Different Levels of Therapeutic Strategies to Recover the Microbiome to Prevent/Delay Acute Lymphoblastic Leukemia (ALL) or Arrest Its Progression in Children

Changes in the components, variety, metabolism, and products of microbiomes, particularly of the gut microbiome (GM), have been revealed to be closely associated with the onset and progression of numerous human illnesses, including hematological neoplasms. Among the latter pathologies, there is acute lymphoblastic leukemia (ALL), the most widespread malignant neoplasm in pediatric subjects. Accordingly, ALL cases present a typical dysfunctional GM during all its clinical stages and resulting inflammation, which contributes to its progression, altered response to therapy, and possible relapses. Children with ALL have GM with characteristic variations in composition, variety, and functions, and such alterations may influence and predict the complications and prognosis of ALL after chemotherapy treatment or stem cell hematopoietic transplants. In addition, growing evidence also reports the ability of GM to influence the formation, growth, and roles of the newborn's hematopoietic system through the process of developmental programming during fetal life as well as its susceptibility to the onset of onco-hematological pathologies, namely ALL. Here, we suggest some therapeutic strategies that can be applied at two levels of intervention to recover the microbiome and consequently prevent/delay ALL or arrest its progression.

IKZF3 polymorphisms contribute to the increased risk of acute lymphoblastic leukemia in children

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common cancer in children. IKZF3 (IKAROS family zinc finger 3) is a hematopoietic-specific transcription factor, and it has been validated that it is involved in leukemia. However, the role of IKZF3 single-nucleotide polymorphisms (SNPs) remains unclear. In this case-control study, the authors investigated the association of IKZF3 SNPs with ALL in children.

METHODS

Six IKZF3 reference SNPs (rs9635726, rs2060941, rs907092, rs12946510, rs1453559, and rs62066988) were genotyped in 692 patients who had ALL (cases) and in 926 controls. The associations between IKZF3 polymorphisms and ALL risk were determined using odds ratios (ORs) and 95% confidence intervals (CIs). The associations of rs9635726 and rs2060941 with the risk of ALL were further estimated by using false-positive report probability (FPRP) analysis. Functional analysis in silico was performed to evaluate the probability that rs9635726 and rs2060941 might influence the regulation of IKZF3.

RESULTS

The authors observed that rs9635726C>T (adjusted OR, 1.49; 95% CI, 1.06-2.11; p = .023) and rs2060941G>T (adjusted OR, 1.51; 95% CI, 1.24-1.84; p = .001) were related to and increased risk of ALL in the recessive and dominant models, respectively. Furthermore, the associations of both rs9635726 (FPRP = .177) and rs2060941 (FPRP < .001) with ALL were noteworthy in the FPRP analysis. Functional analysis indicated that rs9635726 and rs2060941 might repress the transcription of IKZF3 by disrupting its binding to MLLT1, TAF1, POLR2A, and/or RAD21.

CONCLUSIONS

This study revealed that IKZF3 polymorphisms were associated with increased ALL susceptibility in children and might influence the expression of IKZF3 by disrupting its binding to MLLT1, TAF1, POLR2A, and/or RAD21. IKZF3 polymorphisms were suggested as a biomarker for childhood ALL.

Simulating neuronal development: exploring potential mechanisms for central nervous system metastasis in acute lymphoblastic leukemia

Background

Acute lymphoblastic leukemia (ALL) is prone to metastasize to the central nervous system (CNS), which is an important cause of poor treatment outcomes and unfavorable prognosis. However, the pathogenesis of CNS metastasis of ALL cells has not been fully illuminated. Recent reports have shed some light on the correlation between neural mechanisms and ALL CNS metastasis. These progressions prompt us to study the relationship between ALL central nervous system metastasis and neuronal development, exploring potential biomarkers and therapeutic targets of CNS metastasis.

Materials and methods

ALL central nervous system metastasis- and neuronal development-related differentially expressed genes (DEGs) were identified by analyzing gene expression datasets GSE60926 and GSE13715. Target prediction and network analysis methods were applied to assess protein-protein interaction networks. Gene Ontology (GO) terms and pathway enrichment for DEGs were assessed. Co-expressed differentially expressed genes (co-DEGs) coupled with corresponding predicted microRNAs (miRNAs) were studied as well. Reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry were employed for the validation of key co-DEGs in primary ALL cells. Furthermore, ALL cells were treated with a vascular endothelial growth factor (VEGF) inhibitor to block neuronal development and assess changes in the co-DEGs.

Results

We identified 216, 208, and 204 DEGs in ALL CNS metastasis specimens and neuronal development samples (GSE60926 and GSE13715). CD2, CD3G, CD3D, and LCK may be implicated in ALL CNS metastasis. LAMB1, MATN3, IGFBP3, LGALS1, and NEUROD1 may be associated with neuronal development. Specifically, four co-DEGs (LGALS1, TMEM71, SHISA2, and S100A11) may link ALL central nervous system metastasis and neuronal development process. The miRNAs for each co-DEG could be potential biomarkers or therapeutic targets for ALL central nervous system metastasis, especially hsa-miR-22-3p, hsa-miR-548t-5p, and hsa-miR-6134. Additionally, four co-DEGs (LGALS1, TMEM71, SHISA2, and S100A11) were validated in CNS-infiltrated ALL cells. The VEGF inhibitor demonstrated a suppressive effect on mRNA and protein expression of key co-DEGs.

Conclusion

The bioinformatic survey and key gene validation suggest a possible correlation between ALL CNS metastasis and the neuronal development process. Simulating the neuronal development process might be a possible strategy for CNS metastasis in ALL. LGALS1, TMEM71, SHISA2, and S100A11 genes are promising and novel biomarkers and targets in ALL CNS metastasis.

Childhood acute lymphoblastic leukemia survival and spatial analysis of socio-environmental risks in Mexico

Background

Acute lymphoblastic leukemia (ALL) etiology remains largely unknown; incidence patterns by age, sex, and geographical distribution suggest a potential environmental role.

Aim

To identify ALL clusters from four contrasting urban areas of Mexico and to characterize the sources of environmental carcinogens.

Methods

Hospital-based ALL cases (n = 443) diagnosed in children <19 years old from the Metropolitan Zones of Merida and San Luis Potosi, the State of Mexico, and Tijuana were analyzed (2015-2020). ALL cases were coded according to the International Classification of Diseases for Oncology. ALL clusters were identified by Kernel Density, and excess risk was estimated. Data of particulate matter ≤2.5 µm (PM2.5) concentrations measured by community-monitoring stations were analyzed. Geocoded datasets of benzene, polycyclic aromatic hydrocarbons, and PM2.5 sources were analyzed to characterize patterns of exposure in ALL clusters.

Results

The survival rate for ALL ranged from 61.5% to 78.6%. Seven ALL clusters with excess risk (RR 1.4-2.3, p < 0.05) were identified. The carcinogen sources included artisanal brick kilns, gas stations, cement works, carpentry, paint, and chemical manufacturing establishments. PM2.5 levels ranged from 15 µg/m3 to 37 µg/m3 among study areas.

Conclusion

ALL clusters were identified at the community level; the excess risk could be explained by small-scale carcinogen sources. The levels of PM2.5 in outdoor air ranged from 3 to 6 times above the World Health Organization (WHO) air quality guidelines. Healthcare providers must raise awareness of the increased risk of ALL in children living near sources of environmental carcinogens; cancer control and prevention strategies must be steered from a multi-sectoral and multi-action perspective to protect children's health.

Ruxolitinib inhibits the proliferation and induces the apoptosis of MLL-r ALL cells through inactivating JAK/STAT signaling pathway

Background

The childhood patients with mixed-lineage leukemia rearrangement (MLL-r) gene have worse outcome than non-MLL, and thus often treated with high-risk chemotherapy regimens, so targeted therapy is important for this type of leukemia. This purpose of study was to explore the effects of ruxolitinib on the proliferation, apoptosis, and cell cycle of Nalm-6 cells.

Methods

In this study, human acute lymphoblastic leukemia (ALL) cell line Nalm-6 was used as the research object. By constructing an MLL overexpression vector to transfect Nalm-6 cells, exogenous JAK2/STAT3 signal pathway inhibitor ruxolitinib was applied to observe the proliferation, apoptosis, and cell cycle changes of the transfected Nalm-6 cells. Western blot was performed to determine the proteins (MLL-BP, JAK, STAT) involved in the mechanism of action of MLL-r leukemia. CCK8 assay and flow cytometry (FCM) were used for testing the proliferation and apoptosis among MLL-BP transfected Nalm-6 cells.

Results

Firstly, we determine the IC50 of ruxolitinib on Nalm-6 cells. Secondly, FCM and CCK8 showed that ruxolitinib dosedependentlyinhibits proliferation of Nalm-6 cells by blocking the cell cycle at G₀/G₁ phase. In addition, FCM showed that ruxolitinib promoted the apoptosis of MLL-BP transfected Nalm-6 cells. Mechanistically, ruxolitinib inactivated JAK/STAT signaling pathway in MLL-BP transfected Nalm-6 cells, mediating ruxolitinib's inhibition of cell proliferation, and inducing apoptosis. Finally, ruxolitinib significantly inhibited the proliferation of MLL-r ALL cells and promoted their apoptosis.

Conclusions

These data provide compelling evidence that ruxolitinib is a promising agent against MLL-r leukemia cell line. However, it needs going through multiple more steps to confirm before it can be an option in clinical practice.

Bone Remodeling Markers in Children with Acute Lymphoblastic Leukemia after Intensive Chemotherapy: The Screenshot of a Biochemical Signature

PURPOSE

to investigate the effects of intensive chemotherapy and glucocorticoid (GC) treatment on bone remodeling markers in children with acute lymphoblastic leukemia (ALL).

