51 research outputs found

    Intratumoral functional heterogeneity and chemotherapy

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    Intratumoral heterogeneity including genetic and nongenetic mechanisms refers to biological differences amongst malignant cells originated within the same tumor. Both, cell differentiation hierarchy and stochasticity in gene expression and signaling pathways may result in phenotypic differences of cancer cells. Since a tumor consists of cancer cell clones that display distinct behaviours, changes in clonal proliferative behavior may also contribute to the phenotypic variability of tumor cells. There is a need to reveal molecular actions driving chemotherapeutic resistance in colon cancer cells. In general, it is widely hypothesized that therapeutic resistance in colorectal cancer is a consequence of the preferential survival of cancer stem cells. However, recent data regarding colorectal cancer suggest that resistance to anticancer therapy and post-therapeutic tumor reappearence could be related to variations of clonal dynamics. Understanding the interaction of genetic and nongenetic determinants influencing the functional diversity and therapy response of tumors should be a future direction for cancer research

    Primer immunhiány és autoimmun betegségek

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    Absztrakt: A primer immunhiányos betegségek a természetes és az adaptív immunrendszer elemeit érintő, genetikailag heterogén immunológiai rendellenességek. A primer immunhiányban szenvedő betegek nemcsak visszatérő fertőzésekre, de noninfektív kórállapotokra, így gyulladásos vagy granulomatosus eltérésekre, lymphoproliferativ és szolid daganatos megbetegedésekre, autoinflammatiós állapotokra, valamint a legkülönfélébb autoimmun kórformákra is hajlamosabbak. Az elsődleges immunhiány és az autoimmunitás paradoxonnak tűnő együttes megjelenése valódi kihívást jelent az immunhiányos betegek autoimmun szövődményeinek felismerésében. A primer immunhiányos állapotok hátterében általában egy vagy több, az immunregulációban és/vagy az immuntolerancia kialakításában kulcsszerepet játszó gén mutációja áll. A szerteágazó immunológiai rendellenességek, a kompenzatorikus, túlzott mértékű krónikus gyulladásos válaszreakció és a következményes szövetkárosodás együttese végső soron szerv-, sejtspecifikus vagy szisztémás autoimmun betegségek kialakulásához vezet. Számos primer immunhiányos kórképet különböző, sajátos autoimmun manifesztáció jellemez. A jelen összefoglaló célja a primer immunhiányos állapotokban megjelenő autoimmun kórképek, valamint az immunrendszeri rendellenességek alapjául szolgáló molekuláris és celluláris mechanizmusok áttekintése. A dolgozat végén ismertetett eset rávilágít arra, hogy immunhiányos állapotokban az autoimmun betegségek felismerése, illetve a dominálóan autoimmun kórkép formájában induló fenotípusoknál az immunhiány kórismézése egyaránt kihívást jelenthet. Orv Hetil. 2018; 159(23): 908–918. | Abstract: Primary immunodeficiencies consist of a group of genetically heterogeneous immune disorders affecting distinct elements of the innate and adaptive immune system. Patients with primary immunodeficiency are more prone to develop not only recurrent infections, but non-infectious complications, like inflammatory or granulomatous conditions, lymphoproliferative and solid malignancies, autoinflammatory disorders, and a broad spectrum of autoimmune diseases. The concomitant appearance of primary immunodeficiency and autoimmunity appears to be rather paradoxical, therefore making the diagnosis of immunodeficiency patients with autoimmune complications challenging. Mutations of one or more genes playing a fundamental role in immunoregulation and/or immune tolerance network are thought to be responsible for primary immunodeficiencies. The diverse immunological abnomalities along with the compensatory and excessive sustained inflammatory response result in tissue damage and finally in manifestation of organ-, cell-specific or systemic autoimmune diseases. Several forms of primary immunodeficiency disorders are characterized by a variety of specific autoimmune phenomena. This overview addresses the spectrum of autoimmune diseases associated with primary immunodeficiencies, and explores the molecular and cellular mechanisms underlying abnormalities of the immune system. The case presented finally highlights that both the recognition of autoimmune diseases in association with immunodeficiencies and the diagnosis of immunodefiency in those phenotypes with predominant autoimmunity could be challenging. Orv Hetil. 2018; 159(23): 908–918

