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1.
World J Pediatr ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112809

RESUMEN

BACKGROUND: Childhood cancer entails a heavy burden for patients and their families. Recent advances in overall survival rates have increasingly brought long-term quality of life into focus. Animal-assisted activities (AAAs) have long been hypothesized to alleviate the burden on pediatric patients and their peers in the hospital setting. However, their use in inpatient pediatric oncology has been a sensitive issue mainly due to the fear of infections, resulting in a lack of studies. This study presents data on the feasibility, safety, and efficacy of AAAs from a single German center. METHODS: Between 2018 and 2022, 60 patients (median age = 10.3 years) diagnosed with malignancy and undergoing treatment were visited by an intervention dog (total visits = 100). Patients were screened for infections as per hospital policy, with additional microbiological testing performed based on symptoms. The dog was screened for human pathogens and zoonoses. Microbial data and hospitalizations were analyzed from two months prior to the first visit until two months after the last visit. Acceptance of being in the hospital, both with and without planned animal-assisted interventions and pre- and post-intervention state stress, were measured using a validated visual analogue scale (0-10). RESULTS: Patients benefited from AAAs, showing increased acceptance of being in the hospital (median: 7.25 vs. 4.50, P < 0.001) and decreased median state stress ratings one hour after the visit compared to one hour before the visit (1.00 vs. 4.25, P < 0.001). The intervention did not result in an increased number of infections or unplanned hospitalizations, and no zoonoses were detected. All microbial screening tests of the dog were negative. CONCLUSIONS: AAAs with visiting dogs in inpatient pediatric oncology are feasible and safe. Although they hold promise for enhancing patients' well-being, further prospective studies are needed. Supplementary file 2 (MP4 240076 KB).

2.
Blood Adv ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39121370

RESUMEN

Acute myeloid leukemia (AML) with the t(7;12)(q36;p13) translocation occurs only in very young children and has a poor clinical outcome. The expected oncofusion between breakpoint partners (MNX1 and ETV6) has only been reported in a subset of cases. However, a universal feature is the strong transcript and protein expression of MNX1, a homeobox transcription factor that is normally not expressed in hematopoietic cells. Here, we map the translocation breakpoints on chromosomes 7 and 12 in affected patients to a region proximal to MNX1 and either introns 1 or 2 of ETV6. The frequency of MNX1 overexpression in pediatric AML (n=1556, own and published data) is 2.4% and occurs predominantly in t(7;12)(q36;p13) AML. Chromatin interaction assays in a t(7;12)(q36;p13) iPSC cell line model unravel an enhancer-hijacking event that explains MNX1 overexpression in hematopoietic cells. Our data suggest that enhancer-hijacking may be a more widespread consequence of translocations where no oncofusion product was identified, including e.g. t(1;3) or t(4;12) AML.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39141058

RESUMEN

BACKGROUND: Vitamin D deficiency is linked to poor cancer outcomes, but the impact of its consequence, elevated parathyroid hormone (PTH) remains understudied. PTH receptor activation influences cancer progression in vitro, yet the effect of elevated PTH on pediatric cancer survival is unexamined. METHODS: This retrospective study examines associations between PTH, 25-OH vitamin D (25OHD), and event-free survival (EFS) and overall survival (OS) in pediatric cancer patients. Laboratory data from 4,349 patients (0-18 years) at a tertiary pediatric cancer unit were analyzed for the highest PTH and lowest 25OHD levels at diagnosis and the following five years. Data on relapse, secondary malignancies, and mortality were stratified by PTH levels above/below the cohort median (47 pg/ml) and 25OHD levels ≤ 30 nmol/L. EFS and OS were analyzed, and hazard ratios (HR) were calculated for the entire cohort and six cancer subgroups. RESULTS: PTH and 25OHD values were available for 1,286 patients (731 male). Higher PTH associated with inferior EFS in primary malignant brain tumors (HR 1.80 [1.19-2.72]), embryonal (HR 2.20 [1.1-4.43]), and lymphatic malignancies (HR 1.98 [1.05-3.72]). Vitamin D deficiency associated with inferior EFS in embryonal malignancies (HR 2.41 [1.24-4.68]). In a multivariate Cox model, only higher PTH remained significant for inferior EFS. CONCLUSIONS: Elevated PTH may indicate adverse outcomes in certain pediatric cancers. IMPACT: This study identifies elevated parathyroid hormone (PTH) as a potential marker for poor outcomes in pediatric cancer patients, emphasizing the need for adequate vitamin D and calcium management.

