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Early in the COVID-19 pandemic, it emerged that the risk of severe outcomes was greater in patients with co-morbidities, including cancer. The huge effort undertaken to fight the pandemic, affects the management of cancer care, influencing their outcome. Despite the high fatality rate of COVID-19 disease in cancer patients, rare cases of temporary or prolonged clinical remission from cancers after SARS-CoV-2 infection have been reported. We have reviewed sixteen case reports of COVID-19 disease with spontaneous cancer reduction of progression. Fourteen cases of remission following viral infections and two after anti-SARS-CoV-2 vaccination. The immune response to COVID-19, may be implicated in both tumor regression, and progression. Specifically, we discuss potential mechanisms which include oncolytic and priming hypotheses, that may have contributed to the cancer regression in these cases and could be useful for future options in cancer treatment.

Additional file 1: Suppl. Figure 1. P2X4 in clear cell renal carcinoma correlates with mitochondrial antioxidant proteins by mRNA seq data bases. Suppl. Figure 2. (A) Representative MRI image of a patient with kidney carcinoma. (B) Organoid diameters after different time of culture. Data represent 3 different measurements of 3-5 biological replicates. Scale bars = 50 μm (C) Representative hematoxylin-eosin (H&E) staining of different clear cell carcinomas biopsies together with the bright-field microscope images of corresponding H&E stained ccRCC organoids (inset). Scale bars = 50 μm. Suppl. Figure 3. (A) Representative image of organoids treated with DMSO vehicle or 5-BDBD for different times and then stained with Calcein-AM (green) indicating vital cells or PI (red) indicating necrotic ones. Scale bar = 100 µm. (B) Concentration response to 5-BDBD determined in 3D culture assay measured at day 10 yielding an IC50 value of 7.556 µM (C) Schematic representation of plate view software dosage of 5-BDBD tested on 20 replicates for individual dose in single patient analyzed by CELIGO software. (D) Comparison of organoids growth for 3 days than treated with DMSO or 5-BDBD (5µM) for additional 7 days. Scale bar 100µm (E) Colony formation assay. The number of colony formed by A-498 cells 105 per well in presence of Vehicle (DMSO) or 5-BDBD at 5μM were cultured for 14 days colonies were stained with crystal violet and then photographed. Suppl. Figure 4. (A) Phase contrast image of representative organoids from different patients (PDO#1-5) treated with different doses of Everolimus for 7 days. (B,C) Quantification by MTT assay of the vitality reported as ratio to non treated organoids x100 from different patients (PDO#1-5) treated for 7 days with increasing doses of Everolimus or EZD8055, as indicated. Data are means of 20 replicate organoids from the same patient for each dose. Error bars are SD of 29 biological replicated for each dose. Table 1. Clinical features of the Clear Cell Renal Carcinomas. Table 2. Imaging characteristics of renal lesions.

// Flavio Fazioli 1, * , Gianluca Colella 2, * , Roberta Miceli 3 , Mariano Giuseppe Di Salvatore 1 , Michele Gallo 1 , Serena Boccella 4 , Annarosaria De Chiara 5 , Carlo Ruosi 2, * and Filomena de Nigris 6, * 1 Division of Musculoskeletal Oncology Surgery, National Cancer Institute G. Pascale, Naples, Italy 2 Department of Human Health, Federico II University of Naples, Naples, Italy 3 S.C. Cellular Biology and Biotherapy, National Cancer Institute G. Pascale, Naples, Italy 4 Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, Naples Italy 5 Division of Pathology, National Cancer Institute G. Pascale Foundation, Naples, Italy 6 Department of Biochemistry, Biophysics and General Pathology, University of Campania “Luigi Vanvitelli”, Naples Italy * These authors have contributed equally to this work Correspondence to: Filomena de Nigris, email: Filomena.denigris@unina2.it Keywords: recurrences, sarcoma, angiogenesis, stem cells, AKT Received: March 31, 2017 Accepted: May 29, 2017 Published: June 28, 2017 ABSTRACT Giant cell tumors of bone (GCTB) are rare sarcomas with a high rate of unpredictable local relapse. Studies suggest that surgical methods affect recurrence, supporting the idea that local disease develops from re-growth of residual cancer cells. To identify early prognostic markers of individual risk of recurrence, we evaluated the effect of post-surgery fluids from a cohort of GCTB patients on growth of primary and established sarcoma cell lines, and mice xenograph. Post-surgery fluids increased cell growth and enhanced expression of CD44 ++ , the principal receptor for the extracellular matrix component hyaluronan and the mesenchymal stem marker CD117 + . Cancer cells became highly invasive and tumorigenic, acquiring stemness properties, and activated AKT/mTOR pathway. Prolonged stimulation with post-surgery fluids down-regulated the mesenchymal gene TWIST1 and Vimentin protein, and transdifferentiated cells into tubule-like structures positive to the endothelial markers VE-Cadherin and CD31 + . In mice, post-surgery fluids gave rise to larger and more vascularized tumors than control, while in patients AKT/mTOR pathway activation was associated with recurrence by logistic regression (Kaplan-Meier; P

Background Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cancer. Large-scale metabolomic data have associated metabolic alterations with the pathogenesis and progression of renal carcinoma and have correlated mitochondrial activity with poor survival in a subset of patients. The aim of this study was to determine whether targeting mitochondria-lysosome interaction could be a novel therapeutic approach using patient-derived organoids as avatar for drug response. Methods RNAseq data analysis and immunohistochemistry were used to show overexpression of Purinergic receptor 4 (P2XR4) in clear cell carcinomas. Seahorse experiments, immunofluorescence and fluorescence cell sorting were used to demonstrate that P2XR4 regulates mitochondrial activity and the balance of radical oxygen species. Pharmacological inhibitors and genetic silencing promoted lysosomal damage, calcium overload in mitochondria and cell death via both necrosis and apoptosis. Finally, we established patient-derived organoids and murine xenograft models to investigate the antitumor effect of P2XR4 inhibition using imaging drug screening, viability assay and immunohistochemistry. Results Our data suggest that oxo-phosphorylation is the main source of tumor-derived ATP in a subset of ccRCC cells expressing P2XR4, which exerts a critical impact on tumor energy metabolism and mitochondrial activity. Prolonged mitochondrial failure induced by pharmacological inhibition or P2XR4 silencing was associated with increased oxygen radical species, changes in mitochondrial permeability (i.e., opening of the transition pore complex, dissipation of membrane potential, and calcium overload). Interestingly, higher mitochondrial activity in patient derived organoids was associated with greater sensitivity to P2XR4 inhibition and tumor reduction in a xenograft model. Conclusion Overall, our results suggest that the perturbed balance between lysosomal integrity and mitochondrial activity induced by P2XR4 inhibition may represent a new therapeutic strategy for a subset of patients with renal carcinoma and that individualized organoids may be help to predict drug efficacy.

A great interest in the scientific community is focused on the improvement of the cure rate in patients with bone malignancies that have a poor response to the first line of therapies. Novel treatments currently include epigenetic compounds or molecules targeting epigenetic-sensitive pathways. Here, we offer an exhaustive review of such agents in these clinical settings. Carefully designed preclinical studies selected several epigenetic drugs, including inhibitors of DNA methyltransferase (DNMTIs), such as Decitabine, histone deacetylase classes I-II (HDACIs), as Entinostat, Belinostat, lysine-specific histone demethylase (LSD1), as INCB059872 or FT-2102 (Olutasidenib), inhibitors of isocitrate dehydrogenases, and enhancer of zeste homolog 2 (EZH2), such as EPZ6438 (Tazemetostat) To enhance the therapeutic effect, the prevalent approach in phase II trial is the association of these epigenetic drug inhibitors, with targeted therapy or immune checkpoint blockade. Optimization of drug dosing and regimens of Phase II trials may improve the clinical efficiency of such novel therapeutic approaches against these devastating cancers.

