Detection of clinically relevant variants in the gene below 10% allelic frequency: A multicenter study by ERIC, the European Research Initiative on CLL.

In chronic lymphocytic leukemia, the reliability of next-generation sequencing (NGS) to detect variants ≤10% allelic frequency (low-VAF) is debated. We tested the ability to detect 23 such variants in 41 different laboratories using their NGS method of choice. The sensitivity was 85.

Cancer associated variant enrichment CAVE, a gene agnostic approach to identify low burden variants in chronic lymphocytic leukemia.

Intratumoral heterogeneity is an important clinical challenge because low burden clones expressing specific genetic alterations drive therapeutic resistance mechanisms. We have developed CAVE (cancer-associated variant enrichment), a gene-agnostic computational tool to identify specific enrichment of low-burden cancer driver variants in next-generation sequencing (NGS) data. For this study, CAVE was applied to TP53 in chronic lymphocytic leukemia (CLL) as a cancer model.

Identification of the Axis β-Catenin-BTK in the Dynamic Adhesion of Chronic Lymphocytic Leukemia Cells to Their Microenvironment.

In the microenvironment, cell interactions are established between different cell types to regulate their migration, survival and activation. β-Catenin is a multifunctional protein that stabilizes cell-cell interactions and regulates cell survival through its transcriptional activity. We used chronic lymphocytic leukemia (CLL) cells as a cellular model to study the role of β-catenin in regulating the adhesion of tumor cells to their microenvironment, which is necessary for tumor cell survival and accumulation.

Inhibition of a new AXL isoform, AXL3, induces apoptosis of mantle cell lymphoma cells.

Mantle cell lymphoma (MCL) is an aggressive B-cell non-Hodgkin lymphoma having a poor overall survival that is in need for the development of new therapeutics. In this study, we report the identification and expression of a new isoform splice variant of the tyrosine kinase receptor AXL in MCL cells. This new AXL isoform, called AXL3, lacks the ligand-binding domain of the commonly described AXL splice variants and is constitutively activated in MCL cells.

Different prognostic impact of recurrent gene mutations in chronic lymphocytic leukemia depending on IGHV gene somatic hypermutation status: a study by ERIC in HARMONY.

Recent evidence suggests that the prognostic impact of gene mutations in patients with chronic lymphocytic leukemia (CLL) may differ depending on the immunoglobulin heavy variable (IGHV) gene somatic hypermutation (SHM) status. In this study, we assessed the impact of nine recurrently mutated genes (BIRC3, EGR2, MYD88, NFKBIE, NOTCH1, POT1, SF3B1, TP53, and XPO1) in pre-treatment samples from 4580 patients with CLL, using time-to-first-treatment (TTFT) as the primary end-point in relation to IGHV gene SHM status. Mutations were detected in 1588 (34.

Dihydroorotate dehydrogenase inhibition acts synergistically with tyrosine kinase inhibitors to induce apoptosis of mantle cell lymphoma cells.

Mantle cell lymphoma (MCL) is a non-Hodgkin lymphoma that remains incurable with the treatment options available today. In the present study, we have identified the dihydroorotate dehydrogenase (DHODH), an essential enzyme for the biosynthesis of pyrimidine-based nucleotides, to be overexpressed in MCL in comparison to healthy peripheral blood mononuclear cells (PBMC). In vitro inhibition of the DHODH activity using a newly developed DHODH inhibitor, namely ()-HZ05, can induce MCL cell death in the nanomolar range independently than the P53 status of the investigated cell lines.

Impact of Low-Burden Mutations in the Management of CLL.

In chronic lymphocytic leukemia (CLL), abnormalities are associated with reduced survival and resistance to chemoimmunotherapy (CIT). The recommended threshold to clinically report mutations is a matter of debate given that next-generation sequencing technologies can detect mutations with a limit of detection of approximately 1% with high confidence. However, the clinical impact of low-burden mutations with a variant allele frequency (VAF) of less than 10% remains unclear.

[Relapse of acquired von Willebrand syndrome in a patient non-compliant with Crohn's disease].

We report a case of acquired von Willebrand syndrome relapse in association with Crohn's disease, in a context of non-compliance in a 85-year-old woman suffering from epistaxis and melena. The acquired von Willebrand syndrome is a rare bleeding disorder. This case underlines the importance of maintaining the corticosteroid therapy in order to prevent the reappearance of autoantibodies and the recurrence of this syndrome.