4.
Leukemia ; 38(9): 1929-1937, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38965370

RESUMEN

Balanced rearrangements involving the KMT2A gene (KMT2Ar) are recurrent genetic abnormalities in acute myeloid leukemia (AML), but there is lack of consensus regarding the prognostic impact of different fusion partners. Moreover, prognostic implications of gene mutations co-occurring with KMT2Ar are not established. From the HARMONY AML database 205 KMT2Ar adult patients were selected, 185 of whom had mutational information by a panel-based next-generation sequencing analysis. Overall survival (OS) was similar across the different translocations, including t(9;11)(p21.3;q23.3)/KMT2A::MLLT3 (p = 0.756). However, independent prognostic factors for OS in intensively treated patients were age >60 years (HR 2.1, p = 0.001), secondary AML (HR 2.2, p = 0.043), DNMT3A-mut (HR 2.1, p = 0.047) and KRAS-mut (HR 2.0, p = 0.005). In the subset of patients with de novo AML < 60 years, KRAS and TP53 were the prognostically most relevant mutated genes, as patients with a mutation of any of those two genes had a lower complete remission rate (50% vs 86%, p < 0.001) and inferior OS (median 7 vs 30 months, p < 0.001). Allogeneic hematopoietic stem cell transplantation in first complete remission was able to improve OS (p = 0.003). Our study highlights the importance of the mutational patterns in adult KMT2Ar AML and provides new insights into more accurate prognostic stratification of these patients.


Asunto(s)
Cromosomas Humanos Par 11 , N-Metiltransferasa de Histona-Lisina , Leucemia Mieloide Aguda , Mutación , Proteína de la Leucemia Mieloide-Linfoide , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/terapia , Proteína de la Leucemia Mieloide-Linfoide/genética , N-Metiltransferasa de Histona-Lisina/genética , Persona de Mediana Edad , Pronóstico , Adulto , Femenino , Masculino , Cromosomas Humanos Par 11/genética , Anciano , Adulto Joven , Translocación Genética , Reordenamiento Génico , Adolescente , Anciano de 80 o más Años , Tasa de Supervivencia , Secuenciación de Nucleótidos de Alto Rendimiento
5.
Nat Commun ; 15(1): 6025, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39019934

RESUMEN

Therapy-related myeloid neoplasms (t-MN) arise as a complication of chemo- and/or radiotherapy. Although t-MN can occur both in adult and childhood cancer survivors, the mechanisms driving therapy-related leukemogenesis likely vary across different ages. Chemotherapy is thought to induce driver mutations in children, whereas in adults pre-existing mutant clones are selected by the exposure. However, selective pressures induced by chemotherapy early in life are less well studied. Here, we use single-cell whole genome sequencing and phylogenetic inference to show that the founding cell of t-MN in children starts expanding after cessation of platinum exposure. In patients with Li-Fraumeni syndrome, characterized by a germline TP53 mutation, we find that the t-MN already expands during treatment, suggesting that platinum-induced growth inhibition is TP53-dependent. Our results demonstrate that germline aberrations can interact with treatment exposures in inducing t-MN, which is important for the development of more targeted, patient-specific treatment regimens and follow-up.


Asunto(s)
Mutación de Línea Germinal , Síndrome de Li-Fraumeni , Neoplasias Primarias Secundarias , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Síndrome de Li-Fraumeni/genética , Niño , Neoplasias Primarias Secundarias/genética , Masculino , Femenino , Compuestos de Platino/uso terapéutico , Adulto , Adolescente , Secuenciación Completa del Genoma , Filogenia , Preescolar , Antineoplásicos/uso terapéutico , Análisis de la Célula Individual
6.
Pediatr Blood Cancer ; 71(9): e31141, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38965693

RESUMEN

Treatment of relapsed and refractory myeloid leukemia in Down syndrome (r/r ML-DS) poses significant challenges, as prognosis is dire and there is no established standard treatment. This guideline provides treatment recommendations based on a literature review and collection of expert opinions, aiming to improve overall and event-free survival of patients. Treatment options include fludarabine and cytarabine (FLA) ± gemtuzumab ozogamicin (GO), azacytidine (AZA) ± panobinostat, and hematopoietic stem cell transplantation (HSCT). Preferred approaches are AZA ± panobinostat for cases with low blast count or FLA ± GO for cases with high blast count, followed by HSCT after remission. Further research is crucial for the investigation of targeted therapies (e.g., BH3 mimetics, LSD1, JAK inhibitors).