METHODS

A cross-sectional study was carried out in 39 ALL children (aged 7.64 ± 4.47) and 49 controls (aged 8.7 ± 4.7 years). Osteoprotegerin (OPG), receptor activator of NF-κB ligand (RANKL), osteocalcin (OC), C-terminal telopeptide of type I collagen (CTX), bone alkaline phosphatase (bALP), tartrate-resistant acid phosphatase 5b (TRACP5b), procollagen type I N-terminal propeptide (P1NP), Dickkopf-1 (DKK-1), and sclerostin were assessed. Statistical analysis was conducted using the principal component analysis (PCA) to study patterns of associations in bone markers.

RESULTS

ALL patients showed significantly higher OPG, RANKL, OC, CTX, and TRACP5b than the controls (p ≤ 0.02). Considering ALL group, we found a strong positive correlation among OC, TRACP5b, P1NP, CTX, and PTH (r = 0.43-0.69; p < 0.001); between CTX and P1NP (r = 0.5; p = 0.001); and between P1NP and TRAcP (r = 0.63; p < 0.001). The PCA revealed OC, CTX, and P1NP as the main markers explaining the variability of the ALL cohort.

CONCLUSIONS

Children with ALL showed a signature of bone resorption. The assessment of bone biomarkers could help identify ALL individuals who are most at risk of developing bone damage and who need preventive interventions.

The Prognostic Effect of CDKN2A/2B Gene Deletions in Pediatric Acute Lymphoblastic Leukemia (ALL): Independent Prognostic Significance in BFM-Based Protocols

One of the most frequent genes affected in pediatric ALL is the CDKN2A/2B gene, acting as a secondary cooperating event and playing an important role in cell-cycle regulation and chemosensitivity. Despite its inclusion in combined CNA (copy-number alterations) classifiers, like the IKZF1plus entity and the UKALL CNA profile, the prognostic impact of the individual gene deletions outside the context of a combined CNA evaluation remains controversial. Addressing the CDKN2A/2B deletions' additive prognostic effect in current risk-stratification algorithms, we present a retrospective study of a Greek pediatric ALL cohort comprising 247 patients studied over a 24-year period (2000-2023). Herein, we provide insight regarding the correlation with disease features, MRD clearance, and independent prognostic significance for this ALL cohort treated with contemporary BFM-based treatment protocols. Within an extended follow-up time of 135 months, the presence of the CDKN2A/2B deletions (biallelic or monoallelic) was associated with inferior EFS rates (65.1% compared to 91.8% for the gene non-deleted subgroup, p < 0.001), with the relapse rate accounting for 22.2% and 5.9%, respectively (p < 0.001). The presence of the biallelic deletion was associated with the worst outcomes (EFS 57.2% vs. 89.6% in the case of any other status, monoallelic or non-deleted, p < 0.001). Survival differences were demonstrated for B-ALL cases (EFS 65.3% vs. 93.6% for the non-deleted B-ALL subgroup, p < 0.001), but the prognostic effect was not statistically significant within the T-ALL cohort (EFS 64.3 vs. 69.2, p = 0.947). The presence of the CDKN2A/2B deletions clearly correlated with inferior outcomes within all protocol-defined risk groups (standard risk (SR): EFS 66.7% vs. 100%, p < 0.001, intermediate risk (IR): EFS 77.1% vs. 97.9%, p < 0.001, high risk (HR): EFS 42.1% vs. 70.5% p < 0.001 for deleted vs non-deleted cases in each patient risk group); additionally, in this study, the presence of the deletion differentiated prognosis within both MRD-positive and -negative subgroups on days 15 and 33 of induction. In multivariate analysis, the presence of the CDKN2A/2B deletions was the most important prognostic factor for relapse and overall survival, yielding a hazard ratio of 5.2 (95% confidence interval: 2.59-10.41, p < 0.001) and 5.96 (95% confidence interval: 2.97-11.95, p < 0.001), respectively, designating the alteration's independent prognostic significance in the context of modern risk stratification. The results of our study demonstrate that the presence of the CDKN2A/2B deletions can further stratify all existing risk groups, identifying patient subgroups with different outcomes. The above biallelic deletions could be incorporated into future risk-stratification algorithms, refining MRD-based stratification. In the era of targeted therapies, future prospective controlled clinical trials will further explore the possible use of cyclin-dependent kinase inhibitors (CDKIs) in CDKN2A/2B-affected ALL pediatric subgroups.

Translational advances in the treatment of childhood acute lymphoblastic leukemia: narrative review of current and emerging molecular and immunotherapies

Background and Objective

Acute lymphoblastic leukemia (ALL) is the most common hematologic malignancy of lymphoid origin in children. The prognosis for newly diagnosed ALL in the pediatric population is generally favorable, with a 5-year overall survival rate of more than 90%. Though conventional therapy has led to meaningful improvements in cure rates for new-onset pediatric ALL, one-third of patients still experience a relapse or refractory disease, contributing to a significant cause of pediatric cancer-related mortality.

Methods

An extensive literature review was undertaken via various databases of medical literature, focusing on both results of larger clinical trials, but also with evaluation of recent abstract publications at large hematologic conferences.

Key Content and Findings

Remission is achievable in most of these patients by re-induction with currently available therapies, but the long-term overall survival rate is deemed suboptimal and remains a therapeutic challenge. As part of never-ceasing efforts to improve pediatric ALL outcomes, newer modalities, including targeted molecular therapies as well as immunotherapy, and chimeric antigen receptor (CAR) T-cell therapy, are currently being employed to increase treatment effectiveness as well as lessen the side effects from conventional chemotherapy. These approaches explore the use of early genome-based disease characterization and medications developed against actionable molecular targets.

Conclusions

Additional clinical research is nonetheless required to learn more about the potentially harmful effects of targeted therapies and investigate the possibility of these agents replacing or decreasing the use of conventional chemotherapy in treating pediatric ALL.

Spontaneous remission of acute lymphoblastic leukemia: A series of nine cases and a review of literature

AIMS

To report a series of acute lymphoblastic leukemia (ALL) cases with spontaneous remission and provide presenting clinical and pathologic information and details of clinical course to raise awareness among oncologists and patients.

METHODS

We identified and analyzed nine patients with ALL and spontaneous remission. Review of literature reveals an additional nine previously reported cases with similar clinical course.

RESULTS

All of these patients, ranging in age from 2 to 12 years of age, presented with inciting signs and symptoms of viral or bacterial infection. All of the patients showed varying percentages of lymphoblasts (.2% to 90%) in diagnostic bone marrow biopsy. All B-ALL cases shared a similar blast phenotype on flow cytometry with coexpression of CD19, CD10 and TdT and variable CD20 expression. All nine patients achieved spontaneous remission of their leukemia as confirmed by flow cytometry and/or bone marrow biopsy without chemotherapeutic intervention. Time to remission from presentation ranged from 1 to 8 weeks. After remission, all patients redeveloped ALL, and time from remission to reemergence ranged from 2 to 24 weeks.

CONCLUSION

Our series of cases and cases identified in literature show that ALL diagnosed with modern methods of flow cytometry and molecular analysis will recur within weeks to months from disappearance, usually with cytopenias, which provides a template for oncologic follow-up and testing in these patients.

Analysis of RAS gene mutations in adverse events during first induction chemotherapy in childhood acute lymphoblastic leukemia

BACKGROUND

The rat sarcoma virus (RAS) pathway controls cell proliferation, differentiation, and apoptosis, which have been implicated in the pathogenesis of various hematological malignancies. Prognostic importance of RAS gene mutation, relatively frequently in childhood acute lymphoblastic leukemia (ALL), has been debated. We aimed to study RAS gene mutation profile and prognosis in 93 children with newly diagnosed ALL.

METHODS

We retrospectively analyzed clinical characteristics, treatment, and outcomes of 93 ALL children during first induction chemotherapy in Anhui Provincial Children's Hospital under the Chinese Children's Leukemia Group-acute lymphoblastic leukemia 2018 (CCLG-ALL-2018). All genomic DNA samples were obtained from bone marrow mononuclear cells upon new diagnosis. RAS gene mutation was performed by polymerase chain reaction (PCR). All children were stratified into standard-, medium-, and high-risk groups, and then treated with risk-based regimens according to CCLG-ALL-2018 protocol.

RESULTS

Of 93 ALL children, 26 (27.9%) were positive for RAS mutation, among whom 19 had N-RAS mutation, 8 had K-RAS mutation, and 1 had a double mutation. The ETV6/RUNX1 fusion gene was the most common genetic alteration (n=16, 17.2%). The most common adverse events during first induction chemotherapy were coagulation abnormalities (n=76, 81.7%), followed by fever (n=71, 76.3%) and alanine transaminase (ALT) elevation (n=34, 36.6%). Compared with negative RAS mutation group, the risk of hyperbilirubinemia was significantly reduced in RAS mutation group (P=0.018), and there was no significant difference in any other adverse events. The average duration of agranulocytosis during first induction chemotherapy was 6 days, and the average duration of agranulocytosis in RAS mutation group and RAS negative group was 6 and 5 days, with no significant difference. Multivariate linear regression analysis showed that in RAS mutation group, when body mass index (BMI) exceeded the median value of this ALL population (BMI >15.38), the risk of agranulocytosis was significantly increased (P=0.003).

CONCLUSIONS

Newly diagnosed ALL in children with RAS mutation is less likely to be associated with fusion gene expression. RAS mutation increases the risk of agranulocytosis duration during first induction chemotherapy, lowers BMI and reduces the risk of hyperbilirubinemia in ALL children.

