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Leukemia Jun 2024Germline heterozygous mutations in DDX41 predispose individuals to hematologic malignancies in adulthood. Most of these DDX41 mutations result in a truncated protein,...
Germline heterozygous mutations in DDX41 predispose individuals to hematologic malignancies in adulthood. Most of these DDX41 mutations result in a truncated protein, leading to loss of protein function. To investigate the impact of these mutations on hematopoiesis, we generated mice with hematopoietic-specific knockout of one Ddx41 allele. Under normal steady-state conditions, there was minimal effect on lifelong hematopoiesis, resulting in a mild yet persistent reduction in red blood cell counts. However, stress induced by transplantation of the Ddx41 BM resulted in hematopoietic stem/progenitor cell (HSPC) defects and onset of hematopoietic failure upon aging. Transcriptomic analysis of HSPC subsets from the transplanted BM revealed activation of cellular stress responses, including upregulation of p53 target genes in erythroid progenitors. To understand how the loss of p53 affects the phenotype of Ddx41 HSPCs, we generated mice with combined Ddx41 and Trp53 heterozygous deletions. The reduction in p53 expression rescued the fitness defects in HSPC caused by Ddx41 heterozygosity. However, the combined Ddx41 and Trp53 mutant mice were prone to developing hematologic malignancies that resemble human myelodysplastic syndrome and acute myeloid leukemia. In conclusion, DDX41 heterozygosity causes dysregulation of the response to hematopoietic stress, which increases the risk of transformation with a p53 mutation.
PubMed: 38937548
DOI: 10.1038/s41375-024-02304-9 -
Discover Oncology Jun 2024Acute myeloid leukemia, constituting a majority of leukemias, grapples with a 24% 5-year survival rate. Recent strides in research have unveiled fresh targets for drug...
BACKGROUND
Acute myeloid leukemia, constituting a majority of leukemias, grapples with a 24% 5-year survival rate. Recent strides in research have unveiled fresh targets for drug therapies. LIM-only, a pivotal transcription factor within LIM proteins, oversees cell development and is implicated in tumor formation. Among these critical LIM proteins, CSRP1, a Cysteine-rich protein, emerges as a significant player in various diseases. Despite its recognition as a potential prognostic factor and therapeutic target in various cancers, the specific link between CSRP1 and acute myeloid leukemia remains unexplored. Our previous work, identifying CSRP1 in a prognostic model for AML patients, instigates a dedicated exploration into the nuanced role of CSRP1 in acute myeloid leukemia.
METHODS
R tool was conducted to analyze the public data. qPCR was applied to evaluate the expression of CSRP1 mRNA for clinical samples and cell line. Unpaired t test, Wilcoxon Rank Sum test, KM curves, spearman correlation test and Pearson correlation test were included in this study.
RESULTS
CSRP1 displays notable expression variations between normal and tumor samples in acute myeloid leukemia (AML). It stands out as an independent prognostic factor for AML patients, showing correlations with clinical factors like age and cytogenetics risk. Additionally, CSRP1 correlates with immune-related pathways, immune cells, and immune checkpoints in AML. Furthermore, the alteration of CSRP1 mRNA levels is observed upon treatment with a DNMT1 inhibitor for THP1 cells.
CONCLUSION
The CSRP1 has potential as a novel prognostic factor and appears to influence the immune response in acute myeloid leukemia. Additionally, there is an observed association between CSRP1 and DNA methylation in acute myeloid leukemia.
PubMed: 38937285
DOI: 10.1007/s12672-024-01088-9 -
British Journal of Haematology Jun 2024
PubMed: 38937136
DOI: 10.1111/bjh.19577 -
Journal of Medical Genetics Jun 2024Tatton-Brown-Rahman syndrome (TBRS; OMIM 615879), also known as DNA methyltransferase 3 alpha ()-overgrowth syndrome (DOS), was first described by Tatton-Brown in 2014....