Understanding the mechanisms inducing endothelial cell (EC) proliferation following tumor microenvironment stimuli may be important for the development of antiangiogenic therapies. Here, we show that cyclin-dependent kinase 2 and 5 (Cdk2, Cdk5) are important mediators of neoangiogenesis in in vitro and in vivo systems. Furthermore, we demonstrate that a specific Yin Yang 1 (YY1) protein-dependent signal from osteosarcoma (SaOS) cells determines proliferation of human aortic endothelial cells (HAECs). Following tumor cell stimuli, HAECs overexpress Cdk2 and Cdk5, display increased Cdk2 activity, undergo enhanced proliferation, and form capillary-like structures. Moreover, Roscovitine, an inhibitor of Cdks, blunted overexpression of Cdk2 and Cdk5 and Cdk2 activity induced by the YY1-dependent signal secreted by SaOS cells. Furthermore, Roscovitine decreased HAEC proliferation and angiogenesis (the latter by 70% in in vitro and 50% in in vivo systems; P

PURPOSE: The pathogenic role of angiotensin-converting enzyme (ACE) inhibition in hypertensive patients regarding endothelial progenitor-cell (EPC) function is still poorly understood. The aim of the study was to evaluate EPC number, function, and relationship to carotid intima media thickness (IMT) progression. METHODS: We studied 36 newly diagnosed mildly hypertensive patients free of cardiovascular disease and related risk factors without prior or concurrent therapy with ACE inhibitors. Patients were randomized to receive enalapril 20 mg/day (n = 18) or zofenopril 30 mg/day (n = 18). EPC number and migrating capacity, plasma nitrite and nitrate (NOx), and isoprostane concentrations were evaluated. Carotid IMT was determined by ultrasonography at baseline and after 1 and 5 years of follow-up. RESULTS: EPC number increased during the follow-up, with no statistical differences between treatment groups. There was an inverse correlation between circulating EPCs and IMT increase over time. Plasma NOx decreased during the study without evident differences between treatment groups. Isoprostanes decreased more markedly in zofenopril-treated patients. Multiple linear regression model demonstrated that carotid IMT was significantly inversely correlated with EPC but not with migratory cells after adjusting for confounders. CONCLUSIONS: The study demonstrated that EPC levels increased during the follow-up in both groups of newly diagnosed hypertensive patients treated with ACE inhibitors. These drugs prevented progression of vascular damage, with an inverse correlation between circulating EPC levels and IMT values.

Background The custom microenvironment ‘vascular niche’ is a potential therapeutic target for several pathophysiological conditions. Osteoblasts regulate the hematopoietic stem cell niche, and activation of the parathyroid hormone (PTH) receptor can increase the number of cells mobilized into the bloodstream. Methods C57Bl/6 mice were randomly assigned treatment with granulocyte-colony stimulating factor (G-CSF), PTH, G-CSF plus PTH or saline. All mice underwent hindlimb ischemia. Blood flow was measured by laser Doppler imaging. Indices of capillary activity were determined by electron microscopy in muscle tissue. CD34+ and Ki67+ cells were detected and evaluated by immunofluorescence, apoptosis by TUNEL, surface antigen and endothelial progenitor cells by fluorescence-activated cell sorting analysis, and vascular endothelial growth factor-164 and angiopoietin-1 expression by reverse-transcriptase polymerase chain reaction. Frozen bone marrow sections were stained for antigen-specific B cells and fibronectin and analyzed by confocal laser scanning microscopy. Results Following mobilization induced by G-CSF treatment, mice also treated with PTH showed increases in blood flow, capillary density, nitrite/nitrate release, angiogenic factors and circulating progenitor cells, as well as reduced apoptosis, fibrosis, oxidative stress and inflammation in ischemic muscles. Furthermore, hematopoietic antigen-specific B cells in the bone marrow were also increased by G-CSF alone and in combination with PTH. Conclusions PTH might increase the efficiency of hematopoietic stem-cell-based therapy in a recognized model of peripheral ischemia. Our translational experimental therapeutic targeting of the vascular niche points to novel clinical targets for the hematopoietic stem-cell treatment of ischemic vascular diseases.

Peripheral arterial disease (PAD) is a major health problem, especially when associated with severe hypertension. Administration of autologous bone marrow cells (BMCs) is emerging as a novel intervention to induce neoangiogenesis in ischemic limb models and in patients with PAD. This study evaluates the neovascularization capacity of BMCs alone or in combination with metabolic cotreatment (0.8% vitamin E, 0.05% vitamin C, and 5% of L-arginine) in a rat model of ischemic hindlimbs of spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY). Molecular mechanisms were investigated in bone marrow-derived endothelial progenitor cells (BM-EPC) derived from rats. BMC therapy increased blood flow and capillary densities and Ki67 proliferative marker, and it decreased interstitial fibrosis. These effects were amplified by metabolic cotreatment, an intervention that induces vascular protection at least partly through the nitric oxide (NO)/endothelial nitric oxide synthase (eNOS) pathway, reduction of systemic oxidative stress, and macrophage activation. In addition, BMC therapy alone and, more consistently, in combination with metabolic treatment, ameliorated BM-EPC functional activity via decreased cellular senescence and improved homing capacity by increasing CXCR4-expression levels. These data suggest potential therapeutic effects of autologous BMCs and metabolic treatment in hypertensive PAD patients.

Osteosarcoma is the most common primary malignant bone tumour in children and adolescents.1–3 Although osteosarcoma is primarily a disease of adolescents and young adults, a different type of osteosarcoma linked to Paget’s disease occurs in older adults. The outcome for patients with osteosarcomas is poor with a 2-year overall survival rate of 15–20% following surgical resection, chemotherapy and radiotherapy.2,4,5 The most frequent site for metastasis is the lung.6 However, metastasis can also occur in other bones and soft tissue.6–9 Death fromosteosarcoma is usually the result of progressive pulmonary metastasis with respiratory failure due to widespread disease.1,10,11 Increasing the understanding of the basic biology of osteosarcoma is a priority for tumour prognosis as well as for providing indications of possible tumour targets for selective therapy. The transcription factor Yin Yang 1 (YY1) is a multifunctional DNA binding protein and an ubiquitously expressed member of a polycomb group of proteins.12–14 The transcription factor YY1 is known to be present in some human cancer cell lines and its expression correlates to immune-mediated apoptosis.15–20 Here, we demonstrate for the first time that the transcription factor YY1 is selectively expressed in human osteosarcoma cells and biopsies. The RT-PCR analysis confirmed the data obtained with immunohistochemistry. 0959-8049/$

We show that human osteosarcoma cells (Saos-2) have downregulation of alpha3beta1-integrin compared to normal bone cells; this was further described in human osteosarcomas and in a primary murine sarcoma. The alpha3 gene was silenced in Saos-2 cells causing a low expression of alpha3beta1-integrin and reduction in collagen attachment with increasing migratory capacity. Chromatin immunoprecipitation assay performed on alpha3 promoter established that Myc and Yin Yang protein (YY1) cooperate in tandem to downregulate the alpha3 gene. This silencing mechanism involves the binding of Myc and YY1 to DNA and formation of complexes among Myc/Max, YY1, CREB-binding protein and deacetylation activity. The promoter containing deletions of E-boxes or YY1 cassettes failed to downregulate the transcription of a reporter gene as well as the inhibition of deacetylation activity. Overexpression of both Myc and YY1 was necessary to determine the alpha3-integrin promoter downregulation in normal osteoblasts. This downregulation of alpha3beta1-integrin can contribute to the acquisition of a more aggressive phenotype. YY1 regulated negatively the Myc activity through a direct interaction with the Myc/Max and deacetylase complexes. This represents a novel silencing mechanism with broad implications in the transcription machinery of tumours.

Apoptosis of arterial cells induced by oxidized low-density lipoprotein (oxLDL) is thought to contribute to the progression of vascular dysfunction and atherogenesis. It is well established that diabetes mellitus is accompanied by both glycosylation and oxidation LDL, but the biological effects of these modified lipoproteins are poorly understood. We demonstrate here that glycosylated oxLDL (glc-oxLDL) promotes apoptotic signaling in human coronary smooth muscle cells. This was associated by a decrease of the antiapoptotic protein Bcl-2, an increase of the pro-apoptotic protein Bax, and activation of caspase 3. Glc-oxLDL also activated NFK: B and decreased IK: B, these effects were more pronounced than those achieved with oxLDL. Our study shows that glc-oxLDL influences a broad cascade of signaling transduction pathways, which may not only result in apoptosis, but also could affect NFkappaB in human coronary cells. This cascade of events may influence the evolution of atherogenesis and vascular complications in diabetic patients.

