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1.
Urol Oncol ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39069444

RESUMEN

BACKGROUND: To test for differences in organ-confined pathological tumor stage (pT) and intermediate International Society of Urological Pathologists (ISUP) grade vs. nonorgan confined pT stage and high ISUP grade and biochemical recurrence (BCR) after radical prostatectomy (RP). METHODS: Relying on a tertiary-care database, prostate cancer patients undergoing RP between January 2014 and December 2021 were stratified according to their combination of pT stage and ISUP grade in RP specimens (pT2 ISUP4/5 vs. pT3/4 ISUP2 vs. pT3/4 ISUP3). As Active Surveillance is recommended in ISUP1, these patients were excluded. Moreover, patients with pT2 ISUP2/3 are known for their good prognosis and pT3/4 ISUP4/5 patients for their poor prognosis. Therefore, these patients were also excluded from analyses. Kaplan-Meier survival analyses and multivariable Cox regression models addressed BCR after RP. RESULTS: Of 215 RP patients, 29 (13%) exhibited pT2 ISUP4/5 vs. 122 (57%) pT3/4 ISUP2 vs. 64 (30%) pT3/4 ISUP3 pathology. In survival analyses, 3-year BCR-free survival rates were 95% in pT2 ISUP4/5 vs. 88% in pT3/4 ISUP2 vs. 65% in pT3/4 ISUP3 patients (P < 0.001). In multivariable Cox regression models addressing BCR, pT3/4 ISUP3 pathology was associated with higher BCR rate relative to pT2 ISUP4/5 pathology (hazard ratio 3.42, 95% confidence interval 1.07-10.94; P = 0.039), but not pT3/4 ISUP2 pathology (P = 0.6). CONCLUSION: Compared to prostate cancer patients with pT2 ISUP4/5 pathology, the combination of pT3/4 ISUP3 pathology is associated with higher risk of BCR after RP. In consequence, patients with pT3/4 ISUP3 pathology should be considered for a closer postoperative follow-up.

2.
Glob Pediatr Health ; 11: 2333794X241256863, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39070153

RESUMEN

Objectives. This study aimed to find the association between clinical characteristics, cytogenetics, and post-induction outcomes of childhood acute lymphoblastic leukemia. Methods. The study was conducted at the Indus Hospital in Karachi. Initial total leukocyte count (TLC), cytogenetics, CNS status, and post-induction remission status were recorded. Results. Out of 108 children diagnosed with ALL, 66 (61.1%) were male and 42 (38.9%) were female. The majority 90 (83.3%) had B-ALL. CNS1 status was observed in 76 (84.4%) B-ALL and 18 (88.9%) T-ALL. All T-ALL and 89 (98.8%) B-ALL achieved remission post-induction. In B-ALL, 50 (55.5%) had a normal diploid karyotype, and 22 (24.4%) had numerical abnormalities. No typical gene rearrangement was observed in 66 (73.3%), 11 (12.2%) had BCR::ABL1, 10 (11.1%) had ETV6::RUNX1 and 3 (3.3%) KMT2A on FISH. No significant difference was observed between cytogenetics and clinical characteristics (P > .05). Conclusion. The study provides valuable data on childhood acute lymphoblastic leukemia in the Pakistani population.

