Search results for "Transcription factor"

Notch signalling is off and is uncoupled from HES1 expression in Ewing's sarcoma

2010

Notch can act as an oncogene or as a tumour suppressor and thus can either promote or inhibit tumour cell growth. To establish Notch status in Ewing's sarcoma family of tumours (ESFT), we investigated the Notch pathway by gene expression profiling meta-analysis or immunohistochemistry in samples obtained from 96 and 24 ESFT patients, respectively. We found that although Notch receptors were highly expressed, Notch did not appear to be active, as evidenced by the absence of Notch receptors in cell nuclei. In contrast, we show that Notch receptors known to be active in colon adenocarcinoma, hepatocarcinoma, and pancreatic carcinoma stain cell nuclei in these tumours. High expression of the No…

Immunohistochemical study of correlation between histologic subtype and expression of epithelial-mesenchymal transition-related proteins in synovial …

2011

Context.—Synovial sarcomas are mesenchymal tumors with epithelial nature and comprise biphasic and monophasic fibrous subtypes. However, factors determining epithelial or spindle cell differentiation are still unexplored. Aberrant epithelial-mesenchymal transition has been implicated in the pathogenesis of diverse human malignancies.Objective.—To analyze the correlation between cellular phenotype and expression of proteins associated with different epithelial-mesenchymal transition-related pathways.Design.—Immunohistochemical analysis of E-cadherin, Snail, Slug, and dysadherin, components of the Wnt/wingless and PI3K/Akt pathways, was performed on 14 biphasic and 27 monophasic fibrous tumor…

In Vitro Identification and Characterization of CD133pos Cancer Stem-Like Cells in Anaplastic Thyroid Carcinoma Cell Lines

2008

BackgroundRecent publications suggest that neoplastic initiation and growth are dependent on a small subset of cells, termed cancer stem cells (CSCs). Anaplastic Thyroid Carcinoma (ATC) is a very aggressive solid tumor with poor prognosis, characterized by high dedifferentiation. The existence of CSCs might account for the heterogeneity of ATC lesions. CD133 has been identified as a stem cell marker for normal and cancerous tissues, although its biological function remains unknown.Methodology/principal findingsATC cell lines ARO, KAT-4, KAT-18 and FRO were analyzed for CD133 expression. Flow cytometry showed CD133(pos) cells only in ARO and KAT-4 (64+/-9% and 57+/-12%, respectively). These …

SOX2 and BCL-2 Expressions in Odontogenic Keratocyst and Ameloblastoma

2020

Background The purpose of this experimental study was to compare the immunohistochemical expression of SOX2 and BCL-2 in Odontogenic Keratocyst (OKC) and Ameloblastoma (AB) specimens, and to identify a possible correlation in their expression. Material and Methods Immunohistochemical analysis was performed to evaluate SOX2 and BCL-2 expression in OKC (n = 20) and AB (n = 20). The immunoexpression was analyzed by a quantitative and qualitative scoring system. The comparison between the immunoexpression of SOX 2 and BCL-2 was assessed by the Mann-Whitney U-test. Spearman’s correlation coefficient evaluated the correlation between SOX2 and BCL-2 expressions. Results SOX2 and BCL-2 expression w…

Reply to “Primary cutaneous biphasic sarcomatoid basal cell carcinoma with myoepithelial carcinoma differentiation. Is it a new variant of sarcomatoi…

2020

Phosphorylation of peroxisome proliferator-activated receptor α in rat Fao cells and stimulation by ciprofibrate

1999

The basic mechanism(s) by which peroxisome proliferators activate peroxisome proliferator-activated receptors (PPARs) is (are) not yet fully understood. Given the diversity of peroxisome proliferators, several hypotheses of activation have been proposed. Among them is the notion that peroxisome proliferators could activate PPARs by changing their phosphorylation status. In fact, it is well known that several members of the nuclear hormone receptor superfamily are regulated by phosphorylation. In this report, we show that the rat Fao hepatic-derived cell line, known to respond to peroxisome proliferators, exhibited a high content of PPARalpha. Alkaline phosphatase treatment of Fao cell lysat…

The analysis of modified peroxisome proliferator responsive elements of the peroxisomal bifunctional enzyme in transfected HepG2 cells reveals two re…

1995

AbstractPeroxisome proliferators (PPs) are non-genotoxic carcinogens in rodents. They can induce the expression of numerous genes via the heterodimerization of two members of the steroid hormone receptor superfamily, called the peroxisome proliferator-activated receptor (PPAR) and the 9-cis retinoic acid receptor (RXR). Many of the PP responsive genes possess a peroxisome proliferator response element (PPRE) formed by two TGACCT-related motifs. The bifunctional enzyme (HD) PPRE contains 3 such motifs, creating DR1 and DR2 sequences. PPAR and RXR regulate transcription via the DR1 element while DR2 modulates the expression of the gene via auxiliary factors in HepG2 cells.

Functional characterization of a peroxisome proliferator response-element located in the intron 3 of rat peroxisomal thiolase B gene.

2003

Expression of the rat peroxisomal 3-ketoacyl-CoA thiolase gene B is induced by peroxisome proliferators. Although a sequence element like a peroxisome proliferator-activated receptor (PPAR)-binding site is located in the promoter region of this gene, we previously found that this element is competent for the activation by hepatocyte nuclear factor-4, but not functional with PPARalpha. We describe here a new peroxisome proliferator-response element located in the intron 3 (+1422/+1434) that binds in vitro the PPARalpha/retinoid X receptor alpha heterodimer and confers the induction by PPARalpha in transfection assays. We propose a model of regulation of the rat thiolase B gene involving thos…

The immunosuppressive activity of artemisinin‐type drugs towards inflammatory and autoimmune diseases

2021

The sesquiterpene lactone artemisinin from Artemisia annua L. is well established for malaria therapy, but its bioactivity spectrum is much broader. In this review, we give a comprehensive and timely overview of the literature regarding the immunosuppressive activity of artemisinin-type compounds toward inflammatory and autoimmune diseases. Numerous receptor-coupled signaling pathways are inhibited by artemisinins, including the receptors for interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), β3-integrin, or RANKL, toll-like receptors and growth factor receptors. Among the receptor-coupled signal transducers are extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinas…

Effects of triterpenes on the immune system.

2010

Ethnopharmacological relevance: Triterpenes, which comprise a broad chemical group of active principles, are implicated in the mechanisms of action and pharmacological effects of many medicinal plants used in folk medicine against diseases in which the immune system is implicated. They have been described as anti-inflammatory, antiviral, antimicrobial, and antitumoral agents, as well as being immunomodulator compounds. Several of them are implicated in the resolution of immune diseases, although their effects have not always been clearly correlated. Aim of the review: The aim of this review is to compile relevant data on the mechanisms of action of triterpenes isolated from active ethnomedi…