Hyperdiploid Karyotype Research Articles

Occurrence of high hyperdiploid karyotypes in childhood Acute Lymphoblastic Leukemia

Abstract Introduction/Objective High hyperdiploidy is defined as the non-random gain of chromosomes, increasing the modal chromosome number from 46 to between 51 and 65 or 67. This condition is the most common finding in childhood acute lymphoblastic leukemia, with a good outcome. It is generally characterized by the gain of chromosomes, typically X, 4, 6, 10, 14, 17, 18, and 21. The objective of this study is to determine the frequency of high hyperdiploidy in childhood ALL. Methods/Case Report Cytogenetic results of 435 patients, reported between October 2020 and September 2022 were reviewed retrospectively. All individuals were suspected for ALL between ages 1-15 years. Chromosomal analysis was performed in the Cytogenetics Lab of the Indus hospital and health network. Fluorescent in-situ hybridization (FISH) analysis were also carried out with probes for co-relating the gain of chromosomes. Results (if a Case Study enter NA) A total of 435 individuals were successfully karyotyped, 82 karyotypes showed hyperploidy without any additional abnormality, 213 patients showed hyperploidy along with additional structural aberrations, and 143 individuals showed normal karyotype. Among all the hyperploid karyotypes, chromosomes X, 4, 6, 10, 14, 17, 18, 21 were all gained in approximately 70% of the cases. Whereas, chromosome 21 was gained in 100% of all cases. FISH results also showed the gain of signals for particular probes including chromosomes 8, 9, 11, 12, 21 and 22. Conclusion In summary, this study leads to the fact that high hyperdiploidy is the most common abnormality in childhood acute lymphoblastic leukemia. It is assured that the occurrence of constituent trisomies of certain chromosomes is linked with the prognosis of the disease and also helps in determining the differences in treatment of the disease. Furthermore, correlation of karyotypes with the FISH results have also played a vital role in increasing the accuracy of results in this study.

Clinical characteristics and prognosis of childhood acute lymphoblastic leukemia with CD123 expression

To investigate the expression of CD123 in children with acute lymphoblastic leukemia (ALL) and its effect on the clinical characteristics and prognosis of children with B-lineage acute lymphoblastic leukemia (B-ALL). A retrospective analysis was conducted on the clinical data of 251 children with ALL who were admitted to the Department of Hematology and Oncology, Children's Hospital of Kunming Medical University, from December 2019 to June 2022. According to the expression of CD123 at initial diagnosis, the children were divided into CD123+ group and CD123- group, and the two groups were compared in terms of clinical characteristics and treatment outcome. The factors influencing the prognosis were analyzed. Among the 251 children with ALL, there were 146 children (58.2%) in the CD123+ group. The B-ALL group had a significantly higher positive expression rate of CD123 than the acute T lymphocyte leukemia group (P<0.05). Compared with the CD123- group, the CD123+ group had significantly lower peripheral blood leukocyte count and percentage of juvenile cells and a significantly higher proportion of children with high hyperdiploid karyotype or an age of 1-10 years, with a relatively low proportion of children with E2A-PBX1 fusion gene (P<0.05). The multivariate Cox proportional-hazards regression model analysis showed that compared with the >10 years group, the 1-10 years group had a significantly higher overall survival rate (P<0.05), and compared with the high risk group, the moderate risk group had a significantly higher event-free survival rate in children with B-ALL (P<0.05). CD123 is widely expressed in children with B-ALL, and positive expression of CD123 might be an indicator for good prognosis in children with B-ALL, which is of great significance for evaluating the efficacy of remission induction therapy and survival prognosis of children with B-ALL.

High hyperdiploid karyotype with ≥ 49 chromosomes represents a heterogeneous subgroup of acute myeloid leukemia with differential TP53 mutation status and prognosis: a single-center study from China.

High hyperdiploid karyotype with ≥ 49 chromosomes (which will be referred to as HHK) is rare in acute myeloid leukemia (AML). The European leukemia network (ELN) excluded those harboring only numerical changes (with ≥ 3 chromosome gains) from CK and listed them in the intermediate risk group, while the UK National Cancer Research Institute Adult Leukaemia Working Group classification defined ≥ 4 unrelated chromosome abnormalities as the cutoff for a poorer prognosis. Controversies occurred among studies on the clinical outcome of HHK AML, and their molecular characteristics remained unstudied. We identified 1.31% (133/10,131) HHK cases within our center, among which 48 cases only had numerical changes (NUM), 42 had ELN defined adverse abnormalities (ADV) and 43 had other structural abnormalities (STR). Our study demonstrated that: (1) No statistical significance for overall survival (OS) was observed among three cytogenetic subgroups (NUM, STR and ADV) and HHK AML should be assigned to the adverse cytogenetic risk group. (2) The OS was significantly worse in HHK AML with ≥ 51 chromosomes compared with those with 49-50 chromosomes. (3) The clinical characteristics were similar between NUM and STR group compared to ADV group. The former two groups had higher white blood cell counts and blasts, lower platelet counts, and mutations associated with signaling, while the ADV group exhibited older age, higher chromosome counts, higher percentage of myelodysplastic syndrome (MDS) history, and a dominant TP53 mutation.

The biological and clinical impact of deletions before and after large chromosomal gains in multiple myeloma

AbstractAcquisition of a hyperdiploid (HY) karyotype or immunoglobulin heavy chain (IgH) translocations are considered key initiating events in multiple myeloma (MM). To explore if other genomic events can precede these events, we analyzed whole-genome sequencing data from 1173 MM samples. By integrating molecular time and structural variants within early chromosomal duplications, we indeed identified pregain deletions in 9.4% of patients with an HY karyotype without IgH translocations, challenging acquisition of an HY karyotype as the earliest somatic event. Remarkably, these deletions affected tumor suppressor genes (TSGs) and/or oncogenes in 2.4% of patients with an HY karyotype without IgH translocations, supporting their role in MM pathogenesis. Furthermore, our study points to postgain deletions as novel driver mechanisms in MM. Using multiomics approaches to investigate their biologic impact, we found associations with poor clinical outcome in newly diagnosed patients and profound effects on both the oncogene and TSG activity despite the diploid gene status. Overall, this study provides novel insights into the temporal dynamics of genomic alterations in MM.

