Types Of Leukemia Research Articles

Abstract 6564: SOS1 inhibitor treatment improves response to Venetoclax in acute myeloid leukemia

Abstract Acute myeloid leukemia (AML) is the most common type of acute leukemia in adults. First-line treatment of AML patients consists primarily of chemotherapy, sometimes combined with a targeted therapy. However, elderly patients unfit for chemotherapy receive venetoclax, a BCL2 inhibitor, combined with azacitadine or decitabine. While responses in these patients are high (50-70%, with median OS of 10-17 months), around 30-50% of them do not respond and most relapse within 1-10 years. Increased MAPK pathway activity or low frequency RAS pathway mutations have been identified as key mediators of resistance to standard-of-care targeted therapies for AML, including venetoclax. Here, we found that in DepMap whole-genome CRISPR screens, leukemia cell lines, including AML, show a particular dependency on SOS1. A subsequent PRISM screen with a selective inhibitor of SOS1 confirmed these results. To validate these results in vitro, we treated 7 AML cell lines showing strongest dependency on SOS1 based on DepMap and PRISM screens, with SOS1i or a SHP2 inhibitor. We found that in 4 of 7 cell lines treatment with SOS1i or SHP2i strongly impaired proliferation. In 3 of 4 responding cell lines, the anti-proliferative effect with either SOS1i or SHP2i was stronger than azacytidine single agent treatment. We next treated 29 primary ex vivo cultures of AML with SOS1i and found that the treatment induced strong or intermediate anti-proliferative effect in 21 of 29 models (72%). In two AML PDX models, treatment with SOS1i as a single agent resulted in approximately 25% reduction of human CD45+ AML blast cells in both models. Venetoclax treatment led to approximately 75% decrease in AML blasts, while the combined venetoclax and SOS1i treatment resulted in near complete eradication of the disease. Annexin V staining of AML monoblasts demonstrated that this decrease was due to an increase in apoptosis in the combination groups. In summary, we demonstrate that SOS1 inhibitor treatment may be used to improve responses to venetoclax in AML patients. Citation Format: Kaja Kostyrko, Melanie Hinkel, Matthew G. Rees, Melissa M. Ronan, Jennifer A. Roth, Daniel Gerlach, Irene Waizenegger. SOS1 inhibitor treatment improves response to Venetoclax in acute myeloid leukemia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6564.

Abstract 7218: Venetoclax triggers apoptosis and augments the effectiveness of doxorubicin against acute myeloid leukemia cells

Abstract Acute myeloid leukemia (AML) is a hematologic malignancy characterized by the clonal proliferation of immature blast cells in the peripheral blood and bone marrow. AML is the second most common type of childhood leukemia, and 50% to 60% of relapses occur within the first year of diagnosis. Chemotherapy side effects and resistance are becoming major clinical issues. Although anthracyclines are one of the most commonly used induction regimens for children with AML in the United States, clinicians avoid them due to adverse effects and clinical resistance issues. To address this clinical issue, we are looking for a novel AML approach to boost the usage of anthracyclines. Since Bcl-2 protein overexpression in AML is related to uncontrolled growth, poor prognosis, and chemoresistance. Multiple clinical trials have suggested combining venetoclax (a selective Bcl-2 inhibitor) with well-established medicines to boost efficacy and overcome resistance. We suggest that inhibiting Bcl-2 is a feasible strategy for increasing the use of anthracycline medicines. We proposed combining doxorubicin and venetoclax as an alternative approach for AML patients. In a panel of three AML cell lines, Kusami-1, U937, and THP-1, our western blot revealed that Kusami-1 had the highest expression of Bcl-2 proteins. Surprisingly, venetoclax causes Kusami-1 cell death and increases the efficacy of doxorubicin in a dose-dependent manner, suggesting that utilizing a lower clinical standard dose may avoid major adverse effects such as cardiotoxicity. Furthermore, the Annexin V Apoptosis Detection Kit indicated that venetoclax coupled with doxorubicin synergistically promoted total apoptosis in Kusami-1 cells. The combination medication shown promising and synergistic in vitro anti-leukemic action against AML cell lines and represents a potentially viable treatment option for AML patients. Future research will use the combination approach in AML cell lines, as well as in patient samples and in vivo experiments. Citation Format: Osama Aloudat, Omar S. Al Odat, Tulin Budak-Alpdogan, Subash Jonnalagadda, Yong Chen, Manoj Pandey. Venetoclax triggers apoptosis and augments the effectiveness of doxorubicin against acute myeloid leukemia cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7218.

