Monitoring of FLT3 Phosphorylation and FLT3 Ligand Levels in Patients with FLT3-ITD Mutated Acute Myeloid Leukemia (AML) Treated with Midostaurin within the AMLSG 16-10 Trial of the German-Austrian Study Group

Abstract Background: Target inhibition of FLT3 by therapy with the recently FDA- and EMA-approved multi-targeted tyrosine kinase inhibitor (TKI) midostaurin can be monitored by plasma inhibitor activity (PIA) analysis by visualizing the level of target-dephosphorylation as previously described. When combining intensive chemotherapy with midostaurin, we have recently shown that the TKI achieves the lowest level of FLT3 phosphorylation (p-FLT3) at the end of the 1st induction cycle, indicating a deep target inhibition. However, sufficient inhibition could not be maintained during subsequent cycles by midostaurin in combination with chemotherapy, but it was reestablished during maintenance the…

Monitoring of Minimal Residual Disease (MRD) of DNMT3A Mutations (DNMT3Amut) in Acute Myeloid Leukemia (AML): A Study of the AML Study Group (AMLSG)

![Graphic][1] Background : The DNA methyltransferase 3A ( DNMT3A) is one of the most frequent mutated genes in AML with a hot spot mutation at codon R882 in 80% of the DNMT3A mut cases. In most of the studies DNMT3A mut predicts for poor overall (OS) and relapse-free survival (RFS). Recently, DNMT3A mut have been associated with age-related clonal hematopoiesis, and they have been identified in early preleukemic stem cells. These findings suggest that DNMT3A mut represents an early event in leukemogenesis and may be part of the leukemia founder clone in most AMLs harboring a DNMT3A mut. We thought to address the question whether MRD monitoring in DNMT3A mut patients (pts) can be used for pr…

Immunoselection in vivo: independent loss of MHC class I and melanocyte differentiation antigen expression in metastatic melanoma

Peptides derived from melanocyte differentiation antigens have been identified as targets for MHC class I-restricted cytolytic T lymphocytes (CTLs) in human melanoma Regression of antigen-expressing tumors as well as selection of antigen-loss variants in the presence of antigen-specific CTLs have previously been reported. In the present study, we determined the expression of the melanocyte differentiation antigens Melan A/MART-1 and tyrosinase by mRNA analysis and by immunohistochemical staining with the monoclonal antibodies (MAbs) A103 and T311. Co-expression of Melan A/MART-1 and tyrosinase was detected by both methods in 18/20 melanomas tested. However, immunohistochemistry provided add…

Measurable Residual Disease (MRD) Monitoring in Acute Myeloid Leukemia (AML) with t(8;21)(q22;q22.1) RUNX1-RUNX1T1 Identifies Patients at High Risk of Relapse: Results of the AML Study Group (AMLSG)

Background: Acute myeloid leukemia (AML) with t(8;21)(q22;q22.1) resulting in the RUNX1-RUNX1T1 gene fusion is considered favorable in the 2017 genetic risk stratification by the European LeukemiaNet (ELN). After intensive chemotherapy most patients (pts) achieve complete remission (CR), but relapse occurs in about 50% and is associated with poor prognosis. In this AML subgroup monitoring of measurable residual disease (MRD) has been shown to identify pts at higher risk of relapse. Aims: To assess the prognostic impact of MRD monitoring in bone marrow (BM) and peripheral blood (PB) in a large cohort of 155 clinically well-annotated t(8;21)-AML pts enrolled in one of six AMLSG treatment tria…

Impact Of The Pretreatment Characteristics As Well As Cyto- and Molecular-Genetic Profile On Outcome After Relapse In Acute Myeloid Leukemia