Molecular Subtypes in BCR::ABL1-Positive ALL Are Defined By Cellular Origins and Cooperating Genomic Events

Two developmental trajectories are acknowledged in BCR::ABL1-positive acute lymphoblastic leukemia (ALL) as distinct diagnostic entities by the ICC classification: ‘lymphoid-only’ with BCR::ABL1 restricted to the leukemic B precursor compartment vs. ‘multilineage’ with BCR::ABL1 involvement also in other hematopoietic lineages. Diagnostic standards for establishing this distinction are lacking and associated biological and clinical features are insufficiently characterized. To establish developmental trajectories, biological phenotypes, and clinical impact we analyzed n=277 BCR::ABL1-positive ALL patients (age: 2-84 years, median: 46) including our GMALL reference data set (n=113) and two independent validation cohorts (MLL: n=61; St Jude's: n=103; Gu Z, et al. Nat Genet. 2019). Unsupervised gene expression analysis (RNA-Seq: n=277) identified two major gene expression clusters with two further sub-clusters each (Figure A). This clustering was confirmed by a machine learning classifier trained on the GMALL data set which achieved similar grouping of samples in the external validation cohorts. BCR:: ABL1-FISH on FACS-sorted bone marrow/peripheral blood samples revealed the presence of BCR::ABL1 in leukemic as well as myeloid cells in n=18/18 samples from the 1 st major cluster (termed 'multilineage'). In the 2 nd major cluster ('lymphoid'), BCR::ABL1 was restricted to the lymphoid lineage in n=13/16 samples (p&amp;lt;0.001), with n=3/16 cases harboring BCR::ABL1-positive myeloid cells at lower frequencies compared to the multilineage cluster. In each cluster, two patients also harbored BCR::ABL1-positive mature B cells. T cells remained BCR::ABL1-negative. Diagnostic FACS data and analysis of proximity to normal human lymphoid gene expression confirmed more frequent myeloid co-expression and higher proximity to normal pro-B cells in the multilineage cluster, whereas lymphoid cases had increased lymphoid surface marker expression and a stronger proximity to normal pre-B I cells. Genomic profiling using WGS/SNParrays (n=160) revealed significant enrichment for genomic events in the four gene expression sub-clusters: focal deletions comprising exons 1 and 2 of HBS1-like translational GTPase ( HBS1L) or monosomy 7 were strongly enriched in the two multilineage sub-clusters ('delHBS1L'; n=20/27 vs. n=3/133 in remaining cohort or 'del7'; n=16/25 vs. n=10/135; p&amp;lt;0.001). Remarkably, a novel alternative HBS1L transcript with a putative TSS in intron 3 was highly expressed in both multilineage sub-clusters but not in BCR::ABL1 negative ALL cases or healthy B lymphoid progenitors, suggesting this transcript as novel cooperating event in multilineage BCR::ABL1-positive ALL. One lymphoid sub-cluster was enriched for homozygous deletions in IKZF1 ('IKZF1'; n=11/55 vs. n=4/105; p=0.008), whereas the other was enriched for homozygous CDKN2A/B deletions (n=21/53 vs. n=3/107; p&amp;lt;0.001) and PAX5 deletions (n=33/53 vs n=26/107; p&amp;lt;0.001; 'CDKN2A/PAX5'). Hyperdiploid karyotypes were exclusive to the lymphoid main cluster, mostly in CDKN2A/PAX5. We analyzed the clinical implications of these newly established BCR::ABL1-positive ALL subtypes in our homogenously treated GMALL adult patient cohort (n=98, first diagnosis 2014-2021) including TKI treatment combined with age-adapted chemotherapy, MRD monitoring and allo-SCT in 1 st CR (n=84/98, 86%). Overall survival (OS) at 3 years was uniformly high in multilineage and lymphoid cases (70%±6% vs. 70%±8%; p=0.890; Figure B). However, analysis of the sub-clusters revealed an inferior 3-years OS for the IKZF1 -/- enriched cluster in contrast to excellent outcome in hyperdiploid cases and intermediate outcomes in the remaining sub-clusters (Figure B). These data highlight that transcriptomic signatures in BCR::ABL1-positive ALL are driven by developmental disease origins (‘lymphoid’ vs. ‘multilineage‘) and specific patterns of corresponding genomic events. Novel molecular subtypes of BCR::ABL1-positive ALL have distinct outcomes in the context of current GMALL treatment protocols. Gene-expression based subtype definitions enable classification of BCR::ABL1-positive ALL according to ICC definitions based on RNA-Seq data alone. These definitions have been implemented in ALLCatchR - our freely available tool for ALL subtype allocation - to facilitate validation and application in clinical diagnostics.

Venous Thromboembolism in Adolescents and Young Adults with Acute Lymphoblastic Leukemia Treated on a Pediatric-Inspired Regimen