Computer-Aided Diagnosis System for Blood Diseases Using EfficientNet-B3 Based on a Dynamic Learning Algorithm

The immune system's overproduction of white blood cells (WBCs) results in the most common blood cancer, leukemia. It accounts for about 25% of childhood cancers and is one of the primary causes of death worldwide. The most well-known type of leukemia found in the human bone marrow is acute lymphoblastic leukemia (ALL). It is a disease that affects the bone marrow and kills white blood cells. Better treatment and a higher likelihood of survival can be helped by early and precise cancer detection. As a result, doctors can use computer-aided diagnostic (CAD) models to detect early leukemia effectively. In this research, we proposed a classification model based on the EfficientNet-B3 convolutional neural network (CNN) model to distinguish ALL as an automated model that automatically changes the learning rate (LR). We set up a custom LR that compared the loss value and training accuracy at the beginning of each epoch. We evaluated the proposed model on the C-NMC_Leukemia dataset. The dataset was pre-processed with normalization and balancing. The proposed model was evaluated and compared with recent classifiers. The proposed model's average precision, recall, specificity, accuracy, and Disc similarity coefficient (DSC) were 98.29%, 97.83%, 97.82%, 98.31%, and 98.05%, respectively. Moreover, the proposed model was used to examine microscopic images of the blood to identify the malaria parasite. Our proposed model's average precision, recall, specificity, accuracy, and DSC were 97.69%, 97.68%, 97.67%, 97.68%, and 97.68%, respectively. Therefore, the evaluation of the proposed model showed that it is an unrivaled perceptive outcome with tuning as opposed to other ongoing existing models.

Optimizing Molecular Minimal Residual Disease Analysis in Adult Acute Lymphoblastic Leukemia

Minimal/measurable residual disease (MRD) evaluation has resulted in a fundamental instrument to guide patient management in acute lymphoblastic leukemia (ALL). From a methodological standpoint, MRD is defined as any approach aimed at detecting and possibly quantifying residual neoplastic cells beyond the sensitivity level of cytomorphology. The molecular methods to study MRD in ALL are polymerase chain reaction (PCR) amplification-based approaches and are the most standardized techniques. However, there are some limitations, and emerging technologies, such as digital droplet PCR (ddPCR) and next-generation sequencing (NGS), seem to have advantages that could improve MRD analysis in ALL patients. Furthermore, other blood components, namely cell-free DNA (cfDNA), appear promising and are also being investigated for their potential role in monitoring tumor burden and response to treatment in hematologic malignancies. Based on the review of the literature and on our own data, we hereby discuss how emerging molecular technologies are helping to refine the molecular monitoring of MRD in ALL and may help to overcome some of the limitations of standard approaches, providing a benefit for the care of patients.

Customized Deep Learning Classifier for Detection of Acute Lymphoblastic Leukemia Using Blood Smear Images

Acute lymphoblastic leukemia (ALL) is a rare type of blood cancer caused due to the overproduction of lymphocytes by the bone marrow in the human body. It is one of the common types of cancer in children, which has a fair chance of being cured. However, this may even occur in adults, and the chances of a cure are slim if diagnosed at a later stage. To aid in the early detection of this deadly disease, an intelligent method to screen the white blood cells is proposed in this study. The proposed intelligent deep learning algorithm uses the microscopic images of blood smears as the input data. This algorithm is implemented with a convolutional neural network (CNN) to predict the leukemic cells from the healthy blood cells. The custom ALLNET model was trained and tested using the microscopic images available as open-source data. The model training was carried out on Google Collaboratory using the Nvidia Tesla P-100 GPU method. Maximum accuracy of 95.54%, specificity of 95.81%, sensitivity of 95.91%, F1-score of 95.43%, and precision of 96% were obtained by this accurate classifier. The proposed technique may be used during the pre-screening to detect the leukemia cells during complete blood count (CBC) and peripheral blood tests.

Characteristics of white blood cell count in acute lymphoblastic leukemia: A COST LEGEND phenotype-genotype study

BACKGROUND

White blood cell count (WBC) as a measure of extramedullary leukemic cell survival is a well-known prognostic factor in acute lymphoblastic leukemia (ALL), but its biology, including impact of host genome variants, is poorly understood.

METHODS

We included patients treated with the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL-2008 protocol (N = 2347, 72% were genotyped by Illumina Omni2.5exome-8-Bead chip) aged 1-45 years, diagnosed with B-cell precursor (BCP-) or T-cell ALL (T-ALL) to investigate the variation in WBC. Spline functions of WBC were fitted correcting for association with age across ALL subgroups of immunophenotypes and karyotypes. The residuals between spline WBC and actual WBC were used to identify WBC-associated germline genetic variants in a genome-wide association study (GWAS) while adjusting for age and ALL subtype associations.

RESULTS

We observed an overall inverse correlation between age and WBC, which was stronger for the selected patient subgroups of immunophenotype and karyotypes (ρ_BCP-ALL  = -.17, ρ_T-ALL  = -.19; p < 3 × 10^-4 ). Spline functions fitted to age, immunophenotype, and karyotype explained WBC variation better than age alone (ρ = .43, p << 2 × 10^-6 ). However, when the spline-adjusted WBC residuals were used as phenotype, no GWAS significant associations were found. Based on available annotation, the top 50 genetic variants suggested effects on signal transduction, translation initiation, cell development, and proliferation.

CONCLUSION

These results indicate that host genome variants do not strongly influence WBC across ALL subsets, and future studies of why some patients are more prone to hyperleukocytosis should be performed within specific ALL subsets that apply more complex analyses to capture potential germline variant interactions and impact on WBC.

Design and Evaluation of TIM-3-CD28 Checkpoint Fusion Proteins to Improve Anti-CD19 CAR T-Cell Function

Therapeutic targeting of inhibitory checkpoint molecules in combination with chimeric antigen receptor (CAR) T cells is currently investigated in a variety of clinical studies for treatment of hematologic and solid malignancies. However, the impact of co-inhibitory axes and their therapeutic implication remains understudied for the majority of acute leukemias due to their low immunogenicity/mutational load. The inhibitory exhaustion molecule TIM-3 is an important marker for the interaction of T cells with leukemic cells. Moreover, inhibitory signals from malignant cells could be transformed into stimulatory signals by synthetic fusion molecules with extracellular inhibitory receptors fused to an intracellular stimulatory domain. Here, we designed a variety of different TIM-3-CD28 fusion proteins to turn inhibitory signals derived by TIM-3 engagement into T-cell activation through CD28. In the absence of anti-CD19 CAR, two TIM-3-CD28 fusion receptors with large parts of CD28 showed strongest responses in terms of cytokine secretion and proliferation upon stimulation with anti-CD3 antibodies compared to controls. We then combined these two novel TIM-3-CD28 fusion proteins with first- and second-generation anti-CD19 CAR T cells and found that the fusion receptor can increase proliferation, activation, and cytotoxic capacity of conventional anti-CD19 CAR T cells. These additionally armed CAR T cells showed excellent effector function. In terms of safety considerations, the fusion receptors showed exclusively increased cytokine release, when the CAR target CD19 was present. We conclude that combining checkpoint fusion proteins with anti-CD19 CARs has the potential to increase T-cell proliferation capacity with the intention to overcome inhibitory signals during the response against malignant cells.

Autophagy Regulates VDAC3 Ubiquitination by FBXW7 to Promote Erastin-Induced Ferroptosis in Acute Lymphoblastic Leukemia

Background: The discovery of ferroptosis is a major breakthrough in the development of cancer treatments. However, the mechanism by which ferroptosis contributes to acute lymphoblastic leukemia (ALL) is to be clarified. Here, we explored erastin-induced ferroptosis in ALL cells and the impact of autophagic activity on this process.

Materials and Methods: Cell viability was evaluated in various ALL cell lines following erastin treatment by the MTS assay, while cell death was evaluated via a trypan blue assay. Immunoblotting and quantitative real-time PCR were used to detect protein and mRNA expression, respectively. The UbiBrowser database was used to predict the E3 ligase of VDAC3, which was confirmed by immunoprecipitation. The role of FBXW7 in erastin-induced ferroptosis in vitro was evaluated via lentiviral-mediated silencing and overexpression. ALL xenograft mice were used to observe the impact of autophagy on erastin-induced ferroptosis.

Results: Resistance to erastin-induced ferroptosis was higher in Jurkat and CCRF-CEM cells than in Reh cells. The sensitivity could be modified by the autophagy activator rapamycin (Rapa) and the autophagy inhibitor chloroquine (CQ). Rapa sensitized ALL cells to erastin-induced ferroptosis. In ALL xenograft mice, the combination treatment of Rapa and erastin resulted in longer survival time than those observed with erastin or Rapa treatment alone. VDAC3 was regulated by autophagy post-transcriptionally, mainly via the ubiquitin-proteasome system (UPS). FBXW7 was verified as a specific E3 ligase of VDAC3. FBXW7 knockdown attenuated VDAC3 degradation by suppressing its ubiquitination, thereby increasing the sensitivity of ALL cells to erastin.

Conclusion: Autophagy regulated erastin-induced ferroptosis via the FBXW7-VDAC3 axis. Rapa sensitized ALL cells to erastin-induced ferroptosis both in vitro and in vivo. Our findings provide potential therapeutic targets for ALL.

Towards Raman-Based Screening of Acute Lymphoblastic Leukemia-Type B (B-ALL) Subtypes

Simple Summary

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy originating from abnormal lymphoid progenitor cells. Since ALL is genetically highly heterogenous, more sensitive and rapid methods for identifying the molecular subtype of ALL are still being searched, and Raman spectroscopy (RS) has a chance of becoming a valuable tool for this purpose. Herein, the RS was applied to analyze normal B cells and three subtypes of B-ALL, characterized by the presence of the product of gene fusion, i.e., BCR-ABL1, TEL-AML1, and TCF3-PBX1. The classification and discrimination of normal and neoplastic cells were carried out with the chemometric approach. Normal B cells were characterized mostly by bands assigned to nucleic acids and proteins, whereas three subtypes of ALL appeared to contain a higher lipid content. Spectral differences between particular ALL subtypes were modest. The results lead to the conclusion that RS has the potential as a diagnostic tool in clinical practice.