Abstract Background Cyto- and molecular-genetic abnormalities evaluated at initial diagnosis are the most powerful prognostic and in part also predictive markers in acute myeloid leukemia (AML) with regard to achievement of complete remission (CR) and survival. Nonetheless, after relapse the prognostic impact of clinical characteristics and genetic abnormalities assessed at initial diagnosis with respect to achievement of subsequent CR and survival are less clear. Aims To evaluate the probability of CR achievement and survival in relapsed AML patients in correlation to clinical characteristics and genetic abnormalities assessed at initial diagnosis as well as treatment strategy. Methods The…

Minimal Residual Disease Monitoring in Acute Myeloid Leukemia (AML) with Translocation t(8;21)(q22;q22): Results of the AML Study Group (AMLSG)

Abstract Background: Acute myeloid leukemia (AML) with t(8;21)(q22;q22) results in the formation of the RUNX1-RUNX1T1 fusion transcript which can be used to monitor minimal residual disease (MRD) by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Early identification of patients (pts) with a high risk of relapse will allow pre-emptive therapy including allogeneic hematopoietic cell transplantation (alloHCT). Recent studies in AML with NPM1 mutation or the CBFB-MYH11 gene fusion revealed that MRD persistence is significantly associated with a high risk of relapse. However, the prognostic impact of MRD assessment in RUNX1-RUNX1T1-positive AML is not well established. A…

Differential impact of allelic ratio and insertion site in FLT3-ITD-positive AML with respect to allogeneic transplantation.

The objective was to evaluate the prognostic and predictive impact of allelic ratio and insertion site (IS) of internal tandem duplications (ITDs), as well as concurrent gene mutations, with regard to postremission therapy in 323 patients with FLT3-ITD-positive acute myeloid leukemia (AML). Increasing FLT3-ITD allelic ratio (P = .004) and IS in the tyrosine kinase domain 1 (TKD1, P = .06) were associated with low complete remission (CR) rates. After postremission therapy including intensive chemotherapy (n = 121) or autologous hematopoietic stem cell transplantation (HSCT, n = 17), an allelic ratio ≥ 0.51 was associated with an unfavorable relapse-free (RFS, P = .0008) and overall survival …

RHAMM/CD168 was defined as a LAA using the approach of serological screening of expression libraries (SEREX), eliciting IgG responses in 42% of patients with AML, but not in healthy volunteers (HV) or patients with autoimmune diseases. mRNA for RHAMM was demonstrated by qRT-PCR to be expressed in leukemic blasts of more than 80% of the AML patients, but not in PBMN or CD34+ stem cells of healthy volunteers. Among normal tissues, only testis, placenta and thymus showed significant mRNA expression for the antigen, therefore sharing the expression profile of some other SEREX antigens.

Midostaurin in Combination with Intensive Induction and As Single Agent Maintenance Therapy after Consolidation Therapy with Allogeneic Hematopoietic Stem Cell Transplantation or High-Dose Cytarabine (NCT01477606)

Abstract Background: Internal tandem duplications (ITD) in the receptor tyrosine kinase FLT3 occur in roughly 25% of younger adult patients (pts) with acute myeloid leukemia (AML), implicating FLT3 as a potential target for kinase inhibitor therapy. The multi-targeted kinase inhibitor midostaurin shows potent activity against FLT3 as a single agent but also in combination with intensive chemotherapy. Aims: To evaluate the feasibility and efficacy of midostaurin in combination with intensive induction therapy and as single agent maintenance therapy after allogeneic hematopoietic stem cell transplantation (alloHSCT) or high-dose cytarabine (HIDAC). Methods: The study includes adult pts (age 1…

Generation of cytotoxic T-cell responses with synthetic melanoma-associated peptidesin vivo: Implications for tumor vaccines with melanoma-associated antigens

Peptide epitopes derived from differentiation antigens of the melanocyte lineage have been identified in human melanomas and normal cultured melanocytes as targets for MHC-restricted cytotoxic T lymphocytes (CTL). Characterization of multiple CTL-defined antigenic determinants and the presence of corresponding precursor CTL open perspectives for the development of antigen-based vaccines. In the present study, we determined the CTL reactivity against melanoma-associated peptides derived from Melan A/MART-1, tyrosinase and gp100/Pmel17 in 10 HLA-A2+ melanoma patients and 10 healthy individuals. Then, we examined the immunological effects and toxicity of intradermal inoculation of synthetic me…

