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Pediatrics International : Official... 2024WAS gene mutational analysis is crucial to establish a definite diagnosis of Wiskott-Aldrich syndrome (WAS). Data on the genetic background of WAS in Vietnamese patients...
BACKGROUND
WAS gene mutational analysis is crucial to establish a definite diagnosis of Wiskott-Aldrich syndrome (WAS). Data on the genetic background of WAS in Vietnamese patients have not been reported.
METHODS
We recruited 97 male, unrelated patients with WAS and analyzed WAS gene mutation using Sanger sequencing technology.
RESULTS
We identified 36 distinct hemizygous pathogenic mutations, with 17 novel variants, from 38 patients in the entire cohort (39.2%). The mutational spectrum included 14 missense, 12 indel, five nonsense, four splicing, and one non-stop mutations. Most mutations appear only once, with the exception of c.37C>T (p.R13X) and c.374G>A (p.G125E) each of which occurs twice in unrelated patients.
CONCLUSION
Our data enrich the mutational spectrum of the WAS gene and are crucial for understanding the genetic background of WAS and for supporting genetic counseling.
Topics: Humans; Male; DNA Mutational Analysis; Mutation; Vietnam; Wiskott-Aldrich Syndrome; Wiskott-Aldrich Syndrome Protein
PubMed: 38641933
DOI: 10.1111/ped.15770 -
Clinical Immunology (Orlando, Fla.) Jun 2024T-ALL is an aggressive hematological tumor that develops as the result of a multi-step oncogenic process which causes expansion of hematopoietic progenitors that are...
Wiskott Aldrich syndrome protein (WASp)-deficient Th1 cells promote R-loop-driven transcriptional insufficiency and transcription-coupled nucleotide excision repair factor (TC-NER)-driven genome-instability in the pathogenesis of T cell acute lymphoblastic leukemia.
BACKGROUND
T-ALL is an aggressive hematological tumor that develops as the result of a multi-step oncogenic process which causes expansion of hematopoietic progenitors that are primed for T cell development to undergo malignant transformation and growth. Even though first-line therapy has a significant response rate, 40% of adult patients and 20% of pediatric patients will relapse. Therefore, there is an unmet need for treatment for relapsed/refractory T-ALL to develop potential targeted therapies.
METHODS
Pediatric T-ALL patient derived T cells were grown under either nonskewingTh0 or Th1-skewing conditions to further process for ChIP-qPCR, RDIP-qPCR and other RT-PCR assays. Endogenous WASp was knocked out using CRISPR-Cas9 and was confirmed using flow cytometry and western blotting. LC-MS/MS was performed to find out proteomic dataset of WASp-interactors generated from Th1-skewed, human primary Th-cells. DNA-damage was assessed by immunofluorescence confocal-imaging and single-cell gel electrophoresis (comet assay). Overexpression of RNaseH1 was also done to restore normal Th1-transcription in WASp-deficient Th1-skewed cells.
RESULTS
We discovered that nuclear-WASp is required for suppressing R-loop production (RNA/DNA-hybrids) at Th1-network genes by ribonucleaseH2 (RNH2) and topoisomerase1. Nuclear-WASp is associated with the factors involved in preventing and dissolving R-loops in Th1 cells. In nuclear- WASp-reduced malignant Th1-cells, R-loops accumulate in vivo and are processed into DNA-breaks by transcription-coupled-nucleotide-excision repair (TC-NER). Several epigenetic modifications were also found to be involved at Th1 gene locus which are responsible for active/repressive marks of particular genes. By demonstrating WASp as a physiologic regulator of programmed versus unprogrammed R-loops, we suggest that the transcriptional role of WASp in vivo extends also to prevent transcription-linked DNA damage during malignancy and through modification of epigenetic dysregulations.
CONCLUSION
Our findings present a provocative possibility of resetting R-loops as a therapeutic intervention to correct both immune deficiency and malignancy in T-cell acute lymphoblastic leukemia patients and a novel role of WASp in the epigenetic regulation of T helper cell differentiation in T-ALL patients, anticipating WASp's requirement for the suppression of T-ALL progression.
Topics: Humans; Th1 Cells; DNA Repair; Wiskott-Aldrich Syndrome Protein; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma; Genomic Instability; Transcription, Genetic; DNA Damage; Child; Excision Repair
PubMed: 38582251
DOI: 10.1016/j.clim.2024.110204 -
Blood Jun 2024Wiskott-Aldrich syndrome (WAS) is a multifaceted monogenic disorder with a broad disease spectrum and variable disease severity and a variety of treatment options...
