Extracellular vesicles (EVs) are a new mechanism of cellular communication, by delivering their cargo into target cells to modulate molecular pathways. EV-mediated crosstalk contributes to tumor survival and resistance to cellular stress. However, the role of EVs in B-cell Acute Lymphoblastic Leukaemia (B-ALL) awaits to be thoroughly investigated. We recently published that ActivinA increases intracellular calcium levels and promotes actin polymerization in B-ALL cells. These biological processes guide cytoskeleton reorganization, which is a crucial event for EV secretion and internalization. Hence, we investigated the role of EVs in the context of B-ALL and the impact of ActivinA on this phenomenon. We demonstrated that leukemic cells release a higher number of EVs in response to ActivinA treatment, and they can actively uptake EVs released by other B-ALL cells. Under culture-induced stress conditions, EVs coculture promoted cell survival in B-ALL cells in a dose-dependent manner. Direct stimulation of B-ALL cells with ActivinA or with EVs isolated from ActivinA-stimulated cells was even more effective in preventing cell death. This effect can be possibly ascribed to the increase of vesiculation and modifications of EV-associated microRNAs induced by ActivinA. These data demonstrate that ActivinA boosts EV-mediated B-ALL crosstalk, improving leukemia survival in stress conditions.

UNASSIGNED: Pityriasis amiantacea (PA) is a rare presentation characterized by the presence of extensive adherent scaling that tightly encircles and affixes tufts of hairs secondary to inflammatory or infectious dermatoses. However, the occurrence of PA as a consequence of leukaemia cutis has not been previously reported.
UNASSIGNED: A 32-year-old man with B-cell acute lymphoblastic leukaemia (B-ALL) presented with severe scalp scaling and hair loss for 2 months. Examination revealed extensive, tightly adherent scales encircling and binding down hairs, along with haemorrhagic crusts. Skin examination showed nontender, partially blanchable papules forming ill-defined plaques, giving a cobblestone appearance. Trichoscopy revealed white crusts, tufting, and micro-haemorrhages. Scalp biopsy confirmed precursor B-ALL infiltration. He was diagnosed with PA with secondary cutis verticis gyrata due to leukaemia cutis and referred to a haemato-oncologist for further management.
UNASSIGNED: Leukaemia cutis is a rare condition where leukaemia cells infiltrate the skin, often associated with acute myeloid leukaemia and ALL. It can lead to secondary verticis gyrata. The co-occurrence of PA and cutis verticis gyrata is rare and previously unreported, highlighting the need for increased awareness among clinicians.

B-cell acute lymphoblastic leukaemia (B-cell ALL) is a common haematologic cancer in children and adults. About 10 percent of children and 50 percent of adults fail to achieve a histological complete remission or subsequently relapse despite current anti-leukaemia drug therapies and/or haematopoietic cell transplants. Several new immune therapies including monoclonal antibodies and chimeric antigen receptor (CAR)-T-cells are proved safe and effective in this setting. We review data on US Food and Drug Administration (FDA)-approved immune therapies for B-cell ALL in children and adults including blinatumomab, inotuzumab ozogamicin, tisagenlecleucel, and brexucabtagene autoleucel. We also summarize pharmaco-dynamics, pharmaco-kinetics, and pharmaco-economics of these interventions.

IGH::DUX4 is frequently observed in 4% B-cell acute lymphoblastic leukaemia patients. Regarding the IGH::DUX4-driven transactivation and alternative splicing, which are the main reasons behind this acute leukaemia outbreak, it remains unclear how transcriptional cofactors contribute to this oncogenic process. Further investigation is required to elucidate their specific role in leukaemogenesis.
In order to investigate the cofactors of IGH::DUX4, integrated mining of Chromatin immunoprecipitation (ChIP)-sequencing and RNA-sequencing of leukaemia cells and patient samples were conducted. Furthermore, to elucidate the synergistic interaction between transcription factor 12 (TCF12) and IGH::DUX4, knockdown and knockout experiment, mammalian two-hybridisation assay, co-immunoprecipitation and in situ proximity ligation assays were carried out. Additionally, to further investigate the direct interaction between TCF12 and IGH::DUX4, AI-based structural simulations were utilised. Finally, to validate the synergistic role of TCF12 in promoting IGH::DUX4 leukaemia, cell proliferation, apoptosis and drug sensitivity experiments were performed.
In this study, we observed that the IGH::DUX4 target gene TCF12 might be an important cofactor/helper for this oncogenic driver. The co-expression of IGH::DUX4 and TCF12 resulted in enhanced DUX4-driven transactivation. Supportively, knockdown and knockout of TCF12 significantly reduced expression of IGH::DUX4-driven target genes in leukaemia REH (a precursor B-cell leukaemia cell line) and NALM-6 cells (a precursor B-cell leukaemia cell line). Consistently, in TCF12 knockout cells, the expression of structure-based TCF12 mutant, but not wild-type TCF12, failed to restore the TCF12-IGH::DUX4 crosstalk and the synergistic transactivation. More importantly, the breakdown in TCF12-IGH::DUX4 cooperation impaired IGH::DUX4-driven leukaemia cell survival, caused sensitivity to the chemotherapy.
Altogether, these results helped to define a previously unrecognised TCF12-mediated positive self-feedback regulatory mechanism in IGH::DUX4 leukaemia, which holds the potential to function as a pivotal drug target for the management of this particular form of leukaemia.
Transcription factor 12 (TCF12) is a new novel cofactor in IGH::DUX4 transcriptional complexes/machinery. TCF12 mediates a positive self-feedback regulatory mechanism in IGH::DUX4-driven oncogenic transaction. IGH::DUX4-TCF12 structure/cooperation might represent a potent target/direction in future drug design against B-cell acute lymphoblastic leukaemia.