Atherosclerosis is enhanced in arterial segments exposed to disturbed flow. Perturbed shear stress increases the expression of oxidation-sensitive responsive genes (such as ELK-1 and p -JUN) in the endothelium. Evidence suggests that polyphenolic antioxidants contained in the juice derived from the pomegranate can contribute to the reduction of oxidative stress and atherogenesis. The aim of the present study was to evaluate the effects of intervention with pomegranate juice (PJ) on oxidation-sensitive genes and endothelial NO synthase (eNOS) expression induced by high shear stress in vitro and in vivo . Cultured human coronary artery endothelial cells (EC) exposed to high shear stress in vitro and hypercholesterolemic mice were used in this study. PJ concentrate reduced the activation of redox-sensitive genes (ELK-1 and p -JUN) and increased eNOS expression (which was decreased by perturbed shear stress) in cultured EC and in atherosclerosis-prone areas of hypercholesterolemic mice. Moreover, oral administration of PJ to hypercholesterolemic mice at various stages of disease reduced significantly the progression of atherosclerosis. This experimental study indicates that the proatherogenic effects induced by perturbed shear stress can be reversed by chronic administration of PJ. This approach may have implications for the prevention or treatment of atherosclerosis and its clinical manifestations.

The pathogenic mechanisms by which physical exercise influences atherosclerotic lesion formation remain poorly understood. Because vigorous physical training increases oxidative stress, this study tested the hypothesis that graduated and moderate physical exercise together with metabolic intervention ( l -arginine and antioxidants) may contribute to increased vascular protection. Exercise training in mice was induced by graduated swimming. In hypercholesterolemic male mice on an atherogenic high-cholesterol diet, graduated and moderate exercise lowered plasma cholesterol and decreased atherosclerotic lesions compared with sedentary control mice. Antioxidants (1.0% vitamin E added to the chow and 0.05% vitamin C added to the drinking water) and l -arginine (6% in drinking water) supplementation to exercising hypercholesterolemic mice further and synergistically reduced atherosclerosis compared with untreated exercised mice. Arterial oxidation-specific epitopes and systemic oxidative stress were reduced by metabolic intervention. Graduated chronic exercise elicited an increase in production of nitric oxide through increased endothelial nitric oxide synthase expression and ameliorated scavenger activities. Thus, metabolic intervention with l -arginine and antioxidants together with graduated and moderate exercise training reduce atherosclerotic lesion formation.

We used subtractive library screening to identify the changes that occur in gene expression during thyroid cell neoplastic transformation. Complementary DNA from normal thyroid cells (HTC 2) was subtracted from a complementary DNA library constructed from a human thyroid papillary carcinoma cell line. The library was screened for genes upregulated in human thyroid papillary carcinoma cell line cells, and several cDNA clones were isolated. One of these clones has a sirtuin core and high homology with the human silent information regulator protein family. This clone, designated ‘SIR-T8’, was overexpressed in human thyroid carcinoma cell lines and tissues, but not in adenomas. The human SIR-T8 protein has a molecular weight of 39 kDa and is primarily located in the cytoplasm under the nuclear membrane. The SIR-T8 gene is located on chromosome 17q25-1. British Journal of Cancer (2002) 86, 917–923. DOI: 10.1038/sj/bjc/6600156 www.bjcancer.com © 2002 Cancer Research UK

Restenosis after percutaneous transluminal coronary angioplasty is caused by neointimal hyperplasia, which involves impairment of nitric oxide (NO)-dependent pathways, and may be further exacerbated by a concomitant aging process. We compared the effects of NO-releasing-aspirin (NCX-4016) and aspirin (ASA) on experimental restenosis in both adult and elderly rats. Moreover, to ascertain the efficacy of NCX-4016 during vascular aging, we fully characterized the release of bioactive NO by the drug. Sprague–Dawley rats aged 6 and 24 months were treated with NO releasing-aspirin (55 mg/kg) or ASA (30 mg/kg) for 7 days before and 21 days after standard carotid balloon injury. Histological examination and immunohistochemical double-staining were used to evaluate restenosis. Plasma nitrite and nitrate and S -nitrosothiols were determined by a chemiluminescence-based assay. Electron spin resonance was used for determining nitrosylhemoglobin. Treatment of aged rats with NCX-4016 was associated with increased bioactive NO, compared with ASA. NO aspirin, but not ASA, reduced experimental restenosis in old rats, an effect associated with reduced vascular smooth muscle cell proliferation. NCX-4016, but not ASA, was well tolerated and virtually devoid of gastric damage in either adult or old rats. Thus, impairment of NO-dependent mechanisms may be involved in the development of restenosis in old rats. We suggest that an NCX-4016 derivative could be an effective drug in reducing restenosis, especially in the presence of aging and/or gastrointestinal damage.

The effects of chronic treatment with the new sulfhydryl angiotensin-converting enzyme (ACE)-inhibitor, zofenopril, in comparison with the classical sulfhydryl ACE-inhibitor captopril or enalapril or placebo on the development of atherosclerosis were determined in apolipoprotein-E knockout (apoE(-/-)) mice. Groups of 2-month-old male mice received either placebo (N=10), 0.05 mg/kg/day of zofenopril (N=10), 1 mg/kg/day of zofenopril (N=10), 5 mg/kg/day of captopril (N=10) or 0.5 mg/kg/day of enalapril (N=8). After 29 weeks of treatment, computer-assisted imaging analysis revealed that zofenopril reduced the aortic cumulative lesion area by 78% at 0.05 mg/kg/day and by 89% at 1 mg/ml/day of zofenopril compared to that of the placebo (P

Increased oxidative stress plays an important role in vascular dysfunction and atherogenesis. Both systemic factors, such as hypercholesterolemia and hyperglycemia, and local factors, such as activation of macrophages and T cells, may contribute to oxidative stress. Oxidation of lipids in lipoproteins and cell membranes leads to functionally important modifications of proteins that affect their recognition by cell surface receptors and protein-protein interactions within the cell, including DNA binding. Oxidized LDL and extracellular oxidation modulate oxidation-sensitive signaling pathways, but it is not clear to what extent this results from receptor-mediated activation or from direct effects on the intracellular redox-balance. Extensive evidence indicates that reactive oxygen species (ROS) regulate gene expression by modulating a large number of transcription factors, including the nuclear transcription factor kappa B (NFkappaB), the peroxisome proliferator activated receptorgamma (PPARgamma), and pathways linked to apoptosis. It is also increasingly recognized that cell differentiation and proliferation, cytokine expression, and programmed cell death are determined by the interactions between oxidation-sensitive regulatory pathways previously thought to lead to distinct outcomes. Because hypercholesterolemia exerts pro-oxidant effects both intra- and extracellularly and because increased ROS formation affects vascular reactivity and atherogenesis by modulating multiple signaling pathways and transcriptional events, future investigations of its atherogenic mechanisms should place greater emphasis on the net effect of such modulation on the expression of a large spectrum of genes. One way of doing this will be by defining clusters of genes responding to hypercholesterolemic stimuli--or interventions with structurally unrelated antioxidants--in analogous ways, irrespective of what regulatory pathway they are controlled by. Microarray technologies that allow simultaneous assessment of large numbers of genes may provide a tool for this approach.

