1,862 research outputs found
Relazione tra l’espressione del repressore trascrizionale MBP-1 e di miRNAs nel carcinoma mammario
No full textMBP-1 (Myc-promoter-binding-protein-1) è una proteina di 37 kDa, prodotta dalla traduzione alternativa del mRNA del gene ENO1, codificante per l’enzima glicolitico α-enolasi. MBP-1 svolge il ruolo di repressore trascrizionale agendo direttamente sul promotore di c-MYC, ERBB2 e COX2, tutti geni coinvolti in diverse fasi della progressione tumorale (1-3). Nei carcinomi duttali infiltranti della mammella (IDC), l’espressione di MBP-1 è inversamente correlata alla comparsa di metastasi linfonodali e di recidive (4). In diverse linee cellulari tumorali l’overespressione di MBP-1 risulta nella riduzione della proliferazione cellulare e dell’invasività e in un aumento nella morte cellulare per apoptosi. Recentemente è stato osservato che, in cellule di carcinoma prostatico, MBP-1 attiva la trascrizione del miR-29b che, a sua volta, regola negativamente l’espressione di proteine anti-apoptotiche e pro-metastatiche, coinvolte nella progressione tumorale (5).
Per approfondire le relazioni funzionali tra MBP-1, miR-29b ed eventuali altri miRNAs, l’espressione della proteina MBP-1 e di miRNAs è stata analizzata in una linea cellulare di carcinoma mammario ed in tumori primari mammari (IDC) tramite qRT-PCR, western blot ed analisi microarray. Differenze nei livelli relativi d’espressione di MBP-1 e miR-29b sono state rilevate sia nelle cellule che nei tumori. L’analisi tramite microarray ha permesso di identificare altri 52 miRNAs differenzialmente espressi in un modello cellulare che permette l’overespressione di MBP-1. Dall’analisi bioinformatica dei dati ottenuti emerge che i geni target di alcuni dei miRNA identificati sono espressi differenzialmente in tumori positivi e negativi per MBP-1, e che questi geni agiscono a livello di rilevanti network regolativi, che riguardano l’adesione e la regolazione della migrazione cellulare.
I dati ottenuti permettono di ipotizzare che MBP-1 intervenga nella regolazione della proliferazione e della progressione tumorale agendo direttamente sull’espressione dei geni coinvolti in questi processi o indirettamente mediante la regolazione dell’espressione di microRNA.
Bibliografia:
1. Ray R, Miller DM: Cloning and characterization of a human c-myc promoter-binding protein. Mol Cell Biol 1991, 11(4):2154-2161
2. Contino F, Mazzarella C, Ferro A, Lo Presti M, Roz E, Lupo C, Perconti G, Giallongo A, Feo S: Negative transcriptional control of ERBB2 gene by MBP-1 and HDAC1: diagnostic implications in breast cancer. BMC cancer 2013, 13:81.
3. Hsu KW, Hsieh RH, Wu CW, Chi CW, Lee YH, Kuo ML, Wu KJ, Yeh TS: MBP-1 suppresses growth and metastasis of gastric cancer cells through COX-2. Mol Biol Cell 2009, 20(24):5127-5137
4. Lo Presti M, Ferro A, Contino F, Mazzarella C, Sbacchi S, Roz E, Lupo C, Perconti G, Giallongo A, Migliorini P et al: Myc promoter-binding protein-1 (MBP-1) is a novel potential prognostic marker in invasive ductal breast carcinoma. PLoS One 2010, 5(9):e12961
5. Steele R, Mott JL, Ray RB: MBP-1 upregulates miR-29b that represses Mcl-1, collagens, and matrix-metalloproteinase-2 in prostate cancer cells. Genes & cancer 2010, 1(4):381-38
epsilon ' from supersymmetry with non-universal A terms?
No full textWe consider supersymmetric theories with st motivated flavour structure and unified soft terms. We investigate the possibility that an epsilon' parameter as large as the measured value be generated by flavour non-universal A terms without conflicting with the bounds from electron and neutron electric dipoles and mu --> e gamma. (C) 2000 Elsevier Science B.V. All rights reserved
P-Glycoprotein, a biological and medicinal chemistry/radiochemistry point of view
No full textP-glycoprotein is an important transporter belonging to ATP-Binding Cassette pumps (ABC-B1). This transporter plays a fundamental role in several degenerative diseases such as Alzheimer's, Parkinson's and other forms of dementia, as well as in tumors. This transporter is localized at the blood brain barrier (BBB) where it is involved in the efflux of endogenous and exogenous compounds and it is overexpressed in several tumor cell lines determining Multi Drug Resistance (MDR). In this chapter, we will examine the in vitro biological assays useful to establish the P-gp interactive mechanisms of a ligand and its potential in terms of therapy and diagnosis. In addition, examples of Structure Activity Relationship (SAR) studies of P-gp modulators will be described. Moreover, P-gp imaging by PET with different radioligands (11C and 18F -radiolabelled) will be herein discussed. Finally, the difficulty in the definition of a pharmacophore for the design of substrates, modulators and inhibitors is also critically approached in this chapter
I soggetti
No full textAll’interno di un complesso studio sulle ceramiche attiche rinvenute nella colonia greca di Gela, questo articolo analizza nello specifico i soggetti raffigurati sulle ceramiche a vernice nera e a vernice rossa di produzione attica; il lavoro è corredato da grafici quantitativi (a firma della scrivente la produzione a figure rosse dei periodi 525-500 a.C., p. 39; 500-475 a.C., pp. 42-44; 425-400 a.C., p. 47)
The Higgs as a composite Nambu-Goldstone boson
No full textThis is an introduction to theories where the Higgs is a composite Nambu-Goldstone boson of a new strongly-interacting dynamics not much above the weak scale. A general discussion is presented based on the pattern of global symmetries at low energy, and the analogy with the QCD pion is analyzed. The last part of the lectures shows how a composite Higgs can emerge as the hologram of a 5-dimensional gauge field. Copyright © 2011 by World Scientific Publishing Co. Pte. Ltd
A note on regularization methods in Kaluza-Klein theories
No full textAbstractWe comment on the presence of power-like divergences in Kaluza–Klein theories with supersymmetry breaking a là Scherk–Schwarz. By introducing a SUSY preserving regulator, we show that, in the context of a model recently proposed by Barbieri, Hall and Nomura, the 1-loop Higgs mass induced by Yukawa interactions is finite and unambiguously defined. The same result applies to similar models
Nuovi dati archeologici e archeometrici sulle anfore africane tardorepubblicane e primo imperiali: rinvenimenti da Roma (Nuovo Mercato Testaccio) e contesti di confronto
No full textFracture of high-density polyethylene used for bleach bottles
No full textHigh-density polyethylene (HDPE) can be blow-molded and used for the production of bottles for aggressive products. These products can interact both chemically and physically with the polymer constituting these containers, leading to a decrease in the performance of the material and undermining the structural integrity of the component.
A fracture mechanics approach was adopted to evaluate the Environmental Stress Cracking Resistance (ESCR) of two HDPE commercial grades used for bleach containers; two different solutions, with and without sodium hypochlorite (the main ingredient of commercial bleach solutions), were considered as aggressive environments. Size effects were studied using different test configurations and loading histories in air. The correlation between the stress intensity factor and the initiation time was found. A clear effect of the aggressive solutions on the fracture resistance of the two HDPEs was observed, irrespective of the presence of sodium hypochlorite; the effect therefore has to be ascribed to other bleach components
- …