A hotspot mutation in transcription factor IKZF3 drives B cell neoplasia via transcriptional dysregulation.

Hotspot mutation of IKZF3 (IKZF3-L162R) has been identified as a putative driver of chronic lymphocytic leukemia (CLL), but its function remains unknown. Here, we demonstrate its driving role in CLL through a B cell-restricted conditional knockin mouse model. Mutant Ikzf3 alters DNA binding specificity and target selection, leading to hyperactivation of B cell receptor (BCR) signaling, overexpression of nuclear factor κB (NF-κB) target genes, and development of CLL-like disease in elderly mice with a penetrance of ~40%.

Stabilization of β-catenin upon B-cell receptor signaling promotes NF-kB target genes transcription in mantle cell lymphoma.

B-cell receptor (BCR) signaling pathways and interactions with the tumor microenvironment account for mantle cell lymphoma (MCL) cells survival in lymphoid organs. In several MCL cases, the WNT/β-catenin canonical pathway is activated and β-catenin accumulates into the nucleus. As both BCR and β-catenin are important mediators of cell survival and interaction with the microenvironment, we investigated the crosstalk between BCR and WNT/β-catenin signaling and analyzed their impact on cellular homeostasis as well as their targeting by specific inhibitors.

[A primitive plasma cell leukemia with immunoglobulin (Ig) E].

We report here a case of primitive plasma cell leukemia with immunoglobulin (Ig) E. IgE myeloma is an exceptional variant of multiple myeloma, with a very poor prognosis. Its biological diagnosis requires specific analyzes in order to detect IgE gammopathy.

Cytogenetic complexity in chronic lymphocytic leukemia: definitions, associations, and clinical impact.

Recent evidence suggests that complex karyotype (CK) defined by the presence of ≥3 chromosomal aberrations (structural and/or numerical) identified by using chromosome-banding analysis (CBA) may be relevant for treatment decision-making in chronic lymphocytic leukemia (CLL). However, many challenges toward the routine clinical application of CBA remain. In a retrospective study of 5290 patients with available CBA data, we explored both clinicobiological associations and the clinical impact of CK in CLL.

Outcomes and mutational analysis of patients with lower-risk non-del5q myelodysplastic syndrome treated with antithymocyte globulin with or without ciclosporine A.

Immunosuppressive treatment is a disease-modifying therapy for lower-risk myelodysplastic syndromes (MDS). However, IST is relatively rarely used and long-term outcomes of patients are seldom reported. We retrospectively studied outcomes of 20 patients with lower-risk non del 5q MDS with transfusion dependency, with horse or rabbit antithymocyte globulin ± ciclosporine A, and frontline eltrombopag in two of them.

Induction of endoplasmic reticulum calcium pump expression during early leukemic B cell differentiation.

Background: Endoplasmic reticulum (ER) calcium storage and release play important roles in B lymphocyte maturation, survival, antigen-dependent cell activation and immunoglobulin synthesis. Calcium is accumulated in the endoplasmic reticulum (ER) by Sarco/Endoplasmic Reticulum Calcium ATPases (SERCA enzymes). Because lymphocyte function is critically dependent on SERCA activity, it is important to understand qualitative and quantitative changes of SERCA protein expression that occur during B lymphoid differentiation and leukemogenesis.

Obstructive sleep apnoea and related comorbidities in incident idiopathic pulmonary fibrosis.

The objectives of this prospective study were: 1) to determine the prevalence and determinants of obstructive sleep apnoea (OSA) in patients with newly diagnosed idiopathic pulmonary fibrosis (IPF); 2) to determine whether OSA was associated with cardiovascular disease (CVD) as well as increased oxidative stress and levels of IPF biomarkers in the blood.A group of 45 patients with newly diagnosed IPF attended polysomnography. The prevalence of CVD and the severity of coronary artery calcification were investigated by high-resolution computed tomography.

Recommended Guidelines for Validation, Quality Control, and Reporting of Variants in Clinical Practice.

Accurate assessment of gene status in sporadic tumors and in the germline of individuals at high risk of cancer due to Li-Fraumeni Syndrome (LFS) has important clinical implications for diagnosis, surveillance, and therapy. Genomic data from more than 20,000 cancer genomes provide a wealth of information on cancer gene alterations and have confirmed as the most commonly mutated gene in human cancer. Analysis of a database of 70,000 variants reveals that the two newly discovered exons of the gene, exons 9β and 9γ, generated by alternative splicing, are the targets of inactivating mutation events in breast, liver, and head and neck tumors.