Abstract 2827: Characterization of acute myeloid leukemia PDX models with hotspot gene mutations for therapeutic evaluation

Abstract Introduction: Acute myeloid leukemia (AML) is the most common acute type of leukemia in adults characterized by chromosomal abnormalities and gene mutations. While inhibitors have shown promise targeting FLT3 mutations, resistance to these inhibitors can emerge. Similarly, inhibitors targeting IDH1 and IDH2 mutations showed promise, yet the emergence of drug resistance poses a significant challenge. In this study, a panel of AML PDX models with multiple gene alterations was established to support the development of new therapies. Methods: The systemic AML PDX models were established using patients’ peripheral blood (PB) or bone morrow (BM) injected intravenously and expanded in vivo by using splenic tumor cells. One AML PDX model derived from patient skin was established subcutaneously. Expression of human CD45+ in PB cells for systemic models or tumor volume for the subcutaneous model was used to monitor the tumor burden. Leukemic loads (hCD45+ cells) were measured in PB, spleen (SP), and BM. Tumors were categorized following tumor immunophenotyping, histology, and RNA sequencing/Whole Exome Sequencing. For in vivo efficacy studies, animals were grouped 3-5 weeks after systemic tumor cells inoculation and treated with AC220 (1, 2 or 10 mg/kg, p.o., QD), Cytarabine (Ara-c, 2mg/kg, i.p., QD), 5-azacytidine (2mg/kg, i.p., QD), Sorafenib (10mg/kg, i.p., QD) and Gilteritinib (10 or 30mg/kg, p.o., QD). Results: Nine systemic and one subcutaneous AML PDX models carrying hotspot mutations (e.i. FLT3-ITD or TKD, IDH1-R132H and IDH2-R140Q) were established, showing comparable features to the clinic. Systemic AM8231 PDX model harboring FLT3-ITD mutation treated with AC220, a type II FLT3i, showed significant tumor burden reduction in PB at different time points and in SP and BM at termination, as well as a survival increase. Similarly in systemic model AM7577 with FLT3-ITD mutation treated with AC220, significant tumor burden reduction in PB was observed. Whereas using systemic model AM9626 (model with Sorafenib pretreatment history) with coexisting-FLT3-ITD/D835H TKD mutation, no significant efficacy was observed with AC220i, suggesting a FLT3-TKD mediated resistance mechanism. To overcome the resistance, Gilteritinib, a type I FLT3i, was tested in AM9626 and showed significant reduction of hCD45+ cells in PB compared to the control group, even at a lowest dose. As model AM9626 PDX also carries IDH1 mutation, the level of serum 2-HG correlated with the tumor burden. The functional effect of IDH1 inhibitor on the tumor inhibition and 2-HG level is under investigation. Conclusion: The results presented in this study showed the establishment of a panel of AML PDX models, including different subtypes and genomic features reflecting the clinic. Those models will support the preclinical evaluation of new treatments or combination modalities as well as a better understanding of drug resistance mechanisms. Citation Format: Qingzhi Liu, Jinxi Wang, Jinping Liu, Likun Zhang, Ludovic Bourre, Jingjing Wang. Characterization of acute myeloid leukemia PDX models with hotspot gene mutations for therapeutic evaluation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2827.

An Interpretable Machine Learning Framework for Rare Disease: A Case Study to Stratify Infection Risk in Pediatric Leukemia.

Background: Datasets on rare diseases, like pediatric acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), have small sample sizes that hinder machine learning (ML). The objective was to develop an interpretable ML framework to elucidate actionable insights from small tabular rare disease datasets. Methods: The comprehensive framework employed optimized data imputation and sampling, supervised and unsupervised learning, and literature-based discovery (LBD). The framework was deployed to assess treatment-related infection in pediatric AML and ALL. Results: An interpretable decision tree classified the risk of infection as either "high risk" or "low risk" in pediatric ALL (n = 580) and AML (n = 132) with accuracy of ∼79%. Interpretable regression models predicted the discrete number of developed infections with a mean absolute error (MAE) of 2.26 for bacterial infections and an MAE of 1.29 for viral infections. Features that best explained the development of infection were the chemotherapy regimen, cancer cells in the central nervous system at initial diagnosis, chemotherapy course, leukemia type, Down syndrome, race, and National Cancer Institute risk classification. Finally, SemNet 2.0, an open-source LBD software that links relationships from 33+ million PubMed articles, identified additional features for the prediction of infection, like glucose, iron, neutropenia-reducing growth factors, and systemic lupus erythematosus (SLE). Conclusions: The developed ML framework enabled state-of-the-art, interpretable predictions using rare disease tabular datasets. ML model performance baselines were successfully produced to predict infection in pediatric AML and ALL.

