelodysplastic Syndrome: A Systematic Review and Network Meta-Analysis

Background: The hypomethylating agents (HMAs) azacitidine (AZA) and decitabine (DAC) have been widely used in patients with acute myeloid leukemia (AML) and higher-risk myelodysplastic syndrome (HR-MDS). However, few direct clinical trials have been carried out to compare the efficacy and adverse events (AEs) between these two agents. The clinical choice between them is controversial. A systematic review and network meta-analysis (NMA) was performed to compare the efficacy, safety, and survival of DAC and AZA in AML and HR-MDS patients.

Methods: We systematically searched MEDLINE, Embase, Web of Science, and Cochrane Library through March 15, 2021. Randomized controlled trials (RCTs) on AML or HR-MDS patients comparing the efficacy and safety between DAC and AZA or comparing one of HMAs to conventional care regimens (CCR) were selected.

Results: Eight RCTs (n = 2,184) were identified in the NMA. Four trials compared AZA to CCR, and four compared DAC to CCR. Direct comparisons indicated that, compared to CCR, both AZA and DAC were associated with higher overall response (OR) rate (AZA vs. CCR: relative risk (RR) = 1.48, 95% CI 1.05–2.1; DAC vs. CCR: RR = 2.14, 95% CI 1.21–3.79) and longer overall survival (OS) (AZA vs. CCR: HR = 0.64, 95% CI 0.50–0.82; DAC vs. CCR: HR = 0.84, 95% CI 0.72–0.98), and AZA showed higher rate of complete remission with incomplete blood count recovery (CRi) (HR = 2.52, 95% CI 1.27–5). For the indirect method, DAC showed a higher complete remission (CR) rate than AZA in patients with both AML (RR = 2.28, 95% CI 1.12–4.65) and MDS (RR = 7.57, 95% CI 1.26–45.54). Additionally, DAC significantly increased the risk of 3/4 grade anemia (RR = 1.61, 95% CI: 1.03–2.51), febrile neutropenia (RR = 4.03, 95% CI: 1.41–11.52), and leukopenia (RR = 3.43, 95% CI 1.64–7.16) compared with AZA. No statistical significance was found for the other studied outcomes.

Conclusion: Compared to CCR, both AZA and DAC can promote outcomes in patients with AML and HR-MDS. DAC showed higher efficacy especially CR rate than AZA (low-certainty evidence), while AZA experienced lower frequent grade 3/4 cytopenia than patients receiving DAC treatment.

Hypomethylating agents in the treatment of chronic myelomonocytic leukemia: a meta-analysis and systematic review

OBJECTIVES

The present meta-analysis was performed to evaluate the efficacy, toxicities of both hypomethylating agents (decitabine and azaciticine) in the treatment of CMML patients.

METHODS

All available cohort studies of patients with CMML treated with decitabine and azacitidine were identified. The primary endpoints of this meta-analysis were response to hypomethylating agents. Pooled estimates of treatment response and drug-related adverse events were calculated using fixed or random effect models.

RESULTS

Fourteen studies with 600 CMML patients (decitabine: n=196; azacitidine: n=404) were identified and included for meta-analysis. HMAs yielded a pooled ORR estimate of 43% (95% CI: 36%-50%) in patients with CMML. Patients received either azacitidine or decitabine exhibited comparable incidence of ORR (43% vs. 45%, P=0.810), while significantly higher incidence of mCR was observed in patients treated with decitabine (23% vs. 10%, P=0.000). Decitabine treatment was also associated with higher incidence of transfusion independence (42% vs. 20%, P=0.044). Both HMAs led to objective hematologic or non-hematologic AEs (27%-43%), while dosage modification/delay were more frequent in patients treated with azacitidine (81% vs. 67%, P=0.021).

CONCLUSION

This current study may provide preliminary data in evaluating the efficacy and safety of HMAs in patients with CMML. Decitabine and azacitidine are comparable effective and safe in treating CMML. However, it is necessary to point out that any comparison of decitabine and azacitidine with respect to clinical outcomes can only be done in the context of a randomized controlled trial.

Recent Clinical Update of Acute Myeloid Leukemia: Focus on Epigenetic Therapies

Acute myeloid leukemia (AML) is a complicated disease characterized by genetic heterogeneity and simultaneous alterations in multiple genes. For decades, its only curative method has been intensive induction chemotherapy with or without allogeneic hematopoietic stem cell transplantation, and this approach cannot be applied to elderly patients, who make up more than 50% of AML patients. Recent advances in genomics facilitated the elucidation of various mutations related to AML, and the most frequent mutations were discovered in epigenetic regulators. Alterations to epigenetic modifications that are essential for normal cell biology, including DNA methylation and histone acetylation, have been identified. As epigenetic dysregulation is an important carcinogenic mechanism and some epigenetic changes are reversible, these epigenetic alterations have become targets for novel drug development against AML. This review summarizes the recent advances in epigenetic therapies for AML and discusses future research directions.

Impacts of Epigenetic Processes on the Health and Productivity of Livestock

The dynamic changes in the epigenome resulting from the intricate interactions of genetic and environmental factors play crucial roles in individual growth and development. Numerous studies in plants, rodents, and humans have provided evidence of the regulatory roles of epigenetic processes in health and disease. There is increasing pressure to increase livestock production in light of increasing food needs of an expanding human population and environment challenges, but there is limited related epigenetic data on livestock to complement genomic information and support advances in improvement breeding and health management. This review examines the recent discoveries on epigenetic processes due to DNA methylation, histone modification, and chromatin remodeling and their impacts on health and production traits in farm animals, including bovine, swine, sheep, goat, and poultry species. Most of the reports focused on epigenome profiling at the genome-wide or specific genic regions in response to developmental processes, environmental stressors, nutrition, and disease pathogens. The bulk of available data mainly characterized the epigenetic markers in tissues/organs or in relation to traits and detection of epigenetic regulatory mechanisms underlying livestock phenotype diversity. However, available data is inadequate to support gainful exploitation of epigenetic processes for improved animal health and productivity management. Increased research effort, which is vital to elucidate how epigenetic mechanisms affect the health and productivity of livestock, is currently limited due to several factors including lack of adequate analytical tools. In this review, we (1) summarize available evidence of the impacts of epigenetic processes on livestock production and health traits, (2) discuss the application of epigenetics data in livestock production, and (3) present gaps in livestock epigenetics research. Knowledge of the epigenetic factors influencing livestock health and productivity is vital for the management and improvement of livestock productivity.