Asunto(s)
Síndrome de Down , Trasplante de Células Madre Hematopoyéticas , Humanos , Síndrome de Down/complicaciones , Niño , Guías de Práctica Clínica como Asunto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/terapia , Leucemia Mieloide/terapia , Leucemia Mieloide/tratamiento farmacológico
7.
BMJ Open Sport Exerc Med ; 10(2): e001907, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38882207

RESUMEN

Objectives: Paediatric patients with cancer undergoing allogeneic haematopoietic stem cell transplantation (allo-HSCT) face a high risk for life-threatening infections and transplant-related complications. Therefore, these children should be in the best possible physical condition beforehand. The study aims to evaluate the fitness status before allo-HSCT and identify correlations between fitness, quality of life and fatigue, clinical data, and previous exercise sessions. Methods: Paediatric patients with cancer ≥4 years old, treated with allo-HSCT, were recruited for the ANIMAL trial ("Effects of a low vs. moderate intense exercise program on immune recovery during paediatric allo-HSCT.", DRKS ID:DRKS00019865). Assessed at admission for HSCT were (1) clinical and anthropometric data, (2) motor performance (strength, endurance and balance) and (3) psychological parameters. Values were compared with published reference values (normative data from the literature) of healthy children, and correlation analyses were conducted. Results: 22 paediatric patients undergoing pre-allo-HSCT (23% female, 9.4±4.5 years, 73% leukaemia) exhibited substantial reduced differences in all motor performance parameters, with up to -106%±98 (mean difference to reference value) in static stance, -37%±45 in sit-to-stand, -52%±16 in leg extension and -48%±22 in hand grip strength compared with reference values. Correlations were observed among age and fitness parameters, the number of inpatient days and fatigue, and many previous exercise sessions correlated with better hand grip strength. Conclusion: These results indicate a poorer fitness status in children before HSCT compared with healthy children, recommending the need for structured exercise programmes for children undergoing HSCT. Differently directed correlations between age/body mass index and endurance/strength and between exercise sessions and strength show the importance of individualised training recommendations and the effect of training.

8.
Cancers (Basel) ; 16(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38791915

RESUMEN

PURPOSE: Osteosarcoma may arise as a secondary cancer following leukemias or lymphomas. We intended to increase the knowledge about such rare events. PATIENTS AND METHODS: We searched the Cooperative Osteosarcoma Study Group's database for individuals who developed their osteosarcoma following a previous hematological malignancy. The presentation and treatment of both malignancies was investigated, and additional neoplasms were noted. Outcomes after osteosarcoma were analyzed and potential prognostic factors were searched for. RESULTS: A total of 33 eligible patients were identified (male: 23, female: 10; median age: 12.9 years at diagnosis of hematological cancer; 20 lymphomas, 13 leukemias). A cancer predisposition syndrome was evident in one patient only. The hematological cancers had been treated by radiotherapy in 28 (1 unknown) and chemotherapy in 26 cases, including bone-marrow transplantation in 9. The secondary bone sarcomas (high-grade central 27, periosteal 2, extra-osseous 2, undifferentiated pleomorphic sarcoma of bone 2) arose after a median lag-time of 9.4 years, when patients were a median of 19.1 years old. Tumors were considered radiation-related in 26 cases (1 unknown). Osteosarcoma-sites were in the extremities (19), trunk (12), or head and neck (2). Metastases at diagnosis affected eight patients. Information on osteosarcoma therapy was available for 31 cases. All of these received chemotherapy. Local therapy involved surgery in 27 patients, with a good response reported for 9/18 eligible patients. Local radiotherapy was given to three patients. The median follow-up was 3.9 (0.3-12.0) years after bone tumor diagnosis. During this period, 21 patients had developed events as defined, and 15 had died, resulting in 5-year event-free and overall survival rates of 40% (standard error: 9%) and 56% (10%), respectively. There were multiple instances of additional neoplasms. Several factors were found to be of prognostic value (p < 0.05) for event-free (osteosarcoma site in the extremities) or overall (achievement of a surgical osteosarcoma-remission, receiving chemotherapy for the hematologic malignancy) survival. CONCLUSIONS: We were able to prove radiation therapy for hematological malignancies to be the predominant risk factor for later osteosarcomas. A resulting overrepresentation of axial and a tendency towards additional neoplasms affects prognosis. Still, selected patients may become long-term survivors with appropriate therapies, which is an argument against therapeutic negligence.

