ins(X;11)(q28;q23q23) KMT2A/FLNA::ins(11;X)(q23;q28q12) KMT2A/FLNA

Ins(11;X)(q23;q28q12) and ins(X;11)(q28;q23q23) are found so far in acute myelomonocytic leukaemia and carries a poor prognosis. The genes implicated in this disease are KMT2A and FLNA

t(11;16)(q23;q24) KMT2A/USP10

Review on t(11;16)(q23;q24), with data on clinics, and the genes involved

Epigenetic regulator genes direct lineage switching in MLL/AF4 leukaemia

The fusion gene MLL/AF4 defines a high-risk subtype of pro-B acute lymphoblastic leukaemia. Relapse can be associated with a lineage switch from acute lymphoblastic to acute myeloid leukaemia resulting in poor clinical outcomes due to resistance towards chemo- and immuno-therapies. Here we show that the myeloid relapses share oncogene fusion breakpoints with their matched lymphoid presentations and can originate from varying differentiation stages from immature progenitors through to committed B-cell precursors. Lineage switching is linked to substantial changes in chromatin accessibility and rewiring of transcriptional programmes, including alternative splicing. These findings indicate that the execution and maintenance of lymphoid lineage differentiation is impaired. The relapsed myeloid phenotype is recurrently associated with the altered expression, splicing or mutation of chromatin modifiers, including CHD4 coding for the ATPase/helicase of the nucleosome remodelling and deacetylation complex, NuRD. Perturbation of CHD4 alone or in combination with other mutated epigenetic modifiers induces myeloid gene expression in MLL/AF4-positive cell models indicating that lineage switching in MLL/AF4 leukaemia is driven and maintained by disrupted epigenetic regulation

Influence of extraction conditions on the recovery lipids extracted from the dry biomass of duckweed Lemna minor

Previous studies on the composition of lipid content of higher aquatic plants can be found in the literature. The present work aims to study the effect of various solvent extraction systems on the recovery of lipids extracted from the dry biomass of Lemna minor, using the same polar solvent (ethanol) and variating the non-polar solvent as follow: methanol-ethanol, chloroform-ethanol, hexane-ethanol, diethyl ether-ethanol, petroleum ether-ethanol at different volume ratio. The goal is to select a Sohxlet extraction method that shortens the extraction duration and increases the lipid recovery using various solvents. To intensify the extraction process, homogenization was used as a cell disruption method. It is shown that the yield of total lipids is increased by using homogenization from 4.6% to 6.0%. When studying the influence of the solvent system, the highest yield of total lipids was obtained by using hexane-ethanol with a volume ration of 1:1 (8.0% total lipids by dry mass). The yield of lipids recovered from dry biomass of Lemna minor increases by increasing the extraction time. The optimum extraction time was found to be no more than 300 minutes. The composition of the lipid fraction is mainly represented by sterols, fatty acids and triglycerides

Influence of extraction conditions on the recovery lipids extracted from the dry biomass of duckweed Lemna minor

Previous studies on the composition of lipid content of higher aquatic plants can be found in the literature. The present work aims to study the effect of various solvent extraction systems on the recovery of lipids extracted from the dry biomass of Lemna minor, using the same polar solvent (ethanol) and variating the non-polar solvent as follow: methanol-ethanol, chloroform-ethanol, hexane-ethanol, diethyl ether-ethanol, petroleum ether-ethanol at different volume ratio. The goal is to select a Sohxlet extraction method that shortens the extraction duration and increases the lipid recovery using various solvents. To intensify the extraction process, homogenization was used as a cell disruption method. It is shown that the yield of total lipids is increased by using homogenization from 4.6% to 6.0%. When studying the influence of the solvent system, the highest yield of total lipids was obtained by using hexane-ethanol with a volume ration of 1:1 (8.0% total lipids by dry mass). The yield of lipids recovered from dry biomass of Lemna minor increases by increasing the extraction time. The optimum extraction time was found to be no more than 300 minutes. The composition of the lipid fraction is mainly represented by sterols, fatty acids and triglycerides

Reliable Flow-Cytometric Approach for Minimal Residual Disease Monitoring in Patients with B-Cell Precursor Acute Lymphoblastic Leukemia after CD19-Targeted Therapy

