PPARs are nuclear receptors activated by ligands. Activation of PPARγ leads to a reduction of adhesion and motility in some cancer models. PPARγ transcriptional activity can be negatively regulated by JNK-mediated phosphorylation.
View Article and Find Full Text PDFPPAR Res
August 2012
PPARαs are nuclear receptors highly expressed in colon cells. They can be activated by the fibrates (clofibrate, ciprofibrate etc.) used to treat hyperlipidemia.
View Article and Find Full Text PDF4-Hydroxynonenal (HNE) is an end product of lipoperoxidation with antiproliferative and proapoptotic properties in various tumors. Here we report a greater sensitivity to HNE in PC3 and LNCaP cells compared to DU145 cells. In contrast to PC3 and LNCaP cells, HNE-treated DU145 cells showed a smaller reduction in growth and did not undergo apoptosis.
View Article and Find Full Text PDFFree Radic Biol Med
January 2011
Histone deacetylase inhibitors (HDACIs) are promising antineoplastic agents for the treatment of cancer. Here we report that the lipid peroxidation end product 4-hydroxynonenal (HNE) significantly potentiates the anti-tumor effects of the HDAC inhibitor panobinostat (LBH589) in the PC3 prostate cancer cell model. Panobinostat and HNE inhibited proliferation of PC3 cells and the combination of the two agents resulted in a significant combined effect.
View Article and Find Full Text PDFReacytive Oxygen Species (ROS) have long been considered to be involved in the initiation, progression and metastasis of cancer. However, accumulating evidence points to the benefical role of ROS. Moreover, ROS production, leading to apoptosis, is the mechanism by which many chemotherapeutic agents can act.
View Article and Find Full Text PDFIn human cells the length of telomeres depends on telomerase activity. This activity and the expression of the catalytic subunit of human telomerase reverse transcriptase (hTERT) is strongly up-regulated in most human cancers. hTERT expression is regulated by different transcription factors, such as c-Myc, Mad1 and Sp1.
View Article and Find Full Text PDFJ Nutr Biochem
September 2010
The effects of polyunsaturated fatty acids (PUFAs) obtained from the diet on colorectal cancer have been widely explored. However, controversial results have been obtained about the role played by the lipid peroxidation products of PUFAs, such as 4-hydroxy-nonenal (HNE), in the control of colon cancer growth. This aldehyde, indeed, showed both procarcinogenic and protective effects.
View Article and Find Full Text PDFHNE (4-hydroxynonenal), the major product of lipoperoxidation, easily reacts with proteins through adduct formation between its three main functional groups and lysyl, histidyl and cysteinyl residues of proteins. HNE is considered to be an ultimate mediator of toxic effects elicited by oxidative stress. It can be detected in several patho-physiological conditions, in which it affects cellular processes by addition to functional proteins.
View Article and Find Full Text PDFTelomerase enzyme, containing a catalytic subunit, the human telomerase reverse transcriptase (hTERT), and a small integral RNA component, synthesises the telomeres, the ends of eukaryotic chromosomes. Inhibition of telomerase activity leads the cells to senescence and death. Myelodysplastic syndromes (MSD) are hematological malignancies characterized by peripheral blood cytopenia and ineffective hematopoiesis.
View Article and Find Full Text PDF4-Hydroxynonenal (HNE) is one of several lipid oxidation products that may have an impact on human pathophysiology. It is an important second messenger involved in the regulation of various cellular processes and exhibits antiproliferative and differentiative properties in various tumor cell lines. The mechanisms by which HNE affects cell growth and differentiation are only partially clarified.
View Article and Find Full Text PDFThe role of the Notch1 pathway has been well assessed in leukemia. Notch1 mutations are the most common ones in T acute lymphoblastic leukaemia patients which carry either oncogenic Notch1 forms or ineffective ubiquitin ligase implicated in Notch1 turnover. Abnormalities in the Notch1-Jagged1 system have been reported also in acute myelogenous leukaemia (AML) patients where Jagged1 is frequently over-expressed.
View Article and Find Full Text PDFPeroxisome proliferators-activated receptors (PPARs) are ligand-activated transcription factors that belong to the nuclear hormone receptor superfamily. The three PPAR isoforms (alpha, gamma and beta/delta) have been found to play a pleiotropic role in cell fat metabolism. Furthermore, in recent years, evidence has been found regarding the antiproliferative, proapoptotic, and differentiation-promoting activities displayed by PPAR ligands, particularly by PPARgamma ligands.
View Article and Find Full Text PDFIn recent years, it has become evident that lipid peroxidation is not only a mechanism for deterioration of alimentary oils and fats, but can occur even in living cells, both in pathological and physiological conditions. Through its aldehydic products, it can regulate several cellular processes, as proliferation, differentiation and apoptosis of normal and neoplastic cells. In this review we describe some recent findings obtained in these fields.