Introduction Adolescent and young adult (AYA) patients (pts) with acute lymphoblastic leukemia (ALL) can be effectively treated with pediatric-inspired ALL regimens which incorporate asparaginase (ASP). Asparaginase is associated with increased venous thromboembolic (VTE) complications. We examined the incidence of and risk factors for VTE events as well as the impact of VTE events on outcomes of AYA pts treated on Dana-Farber Cancer Institute (DFCI) ALL Consortium Protocols. Methods We identified pts aged 15-50 years diagnosed with Philadelphia chromosome negative (Ph-neg) ALL treated on 4 multicenter DFCI Consortium protocols (Pediatric 00-001, Pediatric 05-001, Adult 01-175, and Adult 06-254), or treated as per these protocols between 2000-2021. All regimens included an ASP containing induction, 30 weeks of continuous ASP exposure during consolidation and a continuation phase without ASP. The use of a pegylated vs non-pegylated ASP formulation varied between protocols. As ASP exposure is associated with both VTE and survival, it may confound the association between VTE and survival; thus, to ameliorate confounding, all survival associated outcomes were conducted on pts who remained on protocol for at least 1 year (encompassing ASP exposure). Overall survival (OS) and event free survival (EFS) were presented with Kaplan Meier curves and comparisons were made by the log-rank test. Cumulative incidence of VTE, relapse (CIR) and non-relapse mortality (NRM) were estimated by the cumulative incidence method with the appropriate competing risks, and comparisons were made by the Gray test. Cox regression analysis was fit to evaluate the effect of covariates on OS and EFS. Results Among 341 Ph-neg AYA ALL pts aged 15-50 years, 109 (32%) experienced one or more VTE events. The baseline characteristics did not differ between pts who experienced a VTE and those who did not experience a VTE, except for a higher rate of VTE among overweight/obese pts (BMI≥25 kg/m 2, n=56, 38%) vs normal BMI (n=53, 27%, p=0.04) and a lower rate of VTE in patients with hyperdiploid vs non-hyperdiploid karyotype (n=4, 12% vs n=105, 34%, p&amp;lt;0.01). Of the 109 pts with VTE, 9 (8%) experienced sinus vein thrombosis (2.6% in the overall cohort) and 19 (17%) experienced at least one additional VTE. Most initial VTE events occurred during consolidation (n=78, 72%), followed by induction (n=22, 20%), and continuation/follow-up (n=9, 8%). The 2-yr cumulative incidence of VTE was 32% (95% CI, 27%-37%) and was similar between patients who were treated with non-pegylated ASP vs. pegylated ASP (n=43, 30% vs n=65, 35%, p=0.35). The 2-yr cumulative incidence of VTE was higher in the BMI ≥ 25 kg/m 2 group compared to those with normal BMI (38% vs 28%, p=0.035, Figure 1) and was the only covariate associated with increased VTE risk in the univariate regression model (HR 1.49, 95% CI, 1.03-2.17). Among pts who completed ≥ 1 year of protocol therapy (n=220), the 4-year OS was 92%, and did not differ between pts who experienced VTE vs. not (94% vs 90%, p=0.99, Figure 2). Similarly, there were no differences in 4-year CIR (14% vs 11%, p=0.50), NRM (0% vs 3%, p=0.37), and EFS (86% vs 86%, p=0.79). In univariate analysis for OS, obese BMI (&amp;gt;30 kg/m 2), higher WBC, B-cell immunophenotype, and fewer weeks on ASP therapy were associated with worse OS; all remained predictive in the multivariable model. In the uni- and multivariable analysis for EFS, higher WBC and B-cell immunophenotype were associated with worse EFS. Notably, VTE was not associated with worse OS or EFS in all regression analyses. Conclusion Among AYAs treated on DFCI ALL Consortium protocols, VTE events were frequent, occurred mostly during consolidation phase and were more common among pts with overweight/obese BMI vs normal BMI. Sinus vein thrombosis was rare. VTE incidence did not impact CIR, NRM, EFS or OS, suggesting that VTE is a manageable toxicity.

High-Hyperdiploid Acute Lymphoblastic Leukemia in Children with LZTR1 Germline Variants

Introduction Firstly described in 1967, hyperdiploidy (HD) is the most frequent genetic abnormality in B-cell- precursor acute lymphoblastic leukemia (BCP-ALL) in children, comprising about 25% of all cases. A not yet exactly defined proportion have predisposing pathogenic germline variants in DNA repair pathway genes, chromatin remodeling factors, transcription factors regulating B-cell development (particularly ETV6) or receptor tyrosine kinases pathway genes like RAS/RAF. Among the latter, mutations have mostly been described in PTPN11 and SOS1, but not yet in other components of this central regulatory hub of cellular communication. Germline loss-of-function (LOF) LZTR1 mutations are typically linked to hereditary nerve sheath tumors. However, it remains largely unknown, if other tumor entities are associated with LZTR1 LOF germline mutations, potentially broadening the spectrum of malignancies associated with RASopathies. Aim Our aim is to understand the frequency and the impact of LZTR1 germline variants in HD BCP-ALL of childhood. Material and Methods We analyzed WES data of 283 children with BCP-ALL for the presence of pathogenic variants in the LZTR1 cancer predisposition gene. For a part of the detected variants, we performed further functional analyses to investigate the effect of the alteration on protein function. We applied a Drosophila model that is particularly suited for functional evaluation of Ras pathway activity. Results We identified LZTR1 germline variants in 10/283 (3.5%) patients (Figure 1). Interestingly, in 6 out of 283 (2.1%) children the LZTR1 variants were classified as pathogenic/likely pathogenic (P/LP). The majority of patients (5/6) harboring a P/LP germline LZTR1 variant presented with a HD BCP-ALL. Only two of our patients showed concomitant phenotypic features indicative of an underlying syndromic condition. Patient P1 presented with a HD BCP-ALL at the age of 9 years and mild psychomotor delay. Sequencing revealed a likely pathogenic variant (p.Arg283Trp) that was not yet reported in association with RASopathy syndromes. The second child P8, also diagnosed with a HD BCP-ALL, carried a well-known autosomal dominant mutation described in Noonan syndrome (NS) variant (p.Gly248Arg). The child was characterized by facial dysmorphism, as well as mild developmental delay, although a diagnosis of NS was not established prior to development of the BCP-ALL. The other three patients had no clinical peculiarities other than HD BCP-ALL. We functionally characterized patient derived LZTR1 variants in dLztr1-depleted ISC. Like wild-type hLZTR1 wt, hLZTR1 p.Arg283Trp and hLZTR1 p.Lys761Arg restored control-like ISC lineage production, suggesting that hLZTR1 p.Arg283Trp and hLZTR1 p.Lys761Arg still regulate Ras ubiquitination. In contrast, hLZTR1 p.Tyr535Ter results in even 1.8-fold higher ISC lineage production than dLztr1-RNAi. Beyond ISC production as a readout, we employed a second experimental paradigm directly addressing Ras signalling activity with a translocating modified ERK sensor. In line with Ras activity control of LZTR1, hLZTR1 wt significantly reduced ERK activity, while the putatively LOF variant hLZTR1 p.Tyr535Ter variant significantly increased Ras pathway activation by 1.4-fold over controls. We also noticed that hLZTR1 p.Tyr535Ter induced extensive membrane blebbing and nuclear fragmentation of GFP positive cells likely indicating programmed cell death. Quantification of apoptotic cells revealed an 11.1-fold increase compared to controls, which was not observed for hLZTR1 p.Arg283Trp and hLZTR1 p.Lys761Arg. Most notably, forced expression of hLZTR1 p.Arg283Trp andhLZTR1 p.Tyr535Ter increased mitotic recombination by 4-fold and 3.4-fold, respectively, which was not observed for the hLZTR1 p. Lys761Arg variant. Conclusion In our cohort, approximately 2% of all children with BCP-ALL harboured a P/LP LZTR1 germline variation, not necessarily linked with clinical appearance of Noonan-syndrome-like features, but to the development of a high hyperdiploid karyotype. By applying a Drosophila model, we demonstrated that patient-derived LZTR1 germline variants affect RAS pathway activation, ERK accumulation, cell proliferation, DNA recombination and apoptosis. Figure 1: Depiction of the ten LZTR1 variants detected in an unselected pediatric cohort of 283 BCP-ALL patients

