Gilteritinib with or without venetoclax for relapsed/refractory FLT3-mutated acute myeloid leukaemia.

Patients with FLT3-mutated acute myeloid leukaemia (AML) that relapse or are refractory (R/R) to intensive induction have poor outcomes. Gilteritinib has recently become standard-of-care for patients with R/R FLT3-mutated AML. We investigated whether adding venetoclax to gilteritinib (gilt-ven) improves outcomes as compared with gilteritinib monotherapy. We included patients treated with gilteritinib (n = 19) and gilt-ven (n = 17) for R/R AML after intensive chemotherapy. Gilteritinib and gilt-ven groups did not differ in terms of mCRc rates (53% and 65%, p = 0.51) and realization of allogeneic haematopoietic stem-cell transplantation (HSCT, 47% and 35%, p = 0.5). Overall survival (OS) was comparable between groups, although a trend towards better OS was seen with gilt-ven (12-month OS 58.8% [95% CI 39.5%-87.6%]) versus gilteritinib (42.1% [95% CI 24.9%-71.3%] for gilteritinib). Early salvage with gilt-ven versus any other gilteritinib-based approach was associated with the best outcome (p = 0.031). Combination therapy was associated with increased haematological toxicity. In summary, gilt-ven did not improve remissions or HSCT-realization rates in patients with R/R FLT3-mutated AML as compared with gilteritinib and was associated with increased haematological toxicity. Although OS did not differ, a trend towards better survival was suggested with gilt-ven and a survival benefit was shown for gilt-ven approach when sequenced early for salvage.

ETV6-NCOA2 fusion induces T/myeloid mixed-phenotype leukemia through transformation of nonthymic hematopoietic progenitor cells.

Mixed-phenotype acute leukemia is a rare subtype of leukemia in which both myeloid and lymphoid markers are co-expressed on the same malignant cells. The pathogenesis is largely unknown, and the treatment is challenging. We previously reported the specific association of the recurrent t(8;12)(q13;p13) chromosomal translocation that creates the ETV6-NCOA2 fusion with T/myeloid leukemias. Here we report that ETV6-NCOA2 initiates T/myeloid leukemia in preclinical models; ectopic expression of ETV6-NCOA2 in mouse bone marrow hematopoietic progenitors induced T/myeloid lymphoma accompanied by spontaneous Notch1-activating mutations. Similarly, cotransduction of human cord blood CD34+ progenitors with ETV6-NCOA2 and a nontransforming NOTCH1 mutant induced T/myeloid leukemia in immunodeficient mice; the immunophenotype and gene expression pattern were similar to those of patient-derived ETV6-NCOA2 leukemias. Mechanistically, we show that ETV6-NCOA2 forms a transcriptional complex with ETV6 and the histone acetyltransferase p300, leading to derepression of ETV6 target genes. The expression of ETV6-NCOA2 in human and mouse nonthymic hematopoietic progenitor cells induces transcriptional dysregulation, which activates a lymphoid program while failing to repress the expression of myeloid genes such as CSF1 and MEF2C. The ETV6-NCOA2 induced arrest at an early immature T-cell developmental stage. The additional acquisition of activating NOTCH1 mutations transforms the early immature ETV6-NCOA2 cells into T/myeloid leukemias. Here, we describe the first preclinical model to depict the initiation of T/myeloid leukemia by a specific somatic genetic aberration.

Cellular and metabolic characteristics of pre-leukemic hematopoietic progenitors with GATA2 haploinsufficiency.

