BCR-ABL Fusion Gene Research Articles

Self-assembled Human Serum Protein-based Core-shell Nanoparticles to inhibit key oncogenic signalling in Drug-Resistant Leukemia

Simultaneous inhibition of multiple oncogenic signaling pathways is crucial for managing refractory cancers. This study introduces two unique core-shell nanoparticle (CS-NP) systems crafted from natural proteins that simultaneously target two crucial oncogenic pathways in refractory chronic myeloid leukemia (CML). Molecular analysis of approximately 14 refractory CML patients identified resistance to the standard treatment drug, imatinib, attributed to the overex-pression of the STAT5-transferrin pathway alongside the classic BCR-ABL fusion gene. To address this, we developed two dual-drug-loaded core-shell nanoparticles: (a) CS-NP1: Protamine sulfate nanocores carrying BCR-ABL siRNA and an albumin shell loaded with the STAT5 in-hibitor sorafenib, denoted as (PS-siRNA)-(Tf-Soraf) CS-NP; (b) CS-NP2: features a second-generation BCR-ABL inhibitor, dasatinib, in the albumin nanocore, and sorafenib in the transferrin nanoshell, labeled as (nAlb-Dasa)-(Tf-Soraf). We hypothesized that these dual-drug-loaded CS-NPs would effectively target both BCR-ABL and STAT5 pathways, with the transferrin nanoshell aiding in precise delivery to refractory CML cells overexpressing TfR1 due to STAT5 activity. Initial evaluations in drug resistant CML cell lines and patient-derived cells demonstrated significant cytotoxicity. Remarkably, even patients with BCR-ABL oncogene mutations displayed over 95% cytotoxicity with the CS-NPs. Furthermore, in vivo testing on a human xeno-graft model with a BCR-ABL+/+/STAT5+/+/TfR+/+ phenotype showcased a strong anti-tumor response. These results underscore the potential of a molecular-diagnosis-based rational design approach for protein-protein core-shell nanoparticles to simultaneously inhibit multiple oncogenic pathways, thereby overcoming resistance to targeted molecular therapies.

HDAC2-miR183-5p Epigenetic Circuit Contributes to the Growth of Philadelphia Chromosome-Positive B-cell Acute Lymphoblastic Leukemia via PTEN/AKT and c-MYC Signaling Pathway.

Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia (Ph(+)B-ALL) is a hematological malignancy with a poor prognosis. Epigenetic abnormalities, especially abnormal histone acetylation and microRNAs (miRNAs) dysregulation, are a group of epigenetic patterns that contribute to leukemia progression. However, their regulatory mechanisms in Ph(+)B-ALL have not been fully elucidated. In this study, we identified that miR-183-5p is significantly downregulated in Ph(+)B-ALL and associated with poor prognosis. Moreover, we found that the BCR-ABL fusion gene is a key target gene of miR-183-5p. MiR-183-5p directly targets BCR-ABL gene and induces cell apoptosis via PTEN/AKT and c-MYC signaling pathways. In addition, histone deacetylase inhibitor (HADCi) could mitigate the suppressive effects of HDAC2 on miR-183-5p by promoting promoter acetylation, thereby enhancing cell apoptosis. In conclusion, our results indicate that miR-183-5p is a potential biomarker and suggest that a novel "HDAC2-miR-183-5p epigenetic circuitry regulation" may be involved in the pathogenesis of Ph(+)B-ALL. Taken together, These findings provide new insights into the design of promising molecular-targeted drugs for Ph(+)B-ALL.

Establishment of genomic RNA reference materials for BCR-ABL1 P210 measurement.

Quantitation of BCR-ABL1 with thequantitative reverse transcriptase polymerase chain reaction (RT-PCR) is very important in monitoring chronic myeloid leukemia (CML), which relies on an RNA reference material. A genomic RNA reference material (RM) containing the BCR-ABL1 P210 fusion mutation was developed, and an absolute quantitative method based on one-step reverse transcription digital PCR (RT-dPCR) was established for characterizing the RM. The proposed dPCR method demonstrates high accuracy and excellent analytical sensitivity, as shown by the linear relationship (0.94 < slope < 1.04, R2≧0.99) between the measured and nominal values of b2a2, b3a2, and ABL1-ref within the dynamic range (104-101 copies/reaction). Homogeneity and stability assessment based on dPCR indicated that the RM was homogeneous and stable for 24months at -80°C. The RM was used to evaluate inter-laboratory reproducibility in eight different laboratories, demonstrating that participating laboratories could consistently produce copy concentrations of b3a2 and ABL1-ref, as well as the BCR-ABL1/ABL1 ratio (CV < 2.0%). This work suggests that the RM can be employed in establishing metrological traceability for detecting mutations in the BCR-ABL1 fusion gene, as well as in quality control for testing laboratories.