Paediatric B lymphoblastic leukaemia with hyperdiploidy and a false-positive KMT2A fluorescence in situ hybridization result

The dramatic improvement in the event-free survival of paediatric B-lymphoblastic leukaemia (B-ALL) has led to risk-stratified treatment. Through a combination of clinical features, cytogenetic abnormalities and assessment of treatment response, patients are stratified to receive different intensities of therapy. The presence of high hyperdiploidy (>50 chromosomes) is considered a favourable genetic feature. Conversely, KMT2A fusion genes in B-ALL are associated with a poor prognosis, resulting in intensification of treatment. We present a seven-year-old female with B-ALL, a high hyperdiploid karyotype (56 chromosomes) and KMT2A rearrangement detected on FISH, but with no productive fusion identified. Single nucleotide polymorphism (SNP) array suggested the KMT2A rearrangement was due to chromosome 11 chromothripsis. Subsequent targeted RNA fusion panel and whole transcriptomic sequencing (mRNA-seq) did not detect an expressed KMT2A fusion. Differential expression analyses of the mRNA-seq data led to clustering of this case with other hyperdiploid cases, consistent with the hyperdiploid cytogenetic results. Given the additional intensity and potential toxicity of high-risk treatment, unusual findings by chromosome analysis, FISH and/or chromosomal microarray should prompt consideration of testing for a KMT2A fusion by another method to avoid misclassification.

Clinical features, laboratory characteristics, and outcome of ETP and TCRA/D aberrations in pediatric patients with T-acute lymphoblastic leukemia

BackgroundT-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy with few accepted prognostic factors that limit the efficiency of therapy. The aim of the current study was to assess the clinical and laboratory features of T-cell receptor (TCR) aberrations and early T-cell precursor (ETP) subtype as well as their outcome to therapy.MethodsSixty-three newly diagnosed pediatric T-ALL patients were assessed for the ETP status using immunophenotyping. Screening of TCRA/D aberrations was done by fluorescent in situ hybridization (FISH). The data were correlated to the patients’ clinical features, response to treatment, and survival rates.ResultsSeven patients (11%) had ETP-ALL. The ETP-ALL patients were older (P = 0.013), presented with lower white blood cell (WBC) count (P = 0.001) and lower percentage of peripheral blood (PB) blast cells (P = 0.037), more likely to have hyperdiploid karyotype (P = 0.009), and had been associated with TCRA/D gene amplification (P = 0.014) compared to other T-ALL patients. Of note, the same associations had been significantly observed in patients with TCRA/D gene amplification. Patients with TCRA/D amplification frequently coincided with TCRβ aberrations (P = 0.025). TCR-β aberrations were significantly associated with negative MRD at the end of induction compared to TCR-β-negative patients. There was a nonsignificant trend of ETP-positive cases to have lower overall survival (OS) (P = 0.06). Patients with TCR aberrations had no significant differences regarding disease-free survival (DFS) or OS rates compared to those with normal TCR.ConclusionETP-ALL patients tend to have increased mortalities. There was no significant impact of TCR aberrations on the survival rates of the patients.

Clinical significance of EVI-1 gene expression and aberrations in patient with de-novo acute myeloid and acute lymphoid leukemia

BackgroundAcute leukemia is a common health problem in adults and children, however its exact molecular etiology is still unclear. MethodsThe expression of EVI-1 was assessed in the bone marrow of 178 de-novo acute leukemia patients (101 AML, 71 ALL and 6 MPAL), compared to 40 control subjects. EVI-1 gene aberrations were also assessed in 69 AML patients using Fluorescence in situ hybridization (FISH) technique. ResultsThe expression of EVI-1 was significantly lower in ALL patients compared to control [0.177 (0.002–15.189) vs 0.953 (0.179–1.68); respectively, P = 0.009]. There was no significant difference between AML patients and control group [0.150 (0.0–641) vs 0.953 (0.179–1.68); respectively, P = 0.082]. The sensitivity, specificity, AUC of EVI-1 in ALL were (80.3 %, 60 % and 0.778; respectively, P = 0.009), and (67.3 %, 60 %, 0.667; respectively P = 0.082) in AML patients. One patient showed EVI-1 gene rearrangement in a complex karyotype and four patients showed EVI-1 amplification in hyperdiploid karyotypes. All patients with BCR-ABL fusion were EVI-1 over-expressers (P = 0.010). AML patients with EVI-1 low expression were positively associated with t(8;21)(q22;q22)RUNX1:RUNX1T1 fusion, favorable recurrent translocation, and low genetic risk (P = 0.037, P = 0.023, and P = 0.013; respectively). There was a significant association between low EVI-1 expression and prolonged overall survival (OS) in AML patients, while there was no significant association with the disease-free survival (DFS) (P = 0.048 and P = 0.419). There was no significant impact of EVI-1 expression on OS and DFS rates in ALL patients. ConclusionEVI-1 expression could be a helpful diagnostic, prognostic, and predictive biomarker for acute leukemia especially in AML.

Aneuploidy in the Pearl Oyster Pinctada radiata (Leach, 1814): Evidence for Nonrandom Chromosome Loss and Gain in Marine Bivalves

Aneuploidy, or presence of an abnormal number of chromosomes, has been commonly observed in marine bivalves. This phenomenon has also been shown to be negatively correlated with growth and survival rates in several species of oysters and clams. The impact of pollutants on the aneuploidy level in bivalves has also been previously demonstrated. Over the past two decades, evidence of nonrandom chromosomal loss has been demonstrated, with the identification of the missing chromosomes in aneuploid karyotypes reported in several species. The results have shown that only a few pairs were preferentially affected by the loss of one homologue chromosome in different species of oysters and clams. Recently, during the genotoxicity assessment of the marine environment in Qatar using the pearl oyster Pinctada radiata (Leach, 1814) as model and surrogate species, we observed hypodiploid and hyperdiploid karyotypes. Hyperdiploidy was more frequent, which is highly uncommon in bivalves. The identification of the extra and missing chromosomes in aneuploid cells showed that pairs 4, 5, 12, and 13 were found to be more susceptible than others in having an extra individual chromosome. The same set of pairs showed a tendency to lose one homologue chromosome. Several hypotheses on the preferential chromosomal susceptibility in bivalves, in general, are discussed.