STING-activating cyclic dinucleotide-manganese nanoparticles evoke robust immunity against acute myeloid leukemia

Acute myeloid leukemia (AML) is one of the most common types of leukemia in adults with a 5-year survival rate of 30.5%. These poor patient outcomes are attributed to tumor relapse, stemming from ineffective innate immune activation, T cell tolerance, and a lack of immunological memory. Thus, new strategies are needed to activate innate and effector immune cells and evoke long-term immunity against AML. One approach to address these issues is through Stimulator of Interferon Genes (STING) pathway activation, which produces Type I Interferons (Type I IFN) critical for innate and adaptive immune activation. Here, we report that systemic immunotherapy with a lipid-based nanoparticle platform (CMP) carrying Mn2+ and STING agonist c-di-AMP (CDA) exhibited robust anti-tumor efficacy in a mouse model of disseminated AML. Moreover, CMP immunotherapy combined with immune checkpoint blockade against cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) elicited robust innate and adaptive immune activation with enhanced cytotoxic potential against AML, leading to extended animal survival after re-challenge with AML. Overall, this CMP combination immunotherapy may be a promising approach against AML and other disseminated cancer.

Severe Sepsis During Treatment for Childhood Leukemia and Sequelae Among Adult Survivors

Children undergoing treatment for leukemia are at increased risk of severe sepsis, a dysregulated immune response to infection leading to acute organ dysfunction. As cancer survivors, they face a high burden of long-term adverse effects. The association between sepsis during anticancer therapy and long-term organ dysfunction in adult survivors of childhood cancer has not been examined. To determine whether severe sepsis during therapy for leukemia in childhood is associated with subsequent chronic health conditions in adult survivors. This cohort study included 644 adult survivors of childhood leukemia who were diagnosed between January 1, 1985, and July 19, 2010, and participated in the St Jude Lifetime Cohort Study. Participants were excluded if they received hematopoietic cell transplant or had relapsed leukemia. Data collection ended June 30, 2017. Data were analyzed from July 1, 2020, to January 5, 2024. Severe sepsis episodes, defined according to consensus criteria as septic shock, acute respiratory distress syndrome, or multiorgan dysfunction associated with infection occurring during anticancer therapy, were abstracted by medical record review for all participants. Common Terminology Criteria for Adverse Events-defined chronic health condition outcomes were independently abstracted. Associations between sepsis and cumulative incidence of chronic health conditions (eg, cardiovascular, pulmonary, kidney, neurological, and neurocognitive outcomes) were compared by adjusted hazard ratios from Cox proportional hazards logistic regression. Inverse propensity score weighting was used to adjust for potential confounders, including age, year of diagnosis, and leukemia type. The study sample consisted of 644 adult survivors of pediatric leukemia (329 women [51.1%] and 315 men [48.9%]; including 56 with a history of acute myeloid leukemia and 585 with a history of acute lymphoblastic leukemia) who were most recently evaluated at a median age of 24.7 (IQR, 21.2-28.3) years at a median time after leukemia diagnosis of 17.3 (IQR, 13.7-21.9) years. Severe sepsis during treatment of acute childhood leukemia occurred in 46 participants (7.1%). Participants who experienced severe sepsis during treatment were more likely to develop moderate to severe neurocognitive impairment (29 of 46 [63.0%] vs 310 of 598 [51.8%]; adjusted hazard ratio, 1.86 [95% CI, 1.61-2.16]; P < .001) significantly affecting attention, executive function, memory and visuospatial domains. Sepsis was not associated with long-term risk of cardiovascular, pulmonary, kidney, or neurological chronic health conditions. In this cohort study of long-term outcomes in survivors of pediatric leukemia, severe sepsis during anticancer therapy for leukemia was associated with a selectively increased risk for development of serious neurocognitive sequelae. Efforts to reduce the effects of anticancer therapy on long-term function and quality of life in survivors might include prevention of severe sepsis during therapy and early detection or amelioration of neurocognitive deficits in survivors of sepsis.