Insights into existing and futuristic treatment approach for chronic myeloid leukaemia.

Oncogenes play a crucial part in human cancer development, and when particular drugs obstruct the proteins produced by these oncogenes, the tumoural process can be ceased. For instance, in chronic myeloid leukaemia (CML), all pathological traits are associated with a single oncogene, BCR-ABL1. CML is a triphasic cancerous disorder of haematopoietic stem cells, marked by a balanced translocation between chromosomes 9 and 22, leading to the genesis of a Philadelphia chromosome encompassing the BCR-ABL1 fusion gene. This fusion oncogene further produces a constitutive active tyrosine kinase protein, enhancing the downstream signalling pathways and constitutes cancer. The treatment for CML has been entirely altered from chemotherapy and immunotherapy to targeted therapy with the emergence of tyrosine kinase inhibitors (TKIs) which inhibit BCR-ABL1 kinase activity. However, the inhibitory mechanism of TKIs is constrained by BCR-ABL1 dependent and independent resistance mechanisms, prompting the exploration of novel therapeutics through extensive clinical trials to develop next-generation drugs with enhanced potency. The persistent challenges posed by CML have motivated researchers to seek innovative strategies for its eradication, such as the application of the genome editing tool CRISPR/Cas9. This review provides insights into existing CML diagnoses, treatment modalities, resistance mechanisms, drugs under trial phases and new potential therapeutic drugs. Furthermore, the review looks ahead to a visionary perspective wherein the CRISPR/Cas9 approach holds the potential to evolve into a prospective curative measure for CML.

Risk Prediction and Risk Factors of Thrombotic/Bleeding Events in Patients with Myeloproliferative Neoplasm

To analyze the clinical characteristics and occurrence of thrombotic/bleeding events of patients with myeloproliferative neoplasm (MPN), and explore the main influencing factors, and create a risk prediction. The clinical data of 126 MPN patients with BCR-ABL fusion gene negative in the Department of Hematology of Gansu Provincial Hospital from January 2016 to September 2021 were collected, and their clinical characteristics, occurrence of thrombotic/bleeding events and main influencing factors were analyzed and summarized retrospectively. Then, a risk prediction model for thrombotic/bleeding events in MPN patients was constructed. Among 126 MPN patients, 50 patients (39.7%) had experienced thrombotic/bleeding events, including 44 patients (34.9%) with thrombotic events and 6 patients (4.8%) with bleeding events. Among thrombotic diseases, cerebral thrombosis was the most common (23/44, 52.3%), followed by 9 cases of limb artery thrombosis mainly characterized by finger and toe tip artery ischemia, occlusion and gangrene (9/44, 20.5%). Bleeding events included intracerebral hemorrhage and gastrointestinal hemorrhage. Univariate analysis showed that hypertension, hyperhomocysteinemia, white blood cell (WBC) ≥10×109/L, hematocrit (HCT) ≥49%, platelet (PLT) ≥600×109/L and JAK2V617F gene mutation were risk factors for thrombotic/bleeding events in MPN patients, while CALR gene mutation was a protective factor. Multivariate analysis showed that hypertension and PLT≥600×109/L were independent risk factors for thrombotic/bleeding events in MPN patients. The goodness of fit of the constructed risk prediction model was 0.872, and the area under the ROC curve was 0.838. The model was validated with clinical data, the sensitivity, specificity and accuracy was 78.85%, 87.83% and 84.13%, respectively . The risk of thrombotic/bleeding events in MPN patients with high WBC count, hypertension and hyperhomocysteinemia is higher. Controlling hypertension and hyperhomocysteinemia and reducing WBC and PLT counts are helpful to prevent thrombotic/bleeding events and improve the life quality of patients.

