156 research outputs found
Short and highly efficient synthetic promoters for melanoma-specific gene expression.
Here, we report the construction and functional analysis of synthetic promoters designed for gene therapy applications requiring strong and specific gene expression in melanoma cell lines. We have analysed the transcriptional activity of different combinations of two transcriptional regulatory modules, a melanocyte-specific element from the human tyrosinase promoter and a cell-cycle-specific element from the human alpha-fetoprotein promoter. Transient expression assays in different cell lines show that several of these composite synthetic promoters can drive a strong and selective expression of a reporter gene in melanoma cell, providing us with a new powerful tool for gene therapy of melanomas
Involvement of aryl hydrocarbon receptor signaling in the development of small cell lung cancer induced by HPV E6/E7 oncoproteins
<p>Abstract</p> <p>Background</p> <p>Lung cancers consist of four major types that and for clinical-pathological reasons are often divided into two broad categories: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). All major histological types of lung cancer are associated with smoking, although the association is stronger for SCLC and squamous cell carcinoma than adenocarcinoma. To date, epidemiological studies have identified several environmental, genetic, hormonal and viral factors associated with lung cancer risk. It has been estimated that 15-25% of human cancers may have a viral etiology. The human papillomavirus (HPV) is a proven cause of most human cervical cancers, and might have a role in other malignancies including vulva, skin, oesophagus, head and neck cancer. HPV has also been speculated to have a role in the pathogenesis of lung cancer. To validate the hypothesis of HPV involvement in small cell lung cancer pathogenesis we performed a gene expression profile of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins.</p> <p>Methods</p> <p>Gene expression profile of SCLC has been performed using Agilent whole mouse genome (4 × 44k) representing ~ 41000 genes and mouse transcripts. Samples were obtained from two HPV16-E6/E7 transgenic mouse models and from littermate's normal lung. Data analyses were performed using GeneSpring 10 and the functional classification of deregulated genes was performed using Ingenuity Pathway Analysis (Ingenuity<sup>® </sup>Systems, <url>http://www.ingenuity.com</url>).</p> <p>Results</p> <p>Analysis of deregulated genes induced by the expression of E6/E7 oncoproteins supports the hypothesis of a linkage between HPV infection and SCLC development. As a matter of fact, comparison of deregulated genes in our system and those in human SCLC showed that many of them are located in the Aryl Hydrocarbon Receptor Signal transduction pathway.</p> <p>Conclusions</p> <p>In this study, the global gene expression of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins led us to identification of several genes involved in SCLC tumor development. Furthermore, our study reveled that the Aryl Hydrocarbon Receptor Signaling is the primarily affected pathway by the E6/E7 oncoproteins expression and that this pathway is also deregulated in human SCLC. Our results provide the basis for the development of new therapeutic approaches against human SCLC.</p
Psychological Stress and Cancer: New Evidence of An Increasingly Strong Link
To date stress, a highly complex process that disrupts homeostasis and involves environmental and psychosocial factors, is considered as one of the most crucial factor that affects our daily life, especially urban dweller's life. Clinical and experimental studies widely support the notion that adrenergic stimulation due to chronic stress affects inflammation and metabolism. In this work, supported by several recent scientific evidences, we show how stress plays a positive role in cancer initiation, progression and cancer metastasis, a negative role for anti-tumor immune function and therapy response. Understanding the intricacies of this interaction could provide an additional help on how act in cancer prevention and therap
Detection and genotyping of human Papillomavirus in urine samples from unvaccinated male and female adolescents in Italy
The introduction of vaccination against Human Papillomavirus (HPV) in adolescent girls in 2006 has focused virological surveillance on this age group. As few studies have evaluated HPV infections in young populations, further data are needed in order to improve and extend prophylactic policy and to monitor epidemiological changes. The present study aimed at evaluating overall and type-specific HPV prevalence in both female and male adolescents in Italy. HPV DNA detection and genotyping was performed on urine samples collected from 870 unvaccinated adolescents (369 females, 501 males, 11-18 years of age) in five cities in Italy. Following DNA extraction by means of a commercial kit (NucliSENS®-miniMAG®, bioMérieux), the L1 gene fragment was PCR amplified and genotyped by restriction fragment length polymorphism analysis. HPV DNA was detected in 1.5% of all samples, and in 3% and 0.4% of samples from females and males, respectively. In approximately 70% of HPV DNA positive adolescents, the infection was due to a single genotype, with 88.9% of genotypes belonging to the HR-clade. The only two HPV-positive boys (14 and 18 years old) had HPV-70 genotype. Only one of the 11 HPV-infected girls was in the 11-14 age-group. HPV prevalence was 4.2% in girls aged 15-18 years and 60% of infections were due to vaccine types HPV-16 or HPV-6/-11. This is one of the few studies, the first conducted in Italy, on HPV infection in adolescents. Urine testing is the easier way of detecting HPV infection in younger populations. Our data revealed a very low HPV prevalence, and no infections were observed in the 12-year-old vaccine target population. The majority of infections were seen in females aged 15-18 years. Overall, more than 50% and 30% of the potentially persistent HPV infections detected in this group could have been prevented by the quadrivalent and the bivalent vaccines, respectively
Apolipoprotein(a) kringle-IV type 2 copy number variation is associated with venous thromboembolism