Evaluation of Reduced-Dose Decitabine and Azacitidine for Treating Myelodysplastic Syndromes: A Retrospective Study

Background

Hypomethylating agents (HMA) are considered the first-line therapy for high-risk myelodysplastic syndromes (MDS). However, as the efficacy and safety of rational dosing regimens are lacking, we evaluated the effectiveness and safety of reduced-dose azacitidine (AZA) vs. decitabine (DAC) in adult MDS patients.

Material/Methods

This retrospective study was conducted at the Institute of Hematology & Blood Diseases Hospital, for hospitalized MDS patients diagnosed (WHO 2008 classification criteria) from May 2006 to February 2020. These AZA- and DCA-naive patients treated with AZA 100 mg/(m²·day) for 5 days to 7 days or DAC 20 mg/(m²·day) for 3 days to 4 days, or 20 mg/(m²·day) 1 day/week for 3 weeks/month were assessed for treatment responses and adverse events.

Results

Of the 158 enrolled MDS patients, 120 and 38 patients were administered reduced-dose DAC and AZA, respectively. All the patients received a median of 2 treatment cycles. The overall response rates (ORR) were 50.0% and 73.3% in the AZA and DAC groups, respectively (P=0.007). The percentage of platelet transfusion dependence in the AZA group was lower than the DAC group (P=0.026). The multivariate analysis demonstrated that the DAC treatment was a significant factor for improved responses (OR 2.928; 95% CI 1.267–6.896; P=0.012), and the absolute neutrophil count (ANC) was a predictor of the ORR (OR 0.725; 95% CI 0.558–0.898; P=0.008). Neutropenia (P=0.016) and infection (P=0.032) incidences were higher in the DAC group.

Conclusions

The reduced-dose DAC group demonstrated a better response than the AZA group in MDS patients with different prognostic risks. The patients’ pre-treatment ANC was a significant factor associated with the ORR.

Asia-inclusive global development of pevonedistat: Clinical pharmacology and translational research enabling a phase 3 multiregional clinical trial

Abstract

The investigational NEDD8‐activating enzyme inhibitor pevonedistat is being evaluated in combination with azacitidine versus single‐agent azacitidine in patients with higher‐risk myelodysplastic syndrome (higher‐risk MDS), higher‐risk chronic myelomonocytic leukemia (higher‐risk CMML), or low‐blast acute myeloid leukemia (AML) in a Phase 3 trial PANTHER. To support Asia‐inclusive global development, we applied multiregional clinical trial (MRCT) principles of the International Conference on Harmonisation E17 guidelines by evaluating similarity in drug‐related and disease‐related intrinsic and extrinsic factors. A PubMed literature review (January 2000–November 2019) supported similarity in epidemiology of higher‐risk MDS, AML, and CMML in Western and East Asian populations. Furthermore, the treatment of MDS/AML was similar in both East Asian and Western regions, with the same dose of azacitidine being the standard of care. Median overall survival in MDS following azacitidine treatment was generally comparable across regions, and the types and frequencies of molecular alterations in AML and MDS were comparable. Dose‐escalation studies established the same maximum tolerated dose of pevonedistat in combination with azacitidine in Western and East Asian populations. Pevonedistat clearance was similar across races. Taken together, conservation of drug‐related and disease‐related intrinsic and extrinsic factors supported design of an Asia‐inclusive Phase 3 trial and a pooled East Asian region. A sample size of ~ 30 East Asian patients (of ~ 450 randomized) was estimated as needed to demonstrate consistency in efficacy relative to the global population. This analysis is presented as an exemplar to illustrate application of clinical pharmacology and translational science principles in designing Asia‐inclusive MRCTs.

Current and emerging strategies for management of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis with varying degrees of dysplasia and peripheral cytopenias. MDS are driven by structural chromosomal alterations and somatic mutations in neoplastic myeloid cells, which are supported by a tumorigenic and a proinflammatory marrow microenvironment. Current treatment strategies for lower-risk MDS focus on improving quality of life and cytopenias, while prolonging survival and delaying disease progression is the focus for higher-risk MDS. Several promising drugs are in the horizon, including the hypoxia-inducible factor stabilizer roxadustat, telomerase inhibitor imetelstat, oral hypomethylating agents (CC-486), TP53 modulators (APR-246 and ALRN-6924), and the anti-CD47 antibody magrolimab. Targeted therapies approved for acute myeloid leukemia treatment, such as isocitrate dehdyrogenase inhibitors and venetoclax, are also being studied for use in MDS. In this review, we provide a brief overview of pathogenesis and current treatment strategies in MDS followed by a discussion of newer agents that are under clinical investigation.

JAK-STAT inhibitor as a potential therapeutic opportunity in AML patients resistant to cytarabine and epigenetic therapy

The prognosis of AML is generally poor, with 5-year survival rate of 25%. There has been substantial progress in identification of new therapeutic targets, along with approval of at least three targeted therapies for AML in recent years. Nevertheless, treatment has largely remained unchanged over couple of decades, with ~40% patients not achieving remission. AML is a highly heterogenous disease and there is a need for a preclinical platform to understand the heterogeneity and tumor microenvironment that can guide therapy selection. In this study, we employed an ex vivo tumor explant model to study tumor microenvironment and to select a treatment course for AML patients. Our data reveal dysregulation of DNA methyltransferase (DNMT) and histone deacetylase (HDAC) in a subset of AML patients. Based on this observation, epigenetic modulators azacitidine and panobinostat alone and in combination, were evaluated as treatment regimens in cytarabine refractory tumors. More than 50% of the treated samples showed response to the combination therapy. In order to explore alternate treatment modalities for tumors refractory to these epigenetic modulators, TCGA data analysis was done which revealed increased expression and hypomethylation of IFNGR1/2, suggesting activation of JAK/STAT pathway in AML. This was further interrogated ex vivo, with p-STAT3 expression in patients' samples. Fedratinib, a JAK/STAT inhibitor was evaluated and 78% tumor efficacy response was achieved. Taken together, our data indicate that ex vivo platform derived from patient samples is capable in guiding optimal therapy selection for various classes of drugs including identification of novel targeted therapies.