    Contribution of TLR signaling to the pathogenesis of colitis-associated cancer in inflammatory bowel disease

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    In the intestine a balance between proinflammatory and repair signals of the immune system is essential for the maintenance of intestinal homeostasis. The innate immunity ensures a primary host response to microbial invasion, which induces an inflammatory process to localize the infection and prevent systemic dissemination of pathogens. The key elements of this process are the germline encoded pattern recognition receptors including Toll-like receptors (TLRs). If pathogens cannot be eliminated, they may elicit chronic inflammation, which may be partly mediated via TLRs. Additionally, chronic inflammation has long been suggested to trigger tissue tumorous transformation. Inflammation, the seventh hallmark of cancer, may affect all phases of tumor development, and evade the immune system. Inflammation acts as a cellular stressor and may trigger DNA damage or genetic instability. Furthermore, chronic inflammation can provoke genetic mutations and epigenetic mechanisms that promote malignant cell transformation. Colorectal cancers in inflammatory bowel disease patients are considered typical examples of inflammation-related cancers. Although data regarding the role of TLRs in the pathomechanism of cancer-associated colitis are rather conflicting, functionally these molecules can be classified as ”largely antitumorigenic” and ”largely pro-tumorigenic” with the caveat that the underlying signaling pathways are mainly context (i.e., organ-, tissue-, cell-) and ligand-dependent

    Epithelial toll-like receptor 9 signaling in colorectal inflammation and cancer: Clinico-pathogenic aspects.

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    Toll-like receptors (TLRs) recognize specific motifs which are frequently present in bacteria, fungi, prokaryotes and viruses. Amongst TLRs, TLR9 can be activated by such bacterial or viral DNA fragments, immunoglobulin-DNA complexes or synthetic oligonucleotides, which all contain unmethylated cytosine-guanine nucleotide sequences (CpGs). Emerging data indicate that TLR9 signaling has a role in, and may influence, colorectal carcinogenesis and colonic inflammation. CpGs are classified into three groups according to their influence on both the antigen-specific humoral- and cellular immunity, and the production of type 1 interferons and proinflammatory cytokines. TLR9 activation via CpGs may serve as a new therapeutic target for several cancerous and various inflammatory conditions. Due to its probable anti-cancer effects, the application possibilities of TLR9-signaling modulation may be extremely diverse even in colorectal tumors. In this review we aimed to summarize the current knowledge about TLR-signaling in the pathogenesis and therapy of inflammatory bowel diseases and colorectal cancer. Due to the species-specific differences in TLR9 expression, however, one must be careful in translating the animal model data into the human system, because of the differences between CpG-oligodeoxynucleotide-responsive cells. TLR9 agonist DNA-based immunomodulatory sequences could also represent a promising therapeutic alternative in systemic inflammatory conditions and chronic colonic inflammations as their side effects are not significant

    Altered Immune Regulation in Type 1 Diabetes

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    Research in genetics and immunology was going on separate strands for a long time. Type 1 diabetes mellitus might not be characterized with a single pathogenetic factor. It develops when a susceptible individual is exposed to potential triggers in a given sequence and timeframe that eventually disarranges the fine-tuned immune mechanisms that keep autoimmunity under control in health. Genomewide association studies have helped to understand the congenital susceptibility, and hand-in-hand with the immunological research novel paths of immune dysregulation were described in central tolerance, apoptotic pathways, or peripheral tolerance mediated by regulatory T-cells. Epigenetic factors are contributing to the immune dysregulation. The interplay between genetic susceptibility and potential triggers is likely to play a role at a very early age and gradually results in the loss of balanced autotolerance and subsequently in the development of the clinical disease. Genetic susceptibility, the impaired elimination of apoptotic β-cell remnants, altered immune regulatory functions, and environmental factors such as viral infections determine the outcome. Autoreactivity might exist under physiologic conditions and when the integrity of the complex regulatory process is damaged the disease might develop. We summarized the immune regulatory mechanisms that might have a crucial role in disease pathology and development

