GMO. Artículos

Distinct mutational pattern of myelodysplastic syndromes with and without 5q- treated with lenalidomide

2026-06-01T11:49:31Z

[EN]Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal stem cell disorders characterised by ineffective haematopoiesis leading to peripheral blood cytopenias and an increased risk of transformation to acute myeloid leukaemia (AML) (Haferlach et al., 2014; Makishima et al., 2017). One of the most common cytogenetic alterations is the deletion of the long arm of chromosome 5q [del(5q)], which can be found isolated or with other alterations (10–30% of patients with MDS). Lenalidomide (LEN) has been approved for the treatment of patients with del(5q) low-risk MDS and transfusion dependence. Almost 50% of patients with del(5q) will show a complete cytogenetic remission and 70% of them will reach transfusion independence (List et al., 2006). LEN has also been approved for MDS non-del(5q) transfusion dependent and resistant to erythropoietin-stimulating agents (Santini et al., 2016), suggesting that other factors besides del(5q) modulate response to LEN (Negoro et al., 2016). Herein, we aimed to define the mutational spectrum of patients with MDS with and without del(5q) and define a signature of mutations influencing response to LEN. We collected peripheral blood and/or bone marrow samples from patients with MDS treated with LEN from eight institutions at the Josep Carreras Leukaemia Research Institute (on behalf of the MDS Spanish Group and the MDS French Group) according to the institutional ethic committees and the revised Declaration of Helsinki. We collected 74 samples from patients with MDS at diagnosis or treatment- naïve with LEN follow-up treatment of two or more cycles; 32 patients presented with del(5q), while 42 patients did not have del(5q) in their karyotype (Table S1). The World Health Organization (WHO) classification (2017), Revised International Prognostic Scoring System (IPSS-R) and International Working Group response criteria (IWGc) (Cheson et al., 2006; Greenberg et al., 2012; Dolatshad et al., 2015) were used to classify patients. Responders to LEN included patients with complete and partial response, haematological response and cytogenetic response, while non-responders included patients with treatment failure, stable disease or relapse. We combined results of multi amplicon targeted sequencing with Ion Torrent (Thermo Fisher Scientific, Inc., Waltham, MA, USA) (28 cases) and captured-based targeted sequencing with MiSeq (Illumina, San Diego, CA, USA) (46 cases). Amplicon and capture custom panels included 39 and 82 most recurrently mutated genes in MDS, respectively (Table S2). Capture libraries were generated using the KAPA Library Preparation Kit (Kapa Biosystems, Wilmington, MA, USA), enriched with the SeqCap EZ capture chemistry (Roche, Basel, Switzerland) and sequenced on MiSeq sequencers following a 150 base pairs (bp) paired-end reads Illumina standard protocol. Average coverage per gene was 777×. Reads were aligned against human genome build 19 (hg19) using Burrows-Wheeler Aligner (BWA) 0.7.12 and post-alignment was performed using Genome Analysis Toolkit (GATK) 3.4.46 software package. Libraries for the amplicon-based panel were prepared with Ampliseq (Thermo Fisher Scientific, Inc.) and sequenced in an ion torrent proton sequencer according to the manufacturer’s instructions. Average coverage per genes was 567×. Primary bioinformatic analysis [SAMtools 1.2 (http://www.htslib.org/), VarScan 2.4.0 (http://dkoboldt.github.io/varscan/), and ANNOtate VARiation (https://doc-openbio.readthedocs.io/projects/annovar/en/latest/)] was performed and followed by an in-house protocol (Ibáñez et al., 2016). Variants at highly variable regions, with low coverage (<100×), or a minor allele frequency >1% according to available population databases [Exome Aggregation Consortium (ExAC), Exome Variant Server, 1000 Genomes Project] were filtered out. Mutations were called when the variant allelic frequency (VAF) was >5%. Continuous variable comparisons were performed with Wilcoxon signed-rank tests, while Fisher’s exact test was used to compare variables. Survival curves were calculated using the Kaplan–Meier method and log-rank test were used for comparisons. Two-sided P values < 0·05 were considered as statistically significant.

