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排序方式: 共有220条查询结果,搜索用时 31 毫秒
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Karnoub AE Dash AB Vo AP Sullivan A Brooks MW Bell GW Richardson AL Polyak K Tubo R Weinberg RA 《Nature》2007,449(7162):557-563
Mesenchymal stem cells have been recently described to localize to breast carcinomas, where they integrate into the tumour-associated stroma. However, the involvement of mesenchymal stem cells (or their derivatives) in tumour pathophysiology has not been addressed. Here, we demonstrate that bone-marrow-derived human mesenchymal stem cells, when mixed with otherwise weakly metastatic human breast carcinoma cells, cause the cancer cells to increase their metastatic potency greatly when this cell mixture is introduced into a subcutaneous site and allowed to form a tumour xenograft. The breast cancer cells stimulate de novo secretion of the chemokine CCL5 (also called RANTES) from mesenchymal stem cells, which then acts in a paracrine fashion on the cancer cells to enhance their motility, invasion and metastasis. This enhanced metastatic ability is reversible and is dependent on CCL5 signalling through the chemokine receptor CCR5. Collectively, these data demonstrate that the tumour microenvironment facilitates metastatic spread by eliciting reversible changes in the phenotype of cancer cells. 相似文献
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This paper publishes the correspondence between S. Germain and C.F. Gauss. The mathematical notes enclosed in her letters are published for the first time. These notes, in which she submitted some of her results, proofs and conjectures to Gauss for his evaluation, were inspired by her study of the Disquisitiones Arithmeticae. The interpretation of these mathematical notes not only shows how deeply she went into Gauss’s treatise and mastered it long before any other mathematician, but also, more importantly, shows that she obtained interesting results in the theory of power residues that have never previously been attributed to her. 相似文献
187.
iASPP preferentially binds p53 proline-rich region and modulates apoptotic function of codon 72-polymorphic p53 总被引:6,自引:0,他引:6
Bergamaschi D Samuels Y Sullivan A Zvelebil M Breyssens H Bisso A Del Sal G Syed N Smith P Gasco M Crook T Lu X 《Nature genetics》2006,38(10):1133-1141
iASPP is one of the most evolutionarily conserved inhibitors of p53, whereas ASPP1 and ASPP2 are activators of p53. We show here that, in addition to the DNA-binding domain, the ASPP family members also bind to the proline-rich region of p53, which contains the most common p53 polymorphism at codon 72. Furthermore, the ASPP family members, particularly iASPP, bind to and regulate the activity of p53Pro72 more efficiently than that of p53Arg72. Hence, escape from negative regulation by iASPP is a newly identified mechanism by which p53Arg72 activates apoptosis more efficiently than p53Pro72. 相似文献
188.
Choudhury AR Ju Z Djojosubroto MW Schienke A Lechel A Schaetzlein S Jiang H Stepczynska A Wang C Buer J Lee HW von Zglinicki T Ganser A Schirmacher P Nakauchi H Rudolph KL 《Nature genetics》2007,39(1):99-105
Telomere shortening limits the proliferative lifespan of human cells by activation of DNA damage pathways, including upregulation of the cell cycle inhibitor p21 (encoded by Cdkn1a, also known as Cip1 and Waf1)) (refs. 1-5). Telomere shortening in response to mutation of the gene encoding telomerase is associated with impaired organ maintenance and shortened lifespan in humans and in mice. The in vivo function of p21 in the context of telomere dysfunction is unknown. Here we show that deletion of p21 prolongs the lifespan of telomerase-deficient mice with dysfunctional telomeres. p21 deletion improved hematolymphopoiesis and the maintenance of intestinal epithelia without rescuing telomere function. Moreover, deletion of p21 rescued proliferation of intestinal progenitor cells and improved the repopulation capacity and self-renewal of hematopoietic stem cells from mice with dysfunctional telomeres. In these mice, apoptotic responses remained intact, and p21 deletion did not accelerate chromosomal instability or cancer formation. This study provides experimental evidence that telomere dysfunction induces p21-dependent checkpoints in vivo that can limit longevity at the organismal level. 相似文献
189.
Crow YJ Leitch A Hayward BE Garner A Parmar R Griffith E Ali M Semple C Aicardi J Babul-Hirji R Baumann C Baxter P Bertini E Chandler KE Chitayat D Cau D Déry C Fazzi E Goizet C King MD Klepper J Lacombe D Lanzi G Lyall H Martínez-Frías ML Mathieu M McKeown C Monier A Oade Y Quarrell OW Rittey CD Rogers RC Sanchis A Stephenson JB Tacke U Till M Tolmie JL Tomlin P Voit T Weschke B Woods CG Lebon P Bonthron DT Ponting CP Jackson AP 《Nature genetics》2006,38(8):910-916
Aicardi-Goutières syndrome (AGS) is an autosomal recessive neurological disorder, the clinical and immunological features of which parallel those of congenital viral infection. Here we define the composition of the human ribonuclease H2 enzyme complex and show that AGS can result from mutations in the genes encoding any one of its three subunits. Our findings demonstrate a role for ribonuclease H in human neurological disease and suggest an unanticipated relationship between ribonuclease H2 and the antiviral immune response that warrants further investigation. 相似文献
190.
Deficiency of hyccin, a newly identified membrane protein, causes hypomyelination and congenital cataract 总被引:1,自引:0,他引:1
Zara F Biancheri R Bruno C Bordo L Assereto S Gazzerro E Sotgia F Wang XB Gianotti S Stringara S Pedemonte M Uziel G Rossi A Schenone A Tortori-Donati P van der Knaap MS Lisanti MP Minetti C 《Nature genetics》2006,38(10):1111-1113
We describe a new autosomal recessive white matter disorder ('hypomyelination and congenital cataract') characterized by hypomyelination of the central and peripheral nervous system, progressive neurological impairment and congenital cataract. We identified mutations in five affected families, resulting in a deficiency of hyccin, a newly identified 521-amino acid membrane protein. Our study highlights the essential role of hyccin in central and peripheral myelination. 相似文献