The Independent Adverse Prognostic Significance of 1q21 Gain/Amplification in Newly Diagnosed Multiple Myeloma Patients

Background Multiple myeloma (MM) is a hematological malignancy with proliferation of monoclonal plasma cells which has complex genetics and prognostic heterogeneity. It involves a variety of primary genetic abnormalities, including t (4; 14), t (11; 14), t (14,16) and hyperdiploid karyotypes, as well as secondary genetic abnormalities, including chromosome copy number abnormalities (1q21+, 1p-, 13q-, 17p-, etc) and secondary translocations like MYC. As the most common secondary genetic event, 1q21+ occurs in about 30-40% of NDMM patients while the proportion is especially higher in Chinese population, accounting for 59.7% (96/161) by a domestic study in 2022, it is closely related to the situation that MM patients may have long disease duration and late stage when initial diagnosed in China. Despite its frequency, considerable debate remains regarding to the prognostic impact of 1q21+ in NDMM, 1q21 status hasn't been included among the high-risk markers listed by the IMWG R-ISS stage, and neither in Chinese guidelines. If 1q21+ is included as one of the poor prognostic factors, it will greatly increase the proportion of high-risk patients in NDMM patients. So, our center has begun to take 1q21 seriously as a heterogeneity problem for clinical discussion. Methods 248 NDMM patients admitted in The First Affiliated Hospital of Soochow University from September 01, 2018 to August 31, 2021 of a VRD clinical study, with VRD in combination with ASCT or VRD treatment for 8 cycles, were retrospectively analyzed. 135 cases (54.4%) had 1q21+ by CD38-sorted fluorescence in situ hybridization (FISH), among which 153 patients were compared for the involved genes by CytoScan, focusing on the clinical characteristics, treatment response and prognostic significance by combining FISH and CytoScan technology complementary. Results Among the 248 NDMM patients, 54.4% patients with 1q21+ were more likely to have anemia, hypoalbuminemia, renal insufficiency, high lactate dehydrogenase and high proportion of R-ISS-III stage, and are more likely to be combined with 13q14 deletion, t(4;14), and 1p deletion，and they are all at middle-risk or high-risk groups defined by Prognostic Index score. Multivariate analysis showed that 1q21 gain/amplification was an independent adverse prognostic factor (PFS HR=2.358, 95%CI 1.286-4.324, P=0.006; OS HR=2.598, 95%CI 1.050-6.425, P=0.039). 1q21+ subgroup had an inferior outcome (PFS P=0.0133, OS P=0.0293) (Figure 1a). According to the mSMART3.0 stages, double-hit and triple-hit group had the worst prognosis, with a median PFS of 22 months and a median OS of 32 months. Both PFS and OS were clinically significant (P<0.0001), as shown in Figure 1b. Furthermore 1q21 amplification with more than 4 copy numbers had a shorter PFS than 1q21 gain with 3 copy numbers (24 months vs not reached, P=0.0403), but the OS difference hasn't been not clinically significant (Figure 1c). The positive proportion of 1q21 had no effects on prognosis，while the status of 1q21 in the main clone rather than in the subclone defined by CytoScan when the proportion of abnormal clone populations are differed more than 30%, was an adverse factor affecting the prognosis (PFS P=0.0172, OS P=0.1260). (Figure 1d). ASCT plays an important role in the prognostic survival of 1q21 gain and amplification patients (P<0.05). Outcomes of 1q have been widely discussed in CRD/CTD scheme of Myeloma XI, KRd/KCD scheme of FORTE, VRD/PAD of HOVON65 and so on, our study focusing on the patients with VRD +/- ASCT is also unique, demonstrating that the prognosis of 1q21+ in VRD scheme is also poor, but ASCT can overcome the adverse effects significantly. Conclusions Patients with 1q21+ have clinically significant end-stage organ damage and higher tumor burden, more likely to combine 13q14-, t(4;14), 1p32- and other cytogenetic abnormalities. 1q21+ is an independent high-risk cytogenetic factor for poor prognosis in NDMM patients, of which 4 or more copy numbers and main clone position significantly associated with prognosis results. By combining FISH, CytoScan and other technologies with related abnormalities such as 1q21+，17p-, 1p32-，t (4;14), t(14;16), etc., clinical characteristics, efficacy evaluation, and prognosis can be analyzed more accurately, aiming to identify patients with poor prognosis earlier and enhancing the possibility of moving forward to the treatment strategy based on risk stratification in the future. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

The Landscape of Small Nucleolar RNA Expression in Multiple Myeloma

Background Small nucleolar RNAs (snoRNAs) are non-coding RNAs involved in the maturation of ribosome RNAs and various other biological processes. Emerging evidence demonstrates that snoRNAs play an essential role in tumor initiation and progression. However, their role in multiple myeloma (MM) pathogenesis remains poorly characterized. To date, the profiling of small RNAs in MM has mainly focused on microRNAs and approaches are confined to PCR- or array-based techniques. Here, we used next generation sequencing (NGS) to explore the snoRNA expression patterns of MM patients and to identify the association between snoRNAs and mRNAs, molecular subgroups of MM and clinical parameters. Methods Purified CD138+ cells from 71 newly diagnosed MMs and 4 refractory/relapsed MMs were included. Three CD19+ B cell samples from healthy donors were used as control. Total RNA was isolated with the AllPrep DNA/RNA kit (Qiagen, Germany). The mRNA and snoRNA NGS libraries were prepared using the Illumina TruSeq stranded mRNA and the NEBNext multiplex small RNA library kit, respectively. Sequencing of mRNA and snoRNA was performed on an Illumina NextSeq and NovaSeq 6000 PE 100 S1 platform, respectively. Paired-end RNA-seq reads were mapped to the hg19 reference genome using STAR. Gene expressions were quantified using featureCounts. Differentially expressed mRNAs and snoRNAs were identified using DESeq2. The Kaplan-Meier method was used for survival analyses. Progression-free survival (PFS) time was measured from enrollment to relapse or death from any cause, whichever occurred first. Results Using NGS, we observed expression of 625 full-length snoRNAs. Compared to normal B cells high levels of snoRNA expression were detected in MM plasma cells. Looking for associations between snoRNA expression and molecular subgroups of MM, we found an upregulation of 50 snoRNAs in patients with a hyperdiploid karyotype. The pattern of upregulation supported a regulatory mechanism in this molecular subgroup that goes beyond a pure copy-number effect. Even in patients with multiple trisomies the overwhelming majority (82%) of upregulated snoRNAs were located on chromosome 15, including the SNORD115 family on 15q11. In patients with gain of 1q21, all snoRNAs located on 1q25 were upregulated and the highest expression level of those snoRNAs appeared in patients with amp1q, indicating a copy-number effect. SNORD78, which was recently shown to impact outcome in prostate cancer and lung cancer, was significantly overexpressed in gain1q patients and defined a subgroup with inferior PFS (p =0.019) and overall survival (p = 0.011). SCARNA22, which was upregulated in patients with a t(4;14), was another snoRNA with a negative impact on PFS (31.06 months vs unreached, p = 0.007). To further characterize MM with upregulation of prognostically relevant snoRNAs, we analyzed bulk RNAseq of CD138-enriched MM cells and performed a pathway enrichment analysis. Comparing SNORD78 high expression group with the low group, we found 537 upregulated genes, e.g.SH2D2A, and CDK1, and 229 downregulated genes. Differentially expressed genes were enriched for cell cycle and chromosome segregation. For SCARNA22, we found 963 up- and 219 down-regulated genes. These showed enrichment for cell adhesion (upregulated in SCARNA22high) and protein targeting to the membrane or the endoplasmic reticulum (downregulated in SCARNA22high). Conclusion In this study we provide first insights into the expression patterns of snoRNAs in MM by deep sequencing. We identified snoRNAs dysregulated in MM subgroups, with two of them being associated with poor outcome. This study also shows that expression of particular snoRNAs is associated with specific chromosome gains, which is a common element in MM. Disclosures No relevant conflicts of interest to declare.