ATM aberrations in chronic lymphocytic leukemia: del(11q) rather than ATM mutations is an adverse-prognostic biomarker

2026-05-24T00:02:15Z

[EN]Despite the well-established adverse impact of del(11q) in chronic lymphocytic leukemia (CLL), the prognostic significance of somatic ATM mutations remains uncertain. We evaluated the effects of ATM aberrations (del(11q) and/or ATM mutations) on time-to-first-treatment (TTFT) in 3631 untreated patients with CLL, in the context of IGHV gene mutational status and mutations in nine CLL-related genes. ATM mutations were present in 246 cases (6.8%), frequently co-occurring with del(11q) (112/246 cases, 45.5%). ATM-mutated patients displayed a different spectrum of genetic abnormalities when comparing IGHV-mutated (M-CLL) and unmutated (U-CLL) cases: M-CLL was enriched for SF3B1 and NFKBIE mutations, whereas U-CLL showed mutual exclusivity with trisomy 12 and TP53 mutations. Isolated ATM mutations were rare, affecting 1.2% of Binet A patients and <1% of M-CLL cases. While univariable analysis revealed shorter TTFT for Binet A patients with any ATM aberration compared to ATM-wildtype, multivariable analysis identified only del(11q), trisomy 12, SF3B1, and EGR2 mutations as independent prognosticators of shorter TTFT among Binet A patients and within M-CLL and U-CLL subgroups. These findings highlight del(11q), and not ATM mutations, as a key biomarker of increased risk of early progression and need for therapy, particularly in otherwise indolent M-CLL, providing insights into risk-stratification and therapeutic decision-making.

Examining the Effects of the RUNX1 p.Leu43Ser Variant on FPD/AML Phenotypes Using a CRISPR/Cas9-Generated Knock-In Murine Model

2026-05-24T00:02:12Z

[EN]Germline heterozygous variants in RUNX1 lead to Familial Platelet Disorder with Myeloid Leukemia Predisposition (FPD/AML). Cellular and/or animal models are helpful to uncovering the role of a variant in disease progression. Twenty-five mice per genotype (RUNX1WT/WT, RUNX1WT/L43S, RUNX1L43S/L43S), previously generated by CRISPR/Cas9, and nine sub-lethally irradiated mice per genotype were investigated. Peripheral blood (PB), bone marrow (BM), and spleen samples were analyzed by flow cytometry and histopathology. Deregulated genes were analyzed by RNA-seq in BM. An aberrant myeloid Mac1+Sca1+ckit- population in the PB, BM, and spleen of two homozygous and one heterozygous mouse was observed, as well as BM hypercellularity. No Mac1+Sca1+ckit- cells were detected in any RUNX1WT/WT mice. Moreover, the spleen of both homozygous mice showed destruction of the white/red pulp and the presence of apoptotic cells. The aberrant population was also detected in four irradiated mice, two heterozygous and two homozygous, in their PB, BM, and spleen. RNA-seq studies showed 698 genes significantly deregulated in the three non-irradiated Mac1+Sca1+ckit- mice vs. six healthy mice, highlighting the alteration of genes involved in apoptosis and DNA repair. These results indicate that the homozygous form of the variant p.Leu43Ser may contribute to the pathogenesis of aberrant cells.

SAMHD1 dysfunction impairs DNA damage response and increases sensitivity to PARP inhibition in chronic lymphocytic leukemia

2026-05-24T00:02:08Z

[EN]Chronic lymphocytic leukemia (CLL) is a clinically and genetically heterogenous disease. Recent next-generation sequencing (NGS) studies have uncovered numerous low-frequency mutated genes in CLL patients, with SAMHD1 emerging as a candidate driver gene. However, the biological and clinical implications of SAMHD1 mutations remain unclear. Using CRISPR/Cas9, we generated CLL models to investigate the impact of SAMHD1 deficiency on pathogenesis and explore therapeutic strategies. Moreover, we performed NGS in treatment-naïve CLL patients to characterize SAMHD1 mutations and employed RNA-sequencing to evaluate their clinical significance. Our study shows that SAMHD1 inactivation impairs the DNA damage response by reducing homologous recombination efficiency through BRCA1 and RAD51 dysregulation. Importantly, SAMHD1 colocalizes with BRCA1 at DNA damage sites in CLL cells. This research also identifies that SAMHD1-mutated cells are more sensitive to PARP inhibition. Clinically, SAMHD1 dysfunction negatively impacts clinical outcome of CLL cases: SAMHD1 mutations reduce failure-free survival (median 46 vs 57 months, p = 0.033), while low SAMHD1 expression associates with shorter time to first treatment (median 47 vs 77 months; p = 0.00073). Overall, this study elucidates that SAMHD1 dysfunction compromises DNA damage response mechanisms, potentially contributing to unfavorable clinical outcomes in CLL, and proposes PARP-inhibitors as a potential therapeutic approach for SAMHD1-mutated CLL cells.