3.
Int J Mol Sci ; 25(14)2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39063200

RESUMEN

While BCR::ABL1 tyrosine kinase inhibitors have transformed the treatment paradigm for chronic myeloid leukemia (CML), disease progression and treatment resistance due to BCR::ABL1-dependent and BCR::ABL1-independent mechanisms remain a therapeutic challenge. Natural compounds derived from plants have significantly contributed to cancer pharmacotherapy. This study investigated the efficacy of an active component of Leea indica, a local medicinal plant, in CML. Using high-performance liquid chromatography-electrospray ionization-mass spectrometry, a chemical constituent from L. indica extract was isolated and identified as gallic acid. Commercially obtained gallic acid was used as a chemical standard. Gallic acid from L. indica inhibited proliferation and induced apoptosis in CML cell lines, as did the chemical standard. Furthermore, gallic acid induced apoptosis and decreased the colony formation of primary CML CD34+ cells. The combination of isolated gallic acid or its chemical standard with BCR::ABL1 tyrosine kinase inhibitors resulted in a significantly greater inhibition of colony formation and cell growth compared to a single drug alone. Mechanistically, CML cells treated with gallic acid exhibited the disruption of multiple oncogenic pathways including ERK/MAPK, FLT3 and JAK/STAT, as well as impaired mitochondrial respiration. Rescue studies showed that gallic acid is significantly less effective in inducing apoptosis in mitochondrial respiration-deficient ρ0 cells compared to wildtype cells, suggesting that the action of gallic acid is largely through the inhibition of mitochondrial respiration. Our findings highlight the therapeutic potential of L. indica in CML and suggest that gallic acid may be a promising lead chemical constituent for further development for CML treatment.


Asunto(s)
Apoptosis , Proliferación Celular , Proteínas de Fusión bcr-abl , Ácido Gálico , Leucemia Mielógena Crónica BCR-ABL Positiva , Mitocondrias , Inhibidores de Proteínas Quinasas , Transducción de Señal , Ácido Gálico/farmacología , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Proteínas de Fusión bcr-abl/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Transducción de Señal/efectos de los fármacos , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral
4.
Elife ; 122024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39056282

RESUMEN

The evolutionary conservation of non-core RAG regions suggests significant roles that might involve quantitative or qualitative alterations in RAG activity. Off-target V(D)J recombination contributes to lymphomagenesis and is exacerbated by RAG2' C-terminus absence in Tp53-/- mice thymic lymphomas. However, the genomic stability effects of non-core regions from both Rag1c/c and Rag2c/c in BCR-ABL1+ B-lymphoblastic leukemia (BCR-ABL1+ B-ALL), the characteristics, and mechanisms of non-core regions in suppressing off-target V(D)J recombination remain unclear. Here, we established three mouse models of BCR-ABL1+ B-ALL in mice expressing full-length RAG (Ragf/f), core RAG1 (Rag1c/c), and core RAG2 (Rag2c/c). The Ragc/c (Rag1c/c and Rag2c/c) leukemia cells exhibited greater malignant tumor characteristics compared to Ragf/f cells. Additionally, Ragc/c cells showed higher frequency of off-target V(D)J recombination and oncogenic mutations than Ragf/f. We also revealed decreased RAG cleavage accuracy in Ragc/c cells and a smaller recombinant size in Rag1c/c cells, which could potentially exacerbate off-target V(D)J recombination in Ragc/c cells. In conclusion, these findings indicate that the non-core RAG regions, particularly the non-core region of RAG1, play a significant role in preserving V(D)J recombination precision and genomic stability in BCR-ABL1+ B-ALL.


Asunto(s)
Proteínas de Unión al ADN , Proteínas de Fusión bcr-abl , Proteínas de Homeodominio , Recombinación V(D)J , Animales , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Recombinación V(D)J/genética , Proteínas de Fusión bcr-abl/genética , Proteínas de Fusión bcr-abl/metabolismo , Ratones , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Carcinogénesis/genética , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo
5.
Medicina (Kaunas) ; 60(7)2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39064548

