ASXL1 mutations are associated with a response to alvocidib and 5-azacytidine combination in myelodysplastic neoplasms.

Inhibitors of anti-apoptotic BCL-2 family proteins in combination with chemotherapy and hypomethylating agents (HMAs) are promising therapeutic approaches in acute myeloid leukemia (AML) and high-risk myelodysplastic syndromes (MDS). Alvocidib, a cyclin-dependent kinase 9 (CDK9) inhibitor and indirect transcriptional repressor of the anti-apoptotic factor MCL-1, has previously shown clinical activity in AML. Availability of biomarkers for response to the alvocidib + 5- AZA could also extend the rationale of this treatment concept to high-risk MDS. In this study, we performed a comprehensive in vitro assessment of alvocidib and 5-AZA effects in n=45 high-risk MDS patients. Our data revealed additive cytotoxic effects of the combination treatment. Mutational profiling of MDS samples identified ASXL1 mutations as predictors of response. Further, increased response rates were associated with higher gene-expression of the pro-apoptotic factor NOXA in ASXL1 mutated samples. The higher sensitivity of ASXL1 mutant cells to the combination treatment was confirmed in vivo in ASXL1Y588X transgenic mice. Overall, our study demonstrated augmented activity for the alvocidib + 5-AZA combination in higher-risk MDS and identified ASXL1 mutations as a biomarker of response for potential stratification studies.

Myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions: reevaluation of the defining characteristics in a registry-based cohort.

In a registry-based analysis of 135 patients with "myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions" (MLN-TK; FIP1L1::PDGFRA, n = 78; PDGFRB, diverse fusions, n = 26; FGFR1, diverse, n = 9; JAK2, diverse, n = 11; ETV6::ABL1, n = 11), we sought to evaluate the disease-defining characteristics. In 81/135 (60%) evaluable patients, hypereosinophilia (>1.5 × 109/l) was observed in 40/44 (91%) FIP1L1::PDGFRA and 7/7 (100%) ETV6::ABL1 positive patients but only in 13/30 (43%) patients with PDGFRB, FGFR1, and JAK2 fusion genes while 9/30 (30%) patients had no eosinophilia. Monocytosis >1 × 109/l was identified in 27/81 (33%) patients, most frequently in association with hypereosinophilia (23/27, 85%). Overall, a blast phase (BP) was diagnosed in 38/135 (28%) patients (myeloid, 61%; lymphoid, 39%), which was at extramedullary sites in 18 (47%) patients. The comparison between patients with PDGFRA/PDGFRB vs. FGFR1, JAK2, and ETV6::ABL1 fusion genes revealed a similar occurrence of primary BP (17/104, 16% vs. 8/31 26%, p = 0.32), a lower frequency (5/87, 6% vs. 8/23, 35%, p = 0.003) of and a later progression (median 87 vs. 19 months, p = 0.053) into secondary BP, and a better overall survival from diagnosis of BP (17.1 vs. 1.7 years, p < 0.0008). We conclude that hypereosinophilia with or without monocytosis and various phenotypes of BP occur at variable frequencies in MLN-TK.

Significant improvement of bone marrow-derived MSC expansion from MDS patients by defined xeno-free medium.

BACKGROUND: Robust and reliable in vitro and in vivo models of primary cells are necessary to study the pathomechanisms of Myelodysplastic Neoplasms (MDS) and identify novel therapeutic strategies. MDS-derived hematopoietic stem and progenitor cells (HSPCs) are reliant on the support of bone marrow (BM) derived mesenchymal stroma cells (MSCs). Therefore, isolation and expansion of MCSs are essential for successfully modeling this disease. For the clinical use of healthy MSCs isolated from human BM, umbilical cord blood or adipose tissue, several studies showed that xeno-free (XF) culture conditions resulted in superior growth kinetics compared to MSCs cultured in the presence of fetal bovine serum (FBS). In this present study, we investigate, whether the replacement of a commercially available MSC expansion medium containing FBS with a XF medium is beneficial for the expansion of MSCs derived from BM of MDS patients which are often difficult to cultivate. METHODS: MSCs isolated from BM of MDS patients were cultured and expanded in MSC expansion medium with FBS or XF supplement. Subsequently, the impact of culture media on growth kinetics, morphology, immunophenotype, clonogenic potential, differentiation capacity, gene expression profiles and ability to engraft in immunodeficient mouse models was evaluated. RESULTS: Significant higher cell numbers with an increase in clonogenic potential were observed during culture of MDS MSCs with XF medium compared to medium containing FBS. Differential gene expression showed an increase in transcripts associated with MSC stemness after expansion with XF. Furthermore, immunophenotypes of the MSCs and their ability to differentiate into osteoblasts, adipocytes or chondroblasts remained stable. MSCs expanded with XF media were similarly supportive for creating MDS xenografts in vivo as MSCs expanded with FBS. CONCLUSION: Our data indicate that with XF media, higher cell numbers of MDS MSCs can be obtained with overall improved characteristics in in vitro and in vivo experimental models.