9.
Klin Padiatr ; 236(3): 165-172, 2024 May.
Artículo en Alemán | MEDLINE | ID: mdl-38437869

RESUMEN

BACKGROUND: About 2,200 children and adolescents in Germany per year are diagnosed with oncological diseases. Through now, there are almost no offers for home care services for these patients. There is a pilot program offering hospital-based home care for children and adolescents with cancer in Germany. The perspective of the parents will be researched by a qualitative exploring study. PATIENTS: In this interview study parents from children with cancer will be interviewed. METHOD: A qualitative exploring interview study, seeking the subjective perspective from parents on the hospital-based home care for children with cancer. The sample was drawn criterion-guided. The interviews were transcribed verbatim and analysed using qualitative content analysis. For socio- demographic characteristics the participants respond to an online questionnaire. RESULTS: Eleven women and three men aged between 30 and 60 years participated in the interviews. The average age of the ill children was 8.43 years. Five parents state that the children's illness did not lead to a reduction in working hours or to the termination of the employment relationship. Hospital-based home care results in subjectively perceived relief in everyday family life, especially in terms of time. Furthermore, a reduction in the psychological perception of stress is described. DISCUSSION/CONCLUSION: Due to the study design, the results presented here are to be regarded as indicative. In future studies the presented results should be supplemented by quantitative representative studies.


Asunto(s)
Servicios de Atención a Domicilio Provisto por Hospital , Neoplasias , Padres , Humanos , Femenino , Masculino , Niño , Neoplasias/psicología , Neoplasias/terapia , Alemania , Adulto , Adolescente , Padres/psicología , Persona de Mediana Edad , Investigación Cualitativa , Preescolar , Encuestas y Cuestionarios , Proyectos Piloto
10.
J Extracell Vesicles ; 13(3): e12417, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38499475

RESUMEN

Small extracellular vesicles (sEVs) released by acute myeloid leukaemia (AML) cells have been reported to influence the trilineage differentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs). However, it remains elusive which biological cargo from AML-sEVs is responsible for this effect. In this study, sEVs were isolated from cell-conditioned media and blood plasma using size-exclusion chromatography and ultrafiltration and characterized according to MISEV2018 guidelines. Our results demonstrated that AML-sEVs increased the proliferation of BM-MSCs. Conversely, key proteins that are important for normal haematopoiesis were downregulated in BM-MSCs. Additionally, we revealed that AML-sEVs significantly reduced the differentiation of BM-MSCs to osteoblasts without affecting adipogenic or chondrogenic differentiation. Next, LC-MS/MS proteomics elucidated that various proteins, including Y-box-binding protein 1 (YBX1), were upregulated in both AML-sEVs and BM-MSCs treated with AML-sEVs. Clinically relevant, we found that YBX1 is considerably upregulated in most paediatric AML patient-derived sEVs compared to healthy controls. Interestingly, sEVs isolated after the downregulation of YBX1 in AML cells remarkably rescued the osteoblastic differentiation of BM-MSCs. Altogether, our data demonstrate for the first time that YBX1 containing AML-sEVs is one of the key players that disrupt the normal function of bone marrow microenvironment by reducing the osteogenic differentiation of BM-MSCs.


Asunto(s)
Vesículas Extracelulares , Leucemia Mieloide Aguda , Células Madre Mesenquimatosas , Niño , Humanos , Cromatografía Liquida , Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Osteoblastos , Osteogénesis , Espectrometría de Masas en Tándem , Microambiente Tumoral , Proteína 1 de Unión a la Caja Y/metabolismo
11.
Sci Rep ; 14(1): 2034, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263339