Abstract —Maternal hypercholesterolemia during pregnancy is associated with a marked increase in aortic fatty streak formation in human fetuses and faster progression of atherosclerosis during normocholesterolemic childhood. However, the mechanisms responsible are unknown, and the contribution of genetic differences is difficult to assess in humans. The goal of this study was to determine whether maternal hypercholesterolemia per se may cause enhanced fatty streak formation in offspring and whether interventions during pregnancy can reduce it. During pregnancy, 1 group of New Zealand White rabbits was fed control chow and 8 groups were fed hypercholesterolemic diets Chol 1 (yielding plasma cholesterol of 153 mg/dL) or Chol 2 (yielding 359 mg/dL) without or with cholestyramine, vitamin E, or both. Offspring (n=15 to 25 per group) were killed at birth. Maternal hypercholesterolemia enhanced mean lesion size in the aorta of their offspring at birth from 44±18×10 3 μm 2 per section in controls to 85±26×10 3 in Chol 1 and 156±49×10 3 in Chol 2 groups ( P

The prodromal stage of atherosclerotic lesions (known as lipidotic fatty streak accumulation) is already formed during human fetal development.1 Fatty streaks containing characteristic accumulations of lipids, lipid peroxidation products, and macrophages occur in the aorta of premature fetuses. Intimal thickening is also observed in fetal coronary arteries.2,3 During infancy, fatty streaks become increasingly prevalent, and some of them progress to advanced stages of atherosclerotic lesions.4–7 Once initiated, the progression of atherosclerosis is influenced by classic risk factors that promote vascular inflammation and plaque rupture. The observation that maternal hypercholesterolemia is associated with greatly enhanced fatty streak formation in fetal arteries1 indicates that hypercholesterolemia may play a pathogenic role in early fetal atherosclerotic lesions. Maternal hypercholesterolemia is also able to influence fetal sterol metabolism during pregnancy in animal models.8,9 Consistently, direct evidence for a causal role of maternal hypercholesterolemia and the involvement of oxidative stress has been obtained in a rabbit model10,11 and in LDL receptor–deficient mice.12 From a molecular standpoint, many signaling pathways are affected by increased oxidation of LDL or the intracellular formation of reactive oxygen species, and this phenomenon can be exacerbated by concomitant hypercholesterolemia.13 Interestingly, deletion of the p66 shc longevity gene reduces systemic and tissue oxidative stress, vascular cell apoptosis, and early atherogenesis in mice fed a very highly hypercholesterolemic diet.14 Finally, growing evidence in the literature suggests that vascular damage occurs early and is mediated by …

Mediator complex (MED) is an evolutionarily conserved multiprotein, fundamental for growth and survival of all cells. In eukaryotes, the mRNA transcription is dependent on RNA polymerase II that is associated to various molecules like general transcription factors, MED subunits and chromatin regulators. To date, transcriptional machinery dysfunction has been shown to elicit broad effects on cell proliferation, development, differentiation, and pathologic disease induction, including cancer. Indeed, in malignant cells, the improper activation of specific genes is usually ascribed to aberrant transcription machinery. Here, we focus our attention on the correlation of MED subunits with carcinogenesis. To date, many subunits are mutated or display altered expression in human cancers. Particularly, the role of MED1, MED28, MED12, CDK8 and Cyclin C in cancer is well documented, although several studies have recently reported a possible association of other subunits with malignancy. Definitely, a major comprehension of the involvement of the whole complex in cancer may lead to the identification of MED subunits as novel diagnostic/prognostic tumour markers to be used in combination with imaging technique in clinical oncology, and to develop novel anti-cancer targets for molecular-targeted therapy. © 2013.

CXCL12, also known as SDF-1, is the single natural ligand for chemokine receptors CXCR4 and CXCR7. CXCL12 has angiogenic properties in normal endothelial tissue and is involved in the outgrowth and metastasis of CXCR4 expressing tumors. Recent investigations have indicated that CXCL12 levels increase after chemo- and anti- VEGF therapy, favouring recurrences. The blockade of CXCL12/CXCR4 axis has emerged as a potential additional or alternative target for neo-adjuvant treatments. We have reviewed recent patent applications between 2008 and 2011 in tumor angiogenesis and the most clinical data supporting the potential use of anti-CXCR4 agents in this field. Among these, AMD3100, also known as Plerixaform (Mozobil® by Genzyme), is approved for stem cell mobilisation in patients with leukaemia, while BKT140 (Emory University), POL6326 (Polyphor Ag) and TG-0054 (ChemoCentryx) are currently in clinical trials in combination with chemotherapy for multiple myeloma and leukaemia. The aptamer Nox-A12 (Noxxon) is in trials for chronic lymphatic leukaemia treatment. MSX-122 (Metastatix) is in Phase I trials for solid tumor treatment, while CXCR7-specific inhibitor CCX2066 (ChemoCentryx) is still in preclinical studies. We have also considered other strategies, such RNA interference and miRNA, which could be tested for solid tumor adjuvant therapy.

Targeting neoangiogenesis is a well-established anticancer strategy, however, one of the major problems in angiogenesis research, both at the basic and applied levels, remains the development of suitable in vivo methods for assessing and quantifying the systemic angiogenic response. Therefore, there is an urgent need to adopt technically simple and reproducible methodologies which allow to easily quantify neoangiogenesis independently of morphological parameters. Recently, a reproducible and quantitative method was developed, the directed in vivo angiogenesis assay (DIVAA) consisting of the subcutaneous implantation of surgical grade silicone cylinders closed at one end, called angioreactors, into the dorsal flanks of nude mice. In the past few years, DIVAA has been successfully used in evaluating the inhibition and or enhancement of systemic perturbation of angiogenesis by several molecules. Thus, DIVAA studies systemic angiogenesis and its therapeutic modulation associated to cancer progression and metastasis.

Tumor growth requires neoangiogenesis. VEGF is the most potent proangiogenic factor. Dysregulation of hypoxia-inducible factor (HIF) or cytokine stimuli such as those involving the chemokine receptor 4/stromal-derived cell factor 1 (CXCR4/SDF-1) axis are the major cause of ectopic overexpression of VEGF in tumors. Although the CXCR4/SDF-1 pathway is well characterized, the transcription factors executing the effector function of this signaling are poorly understood. The multifunctional Yin Yang 1 (YY1) protein is highly expressed in different types of cancers and may regulate some cancer-related genes. The network involving CXCR4/YY1 and neoangiogenesis could play a major role in cancer progression. In this study we have shown that YY1 forms an active complex with HIF-1α at VEGF gene promoters and increases VEGF transcription and expression observed by RT-PCR, ELISA, and Western blot using two different antibodies against VEGFB. Long-term treatment with T22 peptide (a CXCR4/SDF-1 inhibitor) and YY1 silencing can reduce in vivo systemic neoangiogenesis ( P < 0.01 and P < 0.05 vs. control, respectively) during metastasis. Moreover, using an in vitro angiogenesis assay, we observed that YY1 silencing led to a 60% reduction in branches ( P < 0.01) and tube length ( P < 0.02) and a 75% reduction in tube area ( P < 0.001) compared with control cells. A similar reduction was observed using T22 peptide. We demonstrated that T22 peptide determines YY1 cytoplasmic accumulation by reducing its phosphorylation via down-regulation of AKT, identifying a crosstalk mechanism involving CXCR4/YY1. Thus, YY1 may represent a crucial molecular target for antiangiogenic therapy during cancer progression.

