2,906 research outputs found

    Synthesis and evaluation of biphenyl derivatives as potential downregulators of VEGF protein secretion and telomerase-related gene expressions

    Get PDF
    A group of 47 biphenyl functionalized compounds, prepared by means of Suzuki couplings, has been investigated for their cytotoxicity on two tumoral cell lines (HT-29 and MCF-7) and one non tumoral cell line (HEK-293). 29 selected compounds have been investigated for their ability to inhibit the production of the vascular endothelial growth factor (VEGF). Subsequently, the capacity of the compounds to downregulate the expression of the VEGF, h-TERT and c-Myc genes, the two latter involved in the control of the activation of telomerase, has also been determined.Financial support has been granted to M.C. by the Ministerio de Economía y Competitividad of Spain (project CTQ2014- 52949-P), by the Consellería d´Empresa, Universitat i Ciencia de la Generalitat Valenciana (projects PROMETEO/2013/027 and ACOMP/2014/ 274) and by the University Jaume I (project PI- 1B2011-37). M. S.-P. thanks the University Jaume I for a predoctoral fellowship

    Sex and Exposure to Postnatal Chlorpyrifos Influence the Epigenetics of Feeding-Related Genes in a Transgenic APOE Mouse Model:Long-Term Implications on Body Weight after a High-Fat Diet

    Get PDF
    Developmental exposure to toxicants and diet can interact with an individual's genetics and produce long-lasting metabolic adaptations. The different isoforms of the apolipoprotein E (APOE) are an important source of variability in metabolic disorders and influence the response to the pesticide chlorpyrifos (CPF). We aimed to study the epigenetic regulation on feeding control genes and the influence of postnatal CPF exposure, APOE genotype, and sex, and how these modifications impact on the metabolic response to a high-fat diet (HFD). Both male and female apoE3- and apoE4-TR mice were exposed to CPF on postnatal days 10-15. The DNA methylation pattern of proopiomelanocortin, neuropeptide Y, leptin receptor, and insulin-like growth factor 2 was studied in the hypothalamus. At adulthood, the mice were given a HFD for eight weeks. The results highlight the importance of sex in the epigenetic regulation and the implication of CPF treatment and APOE genotype. The body weight progression exhibited sex-dimorphic differences, apoE4-TR males being the most susceptible to the effects induced by CPF and HFD. Overall, these results underscore the pivotal role of sex, APOE genotype, and developmental exposure to CPF on subsequent metabolic disturbances later in life and show that sex is a key variable in epigenetic regulation

    Synthesis and biological evaluation of truncated α-tubulin-binding pironetin analogues lacking alkyl pendants in the side chain or the dihydropyrone ring

    Get PDF
    The preparation of several new truncated analogues of the natural dihydropyrone pironetin is described. They differ from the natural product mainly in the suppression of some of the alkyl pendants in either the side chain or the dihydropyrone ring. Their cytotoxic activity and their interactions with tubulin have been investigated. It has been found that all analogues are cytotoxic towards two either sensitive or resistant tumoral cell lines with similar IC50 values in each case, thus strongly suggesting that, like natural pironetin, they also display a covalent mechanism of action. Their cytotoxicity is, however, lower than that of the parent compound. This indicates that all alkyl pendants are necessary for the full biological activity, with the ethyl group at C-4 seemingly being particularly relevant. Most likely, the alkyl groups cause a restriction in the conformational mobility of the molecule and reduce the number of available conformations. This makes it more probable that the molecule preferentially adopts a shape which fits better into the binding point in α-tubulin

    Cancer stem cells from human glioblastoma resemble but do not mimic original tumors after in vitro passaging in serum-free media

    Get PDF
    Human gliomas harbour cancer stem cells (CSCs) that evolve along the course of the disease, forming highly heterogeneous subpopulations within the tumour mass. These cells possess self-renewal properties and appear to contribute to tumour initiation, metastasis and resistance to therapy. CSC cultures isolated from surgical samples are considered the best preclinical in vitro model for primary human gliomas. However, it is not yet well characterized to which extent their biological and functional properties change during in vitro passaging in the serum-free culture conditions. Here, we demonstrate that our CSC-enriched cultures harboured from one to several CSC clones from the human glioma sample. When xenotransplanted into mouse brain, these cells generated tumours that reproduced at least three different dissemination patterns found in original tumours. Along the passages in culture, CSCs displayed increased expression of stem cell markers, different ratios of chromosomal instability events, and a varied response to drug treatment. Our findings highlight the need for better characterization of CSC-enriched cultures in the context of their evolution in vitro, in order to uncover their full potential as preclinical models in the studies aimed at identifying molecular biomarkers and developing new therapeutic approaches of human gliomas.Peer reviewe

    Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

    Get PDF
    The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
    corecore