Somatic mutations of activating signalling, transcription factor, and tumour suppressor are a precondition for leukaemia transformation in myelodysplastic syndromes.

The transformation biology of secondary acute myeloid leukaemia (AML) from myelodysplastic syndromes (MDSs) is still not fully understood. We performed paired self-controlled sequencing, including targeted, whole exome, and single-cell RNA sequencing, in a cohort of MDS patients to search for AML transformation-related mutations (TRMs). Thirty-nine target genes from paired samples from 72 patients with MDS who had undergone AML transformation were analysed. The targeted sequencing results showed that 64 of 72 (88.9%) patients presented TRMs involving signalling pathway activation, transcription factors, or tumour suppressors. Of the 64 patients, most of the TRMs (62.5%, 40 cases) emerged at the leukaemia transformation point. Paired whole exome sequencing showed some presumptive TRMs, which were not included in the reference targets in three patients. No patient developed AML only by acquiring mutations involved in epigenetic modulation or ribonucleic acid splicing. Single-cell sequencing indicated that the activating cell signalling route was related to TRMs in one paired sample. Targeted sequencing defined TRMs were limited to a small set of seven genes (in the order: NRAS/KRAS, CEBPA, TP53, FLT3, CBL, PTPN11, and RUNX1, accounting for nearly 90.0% of the TRMs). In conclusion, somatic mutations involved in signalling, transcription factors, or tumour suppressors appeared to be a precondition for AML transformation from MDS.

CSF3R T618I, SETBP1 G870S, SRSF2 P95H, and ASXL1 Q780* tetramutation co-contribute to myeloblast transformation in a chronic neutrophilic leukemia.

Chronic neutrophilic leukemia (CNL) is a rare but serious myeloid malignancy. In a review of reported cases for WHO-defined CNL, CSF3R mutation is found in about 90% cases and confirmed as the molecular basis of CNL. Concurrent mutations are observed in CSF3R-mutated CNL patients, including ASXL1, SETBP1, SRSF2, JAK2, CALR, TET2, NRAS, U2AF1, and CBL. Both ASXL1 and SETBP1 mutations in CNL have been associated with a poor prognosis, whereas, SRSF2 mutation was undetermined. Our patient was a 77-year-old man and had no significant past medical history and symptoms with leukocytosis. Bone marrow (BM) aspirate and biopsy revealed a markedly hypercellular marrow with prominent left-shifted granulopoiesis. Next-generation sequencing (NGS) of DNA from the BM aspirate of a panel of 28 genes, known to be pathogenic in MDS/MPN, detected mutations in CSF3R, SETBP1, and SRSF2, and a diagnosis of CNL was made. The patient did not use a JAK-STAT pathway inhibitor (ruxolitinib) but started on hydroxyurea and alpha-interferon and developed pruritus after 4 months of diagnosis and nasal hemorrhage 1 month later. Then, the patient was diagnosed with CNL with AML transformation and developed intracranial hemorrhage and died. We repeated NGS and found that three additional mutations were detected: ASXL1, PRKDC, MYOM2; variant allele frequency (VAF) of the prior mutations in CSF3R, SETBP1, and SRSF2 increased. The concurrence of CSF3RT618I, ASXL1, SETBP1, and SRSF2 mutation may be a mutationally detrimental combination and contribute to disease progression and AML transformation, as well as the nonspecific treatment of hydroxyurea and alpha-interferon, but the significance and role of PRKDC and MYOM2 mutations were not undetermined.

Acute myeloid leukemia with translocation (1;21).

Advancement in genetic and molecular biology techniques has greatly helped our understanding of various diseases, especially hematological disorders. We describe a case of primary myelofibrosis (PMF) that transformed into acute myeloid leukemia with a very rare and unusual genetic translocation of (1;21). There are only five reported cases of this translocation in acute myeloid leukemia (AML) or myelodysplastic syndrome but none of them transformed from PMF. This case not only highlights the importance of rare genetic translocations but also provides the natural history of the disease and its poor prognosis. To the best of our knowledge our patient is the first reported case of AML transformed from PMF to have this unique translocation of (1;21).

Cytogenetic clonal evolution in myelodysplastic syndromes is associated with inferior prognosis.