The kinetics of blast clearance are associated with copy number alterations in childhood B-cell acute lymphoblastic leukemia

We analyzed the pattern of whole-genome copy number alterations (CNAs) and their association with the kinetics of blast clearance during the induction treatment among 195 pediatric patients with B-cell precursor acute lymphoblastic leukemia (BCP-ALL) who displayed intermediate or high levels of minimal residual disease (MRD). Using unsupervised hierarchical clustering of CNAs > 5 Mbp, we dissected three clusters of leukemic samples with distinct kinetics of blast clearance [A – early slow responders (n=105), B – patients with persistent leukemia (n=24), C – fast responders with the low but detectable disease at the end of induction (n=66)] that corresponded with the patients’ clinical features, the microdeletion profile,the presence of gene fusions and patients survival. Low incidence of large CNAs and chromosomal numerical aberrations occurred in cluster A which included ALL samples showing recurrent microdeletions within the genes encoding transcription factors (i.e., IKZF1, PAX5, ETV6, and ERG), DNA repair genes (XRCC3 and TOX), or harboring chromothriptic pattern of CNAs. Low hyperdiploid karyotype with trisomy 8 or hypodiploidy was predominantly observed in cluster B. Whereas cluster C included almost exclusively high-hyperdiploid ALL samples with concomitant mutations in RAS pathway genes. The pattern of CNAs influences the kinetics of leukemic cell clearance and selected aberrations affecting DNA repair genes may contribute to BCP-ALL chemoresistance.

The Vitamin D Status in Children With Newly Diagnosed Acute Lymphoblastic Leukemia and Its Potential Impact on the Primary Symptoms of Leukemia and Course of Induction Treatment.

Vitamin D deficiency is ubiquitous within the population of children. A similar problem is recognized among pediatric patients with acute lymphoblastic leukemia. The purpose of this study was to analyze the prevalence of vitamin D deficiency and to investigate the connection between vitamin D status and the course of induction treatment of ALL. A cross-sectional study including 59 patients with newly diagnosed ALL from May 2017 until November 2020. Vitamin D deficiency was found in 39% of the patients. There were no seasonal differences in vitamin D status. Patients with optimal 25(OH)D concentration presented more profound thrombocytopenia (P=0.015) and required more frequent platelet transfusions (P=0.018). Good prognosis factors such as B phenotype and hyperdiploidy were also more frequent among children with higher 25(OH)D concentration (P=0.01 and 0.014, respectively). The study showed that patients with a higher serum concentration of 25(OH)D presented deeper thrombocytopenia and needed more frequent transfusions. Moreover, those patients showed higher rates of B-cell leukemia and hyperdiploid karyotype. We did not find any influence of the possible exposure to sunlight (defined as the season of the year on admission) on serum 25(OH)D concentration, which supports the argument for supplementing vitamin D all year round. Moreover, the supplementing of vitamin D seems to be safe and does not cause any renal complications connected to calcium and phosphorus imbalance as no correlation between their levels and 25(OH)D concentration was found.

First Cytogenomic Characterization of the Murine Testicular Tumor Cell Line I-10

After being established in 1967, the commercially available murine Leydig cell tumor line I-10 has been used in almost 50 published studies. I-10 has not been characterized, either at the chromosomal/ cytogenetic level or the genetic level, similar to many other murine tumor cell lines. In this study, we performed molecular karyotyping and multicolor banding-based molecular cytogenetics. A slightly hyperdiploid karyotype with 43 chromosomes was described. The main aberrations comprised several unbalanced translocations and three unusual rearrangements (two dicentric derivatives and one neocentric derivative). Nine regions showed copy number gains, and only five small chromosomal parts showed loss of copy numbers. A standardized translation of these imbalances in the human genome was performed, which showed a 63% overlap of the detected imbalances with testicular germ cell tumors, a 53% concordance with human spermatocytic seminomas and non-seminomas, and only a 36% overlap (approx.) of large copy number gains and losses were similar to the corresponding human Leydig cell tumors. However, no Y-chromosome was detected in this male-derived cell line. Overall, the I-10 cell line was found to be a testicular germ cell tumor model and cannot be treated as a model that is specific to human Leydig cell tumors. At best, it might be suited as a model for an early onset of Leydig cell tumors.

