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1.
J Assoc Genet Technol ; 50(1): 14-18, 2024.
Article in English | MEDLINE | ID: mdl-38447205

ABSTRACT

OBJECTIVES: Penile cancer, while relatively rare compared to other male malignancies, has seen an increased global incidence, with 36,068 new cases reported in 2020. This condition primarily affects regions with low human development indexes, notably India, China and Brazil. The mainstay of treatment is often partial or total penectomy, which has a profound impact on patients' emotional and social lives. Due to limited options for early diagnosis, non-surgical treatments, restricted healthcare funding and the negative consequences of mutilating surgeries, penile cancer is often considered a neglected disease. Penile cancer exhibits various histological types, but penile squamous cell carcinoma (SCC) is the most prevalent, accounting for 95% of cases worldwide. Multiple risk factors are associated with this condition, largely tied to lifestyle behaviors, such as promiscuous sexual behavior, zoophilia, poor hygiene, phototherapy, smoking and obesity. Human papillomavirus (HPV) infection is a significant etiological factor, particularly in squamous cell carcinomas. The prevalence of HPV in penile neoplasia varies widely, and its association with mortality remains uncertain.

2.
Stud Health Technol Inform ; 310: 1436-1437, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38269684

ABSTRACT

We propose an automated approach to rank the most salient variables related to a certain clinical phenomenon from scientific literature. Our solution is an automated approach to improve the efficiency of the collection of different health-related measures from a population, and to accelerate the discovery of novel associations and dependencies between health-related concepts.

3.
Nat Metab ; 5(12): 2111-2130, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38097808

ABSTRACT

Fibrogenesis is part of a normal protective response to tissue injury that can become irreversible and progressive, leading to fatal diseases. Senescent cells are a main driver of fibrotic diseases through their secretome, known as senescence-associated secretory phenotype (SASP). Here, we report that cellular senescence, and multiple types of fibrotic diseases in mice and humans are characterized by the accumulation of iron. We show that vascular and hemolytic injuries are efficient in triggering iron accumulation, which in turn can cause senescence and promote fibrosis. Notably, we find that senescent cells persistently accumulate iron, even when the surge of extracellular iron has subdued. Indeed, under normal conditions of extracellular iron, cells exposed to different types of senescence-inducing insults accumulate abundant ferritin-bound iron, mostly within lysosomes, and present high levels of labile iron, which fuels the generation of reactive oxygen species and the SASP. Finally, we demonstrate that detection of iron by magnetic resonance imaging might allow non-invasive assessment of fibrotic burden in the kidneys of mice and in patients with renal fibrosis. Our findings suggest that iron accumulation plays a central role in senescence and fibrosis, even when the initiating events may be independent of iron, and identify iron metabolism as a potential therapeutic target for senescence-associated diseases.


Subject(s)
Cellular Senescence , Senescence-Associated Secretory Phenotype , Humans , Iron , Kidney , Fibrosis
4.
J Assoc Genet Technol ; 49(3): 121-126, 2023.
Article in English | MEDLINE | ID: mdl-37665724

ABSTRACT

OBJECTIVES: The ribosomal protein S14 (RPS14) gene located at 5q33 codes for a protein involved in ribosomal biogenesis. The RPS14 gene has a length of 5.9 kb of DNA comprising 5 exons and 4 introns. It is possible that RPS14 is involved in the formation of pre-RNA 18s, an intermediate RNA that serves for the formation of the 40S small subunit of the ribosome. RPS14 haploinsufficiency (HI) produces alterations in intermediate RNA levels (pre-RNA 30S/18SE/18S), which are found in del(5q) MDS. In addition, RPS14 haploinsufficiency results in the formation of the MDM2 (double minute mouse E3 ubiquitin ligase)-RP (ribosomal protein) complex that prevents the MDM2-p53 interaction, generating an accumulation of p53 levels. This accumulation produces cell cycle arrest, impaired DNA repair, senescence, and apoptosis. RPS14 haploinsufficiency has been seen in MDS. Altered expression levels of RPS14 have also been reported in glioma, colorectal cancer, hepatocellular carcinoma, breast cancer, renal cell carcinoma, and primary myelofibrosis.