Abstract

Acute lymphoblastic leukemia (ALL) is the most common type of malignant neoplasms in the pediatric population. B-cell precursor ALLs (BCP-ALLs) are derived from the progenitors of B lymphocytes. Traditionally, risk factors stratifying therapy in ALL patients included age at diagnosis, initial leukocytosis, and the response to chemotherapy. Currently, treatment intensity is modified according to the presence of specific gene alterations in the leukemic genome. Raman imaging is a promising diagnostic tool, which enables the molecular characterization of cells and differentiation of subtypes of leukemia in clinical samples. This study aimed to characterize and distinguish cells isolated from the bone marrow of patients suffering from three subtypes of BCP-ALL, defined by gene rearrangements, i.e., BCR-ABL1 (Philadelphia-positive, t(9;22)), TEL-AML1 (t(12;21)) and TCF3-PBX1 (t(1;19)), using single-cell Raman imaging combined with multivariate statistical analysis. Spectra collected from clinical samples were compared with single-cell spectra of B-cells collected from healthy donors, constituting the control group. We demonstrated that Raman spectra of normal B cells strongly differ from spectra of their malignant counterparts, especially in the intensity of bands, which can be assigned to nucleic acids. We also showed that the identification of leukemia subtypes could be automated with the use of chemometric methods. Results prove the clinical suitability of Raman imaging for the identification of spectroscopic markers characterizing leukemia cells.

Extramedullary disease relapse and progression after blinatumomab therapy for treatment of acute lymphoblastic leukemia

BACKGROUND

Blinatumomab has demonstrated encouraging activity in relapsed/refractory (r/r) and minimal residual disease-positive (MRD+) acute lymphoblastic leukemia (ALL). Extramedullary disease (EMD) relapse or relapse with CD19- disease has been observed after blinatumomab therapy in patients with r/r or MRD+ ALL. However, the pathophysiology and risk factors of treatment failure are not fully understood.

METHODS

This study retrospectively reviewed the outcomes of adult patients with B-cell ALL treated with blinatumomab (n = 132) for either r/r (n = 103) or MRD+ disease (n = 29) at the authors' center (2013-2021) and analyzed factors associated with treatment response and EMD failure.

RESULTS

The overall response rate was 64%. A lower marrow blast burden before blinatumomab (P = .049) and no history of previous EMD (P = .019) were significantly associated with a higher response. Among the patients who responded to blinatumomab, 56% underwent consolidation with allogeneic transplantation. Blinatumomab failure was observed in 89 patients; 43% of these patients (n = 38) either progressed or relapsed at extramedullary sites. A history of extramedullary involvement (53% vs 24%; P = .005) and retention of CD19 expression at the time of relapse/progression (97% vs 74%; P = .012) were associated with a higher risk for extramedullary failure. Central nervous system (CNS) failure after blinatumomab was encountered in 39% of the patients with EMD.

CONCLUSIONS

A history of EMD predicted an inferior response to blinatumomab therapy with a higher risk for relapse/progression at extramedullary sites (particularly CNS). Consolidation with allogenic transplantation in patients who primarily responded to blinatumomab did not abrogate the risk of extramedullary relapse. The incorporation of extramedullary assessment and the intensification of CNS prophylaxis may help in addressing extramedullary failure.

LAY SUMMARY

Extramedullary failure is common during blinatumomab therapy for relapsed/refractory acute lymphoblastic leukemia. A history of extramedullary disease predicts an inferior response to blinatumomab therapy and a higher risk for relapse/progression at extramedullary sites. Most extramedullary failure cases retain CD19 expression.

MYBL2 Gene Polymorphism Is Associated With Acute Lymphoblastic Leukemia Susceptibility in Children

Purpose

Although MYBL2 had been validated to participate in multiple cancers including leukemia, the role of MYBL2 polymorphisms in acute lymphoblastic leukemia (ALL) was still not clear. In this study, we aimed to evaluate the association between MYBL2 single nucleotide polymorphisms (SNPs) and ALL risk in children.

Methods

A total of 687 pediatric ALL cases and 971 cancer-free controls from two hospitals in South China were recruited. A case-control study by genotyping three SNPs in the MYBL2 gene (rs285162 C>T, rs285207 A>C, and rs2070235 A>G) was conducted. The associations were assessed by odds ratios (ORs) with corresponding 95% confidence intervals (CIs). Subgroup and stratification analyses were conducted to explore the association of rs285207 with ALL risk in terms of age, sex, immunophenotype, risk level, and other clinical characteristics. The false-positive report probability (FPRP) analysis was performed to verify each significant finding. Functional analysis in silico was used to evaluate the probability that rs285207 might influence the regulation of MYBL2 .

Results

Our study demonstrated that rs285207 was related to a decreased ALL risk (adjusted OR = 0.78; 95% CI = 0.63-0.97, P = 0.022) in the dominant model. The associations of rs285207 with ALL risk appeared stronger in patients with pre B ALL (adjusted OR=0.56; 95% CI=0.38-0.84, P=0.004), with normal diploid (adjusted OR=0.73; 95% CI=0.57-0.95, P=0.017), with low risk (adjusted OR=0.68; 95% CI=0.49-0.94, P=0.021), with lower WBC (adjusted OR=0.62; 95% CI=0.43-0.87, P=0.007) or lower platelet level (adjusted OR=0.76; 95% CI=0.59-0.96, P=0.023). With FPRP analysis, the significant association between the rs285207 polymorphism and decreased ALL risk was still noteworthy (FPRP=0.128). Functional analysis showed that IKZF1 bound to DNA motif overlapping rs285207 and had a higher preference for the risk allele A. As for rs285162 C>T and rs2070235 A>G, no significant was found between them and ALL risk.

Conclusion

In this study, we revealed that rs285207 polymorphism decreased the ALL risk in children, and rs285207 might alter the binding to IKZF1, which indicated that the MYBL2 gene polymorphism might be a potential biomarker of childhood ALL.

Isolated CNS Relapse in Acute Lymphoblastic Leukemia (ALL): An Experience from a Tertiary Care Center

Aims and Objectives  In this study the various parameters of acute lymphoblastic leukemia (ALL), including the clinical features, peripheral blood and bone marrow (BM) findings, immunophenotypic and cytogenetic details in ALL cases who had isolated relapse involving the central nervous system (CNS), were studied.

Patients/Materials and Methods  Duration of the study is from 2015 to 2019 in which 5 ALL cases were presented to this tertiary care center. The presenting symptoms varied from headache, fever, and distension of abdomen. These cases were either on therapy or post completion of chemotherapy. The diagnosis of CNS relapse followed after the examination of cerebrospinal fluid (CSF). Patients also underwent BM examination to rule out systemic relapse.

Results  Age of patients ranged from 7 months to 42 years. There were three female patients. Two patients had isolated CNS relapse 3.5 years after completing therapy and succumbed to their illness. Two patients had t(9;22) while one patient had t(1;14) cytogenetic abnormality at diagnosis. One patient was diagnosed as T-ALL. Treatment offered was German Multicentre ALL protocol for induction along with 10 cycles of maintenance.

Conclusion  The most common hematolymphoid malignancy in children namely ALL accounts for 75% of childhood leukemias. Complete remission rates reach up to 70 to 80%. CNS involvement is known to occur in these cases. CNS relapse may occur alone or with systemic relapse. Advances in therapeutic protocols along with CNS prophylaxis have drastically brought down the rates of CNS relapse. It is essential to maintain a high degree of suspicion so that these cases of isolated CNS relapse can be identified at the earliest and definitive therapy can be offered.

Iron overload during the treatment of acute leukemia: pretransplant transfusion experience

BACKGROUND

Recent studies have shown the increased risk of mortality in cases with acute leukemia and iron overload. We aimed to determine the status of iron overload in patients with acute leukemia.

MATERIALS & METHODS

Patients diagnosed with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) between January 2015 and December 2019 were included in the study.

RESULTS

At 6 months, there were statistically more patients with serum ferritin >1000 in the AML group compared to the ALL group (p = 0,011).

CONCLUSION

Iron overload occurs earlier in patients with AML; the difference disappears after 6 months of treatment. It is the correct point to emphasize that iron overload is an important factor of pretransplant morbidity, especially in AML cases.

Leukemia With TCF3-ZNF384 Rearrangement as a Distinct Subtype of Disease With Distinct Treatments: Perspectives From A Case Report and Literature Review

Background

ZNF384 rearrangements are found in 5-10% of B-cell acute lymphoblastic leukemia (B-ALL) and 48% of B cell/myeloid mixed phenotype acute leukemia (B/M MPAL). ZNF384-rearranged B-ALL is prone to lineage conversion after chemotherapy. TCF3 is the second most common rearrangement partner of ZNF384 in B-ALL (27.5%) and the most common partner in B/M MPAL (53.3%). TCF3-ZNF384 fusion is related to a poor steroid response and a high frequency of relapse. It is mostly reported in children and adolescents but rarely seen in adults.

Patients and Methods

Here, we report a rare case of adult common B-ALL with TCF3-ZNF384 fusion in which the patient relapsed after one cycle of consolidation chemotherapy. Relapsed leukemia cells from the bone marrow were cultured for 72 hours ex vivo, and a panel of 156 kinds of cytotoxic drugs, targeted therapy drugs, combination chemotherapy drugs, etc., was used for sensitivity screening. The literature on TCF3-ZNF384 fusion was reviewed, and reported cases with TCF3-ZNF384 fusion were summarized. Clinical characteristics were compared between B-ALL and MPAL with TCF3-ZNF384 fusion.

Results

The relapsed lymphoblasts showed moderate sensitivity to both acute myelocytic leukemia (AML) - and acute lymphoblastic leukemia (ALL)-directed combination chemotherapy schemes, as well as to multiple targeted therapeutic drugs. The hyper-CVAD (B) scheme showed synergistic effects with multiple targeted compounds and had the highest sensitivity. The patient chose the hyper-CVAD (B) scheme combined with sorafenib and achieved complete remission (CR), then consolidated with myeloid-directed homoharringtonine+cytarabine+daunorubicin (HAD) scheme and gained molecular CR. By reviewing the literature, we found that both the genomic landscapes and gene expression profiles of ZNF384-rearranged B-ALL and MPAL are similar and that both diseases have lineage plasticity. The gene expression profile in TCF3-ZNF384-positive patients shows enrichment of hematopoietic stem cell features. No significant differences in clinical characteristics were found between TCF3-ZNF384-positive ALL and MPAL.