Inhibition of lysyl oxidases synergizes with 5-azacytidine to restore erythropoiesis in myelodysplastic and myeloid malignancies.

Limited response rates and frequent relapses during standard of care with hypomethylating agents in myelodysplastic neoplasms (MN) require urgent improvement of this treatment indication. Here, by combining 5-azacytidine (5-AZA) with the pan-lysyl oxidase inhibitor PXS-5505, we demonstrate superior restoration of erythroid differentiation in hematopoietic stem and progenitor cells (HSPCs) of MN patients in 20/31 cases (65%) versus 9/31 cases (29%) treated with 5-AZA alone. This effect requires direct contact of HSPCs with bone marrow stroma components and is dependent on integrin signaling. We further confirm these results in vivo using a bone marrow niche-dependent MN xenograft model in female NSG mice, in which we additionally demonstrate an enforced reduction of dominant clones as well as significant attenuation of disease expansion and normalization of spleen sizes. Overall, these results lay out a strong pre-clinical rationale for efficacy of combination treatment of 5-AZA with PXS-5505 especially for anemic MN.

Definition of factors associated with negative antibody response after COVID-19 vaccination in patients with hematological diseases.

COVID-19 in patients with hematological diseases is associated with a high mortality. Moreover, preventive vaccination demonstrated reduced efficacy and the knowledge on influencing factors is limited. In this single-center study, antibody levels of the SARS-CoV-2 spike protein were measured ≥ 2 weeks after 2nd COVID-19 vaccination with a concentration ≥ 0.8 U/mL considered positive. Between July and October 2021, in a total of 373 patients (median age 64 years, 44% women) with myeloid neoplasms (n = 214, 57%), lymphoid neoplasms (n = 124, n = 33%), and other diseases (n = 35, 10%), vaccination was performed with BNT162b2 (BioNTech), mRNA-1273 (Moderna), ChADOx1 (AstraZeneca), or a combination. A total of 229 patients (61%) were on active therapy within 3 months prior vaccination and 144 patients (39%) were previously treated or treatment naïve. Vaccination-related antibody response was negative in 56/373 patients (15%): in 39/124 patients with lymphoid neoplasms, 13/214 with myeloid neoplasms, and 4/35 with other diseases. Active treatment per se was not correlated with negative response. However, rituximab and BTK inhibitor treatment were correlated significantly with a negative vaccination response, whereas younger age and chronic myeloid leukemia (CML) disease were associated with positive response. In addition, 5 of 6 patients with myeloproliferative neoplasm (MPN) and negative vaccination response were on active treatment with ruxolitinib. In conclusion, a remarkable percentage of patients with hematological diseases had no response after 2nd COVID-19 vaccination. Multivariable analysis revealed important factors associated with response to vaccination. The results may serve as a guide for better protection and surveillance in this vulnerable patient cohort.

Preclinical evaluation of eltrombopag in a PDX model of myelodysplastic syndromes.

Preclinical research of myelodysplastic syndromes (MDSs) is hampered by a lack of feasible disease models. Previously, we have established a robust patient-derived xenograft (PDX) model for MDS. Here we demonstrate for the first time that this model is applicable as a preclinical platform to address pending clinical questions by interrogating the efficacy and safety of the thrombopoietin receptor agonist eltrombopag. Our preclinical study included n = 49 xenografts generated from n = 9 MDS patient samples. Substance efficacy was evidenced by FACS-based human platelet quantification and clonal bone marrow evolution was reconstructed by serial whole-exome sequencing of the PDX samples. In contrast to clinical trials in humans, this experimental setup allowed vehicle- and replicate-controlled analyses on a patient-individual level deciphering substance-specific effects from natural disease progression. We found that eltrombopag effectively stimulated thrombopoiesis in MDS PDX without adversely affecting the patients' clonal composition. In conclusion, our MDS PDX model is a useful tool for testing new therapeutic concepts in MDS preceding clinical trials.

