92 research outputs found
Treatment of melanoma with selected inhibitors of signaling kinases effectively reduces proliferation and induces expression of cell cycle inhibitors
mTOR inhibitor everolimus reduces invasiveness of melanoma cells
The mammalian target of rapamycin (mTOR) plays a key role in several cellular processes: proliferation, survival, invasion,
and angiogenesis, and therefore, controls cell behavior both in health and in disease. Dysregulation of the mTOR signaling
is involved in some of the cancer hallmarks, and thus the mTOR pathway is an important target for the development of a new
anticancer therapy. The object of this study is recognition of the possible role of mTOR kinase inhibitors-everolimus single
and in combination with selected downstream protein kinases inhibitors: LY294002 (PI3 K), U0126 (ERK1/2), GDC-0879
(B-RAF), AS-703026 (MEK), MK-2206 (AKT), PLX-4032 (B-RRAF) in cell invasion in malignant melanoma. Treatment
of melanoma cells with everolimus led to a significant decrease in the level of both phosphorylated: mTOR (Ser2448) and
mTOR (Ser2481) as well as their downstream effectors. The use of protein kinase inhibitors produced a significant decrease
in metalloproteinases (MMPs) activity, as well as diminished invasion, especially when used in combination. The best results
in the inhibition of both MMPs and cell invasiveness were obtained for the combination of an mTOR inhibitor- everolimus
with a B-RAF inhibitor-PLX-4032. Slightly less profound reduction of invasiveness was obtained for the combinations of
an mTOR inhibitor-everolimus with ERK1/2 inhibitor-U126 or MEK inhibitor-AS-703026 and in the case of MMPs
activity decrease for PI3 K inhibitor-LY294002 and AKT inhibitor-MK-2206. The simultaneous use of everolimus or
another new generation rapalog with selected inhibitors of crucial signaling kinases seems to be a promising concept in
cancer treatment
mTOR inhibitor Everolimus-induced apoptosis in melanoma cells
Melanoma is the most aggressive, therapy-resistant skin cancer. The mammalian target of rapamycin (mTOR), the serine/
threonine kinase which integrates both intracellular and extracellular signals, plays a crucial role in coordinating the balance
between the growth and death of cells. The object of this study is a comparison of the influence of mTOR inhibitor everolimus in
the concentration range between 20 nM and 10 μM, used individually and in combination with selected downstream protein
kinases inhibitors: LY294002 (PI3K), U0126 (ERK1/2), AS-703026 (MEK) and MK-2206 (AKT) on the expression of prosurvival proteins: p-Bcl-2 (S70), p-Bcl-2 (T56), Bcl-2, Bcl-xL, Mcl-1, activity of caspase-3, proliferation and induction of
apoptosis in melanoma cells. Current results clearly show that the nanomolar concentration of the mTOR inhibitor everolimus
in combination with the inhibitor of MAP kinase (AS-703026) or AKT kinase (MK-2206) is effective in inducing apoptosis and
reducing proliferation of melanoma cells. The herein research results confirm the hypothesis on the important role of mTOR
signaling in cancer progression, and gives hope that implementation of successful combination of its inhibitors will find
recognition and application in cancer treatment in the near future
Carbohydrate moieties of N-cadherin from human melanoma cell lines
Expression of N-cadherin an adhesion molecule of the cadherin family, in tumor cells is associated with their increased invasive potential. Many studies suggested the role of N-linked oligosaccharides as important factors that contribute to metastasis by influencing tumor cell invasion and adhesion. N-cadherin is a heavily glycosylated protein. We have analysed the carbohydrate profile of this protein synthesized in human melanoma cell lines: WM35 from the primary tumor site and WM239, WM9, and A375 from different metastatic sites. N-cadherin was immunoprecipitated with anti-human N-cadherin polyclonal antibodies. Characterisation of its carbohydrate moieties was carried out by SDS/PAGE electrophoresis and blotting, followed by immunochemical identification of the N-cadherin polypeptides and analysis of their glycans using highly specific digoxigenin or biotin labelled lectins. The positive reaction of N-cadherin from the WM35 cell line with Galanthus nivalis agglutinin (GNA), Datura stramonium agglutinin (DSA) and Sambucus nigra agglutinin (SNA) indicated the presence of high-mannose type glycans and biantennary complex type oligosaccharides with α2-6 linked sialic acid. N-cadherin from WM239, WM9, and A375 cell lines gave a positive reaction with Phaseolus vulgaris leukoagglutinin (L-PHA) and lotus Tetragonolobus purpureas agglutinin (LTA). This indicated the presence of tri- or tetra-antennary complex type glycans with α-fucose. In addition, N-cadherin from WM9 (lymphomodus metastatic site) and A375 (solid tumor metastatic site) contained complex type chains with α2-3 sialic acid (positive reaction with Maackia amurensis agglutinin - MAA). The results demonstrated that N-glycans of N-cadherin are altered in metastatic melanomas in a way characteristic for invasive tumor cells
Integrin linked kinase regulates endosomal recycling of N-cadherin in melanoma cells
Malignant transformation is characterized by a phenotype "switch" from E- to N-cadherin - a major hallmark of
epithelial to mesenchymal transition (EMT). The increased expression of N-cadherin is commonly followed by a
growing capacity for migration as well as resistance to apoptosis. Integrin Linked Kinase (ILK) is a key molecule
involved in EMT and progression of cancer cells. ILK is known as a major signaling mediator involved in cadherin
switch, but the specific mechanism through which ILK modulates N-cadherin expression is still not clear.
Studies were carried out on human melanoma WM793 and 1205Lu cell lines. Expression of proteins was
analyzed using PCR and Western Blot; siRNA transfection was done for ILK. Analysis of cell signaling pathways
was monitored with phospho-specific antibodies. Subcellular localization of protein was studied using the
ProteoExtract Subcellular Kit and Western blot analysis.