We know that the Yin Yang 1 protein (YY1) overexpression is positively and strongly correlated with the degree of malignancy of bone tumors. Therefore, we questioned whether we could influence cell invasiveness by deleting YY1 in human osteosarcoma cells (SaOs-2), as tested in Matrigel-coated filters and metastasis implantation of such osteosarcoma cells in vivo, by serial analysis with nuclear magnetic resonance. Moreover, we focused our work on the chemokine receptor CXCR4 and its inhibition by T22 antibody, as well as on systemic (direct in vivo assay) and computer-assisted imaging of angiogenesis-related metastasis. Results showed that cell invasiveness and metastasis implantation by wild-type SaOs-2 cells, as evaluated by histology and immunohistochemistry, are associated with up-regulation of CXCR4 expression, which in turn was significantly reduced by T22. In addition, deletion of YY1 (siRNAYY1-SaOs-2) induced a significant decrease of cell invasion and metastasis growth. This phenomenon was associated with decreased vascular endothelial growth factor (VEGF)/angiogenesis and a complex rearrangement of the gene expression profile as evaluated by microarray analysis. In conclusion, YY1 and VEGF/CXCR4 seem to intervene in the pathogenesis of the malignant phenotype of osteosarcoma by acting on cell invasiveness and metastasis growth. [Cancer Res 2008;68(6):1797–808]

Previous studies showed that p66(Shc-/-) mice on a very-high-fat diet (HFD) had reduced oxidative stress, foam cell, and early atherosclerotic lesion formation. Here, the authors have used hypercholesterolemic apolipoprotein E (ApoE(-/-)) mice to investigate the role of p66Shc deletion in advanced atheroma. The authors generated mice deficient of both ApoE and p66Shc genes (ApoE(-/-) /p66(Shc-/-)). They used microsatellite polymerase chain reaction (PCR) analysis to analyze the genetic background and considered only animals with a constant percentages of C57B6L and 129SV background strands (it was obtained the 50.3% +/- 6.4% of C57B6L background). Computer-assisted analysis revealed that advanced atherosclerotic lesions in ApoE(-/-)/p66(Shc+/+) were significantly larger than those observed in ApoE(-/-)/p66(Shc-/-). Accordingly, the lipid-laden macrophage foam cells and oxidation-specific epitopes in ApoE(-/-)/p66(shc+/+) HFD-treated groups were higher than those observed in normal diet (ND)-treated groups. Thus, p66(Shc-/-) plays an important protective role also against advanced atherosclerotic lesion formation. Finally, the authors have used microarray to investigate major changes in gene expression in aortas of mice with ApoE(-/-)/p66(Shc-/-) background treated with a very HFD in comparison to ApoE(-/-)/p66(Shc+/+) (these data have been confirmed by by real-time PCR and immunohistochemistry). DAVID (Database for Annotation, Visualization and Integrated Discovery) analysis revealed that CD36 antigen (CD36), tissue inhibitor of metalloproteinase 2 (TIMP2), apolipoprotein E (ApoE), acetyl-coenzyme A acetyltransferase 1 (ACAT1), and thrombospondin 1 (THBS1) can be involved in p66 deletion-dependent vascular protection through the adipocytokine/lipid signaling pathway.

Despite advances in imaging, understanding the underlying pathways, and clinical translation of animal models of disease there remains an urgent need for therapies that reduce brain damage after stroke and promote functional recovery in patients. Blocking oxidant radicals, reducing matrix metalloproteinase-induced neuronal damage, and use of stem cell therapy have been proposed and tested individually in prior studies. Here we provide a comprehensive integrative management approach to reducing damage and promoting recovery by combining biological therapies targeting these areas. In a rat model of transient cerebral ischemia (middle cerebral artery occlusion) gene delivery vectors were used to overexpress tissue inhibitor of matrix metalloproteinase 1 and 2 (TIMP1 and TIMP2) 3 days before ischemia. After occlusion, autologous bone marrow cells alone or in combination with agents to improve NO bioavailability were administered intraarterially. When infarct size, BrdU incorporation, and motor function recovery were determined in the treatment groups the largest beneficial effect was seen in rats receiving the triple combined therapy, surpassing effects of single or double therapies. Our study highlights the utility of combined drug, gene, and cell therapy in the treatment of stroke. © 2007 by The National Academy of Sciences of the USA.

Metabolic syndrome includes most widely distributed clinical conditions such as obesity, hypertension, dislipidemia, and diabetes. Pomegranate fruit extract (PFE), rich in polyphenolic antioxidants, reduces the expression of oxidation-sensitive genes at the sites of perturbed shear-stress. The aim of this study was to evaluate the effect of PFE in comparison to regular pomegranate juice (PJ) and seed oil on the biological actions of nitric oxide (NO) and the arterial function in obese Zucker rats, a model of metabolic syndrome. Our results indicated that supplementation with PFE or PJ significantly decreased the expression of vascular inflammation markers, thrombospondin (TSP), and cytokine TGFbeta1 (P

Peripheral arterial disease (PAD) is a major health problem especially when associated to diabetes. Administration of autologous bone marrow cells (BMC) is emerging as a novel intervention to induce therapeutic angiogenesis in experimental ischemic limb models and in patients with PAD. Since tissue ischemia and diabetes are associated with an overwhelming generation of oxygen radicals and detrimental effects due to formation of glycosylation end-products, metabolic intervention with antioxidants and L-arginine can confer beneficial effects beyond those achieved by BMC alone. The effects of cotreatment with intravenous BMCs and metabolic vascular protection (1.0% vitamin E, 0.05% vitamin C, and 6% L-arginine) were examined in the ischemic hindlimb of diabetic and non diabetic mice. BMC therapy increased blood flow and capillary densities and Ki67 proliferative marker, and decreased interstitial fibrosis. This effect was amplified by metabolic cotreatment, an intervention inducing vascular protection, at least in part, through the nitric oxide pathway, reduction of systemic oxidative stress, and macrophage activation.

Cancer and vascular diseases remain the predominant causes of morbidity and mortality in industrialized countries worldwide. The course of atherosclerosis with initiation, progression, and complication parallels the three stages of carcinogenesis with induction, growth, and invasion of tissue and neoangiogenesis. Within this framework, the oncogene c-Myc and growth factors pathways are acquiring increasing importance. Insulin-like growth factor-1 (IGF-1) pathway emerges among them for its versatile pleiotropic actions. A number of genes that permit extensive communication between IGF-1-AKT, p53, and mammalian target of rapamycin (mTOR) pathways have been identified. In turn these pathways lead to p53 transcriptional program, the forkhead transcriptional programs, autophagy, and translational controls, which determine cell growth or arrest, cell survival or death. The increased understanding of the extensive communication and coordination between all these pathways may enable to targeting these events and to prevent neoplastic and vascular diseases. Great effort has been focused on the development of new agents designed to target various steps of c-Myc, Ras, and IGF cascade. However, what have we recently learned about their safety and effectiveness? Here, we review the very recent advances in the identification of novel inhibitors as well as antisense oligonuleotides (ASOs) and siRNA that are proving their usefulness in ongoing clinical trials both in terms of toxicity and specificity.

New approaches to atherosclerosis-related diseases include novel uses of proven treatments and development of innovative agents. Several commonly used cardiovascular drugs such as dihydropyridine calcium antagonists, ACE inhibitors containing the sulphydryl group, or highly lipophilic beta-blockers have some anti-atherosclerotic activities. Moreover, new clinical trials suggesting that additional reduction of low-density lipoprotein cholesterol levels with statin therapy results in additional benefit in coronary heart disease prevention. Notably, new cholesterol transport or bile acid transport inhibitors have been found to produce significant reductions in intestinal cholesterol absorption and experimental atherosclerosis. Inhibitors of acyl coenzyme A:cholesterol acyltransferase, which can reduce cholesterol storage in macrophages and in arterial lesions, have also been developed. Finally, newer therapeutical strategies against atherogenesis may include the use of antioxidants and cholestyramine during pregnancy or the development of metalloproteinase inhibitors.

AIM: To investigate protease activated receptor 2 (PAR-2) expression in human coronary atherosclerotic lesions because PAR-2 is involved in the modulation of inflammatory events and vascular function. METHODS: An immunohistochemical analysis was performed on serial arterial sections, using the following antibodies: MDA2, a murine monoclonal antibody against malondialdehyde lysine epitopes of oxidised low density lipoprotein (oxLDL); HAM-56, a monoclonal antibody against human macrophages/foam cells; B5, a rabbit polyclonal antibody against PAR-2; and SAM11, a mouse monoclonal antibody against human PAR-2. Sections containing at least one lesion showing substantial immunostaining were counted as positive, and results were expressed as per cent of all sections of the same artery. RESULTS: PAR-2 expression was enhanced in human coronary atherosclerotic lesions. This phenomenon correlated with an increase in oxLDL epitopes in the coronary artery. CONCLUSION: This study shows for the first time that PAR-2 expression is enhanced in human coronary atherosclerotic lesions, and suggests that PAR-2 dependent cellular trafficking may be one of the regulatory signalling responses to vascular injury. Further pharmacological studies will establish whether modulation (and in which direction) of PAR-2 represents a possible therapeutic target for controlling the vascular response to injury.