BACKGROUND
Tatton-Brown-Rahman syndrome (TBRS; OMIM 615879), also known as DNA methyltransferase 3 alpha ()-overgrowth syndrome (DOS), was first described by Tatton-Brown in 2014. This syndrome is characterised by overgrowth, intellectual disability and distinctive facial features and is the consequence of germline loss-of-function variants in , which encodes a DNA methyltransferase involved in epigenetic regulation. Somatic variants of are frequently observed in haematological malignancies, including acute myeloid leukaemia (AML). To date, 100 individuals with TBRS with de novo germline variants have been described. We aimed to further characterise this disorder clinically and at the molecular level in a nationwide series of 24 French patients and to investigate the correlation between the severity of intellectual disability and the type of variant.
METHODS
We collected genetic and medical information from 24 individuals with TBRS using a questionnaire released through the French National AnDDI-Rares Network.
RESULTS
Here, we describe the first nationwide French cohort of 24 individuals with germline likely pathogenic/pathogenic variants in , including 17 novel variants. We confirmed that the main phenotypic features were intellectual disability (100% of individuals), distinctive facial features (96%) and overgrowth (87%). We highlighted novel clinical features, such as hypertrichosis, and further described the neurological features and EEG results.
CONCLUSION
This study of a nationwide cohort of individuals with TBRS confirms previously published data and provides additional information and clarifies clinical features to facilitate diagnosis and improve care. This study adds value to the growing body of knowledge on TBRS and broadens its clinical and molecular spectrum.
PubMed: 38937076
DOI: 10.1136/jmg-2024-110031 -
The Lancet. Haematology Jul 2024
Topics: Humans; Thrombocythemia, Essential; Leukemia, Erythroblastic, Acute
PubMed: 38937028
DOI: 10.1016/S2352-3026(24)00134-0 -
In Vivo (Athens, Greece) 2024ClFdA is a second-generation antineoplastic agent that has demonstrated significant anticancer activity, particularly against acute lymphoblastic leukemia and has been... (Review)
Review
BACKGROUND/AIM
ClFdA is a second-generation antineoplastic agent that has demonstrated significant anticancer activity, particularly against acute lymphoblastic leukemia and has been shown to have radiosensitizing activity. The aim of the study was to explore the genotoxic, cytotoxic and radiosensitizing effects of clofarabine (ClFdA) on bone marrow cells (BMCs), normoblasts and leukocytes of mice in vivo.
MATERIALS AND METHODS
Cytotoxicity was determined by the reduction in reticulocytes (RET), and genotoxicity was determined by the induction of micronucleated reticulocytes (MN-RET) in the peripheral blood and by DNA break induction in leukocytes determined by single-cell gel electrophoresis (SCGE). The radiosensitizing capacity of ClFdA was determined in leukocytes and BMCs by SCGE.
RESULTS
Two mechanisms of MN-RET induction were identified according to the antecedents, that could be due to inhibition of DNA synthesis and demethylation of G-C regions, and subsequent chromosome fragility. ClFdA cytotoxicity causes two contiguous peaks, an early peak that seems to inhibit MN-RET induction and a second peak that seems to be caused by ribonucleotide reductase (RR) and/or DNA synthesis inhibitions. ClFdA induced early DNA damage in noncycling leukocytes, and also radiosensitizes leukocytes immediately after treatment. ClFdA-ionizing radiation (IR) causes two time-dependent episodes of DNA damage, the latest after 80 min triggers a major breakage of DNA. In terms of the number of damaged cells, leukocytes and BMCs are similarly sensitive to ionizing radiation; BMCs are slightly more sensitive than leukocytes to ClFdA, but BMCs are doubly sensitive to combined treatment.
CONCLUSION
ClFdA causes early DNA damage and radiosensitivity in non-proliferating leukocytes, which rules out the most favored hypotheses of the participation of RR and DNA polymerase inhibition.
Topics: Animals; Clofarabine; Mice; Radiation-Sensitizing Agents; Leukocytes; DNA Damage; Arabinonucleosides; Bone Marrow Cells; Adenine Nucleotides; Male; Reticulocytes; Antineoplastic Agents; Micronucleus Tests
PubMed: 38936939
DOI: 10.21873/invivo.13622 -
In Vivo (Athens, Greece) 2024Acute myeloid leukemia (AML) is a myeloproliferative neoplasm marked by abnormal clonal expansion of hematopoietic progenitor cells, displaying karyotypic aberrations...
