1,721,299 research outputs found
Characterization of the biological role of RIPK2 in carcinogenesis
No full textBackground. Cell survival, inflammation and cell death are the main processes involved in cellular homeostasis. The deregulation of these events can lead to the onset of several pathologies, including cancer. Receptor-Interacting Serine/Threonine Protein Kinase 2 (RIPK2) plays a key signalling role in host defence, inflammation as well as in regulated cell death (1). Till now, it is known that RIPK2, through its CARD functional domain, is able to trigger the activation of NF-kB or the MAP kinase pathway playing a fundamental role in the immune response and inflammation (2) but little scientific evidence explain the direct involvement of the protein kinase in cancer, particularly in haematological malignancies (3). Hence, more studies are necessary to better clarify its involvement in tumorigenesis and metastasis. Aim: The aim of our work is to better define the biological role of RIPK2 in cancer with a particular focus in leukaemia, in order to clarify its molecular mechanisms. Here we also provide a deeper insight into the molecular mechanism of action of new epi-drugs, highlighting their ability to directly target RIPK2. Methods: To achieve the various objectives, we have made use of RT-qPCR, Western Blot, Flow Cytometry, Immunoprecipitation, Immunofluorescence. Results. RIPK2 is differentially expressed in tumour cell lines. In particular, we focused our attention on two myeloid cell lines (U-937 and HL-60) with a different degree of differentiation for subsequent proteomic analyses and cellular localization studies. Furthermore, RIPK2 appears to be modulated after the treatment with a previously characterized epi-drug, highlighting the possible involvement of RIPK2 in the cell death process. Conclusions. The effects observed by the compound strengthen its potential role as an anti-tumor agent in leukaemia mediated by RIPK2 expression. However, further molecular and enzymatic investigations will be necessary to better understand the biological role of RIPK2 in carcinogenesis, especially in hematological malignancies
Epi-drugs to fight cancer: From chemistry to cancer treatment, the road ahead
No full textIn addition to genetic events, a variety of epigenetic events have been widely reported to contribute to file Onset of many diseases including cancer. DNA methylation and historic modifications (such as acetylation, methylation, sumoylation, and phosphorylation) involving chromatin remodelling are among the most studied epigenetic mechanisms for regulation of gene expression leading, when altered, to some diseases. Epigenetic therapy tries to reverse the aberrations followed to the disruption of the balance of the epigenetic signalling ways through the use of both natural compounds and synthetic molecules, active on Specific epi-targets. Such epi-drugs are, for example, inhibitors of DNA methyltransferases, histone deacetylases, histone acetyltransferases, histone methyltransferases, and histone demethylases. In this review we will focus Oil the chemical aspects Of such molecules joined to their effective (or potential) application in cancer therapy. (C) 2008 Elsevier Ltd. All rights reserved
IMMUNOMODULATORY ACTIVITY OF POLYPHENOLIC EXTRACTS FROM STRAWBERRY CULTIVARS
No full textBackground: In recent years, strawberry has received much attention for its high nutritional value and potential benefits for human health due to its rich phytochemical profile and low observed toxicity1. Previous research has shown that polyphenols have anti-inflammatory, antimicrobial, antioxidant, anticarcinogenic, diabetic, and neuroprotective properties2. However, their individual effects on different cell signalling pathways remain to be elucidated3.
Aim: This study will aim to investigate the immunomodulatory activity of four strawberry cultivars (Marimbella, Red Sara, Gioelita, Melissa) in order to identify their potential anticancer role.
Methods: Strawberry extracts were used to treat in vitro cellular models of THP1-derived macrophages induced with lipopolysaccharides (LPS). Techniques as Western blot, qRT-PCR, flow cytometry, Griess assay were additionally performed.
Results. Given the strong interaction between immune cells and the tumour microenvironment in mediating the inflammatory response, we determined i) the release of specific pro-inflammatory and anti-inflammatory mediators into the tumour microenvironment, ii) the inhibition of both nitric oxide (NO) synthesis and intracellular levels of reactive oxygen species (ROS), and iii) the modulation of regulated cell death pathways (RCD) involved in inflammation.