Mono-allelic germline disruptions of the transcription factor GATA2 result in a propensity for developing myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), affecting more than 85% of carriers. How a partial loss of GATA2 functionality enables leukemic transformation years later is unclear. This question has remained unsolved mainly due to the lack of informative models, as Gata2 heterozygote mice do not develop hematologic malignancies. Here we show that two different germline Gata2 mutations (TgErg/Gata2het and TgErg/Gata2L359V) accelerate AML in mice expressing the human hematopoietic stem cell regulator ERG. Analysis of Erg/Gata2het fetal liver and bone marrow-derived hematopoietic cells revealed a distinct pre-leukemic phenotype. This was characterized by enhanced transition from stem to progenitor state, increased proliferation, and a striking mitochondrial phenotype, consisting of highly expressed oxidative-phosphorylation-related gene sets, elevated oxygen consumption rates, and notably, markedly distorted mitochondrial morphology. Importantly, the same mitochondrial gene-expression signature was observed in human AML harboring GATA2 aberrations. Similar to the observations in mice, non-leukemic bone marrows from children with germline GATA2 mutation demonstrated marked mitochondrial abnormalities. Thus, we observed the tumor suppressive effects of GATA2 in two germline Gata2 genetic mouse models. As oncogenic mutations often accumulate with age, GATA2 deficiency-mediated priming of hematopoietic cells for oncogenic transformation may explain the earlier occurrence of MDS/AML in patients with GATA2 germline mutation. The mitochondrial phenotype is a potential therapeutic opportunity for the prevention of leukemic transformation in these patients.

A Longitudinal Assessment of the Natural Change in Haemoglobin, Haematocrit, and Mean Corpuscular Volume with Age.

INTRODUCTION: We aimed to assess the natural annual trends in the levels of haemoglobin, haematocrit, and mean corpuscular volume (MCV) in a population of adults, together with the influence of different clinical parameters on these trends. METHODS: A retrospective analysis was carried out on data from a large cohort of subjects attending a screening centre in Israel. For each subject, the yearly average change of haemoglobin, haematocrit, and MCV was calculated. Statistical analysis was performed for the whole cohort and for different subgroups. RESULTS: The study included 3,551 subjects. The average annual rates of decline were found to be -0.0550 g/dL (95% confidence interval [CI] -0.0590 g/dL to -0.0503 g/dL) and -0.097% (95% CI -0.112% to -0.083%) for haemoglobin and haematocrit, respectively. An average annual increase in the MCV level by 0.184 fL (95% CI 0.168 fL-0.200 fL) was found. Among men, the rate of decline in haemoglobin was found to be twice as high compared with women -0.06 g/dL versus -0.03 g/dL, respectively (p = 0.0063). In a multivariate analysis, gender remained the only parameter significantly associated with the annual decline of haemoglobin (p = 0.0001). CONCLUSION: An annual average decrease in the levels of haemoglobin and haematocrit together with an annual increase in MCV was found. These changes were more prominent in men.

Gilteritinib monotherapy for relapsed/refractory FLT3 mutated acute myeloid leukemia: a real-world, multi-center, matched analysis.

Patients with FLT3-mutated relapsed or refractory (R/R) acute myeloid leukemia (AML) have a dismal prognosis. Gilteritinib is a FLT3 tyrosine kinase inhibitor (TKI) recently approved for patients with R/R AML. We aimed to characterize real-world data regarding gilteritinib treatment in FLT3-mutated R/R AML and to compare outcomes with matched FLT3-mutated R/R AML patients treated with chemotherapy-based salvage regimens. Twenty-five patients from six academic centers were treated with gilteritinib for FLT3-mutated R/R AML. Eighty percent were treated with a prior intensive induction regimen and 40% of them received prior TKI therapy. Twelve patients (48%) achieved complete response (CR) with gilteritinib. The estimated median overall survival (OS) of the entire cohort was eight (CI 95% 0-16.2) months and was significantly higher in patients who achieved CR compared to those who did not (16.3 months, CI 95% 0-36.2 vs. 2.6 months, CI 95% 1.47-3.7; p value = 0.046). In a multivariate cox regression analysis, achievement of CR was the only predictor for longer OS (HR 0.33 95% CI 0.11-0.97, p = 0.044). Prior TKI exposure did not affect OS but was associated with better event-free survival (HR 0.15 95% CI 0.03-0.71, p = 0.016). An age and ELN-risk matched comparison between patients treated with gilteritinib and intensive salvage revealed similar response rates (50% in both groups); median OS was 9.6 months (CI 95% 2.3-16.8) vs. 7 months (CI 95% 5.1-8.9) in gilteritinib and matched controls, respectively (p = 0.869). In conclusion, in the real-world setting, gilteritinib is effective, including in heavily pre-treated, TKI exposed patients.