Atherogenesis is enhanced in arterial segments exposed to disturbed blood flow, indicating the active participation of the hemodynamic environment in lesion formation. Turbulent shear stress selectively regulates responsive genes in the endothelium and increases the damage induced by free radicals. The purpose of the present study was to evaluate the effects of intervention with antioxidants and l -arginine on endothelial NO synthase (eNOS) and oxidation-sensitive gene perturbation induced by disturbed flow in vitro and in vivo . Both human endothelial cells exposed to shear stress and high atherosclerosis-prone areas of hypercholesterolemic low-density lipoprotein receptor knockout (LDLR −/− ) mice showed increased activities of redox-transcription factors (ELK-1, p -Jun, and p -CREB) and decreased expression of eNOS. Intervention with antioxidants and l -arginine reduced the activation of redox-transcription factors and increased eNOS expression in cells and in vivo . These results demonstrate that atherogenic effects induced by turbulent shear stress can be prevented by cotreatment with antioxidants and l -arginine. The therapeutic possibility to modulate shear stress-response genes may have important implications for the prevention of atherosclerosis and its clinical manifestations.

Several experimental and clinical studies have shown that oxidized low-density lipoprotein and oxidation-sensitive mechanisms are central in the pathogenesis of vascular dysfunction and atherogenesis. Here, we have used p66 Shc−/− and WT mice to investigate the effects of high-fat diet on both systemic and tissue oxidative stress and the development of early vascular lesions. To date, the p66 Shc−/− mouse is the unique genetic model of increased resistance to oxidative stress and prolonged life span in mammals. Computer-assisted image analysis revealed that chronic 21% high-fat treatment increased the aortic cumulative early lesion area by ≈21% in WT mice and only by 3% in p66 Shc−/− mice. Early lesions from p66 Shc−/− mice had less content of macrophage-derived foam cells and apoptotic vascular cells, in comparison to the WT. Furthermore, in p66 Shc−/− mice, but not WT mice, we found a significant reduction of systemic and tissue oxidative stress (assessed by isoprostanes, plasma low-density lipoprotein oxidizability, and the formation of arterial oxidation-specific epitopes). These results support the concept that p66 Shc−/− may play a pivotal role in controlling systemic oxidative stress and vascular diseases. Therefore, p66 Shc might represent a molecular target for therapies against vascular diseases.

Apoptosis of arterial cells induced by oxidized low-density lipoprotein (oxLDL) is thought to contribute to the progression of vascular dysfunction and atherogenesis. It is well established that diabetes mellitus is accompanied by both glycosylation and oxidation of LDL (glc-oxLDL), but the biological effects of these modified lipoproteins are poorly understood. We demonstrate here for the first time that glc-oxLDL increases TUNEL positivity and caspase-3 activation (by Western blot and immunocytochemistry) of human coronary smooth muscle cells. Overall, these effects induced by glc-oxLDL were greater than those achieved with oxLDL. Thus, glc-oxLDL activated downstream apoptotic signaling. This may influence the evolution of atherogenesis and vascular complications in diabetes.

Background — Maternal hypercholesterolemia during pregnancy is associated with markedly enhanced fatty streak formation in human fetal aortas and accelerated progression of atherosclerosis in normocholesterolemic children. Methods and Results — To establish the causal role of maternal hypercholesterolemia in a genetically homogeneous murine model and to test the hypothesis that pathogenic events during fetal development result in persistent changes in arterial gene expression, female LDL receptor-deficient (LDLR −/− ) mice were fed regular chow or high-fat diets supplemented with 0.075% or 1.25% cholesterol during pregnancy. Lesion sizes were determined in the aortic origin of their chow-fed offspring at 3 months. Maternal hypercholesterolemia more than doubled lesion sizes in male offspring ( P 1.7-fold. Quantitative PCR for one of these genes using RNA from individual mice yielded similar results. Comparative immunostaining for several of the above genes also indicated increased protein content in offspring of hypercholesterolemic mothers. Conclusions — These findings establish an atherogenic effect of maternal hypercholesterolemia in genetically uniform mice and indicate that changes in aortic gene expression persist long after fetal exposure to hypercholesterolemia. In addition to elucidating pathogenic mechanisms initiated during fetal development, this approach may identify genes in morphologically normal arteries that influence the susceptibility to classical risk factors of atherosclerosis.

The effects of chronic treatment with nitric oxide-containing aspirin (NO-aspirin, NCX-4016) in comparison with regular aspirin or placebo on the development of a chronic disease such as atherosclerosis were investigated in hypercholesterolemic low-density lipoprotein (LDL)-receptor-deficient mice. Male mice were assigned randomly to receive in a volume of 10 ml/kg either placebo ( n = 10), 30 mg/kg/day NO-aspirin ( n = 10), or 18 mg/kg/day of regular aspirin ( n = 10). After 12 weeks of treatment, the computer-assisted imaging analysis revealed that NO-aspirin reduced the aortic cumulative lesion area by 39.8 ± 12.3% compared with that of the placebo ( P < 0.001). Regular aspirin did not reduce significantly aortic lesions (−5.1 ± 2.3%) compared with the placebo [ P = 0.867, not significant (NS)]. Furthermore, NO-aspirin reduced significantly plasma LDL oxidation compared with aspirin and placebo, as shown by the significant reduction of malondialdehyde content ( P < 0.001) as well as by the prolongation of lag-time ( P < 0.01). Similarly, systemic oxidative stress, measured by plasma isoprostanes, was significantly reduced by treatment with NCX-4016 ( P < 0.05). More importantly, mice treated with NO-aspirin revealed by immunohistochemical analysis of aortic serial sections a significant decrease in the intimal presence of oxidation-specific epitopes of oxLDL (E06 monoclonal antibody, P < 0.01), and macrophages–derived foam cells (F4/80 monoclonal antibody, P < 0.05), compared with placebo or aspirin. These data indicate that enhanced NO release by chronic treatment with the NO-containing aspirin has antiatherosclerotic and antioxidant effects in the arterial wall of hypercholesterolemic mice.

Background and purposeAtherosclerosis occurs later and is less extensive in intracranial arteries than in extracranial arteries. However, the mechanisms responsible are poorly understood. A previous study has suggested a better antioxidant protection of intracranial arteries.MethodsTo assess the influence of age on arterial activity of antioxidant enzymes and atherogenesis, we compared intracranial and extracranial arteries of humans of different ages who retrospectively lacked confounding classic risk factors (48 premature fetuses aged 6.4+/-0.8 months [mean+/-SD], 58 children aged 7.9+/-3.8 years, 42 adults aged 42.5+/-5.1 years, and 40 elderly subjects aged 71.8+/-3.4 years; all males). Lesions were quantified by computer-assisted imaging analysis of sections of the middle cerebral and basilar arteries, the left anterior descending coronary artery, the common carotid artery, and the abdominal aorta. Macrophages, apolipoprotein B, oxidized LDL, and matrix metalloproteinase-9 in lesions were determined by immunocytochemistry. The effect of aging on atherogenesis was then compared with that on the activity of 4 antioxidant enzymes in the arterial wall.ResultsAtherosclerosis was 6- to 19-fold greater (P

The proteins of the Ets family are transcription factors involved in signal transduction, cell cycle progression, and differentiation. In this study, we report that thyroid cell neoplastic transformation is associated with a dramatic increase in ETS transcriptional activity, which is dependent on the accumulation of Ets-1, Ets-2, and other Ets-related proteins. Inhibition of ETS transactivation activity by the Ets-dominant negative construct (Ets-Z) induced programmed cell death in human thyroid carcinoma cell lines but not in normal thyroid cells. Apoptotic cell death induced by Ets-Z was dependent on the reduction of c-MYC protein levels, because it was prevented by overexpressinn of c-myc. Taken together, these data indicate that the induction of Ets-l and Ets-2 transcription factors plays a pivotal role in thyroid cell neoplastic transformation.