RESUMEN

Glioblastoma presents characteristically with an exuberant, poorly functional vasculature that causes malperfusion, hypoxia and necrosis. Despite limited clinical efficacy, anti-angiogenesis resulting in vascular normalization remains a promising therapeutic approach. Yet, fundamental questions concerning anti-angiogenic therapy remain unanswered, partly due to the scale and resolution gap between microscopy and clinical imaging and a lack of quantitative data readouts. To what extend does treatment lead to vessel regression or vessel normalization and does it ameliorate or aggravate hypoxia? Clearly, a better understanding of the underlying mechanisms would greatly benefit the development of desperately needed improved treatment regimens. Here, using orthotopic transplantation of Gli36 cells, a widely used murine glioma model, we present a mesoscopic approach based on light sheet fluorescence microscopic imaging of wholemount stained tumors. Deep learning-based segmentation followed by automated feature extraction allowed quantitative analyses of the entire tumor vasculature and oxygenation statuses. Unexpectedly in this model, the response to both cytotoxic and anti-angiogenic therapy was dominated by vessel normalization with little evidence for vessel regression. Equally surprising, only cytotoxic therapy resulted in a significant alleviation of hypoxia. Taken together, we provide and evaluate a quantitative workflow that addresses some of the most urgent mechanistic questions in anti-angiogenic therapy.


Asunto(s)
Aprendizaje Profundo , Glioblastoma , Glioma , Animales , Ratones , Inmunoterapia , Hipoxia
12.
IEEE Trans Neural Netw Learn Syst ; 35(3): 3168-3180, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37053066

RESUMEN

Attitude control of fixed-wing unmanned aerial vehicles (UAVs) is a difficult control problem in part due to uncertain nonlinear dynamics, actuator constraints, and coupled longitudinal and lateral motions. Current state-of-the-art autopilots are based on linear control and are thus limited in their effectiveness and performance. Gls drl is a machine learning method to automatically discover optimal control laws through interaction with the controlled system that can handle complex nonlinear dynamics. We show in this article that deep reinforcement learning (DRL) can successfully learn to perform attitude control of a fixed-wing UAV operating directly on the original nonlinear dynamics, requiring as little as 3 min of flight data. We initially train our model in a simulation environment and then deploy the learned controller on the UAV in flight tests, demonstrating comparable performance to the state-of-the-art ArduPlane proportional-integral-derivative (PID) attitude controller with no further online learning required. Learning with significant actuation delay and diversified simulated dynamics were found to be crucial for successful transfer to control of the real UAV. In addition to a qualitative comparison with the ArduPlane autopilot, we present a quantitative assessment based on linear analysis to better understand the learning controller's behavior.

13.
Bone Marrow Transplant ; 59(1): 107-116, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37925531

RESUMEN

Optimal conditioning prior to allogeneic hematopoietic stem cell transplantation for children with non-malignant diseases is subject of ongoing research. This prospective, randomized, phase 2 trial compared safety and efficacy of busulfan with treosulfan based preparative regimens. Children with non-malignant diseases received fludarabine and either intravenous (IV) busulfan (4.8 to 3.2 mg/kg/day) or IV treosulfan (10, 12, or 14 g/m2/day). Thiotepa administration (2 × 5 mg/kg) was at the investigator's discretion. Primary endpoint was freedom from transplantation (treatment)-related mortality (freedom from TRM), defined as death between Days -7 and +100. Overall, 101 patients (busulfan 50, treosulfan 51) with at least 12 months follow-up were analyzed. Freedom from TRM was 90.0% (95% CI: 78.2%, 96.7%) after busulfan and 100.0% (95% CI: 93.0%, 100.0%) after treosulfan. Secondary outcomes (transplantation-related mortality [12.0% versus 3.9%]) and overall survival (88.0% versus 96.1%) favored treosulfan. Graft failure was more common after treosulfan (n = 11), than after busulfan (n = 2) while all patients were rescued by second procedures except one busulfan patient. CTCAE Grade III adverse events were similar in both groups. This study confirmed treosulfan to be an excellent alternative to busulfan and can be safely used for conditioning treatment in children with non-malignant disease.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Niño , Humanos , Busulfano/uso terapéutico , Estudios Prospectivos , Acondicionamiento Pretrasplante/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Vidarabina/uso terapéutico , Enfermedad Injerto contra Huésped/etiología
14.
Leukemia ; 38(3): 538-544, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38086945

RESUMEN

New methods like panel-based RNA fusion sequencing (RNA-FS) promise improved diagnostics in various malignancies. We here analyzed the impact of RNA-FS on the initial diagnostics of 241 cases with pediatric acute myeloid leukemia (AML). We show that, compared to classical cytogenetics (CCG), RNA-FS reliably detected risk-relevant fusion genes in pediatric AML. In addition, RNA-FS strongly improved the detection of cryptic fusion genes like NUP98::NSD1, KMT2A::MLLT10 and CBFA2T3::GLIS2 and thereby resulted in an improved risk stratification in 25 patients (10.4%). Validation of additionally detected non-risk-relevant high confidence fusion calls identified PIM3::BRD1, C22orf34::BRD1, PSPC1::ZMYM2 and ARHGAP26::NR3C1 as common genetic variants and MYB::GATA1 as recurrent aberration, which we here describe in AML subtypes M0 and M7 for the first time. However, it failed to detect rare cytogenetically confirmed fusion events like MNX1::ETV6 and other chromosome 12p-abnormalities. As add-on benefit, the proportion of patients for whom measurable residual disease (MRD) monitoring became possible was increased by RNA-FS from 44.4 to 75.5% as the information on the fusion transcripts' sequence allowed the design of new MRD assays.