Conclusions: Defining the immunomodulatory effects induced by polyphenolic extracts of strawberry cultivars will provide useful information on the restoration of the compromised immune system in cancer. This scenario highlights the fundamental role of phenolic substances in exerting anti-tumour mechanisms
NETosis in pathologies: a preliminary study for NETs detection in vitro
No full textBackground: Neutrophils are the major participants in NETosis, a novel kind of regulated cell death (RCD) that has recently emerged. As a result, neutrophils not only serve as the initial line of defense for the host, but they also help to mediate the new RCD by releasing neutrophil extracellular traps (NETs).1 NETosis is characterized by sequence of events: intracellular membranes disintegrate and proteases from granules enter the nucleus, followed by hypercitrullination of histones, chromatin decondensation and extrusion of nuclear material from the cell. Then, NETs decorated by decondensed chromatin, modified histones and granular enzymes are released from cells. 2
Physiologically, NETs entrap bacteria and provide a natural defence against inflammation but an exacerbated release of NETs markers can exert pro-thrombotic and pro-inflammatory effects and are resulted implicated in many diseases such as hyperglycaemia, diabetes and its complications. 3
Aim: The project has the purpose to to study in depth NETosis pathway and its implications in pathogenesis. Specifically, will be characterize the epi-modulation of NETs formation in samples derived from cancer and diabetic patients.
Materials and methods: differentiation of HL60 FOR 5 days with Dimethyl sulfoxide or All-trans retinoic acid. May Grunwald Giemsa staining. Immunofluorescence staining Anti-MPO and H3cit. Flow based assay to detect NETs. ROS assay.
Result: several methods have been developed o investigate NETosis. NETs formation has been identified after epi drugs induction.
The methods we are using to detect NETs and to evaluate NETosis markers are efficient to study NETosis in blood samples from patients.
Conclusions: NETosis is a recent discovered RCD that resulted de-regulated in many pathologies. The characterization of NETosis mechanism and complete understanding of NETosis role in pathogenesis could provide new prognostic markers and novels therapeutic targets
CHARACTERIZATION OF NEW RIPKs FAMILY MEMBERS: HIGHLIGHTS ON THE BIOLOGICAL ROLE OF RIPK2 AND RIPK4 IN CANCER
No full textReceptor-Interacting Protein Kinases (RIPKs) are a seven-member family of Ser/Thr protein kinases involved in host defense, inflammatory phenomena as well as in cell death. To date their role in tumorigenesis is still unclear. Little scientific evidence explains the direct involvement of RIPK2 and RIPK4 in pathogenesis, especially in cancer. Several cell death regulation strategies have been studied in order to improve anticancer therapies and, among these, the study of the RIP kinase family is particularly interesting, which offers a therapeutic alternative in cases of resistance to apoptotic processes. It is known that RIPK2, through its CARD functional domain, is able to trigger the activation of NF-kB or the MAP kinase pathway, playing a fundamental role in the immune response and inflammation while RIPK4 appears to participate both physically and functionally in several TRAF-dependent pathways leading to the activation of NF-kB pathway. Methods: Western blot, RT-qPCR, Immunoprecipitation, Transfection. Results. Since both kinases are differentially expressed in different cancer types and the molecular mechanisms involved are poorly characterized, one of the main objectives of the project is to characterize the oncogenic role of these proteins by studying key molecular interactors and activated protein complexes. For this purpose, different cancer cell models exhibiting variable expression levels were chosen. Jurkat and Raji tumoral cell lines, in which RIPK2 is respectively poor and high expressed, as well as HL-60 and PANC-1 tumoral cell lines for RIPK4 investigation will be considered. To identify molecular players, MS/MS analysis coupled immunoprecipitation experiments were performed. Waiting for these results, molecular screening experiments have been started in order to identify molecules that modulate the expression of these kinases, that are structural scaffolds useful for the synthesis of new molecules. Conclusions. Further studies will be needed to better understand the biological activity of the investigated proteins and to understand the possible cross talk between different family members
Identification of 4-hydroxyquinolines inhibitors of p300/CBP histone acetyltransferases
No full textWe identified a series of 4-hydroxyquinolines bearing a C1 to C15 alkyl chain at the C2 position and a carbethoxy/carboxy group at the C3 position of the quinoline nucleus (MC compounds), endowed with selective inhibitory activity against the p300/CBP HAT enzymes. Enzyme inhibition was investigated using in vitro HAT assays and by western blot analysis of cellular lysates to examine the acetylation levels of histone H3 and alpha-tubulin. When tested in U937 cells, some compounds displayed pro-apoptotic or cytodifferentiating properties. (C) 2009 Elsevier Ltd. All rights reserved
Characterization of Sirtuin Inhibitors in Nematodes Expressing a Muscular Dystrophy Protein Reveals Muscle Cell and Behavioral Protection by Specific Sirtinol Analogues
No full textIn oculopharyngeal muscular dystrophy (OPMD), a disease caused by polyalanine expansion in the nuclear protein PABPN1, the genetic inhibition or sirtuins and treatment with sirtuin inhibitors protect from mutant PABPN1 toxicity in transgenic nematodes. Here, we tested the SIRT1/2 inhibitors 1-12, bearing different degrees of inhibition, for protection against mutant PABPN1 toxicity in Caenorhabditis elegans. Compounds 2, 4, and 11 were the most efficient, revealing a potential therapeutic application for muscle cell protection in OPMD
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
