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91.
Hogan C 《Cellular and molecular life sciences : CMLS》2012,69(2):203-213
The majority of human cancers are initiated when a single cell in an epithelial sheet becomes transformed. Cell transformation
arises from the activation of oncoproteins and/or inactivation of tumor suppressor proteins. Recent studies have independently
revealed that interaction and communication between transformed cells and their normal neighbors have a significant impact
on the fate of the transformed cell. Several reports have shown that various phenomena occur at the interface between normal
and transformed epithelial cells following the initial transformation event. In epithelia of Drosophila melanogaster, transformed and normal cells compete for survival in a process termed cell competition. This review will summarize current
research and discuss the impact of these studies on our understanding of how primary tumors emerge and develop within a normal
epithelium. 相似文献
92.
The intestinal epithelium tuft cells: specification and function 总被引:1,自引:1,他引:0
The intestinal epithelium, composed of at least seven differentiated cell types, represents an extraordinary model to understand the details of multi-lineage differentiation, a question that is highly relevant in developmental biology as well as for clinical applications. This review focuses on intestinal epithelial tuft cells that have been acknowledged as a separate entity for more than 60?years but whose function remains a mystery. We discuss what is currently known about the molecular basis of tuft cell fate and differentiation and why elucidating tuft cell function has been so difficult. Finally, we summarize the current hypotheses on their potential involvement in diseases of the gastro-intestinal tract. 相似文献
93.
Frequent somatic mutations in MAP3K5 and MAP3K9 in metastatic melanoma identified by exome sequencing 总被引:1,自引:0,他引:1
Stark MS Woods SL Gartside MG Bonazzi VF Dutton-Regester K Aoude LG Chow D Sereduk C Niemi NM Tang N Ellis JJ Reid J Zismann V Tyagi S Muzny D Newsham I Wu Y Palmer JM Pollak T Youngkin D Brooks BR Lanagan C Schmidt CW Kobe B MacKeigan JP Yin H Brown KM Gibbs R Trent J Hayward NK 《Nature genetics》2012,44(2):165-169
We sequenced eight melanoma exomes to identify new somatic mutations in metastatic melanoma. Focusing on the mitogen-activated protein (MAP) kinase kinase kinase (MAP3K) family, we found that 24% of melanoma cell lines have mutations in the protein-coding regions of either MAP3K5 or MAP3K9. Structural modeling predicted that mutations in the kinase domain may affect the activity and regulation of these protein kinases. The position of the mutations and the loss of heterozygosity of MAP3K5 and MAP3K9 in 85% and 67% of melanoma samples, respectively, together suggest that the mutations are likely to be inactivating. In in vitro kinase assays, MAP3K5 I780F and MAP3K9 W333* variants had reduced kinase activity. Overexpression of MAP3K5 or MAP3K9 mutants in HEK293T cells reduced the phosphorylation of downstream MAP kinases. Attenuation of MAP3K9 function in melanoma cells using siRNA led to increased cell viability after temozolomide treatment, suggesting that decreased MAP3K pathway activity can lead to chemoresistance in melanoma. 相似文献
94.
TGFB2 mutations cause familial thoracic aortic aneurysms and dissections associated with mild systemic features of Marfan syndrome 总被引:1,自引:0,他引:1
C Boileau DC Guo N Hanna ES Regalado D Detaint L Gong M Varret SK Prakash AH Li H d'Indy AC Braverman B Grandchamp CS Kwartler L Gouya RL Santos-Cortez M Abifadel SM Leal C Muti J Shendure MS Gross MJ Rieder A Vahanian DA Nickerson JB Michel;National Heart Lung Blood Institute 《Nature genetics》2012,44(8):916-921
A predisposition for thoracic aortic aneurysms leading to acute aortic dissections can be inherited in families in an autosomal dominant manner. Genome-wide linkage analysis of two large unrelated families with thoracic aortic disease followed by whole-exome sequencing of affected relatives identified causative mutations in TGFB2. These mutations-a frameshift mutation in exon 6 and a nonsense mutation in exon 4-segregated with disease with a combined logarithm of odds (LOD) score of 7.7. Sanger sequencing of 276 probands from families with inherited thoracic aortic disease identified 2 additional TGFB2 mutations. TGFB2 encodes transforming growth factor (TGF)-β2, and the mutations are predicted to cause haploinsufficiency for TGFB2; however, aortic tissue from cases paradoxically shows increased TGF-β2 expression and immunostaining. Thus, haploinsufficiency for TGFB2 predisposes to thoracic aortic disease, suggesting that the initial pathway driving disease is decreased cellular TGF-β2 levels leading to a secondary increase in TGF-β2 production in the diseased aorta. 相似文献
95.
96.