Allogeneic Hematopoietic Cell Transplantation for Acute Myeloid Leukemia with Hyperdiploid Complex Karyotype: A Study from the Acute Leukemia Working Party (ALWP) of the European Society for Blood and Marrow Transplantation (EBMT)

Introduction: Cytogenetics remains one of the most important prognostic factors in acute myeloid leukemia (AML) patients, even for outcomes after allogeneic hematopoietic cell transplantation (allo-HCT). Complex karyotype (CK) constitutes a cytogenetic category with a very adverse prognosis in this setting. However, CK is a heterogenous and loosely defined category which comprises a high diversity of cytogenetic subtypes, which is highly enriched with specific cytogenetic subtypes characterized by losses of chromosomal material at critical regions known to confer a poor prognosis per se, such as monosomal karyotype, del(7q)/-7, del(5q)/-5 or abnormalities leading to 17p region loss. On the contrary, rare AML cases characterized with only multiple numerical abnormalities known as pure hyperdiploid karyotype (HDK), have a controversial prognosis. We hypothesized that pure complex HDK AML has a distinct and much better prognosis after allo-HCT compared to non-HDK, CK AML.Methods: We selected from the EBMT registry adult patients with AML and a full cytogenetic report. HDK was defined by the presence of 49 chromosomes or more. Patients were then stratified by pure HDK (pHDK) and HDK with other cytogenetic abnormalities (HDK+), characterized by HDK and the presence of a prognostic-defining cytogenetic abnormality such as del(5q)/-5, del(7q)/-7, del(17p)/-17/i(17q), inv(3q21-26)/t(3;3)(q21;q26) or t(9;22). We included only first allo-HCT from a sibling or unrelated donor (UD) performed between 2000 and 2018.Results: A total of 236 patients were identified as having HDK. There were 95 pHDK and 141 HDK+. Median age at transplantation was 53 years (range, 18-74) and median follow-up was 43 months (range, 35-56). A diagnosis of secondary AML was reported in 48 patients (20%). At the time of allo-HCT, 180 patients (76%) were in first remission (CR1), and 56 were beyond CR1 (24%). Eighty-five (39%) patients received an allo-HCT from a sibling donor, with more matched unrelated donors (MUD) in HDK+ patients (p=0.02). Most patients (70%) had a Karnofsky performance status (KPS) score of more than 90% at the time of transplantation. A myeloablative conditioning regimen was administered in 46% of the patients. In vivo T-cell depletion was part of the regimen in 66% of the patients. The most frequent trisomies were trisomy 8, 21, 13, and 22.The 2-year probability of non-relapse mortality (NRM) was 26% for the entire cohort. The 2-year probability of LFS was 50% for pHDK and 31% for HDK+ (p=0.003). The 2-year probability of overall survival (OS) was 57% for pHDK and 36% for HDK+ (p=0.007). The 2-year cumulative incidence of relapse (RI) was 22% for pHDK and 44% for HDK+ (p=0.001) (Figure 1). The cumulative incidence of grade II-IV acute graft-versus-host disease (GvHD) and chronic GvHD was 34% and 33%, respectively, for the entire cohort. Finally, the 2-year probability of GvHD and relapse-free survival (GRFS) was 36% for pHDK and 21% for HDK+ (p=0.01). On multivariate analysis, pHDK remained associated with significantly better LFS, OS and GRFS and higher RI (all p-values<0.004). Age was associated with lower OS (p=0.05). Being in remission at the time of allo-HCT was associated with better LFS, OS and GRFS, and lower NRM and RI (all p-values<0.02). Secondary AML, donor type, KPS, and conditioning regimen intensity were not associated with any outcome in multivariate analysis.Conclusions: AML with pHDK has a better outcome after allo-HCT in terms of RI, LFS, OS and GRFS. pHDK AML constitutes probably a distinct cytogenetic entity from HDK+ or other non-hyperdiploid CK AML. CK remains a strong indication for allo-HCT, but the type of abnormalities included in CK significantly influences the outcome and should guide how to manage patients after allo-HCT in terms of immunosuppression withdrawal or prophylactic/preemptive post-transplant interventions such as use of hypomethylating agents or donor lymphocyte infusions. [Display omitted] DisclosuresLabopin: Jazz Pharmaceuticals: Honoraria. Ganser: Jazz Pharmaceuticals: Honoraria; Novartis: Honoraria; Celgene: Honoraria. Socie: Alexion: Research Funding. Forcade: Novartis: Other: travel grant. Chalandon: Incyte, BMS, Pfizer, Abbie, MSD, Roche, Novartis, Gilead, Amgen, Jazz, Astra Zenec: Other: Travel EXpenses, Accomodation; Incyte, BMS, Pfizer, Abbie, MSD, Roche, Novartis, Amgen: Other: Advisory Board; Incyte: Speakers Bureau. Yakoub-Agha: Jazz Pharmaceuticals: Honoraria. Kröger: Novartis: Research Funding; Riemser: Honoraria, Research Funding; Sanofi: Honoraria; Neovii: Honoraria, Research Funding; Jazz: Honoraria, Research Funding; Gilead/Kite: Honoraria; Celgene: Honoraria, Research Funding; AOP Pharma: Honoraria. Esteve: Jazz: Consultancy; Bristol Myers Squibb/Celgene: Consultancy; Abbvie: Consultancy; Novartis: Consultancy, Research Funding; Astellas: Consultancy; Pfizer: Consultancy; Novartis: Research Funding. Mohty: Sanofi: Honoraria, Research Funding; Pfizer: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Jazz: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Gilead: Honoraria; Celgene: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria; Astellas: Honoraria; Amgen: Honoraria; Adaptive Biotechnologies: Honoraria.