Wiskott-Aldrich syndrome (WAS) is a multifaceted monogenic disorder with a broad disease spectrum and variable disease severity and a variety of treatment options including allogeneic hematopoietic stem cell transplantation (HSCT) and gene therapy (GT). No reliable biomarker exists to predict disease course and outcome for individual patients. A total of 577 patients with a WAS variant from 26 countries and a median follow-up of 8.9 years (range, 0.3-71.1), totaling 6118 patient-years, were included in this international retrospective study. Overall survival (OS) of the cohort (censored at HSCT or GT) was 82% (95% confidence interval, 78-87) at age 15 years and 70% (61-80) at 30 years. The type of variant was predictive of outcome: patients with a missense variant in exons 1 or 2 or with the intronic hot spot variant c.559+5G>A (class I variants) had a 15-year OS of 93% (89-98) and a 30-year OS of 91% (86-97), compared with 71% (62-81) and 48% (34-68) in patients with any other variant (class II; P < .0001). The cumulative incidence rates of disease-related complications such as severe bleeding (P = .007), life-threatening infection (P < .0001), and autoimmunity (P = .004) occurred significantly later in patients with a class I variant. The cumulative incidence of malignancy (P = .6) was not different between classes I and II. It confirms the spectrum of disease severity and quantifies the risk for specific disease-related complications. The class of the variant is a biomarker to predict the outcome for patients with WAS.
Topics: Humans; Adolescent; Child; Male; Wiskott-Aldrich Syndrome; Female; Child, Preschool; Adult; Retrospective Studies; Infant; Young Adult; Genotype; Biomarkers; Hematopoietic Stem Cell Transplantation; Severity of Illness Index; Wiskott-Aldrich Syndrome Protein; Follow-Up Studies; Middle Aged; Prognosis; Survival Rate
PubMed: 38579284
DOI: 10.1182/blood.2023021411 -
Oncology Research 2024Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid malignancies. A specific mechanism of its metastasis has not been established. In this study,...
Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid malignancies. A specific mechanism of its metastasis has not been established. In this study, we investigated whether Neural Wiskott-Aldrich syndrome protein (N-WASP) plays a role in distant metastasis of PDAC. We found that N-WASP is markedly expressed in clinical patients with PDAC. Clinical analysis showed a notably more distant metastatic pattern in the N-WASP-high group compared to the N-WASP-low group. N-WASP was noted to be a novel mediator of epithelial-mesenchymal transition (EMT) via gene expression profile studies. Knockdown of N-WASP in pancreatic cancer cells significantly inhibited cell invasion, migration, and EMT. We also observed positive association of lysyl oxidase-like 2 (LOXL2) and focal adhesion kinase (FAK) with the N-WASP-mediated response, wherein EMT and invadopodia function were modulated. Both N-WASP and LOXL2 depletion significantly reduced the incidence of liver and lung metastatic lesions in orthotopic mouse models of pancreatic cancer. These results elucidate a novel role for N-WASP signaling associated with LOXL2 in EMT and invadopodia function, with respect to regulation of intercellular communication in tumor cells for promoting pancreatic cancer metastasis. These findings may aid in the development of therapeutic strategies against pancreatic cancer.
Topics: Animals; Humans; Mice; Amino Acid Oxidoreductases; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Movement; Epithelial-Mesenchymal Transition; Focal Adhesion Protein-Tyrosine Kinases; Pancreatic Neoplasms; Signal Transduction; Wiskott-Aldrich Syndrome Protein
PubMed: 38560567
DOI: 10.32604/or.2024.044029 -
Cell Reports Apr 2024Attachment of circulating tumor cells to the endothelial cells (ECs) lining blood vessels is a critical step in cancer metastatic colonization, which leads to metastatic...
Attachment of circulating tumor cells to the endothelial cells (ECs) lining blood vessels is a critical step in cancer metastatic colonization, which leads to metastatic outgrowth. Breast and prostate cancers are common malignancies in women and men, respectively. Here, we observe that β1-integrin is required for human prostate and breast cancer cell adhesion to ECs under shear-stress conditions in vitro and to lung blood vessel ECs in vivo. We identify IQGAP1 and neural Wiskott-Aldrich syndrome protein (NWASP) as regulators of β1-integrin transcription and protein expression in prostate and breast cancer cells. IQGAP1 and NWASP depletion in cancer cells decreases adhesion to ECs in vitro and retention in the lung vasculature and metastatic lung nodule formation in vivo. Mechanistically, NWASP and IQGAP1 act downstream of Cdc42 to increase β1-integrin expression both via extracellular signal-regulated kinase (ERK)/focal adhesion kinase signaling at the protein level and by myocardin-related transcription factor/serum response factor (SRF) transcriptionally. Our results identify IQGAP1 and NWASP as potential therapeutic targets to reduce early metastatic dissemination.