Hypomethylating agent based combinations in higher risk myelodysplastic syndrome

For over a decade the hypomethylating agents (HMA) azacitidine and decitabine have been the mainstay of therapy for myelodysplastic syndrome (MDS). There is a critical need to improve frontline therapy, given that only up to half of high-risk MDS patients will respond to HMA therapy, and responses are short-lived. Currently, a key strategy has been to combine HMAs with other novel agents to improve patient outcomes. While synergy of agents is the goal of combination therapy, combinations often come at the cost of increased side effects that are often intolerable in this vulnerable population. The purpose of this review is to critically examine clinically relevant HMA combinations and discuss the future of MDS management.

Comparison between 5-day decitabine and 7-day azacitidine for lower-risk myelodysplastic syndromes with poor prognostic features: a retrospective multicentre cohort study

Numerous studies have analysed the clinical efficacies of hypomethylating agents (HMAs) in patients with myelodysplastic syndromes (MDS). However, reports that compare the two HMAs, decitabine and azacitidine, in patients with lower-risk (low and intermediate-1) MDS are limited. We compared 5-day decitabine and 7-day azacitidine regimens in terms of treatment responses, survival outcomes, and adverse events in patients with lower-risk MDS with poor prognostic features. The overall response rates (ORRs) were 67.2% and 44.0% in the patients treated with decitabine and azacitidine, respectively (P = 0.014). While the median progression-free survival (PFS) was significantly better in the patients treated with decitabine than in those treated with azacitidine (P = 0.019), no significant differences in event-free and overall survival rates were observed between the two groups. Multivariate analysis revealed that compared with azacitidine treatment, decitabine treatment is significantly associated with a higher ORR (P = 0.026) and longer PFS (P = 0.037). No significant differences were observed in the incidence of grade 3 or higher haematologic adverse events in response to the two HMAs. In conclusion, in lower-risk MDS, especially with poor prognostic features, ORR and PFS were significantly better with 5-day decitabine treatment than with 7-day azacitidine treatment, with comparable safety.

Effective demethylation of melanoma cells using terahertz radiation

Terahertz (THz) demethylation is a photomedical technique applied to dissociate methyl-DNA bonds and reduce global DNA methylation using resonant THz radiation. We evaluated the performance of THz demethylation and investigated the DNA damage caused by THz irradiation. The demethylation rate in M-293T DNA increased linearly with the irradiation power up to 48%. The degree of demethylation increased with exposure to THz radiation, saturating after 10 min. Although THz demethylation occurred globally, most of the demethylation occurred within the partial genes in the CpG islands. Subsequently, we performed THz demethylation of melanoma cells. The degree of methylation in the melanoma cell pellets decreased by approximately 10-15%, inducing ∼5-8 abasic sites per 10⁵ bp; this was considerably less than the damaged DNA irradiated by the high-power infrared laser beam used for generating THz pulses. These results provide initial data for THz demethylation and demonstrate the applicability of this technique in advanced cancer cell research. THz demethylation has the potential to develop into a therapeutic procedure for cancer, similar to that involving chemical demethylating agents.

The Impact of the Epigenetic Cancer Drug Azacitidine on Host Immunity: The Role of Myelosuppression, Iron Overload and tp53 Mutations in a Zebrafish Model

The unsatisfactory real-world efficacy of the hypomethylating agent azacitidine in treating myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) has prompted us to investigate the hematological adverse events and host variables that may compromise the use of this epigenetic drug. Using the zebrafish, we found that azacitidine destroyed their myeloid precursors and impaired myeloid function by inhibiting antigen processing, allogeneic response and phagocytic activity, resulting in increased susceptibility to infection even by the normal flora E. coli. In addition, iron overload, a MDS-associated condition following repeated transfusions, exacerbated bacterial infection especially by V. vulnificus with known iron dependence. Furthermore, we show that the tp53^M214K mutant zebrafish survived longer than the wild-type (WT) when challenged with bacteria following azacitidine treatment. This was attributed to the mutant’s hematopoietic cells rather than its general genetic background, since the WT animals reconstituted with the tp53^M214K mutant kidney marrow became more resistant to bacterial infection following treatment with azacitidine. The clinical relevance of our findings was indicated by a MDS case with severe azacitidine-induced bone marrow suppression and by the association of hyperferritinemia with bacteremia in azacitidine-treated patients, while tp53^M214K-mediated resistance to azacitidine-induced myelosuppression may explain the survival advantage of malignant MDS and AML clones over their normal counterparts under azacitidine treatment. Together, we propose that myelosuppression, iron overload and TP53 mutations may represent the host variables that compromise the azacitidine efficacy.

Hypomethylating agents in the treatment of acute myeloid leukemia: A guide to optimal use

The hypomethylating agents (HMAs), decitabine and azacitidine, are valuable treatment options in acute myeloid leukemia patients who are not eligible for intensive chemotherapy. Both agents are generally well tolerated, and complications most commonly relate to myelosuppression. Antibiotic / antifungal use, regular monitoring, and proactive patient education are important to minimize these events, and reduce the need for dose delay. Responses to HMAs are often not evident for up to 6 cycles, and there is currently no validated clinical marker for predicting response. Hence, treatment should be continued for at least 4-6 cycles to ensure that patients have sufficient opportunity to respond. Delivery of insufficient numbers of cycles is a key reason for HMA failure, and premature discontinuation must be avoided. Genetic factors offer potential for better predicting responders to HMAs in future, but require further study.

Treatment of MDS

The heterogeneous nature of myelodysplastic syndromes (MDS) demands a complex and personalized variety of therapeutic approaches. Among them, allogeneic hematopoietic stem cell transplantation remains the only potentially curative option and is accessible to only a small number of fit patients. For the majority of patients with MDS, treatment strategies are nonintensive and risk-adapted (by the revised version of the International Prognostic Scoring System), ranging from iron chelation and growth factors to lenalidomide and hypomethylating agents. These approaches are noncurative and aimed instead at improving cytopenias and quality of life and delaying disease progression. These limitations underpin the need for more translational research-based clinical trials in well-defined subgroups of patients with MDS. Indeed, much progress has been made over the past decade in understanding the complex molecular mechanisms underlying MDS. Unfortunately, this has not yet translated into approval of novel treatment options. There is a particularly urgent medical need in patients failing current first-line therapies, such as with erythropoiesis-stimulating or hypomethylating agents. Nevertheless, actual developments are expected to pave the way for exciting novel therapeutic opportunities. This review provides an overview of the current therapeutic landscape in MDS focusing on recent advances in clinical and translational research.

