Publications by authors named "John Toubia"

Genomic profiling in chronic-phase chronic myeloid leukemia (CP-CML) patients demonstrated somatic variants in blood cancer-related genes (CGVs) and rearrangements associated with the formation of the Philadelphia-chromosome (Ph-associated rearrangements) at diagnosis, collectively termed additional genetic abnormalities (AGA). AGAs had a negative impact on failure-free survival and molecular response in imatinib-treated patients. We investigated whether treatment with more potent therapies could overcome the negative impact of AGAs at diagnosis.

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Publicly accessible expression data produced by large consortium projects like TCGA and GTEx are increasing in number and size at an unprecedented rate. Their utility cannot be underestimated given the diversity of valuable tools widely used to interrogate these data and the many discoveries of biological and clinical significance already garnered from these datasets. However, there remain undiscovered ways to mine these rich resources and a continuing need to provide researchers with easily accessible and user-friendly applications for complex or bespoke analyses.

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Solid tumours routinely access the blood supply by promoting endothelium-dependent angiogenesis; but tumour vasculature can also be formed by cancer cells themselves via vasculogenic mimicry (VM). Investigation of the gene expression profile during the early stages of VM formation by MDA-MB-231-LM2 breast cancer cells identified the transcriptional regulator inhibitor of DNA binding 1 (ID1) to be elevated ~ 10-fold within the first 2 hours. This role for ID1 in promoting VM was supported by ID1 genetic knockdown or chemical inhibition interrupting VM formation by MDA-MB-231-LM2 (breast) and BxPC-3 (pancreatic) cancer cells.

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Article Synopsis
  • STAT3 gain-of-function disease causes issues like immune system overactivity and growth problems, but long-term treatment with the JAK inhibitor ruxolitinib has shown promise in symptom relief.
  • The study monitored clinical and immune responses of four patients over a year, noting significant changes in T cell populations and the normalization of blood cell profiles, which were previously dysregulated.
  • Ruxolitinib treatment not only managed symptoms but also modified harmful immune cell characteristics and reduced certain auto-reactive T-cell clones, suggesting a potential pathway to better control the disease's impact.
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  • * The standard treatment—surgery and chemotherapy—causes significant side effects and reduces patients' quality of life, highlighting the need for new, less toxic therapies.
  • * Research on plasma-activated media (PAM) shows it may be more effective than traditional chemotherapy, promoting cancer cell death and oxidative stress in HGSOC, paving the way for future clinical applications.
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  • The study investigates the CHEK2 gene, known for its association with breast cancer, to see if it plays a role in pituitary adenomas (PAs) among patients.
  • Researchers analyzed 165 individuals with PAs using genetic sequencing, finding that 3% had rare and potentially harmful CHEK2 variants, indicating a possible link to pituitary tumor development.
  • The findings suggest that CHEK2 variants could be a significant risk factor for PAs, especially since these tumors are common and often don't follow typical family history patterns.
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Circular RNAs (circRNAs), which are increasingly being implicated in a variety of functions in normal and cancerous cells, are formed by back-splicing of precursor mRNAs in the nucleus. circRNAs are predominantly localized in the cytoplasm, indicating that they must be exported from the nucleus. Here we identify a pathway that is specific for the nuclear export of circular RNA.

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Introduction: Germline loss-of-function variants in , encoding peptidylglycine α-amidating monooxygenase (PAM), were recently discovered to be enriched in conditions of pathological pituitary hypersecretion, specifically: somatotrophinoma, corticotrophinoma, and prolactinoma. PAM is the sole enzyme responsible for C-terminal amidation of peptides, and plays a role in the biosynthesis and regulation of multiple hormones, including proopiomelanocortin (POMC).

Methods: We performed exome sequencing of germline and tumour DNA from 29 individuals with functioning pituitary adenomas (12 prolactinomas, 10 thyrotrophinomas, 7 cyclical Cushing's disease).

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While bortezomib has significant benefits in multiple myeloma (MM) therapy, the disease remains incurable due to the invariable development of bortezomib resistance. This emphasises the need for advanced models for preclinical evaluation of new therapeutic approaches for bortezomib-resistant MM. Here, we describe the development of an orthotopic syngeneic bortezomib-resistant MM mouse model based on the most well-characterised syngeneic MM mouse model derived from spontaneous MM-forming C57BL/KaLwRij mice.

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While the majority of circRNAs are formed from infrequent back-splicing of exons from protein coding genes, some can be produced at quite high level and in a regulated manner. We describe the regulation, biogenesis and function of circDOCK1(2-27), a large, abundant circular RNA that is highly regulated during epithelial-mesenchymal transition (EMT) and whose formation depends on the epithelial splicing regulator ESRP1. CircDOCK1(2-27) synthesis in epithelial cells represses cell motility both by diverting transcripts from DOCK1 mRNA production to circRNA formation and by direct inhibition of migration by the circRNA.

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Background: Patients with severe asthma can present with eosinophilic type 2 (T2), neutrophilic, or mixed inflammation that drives airway remodeling and exacerbations and represents a major treatment challenge. The common β (βc) receptor signals for 3 cytokines, GM-CSF, IL-5, and IL-3, which collectively mediate T2 and neutrophilic inflammation.