View Article and Find Full Text PDFPPARgamma ligands inhibit growth and induce apoptosis of various cancer cells. 4-Hydroxynonenal (HNE), a product of lipid peroxidation, inhibits proliferation and induces differentiation or apoptosis in neoplastic cells. The aim of this work was to investigate the effects of PPARgamma ligands (rosiglitazone and 15-deoxy-prostaglandin J2 (15d-PGJ2)) and HNE, alone or in association, on proliferation, apoptosis, differentiation, and growth-related and apoptosis-related gene expression in colon cancer cells (CaCo-2 cells).
View Article and Find Full Text PDF4-Hydroxynonenal (HNE), produced during oxidative stress, has an antiproliferative/differentiative effect in several tumor cells. Recently, it has been observed that oxidative stress accelerates telomere loss. The length of telomeres depends on the telomerase activity, and the catalytic subunit of telomerase (hTERT) is strongly up-regulated in most human cancers and inhibited by differentiating agents.
View Article and Find Full Text PDFLipid peroxidation is very low in proliferating cells and tumours and it might have a role in the regulation of cell proliferation and differentiation by acting through its products. 4-hydroxynonenal (HNE) has been proposed as a mediator of lipoperoxidation effects. It has been demonstrated that HNE can inhibit cell growth and induce differentiation in different leukemic cell lines.
View Article and Find Full Text PDF4-Hydroxynonenal (HNE), a product of lipid peroxidation, inhibits proliferation of several tumor cells. The p53 tumor suppressor protein plays a critical role in cell cycle control, by inducing p21 expression, and in apoptosis, by inducing bax expression. Recently, two other proteins with many p53-like properties, TAp73 (p73) and TAp63 (p63), have been discovered.
View Article and Find Full Text PDFFree Radic Biol Med
September 2004
The hypothesis that 4-hydroxynonenal (HNE), a product of lipid peroxidation, might negatively affect cell proliferation, arose from the observation that lipid peroxidation is very low in tumors. In leukemic cells HNE inhibited cell growth and reduced c-myc and c-myb expression. HNE also induced differentiation in different leukemic cell lines.
View Article and Find Full Text PDFBackground/aims: 4-Hydroxynonenal (HNE) is a putative pro-fibrogenic product of oxidative stress able to elicit apoptosis and cytotoxicity in several cell types. This study has been performed to evaluate its 'in vivo' levels in injured liver and whether HNE may induce apoptosis and/or affect selected phenotypic responses in activated human hepatic stellate cells (HSC/MF).
Methods/results: During the development of acute liver injury induced by CCl(4), liver tissue HNE levels were in the range 0.
4-hydroxynonenal is a major product of lipid peroxidation. It was firstly studied under the point of view of its toxicity, as it is an easily diffusable substance, thought to be able to explain the "far damages" seen in conditions of increased lipid peroxidation. Really, when used at concentration from 10 microM to 1 mM, usually referred to as high concentrations, the aldehyde is able to produce strong inhibitions of several enzymatic activities.
View Article and Find Full Text PDFPeroxisome proliferator-activated receptors (PPARs) are ligand-activated nuclear receptors. Three subtypes of PPARs (alpha, beta, and gamma) have been identified in different tissues. PPAR alpha and PPAR gamma ligands inhibit cell proliferation and induce differentiation in several human cell models.
View Article and Find Full Text PDFOur work analysed the effect of 4-hydroxynonenal (HNE), a chemotactic aldehydic end-product of lipid peroxidation, on exocytosis in HL-60 cells. We measured the release of beta-glucuronidase, an enzyme of azurophil granules, from the cells incubated at 37 degrees C for 10 min in the presence of HNE concentrations ranging between 10(-8) and 10(-5) M. The release of lactate dehydrogenase was assayed to test cell viability.
View Article and Find Full Text PDF4-Hydroxynonenal (HNE), a highly reactive product of lipid peroxidation, has an antiproliferative effect in several tumor cell lines and provokes alteration of cell cycle progression in HL-60 cells. HNE down-regulates c-myc expression in K562, HL-60, and MEL cells. This prompted us to study the cascade of phenomena that, starting from the CKIs expression and the phosphorylation of pRb, arrives at the E2F binding to consensus sequence in the P2 promoter of the c-myc gene.
View Article and Find Full Text PDFPeroxisome proliferator-activated receptors play an important role in the differentiation of different cell lines. In this study we demonstrate that PPAR-alpha ligands (clofibrate and ciprofibrate) and PPAR-gamma ligands (troglitazone and 15d-prostaglandin J2) inhibit growth and induce monocytic differentiation in HL-60 cells, whereas only PPAR-gamma ligands inhibit growth of U937 cells. Differentiation was demonstrated by the analysis of surface antigen expression CD11b and CD14, and by the characteristic morphological changes.
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