Programmed Cell Death Deregulation in BCR-ABL1-Negative Myeloproliferative Neoplasms

BCR-ABL1-negative myeloproliferative neoplasms are classically represented by primary myelofibrosis, polycythemia vera, and essential thrombocythemia. These entities are stem cell-derived clonal disorders characterized by hematopoietic progenitor autonomy or hypersensitivity to cytokines, most of them presenting mutations in Janus kinase 2 (JAK2), calreticulin (CALR), or myeloproliferative leukemia virus oncogene (MPL). Deregulation of pro- and antiapoptotic genes is also claimed as an important mechanism involved in cell resistance to cell death and accumulation of myeloid cells in myeloproliferative neoplasms. Apoptosis, as one of the best-characterized types of programmed cell death, has a clear role in hematopoiesis control. However, the exact pathways affected in BCR-ABL1-negative myeloproliferative neoplasms have not yet been fully clarified. This chapter will explore the modifications affecting programmed cell death pathways involved in myeloid proliferation and how these alterations might be exploited in single or combined targeted therapeutic strategies

Labile plasma iron levels predict survival in patients with lower-risk Myelodysplastic syndromes

Red blood cell transfusions remain one of the cornerstones in supportive care of lower-risk patients with myelodysplastic syndromes. We hypothesized that patients develop oxidant mediated tissue injury through the formation of toxic iron species, caused either by red blood cell transfusions or by ineffective erythropoiesis. We analyzed serum samples from 100 lower-risk patients with myelodysplastic syndromes at six-month intervals for transferrin saturation, hepcidin-25, growth differentiation factor 15, soluble transferrin receptor, non-transferrin bound iron and labile plasma iron in order to evaluate temporal changes in iron metabolism and presence of potentially toxic iron species and their impact on survival. Hepcidin levels were low in 34 patients with ringed sideroblasts compared to 66 patients without. Increases of hepcidin and non-transferrin bound iron levels were visible early in follow-up of all transfusion dependent patient groups. Hepcidin levels significantly decreased over time in transfusion independent patients with ringed sideroblasts. Increased soluble transferrin receptor levels in transfusion-independent patients with ringed sideroblasts confirmed the presence of ineffective erythropoiesis and suppression of hepcidin production in these patients. Detectable labile plasma iron levels in combination with high transferrin saturation levels occurred almost exclusively in patients with ringed sideroblasts and all transfusion dependent patient groups. Detectable labile plasma iron levels in transfusion dependent patients without ringed sideroblasts were associated with decreased survival. IN CONCLUSION: toxic iron species occurred in all transfusion dependent patients and in transfusion independent patients with ringed sideroblasts. Labile plasma iron appeared to be a clinically relevant measure for potential iron toxicity and a prognostic factor for survival in transfusion dependent patients. This trial was registered at www.clinicaltrials.gov as #NCT00600860

Prognostic impact of a suboptimal number of analyzed metaphases in normal karyotype lower-risk MDS

Conventional karyotype is one of the most relevant prognostic factors in MDS. However, about 50% of patients with MDS have a normal karyotype. Usually, 20-25 normal metaphases (nMP) are considered to be optimal to exclude small abnormal clones which might be associated with poor prognosis. This study evaluated the impact of examining a suboptimal number of metaphases in patients recruited to the EUMDS Registry with low and intermediate-1 risk according to IPSS. Only 179/1049 (17%) of patients with a normal karyotype had a suboptimal number of nMP, defined as less than 20 metaphases analyzed. The outcome (overall survival and progression-free survival) of patients with suboptimal nMP was not inferior to those with higher numbers of analyzed MP both in univariate and multivariate analyses. For patients with an abnormal karyotype, 224/649 (35%) had a suboptimal number of MP assessed, but this did not impact on outcome. For patients with a normal karyotype and suboptimal numbers of analyzable metaphases standard evaluation might be acceptable for general practice, but we recommend additional FISH-analyses or molecular techniques, especially in candidates for intensive interventions

Novel dynamic outcome indicators and clinical endpoints in myelodysplastic syndrome; the European LeukemiaNet MDS Registry and MDS-RIGHT project perspective