Asunto(s)
Leucemia Mieloide Aguda , Niño , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Perfilación de la Expresión Génica , ARN , Proteínas de Fusión Oncogénica/genética , Proteínas de Unión al ARN/genética , Factores de Transcripción/genética , Proteínas de Homeodominio/genética
15.
iScience ; 26(10): 107844, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37766974

RESUMEN

The noncoding genome presents a largely untapped source of new biological insights, including thousands of long noncoding RNA (lncRNA) loci. While lncRNA dysregulation has been reported in myeloid malignancies, their functional relevance remains to be systematically interrogated. We performed CRISPRi screens of lncRNA signatures from normal and malignant hematopoietic cells and identified MYNRL15 as a myeloid leukemia dependency. Functional dissection suggests an RNA-independent mechanism mediated by two regulatory elements embedded in the locus. Genetic perturbation of these elements triggered a long-range chromatin interaction and downregulation of leukemia dependency genes near the gained interaction sites, as well as overall suppression of cancer dependency pathways. Thus, this study describes a new noncoding myeloid leukemia vulnerability and mechanistic concept for myeloid leukemia. Importantly, MYNRL15 perturbation caused strong and selective impairment of leukemia cells of various genetic backgrounds over normal hematopoietic stem and progenitor cells in vitro, and depletion of patient-derived xenografts in vivo.

16.
Cell Genom ; 3(9): 100389, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37719152

RESUMEN

Detection of somatic mutations in single cells has been severely hampered by technical limitations of whole-genome amplification. Novel technologies including primary template-directed amplification (PTA) significantly improved the accuracy of single-cell whole-genome sequencing (WGS) but still generate hundreds of artifacts per amplification reaction. We developed a comprehensive bioinformatic workflow, called the PTA Analysis Toolbox (PTATO), to accurately detect single base substitutions, insertions-deletions (indels), and structural variants in PTA-based WGS data. PTATO includes a machine learning approach and filtering based on recurrence to distinguish PTA artifacts from true mutations with high sensitivity (up to 90%), outperforming existing bioinformatic approaches. Using PTATO, we demonstrate that hematopoietic stem cells of patients with Fanconi anemia, which cannot be analyzed using regular WGS, have normal somatic single base substitution burdens but increased numbers of deletions. Our results show that PTATO enables studying somatic mutagenesis in the genomes of single cells with unprecedented sensitivity and accuracy.

17.
Cancers (Basel) ; 15(13)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37444601

RESUMEN

WT1 is a true chameleon, both acting as an oncogene and tumor suppressor. As its exact role in leukemogenesis is still ambiguous, research with model systems representing natural conditions surrounding the genetic alterations in WT1 is necessary. In a cohort of 59 leukemia/lymphoma cell lines, we showed aberrant expression for WT1 mRNA, which does not always translate into protein levels. We also analyzed the expression pattern of the four major WT1 protein isoforms in the cell lines and primary AML blasts with/without WT1 mutations and demonstrated that the presence of mutations does not influence these patterns. By introduction of key intronic and exonic sequences of WT1 into a lentiviral expression vector, we developed a unique tool that can stably overexpress the four WT1 isoforms at their naturally occurring tissue-dependent ratio. To develop better cellular model systems for WT1, we sequenced large parts of its gene locus and also other important myeloid risk factor genes and revealed previously unknown alterations. Functionally, inhibition of the nonsense-mediated mRNA decay machinery revealed that under natural conditions, the mutated WT1 alleles go through a robust degradation. These results offer new insights and model systems regarding the characteristics of WT1 in leukemia and lymphoma.