Our data show that ILK knockdown by siRNA did suppress N-cadherin expression in melanoma, but only at
the protein level. The ILK silencing-induced decrease of N-cadherin membranous expression in melanoma
highlights the likely crucial role of ILK in the coordination of membrane trafficking through alteration of Rab
expression. It is essential to understand the molecular mechanism of increased N-cadherin expression in cancer
to possibly use it in the search of new therapeutic targets
Integrin-linked kinase regulates cadherin switch in bladder cancer
Cadherin switch is specific of epithelial-mesenchymal transition (EMT) and is closely related to tumor cell invasion. However, the molecular mechanism that promotes the phenotypic changes remains unclear and elusive. We found that integrin-linked kinase (ILK) is a key factor involved in cadherin switch. The expression and activity of ILK are elevated in a variety of cancers but its mechanisms are not exactly understood. In this report, we studied the role and mechanism of ILK in EMT of human bladder cancer. We showed that silencing of ILK expression by small interfering RNA (siRNA) significantly abolished the nuclear translocation or the presence of markers associated with EMT like Snail, Twist, Zeb, and beta-catenin. ILK knockdown by siRNA suppressed N-cadherin expression and increased re-expression of E-cadherin in bladder cancer cells. We suggest that ILK is a major signaling factor involved in EMT. It is essential to understand the molecular mechanism of EMT in aim to possibly use it in search for new therapeutic targets. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13277-016-5354-x) contains supplementary material, which is available to authorized users
Online visibility of databases compiled by libraries: example of "Pedagog" information system
Artykuł zawiera analizę treści informacji znajdujących się w Internecie, które dotyczą systemu informacyjno-wyszukiwawczego PEDAGOG, tworzonego przez pracowników Biblioteki Głównej Uniwersytetu Opolskiego. Znaczącą rolę w promowaniu i określaniu znaczenia danego serwisu w sieci www, w tym również bibliograficznych baz danych tworzonych przez biblioteki, odgrywają odnośniki od innych stron internetowych. Analiza ma na celu przede wszystkim określenie „ukrytej” obecności PEDAGOGA w Internecie przez ocenę hiperłączy pochodzących od innych stron internetowych, jak również omówienie treści informacji o PEDAGOGU, znajdujących się w sieci www.The paper presents the outcome of the analysis focused on the Internet information related to PEDAGOG
- information system conceived by the Staff of the Main Library of the University of Opole. An important role in promoting and determining the value of a given web service, including bibliographic databases created by libraries, is to attribute to hyperlinks leading to those services from other areas of the web. The analysis is aimed at, first of all, defining the “hidden” e-presence of PEDAGOG by means of assessing the hyperlinks redirecting Internet users to it form other web pages, as well as at describing the content of information about PEDAGOG disseminated throughout the Web
Information and educational-oriented activities of the Reference Department and the promotion of the Main Library of the University of Opole
Ukazano wpływ aktywności Oddziału Informacji Naukowej na kształtowanie pozytywnego wizerunku
Biblioteki Głównej Uniwersytetu Opolskiego. Podkreślono konieczność promocji Biblioteki wśród pracowników wszystkich jednostek Uniwersytetu Opolskiego, a także znaczenie działalności OIN dla promowania Uczelni. Przedstawiono rodzaje działalności, zarówno informacyjną, dydaktyczną i wystawienniczą, w tym szczególne znaczenie szkoleń w edukacji informacyjnej, oraz nieustanne udoskonalanie warsztatu pracy przeznaczonego dla pracowników i użytkowników OIN, zwłaszcza elektronicznych źródeł informacji. Podkreślono znaczenie wiedzy zdobytej w bibliotece w odniesieniu sukcesu przez użytkownika. Nakreślono ewaluację zakresu działań OIN pod względem potrzeb i zainteresowań czytelników. Podkreślono zależność między efektywnością pracy OIN a pozytywnym
odbiorem działalności Biblioteki Głównej UO.The authors present the influence of activities performed by the Reference Department of the Main
Library of the University of Opole on creating positive image of this library. They stress the necessity to promote the library among the employees of the whole university and the role of this particular department in promoting the university. Various kinds of possible activities are presented, including information and educational services as well as exhibitions. The emphasis is laid on information instruction and permanent improving of library resources and facilities supporting librarians and users, particularly electronic sources of information. Furthermore, the authors accent the significance of knowledge gained in the library for users' success and evaluate the scope of activities undertaken by the reference department with regards to its users' needs. The attention is also drawn to relations between the performance of this department and positive reception of the performance of the whole library
Praca zespołowa i współpraca w szkole w ramach pomocy psychologiczno – pedagogicznej: Cel sam w sobie czy sposób na sukces dla każdego ucznia?
Teamwork and cooperation in school within psychological-pedagogical assistance: The goal itself or a way for each student to achieve success Cooperation appears to be one of the priorities, an emphasized part of strategy in different countries, including Poland (e.g. strategy “Poland 2030. Development Challenges”), as a foundation of capital development of the state. The priority of cooperation is refl ected also within the educational reform, especially in the new approved law regulations underlining importance of team work devoted to psychological-pedagogical assistance. First attempts of implementation of the new regulations have been undertaken in a pilot project conducted by the Ministry of National Education in 2011 focused on elementary, primary and secondary schools. It became the subject of a qualitative research conducted by the Institute for Educational Research. Key findings relates to the cooperation and organization of work in teams as well as to disclose difficulties and ways to overcome them. Do the undertaken efforts at school can bear name of a full collaboration? What are the diffi culties associated with organising of work in teams aimed at students’ needs diagnosis? We will try to find an answer to these questions in the present article
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