This PASS-ALL study was designed to explore the effect of paediatric-inspired versus adult chemotherapy regimens on survival of adolescents and young adults (AYA) with high-risk Philadelphia chromosome-negative B-cell acute lymphoblastic leukaemia (HR PH-ve B-cell ALL) eligible for allogeneic haematopoietic stem cell transplantation (allo-HSCT). The PASS-ALL study is a multicentre, observational cohort study, and 143 patients with HR B-cell PH-ve ALL were enrolled from five centres-77 patients allocated in the paediatric-inspired cohort and 66 in the adult cohort with comparable baseline characteristics. Of the 143 patients, 128 cases underwent allo-HSCT. Three-year leukaemia-free survival (LFS) in the paediatric-inspired cohort was 72.2% (95% CI 60.8%-83.6%) compared with 44.6% (95% CI 31.9%-57.3%; p = 0.001). Furthermore, time-to-positive minimal residual disease (TTP-MRD) post-HSCT was marked different, 3-year cumulative incidence of relapse was 25.9% (95% CI 15.8%-37.2%) in paediatric cohort and 45.4% (95% CI 40.0%-57.9%) in adult cohort (p = 0.026). Finally, the 3-year OS rate was 75.3% (95% CI 64.9%-85.7%) for the paediatric-inspired cohort and 64.1% (95% CI 51.8%-76.4%) for the adult cohort (p = 0.074). On a multivariate analysis, paediatric-inspired regimen is a predictive factor for LFS (HR = 2.540, 95% CI 1.327-4.862, p = 0.005). Collectively, our data suggest that paediatric-inspired chemotherapy pre-HSCT results in deeper and durable MRD response reduces relapse post-HSCT and improves survival in HR B-cell PH-ve ALL patients with allo-HSCT.

B-cell acute lymphoblastic leukaemia (B-ALL) is characterised by diverse genomic alterations, the most frequent being gene fusions detected via transcriptomic analysis (mRNA-seq). Due to its hypervariable nature, gene fusions involving the Immunoglobulin Heavy Chain (IGH) locus can be difficult to detect with standard gene fusion calling algorithms and significant computational resources and analysis times are required. We aimed to optimize a gene fusion calling workflow to achieve best-case sensitivity for IGH gene fusion detection. Using Nextflow, we developed a simplified workflow containing the algorithms FusionCatcher, Arriba, and STAR-Fusion. We analysed samples from 35 patients harbouring IGH fusions (IGH::CRLF2 n = 17, IGH::DUX4 n = 15, IGH::EPOR n = 3) and assessed the detection rates for each caller, before optimizing the parameters to enhance sensitivity for IGH fusions. Initial results showed that FusionCatcher and Arriba outperformed STAR-Fusion (85-89% vs. 29% of IGH fusions reported). We found that extensive filtering in STAR-Fusion hindered IGH reporting. By adjusting specific filtering steps (e.g., read support, fusion fragments per million total reads), we achieved a 94% reporting rate for IGH fusions with STAR-Fusion. This analysis highlights the importance of filtering optimization for IGH gene fusion events, offering alternative workflows for difficult-to-detect high-risk B-ALL subtypes.

OBJECTIVE: L-asparaginase is an essential medicine for childhood ALL. The quality of generic L-asparaginase available in India is a matter of concern. We compared four commonly used generic formulations of L-asparaginase in India.
METHODS: We conducted a prospective, open-label, randomised trial of four generic formulations of asparaginase for the treatment of patients with newly diagnosed intermediate-risk B-ALL. Patients were randomly assigned in a 1:1:1:1 ratio to receive generic asparaginase at a dose of at 10,000 IU/m 2 on days 9, 12, 15, and 18 of a 35-day cycle (Induction treatment). The primary end points were to determine the difference in the asparaginase activity and asparagine depletion. Historical patients who received L-asparaginase Medac (innovator) served as controls.
RESULTS: A total of 48 patients underwent randomization; 12 patients each in the four arms. Failure to achieve predefined activity threshold of 100 IU/L was observed in 9/40 samples of Generic A (22·5%), 23/40 of Generic B (57·5%), and 43/44 (98%) each of Generic C and D. All 27 samples from seven historical patients who were administered Medac had activity > 100 IU/L. The average activity was significantly higher for Genericm A, 154 (70·3, 285·4) IU/L followed by Generic B 84·5(44·2, 289·1) IU/L, Generic C 45(14·4, 58·4) IU/L, and Generic D 20·4(13, 35) IU/L. Only 6 patients had asparaginase activity > 100 IU/L on each of the four occasions (Generic A = 5; Generic B = 1), and none of them developed Anti-Asparaginase Antibodies (AAA). On the other hand, AAA was observed in 12/36 patients who had at least one level < 100 IU/L (P < 0·05): Generic A 3/5, Generic B = 3/9, Generic D (4/11), and Generic C (5/11).
CONCLUSIONS: Generic A and B had better trough asparaginase activity compared to Generic D and C. Overall, generic formulations had lower asparaginase activity which raises serious clinical concerns regarding their quality. Until strict regulatory enforcement improves the quality of these generics, dose adaptive approaches coupled with therapeutic drug monitoring need to be considered.