Topics: Humans; Integrin beta1; ras GTPase-Activating Proteins; Neoplasm Metastasis; Cell Line, Tumor; Serum Response Factor; Male; Female; Prostatic Neoplasms; Animals; Trans-Activators; Cell Adhesion; Wiskott-Aldrich Syndrome Protein, Neuronal; Breast Neoplasms; Mice; Focal Adhesion Kinase 1; Gene Expression Regulation, Neoplastic; cdc42 GTP-Binding Protein
PubMed: 38536816
DOI: 10.1016/j.celrep.2024.113989 -
Pediatric Blood & Cancer Jun 2024Wiskott-Aldrich syndrome (WAS) is a rare X-linked inborn error of immunity characterized by microthrombocytopenia, infections, eczema, and increased predisposition to...
INTRODUCTION
Wiskott-Aldrich syndrome (WAS) is a rare X-linked inborn error of immunity characterized by microthrombocytopenia, infections, eczema, and increased predisposition to develop autoimmunity and malignancy. Flow cytometric assay for determining WAS protein (WASp) is a rapid and cost-effective tool for detecting patients. However, very few studies described WASp expression in female carriers. Most WAS carriers are clinically asymptomatic. Active screening of female family members helps identify female carriers, distinguish de novo mutations, and to select appropriate donor prior to curative stem cell transplantation. This study was undertaken to evaluate the diagnostic capability of flow cytometry-based WASp expression in peripheral blood cells to identify carriers and compare WASp expression in different blood cell lineages.
PATIENTS AND METHODS
Female patients, heterozygous for WAS gene, were enrolled in this study conducted at Pediatric Allergy Immunology Unit, Advanced Pediatric Centre, Post Graduate Institute of Medical Education and Research, Chandigarh, India. Flow cytometric assessment of WASp expression in lymphocytes, monocytes, and neutrophils was carried out and compared with healthy control and affected patients. The results were expressed in delta (Δ) median fluorescence intensity (MFI) as well as stain index (SI), which is the ratio of ΔMFI of patient and ΔMFI of control.
RESULTS
Thirteen mothers and two sisters of genetically confirmed WAS patients were enrolled in the study. All enrolled females were clinically asymptomatic and did not have microthrombocytopenia. Low WASp expression (SI < 1) was seen in lymphocytes and monocytes in 10 (66.6%) carriers. Females with variants in proximal exons (exons 1 and 2) were found to have lesser expression than those with distal (exons 3-12) variants.
CONCLUSION
Flow cytometry is a rapid, easily available, cost-effective tool for WASp estimation. Lymphocytes followed by monocytes are the best cell lineages for WASp estimation in carrier females. However, genetic testing remains the gold standard, as carrier females with variants in distal exons may have normal WASp expression.
PubMed: 38523275
DOI: 10.1002/pbc.30972 -
The Journal of Biological Chemistry Apr 2024The actin cytoskeleton and reactive oxygen species (ROS) both play crucial roles in various cellular processes. Previous research indicated a direct interaction between...
The actin cytoskeleton and reactive oxygen species (ROS) both play crucial roles in various cellular processes. Previous research indicated a direct interaction between two key components of these systems: the WAVE1 subunit of the WAVE regulatory complex (WRC), which promotes actin polymerization and the p47 subunit of the NADPH oxidase 2 complex (NOX2), which produces ROS. Here, using carefully characterized recombinant proteins, we find that activated p47 uses its dual Src homology 3 domains to bind to multiple regions within the WAVE1 and Abi2 subunits of the WRC, without altering WRC's activity in promoting Arp2/3-mediated actin polymerization. Notably, contrary to previous findings, p47 uses the same binding pocket to interact with both the WRC and the p22 subunit of NOX2, albeit in a mutually exclusive manner. This observation suggests that when activated, p47 may separately participate in two distinct processes: assembling into NOX2 to promote ROS production and engaging with WRC to regulate the actin cytoskeleton.
Topics: Humans; Actin Cytoskeleton; Actins; NADPH Oxidase 2; NADPH Oxidases; Protein Binding; Reactive Oxygen Species; Wiskott-Aldrich Syndrome Protein Family; Recombinant Proteins; Protein Subunits; Actin-Related Protein 2-3 Complex; Binding Sites
PubMed: 38432630
DOI: 10.1016/j.jbc.2024.107130 -
Molecular Therapy. Methods & Clinical... Mar 2024Wiskott-Aldrich syndrome (WAS) is a severe X-linked primary immunodeficiency resulting from a diversity of mutations distributed across all 12 exons of the gene....