Infection control in patients with myelodysplastic syndromes who are candidates for active treatment: Expert panel consensus-based recommendations

The improvement in supportive care and the introduction of new therapeutic agents, including lenalidomide and hypomethylating agents, in myelodysplastic syndromes have improved patients' outcomes; however, at the same time, the frequency and epidemiology of infections have changed. Therefore, the great strides in the indications and use of new treatment strategies for myelodysplastic syndromes need a parallel progress in the best approach to prophylaxis and supportive therapy for infections. Based on the recognition that the above issues represent an unmet clinical need in myelodysplastic syndromes, an Italian expert panel performed a review of the literature and composed a framework of the best recommendations for optimal infection control in patient candidates to receive active treatment for myelodysplastic syndromes. In this consensus document we report the outcomes of that review and of the consensus meetings held during 2017. The issues tackled in the project dealt with: information to be collected from candidates for active treatment for myelodysplastic syndromes; how to monitor the risk of infection; antimicrobial prophylaxis; the role of iron chelation and antiviral/antibacterial vaccinations. For each of these issues, practice recommendations are provided.

An update on treatment of higher risk myelodysplastic syndromes

INTRODUCTION

Myelodysplastic syndromes (MDS) are clonal stem cell disorders mostly affecting the elderly. They are classified into lower and higher risk MDS according to prognostic scoring systems. In higher risk patients, treatments should aim to modify the disease course by avoiding progression to acute myeloid leukemia and, therefore, to improve survival. Areas covered: Stem cell transplantation remains the only curative treatment when feasible, but this concerns a small minority of patients. Treatment is principally based on hypomethylating agents (HMAs). Our understanding of MDS biology has led to the development of drugs targeting key cellular processes such as apoptosis or posttranslational protein changes, microenvironment-like immunotherapy, and gene mutations. Currently, new drugs are mainly being tested in combination with HMAs in several clinical trials. Expert commentary: Significant advances have been made in the field of MDS, especially in molecular typing, which are improving our ability to offer patients risk-adapted therapies. The current challenge in the management of higher risk MDS is to improve outcome by combining classical HMAs with novel drugs.

MicroRNA and Diabetic Complications: A Clinical Perspective

SIGNIFICANCE

The rising global prevalence of diabetes and its debilitating complications give rise to significant disability and premature mortality. Due to the silent nature of diabetes and its vascular complications, and limitations in current methods for detection, there is a need for novel biomarkers for early detection and prognosis. Recent Advances: Metabolic memory and epigenetic factors are important in the pathogenesis of diabetic complications and interact with genetic variants, metabolic factors, and clinical risk factors. Micro(mi)RNAs interact with epigenetic mechanisms and pleiotropically mediate the effects of hyperglycemia on the vasculature. Utilizing mature profiling techniques and platforms, an increasing number of miRNA signatures and interaction networks have been identified for diabetes and its related cardiorenal complications. As a result, these short, single-stranded molecules are emerging as potential diagnostic and predictive tools in human studies, and may function as disease biomarkers, as well as treatment targets.

CRITICAL ISSUES

However, there is complex interaction between the genome and epigenome. The regulation of miRNAs may differ across species and tissues. Most profiling studies to date lack validation, often requiring large, well-characterized cohorts and reliable normalization strategies. Furthermore, the incremental benefits of miRNAs as biomarkers, beyond prediction provided by traditional risk factors, are critical issues to consider, yet often neglected in published studies.

FUTURE DIRECTIONS

All in all, the future for miRNA-based diagnostics and therapeutics for diabetic complications appears promising. Improved understanding of the complex mechanisms underlying miRNA dysregulation, and more well-designed studies utilizing prospective samples would facilitate the translation to clinical use.

Incidence and risk of hematologic toxicities with hypomethylating agents in the treatment of myelodysplastic syndromes and acute myeloid leukopenia: A systematic review and meta-analysis

BACKGROUND

Hypomethylating agents (HMAs) are believed to have reliable efficacy in treating myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Meanwhile, the adverse events of HMAs have become an increasing concern. There is, however, no systematic meta-analysis available to evaluate overall hematologic toxicities for HMAs. In this meta-analysis, we aim to determine the risk of hematologic toxicities in patients treated with HMAs.

METHODS

Relevant studies were identified from PubMed, Embase, Cochrane Library, and the Clinical Trials. gov databases incepted to February 2018. All phase II and III trials meeting the inclusion criteria included adequate safety data. We calculated the relative risk (RR) of high-grade hematologic toxicities (HTEs) with corresponding 95% CI using Review Manager. The incidences of HTEs were also evaluated by R. Heterogeneity was calculated and reported mainly via I analyses.

RESULTS

A total of 2337 MDS or AML patients from 14 studies were identified in this meta-analysis. The overall incidences of high-grade hematologic toxicities in patients who received HMAs were: 27% of the patients with anemia, 45% with neutropenia, 38% with thrombocytopenia, and 25% with febrile neutropenia, respectively. There was a significantly increased RR of neutropenia and thrombocytopenia using HMAs, in comparison with conventional care regimens (CCR) based on the drug type (decitabine vs azacitidine).

CONCLUSIONS

We conclude that the use of HMAs are associated with an increased risk of neutropenia and thrombocytopenia in MDS or AML patients, and our results also demonstrate that HMAs exposure does not significantly increase the risk of high-grade anemia, leukopenia, or febrile neutropenia compared with CCR.