The Screening of microRNAs in Chronic Myeloid Leukemia: A Clinical Evaluation.

Chronic myeloid leukemia (CML) is a type of leukemia whose main genetic marker is the reciprocal translocation that leads to the production of the BCR::ABL1 oncoprotein. The expression of some genes may interfere with the progression and development of leukemias. MicroRNAs are small non-coding RNAs that have the potential to alter the expression of some genes and may be correlated with some types of leukemia and could be used as biomarkers in the diagnosis and prognosis of patients. Therefore, this project carried out an analysis of microRNA-type plasma biomarkers in patients with chronic myeloid leukemia at unique points, including follow-up analysis of patients from the Erasto Gaertner Hospital. 35 microRNAs were analyzed in different cohorts. Inside those groups, 70 samples were analyzed at unique points and 11 patients in a follow-up analysis. Statistically different results were found for microRNA-7-5p, which was found to be upregulated in patients with high expression of the BCR::ABL1 transcript when compared to healthy controls. This microRNA also had evidence of behavior related to BCR::ABL1 when analyzed in follow-up, but strong evidence was not found. In this way, this work obtained results that may lead to manifestations of a relationship between miR-7-5p and chronic myeloid leukemia, and evaluations of possible microRNAs that are not related to this pathology.

Combined Delivery of miR-15/16 through Humanized Ferritin Nanocages for the Treatment of Chronic Lymphocytic Leukemia.

Chronic lymphocytic leukemia (CLL) is a widespread type of leukemia that predominantly targets B lymphocytes, undermining the balance between cell proliferation and apoptosis. In healthy B cells, miR-15/16, a tandem of microRNAs, functions as a tumor suppressor, curbing the expression of the antiapoptotic B cell lymphoma 2 protein (Bcl-2). Conversely, in CLL patients, a recurring deletion on chromosome 13q14, home to the miR15-a and miR16-1 genes, results in Bcl-2 overexpression, thereby fostering the onset of the pathology. In the present research, a novel approach utilizing humanized ferritin-based nanoparticles was employed to successfully deliver miR15-a and miR-16-1 into MEG01 cells, a model characterized by the classic CLL deletion and overexpression of the human ferritin receptor (TfR1). The loaded miR15-a and miR16-1, housed within modified HumAfFt, were efficiently internalized via the MEG01 cells and properly directed into the cytoplasm. Impressively, the concurrent application of miR15-a and miR16-1 demonstrated a robust capacity to induce apoptosis through the reduction in Bcl-2 expression levels. This technology, employing RNA-loaded ferritin nanoparticles, hints at promising directions in the battle against CLL, bridging the substantial gap left by traditional transfection agents and indicating a pathway that may offer hope for more effective treatments.

BATF promotes extramedullary infiltration through TGF-β1/Smad/MMPs axis in acute myeloid leukemia.

Acute myeloid leukemia (AML) is one of the most prevalent types of leukemia and is challenging to cure for most patients. Basic Leucine Zipper ATF-Like Transcription Factor (BATF) has been reported to participate in the development and progression of numerous tumors. However, its role in AML is largely unknown. In this study, the expression and prognostic value of BATF were examined in AML. Our results demonstrated that BATF expression was upregulated in AML patients, which was significantly correlated with poor clinical characteristics and survival. Afterward, functional experiments were performed after knocking down or overexpressing BATF by transfecting small interfering RNAs and overexpression plasmids into AML cells. Our findings revealed that BATF promoted the migratory and invasive abilities of AML cells in vitro and in vivo. Moreover, the target genes of BATF were searched from databases to explore the binding of BATF to the target gene using ChIP and luciferase assays. Notably, our observations validated that BATF is bound to the promoter region of TGF-β1, which could transcriptionally enhance the expression of TGF-β1 and activate the TGF-β1/Smad/MMPs signaling pathway. In summary, our study established the aberrantly high expression of BATF and its pro-migratory function via the TGF-β1-Smad2/3-MMP2/9 axis in AML, which provides novel insights into extramedullary infiltration of AML.