RESUMEN

Background: Biochemical recurrence (BCR) represents the rise of prostate-specific antigen (PSA) levels after treatment with curative radical prostatectomy (RP) or radiation for prostate cancer. The objective of the current study was to test for the association between patient characteristics, namely age, body mass index (BMI), as well as prostate volume at surgery, and BCR after RP. Material and Methods: Within a tertiary care database, patients with prostate cancer treated with RP between January 2014 and June 2023 were included. Kaplan-Meier survival analyses and Cox regression models addressed BCR after RP according to patient characteristics. Results: Of 821 patients, the median age was 66 years (interquartile range [IQR] 61-71 years), BMI was 26.2 kg/m2 (IQR 24.3-28.8 kg/m2), and prostate volume was 40 cm3 (IQR 30-55 cm3). Median follow-up was 20 months. In survival analyses, the three-year BCR-free survival rates were 81 vs. 84 vs. 81% in patients aged ≤60 vs. 61-69 vs. 70 years (p = 0.1). In patients with BMI < 25.0 vs. 25.0-29.9 vs. ≥30.0 kg/m2, the three-year BCR-free survival rates were 84 vs. 81 vs. 84% (p = 0.7). In patients with prostate volume ≤40 vs. >40 cm3, the three-year BCR-free survival rates were 85 vs. 80% (p = 0.004). In multivariable Cox regression models accounting for patient and pathologic tumor characteristics and adjuvant radiation therapy, a higher prostate volume independently predicted BCR as continuous (hazard ratio 1.012, 95% confidence interval 1.005-1.019; p < 0.001), as well as categorized the variable based on the median (hazard ratio 1.66, 95% confidence interval 1.17-2.36; p = 0.005). Conversely, neither age nor BMI were significantly associated with BCR after RP. Conclusions: The higher prostate volume independently predicted BCR after RP, but not age or BMI at surgery. Consequently, patients with an elevated prostate volume should be considered for closer postoperative follow-up.


Asunto(s)
Índice de Masa Corporal , Recurrencia Local de Neoplasia , Antígeno Prostático Específico , Prostatectomía , Neoplasias de la Próstata , Humanos , Masculino , Prostatectomía/métodos , Persona de Mediana Edad , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/sangre , Anciano , Antígeno Prostático Específico/sangre , Recurrencia Local de Neoplasia/sangre , Estimación de Kaplan-Meier , Modelos de Riesgos Proporcionales , Estudios Retrospectivos
6.
Biochimie ; 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39009062

RESUMEN

Chronic lymphocytic leukaemia (CLL) is a heterogenous disease characterized by the accumulation of neoplastic CD5+/CD19+ B lymphocytes. The spreading of the leukaemia relies on the CLL cell's ability to survive in the blood and migrate to and proliferate within the bone marrow and lymphoid tissues. Some patients with CLL are either refractory to the currently available therapies or relapse after treatment; this emphasizes the need for novel therapeutic strategies that improving clinical responses and overcome drug resistance. CD38 is a marker of a poor prognosis and governs a set of survival, proliferation and migration signals that contribute to the pathophysiology of CLL. The literature data evidence a spatiotemporal association between the cell surface expression of CD38 and that of other CLL antigens, such as the B-cell receptor (BCR), CD19, CD26, CD44, the integrin very late antigen 4 (VLA4), the chemokine receptor CXCR4, the vascular endothelial growth factor receptor-2 (VEGF-R2), and the neutrophil gelatinase-associated lipocalin receptor (NGAL-R). Most of these proteins contribute to CLL cell survival, proliferation and trafficking, and cooperate with CD38 in multilayered signal transduction processes. In general, these antigens have already been validated as therapeutic targets in cancer, and a broad repertoire of specific monoclonal antibodies and derivatives are available. Here, we review the state of the art in this field and examine the therapeutic opportunities for cotargeting CD38 and its partners in CLL, e.g. by designing novel bi-/trispecific antibodies.

7.
Biochemistry (Mosc) ; 89(6): 1094-1108, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38981703

RESUMEN

Despite significant progress made over the past two decades in the treatment of chronic myeloid leukemia (CML), there is still an unmet need for effective and safe agents to treat patients with resistance and intolerance to the drugs used in clinic. In this work, we designed 2-arylaminopyrimidine amides of isoxazole-3-carboxylic acid, assessed in silico their inhibitory potential against Bcr-Abl tyrosine kinase, and determined their antitumor activity in K562 (CML), HL-60 (acute promyelocytic leukemia), and HeLa (cervical cancer) cells. Based on the analysis of computational and experimental data, three compounds with the antitumor activity against K562 and HL-60 cells were identified. The lead compound efficiently suppressed the growth of these cells, as evidenced by the low IC50 values of 2.8 ± 0.8 µM (K562) and 3.5 ± 0.2 µM (HL-60). The obtained compounds represent promising basic structures for the design of novel, effective, and safe anticancer drugs able to inhibit the catalytic activity of Bcr-Abl kinase by blocking the ATP-binding site of the enzyme.