    Association of self-DNA mediated TLR9-related gene-, DNA methyltransferase and cytokeratin protein expression alterations in HT29-cells to DNA fragment length and methylation status

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    To understand the biologic role of self-DNA bound to Toll-like Receptor 9 (TLR9), we assayed its effect on gene and methyltransferase expressions and cell differentiation in HT29 cells. HT29 cells were incubated separately with type-1 (normally methylated/nonfragmented), type-2 (normally methylated/fragmented), type-3 (hypermethylated/nonfragmented), or type-4 (hypermethylated/fragmented) self-DNAs. Expression levels of TLR9-signaling and proinflammatory cytokine-related genes were assayed by qRT-PCR. Methyltransferase activity and cell differentiation were examined by using DNA methyltransferase (DNMT1, -3A, -3B) and cytokeratin (CK) antibodies. Treatment with type-1 DNA resulted in significant increase in TLR9 expression. Type-2 treatment resulted in the overexpression of TLR9-related signaling molecules (MYD88A, TRAF6) and the IL8 gene. In the case of type-3 treatment, significant overexpression of NFkB, IRAK2, and IL8 as well as downregulation of TRAF6 was detected. Using type-4 DNA, TRAF6 and MYD88A gene expression was upregulated, while MYD88B, IRAK2, IL8, and TNFSF10 were all underexpressed. CK expression was significantly higher only after type-1 DNA treatment. DNMT3A expression could also be induced by type-1 DNA treatment. DNA structure may play a significant role in activation of the TLR9-dependent and even independent proinflammatory pathways. There may be a molecular link between TLR9 signaling and DNMT3A. The mode of self-DNA treatment may influence HT29 cell differentiation

    Miscellanea. Folyóirat-referátumok. Könyvismertetés

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    Kardiológia. A statinok használata és a diabetes kialakulásának kockázata: retrospektív kohorszvizsgálat (Use of statins and the risk of incident diabetes: a retrospective cohort study) Olotu, B. S., Shepherd, M. D., Novak, S., et al. (Department of Pharmacy Practice, University of Kansas School of Pharmacy, 2010 Becker Dr., Lawrence, KS, 66047, Amerikai Egyesült Államok; e-mail: [email protected]): Am. J. Cardiovasc. Drugs, 2016, 16 (5), 377–390. | Pulmonológia. Az inhalációs kortikoszteroidok csökkenthetik az osteoporosist COPD-s nőbetegeknél (Inhaled corticosteroids can reduce osteoporosis in female patients with COPD) Liu, S. F., Kuo, H. C., Liu, G. H., et al. (Levelező szerző: Ho-Chang Kuo, Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, No 123, Ta-Pei Road, Niaosong District, Kaohsiung 833, Taiwan, Kínai Köztársaság; e-mail: [email protected]): Int. J. Chron. Obstruct. Pulmon. Dis., 2016, 11, 1607–1614. | Radiológia. A vena cava inferior képalkotó vizsgálata (Imaging evaluation of the inferior vena cava) Smillie, R. P., Shetty, M., Boyer, A. C., et al. (Department of Diagnostic Radiology, Beaumont Health System, Beaumont Hospital Royal Oak, 3601 W 13 Mile Rd, Royal Oak, MI 48073, Amerikai Egyesült Államok): Radiographics, 2015, 35 (2), 578–592. | Szülészet-nőgyógyászat. Ectopiás terhesség incarceralt méhkürtben (Ectopic pregnancy in an incarcerated fallopian tube) Lin, F., Yue, D. X., Quinn, M. J., et al. (Department of Obstetrics and Gynecology, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Kína): Am. J. Obstet. Gynecol., 2015, 213 (2), 244.e1–244.e2. | Joseph G. Sinkovics: RNA/DNA and Cancer Springer International Publishing, Switzerland, 2016 Hardcover ISBN 978-3-319-22278-3 DOI: 10.1007/978-3-319-22279-0 eBook ISBN 978-3-319-22279-