Clinical consequences of iron overload in patients with myelodysplastic syndromes: the case for iron chelation therapy

INTRODUCTION

Patients with myelodysplastic syndromes (MDS) are at increased risk of iron overload due to ineffective erythropoiesis and chronic transfusion therapy. The clinical consequences of iron overload include cardiac and/or hepatic failure, endocrinopathies, and infection risk. Areas covered: Iron chelation therapy (ICT) can help remove excess iron and ultimately reduce the clinical consequences of iron overload. The authors reviewed recent (last five years) English-language articles from PubMed on the topic of iron overload-related complications and the use of ICT (primarily deferasirox) to improve outcomes in patients with MDS. Expert commentary: While a benefit of ICT has been more firmly established in other transfusion-dependent conditions, such as thalassemia, its role in reducing iron overload in MDS remains controversial due to the lack of prospective controlled data demonstrating a survival benefit. Orally administered chelation agents (e.g. deferasirox) are now available, and observational and/or retrospective data support a survival benefit of using ICT in MDS. The placebo-controlled TELESTO trial (NCT00940602) is currently examining the use of deferasirox in MDS patients with iron overload, and is evaluating specifically whether use of ICT to alleviate iron overload can also reduce iron overload-related complications in MDS and improve survival.

HYPOMETHYLATING AGENTS IN TREATMENT OF MYELODYSPLASTIC SYNDROME

Thelkey to the successful treatment of myelodysplastic syndrome is the careful characterization and diagnosis of the disease, which includes clinical, cytogenetic, biological and molecular investigation of individual patients. Today therapeutic approaches to the treatment of such patients are differentiated and depend, first of all, on the subtype of the disease, age, general condition of the patients and the possibility of allogeneic hematopoietic cell transplantation. For young patients, the best option is transplantation, whereas in older patients, the standard of therapy is the use of hypomethylating agents (azacitidine, decitabine). These drugs promote hematologic improvement, elimination of transfusion dependence and prolongation of the duration of both general and leukemia free survival in elderly patients with concomitant pathology. Despite the fact that therapy with hypomethylating drugs is widely used and has good results, many respondents are losing their response within 1–2 years. Reasons for the development of resistance to this type of treatment are still unclear, and the insensitivity to drugs is associated with very poor prognosis in patients with all subtypes of myelodysplastic syndrome. Such data and the presence of numerous genetic and epigenetic mechanisms for the development of this pathology have prompted the use of combinations of drugs with different application points and are relevant in terms of research. In the literature review, the results of clinical studies on the use of hypomethylating agents in patients with MDS of low and high risk, as in monotherapy and combined schemes are presented. The nearest prospect of treatment of myelodysplastic syndrome is the creation of new treatment regimens based on a combination of drugs of different pathogenetic direction for the elimination of the dysplastic clone in order to achieve not only long-term remissions, but also lengthening the duration of overall survival, especially for patients with high risk myelodysplastic syndrome.

DNA methyltransferase expression in triple-negative breast cancer predicts sensitivity to decitabine

Triple-negative breast cancer (TNBC) is a heterogeneous disease with poor prognosis that lacks targeted therapies, especially in patients with chemotherapy-resistant disease. Since DNA methylation-induced silencing of tumor suppressors is common in cancer, reversal of promoter DNA hypermethylation by 5-aza-2'-deoxycytidine (decitabine), an FDA-approved DNA methyltransferase (DNMT) inhibitor, has proven effective in treating hematological neoplasms. However, its antitumor effect varies in solid tumors, stressing the importance of identifying biomarkers predictive of therapeutic response. Here, we focused on the identification of biomarkers to select decitabine-sensitive TNBC through increasing our understanding of the mechanism of decitabine action. We showed that protein levels of DNMTs correlated with response to decitabine in patient-derived xenograft (PDX) organoids originating from chemotherapy-sensitive and -resistant TNBCs, suggesting DNMT levels as potential biomarkers of response. Furthermore, all 3 methytransferases, DNMT1, DNMT3A, and DNMT3B, were degraded following low-concentration, long-term decitabine treatment both in vitro and in vivo. The DNMT proteins could be ubiquitinated by the E3 ligase, TNF receptor-associated factor 6 (TRAF6), leading to lysosome-dependent protein degradation. Depletion of TRAF6 blocked decitabine-induced DNMT degradation, conferring resistance to decitabine. Our study suggests a potential mechanism of regulating DNMT protein degradation and DNMT levels as response biomarkers for DNMT inhibitors in TNBCs.

The role of DNA methylation in ageing and cancer

The aim of the present review paper is to survey the literature related to DNA methylation, and its association with cancer and ageing. The review will outline the key factors, including diet, which modulate DNA methylation. Our rationale for conducting this review is that ageing and diseases, including cancer, are often accompanied by aberrant DNA methylation, a key epigenetic process, which is crucial to the regulation of gene expression. Significantly, it has been observed that with age and certain disease states, DNA methylation status can become disrupted. For instance, a broad array of cancers are associated with promoter-specific hypermethylation and concomitant gene silencing. This review highlights that hypermethylation, and gene silencing, of the EN1 gene promoter, a crucial homeobox gene, has been detected in various forms of cancer. This has led to this region being proposed as a potential biomarker for diseases such as cancer. We conclude the review by describing a recently developed novel electrochemical method that can be used to quantify the level of methylation within the EN1 promoter and emphasise the growing trend in the use of electrochemical techniques for the detection of aberrant DNA methylation.

Systematic review of azacitidine regimens in myelodysplastic syndrome and acute myeloid leukemia

Background

5-Azacitidine administered as a 7-day dosing regimen (7–0-0) is approved in high risk IPSS myelodysplastic syndrome (MDS) patients. Alternative regimens such as a 5-day (5–0-0) or 7-day with a weekend break (5–2-2) are commonly used. No randomized controlled trial has been done directly comparing all three dosing regimens. The objective of this study was to compare the efficacies of the 5–0-0, 5–2-2, and 7–0-0 regimens in MDS and AML.

Methods

A systematic review was conducted using MEDLINE, EMBASE and CENTRAL. Eligible studies were randomized controlled trials (RCTs), observational prospective and retrospective studies. The primary clinical outcomes were Objective Response Rate (ORR) defined as the sum of complete response (CR), partial response (PR), and hematological improvement (HI) as defined by the IWG 2006 criteria. A meta-analysis of simple proportions was conducted using a random effects model with weights defined according to Laird and Mosteller. Comparisons between groups were not attempted due to the heterogeneity of study designs.

Results

The only RCT directly comparing alternative azacitidine regimens showed no difference in ORR between the 5–0-0 and 5–2-2 regimens. All other RCTs compared a dosing regimen to conventional care. The pooled proportion of ORR was 44.8% with 95% CI (42.8%, 45.5%) for 7–0-0, 41.2% with 95% CI (39.2%, 41.9%) for 5–0-0, and 45.8% with 95% CI (42.6%, 46.4%) for 5–2-2.