In addition to the established association between high lipoprotein(a) [Lp(a)] concentrations and coronary artery disease, an association between Lp(a) and venous thromboembolism (VTE) has also been described. Lp(a) is controlled by genetic variants in LPA gene, coding for apolipoprotein(a), including the kringle-IV type 2 (KIV-2) size polymorphism. Aim of the study was to investigate the role of LPA gene KIV-2 size polymorphism and single nucleotide polymorphisms (SNPs) (rs1853021, rs1800769, rs3798220, rs10455872) in modulating VTE susceptibility. Five hundred and sixteen patients with VTE without hereditary and acquired thrombophilia and 1117 healthy control subjects, comparable for age and sex, were investigated. LPA KIV-2 polymorphism, rs3798220 and rs10455872 SNPs were genotyped by TaqMan technology. Concerning rs1853021 and rs1800769 SNPs, PCR-RFLP assay was used. LPA KIV-2 repeat number was significantly lower in patients than in controls [median (interquartile range) 11(6-17) vs 15(9-25), p<0.0001]. A significantly higher prevalence of KIV-2 repeat number ≤7 was observed in patients than in controls (33.5% vs 15.5%, p<0.0001). KIV-2 repeat number was independently associated with VTE (p = 4.36 x10-9), as evidenced by the general linear model analysis adjusted for transient risk factors. No significant difference in allele frequency for all SNPs investigated was observed. Haplotype analysis showed that LPA haplotypes rather than individual SNPs influenced disease susceptibility. Receiver operating characteristic curves analysis showed that a combined risk prediction model, including KIV-2 size polymorphism and clinical variables, had a higher performance in identifying subjects at VTE risk than a clinical-only model, also separately in men and women
miR-519d Overexpression Is Associated With Human Obesity
Obesity is a consequence of imbalance of food intake and energy expenditure that results in storage of energy as fat, primarily in adipose tissue. MicroRNAs are non-coding RNAs that regulate gene expression in metabolic pathways and they are also involved in fat-cell development. The aim of this study was to evaluate whether microRNA dysfunction contributes to obesity. We analyzed, by microarray, the expression profile of 1,458 microRNAs in subcutaneous adipose tissue (SAT) from nondiabetic severely obese (n = 20) and nonobese adults (n = 8). Among 42 differently expressed microRNAs, we confirmed by reverse-transcription PCR (RT-PCR) that miR-519d was overexpressed whereas the protein levels of peroxisome proliferator-activated receptor-α (PPARA) (a predicted miR 519d target) were lower, at western analysis, in severely obese vs. nonobese subjects. We also show that miR-519d specifically and dose-dependently suppressed translation of the PPARA protein, and increased lipid accumulation during preadipocyte differentiation. Because PPARA plays a central role in fatty acid homeostasis, and in the transcriptional regulation of genes that are necessary for maintenance of the redox balance during the oxidative catabolism of fatty acids, we suggest that PPARA loss and miR-519d overexpression could be associated with metabolic imbalance and subsequent adipocyte hypertrophy in SAT during obesity
Screening for thrombophilia and antithrombotic prophylaxis in pregnancy: Guidelines of the italian society for Haemostasis and Thrombosis (SISET)
Different outcome of six homozygotes for prothrombin A20210A gene variant
Prothrombin G20210A gene variant (FII G20210A) is a risk factor for venous thrombotic disease while conflicting results have been reported for the risk of arterial thrombotic events. However, vascular episodes were absent in up to 40% of the 67 homozygotes for the G20210A described so far, which indicates that the clinical expression depends on additional risk/trigger factors. We describe six homozygotes for the G20210A variant, among which the first pair of siblings (cases n. 3 and 4) reported so far that displayed a strongly heterogeneous clinical outcome. Case 1, a female of 27 years, developed a full thrombosis of common femoral, superficial and popliteal veins. She assumed oral contraceptives in the last two years. Case n. 2, 34 years old, suffered of recurrent pregnancy loss in absence of any causative alteration. Cases n. 3 and n. 5 experienced arterial thrombotic disease, i.e., juvenile myocardial infarction (40 years old) and stroke (48 years old), respectively, in absence of other risk factors. Finally, cases n. 4 and 6 identified as homozygotes for the FII G20210A variant being consanguineous of symptomatic subjects bearing the variant, did not experience any episode of venous nor arterial disease. Both of them have chronic liver disease with an impairement of the prothrombin time INR. Thus, homozygotes for the G20210A are at risk for arterial (in addition to venous) thromobotic events; chronic liver disease might modulate this risk
Identification of a novel zinc metalloprotease through a global analysis of clostridium difficile extracellular proteins
Clostridium difficile is a major cause of infectious diarrhea worldwide. Although the cell surface proteins are recognized to be important in clostridial pathogenesis, biological functions of only a few are known. Also, apart from the toxins, proteins exported by C. difficile into the extracellular milieu have been poorly studied. In order to identify novel extracellular factors of C. difficile, we analyzed bacterial culture supernatants prepared from clinical isolates, 630 and R20291, using liquid chromatography-tandem mass spectrometry. The majority of the proteins identified were non-canonical extracellular proteins. These could be largely classified into proteins associated to the cell wall (including CWPs and extracellular hydrolases), transporters and flagellar proteins. Seven unknown hypothetical proteins were also identified. One of these proteins, CD630_28300, shared sequence similarity with the anthrax lethal factor, a known zinc metallopeptidase. We demonstrated that CD630_28300 (named Zmp1) binds zinc and is able to cleave fibronectin and fibrinogen in vitro in a zinc-dependent manner. Using site-directed mutagenesis, we identified residues important in zinc binding and enzymatic activity. Furthermore, we demonstrated that Zmp1 destabilizes the fibronectin network produced by human fibroblasts. Thus, by analyzing the exoproteome of C. difficile, we identified a novel extracellular metalloprotease that may be important in key steps of clostridial pathogenesis
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