57 research outputs found

    Molecular characterization of membrane steroid receptors in hormone-sensitive cancers

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    Cancer is one of the most common causes of death worldwide, and its development is a re-sult of the complex interaction of genetic factors, environmental cues, and aging. Hormone-sensitive cancers depend on the action of one or more hormones for their development and progression. Sex steroids and corticosteroids can regulate different physiological functions, including metabolism, growth, and proliferation, through their interaction with specific nuclear receptors, that can tran-scriptionally regulate target genes via their genomic actions. Therefore, interference with hormones’ activities, e.g., deregulation of their production and downstream pathways or the exposition to exogenous hormone-active substances such as endocrine-disrupting chemicals (EDCs), can affect the regulation of their correlated pathways and trigger the neoplastic transformation. Although nuclear receptors account for most hormone-related biologic effects and their slow genomic responses are well-studied, less-known membrane receptors are emerging for their ability to mediate steroid hormones effects through the activation of rapid non-genomic responses also involved in the development of hormone-sensitive cancers. This review aims to collect pre-clinical and clinical data on these extranuclear receptors not only to draw attention to their emerging role in cancer development and progression but also to highlight their dual role as tumor microenvironment players and potential candidate drug targets

    Conformational altered p53 affects neuronal function: relevance for the response to toxic insult and growth-associated protein 43 expression

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    The role of p53 in neurodegenerative diseases is essentially associated with neuronal death. Recently an alternative point of view is emerging, as altered p53 conformation and impaired protein function have been found in fibroblasts and blood cells derived from Alzheimer's disease patients. Here, using stable transfected SH-SY5Y cells overexpressing APP751wt (SY5Y-APP) we demonstrated that the expression of an unfolded p53 conformation compromised neuronal functionality. In particular, these cells showed (i) augmented expression of amyloid precursor protein (APP) and its metabolites, including the C-terminal fragments C99 and C83 and β-amyloid peptide (ii) high levels of oxidative markers, such as 4-hydroxy-2-nonenal Michael-adducts and 3-nitro-tyrosine and (iii) altered p53 conformation, mainly due to nitration of its tyrosine residues. The consequences of high-unfolded p53 expression resulted in loss of p53 pro-apoptotic activity, and reduction of growth-associated protein 43 (GAP-43) mRNA and protein levels. The role of unfolded p53 in cell death resistance and lack of GAP-43 transcription was demonstrated by ZnCl(2) treatment. Zinc supplementation reverted p53 wild-type tertiary structure, increased cells sensitivity to acute cytotoxic injury and GAP-43 levels in SY5Y-APP clone

    Increased susceptibility to Chrysanthemum Yellows phytoplasma infection in Atcals7ko plants is accompanied by enhanced expression of carbohydrate transporters

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    Main conclusion: Loss of CALS7 appears to confer increased susceptibility to phytoplasma infection in Arabidopsis, altering expression of genes involved in sugar metabolism and membrane transport. Abstract: Callose deposition around sieve pores, under control of callose synthase 7 (CALS7), has been interpreted as a mechanical response to limit pathogen spread in phytoplasma-infected plants. Wild-type and Atcals7ko mutants were, therefore, employed to unveil the mode of involvement of CALS7 in the plant’s response to phytoplasma infection. The fresh weights of healthy and CY-(Chrysanthemum Yellows) phytoplasma-infected Arabidopsis wild type and mutant plants indicated two superimposed effects of the absence of CALS7: a partial impairment of photo-assimilate transport and a stimulated phytoplasma proliferation as illustrated by a significantly increased phytoplasma titre in Atcal7ko mutants. Further studies solely dealt with the effects of CALS7 absence on phytoplasma growth. Phytoplasma infection affected sieve-element substructure to a larger extent in mutants than in wild-type plants, which was also true for the levels of some free carbohydrates. Moreover, infection induced a similar upregulation of gene expression of enzymes involved in sucrose cleavage (AtSUS5, AtSUS6) and transmembrane transport (AtSWEET11) in mutants and wild-type plants, but an increased gene expression of carbohydrate transmembrane transporters (AtSWEET12, AtSTP13, AtSUC3) in infected mutants only. It remains still unclear how the absence of AtCALS7 leads to gene upregulation and how an increased intercellular mobility of carbohydrates and possibly effectors contributes to a higher susceptibility. It is also unclear if modified sieve-pore structures in mutants allow a better spread of phytoplasmas giving rise to higher titre

    Filamentous sieve element proteins are able to limit phloem mass flow, but not phytoplasma spread