5.
J Assoc Genet Technol ; 49(3): 127-132, 2023.
Article in English | MEDLINE | ID: mdl-37665723

ABSTRACT

OBJECTIVES: B-cell acute lymphoblastic leukemia (B-ALL) is one of the most common leukemias affecting the pediatric population. It represents ~25% of cancer diagnoses among children. Specific genetic changes predict the prognosis in B-ALL with recurrent genetic changes. Here we present a case report of a 20-year-old male with B-ALL. The patient presented with acute onset worsening upper extremity pain with pallor, weight loss, dizziness, fatigue, and abnormal complete blood count (CBC). Conventional cytogenetics showed a karyotype of 46,XY,add(9)(q13),i(9)(q10)[19]. DNA FISH analysis performed on the bone marrow showed hemizygous deletion of the 9p21(CDKN2A) in 15.5% of the nuclei examined. The presence of an isochromosome 9q [i(9)(q10) is a rare event in pediatric B-ALL. An isochromosome 9q occurs in 0.6% of the patients studied in the literature. The significance of this abnormality in pediatric B-ALL is not clear. Profiling cases like this to understand the molecular mechanisms of rare chromosomal abnormalities and rare mutations in children with B-ALL could help us to better treat them.

6.
J Assoc Genet Technol ; 49(2): 88-92, 2023.
Article in English | MEDLINE | ID: mdl-37269293

ABSTRACT

OBJECTIVES: B-cell acute lymphoblastic leukemia (B-ALL) can afflict both adult and pediatric patients and is characterized by a build-up of B lymphoblasts. Here we present a case of a 25-year-old male patient with a history of B-ALL. Ninety percent of the bone marrow revealed pancytopenia with sheets of B lymphoblasts consistent with the diagnosis of B-ALL for acute pre-B lymphoblastic leukemia. The immunophenotype also presented predominant immature precursor B lymphoid cells positive for CD19, CD10, CD34, CD58, CD38, CD9, and TdT. Chromosome analysis of the bone marrow showed a complex karyotype described as 45~47,XY,i(8)(q10),der(10)add(10)(p11.1)add(10)(q23),-20,+1~2mar[cp3]/46,XY[36]. While IGH rearrangements were cryptic cytogenetically, DNA FISH analysis showed evidence of the IGH (14q32.2) gene rearrangement in 96.5% of the nuclei examined. These results were described as nuc ish(IGHx2)(5'IGH sep 3'IGHx1)[187/200],(5'IGH,3'IGH)x1~4(5'IGH con 3'IGHx0~2) [6/200]. The remaining probes were normal. Further studies using the MYC/IGH DC, DF probe from Abbott showed a gain of IGH signal in 7.5% of the nuclei examined: nuc ish(MYCx2,IGHx3)[15/200]. Metaphase FISH also showed that what appeared to be an isochromosome 8q was a derivative chromosome 8 defined as add(8)(p11.2) that contained a green IGH signal. In light of these results the karyotype was characterized as 45~47,XY,add(8)(p11.2),der(10)add(10)(p11.1)add(10)(q23),-20,+1~2mar[cp3].ish add(8) (p11.2) IgH+. IgH abnormalities are rare in B-ALL and are usually associated with a poor prognosis. However, at the present time our patient presented no evidence of persistent or residual disease and a cytogenetic response to the present therapy.