[Artículo traducido] Asciminib para el tratamiento de la leucemia mieloide crónica en tercera línea: análisis coste-efectividad basado en el enfoque de remisión libre de tratamiento

IntroductionThe first targeted therapy in oncology, imatinib, revolutionized chronic myeloid leukemia (CML) treatment and spurred research in targeted therapies for various cancers. CML results from a chromosomal translocation, forming the BCR-ABL1 fusion gene. Asciminib has been recently approved for 3rd-line refractory or intolerant patients. Treatment-free remission (TFR) is attainable with sustained deep molecular response (DMR) and this approach could be incorporated into pharmacoeconomic models. AimsTo establish a cost-effectiveness model comparing asciminib to approved third-generation tyrosine kinase inhibitors (TKIs) (bosutinib and ponatinib) with a focus on achieving TFR. Additionally, the budgetary impact of incorporating asciminib as a therapeutic alternative is assessed. MethodsThis model is based on a Markov chain with seven states. The condition for achieving TFR is to remain for 5 years in DMR state. Efficacy of the model was measured in QALYs, and the costs included in the base case analysis are based in Spain. A probabilistic (PSA) and deterministic analysis (DSA) were carried out to assess the variability of the model. There were achieved two independent models comparing asciminib vs. bosutinib and asciminib vs. ponatinib. ResultsAsciminib, when compared with ponatinib, is a cost-saving alternative, as efficacy is similar between alternatives, and asciminib has a lower cost of 30,275 €. Asciminib showed 4.33 more QALYs and a higher cost (203,591 €) than bosutinib, resulting in an ICER of €47,010.49 per QALY. PSA shows that the parameters with higher influence in the variability of the model were the probability of transitioning to BP and probabilities of achieving MMR and DMR. A one-way analysis reports that the drug cost has a higher influence on both models, and the discount rate significantly affects the asciminib vs. bosutinib model. ConclusionAsciminib broadens therapeutic choices for patient’s refractory or intolerant to two prior lines of treatment in a cost-effective manner. The costs of drugs significantly impact the overall cost of the disease, emphasizing the importance of the selected discount rates for each drug. Given the relatively low incidence of CML, the introduction of asciminib has a limited budgetary impact, warranting individualized decisions based on patient`s clinical characteristics.

Analysis of the pharmacoeconomic effectiveness of the tyrosine kinase inhibitors therapy in patients with chronic myeloid leukemia in a Single Hematology Center in Plovdiv, Bulgaria

Summary: Chronic myelogenous leukemia (CML) is a pluripotent hemopoietic stem cell malignancy characterized by the presence of a BCR-ABL1 fusion gene derived from a balanced translocation between the long arms of chromosomes 9 and 22 [t(9;22) (q34; q11)] known as the Philadelphia (Ph) chromosome. CML is an acquired hematopoietic stem cell disease common to myelo- and lymphopoiesis, characterized by uncontrolled proliferation of granulopoiesis (Shuvaev et al. 2015; Yordanov and Varbanova 2019). Relevance and goals: Second-generation tyrosine kinase inhibitors (TKIs) (nilotinib, dasatinib, and bosutinib) have an advantage over imatinib (first-generation) in the frequency and speed of achieving cytogenetic and molecular responses in the treatment of chronic myelogenous leukemia (CML), but they cause severe adverse effects and are much more expensive than imatinib, especially if we compare them to the prices of the registered generic products of Imatinib and Dasatinib. “Novartis Tasigna® trial shows superior results to Glivec® in patients with early-stage chronic myeloid leukemia”, reported on 10/20/2021 by Pierre Perrin-Montlouis. In the first direct comparison of these two oral therapies back in 2009 (Тasigna (nilotinib) 2009), as first-line treatment for CML, the results of Tasigna showed statistically significant improvement over Glivec in every measure of efficacy, including major molecular response (MMR), complete cytogenetic response (CCyR) and prevention of progression to accelerated or blast phase, with responses achieved faster in the Tasigna group than in the Glivec group. Furthermore, in the last ten years, CML patients who have achieved a stable deep molecular response for at least 2 years have been included in clinical trials for the management of treatment-free remission (TFR) (Kim et al. 2013; Saußele et al. 2016). On the other hand, the ever-increasing costs of diagnosis, treatment and monitoring of the response of CML to the various therapeutic strategies require conducting pharmacoeconomic analyses of the cost-effectiveness and cost-utility types in order to evaluate which are the cost-effective strategies with a view to introducing them into therapeutic practice. The present study aims to analyze the pharmacoeconomic efficiency of the TKI inhibitors used by the patients with CML-CP in the first and second lines, treated in the hematology clinic at UMHAT “St. George”, MU- Plovdiv during the period 2018–2022. Methods: An economic analysis of the medicinal use of TKIs for a 5-year period (2018–2022) was performed at the national level according to data from the National Health Insurance Fund and the availability, accessibility, and usability of original and generic TKIs in Bulgaria were evaluated. The direct medical costs for the therapy of all patients were calculated, including the costs of the TKI therapy, laboratory tests, and monitoring of the molecular response for the entire treatment period from the appointment of the TKI therapy until the end of 2022. A comparative analysis was conducted to assess the cost-effectiveness of the different therapeutic strategies with TKIs on the first and second lines of treatment of patients with CML-CP in the hematology clinic at UMHAT “St. George” Medical University, Plovdiv, using the decision analysis method and conducting one-way and probalistic sensitivity analyses. Results: The sensitivity analyzes of all pharmacoeconomic models showed the robustness and reliability of the obtained results. The threshold limits of medical costs and the frequency of achieving a deep molecular response determining the choice of first- and second-generation tyrosine kinase inhibitors as first- and second-line therapy for patients with chronic myeloid leukemia in the chronic phase have been determined. Prescribing doctors prefer the original MPs to generic analogues, which is also assumed by the current regulations, according to which even for expensive MPs dispensing by protocols, the prescription is by trade and not by international non-proprietary names (INN), which is why the use of the much cheaper generic MPs is negligibly low compared to original MPs. A personalized approach to the patient’s therapy and monitoring the patient’s molecular response to it, as well as stopping therapy in 25–30% of patients suitable to stop it safely when in TFR phase with a probability of more than 50% of not having a relapse will save additional costs that, by improving the cost-effectiveness of therapy for patients with CML, will be directed towards the treatment of new patients with this or other diseases. Conclusion: These pharmacoeconomic models can be applied to improve diagnostic and therapeutic standards in clinical practice and for the efficient use of the very limited resources for health care in countries like Bulgaria. The conducted cost-effectiveness analyses confirmed that the hematologists at the University Center in Plovdiv adhere to the recommendations of Leukemia Net and the Bulgarian Medical Society of Hematology and achieve not only good therapeutic but also pharmacoeconomic efficiency in the treatment of CML-СР patients in first- and second- line therapy.