Asunto(s)
Antineoplásicos , Diseño de Fármacos , Proteínas de Fusión bcr-abl , Inhibidores de Proteínas Quinasas , Humanos , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Proteínas de Fusión bcr-abl/metabolismo , Células K562 , Células HeLa , Pirimidinas/farmacología , Pirimidinas/química , Simulación del Acoplamiento Molecular , Células HL-60 , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular/efectos de los fármacos , Simulación por Computador
8.
Arch Esp Urol ; 77(5): 491-497, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38982777

RESUMEN

BACKGROUND: Existing models for predicting that biochemical recurrence (BCR) will occur in patients after radical prostatectomy (RP) vary in their predictive results from magnetic resonance imaging (MRI). This study aimed to assess the predictive value of preoperative prostate-specific antigen (PSA) levels combined with MRI features in determining BCR following radical prostatectomy. METHODS: A retrospective analysis was conducted on a cohort comprising 102 patients who underwent radical prostatectomy at our hospital between January 2019 and December 2019. On the basis of the outcomes observed during a 4-year follow-up after surgery, the patients were categorised into BCR group (n = 52) and non-BCR group (n = 50). Differences in preoperative PSA levels and MRI characteristics between the two groups were compared, and factors influencing postoperative BCR were analysed. The receiver operating characteristic curve was drawn, and the sensitivity, specificity, area under the curve (AUC) and Youden index were calculated to observe the predictive value of the combination of preoperative PSA level and MRI features for BCR following radical prostatectomy. RESULTS: Logistic regression analysis showed that preoperative PSA level, postoperative Gleason score, data system (Prostate Imaging-Reporting and Data System (PI-RADS)) score and clinical T stage were independent risk factors for BCR in patients following radical prostatectomy, with odds ratio (OR) greater than 1. The AUC value of preoperative PSA level combined with PI-RADS score was 0.921, surpassing the AUC values of 0.783, 0.822, 0.617 and 0.608 predicted by preoperative PSA level, postoperative Gleason score, PI-RADS score and clinical T stage alone, respectively. CONCLUSIONS: Postoperative BCR in patients with prostate cancer undergoing radical prostatectomy is associated with preoperative PSA level, postoperative Gleason score, PI-RADS score and clinical T stage. The combination of preoperative PSA level and MRI features can improve the predictive efficiency for postoperative BCR.


Asunto(s)
Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia , Valor Predictivo de las Pruebas , Antígeno Prostático Específico , Prostatectomía , Neoplasias de la Próstata , Humanos , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/sangre , Periodo Preoperatorio
10.
Methods Mol Biol ; 2826: 15-30, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39017882

RESUMEN

Ultrasound-guided fine needle biopsy, also known as fine needle aspiration, of human axillary lymph nodes is a safe and effective procedure to assess the immune response within the lymph nodes following vaccination. Once acquired, lymph node cells can be characterized via flow cytometric immunophenotyping and/or single-cell RNA sequencing for gene expression and T and B cell receptors. Analysis of the immune cells from the lymph nodes enables the investigation of T and B cells that may interact at this site. These interactions may lead to germinal center formation and expansion, critical for the generation of effective immunity to vaccination. Directly studying the dynamic processes and interaction of the key cells has been challenging in humans due to the anatomically protected location of these cells. Here, we describe the methods involved in ultrasound-guided fine needle biopsy of human axillary lymph nodes in response to vaccination and subsequent analyses of the B cell populations.