7.
J Assoc Genet Technol ; 49(2): 79-87, 2023.
Article in English | MEDLINE | ID: mdl-37269317

ABSTRACT

OBJECTIVES: We present a case study of a 73-year-old female with a history of pancytopenia. The bone marrow core biopsy was suggestive of a myelodysplastic syndrome, unspecified (MDS-U). Chromosomal analysis of the bone marrow revealed an abnormal karyotype including gain of chromosomes 1, 4, 6, 8, 9, 19, and 20 in addition to loss of chromosomes 11, 13, 15, 16, 17, and 22. Also, additional material of unknown origin was found on 3q, 5p, 9p, 11p, 13p, 14p, and 15p; there were two copies of 19p, a deletion of 8q, and numerous unidentified rings and markers were present. This was characterized as: 75~77,XXX,+1,der(1;6)(p10;p10),add(3)(q27),+4,add(5)(p15.1),+6,+8,del(8)(q24.1),+add(9)(p24),-11,add (11) (p13),-13,add(13)(p10),add(14)(p11.2),-15,add(15)(p11.2), -16,-17,+19,add(19)(p13.3)x2,+20,-22, +0~4r,+4~10mar[cp11]/46,XX[8]. The cytogenetic analysis correlates with the concurrent FISH study which was positive for additional signals of EVI1(3q26.2), TAS2R1 (5p15.31), EGR1 (5q31.2), RELN (7q22), TES (7q31) RUNX1T1 (8q21.3), ABL1 (9q34), KMT2A (11q23), PML (15q24.1), CBFB (16q22), RARA (17q21), PTPRT (20q12), MYBL2 (20q13.12), RUNX1 (21q22.12) and BCR (22q11.2). Hyperdiploid karyotypes within the context of complex structural abnormalities are rare events usually associated with a poor prognosis in MDS.

8.
J Assoc Genet Technol ; 49(1): 11-20, 2023.
Article in English | MEDLINE | ID: mdl-36867854

ABSTRACT

OBJECTIVES: The Janus Kinase 2 gene (JAK2) provides instructions for generating a protein that promotes the division and growth, or what is referred to as the proliferation, of cells. This generated protein relays signals in cells in order to promote cell growth, as well as help manage the count of white blood cells, red blood cells, and platelets that are generated within the bone marrow. Mutations and rearrangements of JAK2 are found in 3.5% of B-acute lymphoblastic leukemia (B-ALL) cases and in 18.9% of Down syndrome B-ALL patients, and are associated with a Ph-like ALL and a poor prognosis. However, there have been great challenges in understanding their role in this pathogenesis. In this review, we will discuss the most recent literature and trends associated with JAK2 mutations in patients with B-ALL.

9.
Int J Mol Sci ; 23(21)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36361868

ABSTRACT

Pericytes at the blood-brain barrier (BBB) are located between the tight endothelial cell layer of the blood vessels and astrocytic endfeet. They contribute to central nervous system (CNS) homeostasis by regulating BBB development and maintenance. Loss of pericytes results in increased numbers of infiltrating immune cells in the CNS in experimental autoimmune encephalomyelitis (EAE), the mouse model for multiple sclerosis (MS). However, little is known about their competence to modulate immune cell activation or function in CNS autoimmunity. To evaluate the capacity of pericytes to directly interact with T cells in an antigen-specific fashion and potentially (re)shape their function, we depleted major histocompatibility complex (MHC) class II from pericytes in a cell type-specific fashion and performed T cell-pericyte cocultures and EAE experiments. We found that pericytes present antigen in vitro to induce T cell activation and proliferation. In an adoptive transfer EAE experiment, pericyte-specific MHC II KO resulted in locally enhanced T cell infiltration in the CNS; even though, overall disease course of mice was not affected. Thus, pericytes may serve as non-professional antigen-presenting cells affecting states of T cell activation, thereby locally shaping lesion formation in CNS inflammation but without modulating disease severity.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Mice , Animals , Encephalomyelitis, Autoimmune, Experimental/pathology , Pericytes/pathology , T-Lymphocytes , Central Nervous System/pathology , Blood-Brain Barrier/pathology , Antigens , Histocompatibility Antigens Class II , Mice, Inbred C57BL
10.
Elife ; 112022 10 05.
Article in English | MEDLINE | ID: mdl-36197007