Conclusion

TCF3-ZNF384-positive leukemia may be a distinct subtype of leukemia regardless of immunophenotype. Considering the frequent lineage switches and sensitivity to both ALL- and AML-directed schemes, a uniform strategy directed at both lymphoid and myeloid lineages or at hematopoietic stem cells may be better for TCF3-ZNF384-positive leukemia. Small molecule targeted therapies may be promising treatment options and deserve further investigation.

Acute myeloid leukemia arising to genetic susceptibility genes related T cell acute lymphoblastic leukemia: case report

Fanconi anemia (FA) is the most common inherited bone marrow failure disorder, with a predisposition to neoplasia. While Myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) are the most common hematologic malignancies seen in patients with FA, cases of acute lymphoblastic leukemia (ALL) have also been described in the literature but it is uncommon. In our case report, a 12 years 5 months old boy, who was detected with heterozygote mutation of FANCC gene and nonsynonymous single nucleotide variability (SNV) mutation of AKAP9 gene, presented with precursor T cell ALL (T-ALL) at onset, myelodysplasia or myeloid biomarkers were not found at initial diagnosis. He received chemotherapy and achieved complete remission (CR) after a course of remission induction, but severe cytopenia was presented, sepsis and Invasive fungal infection also arose. With following-up and continue chemotherapy, secondary AML arose 17 months later, the patient died of sepsis related to chemotherapy at AML status. FA patients usually presented with homozygous or bilateral heterozygosity mutation in literature reports, whereas heterozygosity gene mutation of FANCC and AKAP9 has not reported yet. AKAP9 protein which was encoded by AKAP9 gene is widely distributed in many kinds of cells, thus ensuring the specificity and accuracy of signal transduction. We speculate that AKAP9 protein may interfere with the normal signal transduction of heterozygous mutation expression of FANCC gene and result in the inactivation of FANCC gene function. Unfortunately, the patient died of sepsis and we don't have enough blood samples to explore the role of AKAP9 gene mutation in patients with heterozygosity FANCC gene mutation.

Efficacy and safety of blinatumomab: Post hoc pooled analysis in Asian adults with relapsed/refractory B-cell precursor acute lymphoblastic leukemia

Background

Global studies have demonstrated the efficacy and safety of blinatumomab—a BiTE^® (bispecific T‐cell engager) targeted immuno‐oncology therapy that mediates the lysis of cells expressing CD19 in patients with relapsed/refractory acute lymphoblastic leukemia (R/R ALL). Because limited data are available in Asian patients, we conducted a post hoc pooled analysis in 45 Asian adult patients with R/R ALL—19 from the blinatumomab arm of TOWER (NCT02013167) and 26 from Study 265, a phase 1b/2 study in Japanese adults (NCT02412306).

Methods

Patients received a maximum of two cycles of induction blinatumomab for 4 weeks by continuous intravenous infusion (cycle 1/week 1: 9 μg/day; cycle 1/weeks 2–4: 28 μg/day) followed by 2 weeks of no blinatumomab (each 6‐week cycle); patients received 28 μg/day blinatumomab in subsequent cycles.

Results

Twenty of 45 patients enrolled (44%) achieved complete remission with full or partial hematologic recovery compared with 44% in TOWER and 80% and 38% in phase 1b and phase 2, respectively, of Study 265. The Kaplan–Meier (KM) median overall survival was 11.9 months (95% confidence interval [CI], 9.9–17.1) and the KM median duration of relapse‐free survival was 8.9 months (95% CI, 3.8–10.7). Ninety‐three percent of patients had grade ≥ 3 treatment‐emergent adverse events (AEs) compared with 87% in TOWER and 80% and 100% in phase 1b and phase 2, respectively, of Study 265. Five patients (11.4%) had fatal AEs.

Conclusions

The safety and efficacy of blinatumomab in Asian patients were comparable with those reported in previous global studies with no new safety signals.

Targeting Telomere Biology in Acute Lymphoblastic Leukemia

Increased cell proliferation is a hallmark of acute lymphoblastic leukemia (ALL), and genetic alterations driving clonal proliferation have been identified as prognostic factors. To evaluate replicative history and its potential prognostic value, we determined telomere length (TL) in lymphoblasts, B-, and T-lymphocytes, and measured telomerase activity (TA) in leukocytes of patients with ALL. In addition, we evaluated the potential to suppress the in vitro growth of B-ALL cells by the telomerase inhibitor imetelstat. We found a significantly lower TL in lymphoblasts (4.3 kb in pediatric and 2.3 kb in adult patients with ALL) compared to B- and T-lymphocytes (8.0 kb and 8.2 kb in pediatric, and 6.4 kb and 5.5 kb in adult patients with ALL). TA in leukocytes was 3.2 TA/C for pediatric and 0.7 TA/C for adult patients. Notably, patients with high-risk pediatric ALL had a significantly higher TA of 6.6 TA/C compared to non-high-risk patients with 2.2 TA/C. The inhibition of telomerase with imetelstat ex vivo led to significant dose-dependent apoptosis of B-ALL cells. These results suggest that TL reflects clonal expansion and indicate that elevated TA correlates with high-risk pediatric ALL. In addition, telomerase inhibition induces apoptosis of B-ALL cells cultured in vitro. TL and TA might complement established markers for the identification of patients with high-risk ALL. Moreover, TA seems to be an effective therapeutic target; hence, telomerase inhibitors, such as imetelstat, may augment standard ALL treatment.

Genetic Alterations and Therapeutic Targeting of Philadelphia-Like Acute Lymphoblastic Leukemia

Philadelphia-like (Ph-like) acute lymphoblastic leukemia (ALL) is a subgroup of B-cell precursor ALL which by gene expression analysis clusters with Philadelphia-positive ALL although lacking the pathognomonic BCR-ABL1 oncoprotein. Its prevalence increases with age and similar to BCR-ABL1-positive ALL, Ph-like ALL is characterized by IKZF1 or other B-lymphoid transcription factor gene deletions and by poor outcome to conventional therapeutic approaches. Genetic alterations are highly heterogenous across patients and include gene fusions, sequence mutations, DNA copy number changes and cryptic rearrangements. These lesions drive constitutively active cytokine receptor and kinase signaling pathways which deregulate ABL1 or JAK signaling and more rarely other kinase-driven pathways. The presence of activated kinase alterations and cytokine receptors has led to the incorporation of targeted therapy to the chemotherapy backbone which has improved treatment outcome for this high-risk subtype. More recently, retrospective studies have shown the efficacy of immunotherapies including both antibody drug-conjugates and chimeric antigen receptor T cell therapy and as they are not dependent on a specific genetic alteration, it is likely their use will increase in prospective clinical trials. This review summarizes the genomic landscape, clinical features, diagnostic assays, and novel therapeutic approaches for patients with Ph-like ALL.

Surgical treatment of recurrent acute lymphoblastic leukemia with humeral osteomyelitis as the first symptom: a case report and literature review

Osteomyelitis is a complication of acute lymphoblastic leukemia (ALL); however, its incidence rate is low. Recurrent ALL for which osteomyelitis is the first manifestation is rarer still. The repair and reconstruction of segmental bone defects caused by infection is a clinical problem. This article reports a rare case study of a 22-year-old male patient with recurrent ALL for which right humeral osteomyelitis was the first symptom including chills at first, recurrent fever and chills then, purulence from poster lateral right upper arm finally. Before treatment, the patient concealed his previous history of ALL. Debridement was performed, and the Masquelet technique and free fibula transplantation were used to reconstruct the humerus. ALL recurred with extensive bone invasion throughout the body 10 weeks after the humeral reconstruction. Despite the success of bone marrow transplantation, the patient died of complications. A limited follow-up period reveled that while leukemia extensively affected the bones of the patient's body, the reconstruction of the humerus was successful, and bone healing was good. This case study suggests that atypical or unexplained osteoarticular infection may be the precursor to some systemic diseases, and that Masquelet technology combined with free fibula transplantation is one of the best choices to treat segmental bone defects.

LncRNA VPS9D1-AS1 promotes cell proliferation in acute lymphoblastic leukemia through modulating GPX1 expression by miR-491-5p and miR-214-3p evasion

Alterations in messenger RNAs (mRNAs) of protein-coding genes can influence the malignant behaviors of acute lymphoblastic leukemia (ALL) cells. According to the prediction from The Cancer Genome Atlas (TCGA) database, we discovered that glutathione peroxidase 1 (GPX1) was up-regulated in acute myeloid leukemia (LAML) tissues, which pushed us to explore the feasible role and its related modulatory mechanism of GPX1 in ALL. In this research, we first proved the high expression of GPX1 in ALL cells compared with normal cells. Functional assays further revealed that the proliferation was obstructed and the apoptosis was facilitated in ALL cells with silenced GPX1. Then, both miR-491-5p and miR-214-3p that were down-regulated in ALL cells were affirmed to target GPX1. Subsequently, VPS9D1 antisense RNA 1 (VPS9D1-AS1) was recognized as the upstream regulator of miR-491-5p-miR-214-3p/GPX1 axis in a competing endogenous RNA (ceRNA) model. Importantly, we proved that VPS9D1-AS1 served as a tumor promoter in ALL through elevating GPX1. In conclusion, VPS9D1-AS1 contributed to ALL cell proliferation through miR-491-5p-miR-214-3p/GPX1 axis, hinting an optional choice for the treatment of ALL.