Wiskott-Aldrich syndrome (WAS) is a severe X-linked primary immunodeficiency resulting from a diversity of mutations distributed across all 12 exons of the gene. encodes a hematopoietic-specific and developmentally regulated cytoplasmic protein (WASp). The objective of this study was to develop a gene correction strategy potentially applicable to most WAS patients by employing nuclease-mediated, site-specific integration of a corrective gene sequence into the endogenous chromosomal locus. In this study, we demonstrate the ability to target the integration of -containing constructs into intron 1 of the endogenous gene of primary CD34 hematopoietic stem and progenitor cells (HSPCs), as well as WASp-deficient B cell lines and WASp-deficient primary T cells. This intron 1 targeted integration (TI) approach proved to be quite efficient and restored WASp expression in treated cells. Furthermore, TI restored WASp-dependent function to WAS patient T cells. Edited CD34 HSPCs exhibited the capacity for multipotent differentiation to various hematopoietic lineages and in transplanted immunodeficient mice. This methodology offers a potential editing approach for treatment of WAS using patient's CD34 cells.
PubMed: 38414825
DOI: 10.1016/j.omtm.2024.101208 -
Cureus Jan 2024We present a case of a three-year-old African American male, born at term, who initially presented with bronchiolitis at six months and has since experienced recurrent...
Differential Diagnosis and Interdisciplinary Workup of a Pediatric Patient With an Unknown Immune Condition: Chronic Respiratory Distress Secondary to Viral Illness and Developmental Consequences.
We present a case of a three-year-old African American male, born at term, who initially presented with bronchiolitis at six months and has since experienced recurrent episodes of respiratory distress and hospitalizations. The patient also has severe eczema, developmental delays, and recurrent viral illnesses. Despite thorough evaluations from various specialists, such as pulmonology, allergy, and gastroenterology, the underlying cause remained elusive. The differential diagnosis for this case is as follows: severe persistent asthma with a possible link to genetic mutations such as CDHR3, hyper-IgE syndrome, atypical presentation of Wiskott-Aldrich syndrome, and severe gastroesophageal reflux disease (GERD) with aspiration pneumonitis. This patient's chronic condition has contributed to several developmental consequences, including failure to gain weight and possible hypoxic encephalopathy, leading to delays in cognitive and motor milestones and speech delays. Aggressive medical management, especially long-term systemic steroids, raises concerns about future complications. Through this case, we highlight the importance of thorough workups and an interdisciplinary approach to diagnosing and managing an unknown immune condition, as well as consistent pediatric primary care follow-up to assess development and coordinate necessary support. Here, we aim to address a gap in research on the unique presentations of pediatric respiratory distress symptoms by formulating a comprehensive differential diagnosis and exploring the various ways that chronic respiratory illness can contribute to developmental deficits such as speech and cognitive delays in pediatric patients. This study calls for further research into genetic contributions to asthma, diverse presentations of GERD, prevention of viral illnesses, alternative treatments minimizing steroid use, and an understanding of the impact of chronic respiratory distress on cognitive and language development in children. Thorough workups and interdisciplinary approaches are essential for effective diagnosis and management.
PubMed: 38414706
DOI: 10.7759/cureus.53109 -
International Journal of Genomics 2024Wiskott-Aldrich syndrome (WAS) is a rare X-linked recessive genetic disease characterized by clinical symptoms such as eczema, thrombocytopenia with small platelets,...
Wiskott-Aldrich syndrome (WAS) is a rare X-linked recessive genetic disease characterized by clinical symptoms such as eczema, thrombocytopenia with small platelets, immune deficiency, prone to autoimmune diseases, and malignant tumors. This disease is caused by mutations of the gene encoding WASprotein (WASP). The locus and type of mutations of the gene and the expression quantity of WASP were strongly correlated with the clinical manifestations of patients. We found a novel mutation in the gene (c.931 + 5G > C), which affected splicing to produce three abnormal mRNA, resulting in an abnormally truncated WASP. This mutation led to a reduction but not the elimination of the normal WASP population, resulting in causes X-linked thrombocytopenia (XLT) with mild clinical manifestations. Our findings revealed the pathogenic mechanism of this mutation.
PubMed: 38410787
DOI: 10.1155/2024/2277956