A brief look at genetic and environmental risk factors of leukemia and its preventions and treatment

Leukemia, the most diagnosed cancer in children and adolescents, is the malignancy of white blood cells that begins in hematopoietic stem cells in the bone marrow and brings severe impact to the lymphatic system in which ALL, AML, CML, and CLL are diagnosed most commonly. Risk factors of leukemia is highly evaluated in recent studies and treatments for leukemia have shown great advance too. However, the knowledge to public about leukemia, its risk factors, and its treatments is still limited. This article aims to introduce different types of leukemia including ALL, AML, CLL, CML, analyze genetic and environmental risk factors of leukemia, and describe some of its treatments such as chemotherapy, radiation therapy, and bone marrow transplantation in detail. To avoid and address mechanisms of resistance that arise during leukemia therapy, it is crucial to adopt a comprehensive strategy to the combination of medicine, to manage risk factors to the public, to make lifestyle interventions, to develop more advanced therapies, and to gain a deeper understanding of mechanism of resistance.

An efficient decision support system for leukemia identification utilizing nature-inspired deep feature optimization.

In the field of medicine, decision support systems play a crucial role by harnessing cutting-edge technology and data analysis to assist doctors in disease diagnosis and treatment. Leukemia is a malignancy that emerges from the uncontrolled growth of immature white blood cells within the human body. An accurate and prompt diagnosis of leukemia is desired due to its swift progression to distant parts of the body. Acute lymphoblastic leukemia (ALL) is an aggressive type of leukemia that affects both children and adults. Computer vision-based identification of leukemia is challenging due to structural irregularities and morphological similarities of blood entities. Deep neural networks have shown promise in extracting valuable information from image datasets, but they have high computational costs due to their extensive feature sets. This work presents an efficient pipeline for binary and subtype classification of acute lymphoblastic leukemia. The proposed method first unveils a novel neighborhood pixel transformation method using differential evolution to improve the clarity and discriminability of blood cell images for better analysis. Next, a hybrid feature extraction approach is presented leveraging transfer learning from selected deep neural network models, InceptionV3 and DenseNet201, to extract comprehensive feature sets. To optimize feature selection, a customized binary Grey Wolf Algorithm is utilized, achieving an impressive 80% reduction in feature size while preserving key discriminative information. These optimized features subsequently empower multiple classifiers, potentially capturing diverse perspectives and amplifying classification accuracy. The proposed pipeline is validated on publicly available standard datasets of ALL images. For binary classification, the best average accuracy of 98.1% is achieved with 98.1% sensitivity and 98% precision. For ALL subtype classifications, the best accuracy of 98.14% was attained with 78.5% sensitivity and 98% precision. The proposed feature selection method shows a better convergence behavior as compared to classical population-based meta-heuristics. The suggested solution also demonstrates comparable or better performance in comparison to several existing techniques.

The Association between Single Nucleotide Polymorphisms rs1042522 and rs1642785 in the TP53 gene and Acute Myeloid leukemia in a sample of the Baghdad/ Iraq population

يمثل سرطان الدم النخاعي الحاد (AML) أكثر أنواع سرطان الدم الحاد انتشارًا بين البالغين تصل نسبته 80% من جميع الحالات. الجين المثبط للورم TP53 هو جين تمت دراسته بشكل متكرر في مرض السرطان .والطفرات في هذا الجين تسبب ما يقارب 50% من الامراض السرطانية. هدفت هذه الدراسة إلى تقييم العلاقة بين اثنين من تعدد أشكال النوكليوتيدات المفردة في جين TP53: rs1042522 ، rs1642785 ومجموعة من المرضى العراقيين الذين يعانون من التشخيص الاولي لسرطان الدم النخاعي الحاد. جمعت عينات الدم من ستين مريضاً 26 ذكور و 34 أناث وستين عينة سيطرة 26 ذكور و 34 أناث متوافقين في الجنس والعمر والعرق. تم استخلاص الحمض النووي الجيني من عينات الدم المجمدة بالكامل باستخدامEasy Pure® Blood Genomic Kit . ثم تم قياس النقاوة والتركيز باستخدام مقياس الطيف الضوئي Nano drop NAS-99. حيث تراوحت قراءات التركيز بين (7-55 نانوغرام / ميكرولتر) وتراوحت النقاوة بين 1.78 - 1.9 تم استخدام تقنيةreal time PCR (High resolution melt (HRM للكشف عن تعدد اشكال النيوكليوتيدات المفردة و كانت تكرارات النمط الجيني لجين TP53 متوافقة مع توازن هاردي-واينبرغ مع وجود فروق معنوية ذات دلالة إحصائية p≤0.05 بين الأنماط الجينية لمجموعة السيطرة والمرضى. كان تكرار النمط الجيني rs1042522 مختلفًا بشكل كبير بين المرضى وافراد السيطرة p = 0.0001، وكان المشاركون الذين لديهم النمط الوراثي GA أكثر عرضة للإصابة بسرطان الدم النخاعي الحاد OR=7.8, 95% CI 3.2–18.4, p = 0.0001. بالإضافة الى تكرار النمط الجيني rs1642785 مختلفًا بشكل كبير بين المرضى و افراد السيطرة p=0.002 والذين يحملون النمط الجيني GA أكثر عرضة للإصابة بسرطان الدم النخاعي الحاد OR=3.5, 95% CI 1.5–8.12, p=0.002.