Real World Outcomes with Treatment Free Remission in Chronic Myeloid Leukemia-Experience from a Tertiary Care Cancer Centre.

Chronic myeloid leukaemia (CML) is caused by balanced translocation t(9::22)(q34;q11) resulting in formation of pathogenic BCR-ABL fusion gene. Tyrosine kinase inhibitors (TKI) have revolutionised the treatment of CML. Ongoing treatment with TKI leads to side effects and has financial impact. Teratogenic potential of TKI and growth disturbance also represent an important challenge. Thus, TKI discontinuation in form of treatment free remission (TFR) has emerged as a new and important therapeutic goal. In this retrospective study, we reviewed CML patients who were kept on TFR. Inclusion criteria was patient age ≥ 18years diagnosed with CML in chronic phase who met the criteria for TFR and opted for same and who were in DMR but stopped TKI for any reason. We analysed the data for baseline characteristics, molecular relapse (MR), survival without molecular relapse (SWMR), TFR duration and factors affecting MR. We included 38 patients in this analysis. Thirty five (92%) patients were treated with imatinib at diagnosis. Median duration of TKI treatment was 135months. 37 patients (97.5%) achieved DMR on TKI and median time from TKI initiation to DMR was 96months. Median duration of DMR prior to TKI discontinuation was 41months. TKI was discontinued after counselling for TFR in 26 patients (68%) while it was discontinued due to intolerance in 10 patients (29%). At median molecular follow up of 25months, nine patients (23.7%) had molecular relapse. Median SWMR was not reached and 2year estimated SWMR was 65.2% (95%CI,47.2- 83.2). Of all relapses, 5/9 (55.5%) occurred in the first six months of TFR. On univariate analysis, duration of TKI and duration of DMR were predictive of molecular relapse. On multivariate analysis, none of these factors were found to be significant. This retrospective study suggests that for CML CP patients achieving deep molecular response, discontinuing TKI therapy in real-world settings may be feasible while potentially achieving comparable outcomes.

Overall survival in patients with acute lymphoblastic leukemia treated with protocol CALGB 9511 at a tertiary hospital in the state of Ceará.