ABSTRACT

The blood-brain barrier (BBB) limits the entry of leukocytes and potentially harmful substances from the circulation into the central nervous system (CNS). While BBB defects are a hallmark of many neurological disorders, the cellular heterogeneity at the neurovascular interface, and the mechanisms governing neuroinflammation are not fully understood.Through single-cell RNA sequencing of non-neuronal cell populations of the murine cerebral cortex during development, adulthood, ageing, and neuroinflammation, we identify reactive endothelial venules, a compartment of specialized postcapillary endothelial cells that are characterized by consistent expression of cell adhesion molecules, preferential leukocyte transmigration, association with perivascular macrophage populations, and endothelial activation initiating CNS immune responses. Our results provide novel insights into the heterogeneity of the cerebral vasculature and a useful resource for the molecular alterations associated with neuroinflammation and ageing.


Subject(s)
Endothelial Cells , Endothelium, Vascular , Animals , Blood-Brain Barrier/metabolism , Brain/metabolism , Cell Adhesion Molecules/metabolism , Endothelial Cells/metabolism , Endothelium, Vascular/metabolism , Mice , Transcriptome
11.
J Assoc Genet Technol ; 48(3): 107-109, 2022.
Article in English | MEDLINE | ID: mdl-36070230

ABSTRACT

OBJECTIVES: Acute myeloid leukemia (AML) is a heterogeneous disease, characterized by clonal expansion of undifferentiated myeloid precursors, leading to alterations in hematopoiesis and bone marrow failure. Characteristic chromosomal abnormalities in AML are translocations t(8;21), inv(16), t(15;17), t(9;22), as well as mutations of genes that regulate proliferation and survival (FLT 3, PTPN 11, ETV 6/PDGFB), or genes responsible for differentiation and apoptosis (RUNX-1/RUNX1T1, PML/RARA, KMT2A, CEBPA and CBFB). Amplification of RUNX1 is a rare event in AML. Herein we described a 60-year-old patient that was admitted to the hospital due to a clinical picture of symptoms of acute anemia, thrombocytopenia, leukocytosis, and profuse nasal bleeding, hepatomegaly, splenomegaly, and gallstones. The blood cell count indicated the presence of 72% blasts. The bone marrow also showed 97% of blasts of myeloid lineage. The flow cytometry study also showed findings compatible with AML (MPOneg/+, CD34+, CD19neg /+d, CD117+, CD38neg /+, HLA-DR ++, CD13neg /+, CD33neg, CD15neg, D56neg, CD123+, CD7neg, CD11bneg, CD64neg, CD41aneg, which represented 68% of the pathological cellularity). Chromosome analysis showed additional copies of an isochromosome 21q. FISH studies revealed five copies of RUNX1. Amplification of RUNX1 is a rare event in AML with only a few cases reported in the literature (mainly therapy related AML) and it is usually associated with poor prognosis.

12.
Circ Res ; 131(4): 308-327, 2022 08 05.
Article in English | MEDLINE | ID: mdl-35862101

ABSTRACT

BACKGROUND: Pericytes and vascular smooth muscle cells, collectively known as mural cells, are recruited through PDGFB (platelet-derived growth factor B)-PDGFRB (platelet-derived growth factor receptor beta) signaling. MCs are essential for vascular integrity, and their loss has been associated with numerous diseases. Most of this knowledge is based on studies in which MCs are insufficiently recruited or fully absent upon inducible ablation. In contrast, little is known about the physiological consequences that result from impairment of specific MC functions. Here, we characterize the role of the transcription factor SRF (serum response factor) in MCs and study its function in developmental and pathological contexts. METHODS: We generated a mouse model of MC-specific inducible Srf gene deletion and studied its consequences during retinal angiogenesis using RNA-sequencing, immunohistology, in vivo live imaging, and in vitro techniques. RESULTS: By postnatal day 6, pericytes lacking SRF were morphologically abnormal and failed to properly comigrate with angiogenic sprouts. As a consequence, pericyte-deficient vessels at the retinal sprouting front became dilated and leaky. By postnatal day 12, also the vascular smooth muscle cells had lost SRF, which coincided with the formation of pathological arteriovenous shunts. Mechanistically, we show that PDGFB-dependent SRF activation is mediated via MRTF (myocardin-related transcription factor) cofactors. We further show that MRTF-SRF signaling promotes pathological pericyte activation during ischemic retinopathy. RNA-sequencing, immunohistology, in vivo live imaging, and in vitro experiments demonstrated that SRF regulates expression of contractile SMC proteins essential to maintain the vascular tone. CONCLUSIONS: SRF is crucial for distinct functions in pericytes and vascular smooth muscle cells. SRF directs pericyte migration downstream of PDGFRB signaling and mediates pathological pericyte activation during ischemic retinopathy. In vascular smooth muscle cells, SRF is essential for expression of the contractile machinery, and its deletion triggers formation of arteriovenous shunts. These essential roles in physiological and pathological contexts provide a rationale for novel therapeutic approaches through targeting SRF activity in MCs.