This study tested the hypothesis that c-Myc activation, an oxidation-sensitive transcription factor, and its binding partner Max occurs in coronary arteries of hypercholesterolemic (HC) pigs, and can be attenuated by chronic antioxidant intervention. Coronary arteries were isolated from normal, HC pigs, or HC supplemented with antioxidant vitamins (HC + vitamins). The expression of the c-Myc/Max complex, and its target genes GADD45 and p53, was studied in nonatherosclerotic, early lesions (LL), positively staining for oil-red-O, in adjacent lesion-prone regions (PL), and in healthy segments (HV). The expression of c-Myc and Max in HC was 2- to 3-fold greater in PL, and 4-fold in LL, compared to normal vessels (P < 0.01). The expression of GADD45 was down-regulated, and of p53 increased, in the same regions. These alterations were attenuated in the HC + vitamins. Thus, c-Myc activation is an early atherosclerosis, in both PL and LL coronary arterial regions, and can be blunted by chronic dietary antioxidant intervention.

Apoptosis may play an important role in atherogenesis. Oxidized low-density lipoprotein (oxLDL) promotes apoptosis in the arterial wall in addition to several other proatherogenic effects. Tocopherol supplements have been suggested to protect against coronary heart disease (CHD) in epidemiological studies. The effects of oxLDL and alpha- and gamma-tocopherol on apoptotic signaling pathways are poorly understood. Thus, the goal of the study was to investigate these pathways in the presence of copper-oxidized LDL and tocopherols in human coronary smooth muscle cells (SMC). We showed that oxLDL-mediated apoptosis, assessed by DNA fragmentation, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, and caspase activation stimulated several transcription factors and proapoptotic dynamic movements of the Bcl-2 family proteins through the mitogen-activated protein kinase (MAPK) and Jun kinase pathways. alpha-Tocopherol and gamma-tocopherol significantly reduced these molecular events and cell death effectors caspase-3 and -8. Under our experimental conditions, alpha-tocopherol was significantly more effective than gamma-tocopherol, and oxLDL-mediated apoptosis increased c-Jun, cyclic AMP-responsive element-binding, Ets-like element kinase-dependent 7, and activating transcription factor-2 proteins as well as nuclear activity of the activated protein-1 complex in human coronary SMC. Moreover, our results demonstrate that tocopherols may exert their antiatherogenic effects at least in part via reduction of the MAPK and JunK cascade together with a protective profile of apoptotic genes of the Bcl-2 family. These data are consistent with the beneficial effects of tocopherols on atherogenesis seen in experimental studies and on CHD in epidemiological surveys.

Background —Oxidized LDL (oxLDL) promotes atherogenesis, and antioxidants reduce lesions in experimental models. OxLDL-mediated effects on c-Myc are poorly characterized, and those on c-Myc nuclear pathways are completely unknown. c-Myc stimulates smooth muscle cell (SMC) proliferation and could be involved in atherosclerosis. We investigated the early effects of oxLDL and α-tocopherol on c-Myc, its binding partner Max, and the carboxy-terminal domain–binding factors activator protein-2 and elongation 2 factor in human coronary SMCs. We also investigated whether 9-week treatment of Watanabe heritable hyperlipidemic (WHHL) rabbits with diet-enriched α-tocopherol reduces c-Myc expression and oxLDL in the left coronary artery. Methods and Results —OxLDL enhanced c-Myc/Max expression and transcription by cotransfection assay and the nuclear activities of E2F and activator protein-2 by binding shift and supershift in coronary SMCs. α-Tocopherol significantly reduced these molecular events. Furthermore, α-tocopherol reduced early lesions, SMC density, and the immunohistochemical presence of c-Myc, which colocalized with oxLDL/foam cells in the coronaries of WHHL rabbits. Conclusions —We provide the first evidence that oxLDL and α-tocopherol may influence c-Myc activation and several c-Myc–dependent signaling pathways in human coronary SMCs. The observation that in vivo, an antioxidant reduces both c-Myc and oxLDL in early coronary lesions of rabbits is consistent with, but does not prove, the hypothesis that c-Myc–dependent factors activated by oxidative processes contribute to atherogenesis and coronary heart disease.

Apoptosis of arterial cells induced by oxidized low density lipoproteins (OxLDL) is thought to contribute to the progression of atherosclerosis. However, most data on apoptotic effects and mechanisms of OxLDL were obtained with extensively oxidized LDL unlikely to occur in early stages of atherosclerotic lesions. We now demonstrate that mildly oxidized LDL generated by incubation with oxygen radical-producing xanthine/xanthine oxidase (X/XO) induces apoptosis in primary cultures of human coronary endothelial and SMC, as determined by TUNEL technique, DNA laddering, and FACS analysis. Apoptosis was markedly reduced when X/XO-LDL was generated in the presence of different oxygen radical scavengers. Apoptotic signals were mediated by intramembrane domains of both Fas and tumor necrosis factor (TNF) receptors I and II. Blocking of Fas ligand (FasL) reduced apoptosis by 50% and simultaneous blocking of FasL and TNF receptors by 70%. Activation of apoptotic receptors was accompanied by an increase of proapoptotic and a decrease in antiapoptotic proteins of the Bcl-2 family and resulted in marked activation of class I and II caspases. Mildly oxidized LDL also activated MAP and Jun kinases and increased p53 and other transcription factors (ATF-2, ELK-1, CREB, AP-1). Inhibitors of Map and Jun kinase significantly reduced apoptosis. Our results provide the first evidence that OxLDL-induced apoptosis involves TNF receptors and Jun activation. More important, they demonstrate that even mildly oxidized LDL formed in atherosclerotic lesions may activate a broad cascade of oxygen radical-sensitive signaling pathways affecting apoptosis and other processes influencing the evolution of plaques. Thus, we suggest that extensive oxidative modifications of LDL are not necessary to influence signal transduction and transcription in vivo.

The effects of angiotensin-converting enzyme (ACE)-inhibition with zofenopril on the development of atherosclerosis and low-density lipoprotein (LDL) oxidation were determined in Watanabe Heritable Hyperlipidemic (WHHL) rabbits. Rabbits received either placebo (n = 6) or 0.5 mg/kg/day of zofenopril (n = 6). After 6 weeks of treatment, the computer-assisted analysis revealed that zofenopril reduced the aortic and common carotid corrected cumulative lesion area by 34% and 39%, respectively (p < 0.05 vs placebo-treated group). The intimal/medial ratio of the largest fatty streaks was 0.426+/-0.158 in the zofenopril-treated group and 0.875+/-0.238 in the placebo-treated group (p < 0.05). Furthermore, we found in the zofenopril-treated group smaller lesions with an intimal/medial ratio of zofenopril also reduced plasmatic LDL oxidation, as shown by significant reduction of malondialdehyde content (p < 0.01) and relative agarose gel mobility (p < 0.05), as well as by the prolongation of the lag-time (p < 0.05). Compared to zofenopril-treated rabbits, arterial sections of the placebo-group had significant increase in the intimal presence of macrophages-derived foam cells (p < 0.05), ox-LDL (p < 0.01), and native LDL (p < 0.01) detected by immunocytochemistry with RAM-11, MDA2 and NP1533975 monoclonal antibodies, respectively. To investigate the amount of platelet accumulation in the atherosclerotic plaque we also measured platelet-associated radioactivity. Autologous platelets were labeled with 111Indiumoxine and injected intravenously. After 2 hours, WHHL were sacrificed and arterial sections were counted for platelet-associated radioactivity. In the placebo-treated group, platelet radioactivity was 0.52+/-0.12 equivalent of radioactivity per mg of tissue in the common carotid and 0.25+/-0.18 in the abdominal aorta; in contrast, rabbits treated by zofenopril had 0.20+/-0.12 in the common carotid and 0.06+/-0.01 in the abdominal aorta. These data indicate that ACE-inhibition with zofenopril has antiatherosclerotic and antioxidant effects in WHHL-rabbits. Our results also shows that these effects could be linked to a reduced wall-associated platelet deposition at the site of atherosclerotic lesions.

