Search results for "Gene expression"
showing 10 items of 4085 documents
aPKCζ cortical loading is associated with Lgl cytoplasmic release and tumor growth in Drosophila and human epithelia
2007
Atypical protein kinase C (aPKC) and Lethal giant larvae (Lgl) regulate apical-basal polarity in Drosophila and mammalian epithelia. At the apical domain, aPKC phosphorylates and displaces Lgl that, in turn, maintains aPKC inactive at the basolateral region. The mutual exclusion of these two proteins seems to be crucial for the correct epithelial structure and function. Here we show that a cortical aPKC loading induces Lgl cytoplasmic release and massive overgrowth in Drosophila imaginal epithelia, whereas a cytoplasmic expression does not alter proliferation and epithelial overall structure. As two aPKC isoforms (iota and zeta) exist in humans and we previously showed that Drosophila Lgl i…
Genome-Wide Haplotype Analysis of Cis Expression Quantitative Trait Loci in Monocytes
2013
In order to assess whether gene expression variability could be influenced by several SNPs acting in cis, either through additive or more complex haplotype effects, a systematic genome-wide search for cis haplotype expression quantitative trait loci (eQTL) was conducted in a sample of 758 individuals, part of the Cardiogenics Transcriptomic Study, for which genome-wide monocyte expression and GWAS data were available. 19,805 RNA probes were assessed for cis haplotypic regulation through investigation of ∼2,1×109 haplotypic combinations. 2,650 probes demonstrated haplotypic p-values >104-fold smaller than the best single SNP p-value. Replication of significant haplotype effects were tested f…
Hypoxia-induced epithelial VEGF-C/VEGFR-3 upregulation in carcinoma cell lines
2008
Adaptation to hypoxia, a universal hallmark of carcinomas, is a critical step for tumor cell survival and growth. One of the principal regulators of hypoxia-responsive pathways is the transcription factor hypoxia-inducible factor-1 alpha (HIF-1 alpha). Currently, it is known that tumoral production of members of the vascular endothelial growth factor (VEGF)-family (VEGFs) may promote tumor growth and progression by acting on carcinoma cells that express the cognate receptors (VEGFRs). However, the influence of hypoxia in the formation of such a tumoral VEGF/VEGFR loop is not completely understood. In the present study we examined the potential existence of a HIF-1 alpha/VEGF/VEGFR autocrine…
Transforming growth factor-β1, β2, and β3, urokinase and parathyroid hormone-related peptide expression in 8701-BC breast cancer cells and clones
1993
8701-BC is a recently characterized cell line isolated from a primary ductal infiltrating carcinoma of the breast (d.i.c.), showing some pleomorphism in cell microanatomy at an ultrastructural level. We have obtained different sublines of 8701-BC cells by cloning in soft agar at different concentrations (0.3% and 0.6%), and we have characterized the cloned lines by some morphological and growth parameters. 8701-BC cells and clones have been submitted to analysis by reverse transcriptase-linked polymerase chain reaction to detect mRNAs of various cytokines (transforming growth factor-beta s, tumour necrosis factors, interleukin 1s, interleukin 6, parathyroid hormone-related peptide, gamma in…
Regulation of endothelial-type NO synthase expression in pathophysiology and in response to drugs.
2002
In many types of cardiovascular pathophysiology such as hypercholesterolemia and atherosclerosis, diabetes, cigarette smoking, or hypertension (with its sequelae stroke and heart failure) the expression of endothelial NO synthase (eNOS) is altered. Both up- and downregulation of eNOS have been observed, depending on the underlying disease. When eNOS is upregulated, the upregulation is often futile and goes along with a reduction in bioactive NO. This is due to an increased production of superoxide generated by NAD(P)H oxidase and by an uncoupled eNOS. A number of drugs with favorable effects on cardiovascular disease upregulate eNOS expression. The resulting increase in vascular NO producti…
Physiological mechanisms regulating the expression of endothelial-type NO synthase
2002
Although endothelial nitric oxide synthase (eNOS) is a constitutively expressed enzyme, its expression is regulated by a number of biophysical, biochemical, and hormonal stimuli, both under physiological conditions and in pathology. This review summarizes the recent findings in this field. Shear stress, growth factors (such as transforming growth factor-beta, fibroblast growth factor, vascular endothelial growth factor, and platelet-derived growth factor), hormones (such as estrogens, insulin, angiotensin II, and endothelin 1), and other compounds (such as lysophosphatidylcholine) upregulate eNOS expression. On the other hand, the cytokine tumor necrosis factor-alpha and bacterial lipopolys…
GADD45α is highly expressed in pancreatic ductal adenocarcinoma cells and required for tumor cell viability
2005
Pancreatic ductal adenocarcinoma is one of the most common causes of cancer death in the western civilization. Recently, NF-kappaB has been shown to be activated in pancreatic ductal adenocarcinoma through constitutive activation of IkappaB kinase (IKK). Inhibition of NF-kappaB by a super-inhibitor of NF-kappaB--delta-N-IkappaBalpha--resulted in impaired proliferation and induction of apoptosis, suggesting an important role of NF-kappaB in pancreatic tumorigenesis. Downstream target genes of IkappaBalpha have not been elucidated in pancreatic ductal adenocarcinoma in detail. Using expression profiling by cDNA array analysis of pancreatic ductal adenocarcinoma cell lines stably transfected w…
Development of hydroxysteroid sulfotransferase-deficient lesions during hepatocarcinogenesis in rats
1993
Rat liver cytosolic hydroxysteroid sulfotransferases form highly reactive sulfuric acid esters from some benzylic alcohols, such as 1-hydroxymethylpyrene. In this study we examined the expression of hydroxysteroid sulfotransferase a (STa) in carcinogen-induced enzyme-altered, presumably preneoplastic, rat liver foci. Female Wistar rats were given a single i.p. injection of diethylnitrosamine (0.15 mumol/g body wt) 1 day after birth to induce the liver foci. After weaning, rats were given 1-hydroxymethylpyrene or phenobarbital continuously in their diet (250 or 500 p.p.m. respectively) for a total of 120 days. Carcinogen-induced liver foci were identified by a change in the marker enzyme ade…
Cellular mechanism of action of thyroid hormones.
1987
Abstract It has emerged in the last decade that the molecular mechanism of action of thyroid hormones resembles that of steroids; thyroid hormones indeed exert their effects mainly by directly regulating gene expression, on association with specific chromatin-bound receptors. Of the two thyroid hormones, thyroxine (T4) appears to be a sort of prohormone, whereas triiodothyronine (T3) seems to be the active form; in this respect, T4-deiodination, which occurs at the level of the target tissues, may be crucial in the local homeostasis of T3. Moreover, many cellular compartments, other than the nucleus, can bind thyroid hormone, and at least some of these further sites might play some role in …
Constitutive and IFN-gamma regulated expression of IL-7 and IL-15 in human renal cell cancer.
1998
Although not structurally related, the pleiotropic cytokines interleukin-7 (IL-7) and interleukin-15 (IL-15) share a variety of biological functions including stimulation and maintenance of cellular immune responses. Cytokines, such as IL-7 or IL-15, elaborated by cells in situ, e.g. cancer cells, may be involved in shaping the quality of anti-tumor directed immune responses. We have analysed the constitutive and IFN-gamma-inducible expression of IL-15 or IL-7 mRNA, protein expression, and protein secretion in human tumor cell lines of distinct origin. IL-15 mRNA expression was detected in renal cell carcinoma (RCC), small cell lung carcinoma (SCLC), glioblastoma, neuroblastoma, mesotheliom…