T-Lymphoblastic Leukemia/Lymphoma and Thymoma: A Case Report and Review of the Literature of a Rare Association.

The co-occurrence of thymoma and T-lymphoblastic lymphoma/leukemia is an extremely rare but previously reported association that poses a diagnostic and therapeutic challenge. We describe a 67-year-old patient with long-standing untreated B1 thymoma that presented with constitutional symptoms and a painless soft tissue mass on the right chest wall. Pathological analysis of the biopsy from the mass demonstrated T-lymphoblastic leukemia/lymphoma. The patient went through a complicated course, was refractory to several lines of therapy, and eventually underwent allogeneic hematopoietic stem cell transplantation in complete remission from a matched related donor. The association between thymoma and malignant neoplasms has been described in the literature, most notably with colorectal adenocarcinoma and thyroid cancer. Thymoma-associated leukemia is, however, extremely unusual, with limited reports in the literature. Distinguishing between thymoma and leukemia can be challenging and often requires meticulous diagnostic efforts. For patients with a past history of thymoma, awareness of this particular association should be bared in mind to allow earlier diagnosis and therapy.

Chromatin occupancy and epigenetic analysis reveal new insights into the function of the GATA1 N terminus in erythropoiesis.

Mutations in GATA1, which lead to expression of the GATA1s isoform that lacks the GATA1 N terminus, are seen in patients with Diamond-Blackfan anemia (DBA). In our efforts to better understand the connection between GATA1s and DBA, we comprehensively studied erythropoiesis in Gata1s mice. Defects in yolks sac and fetal liver hematopoiesis included impaired terminal maturation and reduced numbers of erythroid progenitors. RNA-sequencing revealed that both erythroid and megakaryocytic gene expression patterns were altered by the loss of the N terminus, including aberrant upregulation of Gata2 and Runx1. Dysregulation of global H3K27 methylation was found in the erythroid progenitors upon loss of N terminus of GATA1. Chromatin-binding assays revealed that, despite similar occupancy of GATA1 and GATA1s, there was a striking reduction of H3K27me3 at regulatory elements of the Gata2 and Runx1 genes. Consistent with the observation that overexpression of GATA2 has been reported to impair erythropoiesis, we found that haploinsufficiency of Gata2 rescued the erythroid defects of Gata1s fetuses. Together, our integrated genomic analysis of transcriptomic and epigenetic signatures reveals that, Gata1 mice provide novel insights into the role of the N terminus of GATA1 in transcriptional regulation and red blood cell maturation which may potentially be useful for DBA patients.

Subcutaneous versus intravenous granulocyte colony stimulating factor for the treatment of neutropenia in hospitalized hemato-oncological patients: randomized controlled trial.