Introduction: Acute lymphoblastic leukemia (ALL) is the most common neoplasm in childhood and has high survival rates. In adults, due to the biological characteristics of the disease and chemotherapy-related toxicity, survival is lower. CALGB 9511 is a chemotherapy protocol based on pediatric regimens with high remission rates after induction. Objectives: To evaluate the survival of patients with ALL undergoing the CALGB 9511 protocol at Walter Cantídio University Hospital (HUWC); to describe the impact of risk factors: presence of measurable residual disease, BCR-ABL fusion gene status, and allogeneic bone marrow transplant (BMT) on the survival of this group. Methodology: Retrospective evaluation of medical records of patients with ALL treated with this protocol between 2011 and 2022. Statistical analysis was performed using the Kaplan-Meier method to estimate survival probability. Results: 79 patients were eligible; 19% were BCR-ABL positive; the mean 2-year overall survival was 44%; The 2-year survival rate for patients undergoing HSCT was approximately 78%.. Conclusion: The survival curves of the study conducted at HUWC are similar to those described in the literature and corroborate the severity of the disease. Accessibility to new therapeutic modalities is a strategy that can improve the survival of these patients.

Variable characteristics overlooked in human K-562 leukemia cell lines with a common signature

K-562 is a well-known in vitro cellular model that represents human leukemia cell lines. Although the K-562 cells have been extensively characterized, there are inconsistencies in the data across publications, showing the presence of multiple K-562 cell lines. This suggests that analyzing a single K-562 cell line is insufficient to provide reliable reference data. In this study, we compared three K-562 cell lines with different IDs (RCB0027, RCB1635, and RCB1897) to investigate the fundamental characteristics of K-562 cells. Amplifications of the BCR-ABL1 fusion gene and at 13q31 were detected in all three cell lines, whereas each genome exhibited distinctive features of sequence variants and loss of heterozygosity. This implies that each K-562 cell line can be characterized by common and unique features through a comparison of multiple K-562 cell lines. Variations in transcriptome profiles and hemoglobin synthesis were also observed among the three cell lines, indicating that they should be considered sublines that have diverged from the common ancestral K-562 despite no changes from the original cell name. This leads to unintentional differences in genotypes and/or phenotypes among cell lines that share the same name. These data show that characterizing a single K-562 cell line does not necessarily provide data that are applicable to other K-562 cells. In this context, it is essential to modify cell names in accordance with changes in characteristics during cell culture. Furthermore, our data could serve as a reference for evaluating other K-562 sublines, facilitating the discovery of new K-562 sublines with distinct characteristics. This approach results in the accumulation of K-562 sublines with diverged characteristics and expands the options available, which may help in selecting the most suitable K-562 subline for each experiment.

STUDYING THE AGE OF ONSET AND DETECTION OF CHRONIC MYELOID LEUKEMIA USING A THREE-STAGE STOCHASTIC MODEL

Chronic Myeloid Leukemia (CML) is a biphasic malignant clonal disorder that progresses, first with a chronic phase, where the cells have enhanced proliferation only, and then to a blast phase, where the cells have the ability of self-renewal. It is well recognized that the Philadelphia chromosome (which contains the BCR-ABL fusion gene) is the “hallmark of CML”. However, empirical studies have shown that the mere presence of BCR-ABL may not be a sufficient condition for the development of CML, and further modifications related to tumor suppressors may be necessary. Accordingly, we develop a three-mutation stochastic model of CML progression, with the three stages corresponding to the non-malignant cells with BCR-ABL presence, the malignant cells in the chronic phase, and the malignant cells in the blast phase. We demonstrate that the model predictions agree with age incidence data from the United States. Finally, we develop a framework for the retrospective estimation of the time of onset of malignancy, from the time of detection of the cancer.

Oxidative Stress and Chronic Myeloid Leukemia: A Balance between ROS-Mediated Pro- and Anti-Apoptotic Effects of Tyrosine Kinase Inhibitors.

The balanced reciprocal translocation t (9; 22) (q34; q11) and the BCR-ABL fusion gene, which produce p210 bcr-abl protein production with high tyrosine kinase activity, are characteristics of chronic myeloid leukemia, a myeloproliferative neoplasm. This aberrant protein affects several signaling pathways connected to both apoptosis and cell proliferation. It has been demonstrated that tyrosine kinase inhibitor treatment in chronic myeloid leukemia acts by inducing oxidative stress and, depending on its level, can activate signaling pathways responsible for either apoptosis or survival in leukemic cells. Additionally, oxidative stress and reactive oxygen species generation also mediate apoptosis through genomic activation. Furthermore, it was shown that oxidative stress has a role in both BCR-ABL-independent and BCR-ABL-dependent resistance pathways to tyrosine kinases, while patients with chronic myeloid leukemia were found to have a significantly reduced antioxidant level. The ideal environment for tyrosine kinase inhibitor therapy is produced by a favorable oxidative status. We discuss the latest studies that aim to manipulate the redox system to alter the apoptosis of cancerous cells.