Establishment and Characterization of a Human Primary Myelofibrosis Cell Line

Aims: Primary myelofibrosis (PMF) is a myeloproliferative neoplasm (MPN) characterized by clonal proliferation of stem cells and myeloid cells. JAK2, CARL, and MPL mutations could be detected in most patients, but 15% of PMF patients could be absent of these three gene mutations. PMF has shorter median survival time and poorer prognosis when compared with closely related MPNs, polycythemia vera (PV) and essential thrombocythemia (ET). Allogenic hematopoietic stem cells (allo-HSCT) is the only curative therapy for PMF patients, however transplantation-related complications and deaths were observed in more than 50% patients. Hydroxyurea and Ruxolitinib are commonly used drugs to improve clinical symptoms of PMF patients, but lack of anti-tumor activities. These drugs could not reverse bone marrow fibrosis or induce cytogenetic remission. Basic research work of PMF is limited as to the lack of human PMF cell line. Here, we aimed to establish and characterize a patient-derived human PMF cell line, which would provide a useful tool for PMF research and screenings for novel drugs.Methods: The bone marrow cells were obtained from a 61-year-old male patient, who was diagnosed as PMF for 2 years. Mono-nuclear cells were isolated and cultured in a continuous culture system. The cells were characterized by different methods, including STR profiling, morphology observation with Giemsa staining, flow cytometry, chromosome analysis, Epstein-Barr virus (EBV) detection, mycoplasma detection, whole-genome-exon sequencing, and cell proliferation assay.Results: The cells have continued to grow in liquid culture for more than 50 passages using the same culture conditions. Doubling time was about 48-72 hours. The STR profiling identified that the cultured cells and the patient's bone marrow cells were from the same origin. The cells are free from EBV and mycoplasma. Giemsa-Wrights staining showed primitive erythrocytes (Figure A), which was consistent with CD71 positive detected by flow cytometry. Chromosome analysis revealed a hyperdiploid karyotype, which was 47, XY,+12[1]/48,idem,+9[9]. Whole-genome-exon sequencing identified mutations of ASXL1, TP53, IKZF1, IDH1, FLT3, and TET1 (Figure B). Now this cell line, designated ZYXY-M2, is collected by China center for type culture collection (CCTCC).Discussion: Established cell lines are invaluable tools in cell biology. Right now, HEL and SET-2 are two cell lines that are most widely used in MPN-related researches. HEL is an erythroleukemia cell line which was derived from a patient with leukemia transformation of Hodgkin's disease, and SET-2 is a megakaryoblastic cell line which was derived from a patient with leukemic transformation of ET. Here, we established a cell line, ZYXY-M2, derived from a PMF patient and it would prove to be a valuable model for the study of PMF. ZYXY-M2 could help to explore the pathogenesis and development of PMF, novel drug screening, and may also help to set up xenograft PMF mouse models. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Benchmarking of Whole Genome Sequencing (WGS) and Whole Transcriptome Sequencing (WTS) As Diagnostic Tools for the Genetic Characterization of Acute Myeloid Leukemia (AML) and Acute Lymphoblastic Leukemia (ALL) in Adults

Background: In AML and ALL the application of WHO classification and ELN guidelines requires a combination of cytogenetics and targeted sequencing for specific mutations to determine the diagnostic and prognostic subgroup. WGS and WTS have emerged as comprehensive techniques that allow the simultaneous analysis and identification of all genetic alterations in a single approach with possible turnaround times of 1 week.Aim: Evaluate the accuracy of WGS and WTS in providing all relevant genetic information in a clinical setting.Patients and Methods: The cohort comprised 738 AML, 293 BCP-ALL and 124 T-ALL. The diagnosis was established following WHO guidelines. WGS (100x, 2x151bp) and WTS (50 Mio reads, 2x101bp) were performed on a NovaSeq instrument. Variants were called with Strelka2, Manta and GATK using a tumor w/o normal pipeline, fusions with Arriba, STAR-Fusion and Manta.Results: The combination of WGS and WTS detected all chromosomal and molecular abnormalities in the AML and ALL cohorts relevant for disease stratification and prognostication as identified by chromosome banding analysis (CBA) and targeted panel sequencing (TPS). A very high concordance between CBA and WGS was revealed for the detection of balanced structural variants (SV) with the added benefit of WGS to also detect cytogenetically cryptic rearrangements (i.e.: ETV6-MN1, NUP98-KDM5A), which all were confirmed either by FISH or RT-PCR. Fusion calling by WTS identified 96% of the WHO subtype defining rearrangements and detected 20 additional fusion transcripts relevant for disease stratification (e.g. EP300-ZNF384, TCF3-HLF) including 9 fusion transcripts that led to prognostic reassignment or could serve as a potential treatment target. Breakpoints of unbalanced SV can occur in repetitive sequences of the genome, hampering the detection by WGS. However, adding copy number alteration (CNA) calls to the analyses allows also reliable identification of unbalanced SV.WGS outperformed CBA in cases with insufficient in vitro proliferation due to suboptimal pre-analytics (i.e. longer transport time) and identified 36 chromosomal aberrations in 12 cases with CBA not evaluable. WGS's independence of in vitro cell proliferation was most impactful in ALL: 40 T-ALL cases showed a normal karyotype according to CBA. WGS detected SVs in 16 (40%) and CNAs in 20 (50%) of these cases, confirming the normal karyotype for only 9 samples. In the BCP-ALL cohort, CNV analysis identified 29 low hypodiploid and 16 high hyperdiploid karyotypes, 6 of which were missed by CBA. Due to the higher resolution and unrestricted, genome-wide assessment, WGS detected relevant gene deletions (RB1, ERG, PAX5, CDKN2A, IKZF1, ETV6, BTG1) in 59% of ALL cases, providing additional diagnostic and prognostic information. In the AML cohort CBA and WGS detected 795 CNA concordantly. In addition WGS called 54 CNA with size 1-5 MB (below the detection limit of CBA), i.e. 3 BCOR deletions in inv(3)(q21q26) cases and 67 CNA with size > 5 MB, which were missed by CBA. 35 CNA were missed by WGS due to small clone sizes (median 6% as determined by FISH). WGS detected copy neutral loss of heterozygosity (CN-LOH) in AML most frequently on 21q (n=17), 4q (n=15), 13q (n=15), 11q (n=13) and in T-ALL on 9p (n=19), mostly encompassing CDKN2A/B deletions. Expression profiling provided additional diagnostic information for 57 ALL cases (41 BCR-ABL1-like, 16 DUX4 rearranged) that can only insufficiently be obtained by WGS or CBA. WGS reliably detected all gene mutations with a VAF > 15% (n = 647) identified by TPS encompassing especially all mutations in genes relevant for WHO diagnosis and prognostication. 26/171 mutations with a VAF < 15% were missed by WGS. Evaluation of WGS data for 121 genes recurrently mutated in hematologic neoplasms revealed an additional 2 mutations per sample on average (range: 0-9) which might qualify as targets for therapy.Conclusions: WGS and WTS provide all necessary genetic information to accurately determine the diagnostic and prognostic subgroup according to WHO and ELN guidelines in AML and ALL. Compared to today's gold standards, these novel methods provide a comprehensive genome wide characterization with higher resolution that directly identifies genes of impact, offering the basis for targeted treatment selection and monitoring of residual disease. Both can be implemented with automated analysis pipelines, consequently reducing time and error rates. [Display omitted] DisclosuresHaferlach: MLL Munich Leukemia Laboratory: Other: Part ownership. Kern: MLL Munich Leukemia Laboratory: Other: Part ownership. Haferlach: MLL Munich Leukemia Laboratory: Other: Part ownership.

Acute Lymphoblastic Leukemia

Acute Lymphoblastic Leukemia