Intravenous (IV) granulocyte colony stimulating factor (G-CSF) might be safer and more convenient than subcutaneous (SC) administration to hospitalized hemato-oncological patients receiving chemotherapy. To compare IV vs. SC G-CSF administration, we conducted a randomized, open-label trial. We included inpatients receiving chemotherapy for acute myeloid leukemia, acute lymphoblastic leukemia, lymphoma or multiple myeloma, and allogeneic or autologous hematopoietic cell transplantation (HCT). Patients were randomized to 5 mcg/kg single daily dose of IV bolus versus SC filgrastim given for its clinical indications. Patients were crossed-over to the alternate study arm on the subsequent chemotherapy course. The primary outcomes were time from initiation of filgrastim to recovery of stable neutrophil count of >500 cells/µL and a composite clinical outcome of infection or death assessed for the first course post-randomization. The study was stopped on the second interim analysis. Of 120 patients randomized, 118 were evaluated in the first treatment course. The mean time to neutropenia resolution was longer with IV G-CSF [7.9 days, 95% confidence interval (CI) 6.6-9.1] compared with SC G-CSF (5.4 days, 95% CI 4.6-6.2), log-rank P = 0.001. Longer neutropenia duration was observed in all patient subgroups, except for patients undergoing autologous HCT. There was no significant difference between groups in the occurrence of infection or death, but more deaths were observed with IV (4/57, 7%) versus SC (1/61, 1.6%) G-CSF administration, P = 0.196. Similar results were observed when all 158 courses following cross-over were analyzed. Patients reported similar pain and satisfaction scores in both groups. Bolus IV administration of G-CSF results in longer neutropenia duration than SC administration, with no difference in clinical or quality-of-life measures.

Incidence and Clinical Presentation of Severe Neurotoxicity from Nelarabine in Patients with T-Cell Acute Lymphoblastic Leukemia.

BACKGROUND: Nelarabine is a purine analog with demonstrated efficacy in the treatment of T-cell Lymphoblastic Leukemia and Lymphoma (T-ALL/LBL). Despite its efficacy and excellent blood-brain barrier penetration, it has a significant side effect profile which is namely concerning for neurotoxicity. Reported neurotoxicity has varied from mild peripheral neuropathy to debilitating grade 4 neurologic complications including Guillain-Barre like syndrome and myelopathy. PATIENTS AND METHODS: We conducted a single centered, retrospective case series to study patients who developed severe neurotoxicity after receiving nelarabine as part of T-ALL treatment. One hundred thirty-five patients were identified. Thirteen patients were reviewed for severe neurotoxicity (defined as ≥grade 3), and of those five patients were deemed to have neurotoxicity secondary to nelarabine exposure. RESULTS: Five patients (4%) developed severe neurotoxicity as manifested by Guillain-Barre like syndrome or myelopathy within a timeframe of eight to fifty-eight days from last nelarabine dose. Upon diagnosis, patients received formal neurologic evaluation by our neuro-oncology specialists including imaging, cerebrospinal fluid testing, and electromyography. Patients were treated with IVIG, and steroids upon diagnosis, but the majority of neuro-deficits were irreversible. CONCLUSION: Our study shows that nelarabine is generally well-tolerated, and the incidence of severe neurotoxicity is rare. Given the potential risk of severe neurotoxicity, we propose capped dose of nelarabine 1000 mg/day, neurological assessment before subsequent dosing, and avoidance of simultaneous IT therapy during nelarabine administration.

The NCOR-HDAC3 co-repressive complex modulates the leukemogenic potential of the transcription factor ERG.

The ERG (ETS-related gene) transcription factor is linked to various types of cancer, including leukemia. However, the specific ERG domains and co-factors contributing to leukemogenesis are poorly understood. Drug targeting a transcription factor such as ERG is challenging. Our study reveals the critical role of a conserved amino acid, proline, at position 199, located at the 3' end of the PNT (pointed) domain, in ERG's ability to induce leukemia. P199 is necessary for ERG to promote self-renewal, prevent myeloid differentiation in hematopoietic progenitor cells, and initiate leukemia in mouse models. Here we show that P199 facilitates ERG's interaction with the NCoR-HDAC3 co-repressor complex. Inhibiting HDAC3 reduces the growth of ERG-dependent leukemic and prostate cancer cells, indicating that the interaction between ERG and the NCoR-HDAC3 co-repressor complex is crucial for its oncogenic activity. Thus, targeting this interaction may offer a potential therapeutic intervention.

A novel method for detecting the cellular stemness state in normal and leukemic human hematopoietic cells can predict disease outcome and drug sensitivity.