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    In Fabaceae, dispersion of forisomes\u2014highly ordered aggregates of sieve element proteins\u2014in response to phytoplasma infection was proposed to limit phloem mass flow and, hence, prevent pathogen spread. In this study, the involvement of filamentous sieve element proteins in the containment of phytoplasmas was investigated in non-Fabaceae plants. Healthy and infected Arabidopsis plants lacking one or two genes related to sieve element filament formation\u2014AtSEOR1 (At3g01680), AtSEOR2 (At3g01670), and AtPP2-A1 (At4g19840)\u2014were analysed. TEM images revealed that phytoplasma infection induces phloem protein filament formation in both the wild-type and mutant lines. This result suggests that, in contrast to previous hypotheses, sieve element filaments can be produced independently of AtSEOR1 and AtSEOR2 genes. Filament presence was accompanied by a compensatory overexpression of sieve element protein genes in infected mutant lines in comparison with wild-type lines. No correlation was found between phloem mass flow limitation and phytoplasma titre, which suggests that sieve element proteins are involved in defence mechanisms other than mechanical limitation of the pathogen

    Evaluation of a large set of patients with Autoimmune Polyglandular Syndrome from a single reference centre in context of different classifications

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    Purpose: To characterize patients with APS and to propose a new approach for their follow-up. Query ID="Q1" Text="Please check the given names and familynames." Methods: Monocentric observational retrospective study enrolling patients referred to the Outpatients clinic of the Units of Endocrinology, Diabetology, Gastroenterology, Rheumatology and Clinical Immunology of our Hospital for Autoimmune diseases. Results: Among 9852 patients, 1174 (11.9%) [869 (73.9%) female] were diagnosed with APS. In 254 subjects, the diagnosis was made at first clinical evaluation (Group 1), all the other patients were diagnosed with a mean latency of 11.3 ± 10.6 years (Group 2). Group 1 and 2 were comparable for age at diagnosis (35.7 ± 16.3 vs. 40.4 ± 16.6 yrs, p =.698), but different in male/female ratio (81/173 vs 226/696, p =.019). In Group 2, 50% of patients developed the syndrome within 8 years of follow-up. A significant difference was found after subdividing the first clinical manifestation into the different outpatient clinic to which they referred (8.7 ± 8.0 vs. 13.4 ± 11.6 vs. 19.8 ± 8.7 vs. 7.4 ± 8.1 for endocrine, diabetic, rheumatologic, and gastroenterological diseases, respectively, p <.001). Conclusions: We described a large series of patients affected by APS according to splitters and lumpers. We propose a flowchart tailored for each specialist outpatient clinic taking care of the patients. Finally, we recommend regular reproductive system assessment due to the non-negligible risk of developing premature ovarian failure

    Conformational Altered p53 as an Early Marker of Oxidative Stress in Alzheimer's Disease

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    In order to study oxidative stress in peripheral cells of Alzheimer's disease (AD) patients, immortalized lymphocytes derived from two peculiar cohorts of patients, referring to early onset AD (EOSAD) and subjects harboured AD related mutation (ADmut), were used. Oxidative stress was evaluated measuring i) the typical oxidative markers, such as HNE Michel adducts, 3 Nitro-Tyrosine residues and protein carbonyl on protein extracts, ii) and the antioxidant capacity, following the enzymatic kinetic of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GRD). We found that the signs of oxidative stress, measured as oxidative marker levels, were evident only in ADmut but not in EOSAD patients. However, oxidative imbalance in EOSAD as well as ADmut lymphocytes was underlined by a reduced SOD activity and GRD activity in both pathological groups in comparison with cells derived from healthy subjects. Furthermore, a redox modulated p53 protein was found conformational altered in both EOSAD and ADmut B lymphocytes in comparison with control cells. This conformational altered p53 isoform, named “unfolded p53”, was recognized by the use of two specific conformational anti-p53 antibodies. Immunoprecipitation experiments, performed with the monoclonal antibodies PAb1620 (that recognizes p53wt) and PAb240 (that is direct towards unfolded p53), and followed by the immunoblotting with anti-4-hydroxynonenal (HNE) and anti- 3-nitrotyrosine (3NT) antibodies, showed a preferential increase of nitrated tyrosine residues in unfolded p53 isoform comparing to p53 wt protein, in both ADmut and EOSAD. In addition, a correlation between unfolded p53 and SOD activity was further found. Thus this study suggests that ROS/RNS contributed to change of p53 tertiary structure and that unfolded p53 can be considered as an early marker of oxidative imbalance in these patients
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