Asciminib Maintains Antibody-Dependent Cellular Cytotoxicity against Leukemic Blasts.

B cell acute lymphoblastic leukemia (B-ALL) is characterized by an accumulation of malignant precursor cells. Treatment consists of multiagent chemotherapy followed by allogeneic stem cell transplantation in high-risk patients. In addition, patients bearing the BCR-ABL1 fusion gene receive concomitant tyrosine kinase inhibitor (TKI) therapy. On the other hand, monoclonal antibody therapy is increasingly used in both clinical trials and real-world settings. The introduction of rituximab has improved the outcomes in CD20 positive cases. Other monoclonal antibodies, such as tafasitamab (anti-CD19), obinutuzumab (anti-CD20) and epratuzumab (anti-CD22) have been tested in trials (NCT05366218, NCT04920968, NCT00098839). The efficacy of monoclonal antibodies is based, at least in part, on their ability to induce antibody-dependent cellular cytotoxicity (ADCC). Combination treatments, e.g., chemotherapy and TKI, should therefore be screened for potential interference with ADCC. Here, we report on in vitro data using BCR-ABL1 positive and negative B-ALL cell lines treated with rituximab and TKI. NK cell activation, proliferation, degranulation, cytokine release and tumor cell lysis were analyzed. In contrast to ATP site inhibitors such as dasatinib and ponatinib, the novel first-in-class selective allosteric ABL myristoyl pocket (STAMP) inhibitor asciminib did not significantly impact ADCC in our settings. Our results suggest that asciminib should be considered in clinical trials.

A Case of Rhegmatogenous Retinal Detachment in Chronic Myeloid Leukemia.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by uncontrolled proliferation of granulocytes, caused the BCR-ABL1 fusion gene. While ocular manifestations of CML are rare, the presentations can range from asymptomatic to sudden vision loss. CML associated ocular findings that have been reported include retinal hemorrhages, leukemic infiltrates, and optic disc edema, but a rhegmatogenous retinal detachment (RRD) in the setting of CML has not been described. Case report. A 21-year-old man presented with intermittent vision loss in his right eye, tinnitus in the right ear, and abdominal distension. Work up revealed significant leukocytosis, splenomegaly, and a positive BCR-ABL1 mutation. He was diagnosed with CML and started on systemic therapy. Exam of the right eye revealed a large intraocular mass. After two weeks of systemic treatment, the large elevation in the right eye had improved, allowing visualization of diffuse subretinal whitening. At follow up, an RRD secondary to an atrophic hole in an area of prior subretinal infiltrates were noted. He underwent repair with a scleral buckle. Postoperative course was complicated by redetachment with proliferative vitreoretinopathy, which led to an unrepairable detachment, despite multiple surgeries with silicone oil tamponade. Ocular findings related to CML are rare, with the lowest incidence when compared to other leukemias, and are associated with worse outcomes. Posterior segment findings include intraretinal hemorrhages, Roth spots, and retinal infiltrates. This unique case describes an RRD in CML retinopathy with an aggressive course and poor anatomical result.

Bilateral Sudden Irreversible Hearing Loss in a Case of Chronic Myeloid Leukaemia: A Case Report.

Chronic myeloid leukemia is a type of blood cancer that affects the bone marrow and results in an overproduction of immature WBCs. The genetic mutation that causes CML is the BCR-ABL fusion gene. Adolescents are rarely affected. The case study aims to discuss a rare case of chronic myeloid leukemia causing bilateral hearing impairment, tinnitus, and vertigo. A 30-year-old female presented to the hospital in November, 2021, with sudden hearing impairment and other symptoms, leading to a CML diagnosis. Blood tests revealed hyperleukocytosis with marked neutrophilia, mild basophilia, and eosinophilia, and a BCR-ABL quantitation of 85%. Bone marrow aspiration showed granulocytic hyperplasia, mild left-shifted maturation, and less than 1% blasts. The patient was started with options including tyrosine kinase inhibitors (TKIs) such as Imatinib, which target the BCR-ABL fusion gene, reducing the number of leukemia cells and improving her white blood cell count. However, her deafness persisted, and she became dependent on hearing aids. CML presenting with hearing loss is rare, believed to be related to the infiltration of leukemic cells in the inner ear or microvascular complications. Treatment with tyrosine kinase inhibitors such as Imatinib can improve hematologic parameters, but the effect on hearing loss is uncertaint.

