1,720,975 research outputs found
CONGENITAL ERYTHROCYTOSIS ARE RARE DISORDERS WITH MANY GENES INVOLVED. FUNCTIONAL EVALUATION OF NOVEL PHD2 AND EPOR MUTATIONS.
Get PDFCongenital Erythrocytosis (CE) are rare and heterogeneous clinical entities. They are caused by genetic deregulation of the erythroid production resulting in increased production of red blood cells (RBCs). Primary Congenital Familial Polycythemia (PCFP) is due to erythropoietin receptor (EPOR) mutations and is associated with reduced levels of serum erythropoietin (EPOs). Secondary CE are characterized by high EPOs levels, may be due to mutations of the oxygen-sensing pathway (OSP) genes: von Hippel-Lindau (VHL), hypoxia-inducible factor 2 alpha (HIF2A/EPAS1) and prolyl hydroxylase 2 (EGLN1/PHD2).
Within 106 patients followed in our centre with sporadic not myeloproliferative erythrocytosis we found 9 mutations (8,5%) in the involved genes. Here we report the functional studies of 1 novel PHD2 (c.1045G>A) and of 2 EPOR gene missense mutations (c.1013G>A and c.1022C>T).
To evaluate the HIF transcriptional activity of PHD2 mutation, an in cellulo reporter assay has been performed, while the hydroxylation capacity of PHD2 variants has been tested with an in vitro Hydroxylation test. PHD2 variant does not show a clear loss-of-function of the PHD2 proteins. More sensitive tests could be developed and other PHD2 partners may be tested in this patient.
The activation of EPOR mutated signaling was evaluated with a kinetic assay using transfected K562 cell lines. The EPOR signaling cascade results more active in mutated cells than in the WT cells when stimulated with EPO as shown by higher phosphorylation of STAT5 and ERK. Both mutations impair the C-terminal negative regulatory domain and determine gain-of-function in the EPOR signalling cascade. These are the first missense mutations of EPOR with a functional demonstrated activity that affect the EPOR signaling cascade.
Other candidate genes need to be investigated to completely understand the ethiology of high hematocrit (HCT) level both in congenital and sporadic erythrocytosisLe Eritrocitosi Congenite (CE) sono entità cliniche rare ed eterogenee. Esse sono causate dalla deregolazione genetica della produzione eritroide con conseguente incremento della produzione delle cellule rosse del sangue (RBCs). La Policitemia Congenita Primaria Familiare (PCFP) è dovuta a mutazioni del recettore dell’eritropoietina (EPOR) ed è associata a bassi livelli di eritropoietina sierica (EPOs). Le CE secondarie, invece, sono caratterizzate da elevati valori di EPOs dovuti ad alterazioni dei geni dell’ Oxygen Sensing Pathway (OSP): von Hippel- Lindau (VHL), hypoxia-inducible factor 2 alpha (HIF2A/EPAS1) e prolyl hydroxylase 2 (EGLN1/PHD2).
Nel nostro centro sono stati seguiti 106 pazienti con eritrocitosi sporadica non mieloproliferativa nei quali abbiamo trovato 9 mutazioni (8,5%) nei geni candidati.
Al fine di valutare l’attività trascrizionale di HIF in presenza di PHD2 mutato è stato messo a punto un reporter assay in cellulo, mentre l’attività di idrossilazione di PHD2 è stata testata con un hydroxylation test in vitro. Non è stata riscontrata una chiara loss-of-function per la variante di PHD2 nonostante il link mutazione-malattia. Pertanto si necessita lo sviluppo di test più sensibili oltre allo studio di altri geni partner.
La cascata del segnale di EPOR mutato è stata studiata effettuando una cinetica di stimolazione su cellule K562 trasfettate. In seguito a stimolazione con EPO il signaling di EPOR è risultato più attivo in condizioni mutate rispetto al wild type rilevando alti livelli di fosforilazione di STAT5 e ERK. Entrambe le mutazioni compromettono il dominio regolatore negativo C-terminale di EPOR causando una gain-of-function del recettore.
Queste sono le prime mutazioni missenso in cui in cui è stata rilevata un’iperattivazione dei componenti della cascata del segnale di EPOR.
Altri geni candidati devono essere investigati per comprendere completamente l’eziologia degli alti valori di ematocrito (HTC) sia nei casi di eritrocisi sporadiche sia in quelle congenite
Venous thrombosis in von Willebrand disease as observed in one centre and as reported in the literature.
No full textThe aim of this article was to investigate the prevalence of venous thrombosis in patients with von Willebrand disease. Personal records on 486 patients were reevaluated together with a time unlimited PubMed search. The venous thrombotic event had to be proven by objective means. Only cases of congenital von Willebrand disease were taken into consideration and all types of the diseases were included. No case of venous thrombosis was reported in our cohort of patients. On the contrary, 33 patients with proven venous thrombosis were gathered from the literature (17 cases of deep venous thrombosis with or without pulmonary embolism; isolated pulmonary embolism was seen in seven instances, superficial veins or portal system thrombosis was present in the remaining cases). Associated risk factors, mainly replacement therapy, were present in 26 cases. Therapeutic approach was usually based on heparin and Coumadin. Overall results were fair or good, as no fatalities occurred
Myocardial Infarctions and Other Acute Coronary Syndromes in Rare Congenital Bleeding Disorders: A Critical Analysis of All Reported Cases.
