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  • Hypomethylating agents (HMA), such as azacytidine (AZA) and decitabine (DAC), are epigenetic therapies used to treat some patients with acute myeloid leukaemia (AML) and myelodysplastic syndrome. HMAs act in a replication-dependent manner to remove DNA methylation from the genome. However, AML cells targeted by HMA therapy are often quiescent within the bone marrow, where oxygen levels are low. In this study, we investigate the effects of hypoxia on HMA responses in AML cells.

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  • Triple-negative breast cancer (TNBC) is recognized as the most aggressive subtype of breast cancer. Epigenetic silencing, such as DNA methylation mediated by DNA methyltransferases (DNMTs) plays key roles in TNBC tumorigenesis. Hypomethylating agents (HMAs) such as azacitidine, decitabine, and guadecitabine are key inhibitors of DNMTs, and accumulating evidence has shown their immunogenicity properties. In this review, the efficacy and anti-tumor immune responses triggered by HMAs in TNBC are presented and discussed. Essentially, overexpression of DNMTs is associated with poor prognosis and reduced TNBC survival rates, and these effects are negated by HMAs. In particular, HMAs could reverse epigenetic silencing of tumor suppressor genes and enhance immune recognition of TNBC cells. Clinical trials of HMAs in TNBCs are limited but early-stage trials indicate that HMAs are safe and tolerable. More clinical studies are required to establish the effectiveness of HMAs against the disease, as supported by preclinical data substantiating their effectiveness especially guadecitabine. Future research should focus on optimizing dosing and exploring combinations with immunotherapies to maximize the potential of HMAs in TNBC treatment.

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  • Poly (ADP-Ribose) polymerase inhibitors are approved for treatment of tumors with BRCA1/2 and other homologous recombination repair (HRR) mutations. However, clinical responses are often not durable and treatment may be detrimental in advanced cancer due to excessive toxicities. Thus we are seeking alternative therapeutics to enhance PARP-directed outcomes. In an effort to expand the clinical use of PARP inhibitors to HRR proficient tumors, several groups have tested combinations of DNA methyltransferase inhibitors and PARP inhibitors. While this approach attenuated tumor cell proliferation in preclinical studies, subsequent clinical trials revealed little benefit. We hypothesized that benefit for this drug combination would only be specific to HRR deficient tumors, due to their inability to enact high fidelity DNA repair with subsequent cell death.

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  • There is a limited information available on the clinical characteristics, treatment patterns and outcomes on older patients diagnosed with Acute Myeloid Leukemia (AML) in Latin-America. This multicenter retrospective study analyzed 269 patients over 60 years of age diagnosed with AML in Colombia, using data from RENEHOC-PETHEMA registry, from 2009 to 2023. The median age at diagnosis was 70 years (Range:60-98), 55% were men, 61% had an ECOG < 2, and 75.5% had de novo AML. FLT3-ITD or NPM1 mutations were performed in 23.4% and 15.6% patients, and detected in 14.3% and 16.7% of cases, respectively. Treatment included intensive chemotherapy (IC) (36.8%), Low-Intensity Regimen Based on Low-Dose Cytarabine (LDAC-based) (12.6%), hypomethylating agents (HMAs, with/without venetoclax) (35.3%), and supportive care (15.2%). The overall survival (OS) rate was 35.2% at 1 year and 5.6% at 5 years (13.7% for IC, 9.4% for LDAC-based, and 0% for other treatments); with median OS of 8.2 months (10.6 months after IC, 8.8 months after non-IC, 8.9 months after azacitidine/decitabine, 8.2 months after azacitidine-venetoclax, and 1.9 months with supportive care). Only 1.5% of patients underwent a transplant in the first line. The Leukemia-free survival (LFS) rate was 45.8% at 1-year and 13.7% at 5-years (22.4% for IC, 9.4% and 0% for other treatments); with median LFS of 9.5 months (17.3 months after IC, 7.4 months after LDAC-based, and 10.8 months after HMA). This study provides new insights into the management of patients in Colombia, highlighting the need for a highly individualized approach in treating AML in elderly patients.

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  • How I Treat Higher-Risk MDS.

    Myelodysplastic syndromes/neoplasms (MDS) are a widely heterogenous group of myeloid malignancies characterized by morphologic dysplasia, a defective hematopoiesis, and recurrent genetic abnormalities. The original and revised International Prognostic Scoring Systems (IPSS) have been used to risk-stratify patients with MDS to guide treatment strategies. In higher-risk MDS, the therapeutic approach is geared toward delaying leukemic transformation and prolonging survival. For over a decade, the hypomethylating agents azacitidine and decitabine have been the standard of care and, when feasible, an allogeneic hematopoietic stem cell transplantation (AHSCT) should be considered. However, the IPSS scoring systems solely rely on clinical, morphological, and cytogenetic features and do not account for somatic mutations present in over 80% of cases. These genetic abnormalities have been shown to play a crucial role in prognostication, prompting the development of molecular IPSS, and the integration of genomic features into MDS classification systems in recent years. In this review, we delineate our approach to higher-risk MDS in the context of updated classifications and the latest prognostication tools. We employ illustrative clinical cases to support our discussion and share insights from recent clinical trials, highlighting lessons learned.