Azacitidine-Containing Induction Regimens Followed by Azacitidine Maintenance Therapy in High Risk Acute Myeloid Leukemia: First Results of the Randomized Phase-II AMLSG 12-09 Study (ClinicalTrials.gov No. NCT01180322)

Abstract Abstract 412 Background: A large proportion of patients are currently not eligible for genotype-adapted strategies in acute myeloid leukemia (AML), in particular those lacking specific genetic aberrations such as PML-RARA, CBFB-MYH11, RUNX1-RUNX1T1, NPM1 or activating FLT3 mutations. This subgroup of patients accounts for about one-third of all AML patients and mainly includes the large group of AML with myelodysplasia-related changes, AML with recurrent cytogenetic abnormalities [inv(3) or t(3;3), t(9;11), t(v;11q23)] and cytogenetically normal AML (CN-AML) with wild-type NPM1 and FLT3. Prognosis in this subgroup of patients is generally poor. Azacitidine has been shown to be acti…

Impact of Donor Type on Outcome after Allogeneic Stem Cell Transplantation in Acute Myeloid Leukemia Patients: Analysis of the German-Austrian Acute Myeloid Leukemia Study Group (AMLSG)

Abstract Background:Despite recent advances in identifying novel molecular targets in AML patients, intensive chemotherapy followed by allogeneic hematopoietic stem cell transplantation (HSCT) still remains a cornerstone of AML therapy. However, outcome of HSCT depends on the availability of a donor and the donor type. Prior studies comparing HSCT from HLA-matched related donors (MRD) with matched unrelated donors (MUD), demonstrated conflicting results with regards to outcome. These conflicting results might be attributed to the genetic heterogeneity of AML. Aims:To analyze outcome with respect to donor type of 952 AML patients who received HSCT in first complete remission (CR) and were tr…

Impact of Age and Midostaurin-Dose on Response and Outcome in Acute Myeloid Leukemia with FLT3-ITD: Interim-Analyses of the AMLSG 16-10 Trial

Abstract Background: Internal tandem duplications (ITD) in the receptor tyrosine kinase FLT3 occur in roughly 25% of younger adult patients (pts) with acute myeloid leukemia (AML). The multi-targeted kinase inhibitor midostaurin combined with intensive chemotherapy has shown activity against AML with FLT3 mutations. However, toxicity and potential drug-drug interactions with strong CYP3A4 inhibitors such as posaconazole may necessitate dose reduction. Aims: To evaluate the impact of age and midostaurin dose-adaptation after intensive induction chemotherapy on response and outcome in AML with FLT3-ITD within the AMLSG 16-10 trial (NCT01477606). Methods: The study included adult pts (age 18-7…

Inverse relationship of melanocyte differentiation antigen expression in melanoma tissues and CD8+ cytotoxic-T-cell responses: evidence for immunoselection of antigen-loss variants in vivo.

Antigenic peptides derived from differentiation antigens of the melanocyte lineage were recently identified in human melanomas as targets for MHC-restricted cytotoxic T lymphocytes (CTL). CTL directed against peptides derived from the Melan A/MART-1, tyrosinase and gp100/Pmel17 antigens can be detected in melanoma patients and in healthy controls. The presence of defined antigenic peptides and corresponding precursor CTL in patients with metastatic melanoma opens perspectives for the development of antigen-specific tumor vaccines. In this study, we examined the expression of Melan A/MART-1, tyrosinase and gp100lPmel17 in fresh melanoma tissues of HLA-A2+ patients and the spontaneous CTL rea…

Midostaurin Plus Intensive Chemotherapy for Younger and Older Patients with Acute Myeloid Leukemia and FLT3 Internal Tandem Duplications