Objective: To determine the pathogenesis of βc receptor-mediated inflammation and remodeling in severe asthma and to investigate βc antagonism as a therapeutic strategy for mixed granulocytic airway disease.

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The first step of oncogenesis is the acquisition of a repertoire of genetic mutations to initiate and sustain the malignancy. An important example of this initiation phase in acute leukemias is the formation of a potent oncogene by chromosomal translocations between the mixed lineage leukemia (MLL) gene and one of 100 translocation partners, known as the MLL recombinome. Here, we show that circular RNAs (circRNAs)-a family of covalently closed, alternatively spliced RNA molecules-are enriched within the MLL recombinome and can bind DNA, forming circRNA:DNA hybrids (circR loops) at their cognate loci.

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Unlabelled: Leukemia stem cells (LSC) possess distinct self-renewal and arrested differentiation properties that are responsible for disease emergence, therapy failure, and recurrence in acute myeloid leukemia (AML). Despite AML displaying extensive biological and clinical heterogeneity, LSC with high interleukin-3 receptor (IL3R) levels are a constant yet puzzling feature, as this receptor lacks tyrosine kinase activity. Here, we show that the heterodimeric IL3Rα/βc receptor assembles into hexamers and dodecamers through a unique interface in the 3D structure, where high IL3Rα/βc ratios bias hexamer formation.

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Unlabelled: Inhibiting the androgen receptor (AR), a ligand-activated transcription factor, with androgen deprivation therapy is a standard-of-care treatment for metastatic prostate cancer. Paradoxically, activation of AR can also inhibit the growth of prostate cancer in some patients and experimental systems, but the mechanisms underlying this phenomenon are poorly understood. This study exploited a potent synthetic androgen, methyltestosterone (MeT), to investigate AR agonist-induced growth inhibition.

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Transcriptional enhancer elements are responsible for orchestrating the temporal and spatial control over gene expression that is crucial for programming cell identity during development. Here we describe a novel enhancer element that is important for regulating the expression of Prox1 in lymphatic endothelial cells. This evolutionarily conserved enhancer is bound by key lymphatic transcriptional regulators including GATA2, FOXC2, NFATC1 and PROX1.

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Article Synopsis
  • Pregnancy loss and perinatal death deeply affect families, and a study evaluated 'genomic autopsy' along with standard autopsy for 200 affected families, achieving definitive or candidate genetic diagnoses in 105 of them.
  • The findings revealed new types of genetic disorders, with the inheritance patterns showing that 42% of diagnosed cases could lead to risks in future pregnancies.
  • At least 10 families utilized these genetic diagnoses for future pregnancy planning, highlighting the significance of genomic investigations in providing timely information and support for families experiencing pregnancy loss.
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  • * It finds that mutations in complex I genes are mutually exclusive with IDH1 mutations but not with IDH2 mutations, indicating a unique relationship that affects how the cancer cells metabolize nutrients.
  • * The research highlights that IDH1 mutations create a specific weakness in metabolism, making IDH1-mutant cells more sensitive to treatments that target complex I, revealing potential new therapy strategies for AML patients.
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Glioblastoma is the most common and aggressive form of primary brain cancer, with no improvements in the 5-year survival rate of 4.6% over the past three decades. T-cell-based immunotherapies such as immune-checkpoint inhibitors and chimeric antigen receptor T-cell therapy have prolonged the survival of patients with other cancers and have undergone early-phase clinical evaluation in glioblastoma patients.

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The introduction of the proteasome inhibitor bortezomib into treatment regimens for myeloma has led to substantial improvement in patient survival. However, whilst bortezomib elicits initial responses in many myeloma patients, this haematological malignancy remains incurable due to the development of acquired bortezomib resistance. With other patients presenting with disease that is intrinsically bortezomib resistant, it is clear that new therapeutic approaches are desperately required to target bortezomib-resistant myeloma.

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microRNAs (miRNAs) are important modulators of messenger RNA stability and translation, controlling wide gene networks. Albeit generally modest on individual targets, the regulatory effect of miRNAs translates into meaningful pathway modulation through concurrent targeting of regulons with functional convergence. Identification of miRNA-regulons is therefore essential to understand the function of miRNAs and to help realise their therapeutic potential, but it remains challenging due to the large number of false positive target sites predicted per miRNA.

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Translation of eukaryotic mRNAs begins with binding of their m7G cap to eIF4E, followed by recruitment of other translation initiation factor proteins. We describe capCLIP, a novel method to comprehensively capture and quantify the eIF4E (eukaryotic initiation factor 4E) 'cap-ome' and apply it to examine the biological consequences of eIF4E-cap binding in distinct cellular contexts. First, we use capCLIP to identify the eIF4E cap-omes in human cells with/without the mTORC1 (mechanistic target of rapamycin, complex 1) inhibitor rapamycin, there being an emerging consensus that rapamycin inhibits translation of TOP (terminal oligopyrimidine) mRNAs by displacing eIF4E from their caps.

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Background: Organoids are a reliable model used in the study of human brain development and under pathological conditions. However, current methods for brain organoid culture generate tissues that range from 0.5 to 2 mm of size, which need to be constantly agitated to allow proper oxygenation.

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