[Mobbing Among Hospital Physicians]. / Mobbing unter Klinikärztinnen und -ärzten.

OBJECTIVES: Bullying in the workplace is considered an interpersonal stress factor. Occupational stress and mental health among physicians is increasingly becoming the focus of public attention. The extent to which mobbing plays a role in this has hardly been investigated yet. The aim of this study is to provide data on the prevalence of bullying among hospital physicians in Germany and possible correlations with occupational stress and mental health. METHODS: Within the framework of two cross-sectional studies, 692 hospital physicians in the field of psychiatry/psychotherapy (P/PT) and 667 hospital physicians in intensive care (IM) were interviewed at conferences. Standardized questionnaires on mobbing experience, occupational stress and mental health (single item from COPSOQ, BDI-II, ERI, MBI) were used. RESULTS: Bullying was experienced by 4.6% (n=61) of the respondents. IM and women physicians were more often affected (not significant) and correlations with occupational stress (ERI), overcommitment (OC), emotional exhaustion (MBI) and depression (BDI-II) were found. CONCLUSION: Our data on a large cohort of physicians in specialties with different exposure profiles show that a relevant proportion is affected by bullying and that bullying is related to the experience of occupational stress as well as mental health impairments. From this, implications for institutional and individual prevention and support services can be derived.

Humanized three-dimensional scaffold xenotransplantation models for myelodysplastic syndromes.

Patient-derived xenograft (PDX) models have emerged as versatile preclinical platforms for investigation of functional pathomechanisms in myelodysplastic syndromes (MDS) and other myeloid neoplasms. However, despite increasingly improved methodology, engraftment efficiencies frequently remain low. Humanized three-dimensional scaffold models (ossicle xenotransplantation models) in immunocompromised mice have recently been found to enable improved engraftment rates of healthy and malignant human hematopoiesis. We therefore interrogated the feasibility of using four different three-dimensional ossicle-based PDX models for application with primary MDS samples. In a fully standardized comparison, we evaluated scaffold materials such as Gelfoam, extracellular matrix (ECM), and human or xenogenous bone substance in comparison to intrafemoral (IF) co-injection of bone marrow (BM)-derived mesenchymal stromal cells (MSCs) and CD34+ hematopoietic stem and progenitor cells (HSPCs). Our study included13 primary MDS patient samples transplanted in parallel according to these five different conditions. Engraftment of MDS samples was assessed by flow cytometry, immunohistological staining, and molecular validation. We determined that three-dimensional ossicle-based methods achieved higher relative rates of engraftment and enabled long-term retrievability of patient-derived MSCs from implanted ossicles. In summary, HSPCs and MSCs derived from MDS BM, which did not significantly engraft in NSG mice after intrafemoral injection, were able to colonize humanized scaffold models. Therefore, these models are promising new xenotransplantation techniques for addressing preclinical and functional questions of the interaction between hematopoiesis and the BM niche in MDS.

Changes in Working Conditions and Mental Health Among Intensive Care Physicians Across a Decade.

Background: International studies have shown that among physicians working in intensive care, a relatively high level of work load, an elevated risk of developing burnout and reduced mental health are frequent. The implementation of a legislative intervention in Germany with the goal to reduce the working hours of physicians, offered an opportunity to investigate the potential influence of occupational conditions on stress and mental health. The present study investigates working conditions, occupational stress and burnout risk in two samples of German Intensive Care Physicians in 2006 and 2016. The aim was to assess how occupational and private stress factors influenced burnout and Effort-Reward-Imbalance indices over this time-period. Methods: Intensive care physicians were surveyed during the annual conference of their profession in two cross-sectional studies (10-year gap). Data on demographic (occupational, family), medical history, and mental health (burnout and Effort-Reward-Imbalance) were assessed by paper pencil questionnaires. Results: In total, N = 2,085 physicians participated (2006: N = 1,403, 2016: N = 695), with N = 1,840 (2006 = 1,248; 2016 = 592) eligible for propensity score matching comparison. In general, more working hours per week and working days on weekends were associated with an increased effort/reward imbalance and higher burnout scores. From 2006 to 2016, reductions in working hours per week and days worked on weekends were accompanied by improvements in occupational stress (Effort-Reward-Imbalance) and by trend in mental health indices (burnout) after matching for differences in working conditions. Conclusions: The study presents the changes concerning occupational stress factors and mental wellbeing in physicians working in intensive care in 2016 as compared to 2006. These findings may promote the implementation of preventive strategies in the vocational context to protect health and productivity of physicians, especially intensive care physicians.