18.
Leukemia ; 37(7): 1435-1443, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37188777

RESUMEN

In acute myeloid leukaemia (AML) RUNX1 mutation is characterised by certain clinicopathological features with poor prognosis and adverse risk by the European LeukemiaNet recommendation. Though initially considered as provisional category, the recent World Health Organisation (WHO) classification of 2022 removed RUNX1-mutated AML from the unique entity. However, the significance of RUNX1 mutation in paediatric AML remains unclear. We retrospectively analysed a German cohort of 488 paediatric patients with de novo AML, enroled in the AMLR12 or AMLR17 registry of the AML-BFM Study Group (Essen, Germany). A total of 23 paediatric AML patients (4.7%) harboured RUNX1 mutations, 18 of which (78%) had RUNX1 mutation at initial diagnosis. RUNX1 mutations were associated with older age, male gender, number of coexisting alterations and presence of FLT3-ITD but mutually exclusive of KRAS, KIT and NPM1 mutation. RUNX1 mutations did not prognostically impact overall or event-free survival. Response rates did not differ between patients with and without RUNX1 mutations. This comprehensive study, comprising the largest analysis of RUNX1 mutation in a paediatric cohort to date, reveals distinct but not unique clinicopathologic features, with no prognostic significance of RUNX1-mutated paediatric AML. These results broaden the perspective on the relevance of RUNX1 alterations in leukaemogenesis in AML.


Asunto(s)
Leucemia Mieloide Aguda , Nucleofosmina , Humanos , Masculino , Niño , Estudios Retrospectivos , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Mutación , Leucemia Mieloide Aguda/patología , Pronóstico
19.
Hum Mol Genet ; 32(11): 1836-1849, 2023 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-36721989

RESUMEN

Biallelic germline mutations in BRCA2 occur in the Fanconi anemia (FA)-D1 subtype of the rare pediatric disorder, FA, characterized clinically by severe congenital abnormalities and a very high propensity to develop malignancies early in life. Clinical and genetic data from 96 FA-D1 patients with biallelic BRCA2 mutations were collected and used to develop a new cancer risk prediction score system based on the specific mutations in BRCA2. This score takes into account the location of frameshift/stop and missense mutations relative to exon 11 of BRCA2, which encodes the major sites for interaction with the RAD51 recombinase, and uses the MaxEnt and HBond splicing scores to analyze potential splice site perturbations. Among 75 FA-D1 patients with ascertained BRCA2 mutations, 66 patients developed 102 malignancies, ranging from one to three independent tumors per individual. The median age at the clinical presentation of peripheral embryonal tumors was 1.0, at the onset of hematologic malignancies 1.8 and at the manifestation of CNS tumors 2.7 years, respectively. Patients who received treatment lived longer than those without. Using our novel scoring system, we could distinguish three distinct cancer risk groups among FA-D1 patients: in the first, patients developed their initial malignancy at a median age of 1.3 years (n = 36, 95% CI = 0.9-1.8), in the second group at 2.3 years (n = 17, 95% CI = 1.4-4.4) and in the third group at 23.0 years (n = 22, 95% CI = 4.3-n/a). Therefore, this scoring system allows, for the first time, to predict the cancer manifestation of FA-D1 patients simply based on the type and position of the mutations in BRCA2.


Asunto(s)
Anemia de Fanconi , Neoplasias , Humanos , Niño , Lactante , Anemia de Fanconi/genética , Proteína BRCA2/genética , Neoplasias/genética , Mutación , Recombinasa Rad51/genética
20.
Children (Basel) ; 10(2)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36832447

RESUMEN

(1) Background: Growing evidence indicates benefits through exercise programs in pediatric oncology throughout the whole cancer trajectory. This should include palliative care, too. This project analyzes the feasibility of a supervised exercise program offered during hospital and home-based care for children with advanced cancer diagnoses. (2) Methods: Four children (7-13 years old) with advanced cancer diagnoses participated in this project. It consisted of supervised exercise sessions offered once a week (30-90 min), mainly home-based, but also on an in- and outpatient basis. Regular data assessments included psychological and physical capacity-related endpoints and body composition. Details and contents of exercise sessions and adverse events were recorded. (3) Results: Exercise was feasible with 73 ± 9% adherence to the minimum number of planned sessions. The exercise offer was accepted until shortly before death. Effects on fatigue, quality of life and muscular endurance were noted. Participants showed major deviations from age-specific reference values. No exercise-related adverse events occurred. (4) Conclusions: The exercise program was safe, feasible, and might have served as a supportive tool to reduce overall burden. Evaluation of exercise as usual palliative care should be assessed by further studies.

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