BACKGROUND/AIM
Acute myeloid leukemia (AML) is a myeloproliferative neoplasm marked by abnormal clonal expansion of hematopoietic progenitor cells, displaying karyotypic aberrations and genetic mutations as prognostic indicators. The World Health Organization (WHO) and the European LeukemiaNet guidelines categorize BCR::ABL1 p190+ AML as high risk. This study explored the identification of the increased incidence of BCR::ABL1 p190+ in our AML population.
PATIENTS AND METHODS
This study included 96 AML patients stratified according to WHO guidelines. Subsequently, patients were screened for genetic abnormalities, such as BCR::ABL1 p 190+, PML::RARA, RUNX1::RUNX1T1, and CBFB::MYH11 by quantitative reverse transcription polymerase chain reaction (RT-qPCR) analysis.
RESULTS
Among 96 AML patients, 36 displayed BCR::ABL1 p190+, overcoming the expected global incidence. Age variations (19 to 78 years) showed no significant laboratory differences between BCR::ABL1 p190+ and non-BCR::ABL p190+ cases. The overall survival analysis revealed no statistically significant differences among the patients (p=0.786).
CONCLUSION
The analyzed population presented a higher frequency of BCR::ABL1 p190+ detection in adult AML patients when compared to what is described in the worldwide literature. Therefore, more studies are needed to establish the reason why this incidence is higher and what the best treatment approach should be in these cases.
Topics: Humans; Adult; Leukemia, Myeloid, Acute; Middle Aged; Male; Female; Fusion Proteins, bcr-abl; Aged; Prognosis; Young Adult; Mutation
PubMed: 38936913
DOI: 10.21873/invivo.13659 -
In Vivo (Athens, Greece) 2024Hematotoxicity is a life-threatening condition that has become the major cause of drug discontinuation in patients with acute lymphoblastic leukemia (ALL). The nudix...
BACKGROUND/AIM
Hematotoxicity is a life-threatening condition that has become the major cause of drug discontinuation in patients with acute lymphoblastic leukemia (ALL). The nudix hydrolase 15 (NUDT15) gene polymorphism (c.415C>T) is reported to have an association with the hematotoxicity of 6-mercaptopurine (6-MP) as maintenance therapy in patients with ALL. However, the prevalence of this genetic polymorphism in the Indonesian population is unknown. This study aimed to assess the frequency of NUDT15 polymorphism among Indonesian pediatric patients with ALL and its association with the hematotoxicity of 6-MP.
PATIENTS AND METHODS
A total of 101 stored DNA samples from pediatric patients with ALL receiving 6-MP treatment were used for genetic testing. Direct sequencing was conducted to determine the NUDT15 c.415C>T genotype. Chi-square or Fisher's exact test were employed to examine the association between the NUDT15 c.415C>T genotype and hematotoxicity.
RESULTS
All (100%) of the DNA samples from patients with ALL treated with 6-MP exhibited a homozygous variant of the NUDT15 c.415C>T genotype, 70.3% of which showed hematotoxicity to some extent. We found no significant differences in NUDT15 gene polymorphism among patients with ALL with different states of hematotoxicity.
CONCLUSION
The observed high frequency of NUDT15 c.415C>T in our study population might explain the elevated prevalence of 6-MP-associated hematotoxicity in pediatric patients with ALL within the Indonesian population. Our study provides new insight regarding the NUDT15 gene polymorphism and its relation to hematotoxicity. Further studies are required to determine the necessity of adjusting the initial dose of 6-MP for Indonesian pediatric patients with ALL.
Topics: Adolescent; Child; Child, Preschool; Female; Humans; Infant; Male; Alleles; Antimetabolites, Antineoplastic; Gene Frequency; Genetic Predisposition to Disease; Genotype; Indonesia; Mercaptopurine; Nudix Hydrolases; Polymorphism, Single Nucleotide; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Pyrophosphatases
PubMed: 38936894
DOI: 10.21873/invivo.13662 -
In Vivo (Athens, Greece) 2024To date, therapeutic options for T-cell acute lymphoblastic leukemia (T-ALL) remain very limited. This study evaluated the efficacy of monotherapies and combination...
BACKGROUND/AIM
To date, therapeutic options for T-cell acute lymphoblastic leukemia (T-ALL) remain very limited. This study evaluated the efficacy of monotherapies and combination therapies including a selective BCL-2 inhibitor for T-ALL cell lines, namely Jurkat, CCRF-CEM, and Loucy.