Preferential Genetic Pathways Lead to Relapses in Adult B-Cell Acute Lymphoblastic Leukemia

2026-05-20T00:03:25Z

[EN]Adult B-cell acute lymphoblastic leukemia (B-ALL) is characterized by genetic heterogeneity and a high relapse rate, affecting over 40% of adults. However, the mechanisms leading to relapse in adults are poorly understood. Forty-four adult B-ALL patients were studied at both diagnosis and relapse by next-generation sequencing (NGS). Four main genetic pathways leading to relapse in adults were identified: IKZF1plus genetic profile, RAS mutations and TP53 alterations in Ph-negative B-ALL and acquisition of ABL1 mutations in Ph-positive patients. The most frequently deleted gene at diagnosis was IKZF1 (52%), and 70% of these patients had IKZF1plus profile. Notably, 88% of patients with IKZF1plus at diagnosis retained this genetic profile at relapse. Conversely, the acquisition of RAS mutations or the expansion of subclones (normalized variant allele frequency < 25%) present from diagnosis were observed in 24% of Ph-negative patients at relapse. In addition, 24% of relapses in the Ph-negative cohort could potentially be driven by TP53 alterations. Of these cases, five presented from diagnosis, and four emerged at relapse, mostly as "double-hit" events involving both TP53 deletion and mutation. In Ph-positive B-ALL, the main genetic finding at relapse was the acquisition of ABL1 mutations (86%). Three clonal evolution patterns were identified: the persistent clone trajectory (25%), the expanding clone trajectory (11%) and the therapy-boosted trajectory (48%). Our results reveal the presence of preferential biological pathways leading to relapse in adult B-ALL. These findings underscore the need for personalized therapeutic strategies to improve clinical outcomes in adult patients with B-ALL.

Sex Differences in Gut Microbiota and Their Relation to Arterial Stiffness (MIVAS Study)

2026-05-20T00:03:22Z

[EN]Recent research highlights the potential role of sex-specific variations in cardiovascular disease. The gut microbiome has been shown to differ between the sexes in patients with cardiovascular risk factors. The main objective of this study is to analyze the differences between women and men in the relationship between gut microbiota and measures of arterial stiffness. We conducted a cross-sectional study in Spain, selecting 180 subjects (122 women, 58 men) aged between 45 and 74. Subjects with arterial stiffness were identified by the presence of at least one of the following: carotid-femoral pulse wave velocity (cf-PWV) above 12 mm/s, cardio-ankle vascular index (CAVI) above nine, or brachial-ankle pulse wave velocity (ba-PWV) above 17.5 m/s. All other cases were considered subjects without arterial stiffness. The composition of the gut microbiome in fecal samples was determined by 16S rRNA sequencing. We found that women have a more diverse microbiome than men (Shannon, p < 0.05). There is also a significant difference in gut microbiota composition between sexes (Bray-Curtis, p < 0.01). Dorea, Roseburia, and Agathobacter, all of them short-chain fatty-acid producers, were more abundant in women's microbiota (log values > 1, p-value and FDR < 0.05). Additionally, Blautia was more abundant in women when only the subjects with arterial stiffness were considered. According to logistic regression, Roseburia was negatively associated with arterial stiffness in men, while Bifidobacterium and Subdoligranulum were positively related to arterial stiffness. In the Spanish population under study, women had higher microbiome diversity and potentially protective genera. The host's gender determines the influence of the same bacteria on arterial stiffness. NCT03900338.

Chronic lymphocytic leukemia patients with chromosome 6q deletion as the sole cytogenetic abnormality display a high frequency of RPS15 mutations and have a poor prognosis