Subject(s)
Pericytes , Retinal Diseases , Animals , Mice , Pericytes/metabolism , Proto-Oncogene Proteins c-sis/metabolism , RNA/metabolism , Receptor, Platelet-Derived Growth Factor beta/genetics , Receptor, Platelet-Derived Growth Factor beta/metabolism , Retinal Diseases/metabolism , Serum Response Factor/genetics , Serum Response Factor/metabolism
13.
J Assoc Genet Technol ; 48(1): 17-23, 2022.
Article in English | MEDLINE | ID: mdl-35247255

ABSTRACT

OBJECTIVES: Acute myeloid leukemia (AML) presents as a heterogeneous blood cancer characterized by the proliferation of immature myeloid cells. We present the case of an 18-year-old female with AML whose symptoms include marked leukocytosis, anemia, as well as thrombocytopenia with spontaneous cerebellar and intracerebral bleeds. The bone marrow biopsy is hypercellular and is expunged by sheets of blast cells with dispersed chromatin, prominent nucleoli, highly irregular nuclei, and moderate cytoplasm. Chromosome analysis reveals an abnormal karyotype with a derivative trisomy 8 and a derivative chromosome 16. The karyotype is described as 47,XX,+der(8)add(8)(q24.3),der(16) inv(16)(p13.1q22)del(16)(q22)[21]/46,XX[1]. DNA FISH analysis reveals abnormalities for RUNX1T1 (8q21.3) and CBFB (16q22) genes. These findings align with that of conventional cytogenetics. The National Comprehensive Cancer Network guidelines for AML state that CBFB gene rearrangements indicate that the patient falls under the favorable risk category. However, AML with core binding factor molecular aberrations is a heterogeneous group and thus the interaction with further cytogenetic abnormalities may result in further pathogenesis. Clinical correlation was suggested.

14.
J Assoc Genet Technol ; 48(1): 24-31, 2022.
Article in English | MEDLINE | ID: mdl-35247256

ABSTRACT

OBJECTIVES: Glioblastoma Multiforme (GBM) is the most malignant and frequently occurring primary brain tumor out of the different types of primary astrocytomas. It presents with an extremely poor prognosis, with a median survival of 14 to 15 months from the diagnosis. Herein, we present an 83-year-old female patient with a right frontal brain mass. A craniotomy for the frontal brain mass was performed, which revealed a tumor with high-grade glioma, necrosis, atypia, and vascular proliferation. The patient was subsequently diagnosed with Glioblastoma Multiforme Grade IV (GBM). Molecular cytogenetic studies showed an amplification of the EGFR gene in 100% nuclei scored. Amplification of EGFR appears in around 40-50% of individuals with Glioblastoma Multiforme Grade IV, leading to high levels of EGFR protein levels that contribute to tumorigenesis. Chromosomal deletions involving 1p36 and 19q13 are characteristic molecular features of solid tumors such as oligodendrocytes and mixed oligoastrocytomas, but in this case there was no evidence of a co-deletion of 1p36/19q13 in this case of glioblastoma.