We aimed to develop an antibody panel and data analysis algorithm for multicolor flow cytometry (MFC), which is a reliable method for minimal residual disease (MRD) detection in patients with B-cell precursor acute lymphoblastic leukemia (BCP-ALL) treated with CD19-directed therapy. The development of the approach, which was adapted for the case of possible CD19 loss, was based on the additional B-lineage marker expression data obtained from a study of primary BCP-ALL patients, an analysis of the immunophenotypic changes that occur during blinatumomab or CAR-T therapy, and an analysis of very early CD19-negative normal BCPs. We have developed a single-tube 11-color panel for MFC-MRD detection. CD22- and iCD79a-based primary B-lineage gating (preferably consecutive) was recommended. Based on patterns of antigen expression changes and the relative expansion of normal CD19-negative BCPs, guidelines for MFC data analysis and interpretation were established. The suggested approach was tested in comparison with the molecular techniques: IG/TR gene rearrangement detection by next-generation sequencing (NGS) and RQ-PCR for fusion-gene transcripts (FGTs). Qualitative concordance rates of 82.8% and 89.8% were obtained for NGS-MRD and FGT-MRD results, respectively. We have developed a sensitive and reliable approach that allows MFC-MRD monitoring after CD19-directed treatment, even in the case of possible CD19 loss

Immunophenotypic but Not Genetic Changes Reclassify the Majority of Relapsed/Refractory Pediatric Cases of Early T-Cell Precursor Acute Lymphoblastic Leukemia

Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) develops from very early cells with the potential for both T-cell and myeloid differentiation. The ambiguous nature of leukemic blasts in ETP-ALL may lead to immunophenotypic alterations at relapse. Here, we address immunophenotypic alterations and related classification issues, as well as genetic features of relapsed pediatric ETP-ALL. Between 2017 and 2022, 7518 patients were diagnosed with acute leukemia (AL). In addition to conventional immunophenotyping, karyotyping, and FISH studies, we performed next-generation sequencing of the T-cell receptor clonal repertoire and reverse transcription PCR and RNA sequencing for patients with ETP-ALL at both initial diagnosis and relapse. Among a total of 534 patients diagnosed with T-cell ALL (7.1%), 60 had ETP-ALL (11.2%). Ten patients with ETP-ALL experienced relapse or progression on therapy (16.7%), with a median time to event of 5 months (ranging from two weeks to 5 years). Most relapses were classified as AL of ambiguous lineage (n = 5) and acute myeloid leukemia (AML) (n = 4). Major genetic markers of leukemic cells remained unchanged at relapse. Of the patients with relapse, four had polyclonal leukemic populations and a relapse with AML or bilineal mixed-phenotype AL (MPAL). Three patients had clonal TRD rearrangements and relapse with AML, undifferentiated AL, or retention of the ETP-ALL phenotype. ETP-ALL relapse requires careful clinical and laboratory diagnosis. Treatment decisions should rely mainly on initial examination data, taking into account both immunophenotypic and molecular/genetic characteristics

Recognizing Minor Leukemic Populations with Monocytic Features in Mixed-Phenotype Acute Leukemia by Flow Cell Sorting Followed by Cytogenetic and Molecular Studies: Report of Five Exemplary Cases

Mixed-phenotype acute leukemia (MPAL), a rare and heterogeneous category of acute leukemia, is characterized by cross-lineage antigen expression. Leukemic blasts in MPAL can be represented either by one population with multiple markers of different lineages or by several single-lineage populations. In some cases, a major blast population may coexist with a smaller population that has minor immunophenotypic abnormalities and may be missed even by an experienced pathologist. To avoid misdiagnosis, we suggest sorting doubtful populations and leukemic blasts and searching for similar genetic aberrations. Using this approach, we examined questionable monocytic populations in five patients with dominant leukemic populations of B-lymphoblastic origin. Cell populations were isolated either for fluorescence in situ hybridization or for clonality assessment by multiplex PCR or next-generation sequencing. In all cases, monocytic cells shared the same gene rearrangements with dominant leukemic populations, unequivocally confirming the same leukemic origin. This approach is able to identify implicit cases of MPAL and therefore leads to the necessary clinical management for patients