The advantage of chimeric antigen receptor T cell therapy in pediatric acute lymphoblastic leukemia with E2A-HLF fusion gene positivity: a case series

The E2A-HLF fusion gene is a very poor biomarker in acute lymphoblastic leukemia (ALL) because of its high relapse risk, even with the most intensive chemotherapy and hematopoietic stem cell transplantation (HSCT). Here, we analyzed four cases diagnosed with E2A-HLF fusion gene-positive B-ALL and treated with the CCCG-ALL-2015 protocol based on high-risk stratification from Jun 2017 to May 2020 retrospectively. Three cases (Case 1, 2, 3) were insensitive to conventional therapy and inhibitors with high-level MRD on days 19 and 46, but they all achieved complete remission at the molecular level with Chimeric Antigen Receptor (CAR) T cell therapy regardless of primary resistance or recurrence. Although remission was initially achieved for Case 4, chemotherapeutics was not sensitive after recurrence. However, CAR-T cell therapy gave him the chance to obtain complement remission again. Cytokine release syndrome (CRS) with fever, chills, acute kidney injury, hypotension and capillary leak syndrome and CAR-T related encephalopathy syndrome (CRE) with seizures and encephaledema occurred after CAR-T cell therapy, but symptoms disappeared with effective intensive care. Overall, CAR-T cell therapy enabled the patients to achieve complement remission with controllable adverse events. Our results indicated that CAR-T cell therapy is a feasible and effective therapy for patients with E2A-HLF-positive B-ALL and prompted the authors to report these cases.

Expenditures among young adults with acute lymphoblastic leukemia by site of care

BACKGROUND

Individuals diagnosed with acute lymphoblastic leukemia (ALL) between the ages of 22 and 39 years experience worse outcomes than those diagnosed when they are 21 years old or younger. Treatment at National Cancer Institute-designated Comprehensive Cancer Centers (CCC) mitigates these disparities but may be associated with higher expenditures.

METHODS

Using deidentified administrative claims data (OptumLabs Data Warehouse), the cancer-related expenditures were examined among patients with ALL diagnosed between 2001 and 2014. Multivariable generalized linear model with log-link modeled average monthly health-plan-paid (HPP) expenditures and amount owed by the patient (out-of-pocket [OOP]). Cost ratios were used to calculate excess expenditures (CCC vs non-CCC). Incidence rate ratios (IRRs) compared CCC and non-CCC monthly visit rates. Models adjusted for sociodemographics, comorbidities, adverse events, and months enrolled.

RESULTS

Clinical and sociodemographic characteristics were comparable between CCC (n = 160) and non-CCC (n = 139) patients. Higher monthly outpatient expenditures in CCC patients ($15,792 vs $6404; P < .001) were driven by outpatient hospital HPP expenditures. Monthly visit rates and per visit expenditures for nonchemotherapy visits (IRR = 1.6; P = .001; CCC = $8247, non-CCC = $1191) drove higher outpatient hospital expenditures among CCCs. Monthly OOP expenditures were higher at CCCs for outpatient care (P = .02). Inpatient HPP expenditures were significantly higher at CCCs ($25,918 vs $13,881; ꞵ = 0.9; P < .001) before accounting for adverse events but were no longer significant after adjusting for adverse events (ꞵ = 0.4; P = .1). Hospitalizations and length of stay were comparable.

CONCLUSIONS

Young adults with ALL at CCCs have higher expenditures, likely reflecting differences in facility structure, billing practices, and comprehensive patient care. It would be reasonable to consider CCCs comparable to the oncology care model and incentivize the framework to achieve superior outcomes and long-term cost savings.

LAY SUMMARY

Health care expenditures in young adults (aged 22-39 years) with acute lymphoblastic leukemia (ALL) are higher among patients at National Cancer Institute-designated Comprehensive Cancer Centers (CCC) than those at non-CCCs. The CCC/non-CCC differences are significant among outpatient expenditures, which are driven by higher rates of outpatient hospital visits and outpatient hospital expenditures per visit at CCCs. Higher expenditures and visit rates of outpatient hospital visits among CCCs may also reflect how facility structure and billing patterns influence spending or comprehensive care. Young adults at CCCs face higher inpatient HPP expenditures; these are driven by serious adverse events.

Hypodiploid B-Lymphoblastic Leukemia Presenting as an Isolated Orbital Mass Prior to Systemic Involvement: A Case Report and Review of the Literature

We describe a 4-year-old boy who presented with progressive right periorbital edema and proptosis, with no systemic symptoms, who was found to have B-lymphoblastic leukemia (B-ALL). Magnetic resonance imaging (MRI) showed an enhancing mass centered in the right superolateral extraconal orbit. Orbital biopsy was consistent with B-ALL (CD99, TdT, LCA cocktail, CD34, CD79, CD10, PAX5, MIB1 positive; CD3, CD20 negative). A subsequent bone marrow aspirate confirmed a diagnosis of B-ALL with 80% blasts by flow cytometry and haploid cytogenetic findings. The patient improved clinically after chemotherapy. There are seven cases previously reported in the literature with hematogenous orbital masses at initial presentation of childhood ALL, but all with systemic symptoms or an abnormal complete blood count (CBC) at presentation. Our case is the first report in which an orbital mass preceded detectable systemic or laboratory evidence of ALL. This patient highlights the importance of differentiating benign causes of eyelid swelling from malignant ones.

Detection of New Translocation in Infant Twins with Concordant ALL and Discordant Outcome

About 2-5% of acute lymphoblastic leukemia (ALL) cases in pediatric patients are infants with an unfavorable prognosis because of high relapse probability. Early detection of the disease is, therefore, very important. Despite the fact that leukemia in twins occurs rarely, more attention has been paid to it in genetic studies. In the present study, through cytogenetic testing, a special case of concordant ALL in monozygotic twins was presented with different outcomes. In spite of an acceptable initial consequence to medical treatment in twins, in another brother (Twin B), early relapse was observed. In the cytogenetic study, both twins expressed t (4; 11) (q21; q23) while twin A expressed t (2; 7) (p10; q10). No cases have previously reported this mutation. Whether this translocation has a protective role for leukemia with mixed-lineage leukemia (MLL) gene rearrangement is still unclear. The difference in the translocation identified in the identical twins is also subject to further investigations.

Gene Modified CAR-T Cellular Therapy for Hematologic Malignancies

With advances in the understanding of characteristics of molecules, specific antigens on the surface of hematological malignant cells were identified and multiple therapies targeting these antigens as neoplasm treatments were developed. Among them, chimeric antigen receptor (CAR) T-cell therapy, which got United States Food and Drug Administration (FDA) approval for relapsed/refractory (r/r) diffuse large B-cell lymphoma (DLBCL) as well as for recurrent acute lymphoblastic leukemia (ALL) within the past five years, and for r/r mantle cell lymphoma (MCL) this year, represents one of the most rapidly evolving immunotherapies. Nevertheless, its applicability to other hematological malignancies, as well as its efficacy and persistence are fraught with clinical challenges. Currently, more than one thousand clinical trials in CAR T-cell therapy are ongoing and its development is changing rapidly. This review introduces the current status of CAR T-cell therapy in terms of the basic molecular aspects of CAR T-cell therapy, its application in hematological malignancies, adverse reactions during clinical use, remaining challenges, and future utilization.

Long-term survival of patients with relapsed/refractory acute lymphoblastic leukemia treated with blinatumomab

Background

Blinatumomab is a CD19 BiTE (bispecific T‐cell engager) immuno‐oncology therapy that mediates the lysis of cells expressing CD19.

Methods

A pooled analysis of long‐term follow‐up data from 2 phase 2 studies that evaluated blinatumomab in heavily pretreated adults with Philadelphia chromosome–negative, relapsed/refractory B‐cell precursor acute lymphoblastic leukemia was conducted.

Results

A total of 259 patients were included in the analysis. The median overall survival (OS) among all patients, regardless of response, was 7.5 months (95% confidence interval [CI], 5.5‐8.5 months); the median follow‐up time for OS was 36.0 months (range, 0.3‐60.8 months). The median relapse‐free survival (RFS) among patients who achieved a complete remission (CR) or complete remission with partial hematologic recovery (CRh) in the first 2 cycles (n = 123) was 7.7 months (95% CI, 6.2‐10.0 months); the median follow‐up time for RFS was 35.0 months (range, 9.5‐59.5 months). OS and RFS plateaued with 3‐year rates of 17.7% and 23.4%, respectively. The cumulative incidence function of the time to relapse, with death not due to relapse considered a competing risk, for patients who achieved a CR/CRh within 2 cycles of treatment also plateaued with a 3‐year relapse rate of 59.3%. For patients who achieved a CR/CRh with blinatumomab followed by allogeneic hematopoietic stem cell transplantation while in continuous CR, the median OS was 18.1 months (95% CI, 10.3‐30.0 months) with a 3‐year survival rate of 37.2%.

Conclusions

These data suggest that long‐term survival is possible after blinatumomab therapy.

Lay Summary

Immuno‐oncology therapies such as blinatumomab activate the patient's own immune system to kill cancer cells.

This study combined follow‐up data from 2 blinatumomab‐related clinical trials to evaluate long‐term survival in patients with relapsed and/or refractory B‐cell precursor acute lymphoblastic leukemia at high risk for unfavorable outcomes.

Among patients who achieved a deep response with blinatumomab, one‐third lived 3 years or longer. These findings suggest that long‐term survival is possible after treatment with blinatumomab.

Patients achieving remission after blinatumomab can have a durable response. The survival plateau indicates a high probability of a cure in those patients responding to blinatumomab and alive after 3 years.

Pediatric Acute Lymphoblastic Leukemia Patients Exhibit Distinctive Alterations in the Gut Microbiota

Previous studies have shown that gut microbiota can affect human immune system in many ways. Our aim was to investigate quantitative differences in fecal bacterial compositions of childhood acute lymphoblastic leukemia (ALL) patients compared to those of healthy children, so as to identify individual bacterial species that are related to the etiology of ALL. We recruited 81 subjects, including 58 patients with ALL and 23 healthy controls. Fecal samples were collected and examined by 16S rRNA quantitative arrays and bioinformatics analysis. Both Principal Coordinates Analysis (PCoA) and Non-metric Multidimensional scaling (NMDS) demonstrated that the microbial composition of ALL patients deviated from the tight cluster of healthy controls. Multiple bacterial species exhibited significant changes (e.g., Roseburia faecis, Edwardsiella tarda, and Fusobacterium naviforme) in the ALL samples. Some of the differentially abundant taxa were correlated with the level of interleukin-10. The ALL cases could be efficiently distinguished from healthy controls by the random forest model based on differential species (area under ROC curve = 0.843). Taken together, the composition of gut microbiota differed from healthy controls to pediatric ALL patients. Our study identified a series of ALL-related species in the gut microbiota, providing a new direction for future studies aiming to understand the host-gut microbiota interplay in ALL pathogenesis.