No full textIschemic strokes in congenital bleeding disorders: comparison with myocardial infarction and other acute coronary syndromes
No full textSpatial-transcriptomic profiling: a new lens for understanding myelofibrosis pathophysiology
No full textMyelofibrosis (MF) is a complex myeloproliferative neoplasm characterized by abnormal hematopoietic stem cell proliferation and subsequent bone marrow (BM) fibrosis. First documented in the late 19th century, MF has since been extensively studied to unravel its pathophysiology, clinical phenotypes, and therapeutic interventions. MF can be classified into primary and secondary forms, both driven by mutations in genes such as JAK2, CALR, and MPL, which activate the JAK-STAT signaling pathway. These driver mutations are frequently accompanied by additional non-driver mutations in genes like TET2, SRSF2, and TP53, contributing to disease complexity. The BM microenvironment, consisting of stromal cells, extracellular matrix, and cytokines such as TGF-β and TNF-α, plays a critical role in fibrosis and aberrant hematopoiesis. Clinically, MF manifests with symptoms ranging from anemia, splenomegaly, and fatigue to severe complications such as leukemic transformation. Splenomegaly, caused by extramedullary hematopoiesis, leads to abdominal discomfort and early satiety. Current therapeutic strategies include JAK inhibitors like Ruxolitinib, which target the JAK-STAT pathway, alongside supportive treatments such as blood transfusions, erythropoiesis-stimulating agents and developing combinatorial approaches. Allogeneic hematopoietic stem cell transplantation remains the only curative option, though it is limited to younger, high-risk patients. Recently approved JAK inhibitors, including Fedratinib, Pacritinib, and Momelotinib, have expanded the therapeutic landscape. Spatially Resolved Transcriptomics (SRT) has revolutionized the study of gene expression within the spatial context of tissues, providing unprecedented insights into cellular heterogeneity, spatial gene regulation, and microenvironmental interactions, including stromal-hematopoietic dynamics. SRT enables high-resolution mapping of gene expression in the BM and spleen, revealing molecular signatures, spatial heterogeneity, and pathological niches that drive disease progression. These technologies elucidate the role of the spleen in MF, highlighting its transformation into a site of abnormal hematopoietic activity, fibrotic changes, and immune cell infiltration, functioning as a “tumor surrogate.” By profiling diverse cell populations and molecular alterations within the BM and spleen, SRT facilitates a deeper understanding of MF pathophysiology, helping identify novel therapeutic targets and biomarkers. Ultimately, integrating spatial transcriptomics into MF research promises to enhance diagnostic precision and therapeutic innovation, addressing the multifaceted challenges of this disease
Acute myeloid leukemia: from NGS, through scRNA-seq, to CAR-T. dissect cancer heterogeneity and tailor the treatment
Get PDFAbstract Acute myeloid leukemia (AML) is a malignant blood cancer with marked cellular heterogeneity due to altered maturation and differentiation of myeloid blasts, the possible causes of which are transcriptional or epigenetic alterations, impaired apoptosis, and excessive cell proliferation. This neoplasm has a high rate of resistance to anticancer therapies and thus a high risk of relapse and mortality because of both the biological diversity of the patient and intratumoral heterogeneity due to the acquisition of new somatic changes. For more than 40 years, the old gold standard “one size fits all” treatment approach included intensive chemotherapy treatment with anthracyclines and cytarabine. The manuscript first traces the evolution of the understanding of the pathology from the 1970s to the present. The enormous strides made in its categorization prove to be crucial for risk stratification, enabling an increasingly personalized diagnosis and treatment approach. Subsequently, we highlight how, over the past 15 years, technological advances enabling single cell RNA sequencing and T-cell modification based on the genomic tools are affecting the classification and treatment of AML. At the dawn of the new millennium, the advent of high-throughput next-generation sequencing technologies has enabled the profiling of patients evidencing different facets of the same disease, stratifying risk, and identifying new possible therapeutic targets that have subsequently been validated. Currently, the possibility of investigating tumor heterogeneity at the single cell level, profiling the tumor at the time of diagnosis or after treatments exist. This would allow the identification of underrepresented cellular subclones or clones resistant to therapeutic approaches and thus responsible for post-treatment relapse that would otherwise be difficult to detect with bulk investigations on the tumor biopsy. Single-cell investigation will then allow even greater personalization of therapy to the genetic and transcriptional profile of the tumor, saving valuable time and dangerous side effects. The era of personalized medicine will take a huge step forward through the disclosure of each individual piece of the complex puzzle that is cancer pathology, to implement a “tailored” therapeutic approach based also on engineered CAR-T cells
Associated risk factors and arterial occlusions in patients with von Willebrand disease: Analysis of the literature and report of two cases
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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