Acute leukemia is an aggressive blood malignancy with low survival rates. A high expression of stem-like programs in leukemias predicts poor prognosis and is assumed to act in an aberrant fashion in the phenotypically heterogeneous leukemia stem cell (LSC) population. A lack of suitable genome engineering tools that can isolate LSCs based on their stemness precludes their comprehensive examination and full characterization. We hypothesized that tagging endogenous stemness-regulatory regions could generate a genome reporter for the putative leukemia stemness-state. Our analysis revealed that the ERG + 85 enhancer region can serve as a marker for stemness-state and a fluorescent lentiviral reporter was developed that can accurately recapitulate the endogenous activity. Using our novel reporter, we revealed cellular heterogeneity in several leukemia cell lines and patient-derived samples. Alterations in reporter activity were associated with transcriptomic and functional changes that were closely related to the hematopoietic stem cell (HSC) identity. Notably, the differentiation potential was skewed towards the erythro-megakaryocytic lineage. Moreover, an ERG + 85High fraction of AML cells could regenerate the original cellular heterogeneity and was enriched for LSCs. RNA-seq analysis coupled with in silico drug-screen analysis identified 4HPR as an effective inhibitor of ERG + 85High leukemia growth. We propose that further utilization of our novel molecular tool will identify crucial determinants of LSCs, thus providing a rationale for their therapeutic targeting.

An ERG Enhancer-Based Reporter Identifies Leukemia Cells with Elevated Leukemogenic Potential Driven by ERG-USP9X Feed-Forward Regulation.

Acute leukemia is a rapidly progressing blood cancer with low survival rates. Unfavorable prognosis is attributed to insufficiently characterized subpopulations of leukemia stem cells (LSC) that drive chemoresistance and leukemia relapse. Here we utilized a genetic reporter that assesses stemness to enrich and functionally characterize LSCs. We observed heterogeneous activity of the ERG+85 enhancer-based fluorescent reporter in human leukemias. Cells with high reporter activity (tagBFPHigh) exhibited elevated expression of stemness and chemoresistance genes and demonstrated increased clonogenicity and resistance to chemo- and radiotherapy as compared with their tagBFPNeg counterparts. The tagBFPHigh fraction was capable of regenerating the original cellular heterogeneity and demonstrated increased invasive ability. Moreover, the tagBFPHigh fraction was enriched for leukemia-initiating cells in a xenograft assay. We identified the ubiquitin hydrolase USP9X as a novel ERG transcriptional target that sustains ERG+85-positive cells by controlling ERG ubiquitination. Therapeutic targeting of USP9X led to preferential inhibition of the ERG-dependent leukemias. Collectively, these results characterize human leukemia cell functional heterogeneity and suggest that targeting ERG via USP9X inhibition may be a potential treatment strategy in patients with leukemia. SIGNIFICANCE: This study couples a novel experimental tool with state-of-the-art approaches to delineate molecular mechanisms underlying stem cell-related characteristics in leukemia cells.

The association of central venous catheter placement timing with infection rates in patients with acute leukemia.

BACKGROUND: Timing of central venous catheter (CVC) insertion among patients with acute leukemia is debatable. Early insertion increases convenience, but might increase infection rates. METHODS: We assessed retrospectively the rate of central line-associated bloodstream infections (CLABSI) according to CVC time of insertion in patients with acute leukemia admitted for induction or salvage therapy. The study was conducted in the Hematology Department of a Tertiary hospital in Israel between 2007 and 2011. Early CVC placement was defined as CVC inserted during the first week of induction therapy. CLABSI rate was documented between the seventh day of induction therapy to 30 days after its completion. RESULTS: A total of 127 patients were included. Acute myeloid leukemia was the most common diagnosis (103 patients, 80.5%). Late CVC placement was associated with CLABSI after adjustment to the Charlson comorbidity index (OR 3.4, 95% CI 1.1-10.45), p=0.03. CONCLUSION: Delaying CVC placement in adult patients with acute leukemia may be associated with higher rate of CLABSI in the early period after induction therapy.