We have recently reported that neoplastic transformation of two rat thyroid epithelial cell lines by retroviruses carrying the v-mos and v-ras Ki oncogenes is associated with a drastic increase of AP-1 activity. The most important effects were represented by the dramatic junB and fra-1 gene induction, which was abolished by the block of the transformation-induced HMGI-C protein synthesis. Here, we have further characterized the transformation-dependent AP-1 activity, by analysing the expression of different jun- and fos-related components, in rat thyroid cell lines transformed by several oncogenes, in human thyroid carcinoma cell lines, and in naturally occurring human thyroid tumours. A significant increase of Fra-1 and JunB protein levels was detected in all oncogene transformed rat thyroid cell lines. Fra-1 gene induction was demonstrated to occur also in human thyroid carcinoma cell lines and tissues. Conversely, c-Jun and JunD proteins, rather than JunB, accumulated in human thyroid carcinoma cell lines. An induction of AP-1 target genes was also detected both in rat and human thyroid transformed cell lines. Therefore, in vivo and in vitro thyroid cell transformation is associated with important compositional changes in the AP-1 complex and an increased transcriptional activity.

We have investigated the role of the NFkappaB complex in the process of thyroid carcinogenesis by analysing thyroid carcinoma cell lines. A significant increase in p65 NFkappaB mRNA and protein expression, compared to normal thyroid cultures or tissue, was found in all of the cancer cell lines. Conversely, only a modest increase in the p50 NFkappaB mRNA and protein was found in most, but not all carcinoma cell lines. The block of p65 protein synthesis with specific antisense oligonucleotides greatly reduced the ability of two undifferentiated carcinoma cell lines to form colonies in agar and reduced their growth rate. On the other hand, no effect was observed in the same cell lines when treated with p50 specific antisense oligonucleotides. These inhibitory effects seem to be mediated by the suppression of c-myc gene expression, since treatment with antisense oligonucleotides for p65 gene interfered negatively with c-myc gene expression. Our results indicate that activation of the NFkappaB complex by overexpression of p65 plays a critical role in the process of thyroid cell transformation.

Background Essential hypertension is associated with enhanced LDL oxidation and impaired endothelium-dependent vasodilation. The antioxidant status is linked to the nitric oxide (NO) pathway. Sulfhydryl angiotensin-converting enzyme (ACE) inhibitors inhibit oxidative stress and atherogenesis in experimental models; therefore we tested whether this beneficial antioxidant activity could be also clinically relevant in patients with essential hypertension. Methods Plasma LDL oxidizability was investigated initially in untreated normocholesterolemic patients with moderate essential hypertension without clinically evident target organ damage (n 96) and in control normotensive subjects (n 46). Patients were then randomly assigned into two age- and sex-matched groups to receive the new sulfhydryl ACE inhibitor zofenopril (15 to 30 mg/d; n 48) or enalapril (20 mg/d, n 48). LDL oxidizability was evaluated (generation of malondialdehyde, MDA) and systemic oxidative stress was evaluated by isoprostanes (8-isoPGF2). Asymmetrical dimethyl-L-arginine (ADMA), a competitive inhibitor of endothelial NO synthase, and plasma nitrite and nitrates (NOx) were also measured. Results LDL from hypertensive subjects had enhanced susceptibility to oxidation in vitro compared with that in control subjects (P .05). Similarly, isoprostanes were significantly increased (P .01) in hypertensive subjects versus control subjects. After 12-week treatment, MDA levels were significantly reduced by zofenopril (P .05) but not enalapril treatment (P not significant). Isoprostanes were normalized after zofenopril treatment (P .03), whereas enalapril was ineffective. After treatment with both ACE inhibitors, plasma NOx concentrations were significantly reduced (P .05). Similarly, hypertension increased ADMA concentration compared with the normotensive state, whereas ACE inihibition elicited a significant decrease. However, the reduction of ADMA concentration was significantly higher in patients receiving sulfhydryl ACE inhibition (P .05 vs enalapril). Conclusions The sulfhydryl ACE inhibitor zofenopril reduces oxidative stress and improves the NO pathway in patients with essential hypertension. If confirmed in a large multicenter clinical trial, our data suggest a possible vasculoprotective effect of the compound in retarding vascular dysfunction and atherogenesis that often develops rapidly in hypertensive patients. (Am Heart J 2004;148:e5.) Low

Advanced stages of both cancer and atherosclerosis are characterized by a local increase in tissue mass that may be hard to control. This increase in tissue mass can be attributed to oxidation-sensitive modification of cell cycle-related events, including cellular proliferation, differentiation, and apoptosis, which could be secondary to alteration in the activity of tumor suppressor gene and oncogene products. The oncogene c-Myc has classically been considered to be involved in carcinogenesis and has more recently been implicated in both endothelial dysfunction and atherogenesis as well. Consequently, inhibition of c-Myc-dependent signaling has become a novel therapeutic opportunity and challenge in atherosclerosis and other cardiovascular diseases. Antioxidant strategies, RNA synthesis inhibitors such as mithramycin, and gene therapeutic approaches with antisense oligonucleotides against c-Myc are some of the promising strategies. In general, the increased biologic understanding of the participation of cell cycle events and targeting these events may enable to attenuate or prevent some of the complications of vascular and neoplastic diseases.

Background and Purpose —Calcium-channel blockers (CCBs) reduce systolic blood pressure and stroke-related mortality in stroke-prone spontaneously hypertensive rats (SPSHR). Brain ischemia is associated with loss of intracellular antioxidants. Increased formation of oxygen radicals and oxidation of LDL may enhance arterial vasoconstriction by various mechanisms. CCBs that also exert antioxidative properties in vitro may therefore be particularly useful. To investigate such antioxidant effects in vivo, we determined several parameters of LDL oxidation in SPSHR treated with two 1,4-dihydropyridine–type (1,4-DHP) CCBs of different lipophilic properties and compared them with antioxidant-treated and untreated controls. We also tested whether these drugs decrease the formation of oxidation-specific epitopes in arteries. Methods —Five groups of 9 to 14 SPSHR each (aged 8 weeks) were treated with 80 mg/kg body wt per day nifedipine, 1 mg or 0.3 mg/kg body wt per day lacidipine, vitamin E (100 IU/d), or carrier for 5 weeks. A group of Wistar-Kyoto rats was used as normotensive control. Plasma samples were taken, and LDL was isolated by ultracentrifugation. Then LDL was exposed to oxygen radicals generated by xanthine/xanthine oxidase reaction (2 mmol/L xanthine+100 mU/mL xanthine oxidase), and several parameters of oxidation were determined. The presence of native apolipoprotein B and oxidation-specific epitopes in the carotid and middle cerebral arteries was determined immunocytochemically. Results —1,4-DHP CCBs completely prevented mortality. Normotensive Wistar-Kyoto rats showed less oxidation than control SPSHR. Plasma lipoperoxide levels were 0.87±0.27 μmol/L in control SPSHR, 0.69±0.19 and 0.63±0.20 μmol/L in the groups treated with 0.3 and 1 mg lacidipine, respectively, and 0.68±0.23 μmol/L in nifedipine-treated animals ( P P P Conclusions —In the SPSHR model, 1,4-DHP CCBs reduce plasma and LDL oxidation and formation of oxidation-specific epitopes and prolong survival independently of blood pressure modifications. Our results support the concept that the in vivo protective effect of these drugs on cerebral ischemia and stroke may in part result from inhibition of oxidative processes.

RIZ1 isoform, but not RIZ2, is commonly silenced in many types of tumors. In osteosarcoma cells, RIZ1 protein is very abundant. The silencing of YY1 protein, a recent target gene in osteosarcoma cells, reduced the expression of RIZ1 protein. Here we show that RIZ1 overexpression is a transcriptional event documented by Western blot, RT-PCR, and promoter assays. YY1 protein binds and cooperates to positive regulation of the RIZ1 promoter and its presence reduced the dimethyl lysine 9 histone 3 by chromatin immunoprecipitation assays. These results indicate that overexpression of YY1 in osteosarcoma cells plays a key role in positive regulation of RIZ1. The coexpression of RIZ1/YY1 proteins suggests a tandem regulatory mechanism in human osteosarcoma cells and tissues.