Conclusions

Indirect comparison of alternative azacitidine dosing regimens in MDS and AML shows a benefit for the 7-day regimen in attaining ORR. Additional RCTs are required to definitively address this comparison.

Electronic supplementary material

The online version of this article (10.1186/s12878-017-0094-8) contains supplementary material, which is available to authorized users.

A Summary of the Biological Processes, Disease-Associated Changes, and Clinical Applications of DNA Methylation

DNA methylation at cytosines followed by guanines, CpGs, forms one of the multiple layers of epigenetic mechanisms controlling and modulating gene expression through chromatin structure. It closely interacts with histone modifications and chromatin remodeling complexes to form the local genomic and higher-order chromatin landscape. DNA methylation is essential for proper mammalian development, crucial for imprinting and plays a role in maintaining genomic stability. DNA methylation patterns are susceptible to change in response to environmental stimuli such as diet or toxins, whereby the epigenome seems to be most vulnerable during early life. Changes of DNA methylation levels and patterns have been widely studied in several diseases, especially cancer, where interest has focused on biomarkers for early detection of cancer development, accurate diagnosis, and response to treatment, but have also been shown to occur in many other complex diseases. Recent advances in epigenome engineering technologies allow now for the large-scale assessment of the functional relevance of DNA methylation. As a stable nucleic acid-based modification that is technically easy to handle and which can be analyzed with great reproducibility and accuracy by different laboratories, DNA methylation is a promising biomarker for many applications.

Can we consider discontinuation of hypomethylating agents in patients with myelodysplastic syndrome : a retrospective study from The Korean Society of Hematology AML/MDS Working Party

It is often difficult to continue treatment with hypomethylating agent(HMA) in clinical practice because of problems such as toxicities, poor economics, etc. We compared clinical outcomes of those patients who continued HMA and those who discontinued HMA because of other causes, and evaluated factors associated with survival in those patients who discontinued HMA.

Patients were divided into two groups: treatment failure, those who stopped treatment due to disease progression; and discontinuation, those who discontinued treatment because of other causes.

The median progression free survival(PFS) was 9.2 months (range 7.7 – 10.7 months) vs 28.9 months (range 22.6 – 35.2) in the treatment failure and discontinuation groups, respectively (P < 0.001). In a multivariate analysis, a lower risk by WPSS was an independent predictive factor for a longer PFS, and a lower risk by WPSS and median number of HMA cycles greater than seven were independent predictive factors for longer overall survival(OS) only in the discontinuation group.

Patients who discontinued HMA without disease progression showed a prolonged survival than those who failed HMA treatment. Especially, a lower risk by WPSS and longer duration of HMA treatment may be predictive factors for a longer PFS and OS in patients who discontinued HMA.

Azacitidine in adult patients with acute myeloid leukemia

Azacitidine is recommended front-line treatment for older patients with acute myeloid leukemia (AML) who are not candidates for intensive treatment regimens, and was recently granted approval in the European Union for treatment of adult AML. Reviewed here is azacitidine experience in AML, including: mechanistic and pharmacokinetic data; safety and efficacy in controlled trials; treatment effects in AML subpopulations defined by disease characteristics; experience in unselected patients treated in the community setting; clinical outcomes relative to other approved AML therapies; and experience with azacitidine-based combination treatment regimens. Collectively, these data suggest that (a) azacitidine may prolong overall survival to a similar or greater extent than do other approved AML treatments, but with less toxicity, (b) azacitidine may be the preferred treatment option for older patients with unfavorable cytogenetics, and (c) experience and outcomes with azacitidine in the clinic are similar to those seen in clinical trials. Continued investigation of combination regimens on an azacitidine backbone is warranted.

A phase 1b/2b multicenter study of oral panobinostat plus azacitidine in adults with MDS, CMML or AML with ⩽30% blasts

Treatment with azacitidine (AZA), a demethylating agent, prolonged overall survival (OS) vs conventional care in patients with higher-risk myelodysplastic syndromes (MDS). As median survival with monotherapy is <2 years, novel agents are needed to improve outcomes. This phase 1b/2b trial (n=113) was designed to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D) of panobinostat (PAN)+AZA (phase 1b) and evaluate the early efficacy and safety of PAN+AZA vs AZA monotherapy (phase 2b) in patients with higher-risk MDS, chronic myelomonocytic leukemia or oligoblastic acute myeloid leukemia with <30% blasts. The MTD was not reached; the RP2D was PAN 30 mg plus AZA 75 mg/m². More patients receiving PAN+AZA achieved a composite complete response ([CR)+morphologic CR with incomplete blood count+bone marrow CR (27.5% (95% CI, 14.6–43.9%)) vs AZA (14.3% (5.4–28.5%)). However, no significant difference was observed in the 1-year OS rate (PAN+AZA, 60% (50–80%); AZA, 70% (50–80%)) or time to progression (PAN+AZA, 70% (40–90%); AZA, 70% (40–80%)). More grade 3/4 adverse events (97.4 vs 81.0%) and on-treatment deaths (13.2 vs 4.8%) occurred with PAN+AZA. Further dose or schedule optimization may improve the risk/benefit profile of this regimen.

Drugging the pain epigenome

More than 20% of adults worldwide experience different types of chronic pain, which are frequently associated with several comorbidities and a decrease in quality of life. Several approved painkillers are available, but current analgesics are often hampered by insufficient efficacy and/or severe adverse effects. Consequently, novel strategies for safe, highly efficacious treatments are highly desirable, particularly for chronic pain. Epigenetic mechanisms such as DNA methylation, histone modifications and microRNAs (miRNAs) strongly affect the regulation of gene expression, potentially for long periods over years or even generations, and have been associated with pathophysiological pain. Several studies, mostly in animals, revealed that inhibitors of DNA methylation, activators and inhibitors of histone modification and modulators of miRNAs reverse a number of pathological changes in the pain epigenome, which are associated with altered expression of pain-relevant genes. This epigenetic modulation might then reduce the nociceptive response and provide novel therapeutic options for analgesic therapy of chronic pain states. However, a number of challenges, such as nonspecific effects and poor delivery to target cells and tissues, hinder the rapid development of such analgesics. In this Review, we critically summarize data on epigenetics and pain, focusing on challenges in clinical development as well as possible new approaches to the drug modulation of the pain epigenome.