Acute lymphoblastic leukaemia (ALL) in adults is a rare and difficult-to-treat cancer that is characterised by excess lymphoblasts in the bone marrow. Although many patients achieve remission with chemotherapy, relapse rates are high and the associated impact on survival devastating. Most patients receive chemotherapy and for those whose overall fitness supports it, the most effective treatment to date is allogeneic stem cell transplant that can improve overall survival rates in part due to a \'graft-versus-leukaemia\' effect. However, due to the rarity of this disease, and the availability of mature B-cell antigens on the cell surface, few new cancer antigens have been identified in adult B-ALL that could act as targets to remove residual disease in first remission or provide alternative targets for escape variants if and when current immunotherapy strategies fail. We have used RT-PCR analysis, literature searches, antibody-specific profiling and gene expression microarray analysis to identify and prioritise antigens as novel targets for the treatment of adult B-ALL.

Refinement of risk stratification in Philadelphia chromosome (Ph)-negative B-cell acute lymphoblastic leukaemia (ALL) might aid the identification of patients who are likely to relapse. Abnormal S100 calcium binding protein A16 (S100A16) has been implicated in various cancers, but its function remains unclear. We found S100A16 transcript levels were higher in 130 adults with newly-diagnosed Ph-negative B-cell ALL compared with 33 healthy controls. In 115 of 130 patients who achieved first complete remission, those with high S100A16 transcript levels displayed a lower 3-year cumulative incidence of relapse (CIR; 34% [21, 47%] vs. 40% [48, 72%]; P = 0·012) and higher 3-year relapse-free survival (RFS; 65% [53, 78%] vs. 35% [23, 46%]; P = 0·012), especially when receiving chemotherapy only. In multivariate analysis a low S100A16 transcript level was independently-associated with a higher CIR (Hazard ratio [HR] = 3·74 [1·01-13·82]; P = 0·048) and inferior RFS (HR = 5·78 [1·91, 17·84]; P < 0·001). Function analysis indicated that knockdown of S100A16 promoted proliferation and anti-apoptosis and reduced chemosensitivity. S100A16 over-expression revealed an opposite trend, especially in a xeno-transplant mouse model. Western blotting analysis showed upregulation of PI3K/AKT and ERK1/2 in S100A16-knockdown and S100A16-overexpression B-cell ALL cell lines respectively. Inhibition assays suggested these two signalling pathways participated in the S100A16-mediated proliferation and survival effects in B-cell ALL cell lines. Trial Registration: Registered in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940]; http://www.chictr.org.cn.

The aim of this study was to characterize the effect of inotuzumab ozogamicin on QT interval in patients with B-cell malignancies.
Data were pooled from three clinical studies including 250 patients (n = 2743) who received inotuzumab ozogamicin monotherapy. Patients with relapsed/refractory acute lymphoblastic leukaemia (NCT01564784 and NCT01363297) received 1.8 mg m-2 per cycle in divided doses (mean Cmax 371 ng ml-1 ; considered therapeutic) and patients with relapsed/refractory non-Hodgkin lymphoma (NCT00868608) received 1.8 mg m-2 per cycle as a single dose (mean Cmax 569 ng ml-1 ; considered supratherapeutic). Triplicate 12-lead electrocardiograms were performed at baseline and predefined time points postdose with paired pharmacokinetic collections. The exposure-response relationship between corrected QT interval (QTc: QT interval corrected using population-specific formula [QTcS] or QT interval corrected using Fridericia\'s formula [QTcF]) and inotuzumab ozogamicin concentration was characterized using a linear mixed-effects model, and simulations were performed using the final validated model. Full model development involved testing for covariates that may account for part of the identified variability.
QTc intervals had a small but positive correlation with inotuzumab ozogamicin concentration. Based on 1000 simulations, median (upper 95% CI) QTcS and QTcF changes from baseline were <10 ms at both therapeutic (2.70 ms [5.40 ms] and 2.53 ms [4.92 ms], respectively) and supratherapeutic (4.14 ms [8.28 ms] and 3.87 ms [7.54 ms], respectively) concentrations.
Inotuzumab ozogamicin (1.8 mg m-2 per cycle) is not predicted to pose a clinically significant safety risk for QT prolongation in patients with acute lymphoblastic leukaemia or non-Hodgkin lymphoma.