Abstract BACKGROUND: Midostaurin is a first-generation, type I multi-targeted kinase inhibitor with inhibitory activity against FLT3-ITD and -TKD mutations. Midostaurin is approved by FDA and EMA in combination with intensive induction and consolidation chemotherapy for adult patients with AML exhibiting an activating FLT3 mutation; the EMA label also includes single-agent maintenance therapy following consolidation chemotherapy. We conducted a phase-II trial (AMLSG 16-10) to evaluate midostaurin with induction chemotherapy followed by allogeneic hematopoietic-cell transplantation (HCT) and a one-year midostaurin maintenance therapy in younger and older patients with acute myeloid leukemia …

Clinical Impact of GATA2 Mutations in Acute Myeloid Leukemia Patients Harboring CEBPA Mutations: A Study of the AML Study Group (AMLSG)

Abstract Background Based on their association with certain biological and clinical features as well as their prognostic significance, mutations in the CCAAT/enhancer-binding protein-alpha (CEBPA) gene have been included as a provisional entity into the 2008 World Health Organization (WHO) classification of myeloid neoplasms. CEBPA mutations (CEBPAmut) are mainly found in acute myeloid leukemia (AML) with normal cytogenetics, and approximately 60% of the mutated patients (pts) carry biallelic mutations. Several studies showed that in particular pts with double mutant CEBPA (CEBPAdm) have a favorable outcome compared to all others. Recently, mutations in the transcription factor GATA2 were i…

The Human Leukocyte Antigen-DPB1 Degree of Compatibility Is Determined by Its Expression Level and Mismatch Permissiveness: A German Multicenter Analysis

T-cell epitope matching according to the TCE3 algorithm classifies HLA-DPB1 mismatches in permissive and non-permissive. This classification has been shown to be predictive for mortality and acute GvHD (aGvHD) events in large international cohorts. We retrospectively genotyped HLA-DPB1 in 3523 patients transplanted in Germany between 2000 and 2014 and in their unrelated donors using an Illumina amplicon-NGS based assay. Aim of the study was to evaluate DP-compatibility beyond the established TCE3 algorithm by assessing the combined effect of several DP-mismatch parameters on post-transplant outcome. We implemented an extended DP-mismatch assessment model where TCE3, DP allotype expression w…

Impact of pretreatment characteristics and salvage strategy on outcome in patients with relapsed acute myeloid leukemia

Impact of pretreatment characteristics and salvage strategy on outcome in patients with relapsed acute myeloid leukemia

Real Life Experience with ATRA-Arsenic Trioxide Based Regimen in Acute Promyelocytic Leukemia - Updated Results of the Prospective German Intergroup Napoleon Registry

Abstract Background: Standard therapy of acute promyelocytic leukemia has long relied on the combination of All-trans-retinoic acid (ATRA) and chemotherapy. The introduction of arsenic trioxide (ATO) in APL treatment has allowed achievement of similarly high remission and survival rates coupled with significantly reduced myelosuppression. Recent results of the APL0406 trial by the GIMEMA-AMLSG-SAL study groups showed that the combination of ATRA and arsenic trioxide (ATO) is superior to standard ATRA and chemotherapy (CHT) in front-line therapy of low/intermediate risk acute promyelocytic leukemia (APL). The implications of these results for the clinical practice of APL patients in Germany …

Prognostic Impact of Mutant to Wild-Type Ratio and Insertion Site in Acute Myeloid Leukemia with FLT3 Internal Tandem Duplication

Abstract Abstract 785 Background: FLT3 internal tandem duplications (FLT3-ITD) occur in about 25% of acute myeloid leukemia (AML), are associated with cooperating gene mutations (NPM1, DNMT3A), and confer an adverse prognosis. Several studies have indicated that the unfavorable impact of FLT3-ITD is influenced by a number of factors, such as the mutant to wild-type ratio (allelic ratio), insertion site of FLT3-ITD in the beta1 sheet of the tyrosine kinase domain 1, and the molecular background of cooperating mutations. Aims: To evaluate the relative impact of FLT3-ITD allelic ratio and insertion site, as well as cooperating genetic lesions on prognosis and treatment decision making in a lar…