2026-05-20T00:03:05Z

[EN]Chronic lymphocytic leukemia (CLL) is a clinically heterogeneous disease, with survival times ranging from months to decades, reflecting a great biological diversity. Classical cytogenetical models allow to classify patients in different risk subgroups according to the presence of certain chromosomal aberrations, being the most common the 13q deletion (del(13q)), 17p deletion (del(17p)), 11q deletion (del(11q)), and trisomy 12 (+12).1 By contrast, other less frequent cytogenetic alterations, including 6q deletion (del(6q)), affects a lower but not insignificant percentage of patients (5%). Several studies have suggested an association of del(6q) with inferior outcomes, allocating these CLL cases in an intermediate-risk category,2, 3 although other studies have shown no difference in outcomes.4 The recurrence of del(6q) in other B-cell malignancies strongly suggests that this region contains unidentified tumor-suppressor gene(s). Nevertheless, CLL patients harboring del(6q) remain poorly characterized at the molecular level, partly due to the low incidence of cases, the lack of a FISH-based routinely assessment of del(6q), and the co-occurrence with other abnormalities that masks their clinical and biological significance. Here, we comprehensively characterize for the first time the genetic landscape of CLL patients with del(6q) identified by karyotyping, since we believe that a mutational screening could allow for refinement in predicting overall survival and time to first treatment, as well as provide novel insights into del(6q) CLL pathobiology.

Lifestyles, arterial aging, and its relationship with the intestinal and oral microbiota (MIVAS III study): a research protocol for a cross-sectional multicenter study

2026-05-19T00:01:27Z

[EN]The microbiota is increasingly recognized as a significant factor in the pathophysiology of many diseases, including cardiometabolic diseases, with lifestyles probably exerting the greatest influence on the composition of the human microbiome. The main objectives of the study are to analyze the association of lifestyles (diet, physical activity, tobacco, and alcohol) with the gut and oral microbiota, arterial aging, and cognitive function in subjects without cardiovascular disease in the Iberian Peninsula. In addition, the study will examine the mediating role of the microbiome in mediating the association between lifestyles and arterial aging as well as cognitive function. MIVAS III is a multicenter cross-sectional study that will take place in the Iberian Peninsula. One thousand subjects aged between 45 and 74 years without cardiovascular disease will be selected. The main variables are demographic information, anthropometric measurements, and habits (tobacco and alcohol). Dietary patterns will be assessed using a frequency consumption questionnaire (FFQ) and the Mediterranean diet adherence questionnaire. Physical activity levels will be evaluated using the International Physical Activity Questionnaire (IPAQ), Marshall Questionnaire, and an Accelerometer (Actigraph). Body composition will be measured using the Inbody 230 impedance meter. Arterial aging will be assessed through various means, including measuring medium intimate carotid thickness using the Sonosite Micromax, conducting analysis with pulse wave velocity (PWA), and measuring pulse wave velocity (cf-PWV) using the Sphygmocor System. Additional cardiovascular indicators such as Cardio Ankle Vascular Index (CAVI), ba-PWV, and ankle-brachial index (Vasera VS-2000®) will also be examined. The study will analyze the intestinal microbiota using the OMNIgene GUT kit (OMR-200) and profile the microbiome through massive sequencing of the 16S rRNA gene. Linear discriminant analysis (LDA), effect size (LEfSe), and compositional analysis, such as ANCOM-BC, will be used to identify differentially abundant taxa between groups. After rarefying the samples, further analyses will be conducted using MicrobiomeAnalyst and R v.4.2.1 software. These analyses will include various aspects, such as assessing α and β diversity, conducting abundance profiling, and performing clustering analysis. Lifestyle acts as a modifier of microbiota composition. However, there are no conclusive results demonstrating the mediating effect of the microbiota in the relationship between lifestyles and cardiovascular diseases. Understanding this relationship may facilitate the implementation of strategies for improving population health by modifying the gut and oral microbiota. clinicaltrials.gov/ct2/show/NCT04924907, ClinicalTrials.gov, identifier: NCT04924907. Registered on 21 April 2021.

Novel variants in GALE cause syndromic macrothrombocytopenia by disrupting glycosylation and thrombopoiesis