Production and characterization of haploidentical CD19 CAR T cells: Validated to induce a continuous complete remission in a patient with relapsed refractory B-cell ALL

AIMS

The purpose of this study was to design and manufacture CD19 chimeric antigen receptor (CAR)-modified T cells for clinical use in Thailand, as a model for how this technology can be directly applied at individual institutions treating high-risk leukemia patients.

METHODS

We constructed second-generation CAR T cells expressing CD19 scFV-CD28-CD3ζ with different lengths of the spacer region: full, intermediate, and short length, by using a lentiviral vector. We wanted to determine whether the difference in length of the spacer would affect the cytotoxic potential of the CD19 CAR T cells against the leukemic cells.

RESULTS

We found that all constructs of CD19 CAR T cells exhibited a similar level of cytotoxicity against several human lymphoma and leukemia cell lines. For the clinical application, we chose the intermediate length spacer construct CD19 CAR T cells, hypothesizing that the highest transduction efficiency coupled with a slower initial proliferation in vitro might lead to effective leukemic cell kill, yet a lower probability for serious clinical side effects. We then tested the clinical efficacy of our CD19 CAR T cells in one patient with refractory/relapsed acute B-cell lymphoblastic leukemia. This patient indeed had minimal clinical side effects after the CAR T-cell infusion, and he remains in an unmaintained, ongoing complete remission 10+ months after his T-cell treatment.

CONCLUSION

Our CD19 CAR T cells demonstrated efficacies in acute lymphoblastic B-cell leukemia, and will be used to establish an immunotherapeutic program for high-risk B-cell acute lymphoblastic leukemia in Thailand. We propose that this approach can be used as a model for how this new exciting technology can be applied directly at individual institutions that treat (a large number of) patients with high-risk leukemia.

Philadelphia chromosome-positive acute lymphoblastic leukemia: a case report

Prognosis of patients with Philadelphia-positive acute lymphoblastic leukemia (Ph-ALL) relapsing after allogeneic hematopoietic stem cell transplantation (HSCT) is extremely poor. Therefore, effective alternative therapeutic measures are urgently needed. Recently, the use of antigen receptor-modified T cells holds great promise for relapsed and refractory ALL treatment. Prior to chimeric antigen receptor T-cell (CAR-T) infusion conditioning chemotherapy is used routinely to establish a favorable in vivo environment for CAR-T expansion, which has mostly involved fludarabine and cyclophosphamide. We report on a patient presented with extreme fatigue and anemia and was diagnosed with relapsed and refractory acute lymphoblastic leukemia (ALL) harbored T315I-BCR-ABL mutation, who had undergone allogeneic HSCT and multiple reinducing chemotherapy, but achieved complete hematologic remission (CHR) with CAR -T infusion as a later salvage treatment. Prior to CAR-T infusion there was no conditioning chemotherapy, but a bone marrow suppression period induced by ponatinib. CAR-T cell infusion was well tolerated and the patient achieved a CHR and maintained it for three months. At present, there is no relevant report on the use of tyrosine kinase inhibitors (TKI) as preconditioning protocols before CAR-T cells infusion. Our case indicated ponatinib not only reduces tumor burden but may also serve as a conditioning regimen for CAR-T therapy in the treatment of relapsed and refractory Ph-ALL.

Distance to treatment center is associated with survival in children and young adults with acute lymphoblastic leukemia

BACKGROUND

Socioeconomic and demographic categories such as income, race, insurance status, and treatment center type are associated with outcomes in acute leukemia. This study was aimed at determining whether the distance to treatment center affects overall survival for children and young adults with acute leukemia.

METHODS

The National Cancer Database was queried for patients 39 years old or younger who were diagnosed with acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL). A backward elimination procedure was used to select final multivariate Cox models.

RESULTS

In total, 12,301 patients with AML and 22,683 patients with ALL were analyzed. The ALL model included distance to treatment center, Charlson-Deyo score, age, race, insurance status, and community income level. US census definitions of urban and rural were not statistically significant, and no interaction was significant for included variables. Compared with distances > 50 miles, all other distances were associated with improved survival (hazard ratio [HR] for ≤10 miles, 0.91; P = .04; HR for >10 to ≤20 miles, 0.86; P = .004; HR for >20 to ≤50 miles, 0.87; P = .005). The final model for AML included the same variables as the ALL model except for distance to treatment center, which was not statistically significant.

CONCLUSIONS

For children and young adults with ALL, distances > 50 miles are associated with inferior overall survival; however, no difference is seen for AML. Although it is unknown whether differences in survival for patients with ALL based on distance are driven by relapse or treatment-related mortality, increased attention to adherence, supportive care, and logistics for patients traveling long distances is warranted.

LAY SUMMARY

For children and young adults with acute lymphoblastic leukemia, living more than 50 miles from the treatment center is associated with worse outcomes.

Use of Allopurinol to Mitigate 6-Mercaptopurine Associated Gastrointestinal Toxicity in Acute Lymphoblastic Leukemia

An essential component of acute lymphoblastic leukemia (ALL) therapy is the prolonged maintenance phase with daily 6-mercaptopurine (6-MP) as the cornerstone. While 6-MP is generally well-tolerated, some patients suffer from significant side effects such as gastrointestinal (GI) toxicity, including hepatitis, hypoglycemia, nausea, and pancreatitis, which can substantially limit the tolerated dose of 6-MP. These toxicities are thought to result from skewed metabolism of 6-MP leading to an accumulation of the 6-methylmercaptopurine (6-MMP) metabolite. Here, we describe current knowledge behind the use of allopurinol to modify 6-MP metabolism and improve tolerance to therapy. This method has been successfully used in adults with inflammatory bowel disease refractory to purine therapy and has been modified for use in children with GI toxicities related to 6-MP in maintenance therapy for ALL. Use of allopurinol for 6-MP related toxicities should be reserved for patients in which an alternative cause of signs or symptoms has been excluded and for whom non-pharmacologic measures have failed. When allopurinol is used, simultaneous dose reduction of 6-MP is required to avoid severe myelosuppression and related side effects, though overall combination therapy appears to be well-tolerated and effective when instituted appropriately.

Integrated Genomic Analysis of Chromosomal Alterations and Mutations in B-Cell Acute Lymphoblastic Leukemia Reveals Distinct Genetic Profiles at Relapse

The clonal basis of relapse in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is complex and not fully understood. Next-generation sequencing (NGS), array comparative genomic hybridization (aCGH), and multiplex ligation-dependent probe amplification (MLPA) were carried out in matched diagnosis–relapse samples from 13 BCP-ALL patients to identify patterns of genetic evolution that could account for the phenotypic changes associated with disease relapse. The integrative genomic analysis of aCGH, MLPA and NGS revealed that 100% of the BCP-ALL patients showed at least one genetic alteration at diagnosis and relapse. In addition, there was a significant increase in the frequency of chromosomal lesions at the time of relapse (p = 0.019). MLPA and aCGH techniques showed that IKZF1 was the most frequently deleted gene. TP53 was the most frequently mutated gene at relapse. Two TP53 mutations were detected only at relapse, whereas the three others showed an increase in their mutational burden at relapse. Clonal evolution patterns were heterogeneous, involving the acquisition, loss and maintenance of lesions at relapse. Therefore, this study provides additional evidence that BCP-ALL is a genetically dynamic disease with distinct genetic profiles at diagnosis and relapse. Integrative NGS, aCGH and MLPA analysis enables better molecular characterization of the genetic profile in BCP-ALL patients during the evolution from diagnosis to relapse.

Frontline Blinatumomab in Older Adults with Philadelphia Chromosome-Negative B-Cell Acute Lymphoblastic Leukemia

Outcomes of acute lymphoblastic leukemia (ALL) in older adults treated with chemotherapy are poor. The CD19/CD3 bispecific T-cell engager (BiTE) antibody blinatumomab is approved for refractory, relapsed or minimal/measurable residual disease (MRD)-positive B-cell ALL, but there is little experience in the upfront setting, including in older patients. We retrospectively analyzed outcomes of blinatumomab monotherapy in five newly diagnosed Philadelphia chromosome-negative B-cell ALL patients over 70 years. Three had cytokine release syndrome, treated with dexamethasone and/or tocilizumab, and four patients had neurotoxicity, treated with dexamethasone, without blinatumomab interruption. All five achieved complete remission (CR) after cycle one, three with undetectable MRD. All five were alive at 8 to 15 months. Three remained in MRD-negative CR. Two relapsed after cycle 3, one with extramedullary disease. In our small cohort of patients over 70 years, blinatumomab was safe initial therapy and produced a high response rate.

Expression of the nucleoside transporters hENT1 (SLC29) and hCNT1 (SLC28) in pediatric acute myeloid leukemia

Cellular uptake of clinically important deoxynucleoside analogs is mediated by nucleoside transporters including the human equilibrative nucleoside transporter 1 (hENT1) and the concentrative nucleoside transporter-1 (hCNT1). These transporters are responsible for influx of cytarabine and reduced hENT1 expression is a major resistance mechanism in acute myeloid leukemia. We determined hENT1 and hCNT1 protein expression by immunocytochemistry in 50 diagnostic pediatric acute myeloid leukemia patient samples. All samples expressed hENT1 [9/43 (21%) low; 26/43 (60%) medium and 8/43 (19%) high] and hCNT1 [2/42 (5%) low; 35/42 (83%) medium and 5/42 (12%) high] at the cell membrane and cytoplasm. Statistical analysis showed a non-significant relationship between survival and transporter expression and in vitro drug sensitivity. In conclusion, the nucleoside transporters hENT1 and hCNT1 are broadly expressed in pediatric acute myeloid leukemia at diagnosis.