Cytolytic T cell reactivity against melanoma-associated differentiation antigens in peripheral blood of melanoma patients and healthy individuals

Antigenic peptides derived from several differentiation antigens of the melanocyte lineage were recently identified in human melanomas as targets for HLA-A2.1-restricted cytotoxic T lymphocytes (CTLs). To examine their potential role in tumour-directed immune responses in vivo, we determined CTL reactivity against seven antigenic peptides derived from the Melan A/MART-1, tyrosinase and gp100/Pmel17 antigens in the peripheral blood of 10 HLA-A2+ healthy controls and 26 HLA-A2+ melanoma patients. The influenza matrix peptide (GILGFVFTL) presented by HLA-A2.1 was used as a control peptide. CTL reactivity was assessed in a mixed lymphocyte 'peptide' culture assay. Reactivity against Melan A/MAR…

Molecular Characterization of Relapsed Core-Binding Factor (CBF) Acute Myeloid Leukemia (AML)

Abstract Background: CBF-AML is defined by recurrent genetic abnormalities which encompass t(8;21)(q22;q22), inv(16)(p13.1q22) or less frequently t(16;16)(p13.1;q22). Most frequent secondary chromosome aberrations in t(8;21) AML are del(9q) or loss of a sex chromosome, and in inv(16)/t(16;16) AML trisomy 22 or trisomy 8. At the molecular level mutations involving KIT, FLT3, or NRAS were identified as recurrent lesions in CBF-AML. However, the underlying genetic alterations which might trigger relapse in CBF-AML are not well delineated. Thus, the aim of our study was to characterize the clonal architecture of relapsed CBF-AML. Methods: We performed mutational profiling (KIT, FLT3-ITD, FLT3-T…

Prognosis of patients with primary central nervous system lymphoma after high-dose chemotherapy followed by autologous stem cell transplantation

High-dose chemotherapy followed by autologous stem cell transplantation has been shown to be feasible and highly effective in newly diagnosed primary central nervous system lymphoma. In this retrospective multicenter study, we investigated prognosis and baseline risk factors in patients with primary central nervous system lymphoma who underwent this treatment approach. We retrospectively analyzed 105 immunocompetent patients with primary central nervous system lymphoma who underwent high-dose chemotherapy followed by autologous stem cell transplantation with or without whole brain radiotherapy as first-line consolidation treated at 12 German centers between 1997 and 2011. We estimated survi…

Treatment Results In Acute Myeloid Leukemia Over a Time Period Of 20 Years: Analysis Of The German-Austrian Acute Myeloid Leukemia Study Group (AMLSG)

Abstract Background Overall survival (OS) in acute myeloid leukemia (AML) treated with intensive chemotherapy has improved over the last 20 year especially in younger adults (18-60 years) but still remains poor in older patients (>60 years) (Döhner et al. Blood 2010). The German-Austrian AMLSG performed controlled prospective treatment trials since 1993 starting with a risk-adapted approach (phase I, 1993-1997), followed by randomized and risk-adapted treatment strategies based on cytogenetic risk groups (phase II, 1997-2002); since 2003 addition of differentiating agents and HiDAC inhibitors to intensive induction therapy was evaluated (phase III, 2003-2007). Of note, until 2007 younger…

Granulocyte-macrophage-colony-stimulating factor enhances immune responses to melanoma-associated peptides in vivo.