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  • Cadmium (Cd) is a widely available metal that has been found to have a role in causing nonalcoholic fatty liver disease (NAFLD). However, the detailed toxicological targets and mechanisms by which Cd causes NAFLD are unknown. Therefore, the present work aims to reveal the main targets of action, cellular processes, and molecular pathways by which cadmium causes NAFLD. As shown in the bioinformatics analysis, there were 74 main targets of action for cadmium-induced NAFLD, hemopoietic cell kinase (HCK), EPH receptor A2 (EPHA2), MYC proto-oncogene (MYC), lysyl oxidase (LOX), dipeptidyl peptidase 7 (DPP7), nuclear factor erythroid 2-related factor 2 (NFE2L2), dual specificity phosphatase 6 (DUSP6), CD2 cytoplasmic tail binding protein 2 (CD2BP2), notch receptor 3 (NOTCH3), and phospholipase A2 group IVA (PLA2G4A) were screened as core genes. Testing these core genes in other databases, three differentially expressed genes, HCK, MYC, and DUSP6 were verified and used as targets for drug prediction in DsigDB; decitabine and retinoic acid were screened as potential therapeutic drugs for NAFLD based on the p-value and the combined score. The results of molecular docking showed that the predicted drugs can bind well to the core targets. In conclusion, cadmium is associated with NAFLD; the identified cadmium-toxicity targets, HCK, MYC, and DUSP6, may serve as biomarkers for the diagnosis of NAFLD and predicted drugs, decitabine and retinoic acid may have a potential role in the treatment of NAFLD.

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  • Liquid-Liquid Phase Separation (LLPS) is a process involved in the formation of established organelles and various condensates that lack membranes; however, the relationship between LLPS and Ulcerative Colitis (UC) remains unclear.

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  • Advancing Drug Development in Myelodysplastic Syndromes.

    Myelodysplastic syndromes/neoplasms (MDS) are heterogeneous stem cell malignancies characterized by poor prognosis and no curative therapies outside of allogeneic hematopoietic stem cell transplantation. Despite some recent approvals by the United States Food and Drug Administration (FDA), (e.g., luspatercept, ivosidenib, decitabine/cedazuridine and imetelstat), there has been little progress in the development of truly transformative therapies for the treatment of patients with MDS. Challenges to advancing drug development in MDS are multifold but may be grouped into specific categories including criteria for risk stratification and eligibility, response definitions, time-to-event endpoints, transfusion endpoints, functional assessments, and biomarker development. Strategies to address these challenges and optimize future clinical trial design for patients with MDS are presented here.

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  • Epigenetic dysregulation is a common feature of cancer. Promoter demethylation of tumor-promoting genes and global DNA hypomethylation may trigger tumor progression. Epigenetic changes are unstable; thus, research has focused on detecting remedies that target epigenetic regulators. Previous studies have suggested that concordantly targeting hypomethylation and hypermethylation is beneficial for suppressing both the oncogenic and pro-metastatic functions of cancer cells. Therefore, we aimed to investigate the effect of a combination of S-adenosylmethionine (SAM) and the demethylating agent decitabine on prostate cancer cells. Prostate cancer cells (PC-3) were treated with SAM, decitabine, or a combination of both. Proliferation, migration, invasion, and methylation assays were also performed. A transcriptome study was conducted to detect different gene clusters between the treatment groups, followed by analyses using the Kyoto Encyclopedia of Genes and Genomes pathway and ingenuity pathway analysis. Finally, to gain information on differential gene expression, promoter methylation studies were performed. Groups treated with decitabine, SAM, or their combination showed reduced proliferative capacity. The decitabine-treated group showed a marginal increase in cell migration and invasion, whereas the SAM-treated and combination treatment groups showed reduced invasion and migration potential. Methylation assays demonstrated the restoration of decitabine-induced demethylation in prostate cancer samples, whereas the transcriptome study revealed the upregulation of different gene clusters between the treatment groups. Methylation studies confirmed that SAM could restore the decitabine-induced demethylation of proto-oncogenes, but it did not induce the re-methylation of tumor-suppressor genes. Combination treatment with SAM and decitabine had an additive effect and did not nullify each other.

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  • Hypermethylation of tumor suppressor genes is a hallmark of leukemia. The hypomethylating agent decitabine covalently binds, and degrades DNA (cytosine-5)-methyltransferase 1 (DNMT1). Structural similarities within DNA-binding domains of DNMT1, and the leukemic driver histone-lysine N-methyltransferase 2A (KMT2A) suggest that decitabine might also affect the latter. In acute lymphoblastic leukemia (ALL) cell lines, and xenograft models, we observed increased DNMT1, and KMT2A expression in response to decitabine-induced demethylation. Strikingly, KMT2A protein expression was diminished in all cell lines that experienced DNMT1 degradation. Moreover, only cells with reduced KMT2A protein levels showed biological effects following decitabine treatment. KMT2A wild-type, and rearranged cells were locked in G2 and G1 cell cycle phases, respectively, likely due to p27/p16 activation. Primary sample gene expression profiling confirmed different patterns between KMT2A wild-type, and translocated cells. This newly discovered decitabine mode of action via KMT2A degradation evokes anti-leukemic activity in adult ALL cells, and can act synergistically with menin inhibition. Following the successful clinical implementation of decitabine for acute myeloid leukemia, the drug should be considered a potential promising addition to the therapeutic portfolio for ALL as well.

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