15.
JBRA Assist Reprod ; 25(3): 473-479, 2021 07 21.
Article in English | MEDLINE | ID: mdl-34286941

ABSTRACT

OBJECTIVE: Lyophilization is potentially more practical and cost-effective alternative for sperm preservation. However, there are no studies that evaluate the ultrastructure of human spermatozoa after lyophilization. Therefore, the aim of our study was to evaluate the ultrasctructure of lyophilized spermatozoa using Transmission Electron Microscopy. METHODS: From a total of 21 donated seminal samples, 30 aliquots were originated and divided into two aliquots so that one could have been submitted to cryopreservation/thaw and the other for lyophilization/rehydration. The liquefied aliquots were homogenized at room temperature. Samples assigned for cryopreservation were placed in straws and samples assigned for lyophilization were placed in the appropriate vials. Cryopreservation samples were placed at -30oC for 30 minutes subsequently for 30 minutes at vapour phase and then plunged into liquid nitrogen. Lately, were warmed in water bath at 37oC for 10 minutes followed by 10 minutes centrifugation. The pellet was resuspended and analysed in a Makler chamber. The semen vials assigned for lyophilization were loaded into a pre-fixed freeze-drying chamber. Following lyophilization, vials were removed from the freeze-drying chamber and kept at 4oC until rehydration. TEM was performed after rehydration and thawing. Sperm samples were fixed, rinsed in buffer, post fixed and dehydration was carried out in escalating concentrations of alcohol solution, acetone and then, embedding in Epon resin. Ultrathin sections were stained and examined in a Transmission Electron Microscope. RESULTS: Analysis of sperm after freezing/thawing using Transmission Electron Microscopy showed lesions to the midpiece, with some mitochondria degeneration and random rupture of plasma membrane. In the head, we identified intact plasma membrane, nucleus and acrosome, as in the flagellum all main structures remained intact including the plasma membrane, the longitudinal columns of dense fibers and the semicircular fibers. Analysis by Transmission Electron Microscopy showed that spermatozoa heads had ruptured plasma membranes, absence of acrosomes, nuclei with heterogeneous and decompressed chromatin. Mitochondria were deteriorated in the midpiece. Longitudinal columns of dense fibers were absent in the flagellum. Axonemes, in cross-sections, were disrupted with disorganized structures. CONCLUSIONS: To our knowledge, our study demonstrated, for the first time, the structure of the human spermatozoa after lyophilization using Transmission Electron Microscopy. The use of a fixed lyophilization protocol with media containing cryoprotectants might explain the damage to the structures. More studies are necessary to improve the results of sperm lyophilization. In the future, the use of lyophilization of spermatozoa might reduce the costs of fertility preservation, since there will be no need for storage space and transportation is simpler.


Subject(s)
Semen Preservation , Spermatozoa , Acrosome , Cryopreservation , Humans , Male , Semen , Sperm Motility
16.
J Assoc Genet Technol ; 47(2): 60-68, 2021.
Article in English | MEDLINE | ID: mdl-34140438

ABSTRACT

OBJECTIVES: The ASXL1 (additional sex combs like 1) gene on 20q11 codifies the ASXL1 protein that belongs to protein complexes that play a role in gene expression and epigenetic regulation. ASXL1 is located near the DNMT3B gene and is part of a family of three genes (ASXL1, ASXL2, ASXL3) that are homologues to the Drosophila Asx gene. The ASXL1 gene contains a total of 14 exons and is expressed in the vast majority of hematopoietic cell types. While the specific job of ASXL1 in normal hematopoiesis and the involvement of mutated ASXL1 to the progression of hematopoietic malignancies have not yet been fully set forth, current data studies propose that ASXL1 is characterized as a tumor suppressor gene. Mutations in the ASXL1 gene are observed in myeloid malignancies usually associated with aggressiveness and poor clinical results and were reported first in the year 2009 in myelodysplastic syndromes (MDS). Nevertheless, ASXL1 gene mutations are also found in acute myeloid leukemia (AML) with normal karyotype as well as AML with myelodysplasia-related changes and AML with non-characteristic cytogenetic findings. Herein we examine the involvement of the ASXL1 gene in AML to address the importance of these ASXL1 mutations in the prognostic evaluation of AML.