Campylobacter jejuni bacteremia in Italian pediatric patients with acute lymphoblastic leukemia: Report of two cases

Infections caused by Campylobacter jejuni are rarely associated with extraintestinal complications. C. jejuni bacteremia is difficult to detect in patients with hematological malignancies undergoing chemotherapy where the choice of appropriate antibiotic treatment is extremely important. We report two cases of C. jejuni bacteremia in Italian pediatric patients affected by acute lymphoblastic leukemia (ALL). Agreeing with the most recent epidemiological data, both clinical isolates showed a typical phenotypic antimicrobial resistance patterns with combined resistance to ciprofloxacin and tetracycline. To our knowledge, this is the first report of C. jejuni isolation from the blood of ALL pediatric patients in Italy, and it provides important epidemiological information on this rare infection.

Analysis of the rRNA methylation complex components in pediatric B-cell precursor acute lymphoblastic leukemia: A pilot study

BACKGROUND

Dysregulation of ribosome biogenesis and alteration of ribosome composition, including alteration in ribosomal RNA (rRNA) 2'-O-ribose methylation, can play a role in malignant transformation and cancer progression. Several studies recently reported that components of the rRNA methylation complex are associated with leukemogenesis. However, no study ever investigated the alteration of ribosome biogenesis factors in the most common pediatric malignancy - B-cell precursor acute lymphoblastic leukemia (BCP-ALL).

OBJECTIVES

The objective of this study was to examine the expression of factors building the rRNA methylation complex, either the protein components (1 methyl-transferase (FBL), NOP56, NOP58, NHP2L1) or some RNA components (box C/D snoRNAs: SNORD35B, SNORD65, SNORD46, SNORD50A, SNORD38B), as well as CMYC, and nucleolin (NCL) - a protein involved in rRNA synthesis. Clinical effects in children with BCP-ALL were also investigated.

MATERIAL AND METHODS

The factors involved in ribosome biogenesis were studied in 28 children with BCP-ALL with the use of real-time polymerase chain reaction (RT-PCR) using the BioMark HD System (Fluidigm, San Francisco, USA) in cDNA prepared from the bone marrow samples collected at diagnosis.

RESULTS

Strong correlations were observed between NOP56, NOP58 and NCL, and multiple weaker correlations were observed in the box C/D snoRNA category, and between box C/D snoRNA and transcripts coding proteins of the rRNA methylation complex. The expression of analyzed transcripts did not correlate with the initial white blood cells count (WBC) or with bone marrow blast percentage. Ribosome biogenesis upregulation with overexpression of FBL and NOP56, and CMYC was found in patients who subsequently relapsed and the upregulation signature was not associated with known risk predictors.

CONCLUSIONS

This is the first report on the clinical aspect of ribosome biogenesis in pediatric BCP-ALL, and it shows that overexpression of CMYC and C/D box nucleoproteins FBL and NOP56 is an antecedent event in patients who subsequently relapse. The dysregulation pattern is different from the previous reports in acute myeloid leukemia (AML), suggesting that dysregulation of ribosome biogenesis is specific for BCP-ALL.

Clinical Relevance of Immunobiology in Umbilical Cord Blood Transplantation

Umbilical cord blood transplantation (UCBT) has been an important donor source for allogeneic hematopoietic stem cell transplantation, especially for patients who lack suitable matched donors. UCBT provides unique practical advantages, such as lower risks of graft-versus-host-disease (GVHD), permissive HLA mismatch, and ease of procurement. However, there are clinical challenges in UCBT, including high infection rates and treatment-related mortality in selected patient groups. These clinical advantages and challenges are tightly linked with cell-type specific immune reconstitution (IR). Here, we will review IR, focusing on T and NK cells, and the impact of IR on clinical outcomes. Better understanding of the immune biology in UCBT will allow us to further advance this field with improved clinical practice.

Diabetes mellitus among adult survivors of childhood acute lymphoblastic leukemia: A report from the St. Jude Lifetime Cohort Study

BACKGROUND

Greater than one-half of children who are treated for acute lymphoblastic leukemia (ALL) develop ≥1 treatment-related medical conditions in their lifetime, many of which are known risk factors for diabetes mellitus. In the current study, the authors evaluated the prevalence and risk factors of diabetes mellitus among clinically assessed adult survivors of childhood ALL METHODS: The authors performed a retrospective evaluation of data from survivors of ALL and community controls who were enrolled in the St. Jude Lifetime Cohort Study between October 1, 2007, and June 30, 2016. Participants were adults with ≥10 years of survival of childhood ALL and community controls who completed clinical and laboratory evaluations. Data for the current analysis were abstracted from medical records. Exposures evaluated herein included chemotherapy and radiation exposures and medical history, including drug-induced diabetes mellitus.

RESULTS

Of 1360 eligible adults who were ≥10-year survivors of childhood ALL, a total of 1044 completed the evaluations; these individuals had a mean age of 33.97±9.14 years and 50.86% were male. The 368 controls, 45.65% of whom were male, had a mean age of 35.33±10.21 years. Type 2 diabetes mellitus (T2DM) was found in approximately 7.47% of survivors and 3.80% of controls (odds ratio [OR], 2.07; 95% CI, 1.11-3.87). In adjusted models, among survivors, older age (OR, 1.05 for each additional year; 95% CI, 1.02-1.08), body mass index ≥30 kg/m² (OR, 7.40; 95% CI, 2.61-20.97), and drug-induced diabetes mellitus occurring during ALL therapy (OR, 4.67; 95% CI, 2.53-8.61) were found to be associated with T2DM.

CONCLUSIONS

Adult survivors of childhood ALL are at an increased risk of T2DM. Adult survivors of childhood ALL who are of older age, with an overweight or obese body mass index, and/or who developed drug-induced diabetes mellitus during treatment should be closely monitored for T2DM during long-term follow-up.

FOXO3 gene polymorphisms influence the risk of acute lymphoblastic leukemia in Chinese children

Acute lymphoblastic leukemia (ALL) is the most frequently diagnosed cancer in children and single-nucleotide polymorphisms (SNPs) in certain genes influence risk of ALL. Although FOXO3 had been demonstrated to be involved leukemia, the role of FOXO3 polymorphisms was still not clear. In the present study, we explored the association of FOXO3 SNPs with ALL risk in Chinese children. We genotyped four polymorphisms (rs17069665 A>G, rs4945816 T>C, rs4946936 C>T, and rs9400241 A>C) of FOXO3 in 425 ALL cases and 1339 health controls. The associations were estimated by odds ratios (ORs) with their 95% confidence intervals (CIs). Further analyses were performed to explore associations of rs17069665 and rs9400241 with ALL susceptibility in terms of age, gender, immunophenotype, minimal residual disease (MRD), and other clinical characteristics. We found rs17069665 related to the increased ALL risk (OR = 1.76; 95% CI = 1.02-3.04), rs9400241 related to decreased ALL risk (OR = 0.80; 95% CI = 0.64-0.99). The effects of rs17069665 on ALL risk were more predominant in males and children < 10 years, and patients with lower rates of platelet or neutrophil. As for rs9400241, the effects were more predominant in children < 10 years, and in patients with pre B ALL, positive MRD, anemia, or hepatomegaly. In conclusion, FOXO3 gene polymorphisms influence the risk of ALL in children and might be a potential biomarker for ALL susceptibility.

Minimal Residual Disease in Acute Lymphoblastic Leukemia: Technical and Clinical Advances

Introduction: Acute lymphoblastic leukemia (ALL) is the first neoplasm where the assessment of early response to therapy by minimal residual disease (MRD) monitoring has proven to be a fundamental tool to guide therapeutic choices. The most standardized methods to study MRD in ALL are multi-parametric flow cytometry (MFC) and polymerase chain reaction (PCR) amplification-based methods. Emerging technologies hold the promise to improve MRD detection in ALL patients. Moreover, novel therapies, such as monoclonal antibodies, bispecific T-cell engagers, and chimeric antigen receptor T cells (CART) represent exciting advancements in the management of B-cell precursor (BCP)-ALL.

Aims: Through a review of the literature and in house data, we analyze the current status of MRD assessment in ALL to better understand how some of its limitations could be overcome by emerging molecular technologies. Furthermore, we highlight the future role of MRD monitoring in the context of personalized protocols, taking into account the genetic complexity in ALL.

Results and Conclusions: Molecular rearrangements (gene fusions and immunoglobulin and T-cell receptor-IG/TR gene rearrangements) are widely used as targets to detect residual leukemic cells in ALL patients. The advent of novel techniques, namely next generation flow cytometry (NGF), digital-droplet-PCR (ddPCR), and next generation sequencing (NGS) appear important tools to evaluate MRD in ALL, since they have the potential to overcome the limitations of standard approaches. It is likely that in the forthcoming future these techniques will be incorporated in clinical trials, at least at decisional time points. Finally, the advent of new powerful compounds is further increasing MRD negativity rates, with benefits in long-term survival and a potential reduction of therapy-related toxicities. However, the prognostic relevance in the setting of novel immunotherapies still needs to be evaluated.

Targeting PI3K Signaling in Acute Lymphoblastic Leukemia

Adhesion of acute lymphoblastic leukemia (ALL) cells to bone marrow stroma cells triggers intracellular signals regulating cell-adhesion-mediated drug resistance (CAM-DR). Stromal cell protection of ALL cells has been shown to require active AKT. In chronic lymphocytic leukemia (CLL), adhesion-mediated activation of the PI3K/AKT pathway is reported. A novel FDA-approved PI3Kδ inhibitor, CAL-101/idelalisib, leads to downregulation of p-AKT and increased apoptosis of CLL cells. Recently, two additional PI3K inhibitors have received FDA approval. As the PI3K/AKT pathway is also implicated in adhesion-mediated survival of ALL cells, PI3K inhibitors have been evaluated preclinically in ALL. However, PI3K inhibition has yet to be approved for clinical use in ALL. Here, we review the role of PI3K in normal hematopoietic cells, and in ALL. We focus on summarizing targeting strategies of PI3K in ALL.