Peptide epitopes derived from differentiation antigens of the melanocyte lineage were recently identified in human melanomas as targets for MHC-restricted cytotoxic T lymphocytes (CTL). The characterization of multiple CTL-defined antigenic determinants has opened possibilities of development of antigen-targeted vaccines. In the present study, we determined CTL reactivity against melanoma-associated peptides derived from Melan A/MART-1, tyrosinase, and gp100/Pmel17 in 3 HLA-A2+ melanoma patients. Then, we assessed the immune responses to synthetic melanoma-associated peptides injected intradermally. After 3 cycles of immunization with peptide alone, we used systemic GM-CSF as an adjuvant du…

Donor Genetic Determinant of Thymopoiesis rs2204985 Impacts Clinical Outcome after Single HLA Mismatched HSCT

Abstract Introduction: A common genetic variant within the TCRA-TCRD locus has been recently identified as a predictive factor of thymic function and T cell repertoire diversity (Clave et al., 2018). Specifically it was shown in a mouse model that transplantation of rs2204985 AA human hematopoietic stem cells (HSC) into immunodeficient mice led to lower thymocyte counts and poorer TCR diversity. T cell mediated pathways are known to play a significant role in immunological processes affecting HSCT outcome like GvL, GvH and infection. Aim of this study was to investigate the potential impact of donor rs2204985 genotype on patient's outcome after unrelated HSCT. Methods: The study included 2,…

Pharmacodynamic Monitoring of the Efficacy of a Targeted Therapy with Midostaurin By Plasma Inhibitor Activity (PIA) Analysis in FLT3 -ITD Positive AML Patients within the AMLSG 16-10 Trial: A Study of the AML Study Group (AMLSG)

Abstract Background: Activating mutations in receptor tyrosine kinases like FLT3 (FLT3mut) lead to an aberrant signal transduction thereby causing an increased proliferation of hematopoietic cells. Internal tandem duplications (FLT3-ITD) or mutations in the tyrosine kinase domain (FLT3-TKD) occur in about 25% of younger adult patients (pts) with acute myeloid leukemia (AML), with FLT3 -ITD being associated with an unfavourable outcome. FLT3mut present an excellent target for small molecule tyrosine kinase inhibitors (TKI). The multi-targeted kinase inhibitor midostaurin (PKC412) is currently under investigation as a FLT3-inhibitor in combination with intensive chemotherapy. Monitoring of th…

Matching for the MICA-129 polymorphism is beneficial in unrelated hematopoietic stem cell transplantation.

Major histocompatibility complex class I polypeptide-related sequence A (MICA) is a highly polymorphic ligand of the activating NKG2D receptor on natural killer (NK) cells, γδ-T cells, and NKT cells. MICA incompatibilities have been associated with an increased graft-versus-host disease (GVHD) incidence, and the MICA-129 (met/val) dimorphism has been shown to influence NKG2D signaling in unrelated hematopoietic stem cell transplantation (uHSCT). We investigated the effect of MICA matching on survival after uHSCT. We sequenced 2172 patients and their respective donors for MICA. All patients and donors were high-resolution HLA-typed and matched for 10/10 (n = 1379), 9/10 (n = 636), or 8/10 (n…

Clinical impact of GATA2 mutations in acute myeloid leukemia patients harboring CEBPA mutations: a study of the AML study group.

Clinical impact of GATA2 mutations in acute myeloid leukemia patients harboring CEBPA mutations: a study of the AML study group

Predominance of Th1-type T cells in synovial fluid of patients with Yersinia-induced reactive arthritis

The pathogenetic mechanisms underlying the development of reactive arthritis and the functional capacities of synovial T cells specific for Yersinia enterocolitica are still unclear. In this study we have determined the cytokine secretion patterns of 24 CD4+ synovial fluid (SF)-derived T cell clones from 2 patients with Yersinia-induced reactive arthritis, 16 clones specific for different Yersinia antigens and 8 clones as controls. The clones specific for Yersinia antigens predominantly belong to the T helper cell 1 (Th1) subset with production of interferon (IFN)-gamma and interleukin (IL)-2, but no IL-4, whereas SF T cells not reactive with Yersinia antigens produce IL-2, IL-4 and IFN-gam…