17.
Circulation ; 142(7): 688-704, 2020 08 18.
Article in English | MEDLINE | ID: mdl-32466671

ABSTRACT

BACKGROUND: Pericytes regulate vessel stabilization and function, and their loss is associated with diseases such as diabetic retinopathy or cancer. Despite their physiological importance, pericyte function and molecular regulation during angiogenesis remain poorly understood. METHODS: To decipher the transcriptomic programs of pericytes during angiogenesis, we crossed Pdgfrb(BAC)-CreERT2 mice into RiboTagflox/flox mice. Pericyte morphological changes were assessed in mural cell-specific R26-mTmG reporter mice, in which low doses of tamoxifen allowed labeling of single-cell pericytes at high resolution. To study the role of phosphoinositide 3-kinase (PI3K) signaling in pericyte biology during angiogenesis, we used genetic mouse models that allow selective inactivation of PI3Kα and PI3Kß isoforms and their negative regulator phosphate and tensin homolog deleted on chromosome 10 (PTEN) in mural cells. RESULTS: At the onset of angiogenesis, pericytes exhibit molecular traits of cell proliferation and activated PI3K signaling, whereas during vascular remodeling, pericytes upregulate genes involved in mature pericyte cell function, together with a remarkable decrease in PI3K signaling. Immature pericytes showed stellate shape and high proliferation, and mature pericytes were quiescent and elongated. Unexpectedly, we demonstrate that PI3Kß, but not PI3Kα, regulates pericyte proliferation and maturation during vessel formation. Genetic PI3Kß inactivation in pericytes triggered early pericyte maturation. Conversely, unleashing PI3K signaling by means of PTEN deletion delayed pericyte maturation. Pericyte maturation was necessary to undergo vessel remodeling during angiogenesis. CONCLUSIONS: Our results identify new molecular and morphological traits associated with pericyte maturation and uncover PI3Kß activity as a checkpoint to ensure appropriate vessel formation. In turn, our results may open new therapeutic opportunities to regulate angiogenesis in pathological processes through the manipulation of pericyte PI3Kß activity.


Subject(s)
Neovascularization, Physiologic , Pericytes/enzymology , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , Vascular Remodeling , Animals , Mice , Mice, Transgenic , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Phosphatidylinositol 3-Kinases/genetics
18.
Nat Commun ; 10(1): 2817, 2019 06 27.
Article in English | MEDLINE | ID: mdl-31249304

ABSTRACT

Sufficient vascular supply is indispensable for brain development and function, whereas dysfunctional blood vessels are associated with human diseases such as vascular malformations, stroke or neurodegeneration. Pericytes are capillary-associated mesenchymal cells that limit vascular permeability and protect the brain by preserving blood-brain barrier integrity. Loss of pericytes has been linked to neurodegenerative changes in genetically modified mice. Here, we report that postnatal inactivation of the Rbpj gene, encoding the transcription factor RBPJ, leads to alteration of cell identity markers in brain pericytes, increases local TGFß signalling, and triggers profound changes in endothelial behaviour. These changes, which are not mimicked by pericyte ablation, imperil vascular stability and induce the acquisition of pathological landmarks associated with cerebral cavernous malformations. In adult mice, loss of Rbpj results in bigger stroke lesions upon ischemic insult. We propose that brain pericytes can acquire deleterious properties that actively enhance vascular lesion formation and promote pathogenic processes.