Outcomes of intracranial hemorrhage in critically ill patients with acute leukemia: Results of a retrospective cohort study

BackgroundAdmission to the intensive care unit (ICU) is frequently required for patients with acute leukemia (AL) because of life-threatening complications such as intracranial hemorrhage (IH). In this study, we evaluated the impact of IH on survival and neurological outcomes in this population. MethodsThis was a single-center retrospective cohort study including adult patients with AL requiring ICU admission and experiencing IH between 2002 and 2019 at Saint Louis Hospital. Leukemia type was determined according to the French–American–British classification. Brain imaging (either computed tomography or magnetic resonance imaging) was available for all the patients. The primary endpoint of the study was to describe the clinical and biological characteristics and evaluate the mortality and neurological outcome of patients hospitalized in the ICU with newly diagnosed AL and IH. The secondary endpoint was to identify predictive factors of IH in these patients. ResultsThirty-five patients with AL were included, median age of the patients was 59.00 (interquartile range [IQR]: 36.00–66.00) years. Twenty-nine patients (82.9%) had acute myeloid leukemia, including 12 patients with acute promyelocytic leukemia. Thrombocytopenia was constant, and 48.5% of patients had disseminated intravascular coagulation (DIC). At ICU admission, the median Sequential Organ Failure Assessment score was 5 (IQR: 3–9). The median time between AL onset and IH was 2.0 (IQR: 0.0–9.5) days. The ICU and hospital mortality rates were 60.0% (n =21) and 65.7% (n=23), respectively. In univariate analysis, mechanical ventilation and stupor were associated with mortality, but DIC and acute promyelocytic leukemia were not. Upon multivariate analysis, stupor or coma was the only factor significantly associated with a poor outcome (odds ratio = 8.56, 95 % confidence interval: 2.40 to 30.46). ConclusionIH is associated with a high mortality rate in AL patients, with stupor or coma at the onset of intracranial bleeding being independently associated with poor outcomes.

Prognostication in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in Western countries. CLL is a highly heterogeneous disease: some patients may never require therapy and others relapse several times after different therapeutic strategies. Therefore, in CLL, prognostic markers are essential to capture high-risk patients for different clinical endpoints including early treatment requirement, early progression after BTK or BCL2 inhibitors and Richter transformation. In early stage CLL, different biological and clinical biomarkers have been identified to predict time to treatment requirement that could be used to identify the most appropriate population for early intervention clinical trial. However, at the moment, the standard of care for early stage CLL remains watch & wait since no survival benefit has been identified in clinical trials with chemoimmunotherapy and with BTK inhibitors. In patients requiring treatment TP53 disruptions identify high-risk patients who benefit the most from long-term continuous therapy with BTKi. On the opposite side of the spectrum, IGHV mutated patients devoid of TP53 disruption benefit the most from fixed-duration therapy with venetoclax-obinutuzumab. In between, the highly heterogenous subgroup of patients with IGHV unmutated genes represents the group in which further efforts are needed to identify additional prognostic biomarkers aimed at selecting patients who can benefit from fixed-duration and patients who can benefit from long term BTKi therapy. In the context of the aggressive transformation of CLL, namely Richter syndrome, the clonal relationship to the CLL counterpart represents the strongest prognostic biomarker. Clonally related Richter syndrome still represents an unmet clinical need which requires further efforts to identify new therapeutic strategies.