2026-05-15T00:01:54Z

[EN]Glycosylation is recognized as a key process for proper megakaryopoiesis and platelet formation. The enzyme uridine diphosphate (UDP)-galactose-4-epimerase, encoded by GALE, is involved in galactose metabolism and protein glycosylation. Here, we studied 3 patients from 2 unrelated families who showed lifelong severe thrombocytopenia, bleeding diathesis, mental retardation, mitral valve prolapse, and jaundice. Whole-exome sequencing revealed 4 variants that affect GALE, 3 of those previously unreported (Pedigree A, p.Lys78ValfsX32 and p.Thr150Met; Pedigree B, p.Val128Met; and p.Leu223Pro). Platelet phenotype analysis showed giant and/or grey platelets, impaired platelet aggregation, and severely reduced alpha and dense granule secretion. Enzymatic activity of the UDP-galactose-4-epimerase enzyme was severely decreased in all patients. Immunoblotting of platelet lysates revealed reduced GALE protein levels, a significant decrease in N-acetyl-lactosamine (LacNAc), showing a hypoglycosylation pattern, reduced surface expression of gylcoprotein Ibα-IX-V (GPIbα-IX-V) complex and mature β1 integrin, and increased apoptosis. In vitro studies performed with patients-derived megakaryocytes showed normal ploidy and maturation but decreased proplatelet formation because of the impaired glycosylation of the GPIbα and β1 integrin, and reduced externalization to megakaryocyte and platelet membranes. Altered distribution of filamin A and actin and delocalization of the von Willebrand factor were also shown. Overall, this study expands our knowledge of GALE-related thrombocytopenia and emphasizes the critical role of GALE in the physiological glycosylation of key proteins involved in platelet production and function.

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

2026-05-15T00:01:34Z

[EN]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 (34.7%) patients at frequencies ranging from 2.3-9.8% with mutations in NOTCH1 being the most frequent. In both univariate and multivariate analyses, mutations in all genes except MYD88 were associated with a significantly shorter TTFT. In multivariate analysis of Binet stage A patients, performed separately for IGHV-mutated (M-CLL) and unmutated CLL (U-CLL), a different spectrum of gene alterations independently predicted short TTFT within the two subgroups. While SF3B1 and XPO1 mutations were independent prognostic variables in both U-CLL and M-CLL, TP53, BIRC3 and EGR2 aberrations were significant predictors only in U-CLL, and NOTCH1 and NFKBIE only in M-CLL. Our findings underscore the need for a compartmentalized approach to identify high-risk patients, particularly among M-CLL patients, with potential implications for stratified management.

Building a healthcare alliance for resourceful medicine offensive against neoplasms in hematology added value framework for hematologic malignancies: a comparative analysis of existing tools

2026-05-15T00:01:29Z

[EN]The Innovative Medicines Initiative-funded, multistakeholders project Healthcare Alliance for Resourceful Medicine Offensive Against Neoplasms in Hematology (HARMONY) created a task force involving patient organizations, medical associations, pharmaceutical companies, and health technology assessment/regulator agencies' representatives to evaluate the suitability of previously established value frameworks (VFs) for assessing the clinical and societal impact of new interventions for hematologic malignancies (HMs). Since the HARMONY stakeholders identified the inclusion of patients' points of view on evaluating VFs as a priority, surveys were conducted with the patient organizations active in HMs and part of the HARMONY network, together with key opinion leaders, pharmaceutical companies, and regulators, to establish which outcomes were important for each HM. Next, to evaluate VFs against the sources of information taken into account (randomized clinical trials, registries, real-world data), structured questionnaires were created and filled by HARMONY health professionals to specify preferred data sources per malignancy. Finally, a framework evaluation module was built to analyze existing clinical VFs (American Society of Clinical Oncology, European Society of Medical Oncology, Magnitude of Clinical Benefit Scale, Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen, Institute for Clinical and Economic Review, National Comprehensive Cancer Network Evidence Blocks, and patient-perspective VF). The comparative analysis describes challenges and opportunities for the use of each framework in the context of HMs and drafts possible lines of action for creating or integrating a more specific, patient-focused clinical VF for HMs. None of the frameworks meets the HARMONY goals for a tool that applies to HMs and assesses in a transparent, reproducible, and systematic way the therapeutic value of innovative health technologies versus available alternatives, taking a patient-centered approach and using real-world evidence.

Clinical, biological, and prognostic implications of SF3B1 co-occurrence mutations in very low/low- and intermediate-risk MDS patients