Subject(s)
Brain/metabolism , Hemangioma, Cavernous, Central Nervous System/metabolism , Immunoglobulin J Recombination Signal Sequence-Binding Protein/deficiency , Pericytes/metabolism , Animals , Blood-Brain Barrier/metabolism , Brain/cytology , Disease Progression , Female , Hemangioma, Cavernous, Central Nervous System/genetics , Hemangioma, Cavernous, Central Nervous System/pathology , Humans , Immunoglobulin J Recombination Signal Sequence-Binding Protein/genetics , Male , Mice, Knockout
19.
Nat Commun ; 9(1): 4860, 2018 11 19.
Article in English | MEDLINE | ID: mdl-30451830

ABSTRACT

Canonical Wnt signaling is crucial for vascularization of the central nervous system and blood-brain barrier (BBB) formation. BBB formation and modulation are not only important for development, but also relevant for vascular and neurodegenerative diseases. However, there is little understanding of how Wnt signaling contributes to brain angiogenesis and BBB formation. Here we show, using high resolution in vivo imaging and temporal and spatial manipulation of Wnt signaling, different requirements for Wnt signaling during brain angiogenesis and BBB formation. In the absence of Wnt signaling, premature Sphingosine-1-phosphate receptor (S1pr) signaling reduces VE-cadherin and Esama at cell-cell junctions. We suggest that Wnt signaling suppresses S1pr signaling during angiogenesis to enable the dynamic junction formation during anastomosis, whereas later S1pr signaling regulates BBB maturation and VE-cadherin stabilization. Our data provides a link between brain angiogenesis and BBB formation and identifies Wnt signaling as coordinator of the timing and as regulator of anastomosis.


Subject(s)
Antigens, CD/genetics , Brain/metabolism , Cadherins/genetics , Neovascularization, Physiologic/genetics , Receptors, Lysosphingolipid/genetics , Wnt Signaling Pathway , Zebrafish Proteins/genetics , Zebrafish/genetics , beta Catenin/genetics , Animals , Animals, Genetically Modified , Antigens, CD/metabolism , Blood-Brain Barrier/growth & development , Blood-Brain Barrier/metabolism , Brain/blood supply , Brain/growth & development , Cadherins/metabolism , Capillaries/growth & development , Capillaries/metabolism , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Cerebrovascular Circulation/genetics , Embryo, Nonmammalian , Gene Expression Regulation, Developmental , Genes, Reporter , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Receptors, Lysosphingolipid/metabolism , Zebrafish/growth & development , Zebrafish/metabolism , Zebrafish Proteins/metabolism , beta Catenin/metabolism , Red Fluorescent Protein
20.
JBRA Assist Reprod ; 22(4): 352-354, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-30264947

ABSTRACT

OBJECTIVE: To evaluate COS and oocyte retrieval results in ART treatment cycles initiated at any stage of the menstrual cycle (random start) in cancer patients, who could not postpone the onset of cancer treatment. METHODS: Prospective observational study of 26 women with cancer, with an indication to start cancer treatment within the next 20 days and wishing to preserve their fertility. Ovarian stimulation started immediately with FSH followed by GnRH antagonist for pituitary suppression and GnRH agonist for oocyte maturation. Treatment started from day 1 to day 14 of the menstrual cycle was considered to be in the follicular phase, and that started from day 15 to day 28 was considered to be in the luteal phase. Oocyte retrieval was performed 34 h after GnRH agonist administration. After identification and maturity classification, metaphase II oocytes were cryopreserved using vitrification. RESULTS: A total of 13 women had breast cancer, 4 ovarian cancer, 3 Central Nervous System cancer, 3 endometrial cancer, 2 cervical cancer and one bowel cancer. Thirteen patients started treatment during follicular phase and 13 during luteal phase. We found similar results for the duration of treatment, total dose of follicle stimulating hormone, number of ampoules of gonadotropin releasing hormone antagonist, mean number of follicles identified at ultrasound on the day of trigger and retrieval, number of aspirated oocytes and Metaphase II oocytes. CONCLUSION: Random-start controlled ovarian stimulation for emergency fertility preservation for minimizing delay in oncologic treatment for cancer patients does not interfere with the number of metaphase II oocytes, and therefore can be routinely used for stimulation followed by cryopreservation.


Subject(s)
Fertility Preservation , Menstrual Cycle , Oocyte Retrieval/methods , Ovulation Induction/methods , Cryopreservation , Female , Humans , Neoplasms/complications , Oocytes/cytology , Oocytes/growth & development , Time Factors
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