    Connexin 43 Communication Channels in Follicular Dendritic Cell Development and in Follicular Lymphomas

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    Follicular dendritic cells (FDC) show homo- and heterocellular metabolic coupling through connexin 43 (Cx43) gap junctions and support B cell selection and maturation in germinal centers. In follicular lymphomas B cells escape apoptosis while FDC develop abnormally. Here we tested Cx43 channels in reactive FDC development and follicular lymphomas. In culture, the treatment of FDC-B cell clusters (resembling to “ ex vivo ” germinal centers) with Gap27 peptide, mimicking the 2nd extracellular loop of Cx43 protein, significantly impaired FDC-B cell cluster formation and cell survival. In untreated cultures of intact clusters, cell proliferation showed a moderate reduction. In tissues, Cx43 protein levels run parallel with the density of FDC both in reactive germinalcentersandinmalformedfolliclesoffollicularlymphomasandshowedstrongupregulationinnewlygeneratedand/or degrading bi-/multinuclear FDC of rudimentary processes. However, the inverse correlation between Cx43 expression and B cell proliferation seen in reactive germinal centers was not detected in follicular lymphomas. Furthermore, Cx43 levels were not associated with either lymphoma grade or bone marrow involvement. Our results suggest that Cx43 channels are critical in FDC and “ ex vivo ” germinal center development and in the persistence of FDC in follicular lymphomas but do not affect tumor progression

    Idiopathiás retroperitonealis fibrosis : Buktatók és kihívások – két kórlefolyás tapasztalatai = Idiopathic retroperitoneal fibrosis : Pitfalls and challenges – experience with two cases

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    A retroperitonealis fibrosis a retroperitoneum idült, nem specifikus gyulladása; az esetek 75%-ában idiopathiás. Fibrosis jellemzi, amely valószínűleg autoimmun gyulladást követően alakul ki. A kiváltó tényező nem ismert, de az atherosclerosis szerepét feltételezik. A jellegtelen klinikai tünetek, laboratóriumi eltérések miatt gyakran hosszú idő telik el a kórisméig, ezért sok esetben már szövődmények megjelenésével találkozunk. A gyógyszeres kezelés – a szövődmények sebészi vagy urológiai megoldását követően – az immunszuppresszív terápia. A kortikoszteroid a leggyakrabban alkalmazott készítmény, az optimális dózis és a kezelés időtartama nem teljesen egyértelmű. Kiújulás miatt az esetek többségében ismételt vagy a szteroiddózis csökkentését lehetővé tevő kezelés szükséges. A kezelésre adott válasz megjósolására, a kortikoszteroidigény megítélésére vagy a betegség visszatérésének előrejelzésére alkalmas tényezők nem ismertek. A szerzők két beteg kórtörténetét ismertetik – bemutatva a kórisme megállapításának nehézségeit. Orv. Hetil., 2011, 152, 1818–1826. | Retroperitoneal fibrosis is the chronic, nonspecific inflammation of the retroperitoneum. About 75% of the cases are idiopathic. The pathomechanism of the disorder is not clearly defined. Autoimmune inflammation and secondary fibrosis are the main suspected mechanisms against an unknown factor possibly related to atherosclerosis. Symptoms and laboratory parameters are nonspecific which make the diagnosis difficult. At the time of the diagnosis complications are often present. After the urological and surgical management of the complications, the aim of the medical treatment is immunosuppression. Corticosteroids are usually used for treatment, although the optimal dosage and the duration of the treatment are not known. After therapy cessation relapse may occur, needing repeated steroid therapy or addition of steroid sparing drugs. Predicting factors for treatment response, corticosteroid demand or relapse are not known. Authors review the medical history of two patients with retroperitoneal fibrosis and discuss diagnostic difficulties of this disorder. Orv. Hetil., 2011, 152, 1818–1826
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