BACKGROUND: The karyotype of bone marrow cells at the time of diagnosis is a strong prognostic parameter for overall survival as well as acute myeloid leukemia (AML) progression in patients with myelodysplastic syndromes (MDS). However, to the authors' knowledge, few data exist regarding the prognostic impact of cytogenetic clonal evolution during the course of MDS. METHODS: The authors evaluated follow-up karyotype analyses in 549 patients from the Dusseldorf MDS Registry. RESULTS: Clonal evolution was detectable in 24% of the entire cohort and in 18% of 294 patients receiving best supportive care. The authors noted a clear adverse effect of clonal evolution on the risk of leukemic transformation (hazard ratio, 2.233; P = .036) and overall survival (hazard ratio, 3.677; P<.001). The authors also analyzed the prognostic influence of subclones detectable at the time of diagnosis. Again, such a finding was associated with a significantly shorter overall survival and a higher 5-year-probability of acute myeloid leukemia progression (30% vs 22%). CONCLUSIONS: The results of the current study support the belief that follow-up karyotype analyses should be performed, especially in patients with lower-risk and intermediate-risk MDS, to identify those patients who are at higher risk of disease progression and therefore might benefit from earlier or more intensive treatment. Cancer 2017;123:4608-4616. © 2017 American Cancer Society.

Predicting leukemic transformation in myelodysplastic syndrome using a transcriptomic signature.

Background: For prediction on leukemic transformation of MDS patients, emerging model based on transcriptomic datasets, exhibited superior predictive power to traditional prognostic systems. While these models were lack of external validation by independent cohorts, and the cell origin (CD34+ sorted cells) limited their feasibility in clinical practice. Methods: Transformation associated co-expressed gene cluster was derived based on GSE58831 ('WGCNA' package, R software). Accordingly, the least absolute shrinkage and selection operator algorithm was implemented to establish a scoring system (i.e., MDS15 score), using training set (GSE58831 originated from CD34+ cells) and testing set (GSE15061 originated from unsorted cells). Results: A total of 68 gene co-expression modules were derived, and the 'brown' module was recognized to be transformation-specific (R2 = 0.23, p = 0.005, enriched in transcription regulating pathways). After 50,000-times LASSO iteration, MDS15 score was established, including the 15-gene expression signature. The predictive power (AUC and Harrison's C index) of MDS15 model was superior to that of IPSS/WPSS in both training set (AUC/C index 0.749/0.777) and testing set (AUC/C index 0.933/0.86). Conclusion: By gene co-expression analysis, the crucial gene module was discovered, and a novel prognostic system (MDS15) was established, which was validated not only by another independent cohort, but by a different cell origin.

Age, Blasts, Performance Status and Lenalidomide Therapy Influence the Outcome of Myelodysplastic Syndrome With Isolated Del(5q): A Study of 58 South American Patients.

BACKGROUND: Myelodysplastic Syndrome (MDS) with isolated deletion 5q is associated with a low risk to leukemic evolution and long overall survival (OS); it comprises 3%-4.5% of MDS cases in Latin America classified according to the World Health Organization 2008. This study aims to describe clinical, laboratory and the outcome of patients according to the newest World Health Organization 2016 proposal. METHODS: We retrospectively reviewed patients from four Brazilian (BR) and four Argentinean (AR) centers diagnosed between 1999 and 2019. RESULTS: The 58 patients (16-AR and 42-BR) presented a median age of 67 (IQR 61-75) years old, women predominance (70.7%) and transfusion dependency (62.5%) at diagnosis. Median hemoglobin level was 8.1g/dL, 27.5% and 44.4% presented thrombocytosis and neutropenia, respectively. Bone marrow (BM) was predominantly hypercellular (43.1%) with 66% showing dysplasia >1 lineage and 37.9% with >2% of blasts. Deletion 5q was mostly isolated (79.3%) and a variety of abnormalities were observed in remaining cases. Most patients were treated with erythropoietin-stimulating agents (ESA), 18 with lenalidomide and 15 with thalidomide. Median follow-up was 7.6 years, with a median OS of 3.5 years and an 8-years leukemic evolution rate of 18.4%. Multivariate analysis showed that age >75 years (HR 2.19), ECOG ≥2 (HR 5.76), BM blasts >2% (HR 2.92) and lenalidomide treatment (HR 0.25) independently influenced the OS. CONCLUSION: Older age, worse performance status and higher percentage of blasts, that can be easily assessed, were associated to a worse prognosis. Also, our results corroborate the protective influence of lenalidomide in terms of OS in this South American series.

Real-World Data on Chronic Myelomonocytic Leukemia: Clinical and Molecular Characteristics, Treatment, Emerging Drugs, and Patient Outcomes.