2026-05-15T00:01:31Z

[EN]SF3B1 is a highly mutated gene in myelodysplastic syndrome (MDS) patients, related to a specific subtype and parameters of good prognosis in MDS without excess blasts. More than 40% of MDS patients carry at least two myeloid-related gene mutations but little is known about the impact of concurrent mutations on the outcome of MDS patients. In applying next-generation sequencing (NGS) with a 117 myeloid gene custom panel, we analyzed the co-occurrence of SF3B1 with other mutations to reveal their clinical, biological, and prognostic implications in very low/low- and intermediate-risk MDS patients. Mutations in addition to those of SF3B1 were present in 80.4% of patients (median of 2 additional mutations/patient, range 0-5). The most frequently mutated genes were as follows: TET2 (39.2%), DNMT3A (25.5%), SRSF2 (10.8%), CDH23 (5.9%), and ASXL1, CUX1, and KMT2D (4.9% each). The presence of at least two mutations concomitant with that of SF3B1 had an adverse impact on survival compared with those with the SF3B1 mutation and fewer than two additional mutations (median of 54 vs. 87 months, respectively: p = 0.007). The co-occurrence of SF3B1 mutations with specific genes is also linked to a dismal prognosis: SRSF2 mutations were associated with shorter overall survival (OS) than SRSF2wt (median, 27 vs. 75 months, respectively; p = 0.001), concomitant IDH2 mutations (median OS, 11 [mut] vs. 75 [wt] months; p = 0.001), BCOR mutations (median OS, 11 [mut] vs. 71 [wt] months; p = 0.036), and NUP98 and STAG2 mutations (median OS, 27 and 11 vs. 71 months, respectively; p = 0.008 and p = 0.002). Mutations in CHIP genes (TET2, DNMT3A) did not significantly affect the clinical features or outcome. Our results suggest that a more comprehensive NGS study in low-risk MDS SF3B1mut patients is essential for a better prognostic evaluation.

Clonal heterogeneity and rates of specific chromosome gains are risk predictors in childhood high-hyperdiploid B-cell acute lymphoblastic leukemia

2026-05-15T00:01:25Z

[EN]B-cell acute lymphoblastic leukemia (B-ALL) is the commonest childhood cancer. High hyperdiploidy (HHD) identifies the most frequent cytogenetic subgroup in childhood B-ALL. Although hyperdiploidy represents an important prognostic factor in childhood B-ALL, the specific chromosome gains with prognostic value in HHD-B-ALL remain controversial, and the current knowledge about the hierarchy of chromosome gains, clonal heterogeneity and chromosomal instability in HHD-B-ALL remains very limited. We applied automated sequential-iFISH coupled with single-cell computational modeling to identify the specific chromosomal gains of the eight typically gained chromosomes in a large cohort of 72 primary diagnostic (DX, n = 62) and matched relapse (REL, n = 10) samples from HHD-B-ALL patients with either favorable or unfavorable clinical outcome in order to characterize the clonal heterogeneity, specific chromosome gains and clonal evolution. Our data show a high degree of clonal heterogeneity and a hierarchical order of chromosome gains in DX samples of HHD-B-ALL. The rates of specific chromosome gains and clonal heterogeneity found in DX samples differ between HHD-B-ALL patients with favorable or unfavorable clinical outcome. In fact, our comprehensive analyses at DX using a computationally defined risk predictor revealed low levels of trisomies +18+10 and low levels of clonal heterogeneity as robust relapse risk factors in minimal residual disease (MRD)-negative childhood HHD-B-ALL patients: relapse-free survival beyond 5 years: 22.1% versus 87.9%, P < 0.0001 and 33.3% versus 80%, P < 0.0001, respectively. Moreover, longitudinal analysis of matched DX-REL HHD-B-ALL samples revealed distinct patterns of clonal evolution at relapse. Our study offers a reliable prognostic sub-stratification of pediatric MRD-negative HHD-B-ALL patients.

Second revision of the international staging system (R2-ISS) for overall survival in multiple myeloma: a european myeloma network (EMN) report within the HARMONY project

