149 research outputs found
First records of the summerfruit tοrticid, Adoxophyes oranα F. ν .R. in Greece
Το πολυφάγο Αεπιδόπτερο Adoxophyes orana F.v.R. της οικογένειας Tortricidae παρατηρήθηκε για πρώτη φορά στην περιοχή της Νάουσας το 1985, σε μηλιές, ροδακινιές και κερασιές, όπου προσέβαλε την άνοιξη τους οφθαλμούς και αργότερα τα φύλλα και τους καρπούς. Πιθανότατα εισήλθε στην Ελλάδα από τη γειτονική Γιουγκοσλαβία, όπου ήταν γνωστό και προκαλούσε ζημιά στα οπωροφόρα δέντρα τουλάχιστον από το 1975. Το ενήλικο σε γενικό χρωματισμό και μορφή μοιάζει με το επίσης πολυφάγο φυλλοδετικό Λεπιδόπτερο.4Γί7φί rosanus L. Το άνοιγμα των πτερύγων στο ενήλικο αρσενικό είναι 15-20 mm και το θηλυκό 19-22 mm. Οι πρόσθιες πτέρυγες στο αρσενικό έχουν βασικό χρώμα κίτρινο ώχρας και στο θηλυκό σκοτεινότερο, συχνά καστανόμαυρο. Οι πτέρυγες αυτές και στα δύο φύλλα, έχουν χαρακτηριστικές κηλίδες και λωρίδες σκοτεινότερες από το βασικό χρώμα. Η πλήρως αναπτυγμένη προνύμφη είναι πράσινη και μήκους 18-20 mm.In spring 1985, buds of apple and peach trees in the Naoussa area of northern Greece were severely damaged by larvae of a tortricid moth. Adults emerged in late May and early June. Later in the season, we found larvae of the same species established and feeding on leaves and green or ripe fruits of apple and peach, as well as on ripe cherries. Larvae collected in late June were reared in the laboratory on peach leaves and on an artificial diet. The adults obtained were identified as Adoxophyes orana Fischer von Rosslerstamm (Lepidoptera. Tortricidae). A. orana is a synonym of A. reticulates Huebner, A.tripsiana Eversmann, A. fasciata Walsh., or Capua or Cacoecia reticulana Huebner and most probably, is a recent introduction to Greece. The damage it causes to fruits such as apples, peaches and cherries is such that it could not have escaped the attention of fruit growers and plant protection specialists if the insect had earlier been present in the country. A. orana has been established and caused damage to fruit trees in northwest and central Europe for approximately fifty years and in southern Yugoslavia for at least the last ten years. It is probable that it spread to northern Greece from neighboring Yugoslavia. In the Naoussa area, the moths laid their eggs in batches on fruits or leaves. On peach and cherry the eggs were laid on both sides of the leaves, whereas on apple on the upper side as was observed also in other countries. In early October, the larvae abandoned their feeding sites and went next to auxiliary buds and crevices of the bark of branches to spin their hibernating webs. The adult maleof A. orana has a wingspan of 15-20 mm and the female one of 19-22 mm. The fore wings of the male are yellow ochre reddish, and have distinct rusty-red designs. There is a basal darker (brown) area, and two large darker stripes. The median one departs from the basal third of the costa and terminates, widening or divided in two branches, at the tornus. The other stripe is preapical and may take the form of a triangular spot of which sometimes only the borders are visible. The fore wings of the female are normally darker than those of the male, often blackish-brown, and have darker and dimmer stripes and other markings. The hind wings are light grey in the male and grey-brown in the female. The ground colour in the specimens of northwestern Europe is varying from light brown to dark brown. The fully grown larva is 18-20 mm long, green, with a light brown head. It somewhat resembles the larva of another tortricid, Archipsrosanus L. which is a monovoltine polyphagous species common in Greek orchards in spring. A. orana is polyvoltine and feeds on buds, leaves and fruits of a great number of cultivated and wild plants. Among its reported many hosts are species of Betula, Crataegus, Cydonia, Gossypium, Ligustrum, Lonicera, Malus, Medicago, Pyrus, Populus, Pistacia, Parrotia, Proms,Quercus, Ribes, Rubus, Rosa, Salix, Solanum, Syringa, Tilia, Ulmus, Vaccinium and the grapevine Vitis vinifera
Biglycan Regulates MG63 Osteosarcoma Cell Growth Through a LPR6/β-Catenin/IGFR-IR Signaling Axis
Biglycan, a small leucine rich proteoglycan (SLRP), is an important participant in bone homeostasis and development as well as in bone pathology. In the present study biglycan was identified as a positive regulator of MG63 osteosarcoma cell growth (p ≤ 0.001). IGF-I was shown to increase biglycan expression (p ≤ 0.01), whereas biglycan-deficiency attenuated significantly both basal and IGF-I induced cell proliferation of MG63 cells (p ≤ 0.001; p ≤ 0.01, respectively). These effects were executed through the IGF-IR receptor whose activation was strongly attenuated (p ≤ 0.01) in biglycan-deficient MG63 cells. Biglycan, previously shown to regulate Wnt/β-catenin pathway, was demonstrated to induce a significant increase in β-catenin protein expression evident at cytoplasmic (p ≤ 0.01), membrane (p ≤ 0.01), and nucleus fractions in MG63 cells (p ≤ 0.05). As demonstrated by immunofluorescence, increase in β-catenin expression is attributed to co-localization of biglycan with the Wnt co-receptor low-density lipoprotein receptor-related protein 6 (LRP6) resulting in attenuated β-catenin degradation. Furthermore, applying anti-β-catenin and anti-pIGF-IR antibodies to MG-63 cells demonstrated a cytoplasmic and to the membrane interaction between these molecules that increased upon exogenous biglycan treatment. In parallel, the downregulation of biglycan significantly inhibited both basal and IGF-I-dependent ERK1/2 activation, (p ≤ 0.001). In summary, we report a novel mechanism where biglycan through a LRP6/β-catenin/IGF-IR signaling axis enhances osteosarcoma cell growth
