Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
2.
Nat Cell Biol ; 25(3): 493-507, 2023 03.
Article in English | MEDLINE | ID: mdl-36849558

ABSTRACT

How abnormal neurodevelopment relates to the tumour aggressiveness of medulloblastoma (MB), the most common type of embryonal tumour, remains elusive. Here we uncover a neurodevelopmental epigenomic programme that is hijacked to induce MB metastatic dissemination. Unsupervised analyses of integrated publicly available datasets with our newly generated data reveal that SMARCD3 (also known as BAF60C) regulates Disabled 1 (DAB1)-mediated Reelin signalling in Purkinje cell migration and MB metastasis by orchestrating cis-regulatory elements at the DAB1 locus. We further identify that a core set of transcription factors, enhancer of zeste homologue 2 (EZH2) and nuclear factor I X (NFIX), coordinates with the cis-regulatory elements at the SMARCD3 locus to form a chromatin hub to control SMARCD3 expression in the developing cerebellum and in metastatic MB. Increased SMARCD3 expression activates Reelin-DAB1-mediated Src kinase signalling, which results in a MB response to Src inhibition. These data deepen our understanding of how neurodevelopmental programming influences disease progression and provide a potential therapeutic option for patients with MB.


Subject(s)
Cerebellar Neoplasms , Medulloblastoma , Humans , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Medulloblastoma/genetics , Phosphorylation , Epigenomics , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Cell Adhesion Molecules, Neuronal/genetics , Cell Adhesion Molecules, Neuronal/metabolism , Cell Adhesion Molecules, Neuronal/pharmacology , Cerebellar Neoplasms/genetics , Epigenesis, Genetic , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism
3.
Arch Pathol Lab Med ; 146(6): 677-685, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35188563

ABSTRACT

CONTEXT.­: Moderna (mRNA-1272) and Pfizer (BNT162b2) SARS-CoV-2 vaccines demonstrate favorable safety and efficacy profiles, but direct comparison data are lacking. OBJECTIVE.­: To determine the vaccines' side effect profiles and expected antibody responses. These data may help personalize vaccine selection and identify individuals with a suboptimal vaccine response. DESIGN.­: One hundred forty-nine healthy, largely seronegative adults were assigned Moderna (n = 79) or Pfizer (n = 70). Following the second dose, participants completed a survey documenting their side effects. Serum was collected 0 to 4 days prior to dose 2, and 14 ± 4 days, 30 ± 4 days, 90 ± 10 days, and 180 ± 20 days after dose 2. Convalescent serum specimens were collected 32 to 54 days from donors after a polymerase chain reaction-confirmed SARS-CoV-2 infection (n = 20). Anti-spike antibodies were measured using the Roche Diagnostics Elecys Anti-SARS-CoV-2 S assay on a Roche cobas e801 instrument. RESULTS.­: Participants receiving the Moderna vaccine experienced side effects with greater frequency and severity. Both vaccines elicited a robust antibody response, but median signal was higher in Moderna recipients. Symptom severity decreased with age. Antibody response in Pfizer recipients negatively correlated with age. Antibody response decreased after 6 months (84% reduction in Moderna, 79% Pfizer), but values remained greater than for convalescent donors. Antibody response did not correlate with gender or symptom severity. CONCLUSIONS.­: Moderna may be preferred in individuals in need of greater immune stimulation (eg, older individuals), whereas Pfizer may be preferred in those concerned about vaccine reactions. Anti-spike antibody signal varies by vaccine, so specific reference intervals will be needed to identify individuals with a suboptimal response.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adult , Antibodies, Viral , Antibody Formation , BNT162 Vaccine , COVID-19/prevention & control , COVID-19/therapy , COVID-19 Vaccines/adverse effects , Humans , Immunization, Passive , SARS-CoV-2 , COVID-19 Serotherapy
4.
J Neuropathol Exp Neurol ; 79(1): 74-85, 2020 01 01.
Article in English | MEDLINE | ID: mdl-31819973

ABSTRACT

To evaluate a potential relationship between BRAF V600E mutation and PD-L1 expression, we examined the expression of PD-L1 in pediatric high- and low-grade glioma cell lines as well as a cohort of pediatric low-grade glioma patient samples. Half of the tumors in our patient cohort were V600-wildtype and half were V600E mutant. All tumors expressed PD-L1. In most tumors, PD-L1 expression was low (<5%), but in some cases over 50% of cells were positive. Extent of PD-L1 expression and immune cell infiltration was independent of BRAF V600E mutational status. All cell lines evaluated, including a BRAF V600E mutant xenograft, expressed PD-L1. Transient transfection of cell lines with a plasmid expressing mutant BRAF V600E had minimal effect on PD-L1 expression. These findings suggest that the PD-1 pathway is active in subsets of pediatric low-grade glioma as a mechanism of immune evasion independent of BRAF V600E mutational status. Low-grade gliomas that are unresectable and refractory to traditional therapy are associated with significant morbidity and continue to pose a treatment challenge. PD-1 pathway inhibitors may offer an alternative treatment approach. Clinical trials will be critical in determining whether PD-L1 expression indicates likely therapeutic benefit with immune checkpoint inhibitors.


Subject(s)
B7-H1 Antigen/biosynthesis , B7-H1 Antigen/genetics , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Glioma/genetics , Glioma/pathology , Proto-Oncogene Proteins B-raf/genetics , Adolescent , Brain Neoplasms/immunology , Cell Line, Tumor , Child , Child, Preschool , Cohort Studies , Female , Glioma/immunology , Humans , Immunohistochemistry , Male , Microglia/pathology , Mutation/genetics , Plasmids/genetics , Transfection , Xenograft Model Antitumor Assays , Young Adult
SELECTION OF CITATIONS
SEARCH DETAIL