Asunto(s)
Axila , Linfocitos B , Ganglios Linfáticos , Vacunación , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/inmunología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Vacunación/métodos , Citometría de Flujo/métodos , Inmunofenotipificación , Biopsia con Aguja Fina/métodos , Biopsia Guiada por Imagen/métodos
11.
Mol Cell Biochem ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009935

RESUMEN

BCR::ABL1 inhibitors, the treatment of choice for the majority of patients with chronic myeloid leukaemia (CML), can cause vascular side effects that vary between agents. The exact underlying mechanisms are still poorly understood, but the vascular endothelium has been proposed as a site of origin. The present study investigates the effects of three BCR::ABL1 inhibitors, ponatinib, nilotinib and imatinib, on angiogenesis and signalling in human endothelial cells in response to vascular endothelial growth factor (VEGF). The experiments were performed in endothelial cells isolated from human umbilical veins. After exposure to imatinib, ponatinib and nilotinib, the angiogenic capacity of endothelial cells was assessed in spheroid assays. VEGF-induced signalling pathways were examined in Western blotting experiments using different specific antibodies. RNAi technology was used to downregulate proteins of interest. Intracellular cGMP levels were measured by ELISA. Imatinib had no effect on endothelial function. Ponatinib inhibited VEGF-induced sprouting, while nilotinib increased spontaneous and VEGF-stimulated angiogenesis. These effects did not involve wild-type ABL1 or ABL2, as siRNA-mediated knockdown of these kinases did not affect angiogenesis and VEGF signalling. Consistent with their effects on sprouting, ponatinib and nilotinib affected angiogenic pathways in opposite directions. While ponatinib inhibited VEGF-induced signalling and cGMP formation, nilotinib activated angiogenic signalling, in particular phosphorylation of extracellular signal-regulated kinase 1/2 (Erk1/2). The latter occurred in an epidermal growth factor receptor (EGFR)-dependent manner possibly via suppressing Fyn-related kinase (FRK), a negative regulator of EGFR signalling. Both, pharmacological inhibition of Erk1/2 or EGFR suppressed nilotinib-induced angiogenic sprouting. These results support the notion that the vascular endothelium is a site of action of BCR::ABL1 inhibitors from which side effects may arise, and that the different vascular toxicity profiles of BCR::ABL1 inhibitors may be due to their different actions at the molecular level. In addition, the as yet unknown pro-angiogenic effect of nilotinib should be considered in the treatment of patients with comorbidities associated with pathological angiogenesis, such as ocular disease, arthritis or obesity.

12.
Methods Mol Biol ; 2826: 31-44, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39017883

RESUMEN

Next-generation sequencing has the potential to uncover the complex nature of B cell immunity by revealing the full complexity of B cell receptor (BCR) repertoires in health and disease. However, there are drawbacks which can compromise the validity of the repertoire analysis caused by quantitative bias and accumulation of sequencing errors during the library preparation and sequencing. Here, we provide an optimized protocol designed to minimize bias for reproducible and accurate preparation of human BCR repertoire libraries for high-throughput sequencing.


Asunto(s)
Linfocitos B , Secuenciación de Nucleótidos de Alto Rendimiento , Receptores de Antígenos de Linfocitos B , Humanos , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/inmunología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Linfocitos B/inmunología , Linfocitos B/metabolismo , Biblioteca de Genes
13.
Mucosal Immunol ; 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39038753

RESUMEN

Human adenovirus (HAdV) pneumonia poses a major health burden for young children, however, factors that contribute to disease severity remain elusive. We analyzed immune cells from bronchoalveolar lavage (BAL) of children with HAdV pneumonia and found that CD19+CD21low B cells were significantly enriched in the BAL and were associated with increased autoantibody concentrations and disease severity. Myeloid cells, PD-1+CD4+ T helper cells and CD21low B cells formed tertiary lymphoid structures within the respiratory tracts. Myeloid cells promoted autoantibody production by expressing high amounts of B cell activating factor (BAFF). In contrast, PD-1+CD4+ T helper cells induced production of IgG1 and IgG3 antibodies but suppressed autoreactive IgGs by initiating B cell receptor editing. In summary, this study reveals cellular components involved in protective versus autoreactive immune pathways in the respiratory tract, and these findings provide potential therapeutic targets for severe HAdV lower respiratory tract infections.