Myelodysplastic Syndromes: Updates and Nuances

Myelodysplastic syndrome (MDS) is a heterogeneous, clonal stem cell disorder of the blood and marrow typically diagnosed based on the presence of persistent cytopenia(s), dysplastic cells, and genetic markers. Common issues that arise in the clinical management include difficulty confirming MDS diagnosis, lack of a standard approach with novel agents in MDS, and few prospective long-term, randomized controlled MDS clinical studies to guide allogeneic blood and marrow transplant. With the recent genetic characterization of MDS, certain aspects of these issues will be better addressed by integrating genetic data into clinical study design and clinical practice.

Comparative clinical effectiveness of azacitidine versus decitabine in older patients with myelodysplastic syndromes

The hypomethylating agents (HMAs) azacitidine and decitabine are both approved for treatment of myelodysplastic syndromes (MDS) in the USA. In Europe, decitabine is not approved due to lack of survival advantage in randomized trials. The two drugs have not been compared in clinical trials. We identified patients diagnosed with MDS between 2004 and 2011 from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database in the USA who received ≥ 10 doses of either HMA. We estimated survival from HMA initiation with Kaplan-Meier methods and used multivariate Cox proportional hazards models to adjust for covariates. Analyses controlled for histological subtype and we conducted a subset analysis limited to patients with refractory anaemia with excess blasts (RAEB). In 2025 HMA-treated patients, median survival was 15 months with no difference in survival based on the HMA received in adjusted analysis (decitabine versus azacitidine, hazard ratio = 1·06, 95% confidence interval: 0·94-1·19, P = 0·37). For RAEB patients (n = 523), median survival was 12 months, with no significant difference based on HMA received. No significant survival difference was found between azacitidine and decitabine in patients with MDS, including RAEB. Importantly, population-based survival of azacitidine-treated RAEB patients was substantially shorter than in the AZA-001 clinical trial (11 versus 24·5 months).

Vitamin C increases viral mimicry induced by 5-aza-2'-deoxycytidine

Vitamin C deficiency is found in patients with cancer and might complicate various therapy paradigms. Here we show how this deficiency may influence the use of DNA methyltransferase inhibitors (DNMTis) for treatment of hematological neoplasias. In vitro, when vitamin C is added at physiological levels to low doses of the DNMTi 5-aza-2'-deoxycytidine (5-aza-CdR), there is a synergistic inhibition of cancer-cell proliferation and increased apoptosis. These effects are associated with enhanced immune signals including increased expression of bidirectionally transcribed endogenous retrovirus (ERV) transcripts, increased cytosolic dsRNA, and activation of an IFN-inducing cellular response. This synergistic effect is likely the result of both passive DNA demethylation by DNMTi and active conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) by ten-eleven translocation (TET) enzymes at LTR regions of ERVs, because vitamin C acts as a cofactor for TET proteins. In addition, TET2 knockout reduces the synergy between the two compounds. Furthermore, we show that many patients with hematological neoplasia are markedly vitamin C deficient. Thus, our data suggest that correction of vitamin C deficiency in patients with hematological and other cancers may improve responses to epigenetic therapy with DNMTis.

Myelodysplastic Syndromes in the Elderly: Treatment Options and Personalized Management

Myelodysplastic syndromes (MDS) are typical diseases of the elderly, with a median age of 68-75 years at initial diagnosis. Demographic changes producing an increased proportion of elderly in our societies mean the incidence of MDS will rise dramatically. Considering the increasing number of treatment options, ranging from best supportive care to hematopoietic stem cell transplantation (HSCT), decision making is rather complex in this cohort of patients. Moreover, aspects of the aging process also have to be considered in therapy planning. Treatment of elderly MDS patients is dependent on the patient's individual risk and prognosis. Comorbidities play an essential role as predictors of survival and therapy tolerance. Age-adjusted models and the use of geriatric assessment scores are described as a basis for individualized treatment algorithms. Specific treatment recommendations for the different groups of patients are given. Currently available therapeutic agents, including supportive care, erythropoiesis-stimulating agents (ESAs), immune-modulating agents, hypomethylating agents, and HSCT are described in detail and discussed with a special focus on elderly MDS patients. The inclusion of elderly patients in clinical trials is of utmost importance to obtain data on efficacy and safety in this particular group of patients. Endpoints relevant for the elderly should be integrated, including maintenance of quality of life and functional activities as well as evaluation of use of healthcare resources.

A clinical-molecular update on azanucleoside-based therapy for the treatment of hematologic cancers

The azanucleosides azacitidine and decitabine are currently used for the treatment of acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) in patients not only eligible for intensive chemotherapy but are also being explored in other hematologic and solid cancers. Based on their capacity to interfere with the DNA methylation machinery, these drugs are also referred to as hypomethylating agents (HMAs). As DNA methylation contributes to epigenetic regulation, azanucleosides are further considered to be among the first true “epigenetic drugs” that have reached clinical application. However, intriguing new evidence suggests that DNA hypomethylation is not the only mechanism of action for these drugs. This review summarizes the experience from more than 10 years of clinical practice with azanucleosides and discusses their molecular actions, including several not related to DNA methylation. A particular focus is placed on possible causes of primary and acquired resistances to azanucleoside treatment. We highlight current limitations for the success and durability of azanucleoside-based therapy and illustrate that a better understanding of the molecular determinants of drug response holds great potential to overcome resistance.

The risk of infections in patients with myelodysplastic syndromes in 2016

INTRODUCTION

The medical treatment of patients suffering from myelodysplastic syndromes has significantly changed during the last ten years, and this may have impacted the epidemiology of infectious complications. Some 'real world' experiences raised the issue of infections in this setting and the possible negative consequences for patients and health system: the higher the rate of hospitalizations and need for anti-infective therapies, the higher the treatment delays/withdrawal and consecutive the worse the outcome.

AREAS COVERED

The main epidemiological data on myelodysplastic patients are reviewed. Potential risk factors are described, including those related to the disease itself, patient's characteristics, health conditions and the environment. Expert commentary: The complexity of MDS treatment is expected to increase further, with the introduction of other drugs and combined therapies. Defining the level of risk at time of treatment prescription will become more and more important, in order to better manage the infectious risk and the febrile events eventually occurring.

