Search results for "Tumor Suppressor Proteins"
showing 10 items of 123 documents
11q Deletion or ALK Activity Curbs DLG2 Expression to Maintain an Undifferentiated State in Neuroblastoma
2020
High-risk 11q deleted neuroblastomas typically display undifferentiated/poorly differentiated morphology. Neuroblastoma is thought to develop from Schwann cell precursors and undifferentiated neural crest (NC) derived cells. It is therefore vital to understand mechanisms involved in the block of differentiation. We identify an important role for oncogenic ALK-ERK1/2-SP1 signaling in maintenance of undifferentiated NC-derived progenitors via repression of DLG2, a tumor suppressor in neuroblastoma. DLG2 is expressed in the ‘bridge signature’ that represents the transcriptional transition state when neural crest cells or Schwann Cell Precursors become chromaffin cells of the adrenal gland. We …
E4BP4/NFIL3 modulates the epigenetically repressed RAS effector RASSF8 function through histone methyltransferases
2018
RAS proteins are major human oncogenes, and most of the studies are focused on enzymatic RAS effectors. Recently, nonenzymatic RAS effectors (RASSF, RAS association domain family) have garnered special attention because of their tumor-suppressive properties in contrast to the oncogenic potential of the classical enzymatic RAS effectors. Whereas most members of RASSF family are deregulated by promoter hypermethylation, RASSF8 promoter remains unmethylated in many cancers but the mechanism(s) of its down-regulation remains unknown. Here, we unveil E4BP4 as a critical transcriptional modulator repressing RASSF8 expression through histone methyltransferases, G9a and SUV39H1. In line with these …
Structural Basis of the High Affinity Interaction between the Alphavirus Nonstructural Protein-3 (nsP3) and the SH3 Domain of Amphiphysin-2
2016
We show that a peptide from Chikungunya virus nsP3 protein spanning residues 1728–1744 binds the amphiphysin-2 (BIN1) Src homology-3 (SH3) domain with an unusually high affinity (Kd 24 nM). Our NMR solution complex structure together with isothermal titration calorimetry data on several related viral and cellular peptide ligands reveal that this exceptional affinity originates from interactions between multiple basic residues in the target peptide and the extensive negatively charged binding surface of amphiphysin-2 SH3. Remarkably, these arginines show no fixed conformation in the complex structure, indicating that a transient or fluctuating polyelectrostatic interaction accounts for this …
A recurrent TP63 mutation causing EEC3 and Rapp–Hodgkin syndromes
2016
The ectrodactyly, ectodermal dysplasia, and cleft lip/palate syndrome 3 (EEC3; OMIM #604292), the Rapp-Hodgkin syndrome (RHS), and various other syndromes are caused by mutations in the TP63 gene, which encodes a p53-like transcription factor. Here, we report on a woman aged 37 years and her daughter aged 3 years with the previously reported c.1028G>A (p.Arg343Gln) mutation in exon 8 of TP63. The mother lacked ectrodactyly, indicating a diagnosis of RHS, whereas the girl presented with all three major features (ectrodactyly, ectodermal dysplasia, clefting) and different minor features (including small and brittle nails, and recurrent conjunctivitis believed to be because of stenotic and blo…
A Roma founder BIN1 mutation causes a novel phenotype of centronuclear myopathy with rigid spine
2018
ObjectiveTo describe a large series of BIN1 patients, in which a novel founder mutation in the Roma population of southern Spain has been identified.MethodsPatients diagnosed with centronuclear myopathy (CNM) at 5 major reference centers for neuromuscular disease in Spain (n = 53) were screened for BIN1 mutations. Clinical, histologic, radiologic, and genetic features were analyzed.ResultsEighteen patients from 13 families carried the p.Arg234Cys variant; 16 of them were homozygous for it and 2 had compound heterozygous p.Arg234Cys/p.Arg145Cys mutations. Both BIN1 variants have only been identified in Roma, causing 100% of CNM in this ethnic group in our cohort. The haplotype analysis confi…
Upregulation of the netrin receptor (DCC) gene during activation of b lymphocytes and modulation by interleukins.
2001
The DCC (deleted in colon cancer) gene has a brain restricted high expression pattern. It encodes a transmembrane protein of the immunoglobulin superfamily identified as the netrin-1 receptor. It might be a member of the so called "brain-lymphoid" molecules, which control key cell surface events. To test this hypothesis we have assessed the DCC mRNA level in human normal and malignant myeloid and lymphoid cells. A high mRNA content has been observed only in mature B cells at the secreting or presecreting stage. Expression of DCC was also assessed in the anti-CD40 model of immunopoiesis. Activation of purified tonsillar B cells by anti-CD 40 antibody strongly increased the DCC mRNA level and…
Lymph node metastasis in lower lip squamous cell carcinoma in relation to tumour size, histologic variables and p27Kip1 protein expression.
2003
We studied a consecutive series of 95 patients undergoing radical surgical resection of lower lip squamous cell carcinoma (LLSCC) to assess the correlation between lymph node status and several prognostic variables, such as sex and age, tumour size, histologic grading, maximal microscopic tumour thickness, perineural infiltration and p27Kip1 protein status, to see which of these might be predictive of the development of lymph node metastases. Statistical analysis demonstrated a significant association between node status and tumour size, histological grading, maximal thickness, perineural invasion and p27Kip1 protein expression; additionally to node metastasis, low p27Kip1 protein expressio…
Overexpression of p63 is associated with radiation resistance and prognosis in oral squamous cell carcinoma
2010
Summary Background : The tumor suppressor homologue p63 is expressed in basal and parabasal layers of intraoral mucosa. Full length transcripts with transactivational domain (TA forms) present with homology to p53 and implicate functions governing cell proliferation, differentiation and apoptosis control. To date studies show an increase of p63 expression in oral dysplasia and additionally high expression levels correlated with poor prognosis for patients with OSCC, whereas a possible link to radiation resistance of tumors has not been investigated yet. In the present study we tested the hypothesis for p63 being a marker of radioresistance and overall survival in OSCC. Methods : p63 Express…
DLG5 variants do not influence susceptibility to inflammatory bowel disease in the Scottish population
2005
Introduction: Recent data have suggested that specific haplotypic variants of the DLG5 gene on chromosome 10q23 may be associated with susceptibility to inflammatory bowel disease (IBD) in Germany. Haplotype D, notably characterised by the presence of a G→A substitution at nucleotide 113, was associated with susceptibility to Crohn’s disease (CD) whereas an extended haplotype A conferred protection. Aims: Association of DLG5 haplotypic variants with disease susceptibility, genotype-phenotype relationships, and epistasis with CARD15 was investigated in the Scottish population. Patients and methods: A total of 374 CD, 305 ulcerative colitis (UC), and 294 healthy controls (HC) were studied. Ge…
Promyelocytic leukemia (PML) gene expression is a prognostic factor in ampullary cancer patients
2008
Background: Promyelocytic leukemia (PML) tumor suppressor gene plays a key role in acute PML pathogenesis but its involvement in pathogenesis and prognosis of solid cancers has not been defined yet. Patients and methods: In all, 62 ampullary adenocarcinoma patients who underwent curative surgery between 1996 and 2005 were included. Expression analysis of PML was carried out by immunohistochemical staining and correlated with disease-free survival (DFS) and overall survival (OS). Results: In 24 tumor specimens (38.7%), PML was classified as absent, in 16 (25.8%) as focally expressed and in 22 (35.5%) as diffusely expressed. By univariate analysis, DFS was significantly influenced by patholog…