Raman classification of selected subtypes of acute lymphoblastic leukemia (ALL).

B-cell precursor acute lymphoblastic leukemia (BCP-ALL) with chromosome translocations like KMT2A gene rearrangement (KMT2A-r) and BCR-ABL1 fusion gene have been recognized as crucial drivers in both BCP-ALL leukemogenesis and treatment management. Standard diagnostic protocols for proliferative diseases of the hematopoietic system, like KMT2A-r-ALL, are genetically based and strongly molecularly oriented. Therefore, an efficient diagnostic procedure requires not only experienced and multidisciplinary laboratory staff but also considerable instrumentation and material costs. In recent years, a Raman spectroscopy method has been increasingly used to detect subtle chemical changes in individual cells resulting from stress or disease. Therefore, the objective of this study was to identify Raman signatures for the molecular subtypes and to develop a classification method based on the unique spectroscopic profile of in vitro models that represent specific aberrations aimed at KMT2A-r (RS4;11, and SEM) and the BCR-ABL1 fusion gene (SUP-B15, BV-173, and SD-1). Data analysis was based on chemometric methods, i.e. principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and support vector machine (SVM). The PCA-based multivariate model was used for pattern recognition of each investigated group of cells while PLS-DA and SVM were used to build models for the discrimination of spectra from the studied BCP-ALL molecular subtypes. The results showed that the studied molecular subtypes of ALL have characteristic spectroscopic profiles reflecting their peculiar biochemical state. The content of lipids (1600 cm-1), nucleic acids (789 cm-1), and haemoproteins (754, 1130, and 1315 cm-1), which are crucial in cell metabolism, was indicated as the main source of differentiation between subtypes. Identification of spectroscopic markers of cells with BCR-ABL1 or KMT2A-r may be useful in pharmacological studies to monitor the effectiveness of chemotherapy and further to understand differences in molecular responses between leukemia primary cells and cell lines.

Mechanisms underlying therapeutic resistance of tyrosine kinase inhibitors in chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is a malignant clonal disease involving hematopoietic stem cells that is characterized by myeloid cell proliferation in bone marrow and peripheral blood, and the presence of the Philadelphia (Ph) chromosome with BCR-ABL fusion gene. Treatment of CML has dramatically improved since the advent of tyrosine kinase inhibitors (TKI). However, there are a small subset of CML patients who develop resistance to TKI. Mutations in the ABL kinase domain (KD) are currently recognized as the leading cause of TKI resistance in CML. In this review, we discuss the concept of resistance and summarize recent advances exploring the mechanisms underlying CML resistance. Overcoming TKI resistance appears to be the most successful approach to reduce the burden of leukemia and enhance cures for CML. Advances in new strategies to combat drug resistance may rapidly change the management of TKI-resistant CML and expand the prospects for available therapies.

Clinical Characteristics and Diagnosis of Ph-Positive Mixed Phenotype Acute Leukemia.

The goal was to improve the clinical cognition of Ph-positive mixed phenotype acute leukemia and avoid misdiagnosis or delayed diagnosis. The clinical manifestations and laboratory results (bone marrow cell morphology, multiparameter flow cytometry, and cytogenetics) of a case of Ph-positive mixed phenotype acute leukemia were analyzed, and related literature was reviewed. Blood routine: WBC 386.35 x 109/L, HGB 117.00 g/L, PLT 31 x 109/L; 80% of the original cells can be seen by artificial classification. Morphological examination of bone marrow cells showed that the proliferation of nucleated cells was obviously active, and the original cells accounted for 76%. The size of the original cells was somewhat uniform, most of the cells had less mass, were stained light grayish blue, the cytoplasm particles were not obvious, the nuclei were mostly round or quasi-round, some of them showed distortion and nuclear notch, and the chromatin was coarse. Some of the cells were rich in mass, small azurin granules were seen, the nuclei were regular, most of them were round, the chromatin was fine, the myeloperoxidase and esterase staining were negative, the eosinophils accounted for 2.5%, and the basophils accounted for 0.5%. Flow cytometry immunotyping: Two groups of abnormal cells were seen in the bone marrow. 1. A group included 12.32% of nuclear cells and showed abnormal myeloid primitive cell phenotype. Main expression: CD117, CD34, CD38, HLA-DR, CD33, CD64, CD123, weak expression: CD13, CD19. 2. The other group included 45.61% of the nuclear cells and had a B-lymphoblastic phenotype. Main expression: CD34, CD38, HLA-DR, CD123, CD19, CD10, CD9, cCD79a, TDT, weak expression of CD13, CD22. Mixed phenotype acute leukemia (M/B) immunophenotype was considered. Chromosome: 46,XY,t(9; 22)(q34;q11.2) [20]. BCR-ABL (P210) fusion gene was positive. Mixed phenotype acute leukemia (MPAL) is a rare type of malignant hematologic disease. Its diagnosis is based on the comprehensive evaluation of bone marrow cell morphology, immunophenotype, molecular and cytogenetic features.