14.
Leuk Res Rep ; 21: 100403, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39035746

RESUMEN

Background: Chronic Myeloid Leukemia is characterized by the presence of the Philadelphia Chromosome (Ph) which contains the BCR::ABL1 fusion gene that occurs due to a reciprocal translocation between chromosomes 9 and 22. This accounts for up to 15 % of all adult leukemias [1]. Most patients treated with first line tyrosine kinase inhibitor (TKI) imatinib achieve durable response but may undergo relapse at some stage [2]. The most important mechanism that may confer imatinib resistance is point mutation within BCR::ABL kinase domain. Other generation ABL tyrosine kinase inhibitors such as dasatinib, nilotinib, bosutinib and ponatinib help to overcome imatinib resistance [3]. Sensitivity of the patient to each of the above TKIs depends upon the individual candidate mutation present. Thus, it is important to perform mutation analysis for effective therapeutic management of CML patients once they show imatinib resistance. We used direct sequencing to identify the different types of mutations responsible for resistance of imatinib treatment from north India. Methods: In this study, the patient resistance for the imatinib were analyzed for BCR::ABL kinase domain mutation by direct sequencing and the detected mutations along with their percentage prevalence were reported. Results: 329 patients with CML-CP were analyzed for BCR::ABL kinase domain mutation. Total 66 (20.06 %) patients out of 329 had mutation in at least one of the domains of BCR::ABL conferring resistance to different generations of TKI. Mutations in BCR::ABL kinase domain was observed in different domain of BCR::ABL. ATP binding P-Loop (42.42 %), Direct binding site (36.36 %), C-Loop (10.60 %), A-Loop (6.06 %), SH2 contact (3.03 %), SH3 contact (1.51 %). Conclusion: Total 20.06 % patients (66/329) show mutation in at least one of the structural motifs of BCR-ABL kinase domain, which further confer the resistance to a particular generation of TKI.

15.
Mol Cancer ; 23(1): 138, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970095

RESUMEN

BACKGROUND: The BCR::ABL1 is a hallmark of chronic myeloid leukemia (CML) and is also found in acute lymphoblastic leukemia (ALL). Most genomic breaks on the BCR side occur in two regions - Major and minor - leading to p210 and p190 fusion proteins, respectively. METHODS: By multiplex long-distance PCR or next-generation sequencing technology we characterized the BCR::ABL1 genomic fusion in 971 patients (adults and children, with CML and ALL: pediatric ALL: n = 353; pediatric CML: n = 197; adult ALL: n = 166; adult CML: n = 255 patients) and designed "Break-App" web tool to allow visualization and various analyses of the breakpoints. Pearson's Chi-Squared test, Kolmogorov-Smirnov test and logistic regression were used for statistical analyses. RESULTS: Detailed analysis showed a non-random distribution of breaks in both BCR regions, whereas ABL1 breaks were distributed more evenly. However, we found a significant difference in the distribution of breaks between CML and ALL. We found no association of breakpoints with any type of interspersed repeats or DNA motifs. With a few exceptions, the primary structure of the fusions suggests non-homologous end joining being responsible for the BCR and ABL1 gene fusions. Analysis of reciprocal ABL1::BCR fusions in 453 patients showed mostly balanced translocations without major deletions or duplications. CONCLUSIONS: Taken together, our data suggest that physical colocalization and chromatin accessibility, which change with the developmental stage of the cell (hence the difference between ALL and CML), are more critical factors influencing breakpoint localization than presence of specific DNA motifs.


Asunto(s)
Puntos de Rotura del Cromosoma , Proteínas de Fusión bcr-abl , Leucemia Mielógena Crónica BCR-ABL Positiva , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Proteínas de Fusión bcr-abl/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Adulto , Niño , Masculino , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento
16.
Proc Natl Acad Sci U S A ; 121(31): e2404728121, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39042672

RESUMEN

How different classes of the B cell antigen receptor (BCR) sense viral antigens used in vaccination protocols is poorly understood. Here, we study antigen binding and sensing of human Ramos B cells expressing a BCR of either the IgM or IgG1 class with specificity for the CD4-binding-site of the envelope (Env) protein of the HIV-1. Both BCRs carry an identical antigen binding site derived from the broad neutralizing antibody (bnAb) CH31. We find a five times higher expression of the IgG1-BCR in comparison to the IgM-BCR on the surface of transfected Ramos B cells. The two BCR classes also differ from each other in their interaction with cognate HIV Env antigens in that the IgG1-BCR and IgM-BCR bind preferentially to polyvalent and monovalent antigens, respectively. By generating an IgM/IgG1 chimeric BCR, we found that the class-specific BCR expression and antigen-sensing behavior can be transferred with the CH1γ domain from the IgG1-BCR to the IgM-BCR. Thus, the class of CH1 domain has an impact on BCR assembly and expression as well as on antigen sensing.