Inflammation and Metabolism in Cancer Cell—Mitochondria Key Player
Cancer metabolism is an essential aspect of tumorigenesis, as cancer cells have increased energy requirements in comparison to normal cells. Thus, an enhanced metabolism is needed in order to accommodate tumor cells' accelerated biological functions, including increased proliferation, vigorous migration during metastasis, and adaptation to different tissues from the primary invasion site. In this context, the assessment of tumor cell metabolic pathways generates crucial data pertaining to the mechanisms through which tumor cells survive and grow in a milieu of host defense mechanisms. Indeed, various studies have demonstrated that the metabolic signature of tumors is heterogeneous. Furthermore, these metabolic changes induce the exacerbated production of several molecules, which result in alterations that aid an inflammatory milieu. The therapeutic armentarium for oncology should thus include metabolic and inflammation regulators. Our expanding knowledge of the metabolic behavior of tumor cells, whether from solid tumors or hematologic malignancies, may provide the basis for the development of tailor-made cancer therapies
Syndecan-1 and FGF-2, but Not FGF Receptor-1, Share a Common Transport Route and Co-Localize with Heparanase in the Nuclei of Mesenchymal Tumor Cells
Syndecan-1 forms complexes with growth factors and their cognate receptors in the cell membrane. We have previously reported a tubulin-mediated translocation of syndecan-1 to the nucleus. The transport route and functional significance of nuclear syndecan-1 is still incompletely understood. Here we investigate the sub-cellular distribution of syndecan-1, FGF-2, FGFR-1 and heparanase in malignant mesenchymal tumor cells, and explore the possibility of their coordinated translocation to the nucleus. To elucidate a structural requirement for this nuclear transport, we have transfected cells with a syndecan-1/EGFP construct or with a short truncated version containing only the tubulin binding RMKKK sequence. The sub-cellular distribution of the EGFP fusion proteins was monitored by fluorescence microscopy. Our data indicate that syndecan-1, FGF-2 and heparanase co-localize in the nucleus, whereas FGFR-1 is enriched mainly in the perinuclear area. Overexpression of syndecan-1 results in increased nuclear accumulation of FGF-2, demonstrating the functional importance of syndecan-1 for this nuclear transport. Interestingly, exogenously added FGF-2 does not follow the route taken by endogenous FGF-2. Furthermore, we prove that the RMKKK sequence of syndecan-1 is necessary and sufficient for nuclear translocation, acting as a nuclear localization signal, and the Arginine residue is vital for this localization. We conclude that syndecan-1 and FGF-2, but not FGFR-1 share a common transport route and co-localize with heparanase in the nucleus, and this transport is mediated by the RMKKK motif in syndecan-1. Our study opens a new perspective in the proteoglycan field and provides more evidence of nuclear interactions of syndecan-1
1-methylnicotinamide and its structural analog 1,4-dimethylpyridine for the prevention of cancer metastasis
Background: 1-methylnicotinamide (1-MNA), an endogenous metabolite of nicotinamide, has recently gained interest due to its anti-inflammatory and anti-thrombotic activities linked to the COX-2/PGI2 pathway. Given the previously reported anti-metastatic activity of prostacyclin (PGI2), we aimed to assess the effects of 1-MNA and its structurally related analog, 1,4-dimethylpyridine (1,4-DMP), in the prevention of cancer metastasis. Methods: All the studies on the anti-tumor and anti-metastatic activity of 1-MNA and 1,4-DMP were conducted using the model of murine mammary gland cancer (4T1) transplanted either orthotopically or intravenously into female BALB/c mouse. Additionally, the effect of the investigated molecules on cancer cell-induced angiogenesis was estimated using the matrigel plug assay utilizing 4T1 cells as a source of pro-angiogenic factors. Results: Neither 1-MNA nor 1,4-DMP, when given in a monotherapy of metastatic cancer, influenced the growth of 4T1 primary tumors transplanted orthotopically; however, both compounds tended to inhibit 4T1 metastases formation in lungs of mice that were orthotopically or intravenously inoculated with 4T1 or 4T1-luc2-tdTomato cells, respectively. Additionally, while 1-MNA enhanced tumor vasculature formation and markedly increased PGI2 generation, 1,4-DMP did not have such an effect. The anti-metastatic activity of 1-MNA and 1,4-DMP was further confirmed when both agents were applied with a cytostatic drug in a combined treatment of 4T1 murine mammary gland cancer what resulted in up to 80 % diminution of lung metastases formation. Conclusions: The results of the studies presented below indicate that 1-MNA and its structural analog 1,4-DMP prevent metastasis and might be beneficially implemented into the treatment of metastatic breast cancer to ensure a comprehensive strategy of metastasis control