C reactive protein and long-term risk for chronic kidney disease: a historical prospective study.

INTRODUCTION: C reactive protein (CRP) is an acute phase reactant that primarily produced by hepatocytes yet may be locally expressed in renal tubular cells. We assessed the association of CRP and the risk for chronic kidney disease (CKD) development. METHODS: Historical prospective cohort study was conducted on subjects attending a screening center in Israel since the year 2000. Subjects with an estimated GFR (eGFR) above 60 ml/min/1.73 m(2) at baseline were included, and high sensitive (hs) CRP levels as well as eGFR were recorded for each visit. Follow up continued for at least 5 years for each subject until 2013. Risk for CKD at end of follow up was assessed in relation to mean hs-CRP levels of each subject. The confounding effects of other predictors of CKD were examined. A logistic regression model treating CRP as a continuous variable was further applied. RESULTS: Out of 4,345 patients, 42 (1%) developed CKD in a mean follow up of 7.6 ± 2 years. Elevated levels of CRP were associated with greater risk for CKD (crude OR 4.17, 95% CI 1.46-11.89). The OR for the association of CRP with CKD when controlling for age and gender was 5.2 (95% CI 1.7-16.2). When controlling for established renal risk factors, elevated CRP levels remained significantly associated with greater risk for CKD (OR 5.42, 95% CI 1.76-16.68). When applying logistic regression models treating CRP as a continuous variable, for patients with diabetes mellitus (DM), hypertension (HTN) or eGFR between 60-90 ml\min\1.73 m(2), the predictive role of CRP for CKD was highly significant. CONCLUSION: Elevated CRP level is an independent risk factor for CKD development. In patients with DM, HTN or baseline eGFR between 60-90 ml\min\1.73 m(2) its predictive role is enhanced.

Tumor lysis syndrome and malignant melanoma.

Tumor lysis syndrome (TLS) is an oncological emergency that results from massive cytolysis of malignant cells with a sudden release of their contents into the systemic circulation. TLS was rarely described in patients with malignant melanoma. In this article, we describe two patients with malignant melanoma who developed this syndrome. In one of them, the syndrome occurred spontaneously, and this is the second description of spontaneous tumor lysis in a patient with melanoma. We reviewed the previous patients with melanoma-induced TLS and discussed the manifestations and the pathophysiology of the syndrome in our patients.

The safety of a trial of labor after cesarean section in a grandmultiparous population.

BACKGROUND: The rate of vaginal birth after a cesarean (VBAC) delivery in the multiparous population has decreased largely in recent years because of maternal and neonatal complications. The clinical management of grand multiparous (GMP) women (>5 births) with a prior cesarean delivery is even less clear. The purpose of the present study was to assess the risks of maternal and neonatal complications associated with VBAC compared to that of repeated elective cesarean section (CS) in the GMP population. METHODS: A retrospective study of 1,102 GMP women with a singleton gestation and a prior single CS was conducted. Data were retrieved from the database of the Department of Obstetrics and Gynecology at the Soroka University Medical Center, Beer Sheva, Israel. Maternal and neonatal outcomes were compared between women who underwent a successful VBAC attempt, women who had failed in a trial of labor and women who had an elective repeated CS. RESULTS: Six hundred and nineteen women (56%) underwent a successful VBAC, 155 (14%) underwent a trail of labor and 328 (30%) had an elective repeated CS. Women who had a successful VBAC required less blood transfusion, and had less puerperal fever diseases (P < 0.001). Induction or augmentation of labor was associated with failure of VBAC (P < 0.001). No significant differences in neonatal complications were observed between the groups. No significant difference in uterine dehiscence, uterine rupture, amnionitis, postpartum hemorrhage, hysterectomy, puerperal fever and thromboembolic diseases was observed between the groups. CONCLUSIONS: A successful VBAC in the GMP population was not associated with a higher risk of maternal complications in comparison with a repeated elective CS.