Assessment of Y chromosome copy number alterations in non-neoplastic and neoplastic leukocytes of male dogs

The loss of the Y chromosome (ChrY), also known as LOY, is a common genetic alteration observed in men. It occurs in non-neoplastic cells as an age-related change as well as in neoplastic cells of various cancer types. While well-documented in humans, LOY has not been extensively studied in non-human mammals. In this study, we developed simple digital PCR-based assays to assess the copy number of ChrY relative to the X chromosome (ChrX) and chromosome 8 (Chr8) to evaluate ChrY numerical alterations in male canine DNA specimens. Using these assays, we analyzed non-neoplastic leukocytes from 162 male dogs without hematopoietic neoplasia to investigate the occurrence of age-related LOY in non-neoplastic leukocytes. Additionally, we examined 101 tumor DNA specimens obtained from male dogs diagnosed with various types of lymphoma and leukemia to determine whether copy number alterations of the ChrY occur in canine hematopoietic cancers. Analysis of the 162 non-neoplastic leukocyte DNA specimens from male dogs of varying ages revealed a consistent ∼1:1 ChrY:ChrX ratio. This suggests that age-related LOY in non-neoplastic leukocytes is rare or absent in dogs. Conversely, a decreased or increased ChrY:ChrX ratio was detected in canine neoplastic leukocytes at varying frequencies across different canine hematopoietic malignancies (P = 0.01, Fisher's exact test). Notably, a higher incidence of LOY was observed in more aggressive cancer types. To determine if this relative LOY to ChrX was caused by changes in ChrY or ChrX, we further analyzed their relative copy numbers using Chr8 as a reference. Loss of ChrX relative to Chr8 was found in 21% (9/41) of B-cell lymphomas and 6% (1/18) of non-T-zone/high-grade T-cell lymphomas. In contrast, a subset (29%, 4/14) of T-cell chronic lymphocytic leukemia showed gain of ChrX relative to Chr8. Notably, no relative LOY to Chr8 was detected indolent hematopoietic cancers such as T-zone lymphoma (0/9) and chronic lymphocytic leukemia of B-cell (0/11) and T-cell origins (0/14). However, relative LOY to Chr8 was present in more aggressive canine hematopoietic cancers, with incidences of 24% (10/41) in B-cell lymphoma, 44% (8/18) in non-T-zone/high-grade T-cell lymphoma, and 75% (6/8) in acute leukemia. This study highlights both similarities and differences in LOY between human and canine non-neoplastic and neoplastic leukocytes. It underscores the need for further research into the role of ChrY in canine health and disease, as well as the significance of LOY across various species.

Alterations in Genome Organization in Lymphoma Cell Nuclei due to the Presence of the t(14;18) Translocation.

Chromosomal rearrangements have been shown to alter genome organization, consequently having an impact on gene expression. Studies on certain types of leukemia have shown that gene expression can be exacerbated by the altered nuclear positioning of fusion genes arising from chromosomal translocations. However, studies on lymphoma have been, so far, very limited. The scope of this study was to explore genome organization in lymphoma cells carrying the t(14;18)(q32;q21) rearrangement known to results in over-expression of the BCL2 gene. In order to achieve this aim, we used fluorescence in situ hybridization to carefully map the positioning of whole chromosome territories and individual genes involved in translocation in the lymphoma-derived cell line Pfeiffer. Our data show that, although there is no obvious alteration in the positioning of the whole chromosome territories, the translocated genes may take the nuclear positioning of either of the wild-type genes. Furthermore, the BCL2 gene was looping out in a proportion of nuclei with the t(14;18) translocation but not in control nuclei without the translocation, indicating that chromosome looping may be an essential mechanism for BCL2 expression in lymphoma cells.

Recent Advances in Signaling Pathways and Kinase Inhibitors for Leukemia Chemotherapy.

Leukemia is a malignant clonal disease of hematopoietic stem cells, which accounts for about 3% of the total incidence of tumors and is particularly prevalent among children and adolescents. It mainly includes four types of leukemia, namely ALL, AML, CLL, and CML, which are often aggressive and challenging diseases to treat. Several signaling pathways are dysregulated in almost all types of leukemia, such as JAK, PI3K, and MAPK, and others are dysregulated in specific types of leukemia, like Wnt/β-catenin, Hedgehog, FLT3, Bcr-Abl, and so on. Many efforts have been devoted to developing small molecule inhibitors targeting protein kinases involved in leukemia-related signaling pathways. In this review, we focus on the study of signaling pathways and protein kinases that developed as targets of anti-leukemia drug therapy and report the research progress of relevant small molecule kinase inhibitors over the last five years.