2026-05-12T00:01:31Z

[EN]Patients with newly diagnosed multiple myeloma (NDMM) show heterogeneous outcomes, and approximately 60% of them are at intermediate-risk according to the Revised International Staging system (R-ISS), the standard-of-care risk stratification model. Moreover, chromosome 1q gain/amplification (1q+) recently proved to be a poor prognostic factor. In this study, we revised the R-ISS by analyzing the additive value of each single risk feature, including 1q+. The European Myeloma Network, within the HARMONY project, collected individual data from 10,843 patients with NDMM enrolled in 16 clinical trials. An additive scoring system on the basis of top features predicting progression-free survival (PFS) and overall survival (OS) was developed and validated. In the training set (N = 7,072), at a median follow-up of 75 months, ISS, del(17p), lactate dehydrogenase, t(4;14), and 1q+ had the highest impact on PFS and OS. These variables were all simultaneously present in 2,226 patients. A value was assigned to each risk feature according to their OS impact (ISS-III 1.5, ISS-II 1, del(17p) 1, high lactate dehydrogenase 1, and 1q+ 0.5 points). Patients were stratified into four risk groups according to the total additive score: low (Second Revision of the International Staging System [R2-ISS]-I, 19.2%, 0 points), low-intermediate (II, 30.8%, 0.5-1 points), intermediate-high (III, 41.2%, 1.5-2.5 points), high (IV, 8.8%, 3-5 points). Median OS was not reached versus 109.2 versus 68.5 versus 37.9 months, and median PFS was 68 versus 45.5 versus 30.2 versus 19.9 months, respectively. The score was validated in an independent validation set (N = 3,771, of whom 1,214 were with complete data to calculate R2-ISS) maintaining its prognostic value. The R2-ISS is a simple prognostic staging system allowing a better stratification of patients with intermediate-risk NDMM. The additive nature of this score fosters its future implementation with new prognostic variables.

CRISPR/Cas9-directed gene trap constitutes a selection system for corrected BCR/ABL leukemic Cells in CML

2026-05-12T00:01:30Z

[EN]Chronic myeloid leukaemia (CML) is a haematological neoplasm driven by the BCR/ABL fusion oncogene. The monogenic aspect of the disease and the feasibility of ex vivo therapies in haematological disorders make CML an excellent candidate for gene therapy strategies. The ability to abolish any coding sequence by CRISPR-Cas9 nucleases offers a powerful therapeutic opportunity to CML patients. However, a definitive cure can only be achieved when only CRISPR-edited cells are selected. A gene-trapping approach combined with CRISPR technology would be an ideal approach to ensure this. Here, we developed a CRISPR-Trap strategy that efficiently inserts a donor gene trap (SA-CMV-Venus) cassette into the BCR/ABL-specific fusion point in the CML K562 human cell line. The trapping cassette interrupts the oncogene coding sequence and expresses a reporter gene that enables the selection of edited cells. Quantitative mRNA expression analyses showed significantly higher level of expression of the BCR/Venus allele coupled with a drastically lower level of BCR/ABL expression in Venus+ cell fractions. Functional in vitro experiments showed cell proliferation arrest and apoptosis in selected Venus+ cells. Finally, xenograft experiments with the selected Venus+ cells showed a large reduction in tumour growth, thereby demonstrating a therapeutic benefit in vivo. This study represents proof of concept for the therapeutic potential of a CRISPR-Trap system as a novel strategy for gene elimination in haematological neoplasms.

TRAF3 alterations are frequent in del-3'IGH chronic lymphocytic leukemia patients and define a specific subgroup with adverse clinical features

2026-05-12T00:01:27Z

[EN]Interstitial 14q32 deletions involving IGH gene are infrequent events in chronic lymphocytic leukemia (CLL), affecting less than 5% of patients. To date, little is known about their clinical impact and molecular underpinnings, and its mutational landscape is currently unknown. In this work, a total of 871 CLLs were tested for the IGH break-apart probe, and 54 (6.2%) had a 300 kb deletion of 3'IGH (del-3'IGH CLLs), which contributed to a shorter time to first treatment (TFT). The mutational analysis by next-generation sequencing of 317 untreated CLLs (54 del-3'IGH and 263 as the control group) showed high mutational frequencies of NOTCH1 (30%), ATM (20%), genes involved in the RAS signaling pathway (BRAF, KRAS, NRAS, and MAP2K1) (15%), and TRAF3 (13%) within del-3'IGH CLLs. Notably, the incidence of TRAF3 mutations was significantly higher in del-3'IGH CLLs than in the control group (p < .001). Copy number analysis also revealed that TRAF3 loss was highly enriched in CLLs with 14q deletion (p < .001), indicating a complete biallelic inactivation of this gene through deletion and mutation. Interestingly, the presence of mutations in the aforementioned genes negatively refined the prognosis of del-3'IGH CLLs in terms of overall survival (NOTCH1, ATM, and RAS signaling pathway genes) and TFT (TRAF3). Furthermore, TRAF3 biallelic inactivation constituted an independent risk factor for TFT in the entire CLL cohort. Altogether, our work demonstrates the distinct genetic landscape of del-3'IGH CLL with multiple molecular pathways affected, characterized by a TRAF3 biallelic inactivation that contributes to a marked poor outcome in this subgroup of patients.