Treatment outcome of the tyrosine kinase inhibitor (bosutinib) in previously treated chronic myeloid leukemia patients (sample of Iraqi patients)

Abstract: BACKGROUND: Chronic myeloid leukemia (CML) is a type of myeloproliferative neoplasm characterized by the excessive accumulation of malignant myeloid cells in the bone marrow and peripheral blood. This condition is primarily triggered by a specific chromosomal translocation known as t(9;22) (q34.13;q11.23), which leads to the formation of the BCR-ABL fusion gene. The treatment landscape for CML has undergone significant changes with the approval of tyrosine kinase inhibitors (TKIs) targeting the BCR-ABL1 kinase activity. One such inhibitor is bosutinib, which has been available for several years to treat patients with chronic, accelerated, and blast-phase CML who have shown resistance or intolerance to previous therapies. OBJECTIVES: The aim of this study was to assess efficacy and safety of Bosutinib as a 2nd line therapy in CML patients, in addition to effect of adherence to treatment on patients response. PATIENTS AND METHODS: Eighty-five patients with CML were enrolled in a prospective cohort study from October 2021 to October 2022 at Hematology Center in Medical City Complex – Baghdad. All patients failed to at least one TKI, and all of them started escalated dose of bosutinib. The patients were followed-up by assessing molecular and cytogenetic response at 3 and 6 months and monitored carefully for adverse events (AEs) which were graded by common terminology IX criteria for AEs version 5. Adherence to bosutinib was also monitored by a specific adherence scale to optimize the response rate to treatment. RESULTS: The mean age of patients was 47.3 ± 14.9 (range: 18–77), with male:female ratio 1.4:1. Status of CML patients showed that 89.4% were in the chronic phase, 5.8% in accelerated phase, and 4.7% in blast phase. Regarding the number of previous TKIs before bosutinib, 72.9% of patients failed to prior one TKI (imatinib). At 6 months (72.3%), patients achieve optimal response according to European Leukemia Net criteria 2013. Gastrointestinal symptoms and dermatological manifestations were the most common nonhematological AEs of bosutinib. According to 9-item Morisky Medication Adherence Scale, 42% of patients were adherent to medication which showed a significant association with a higher number of optimal response (P = 0.0001). CONCLUSION: Bosutinib is effective with a high and promising response as a subsequent line treatment in CML patients, and it is generally safe and associated with mild-to-moderate tolerable and manageable AEs. Adherence to the drug plays a significant role in optimal response to bosutinib.

Successful Therapeutic Leukapheresis in a Patient of Lobar Pneumonia with Hyperleukocytosis: A Case Report

ABSTRACT Hyperleukocytosis is a rare and potentially life-threatening condition that can cause leukostasis and organ dysfunction. This case report describes the case of a 69-year-old female who presented with fever, drowsiness, and consolidation in the left lung lower lobe. Initial investigations showed an increased total leukocyte count (TLC) of 89 × 103/μL, which further increased to 111.9 × 103/μL despite treating with intravenous antibiotics. A bone marrow biopsy revealed myeloid hyperplasia, but the BCR-ABL fusion gene test was negative. Due to symptomatic leukostasis and rapid deterioration of the patient’s condition, therapeutic leukapheresis (TL) was performed. During the first sitting, the device parameters were optimized for maximum platelets and the leukocytes removal. The second sitting of TL was carried out on the next day and the TLC was further reduced to 22.3 × 103/μL. The patient’s general condition and mental status improved significantly and she was taken off the mechanical ventilation and discharged after 7 days with a TLC count of 14.59 × 103/μL. She was regularly followed up for the next 3 months and the counts have remained within normal limits. The case reports highlight that TL may be helpful in similar clinical conditions with symptomatic leukostasis.