Asunto(s)
VIH-1 , Inmunoglobulina G , Inmunoglobulina M , Receptores de Antígenos de Linfocitos B , Humanos , Inmunoglobulina M/inmunología , Inmunoglobulina G/inmunología , Receptores de Antígenos de Linfocitos B/metabolismo , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/inmunología , VIH-1/inmunología , VIH-1/genética , Linfocitos B/inmunología , Linfocitos B/metabolismo , Anticuerpos Anti-VIH/inmunología , Dominios Proteicos , Anticuerpos Neutralizantes/inmunología
17.
Eur J Haematol ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38994654

RESUMEN

Precise and reliable predictive parameters to accurately identify chronic myeloid leukemia (CML) patients who can successfully discontinue their tyrosine kinase inhibitor (TKI) treatment are lacking. One promising parameter is depth of molecular response measured by BCR::ABL1 digital PCR (dPCR). The aim of this study was to validate a previously described prediction cutoff of 0.0023%IS and to assess the value of dPCR for treatment-free remission (TFR) prediction in relation to other clinical parameters. A droplet-based dPCR assay assessed BCR::ABL1 %IS prior to TKI discontinuation. The primary endpoint was molecular recurrence (MolR) by 36 months. A total of 186 patients from Canada, Germany, and the Netherlands were included. In patients with a first TKI discontinuation attempt (n = 163), a BCR::ABL1 dPCR < and ≥0.0023%IS had a MolR probability of 33% and 70%, respectively. Patients treated less than 6 years with a BCR::ABL1 dPCR <0.0023%IS had a MolR probability of 31%. After correction for treatment duration, both high dPCR value and the use of imatinib (vs. second-generation TKI) were significantly associated with a higher risk of MolR (HR of 3.66, 95%CI 2.06-6.51, p < .001; and 2.85, 95%CI 1.25-6.46, p = .013, respectively). BCR::ABL1 dPCR was not associated with TFR outcome after second TKI discontinuation, however, with the limitation of a small number of patients analyzed (n = 23). In conclusion, BCR::ABL1 digital PCR based on the cutoff of 0.0023%IS is a valuable predictive tool to identify CML patients with a high probability of TFR success after first TKI discontinuation, including patients treated for less than 6 years.

18.
Pharmacol Res Perspect ; 12(4): e1214, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39031848

RESUMEN

In the treatment of chronic myeloid leukemia (CML), resistance to BCR-ABL inhibitors makes it difficult to continue treatment and is directly related to life expectancy. Therefore, asciminib was introduced to the market as a useful drug for overcoming drug resistance. While combining molecular targeted drugs is useful to avoid drug resistance, the new BCR-ABL inhibitor asciminib and conventional BCR-ABL inhibitors should be used as monotherapy in principle. Therefore, we investigated the synergistic effect and mechanism of the combination of asciminib and imatinib. We generated imatinib-resistant cells using the human CML cell line K562, examined the effects of imatinib and asciminib exposure on cell survival using the WST-8 assay, and comprehensively analyzed genetic variation related to drug resistance using RNA-seq and real-time PCR. A synergistic effect was observed when imatinib and asciminib were combined with or without imatinib resistance. Three genes, GRRP1, ESPN, and NOXA1, were extracted as the sites of action of asciminib. Asciminib in combination with BCR-ABL inhibitors may improve the therapeutic efficacy of conventional BCR-ABL inhibitors and prevent the development of resistance. Its dosage may be effective even at minimal doses that do not cause side effects. Further verification of this mechanism of action is needed. Additionally, cross-resistance between BCR-ABL inhibitors and asciminib may occur, which needs to be clarified through further validation as soon as possible.