Infections in patients with acute myeloid leukemia treated with low-intensity therapeutic regimens: Risk factors and efficacy of antibiotic prophylaxis

Survival of acute myeloid leukemia (AML) patients, who are unfit for high-dose chemotherapy, has significantly improved with the advent of low-intensity therapeutic regimens (LITR, comprising decitabine, azacitidine, and low-dose cytarabine). However, infectious complications are common during LITR treatment and might hamper the beneficial effect of these drugs. In this study, we aimed to evaluate the incidence of and predisposing risk factors for infections during LITR treatment of AML, as well as the value of antibiotic prophylaxis within this setting. Therefore, we retrospectively analyzed 40 AML patients, treated with 215 cycles of LITR and analyzed putative risk factors by multivariate logistic regression. Infections occurred in 53/215 (25%) of LITR cycles, resulting in death in six patients. Of the parameters assessed at the start of each LITR cycle, transfusion dependence (p=0.008) and increased LDH (p=0.027) independently predicted the occurrence of infection. Most importantly, however, antibiotic prophylaxis was independently associated with a decreased rate of infectious complications (p=0.030). It was regularly performed in neutropenic patients and even managed to eliminate low neutrophil counts as risk factor in multivariate models. These data argue for the efficacy of antibiotic prophylaxis during LITR therapy of AML and suggest its further evaluation within a prospective clinical trial.

Spotlight on decitabine for myelodysplastic syndromes in Chinese patients

Myelodysplastic syndromes (MDSs) are a group of heterogeneous clonal hematopoietic stem cell malignancies with advanced median age. The silencing of tumor suppressor genes caused by DNA hypermethylation plays a crucial role in the pathogenesis of MDS. Decitabine, the available hypomethylating agent, is successfully used for the treatment and improves the outcome of MDS, and has become one of the most frequently administered disease-modifying therapies. With an aging population and a growing number of people exposed to benzene, the incidence of MDS has been increasing rapidly. The blinded regimen choice and the lack of a unified strategy create challenges for the treatment of MDS. Here, we present a review of clinical progress and prospects of decitabine treatment of MDS in the People’s Republic of China. We also discuss the optimization of therapy issues to improve the cure rate and prolong survival in patients with MDS.

Decitabine versus best supportive care in older patients with refractory anemia with excess blasts in transformation (RAEBt) - results of a subgroup analysis of the randomized phase III study 06011 of the EORTC Leukemia Cooperative Group and German MDS Study Group (GMDSSG)

In the European Organisation for Research and Treatment of Cancer (EORTC)/GMDSSG phase III trial 06011, we compared decitabine (15 mg/m(2) every 8 h for 3 days) with best supportive care (BSC) in patients ≥60 years with myelodysplastic syndromes (MDS) by French-American-British (FAB) criteria. Here, we reinvestigate trial 06011 for the activity and efficacy specifically in patients with refractory anemia with excess blasts in transformation (RAEBt). Response rates in the decitabine arm (N = 40) were as follows: complete or partial remission, 15 %; hematologic improvement, 15 %; resistant disease, 30 %. RAEBt patients in the decitabine arm had longer progression-free survival (PFS; hazard ratio (HR) 0.30, 95 % confidence interval (CI) 0.18-0.51; median, 6.2 vs 2.8 months) and overall survival (OS; HR 0.68, 95 % CI 0.42-1.11; median, 8.0 vs 6.0 months) than in the BSC arm (N = 35). Censoring at allogeneic hematopoietic stem cell transplantation, the OS difference between the treatment groups increased, particularly among patients aged 60-74 years (HR 0.48, 95 % CI 0.26-0.89). After regrouping the study cohort according to World Health Organization (WHO) criteria, patients with acute myeloid leukemia (AML) (i.e., ≥20 % blasts) in the decitabine arm (N = 27) also had longer PFS than in the BSC arm (N = 23) (HR 0.46, 95 % CI 0.26-0.83; median, 6.2 vs 2.8 months). In conclusion, 3-day decitabine displays clinical activity and efficacy in MDS and/or AML with 5-30 % blood or 20-30 % marrow blasts.

Multiple structural and epigenetic defects in the human leukocyte antigen class I antigen presentation pathway in a recurrent metastatic melanoma following immunotherapy

Scant information is available about the molecular basis of multiple HLA class I antigen-processing machinery defects in malignant cells, although this information contributes to our understanding of the molecular immunoescape mechanisms utilized by tumor cells and may suggest strategies to counteract them. In the present study we reveal a combination of IFN-γ-irreversible structural and epigenetic defects in HLA class I antigen-processing machinery in a recurrent melanoma metastasis after immunotherapy. These defects include loss of tapasin and one HLA haplotype as well as selective silencing of HLA-A3 gene responsiveness to IFN-γ. Tapasin loss is caused by a germ-line frameshift mutation in exon 3 (TAPBP(684delA)) along with a somatic loss of the other gene copy. Selective silencing of HLA-A3 gene and its IFN-γ responsiveness is associated with promoter CpG methylation nearby site-α and TATA box, reversible after DNA methyltransferase 1 depletion. This treatment combined with tapasin reconstitution and IFN-γ stimulation restored the highest level of HLA class I expression and its ability to elicit cytotoxic T cell responses. These results represent a novel tumor immune evasion mechanism through impairing multiple components at various levels in the HLA class I antigen presentation pathway. These findings may suggest a rational design of combinatorial cancer immunotherapy harnessing DNA demethylation and IFN-γ response.

Integrative network modeling approaches to personalized cancer medicine

The ability to collect millions of molecular measurements from patients is a now a reality for clinical medicine. This reality has created the challenge of how to integrate these vast amounts of data into models that accurately predict complex pathophysiology and can translate this complexity into clinically actionable outputs. Integrative informatics and data-driven approaches provide a framework for analyzing large-scale datasets and combining them into multiscale models that can be used to determine the key drivers of disease and identify optimal therapies for treating tumors. In this perspective we discuss how an integrative modeling approach is being used to inform individual treatment decisions, highlighting a recent case report that illustrates the challenges and opportunities for personalized oncology.