Available evidence suggests that in most patients with LR-MDS the risk of death is not related to disease progression but is mainly attributable to non-leukemic death. 2,17 In addition, a proportion of these patients have prolonged survival that precludes the design of clinical trials adopting OS as a primary endpoint. These challenges have resulted in potentially biased assessment of the effectiveness and appropriate use of the available interventions in this patient population. The EUMDS Registry has identified novel meaningful outcome indicators and clinical endpoints, and reliable measures of response to HCI (Figure 4). The results of our analysis indicate that RBCT density is strongly associated with a decreased OS, even at relatively low dose densities. In addition, we observed that an early decrease in platelet count is an independent adverse prognostic indicator in LR-MDS, and combining relative platelet drop and transfusion dependency allows early identification of patients at risk of rapid progression, and may guide early therapeutic interventions, including allogeneic hematopoietic stem cell transplantation or experimental interventions. Taken together, these results indicate that regular RBCT requirement, early platelet count kinetics, and restriction in HRQoL are early independent and meaningful outcome indicators, and reliable measures of effectiveness of therapeutic interventions, evaluated in this set of studies. These findings support the integration of RBCT requirement and HRQoL in the general core outcome sets and in response criteria in patients with LR-MDS, and have important implications for clinical practice and the design of clinical endpoints. Our results strongly support the adoption of freedom from transfusion as a meaningful clinical endpoint in patients with LR-MDS. Anemia is the main determinant of therapeutic intervention in patients with LR-MDS, and ESA are recommended as first-line treatment for patients with symptomatic anemia. 10 The observational studies within the EUMDS Registry showed that the response rate, as well as the capacity of these agents to delay the onset of a regular RBCT need, is most pronounced in RBCT-naïve patients. These results identified early initiation of treatment with ESA as a major treatment response indicator, and indicate that ESA should be recommended in LR-MDS patients with symptomatic anemia before starting regular RBCT. After the onset of RBCT dependency, patients with LR-MDS are prone to long-term accumulation of iron. 1,43 The EUMDS Registry studies provided evidence that elevated LPI levels are associated with reduced survival in RBCT dependent patients, whereas iron chelation therapy normalizes LPI levels. These findings suggest that NTBI and LPI may serve as early indicators of iron toxicity and a means to measure the effectiveness of iron chelation therapy in patients with LR-MDS. However, qualified NTBI and LPI are only currently available in specialized laboratories. 44 Large observational cohorts with detailed clinical and laboratory data, like the EUMDS cohort, are the ideal framework in which to identify well defined MDS subtypes that may benefit from novel targeted treatments. An example of such a subtype is MDS with loss of parts of chromosome 5, namely del5q; these patients have a relatively favorable outcome on lenalidomide treatment. In order to identify homogeneous subsets of patients within MDS, preliminary evidence has suggested that recently identified mutations in splicing factors may recognize distinct disease entities within myeloid neoplasms. 45 Splicing modulators are now in pre-clinical testing, and are very likely to lead to the introduction of effective drugs for specific groups of MDS patients. Luspatercept, a specific inhibitor of growth and differentiation factor-11, a member of the transforming growth factor β superfamily, induced substantial improvement of anemia, especially in patients with ring sideroblasts. 46 Characterization of individual cases by new genetic markers (one of the main objectives of the MDS-RIGHT project) will allow refined classification of patients into biological subgroups that are expected to respond differently to therapeutic interventions to guide discontinuation of those interventions that are less effective or less cost-effective. The main question is whether RCT data and retrospective cohort data in selected tertiary care centers are representative of the 'real world' data of the older patients with LR-MDS in the general population. A careful comparison of the 'real world' data and the RCT data will be needed in order to provide a clear answer to these questions. Meanwhile, the current analyses of data collected over 10 years in the EUMDS Registry provides relevant and important information which could help assess prognosis and response to standard interventions in this older patient group

Cytomorphology review of 100 newly diagnosed lower-risk MDS patients in the European LeukemiaNet MDS (EUMDS) registry reveals a high inter-observer concordance

Objectives To examine contemporary survival patterns in the general population of patients diagnosed with chronic myeloid leukaemia (CML), and to identify patient groups with less than optimal outcomes. Design Prospective population-based cohort. Setting The UK's Haematological Malignancy Research Network (catchment population 3.6 million, with >2000 new haematological malignancies diagnosed annually). Participants All patients newly diagnosed with CML, from September 2004 to August 2011 and followed up to 31 March 2013. Main outcome measure Incidence and survival. Results With a median diagnostic age of 59 years, the CML age standardised (European) incidence was 0.9/100 000 (95% CIs 0.8 to 0.9), 5-year overall survival was 78.9% (72.3 to 84.0) and 5-year relative survival 88.6% (81.0 to 93.3). The efficacy of treatment across all ages was clearly demonstrated; the relative survival curves for those under 60 and over 60 years being closely aligned. Survival findings were similar for men and women, but varied with deprivation; the age and sex adjusted HR being 3.43 (1.89 to 6.22) for deprivation categories 4–5 (less affluent) versus 1–3 (more affluent). None of these differences were attributable to the biological features of the disease. Conclusions When therapy is freely provided, population-based survival for CML is similar to that reported in clinical trials, and age loses its prognostic significance. However, although most of the patients with CML now experience close to normal lifespans, those living in more deprived areas tend to have poorer outcomes, despite receiving the same clinical care. A significant improvement in overall population outcomes could be achieved if these socioeconomic differences, which may reflect the treatment compliance, could be eliminated