Despite emerging molecular information on chronic myelomonocytic leukemia (CMML), patient outcome remains unsatisfactory and little is known about the transformation to acute myeloid leukemia (AML). In a single-center cohort of 219 CMML patients, we explored the potential correlation between clinical features, gene mutations, and treatment regimens with overall survival (OS) and clonal evolution into AML. The most commonly detected mutations were TET2, SRSF2, ASXL1, and RUNX1. Median OS was 34 months and varied according to age, cytogenetic risk, FAB, CPSS and CPSS-Mol categories, and number of gene mutations. Hypomethylating agents were administered to 37 patients, 18 of whom responded. Allogeneic stem cell transplantation (alloSCT) was performed in 22 patients. Two-year OS after alloSCT was 60.6%. Six patients received targeted therapy with IDH or FLT3 inhibitors, three of whom attained a long-lasting response. AML transformation occurred in 53 patients and the analysis of paired samples showed changes in gene mutation status. Our real-world data emphasize that the outcome of CMML patients is still unsatisfactory and alloSCT remains the only potentially curative treatment. However, targeted therapies show promise in patients with specific gene mutations. Complete molecular characterization can help to improve risk stratification, understand transformation, and personalize therapy.

Targeting PD-1/PD-L1 pathway in myelodysplastic syndromes and acute myeloid leukemia.

Myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) are clonal hematopoietic stem cell diseases arising from the bone marrow (BM), and approximately 30% of MDS eventually progress to AML, associated with increasingly aggressive neoplastic hematopoietic clones and poor survival. Dysregulated immune microenvironment has been recognized as a key pathogenic driver of MDS and AML, causing high rate of intramedullary apoptosis in lower-risk MDS to immunosuppression in higher-risk MDS and AML. Immune checkpoint molecules, including programmed cell death-1 (PD-1) and programmed cell death ligand-1 (PD-L1), play important roles in oncogenesis by maintaining an immunosuppressive tumor microenvironment. Recently, both molecules have been examined in MDS and AML. Abnormal inflammatory signaling, genetic and/or epigenetic alterations, interactions between cells, and treatment of patients all have been involved in dysregulating PD-1/PD-L1 signaling in these two diseases. Furthermore, with the PD-1/PD-L1 pathway activated in immune microenvironment, the milieu of BM shift to immunosuppressive, contributing to a clonal evolution of blasts. Nevertheless, numerous preclinical studies have suggested a potential response of patients to PD-1/PD-L1 blocker. Current clinical trials employing these drugs in MDS and AML have reported mixed clinical responses. In this paper, we focus on the recent preclinical advances of the PD-1/PD-L1 signaling in MDS and AML, and available and ongoing outcomes of PD-1/PD-L1 inhibitor in patients. We also discuss the novel PD-1/PD-L1 blocker-based immunotherapeutic strategies and challenges, including identifying reliable biomarkers, determining settings, and exploring optimal combination therapies.

A case of acute myeloid leukemia with e6a2 BCR-ABL fusion transcript acquired after progressing from chronic myelomonocytic leukemia.

Philadelphia (Ph) chromosome is a cytogenetic hallmark of chronic myeloid leukemia (CML). Most patients with CML harbor either the e13a2 or e14a2 BCR-ABL fusion product, while a small subset of the cases expresses e1a2 or e19a2 transcripts. We report a patient with chronic myelomonocytic leukemia (CMML), initially Ph chromosome negative at presentation, with rapid disease progression to acute myeloid leukemia (AML) and appearance of Ph chromosome and BCR-ABL e6a2, a very uncommon fusion transcript. The AML was refractory to treatment with subsequent emergence and dominance of a Ph negative leukemic clone. The patient expired shortly after disease progression.

A retrospective study of azacitidine treatment in patients with intermediate-2 or high risk myelodysplastic syndromes in a real-world clinical setting in Greece.

For patients with intermediate-2 or high risk [according to the International Prognostic Scoring System (IPSS)] myelodysplastic syndromes (MDS), azacitidine treatment offers hematologic improvement (HI) but also has the potential to modify the natural disease course. 'RETRO-AZA-MDS-001', a retrospective chart review study was conducted from February to November 2012 across 17 hematology hospital sites of Greece, aiming to evaluate the clinical efficacy and safety profile of azacitidine in IPSS intermediate-2/high risk adult MDS patients in routine care. A total of 88 patients (median age 74.7 years), with a 6.6 month median (range 1.0-49.5) azacitidine treatment duration were enrolled. The overall response rate [complete response (CR), marrow CR and partial response] was 37.7% (23/61), while stable disease with HI was achieved by 21.3% (13/61). The HI rate was 33.0 % (29/88) and the AML transformation rate 6.8% (6/88). Of the transfusion-dependent patients, 7.3% (3/41) became transfusion-independent during azacitidine treatment. The incidence of non-serious and serious adverse events related to azacitidine was 50.0 and 42.0%, respectively. Patients not receiving prior ESA therapy were expected to be 7.6 times more likely to achieve a clinical response (p = 0.012). The study corroborates the favorable risk-benefit profile of azacitidine for intermediate-2/high risk MDS patients in routine clinical practice.