Interchromosomal Duplications on the Bactrocera oleae Y Chromosome Imply a Distinct Evolutionary Origin of the Sex Chromosomes Compared to Drosophila
BACKGROUND: Diptera have an extraordinary variety of sex determination mechanisms, and Drosophila melanogaster is the paradigm for this group. However, the Drosophila sex determination pathway is only partially conserved and the family Tephritidae affords an interesting example. The tephritid Y chromosome is postulated to be necessary to determine male development. Characterization of Y sequences, apart from elucidating the nature of the male determining factor, is also important to understand the evolutionary history of sex chromosomes within the Tephritidae. We studied the Y sequences from the olive fly, Bactrocera oleae. Its Y chromosome is minute and highly heterochromatic, and displays high heteromorphism with the X chromosome. METHODOLOGY/PRINCIPAL FINDINGS: A combined Representational Difference Analysis (RDA) and fluorescence in-situ hybridization (FISH) approach was used to investigate the Y chromosome to derive information on its sequence content. The Y chromosome is strewn with repetitive DNA sequences, the majority of which are also interdispersed in the pericentromeric regions of the autosomes. The Y chromosome appears to have accumulated small and large repetitive interchromosomal duplications. The large interchromosomal duplications harbour an importin-4-like gene fragment. Apart from these importin-4-like sequences, the other Y repetitive sequences are not shared with the X chromosome, suggesting molecular differentiation of these two chromosomes. Moreover, as the identified Y sequences were not detected on the Y chromosomes of closely related tephritids, we can infer divergence in the repetitive nature of their sequence contents. CONCLUSIONS/SIGNIFICANCE: The identification of Y-linked sequences may tell us much about the repetitive nature, the origin and the evolution of Y chromosomes. We hypothesize how these repetitive sequences accumulated and were maintained on the Y chromosome during its evolutionary history. Our data reinforce the idea that the sex chromosomes of the Tephritidae may have distinct evolutionary origins with respect to those of the Drosophilidae and other Dipteran families
Specific Syndecan-1 Domains Regulate Mesenchymal Tumor Cell Adhesion, Motility and Migration
Malignant mesothelioma is an asbestos induced cancer that is difficult to diagnose.
Several studies have combined biomarkers to improve mesothelioma diagnosis, but
with moderate success, and there is a need for new mesothelioma biomarkers. The
tumour is often resistant to treatment and most patients will survive less than a year.
An indicator of patient survival is the tumours growth pattern, which in turn is
influenced by expressed proteoglycans.
In this thesis work, we aim to improve the possibilities to diagnose malignant
mesothelioma by combining biomarkers and by identifying new ones. We also
investigate tumour driving mechanisms with focus on one of these suggested
biomarkers, the cell-bound proteoglycan syndecan-1.
We were able to construct a diagnostic two-step model based on biomarkers in patient
material. By implementing a cut-off level and thereafter focusing on unresolved patients
we combined hyaluronan and N-ERC/mesothelin (paper I), which significantly increased
the diagnostic accuracy for malignant mesothelioma. To further improve diagnosis, we
used mass spectrometry to find new biomarkers. We identified and validated galectin-1,
which was excellent in discriminating mesotheliomas from adenocarcinomas (paper II).
In the same study, we were also the first to describe aldo-keto reductase 1B10 as a
novel prognostic mesothelioma biomarker.
Syndecan-1 has been indicated as a marker for carcinomas. In paper I we describe how
higher levels of syndecan-1 indicate the presence of a carcinoma over a mesothelioma.
This was verified in paper II when syndecan-1 was identified as downregulated in fluids
from mesothelioma patients compared to lung cancer patients. Paper III and paper IV
focus on this proteoglycan.
Malignant cell lines transfected with syndecan-1 and various truncated forms of
syndecan-1 affected adhesion and migration, which are key features of cancer invasion
(paper III). The results showed a domain- and cell type specific effect on the cells’
motility. Regulating syndecan-1 levels and analysing the global gene expression of
mesothelioma cells made it evident that this proteoglycan has a strong influence on
transforming growth factor β signalling and several growth factor pathways (paper IV).
Links to cell migration and proliferation were furthermore identified, along with
glycosaminoglycan modifying enzymes. These results can shed light on the complex role
of syndecan-1 in invasion and growth of malignant mesenchymal cells.
Taken together, this thesis work describes a complement to conventional mesothelioma
diagnosis and identifies novel biomarkers. Furthermore, the potential biomarker
syndecan-1 was shown to have an effect on cell motility and proliferation. These results
increase our understanding of this aggressive malignancy
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