Early platelet count kinetics has prognostic value in lower-risk myelodysplastic syndromes

Prognosis of lower-risk (International Prognostic Scoring System [IPSS] low/intermediate-1) myelodysplastic syndrome (MDS) is heterogeneous and relies on steady-state assessment of cytopenias. We analyzed relative drops in neutrophil and platelet counts during the first 6 months of follow-up of lower-risk MDS patients. We performed a landmark analysis of overall survival (OS) of lower-risk MDS patients prospectively included in the European LeukaemiaNet MDS registry having a visit at 6 ± 1 month from inclusion to assess the prognostic relevance of relative drops in neutrophils and platelets, defined as (count at landmark - count at inclusion)/count at inclusion. Of 2102 patients, 807 were eligible for the stringent 6-month landmark analysis. Median age was 73 years. Revised IPSS was very low, low, and intermediate/higher in 26%, 43%, and 31% of patients, respectively. A relative drop in platelets >25% at landmark predicted shorter OS (5-year OS, 21.9% vs 48.6% with platelet drop ≤25%, P 25% had no significant impact on OS. We built a classifier based on red blood cell transfusion dependence (RBC-TD) and relative platelet drop >25% at landmark. Patients with none (62%), either (27%), or both criteria (11%) had 5-year OS of 53.3%, 32.7%, and 9.0%, respectively (P 25% and RBC-TD at 6 months from diagnosis provides an inexpensive and noninvasive way to predict outcome in lower-risk MDS. This study was registered at www.clinicaltrials.gov as #NCT00600860

Impact of treatment with iron chelation therapy in patients with lower-risk myelodysplastic syndromes participating in the European MDS registry

Iron overload due to red blood cell transfusions is associated with morbidity and mortality in lower-risk myelodysplastic syndrome patients. Many studies suggested improved survival after iron chelation therapy, but valid data are limited. The aim of this study was to assess the effect of iron chelation on overall survival and hematological improvement in lower-risk myelodysplastic syndrome patients in the European MDS registry. We compared chelated patients with a contemporary, non-chelated control group within the European MDS registry, that met the eligibility criteria for starting iron chelation. A Cox proportional hazards model was used to assess overall survival, treating receipt of chelation as a time-varying variable. Additionally, chelated and non-chelated patients were compared using a propensity-score matched model. Of 2200 patients, 224 received iron chelation. The hazard ratio and 95% confidence interval for overall survival for chelated patients, adjusted for age, sex, comorbidity, performance status, cumulative red blood cell transfusions, IPSS-R, and presence of ringed sideroblasts was 0.50 (0.34-0.74). The propensity-score analysis, matched for age, sex, country, red blood cell transfusion intensity, ferritin level, comorbidity, performance status, and IPSS-R and additionally corrected for cumulative red blood cell transfusions and presence of ringed sideroblasts, demonstrated a significantly improved overall survival for chelated patients with a hazard ratio of 0.42 (0.27-0.63) compared to non-chelated patients. Up to 39% of chelated patients reached an erythroid response. In conclusion, our results suggest that iron chelation may improve overall survival and hematopoiesis in transfused lower-risk myelodysplastic syndrome patients. This trial was registered at www.clinicaltrials.gov as #NCT00600860

Cooccurring V617F and R1063H mutations increase JAK2 signaling and neutrophilia in myeloproliferative neoplasms.

Although the concept of somatic driver mutations in myeloproliferative neoplasms (MPNs) represented by polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis is well established,1-3 the contribution of germline or co-occurring JAK2 variants to a particular MPN phenotype is less well understood.4,5 Recently, 2 germline JAK2 mutations, E846D and R1063H, were described in a case of hereditary erythrocytosis6 ; the same JAK2 R1063H variant was initially reported in 3 of 93 PV patients who were JAK2 V617F+. [...