Benzinou M Creemers JW Choquet H Lobbens S Dina C Durand E Guerardel A Boutin P Jouret B Heude B Balkau B Tichet J Marre M Potoczna N Horber F Le Stunff C Czernichow S Sandbaek A Lauritzen T Borch-Johnsen K Andersen G Kiess W Körner A Kovacs P Jacobson P Carlsson LM Walley AJ Jørgensen T Hansen T Pedersen O Meyre D Froguel P 《Nature genetics》2008,40(8):943-945
Mutations in PCSK1 cause monogenic obesity. To assess the contribution of PCSK1 to polygenic obesity risk, we genotyped tag SNPs in a total of 13,659 individuals of European ancestry from eight independent case-control or family-based cohorts. The nonsynonymous variants rs6232, encoding N221D, and rs6234-rs6235, encoding the Q665E-S690T pair, were consistently associated with obesity in adults and children (P = 7.27 x 10(-8) and P = 2.31 x 10(-12), respectively). Functional analysis showed a significant impairment of the N221D-mutant PC1/3 protein catalytic activity. 相似文献
97.
Le Goff C Morice-Picard F Dagoneau N Wang LW Perrot C Crow YJ Bauer F Flori E Prost-Squarcioni C Krakow D Ge G Greenspan DS Bonnet D Le Merrer M Munnich A Apte SS Cormier-Daire V 《Nature genetics》2008,40(9):1119-1123
Geleophysic dysplasia is an autosomal recessive disorder characterized by short stature, brachydactyly, thick skin and cardiac valvular anomalies often responsible for an early death. Studying six geleophysic dysplasia families, we first mapped the underlying gene to chromosome 9q34.2 and identified five distinct nonsense and missense mutations in ADAMTSL2 (a disintegrin and metalloproteinase with thrombospondin repeats-like 2), which encodes a secreted glycoprotein of unknown function. Functional studies in HEK293 cells showed that ADAMTSL2 mutations lead to reduced secretion of the mutated proteins, possibly owing to the misfolding of ADAMTSL2. A yeast two-hybrid screen showed that ADAMTSL2 interacts with latent TGF-beta-binding protein 1. In addition, we observed a significant increase in total and active TGF-beta in the culture medium as well as nuclear localization of phosphorylated SMAD2 in fibroblasts from individuals with geleophysic dysplasia. These data suggest that ADAMTSL2 mutations may lead to a dysregulation of TGF-beta signaling and may be the underlying mechanism of geleophysic dysplasia. 相似文献
98.
FCGR3B copy number variation is associated with susceptibility to systemic, but not organ-specific, autoimmunity 总被引:13,自引:0,他引:13
Fanciulli M Norsworthy PJ Petretto E Dong R Harper L Kamesh L Heward JM Gough SC de Smith A Blakemore AI Froguel P Owen CJ Pearce SH Teixeira L Guillevin L Graham DS Pusey CD Cook HT Vyse TJ Aitman TJ 《Nature genetics》2007,39(6):721-723
Naturally occurring variation in gene copy number is increasingly recognized as a heritable source of susceptibility to genetically complex diseases. Here we report strong association between FCGR3B copy number and risk of systemic lupus erythematosus (P = 2.7 x 10(-8)), microscopic polyangiitis (P = 2.9 x 10(-4)) and Wegener's granulomatosis in two independent cohorts from the UK (P = 3 x 10(-3)) and France (P = 1.1 x 10(-4)). We did not observe this association in the organ-specific Graves' disease or Addison's disease. Our findings suggest that low FCGR3B copy number, and in particular complete FCGR3B deficiency, has a key role in the development of systemic autoimmunity. 相似文献
99.
Sequence variants in the autophagy gene IRGM and multiple other replicating loci contribute to Crohn's disease susceptibility 总被引:14,自引:0,他引:14
Parkes M Barrett JC Prescott NJ Tremelling M Anderson CA Fisher SA Roberts RG Nimmo ER Cummings FR Soars D Drummond H Lees CW Khawaja SA Bagnall R Burke DA Todhunter CE Ahmad T Onnie CM McArdle W Strachan D Bethel G Bryan C Lewis CM Deloukas P Forbes A Sanderson J Jewell DP Satsangi J Mansfield JC;Wellcome Trust Case Control Consortium Cardon L Mathew CG 《Nature genetics》2007,39(7):830-832
A genome-wide association scan in individuals with Crohn's disease by the Wellcome Trust Case Control Consortium detected strong association at four novel loci. We tested 37 SNPs from these and other loci for association in an independent case-control sample. We obtained replication for the autophagy-inducing IRGM gene on chromosome 5q33.1 (replication P = 6.6 x 10(-4), combined P = 2.1 x 10(-10)) and for nine other loci, including NKX2-3, PTPN2 and gene deserts on chromosomes 1q and 5p13. 相似文献
100.
Knowledge transfer across different contexts has become an increasingly prevalent feature of current science. As such, it is a relevant topic also for historians and philosophers of science. This special issue presents a set of papers that study knowledge transfer in various disciplines. The contributions approach the topic from 1) an integrated history and philosophy of science perspective, 2) a systematic philosophical perspective, or 3) a historical perspective. Taken together, they give a broad introduction into the topic and offer a set of conceptual resources for the study of knowledge transfer in multiple contexts. 相似文献