Asunto(s)
Resistencia a Antineoplásicos , Sinergismo Farmacológico , Proteínas de Fusión bcr-abl , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva , Mesilato de Imatinib/farmacología , Humanos , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Proteínas de Fusión bcr-abl/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Inhibidores de Proteínas Quinasas/farmacología , Supervivencia Celular/efectos de los fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Antineoplásicos/farmacología , Niacinamida/análogos & derivados , Pirazoles
19.
Front Immunol ; 15: 1383753, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39040106

RESUMEN

Outbreaks of Ebolaviruses, such as Sudanvirus (SUDV) in Uganda in 2022, demonstrate that species other than the Zaire ebolavirus (EBOV), which is currently the sole virus represented in current licensed vaccines, remain a major threat to global health. There is a pressing need to develop effective pan-species vaccines and novel monoclonal antibody-based therapeutics for Ebolavirus disease. In response to recent outbreaks, the two dose, heterologous Ad26.ZEBOV/MVA-BN-Filo vaccine regimen was developed and was tested in a large phase II clinical trial (EBL2001) as part of the EBOVAC2 consortium. Here, we perform bulk sequencing of the variable heavy chain (VH) of B cell receptors (BCR) in forty participants from the EBL2001 trial in order to characterize the BCR repertoire in response to vaccination with Ad26.ZEBOV/MVA-BN-Filo. We develop a comprehensive database, EBOV-AbDab, of publicly available Ebolavirus-specific antibody sequences. We then use our database to predict the antigen-specific component of the vaccinee repertoires. Our results show striking convergence in VH germline gene usage across participants following the MVA-BN-Filo dose, and provide further evidence of the role of IGHV3-15 and IGHV3-13 antibodies in the B cell response to Ebolavirus glycoprotein. Furthermore, we found that previously described Ebola-specific mAb sequences present in EBOV-AbDab were sufficient to describe at least one of the ten most expanded BCR clonotypes in more than two thirds of our cohort of vaccinees following the boost, providing proof of principle for the utility of computational mining of immune repertoires.


Asunto(s)
Vacunas contra el Virus del Ébola , Ebolavirus , Fiebre Hemorrágica Ebola , Receptores de Antígenos de Linfocitos B , Vacunación , Humanos , Vacunas contra el Virus del Ébola/inmunología , Vacunas contra el Virus del Ébola/administración & dosificación , Fiebre Hemorrágica Ebola/inmunología , Fiebre Hemorrágica Ebola/prevención & control , Ebolavirus/inmunología , Receptores de Antígenos de Linfocitos B/inmunología , Receptores de Antígenos de Linfocitos B/genética , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Biología Computacional/métodos , Adulto , Masculino , Linfocitos B/inmunología , Femenino , Minería de Datos
20.
Int J Hematol ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888812

RESUMEN

Asciminib is a first-in-class BCR::ABL1 inhibitor that Specifically Targets the ABL1 Myristoyl Pocket (STAMP). It is approved worldwide and in Japan for chronic myeloid leukemia in chronic phase (CML-CP) with resistance or intolerance to previous tyrosine kinase inhibitor (TKI) therapy. In the Phase 3 ASCEMBL study, patients with CML-CP who received ≥ 2 prior ATP-competitive TKIs were randomized (2:1) to asciminib 40 mg twice-daily or bosutinib 500 mg once-daily. Here, we report the 96-week results of the subgroup analysis of Japanese patients (asciminib, n = 13; bosutinib, n = 3) in the ASCEMBL study. The MMR rate at Week 96 was 46.2% in asciminib-treated patients, increasing from Weeks 24 and 48. Patients who achieved MMR at Week 24 remained in MMR up to the Week 96 cutoff. While a high proportion of patients treated with asciminib remained on treatment at cutoff, none randomized to bosutinib were on treatment at Week 96. Despite the longer duration of exposure to asciminib, its safety and tolerability continued to be favorable with no new or worsening safety findings. Overall, the efficacy and safety outcomes in the Japanese subgroup were comparable with the ASCEMBL global study population, which supports the use of asciminib in Japanese patients with previously treated CML-CP.

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