Proteolysis Targeting Chimera Degraders of the METTL3-14 m6A-RNA Methyltransferase.

Methylation of adenine N6 (m6A) is the most frequent RNA modification. On mRNA, it is catalyzed by the METTL3-14 heterodimer complex, which plays a key role in acute myeloid leukemia (AML) and other types of blood cancers and solid tumors. Here, we disclose the first proteolysis targeting chimeras (PROTACs) for an epitranscriptomics protein. For designing the PROTACs, we made use of the crystal structure of the complex of METTL3-14 with a potent and selective small-molecule inhibitor (called UZH2). The optimization of the linker started from a desfluoro precursor of UZH2 whose synthesis is more efficient than that of UZH2. The first nine PROTAC molecules featured PEG- or alkyl-based linkers, but only the latter showed cell penetration. With this information in hand, we synthesized 26 PROTACs based on UZH2 and alkyl linkers of different lengths and rigidity. The formation of the ternary complex was validated by a FRET-based biochemical assay and an in vitro ubiquitination assay. The PROTACs 14, 20, 22, 24, and 30, featuring different linker types and lengths, showed 50% or higher degradation of METTL3 and/or METTL14 measured by Western blot in MOLM-13 cells. They also showed substantial degradation on three other AML cell lines and prostate cancer cell line PC3.

Addressing a Pre-Clinical Pipeline Gap: Development of the Pediatric Acute Myeloid Leukemia Patient-Derived Xenograft Program at Texas Children's Hospital at Baylor College of Medicine.

The survival rate of pediatric acute myeloid leukemia (pAML) is currently around 60%. While survival has slowly increased over the past few decades, the development of novel agents likely to further improve survival for this heterogeneous patient population has been limited by gaps in the pAML pre-clinical pipeline. One of the major hurdles in evaluating new agents for pAML is the lack of pAML patient-derived xenograft (PDX) models. Unlike solid tumors and other types of leukemias, AML is notoriously hard to establish in mouse models, likely due in part to the need for specific human microenvironment elements. Our laboratory at TCH/BCM addressed this gap by establishing a systematic PDX workflow, leveraging advanced immunodeficient hosts and capitalizing on our high volume of pAML patients and close coordination between labs and clinical sections. Patients treated at TCH are offered the chance to participate in specimen banking protocols that allow blood and bone marrow collection as well as the collection of relevant clinical data. All patients who consent and have samples available are trialed for PDX development. In addition, samples from the Children's Oncology Group (COG) are also trialed for PDX generation. Serially transplanting PDX models are validated using short tandem repeat (STR) and characterized using both targeted DNA/RNA next generation sequencing and RNAseq. As of March 2023, this systematic approach has resulted in 26 serially transplanting models. Models have been shared with requesting labs to facilitate external pAML pre-clinical studies. Available PDX models can be located through the BCM PDX Portal. We expect our growing PDX resource to make a significant contribution to expediting the testing of promising novel therapeutics for pAML.

Evaluation of the Findings of Peripheral Blood Smear, Bone Marrow Aspiration and Biopsy, Iron Storage, and Immunophenotype in Patients with Chronic Lymphocytic Leukemia.

Chronic lymphocytic leukemia (CLL) is one of the most common types of leukemia in adults with various signs, symptoms, and types of progression. In this study, we have investigated the frequency and correlation of laboratory findings including peripheral blood smear, bone marrow aspiration and biopsy, and cellular immunophenotyping in CLL patients. In this cross-sectional and retrospective study, the laboratory information of all 161 patients with definite diagnoses of CLL was extracted, and the frequency and correlation between different laboratory data were analyzed by descriptive statistics methods and Jamovi software version 2022. Demographic factors such as age and gender, and laboratory factors such as anemia, thrombocytopenia, white blood cell count, percentage of lymphocytes, and patterns of bone marrow involvement were evaluated for 161 patients. There was a significant relationship between the bone marrow iron storage and the percentage of FMC7 marker expression with the percentage of atypical lymphocytes in the peripheral blood. Chronic lymphocytic leukemia, a prevalent form of leukemia associated with substantial mortality and morbidity, can be detected through a range of diagnostic techniques. Analyzing the results of these diagnostic tests and examining the prevalence of these indicators in patients afflicted with the condition can prove highly beneficial for prompt disease diagnosis, and prognosis determination among affected individuals.