MATERIALS AND METHODS
Loucy is an early T-precursor ALL (ETP-ALL) cell line characterized by an immature phenotype, whereas Jurkat and CCRF-CEM are late T-cell progenitor ALL (LTP-ALL) cell lines. Monotherapy was conducted with venetoclax, cytarabine, bendamustine, or azacytidine, whereas combination therapy was performed with venetoclax plus cytarabine, venetoclax plus bendamustine, or venetoclax plus azacytidine. Cell viability assay was conducted after 48 h using Trypan blue and the 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS). Statistical analysis for evaluating synergistic interactions between anticancer drugs was performed by using the SynergyFinder Plus and drc R package.
RESULTS
Adding venetoclax to cytarabine, bendamustine, or azacitidine achieved an additive effect, with Loewe synergic scores ranging from -10 to 10 in Jurkat and CCRF-CEM. Conversely, the combination of venetoclax and cytarabine displayed an additive effect (Loewe synergic score: 8.45 and 5.82 with MTS and Trypan blue assays, respectively), whereas venetoclax plus bendamustine or azacitidine exhibited a synergistic effect (Loewe synergic score >10 with MTS assay) in Loucy. Remarkably, the Bliss/Loewe score revealed that the combination of venetoclax and bendamustine was the most synergistic, yielding a score of 13.832±0.55.
CONCLUSION
The combination of venetoclax and bendamustine demonstrated the greatest synergistic effect in suppressing ETP-ALL cell proliferation. Further studies are warranted to determine the mechanisms for the synergism between venetoclax and bendamustine in high-risk T-ALL.
Topics: Humans; Bendamustine Hydrochloride; Bridged Bicyclo Compounds, Heterocyclic; Sulfonamides; Drug Synergism; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Cell Survival; Jurkat Cells; Apoptosis; Cell Proliferation
PubMed: 38936885
DOI: 10.21873/invivo.13624 -
JMIR Bioinformatics and Biotechnology Jun 2023There is a great need to develop a computational approach to analyze and exploit the information contained in gene expression data. The recent utilization of nonnegative...
Decision of the Optimal Rank of a Nonnegative Matrix Factorization Model for Gene Expression Data Sets Utilizing the Unit Invariant Knee Method: Development and Evaluation of the Elbow Method for Rank Selection.
BACKGROUND
There is a great need to develop a computational approach to analyze and exploit the information contained in gene expression data. The recent utilization of nonnegative matrix factorization (NMF) in computational biology has demonstrated the capability to derive essential details from a high amount of data in particular gene expression microarrays. A common problem in NMF is finding the proper number rank (r) of factors of the degraded demonstration, but no agreement exists on which technique is most appropriate to utilize for this purpose. Thus, various techniques have been suggested to select the optimal value of rank factorization (r).
OBJECTIVE
In this work, a new metric for rank selection is proposed based on the elbow method, which was methodically compared against the cophenetic metric.
METHODS
To decide the optimum number rank (r), this study focused on the unit invariant knee (UIK) method of the NMF on gene expression data sets. Since the UIK method requires an extremum distance estimator that is eventually employed for inflection and identification of a knee point, the proposed method finds the first inflection point of the curvature of the residual sum of squares of the proposed algorithms using the UIK method on gene expression data sets as a target matrix.
RESULTS
Computation was conducted for the UIK task using gene expression data of acute lymphoblastic leukemia and acute myeloid leukemia samples. Consequently, the distinct results of NMF were subjected to comparison on different algorithms. The proposed UIK method is easy to perform, fast, free of a priori rank value input, and does not require initial parameters that significantly influence the model's functionality.
CONCLUSIONS
This study demonstrates that the elbow method provides a credible prediction for both gene expression data and for precisely estimating simulated mutational processes data with known dimensions. The proposed UIK method is faster than conventional methods, including metrics utilizing the consensus matrix as a criterion for rank selection, while achieving significantly better computational efficiency without visual inspection on the curvatives. Finally, the suggested rank tuning method based on the elbow method for gene expression data is arguably theoretically superior to the cophenetic measure.
PubMed: 38935969
DOI: 10.2196/43665