571 research outputs found

    H3 histamine receptor-mediated activation of protein kinase calpha inhibits the growth of cholangiocarcinoma in vitro and in vivo

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    Histamine regulates functions via four receptors (HRH1, HRH2, HRH3, and HRH4). The D-myo-inositol 1,4,5-trisphosphate (IP(3))/Ca(2+)/protein kinase C (PKC)/mitogen-activated protein kinase pathway regulates cholangiocarcinoma growth. We evaluated the role of HRH3 in the regulation of cholangiocarcinoma growth. Expression of HRH3 in intrahepatic and extrahepatic cell lines, normal cholangiocytes, and human tissue arrays was measured. In Mz-ChA-1 cells stimulated with (R)-(alpha)-(-)-methylhistamine dihydrobromide (RAMH), we measured (a) cell growth, (b) IP(3) and cyclic AMP levels, and (c) phosphorylation of PKC and mitogen-activated protein kinase isoforms. Localization of PKC alpha was visualized by immunofluorescence in cell smears and immunoblotting for PKC alpha in cytosol and membrane fractions. Following knockdown of PKC alpha, Mz-ChA-1 cells were stimulated with RAMH before evaluating cell growth and extracellular signal-regulated kinase (ERK)-1/2 phosphorylation. In vivo experiments were done in BALB/c nude mice. Mice were treated with saline or RAMH for 44 days and tumor volume was measured. Tumors were excised and evaluated for proliferation, apoptosis, and expression of PKC alpha, vascular endothelial growth factor (VEGF)-A, VEGF-C, VEGF receptor 2, and VEGF receptor 3. HRH3 expression was found in all cells. RAMH inhibited the growth of cholangiocarcinoma cells. RAMH increased IP(3) levels and PKC alpha phosphorylation and decreased ERK1/2 phosphorylation. RAMH induced a shift in the localization of PKC alpha expression from the cytosolic domain into the membrane region of Mz-ChA-1 cells. Silencing of PKC alpha prevented RAMH inhibition of Mz-ChA-1 cell growth and ablated RAMH effects on ERK1/2 phosphorylation. In vivo, RAMH decreased tumor growth and expression of VEGF and its receptors; PKC alpha expression was increased. RAMH inhibits cholangiocarcinoma growth by PKC alpha-dependent ERK1/2 dephosphorylation. Modulation of PKC alpha by histamine receptors may be important in regulating cholangiocarcinoma growth. (Mol Cancer Res 2009;7(10):1704-13

    Inhibition of mapk signalling promotes cell cycle arrest and sensitises intrahepatic cholangiocarcinoma cells to chemotherapy

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    Introduction: Intrahepatic cholangiocarcinoma (ICC) is the second most common primary hepatic malignancy, accounting for approximately 15% of cases of primary liver cancer. Although new treatments have increased survival for many other cancers, including the more common primary hepatocellular carcinoma, treatment strategies and survival for patients with ICC have seen little improvement. Our previous studies suggest that the mitogen-activated protein kinase (MAPK) signalling plays a central role in the regulation of cell proliferation in human ICC. However the molecular mechanisms are poorly understood. In this study, we aim to explore whether inhibition of the MAPK pathway and its downstream effectors enhances the sensitisation of ICC cells to the chemotherapeutic agent cisplatinum. Method: We used a combinatorial approach of immunohistochemical and gene expression analyses to investigate the expression of MAPK-related genes in ICC tumours. Furthermore, by using in-vitroand in-vivoanalyses we have characterised the function of a novel MAPK downstream effector in ICC cells. Results: The expression of MAPK signalling was determined by immunohistochemical staining in tumour samples from a cohort of 14 ICC patients. High expression of phospho-activated MAPK was observed in 71.4% (10/14) of ICC cases as compared with surrounding nontumour tissue. Likewise, expression of JDP, a downstream effector of the MAPK signalling, was scored as high intensity in 64.3% (9/14). Strikingly, elevated expression of JDP transcripts was also observed in two independent cohorts of human ICC (n = 149 and n = 109 per group, respectively) compared to surrounding normal liver tissue. Consistent with the in-vivo analyses of human samples, immunoblotting analyses showed constitutive activation of MAPK and expression of JDP in ICC-derived cells (i.e. SG231, CCLP-1 and HuCCT1). Using loss-of-function analyses, we demonstrates that knockdown of JDP in ICC-derived cells resulted in cell cycle arrest and reduced expression of cell cycle regulators (i.e. cyclins), and had minimal effect on apoptosis. Chemical inhibition of JDP significantly sensitises ICC-derived cells to cisplatinum (P < 0.001). Conclusion: These results demonstrate that enhanced activation of MAPK signalling is important for ICC cell proliferation and suggest that targeting its downstream effectors is a potential therapeutic strategy for ICC

    Intracellular distribution of Tankyrases as detected by multicolor immunofluorescence techniques

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    Poly(ADP-ribose) polymerases are a family of enzymes that catalyze the conversion of NAD+ into ADP-ribose. Among them, Tankyrases have been found to bind to centrosome, mitotic spindle and microsome proteins, in the cytoplasm, and to telomeres in the nucleus, where they play a relevant role in telomere metabolism. However, their precise intracellular localization during interphase has not been so far fully elucidated. We investigated this aspect in situ by double immunofluorescence experiments using antibodies recognizing Tankyrases 1–2 or other proteins residing in specific organelles (Golgi apparatus, mitochondria, lysosomes, endoplasmic reticulum). We used HeLa cells as a model system in vitro, before and after treatment with either actinomycin D or etoposide, to also investigate the possible relocation of Tankyrases during apoptosis. We observed that Tankyrases are distributed both in the nucleus and in the cytoplasm; in this latter compartment, they were found to colocate with the Golgi apparatus but never with the mitochondria; a pool of Tankyrases also colocates with the endoplasmic reticulum and lysosomes. Interestingly, in cells with clear signs of apoptosis, Tankyrases were detectable in the cytoplasmic blebs: this suggests that they are not massively cleaved during apoptosis and persist in the largely heterogeneous apoptotic remnants which are known to contain components of cytoplasmic and nuclear origin

    Nuclear localization of phosphorylated c-Myc protein in human tumor cells.

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    Using immunocytochemical techniques at light and electron microscopy, we analysed the distribution of phosphorylated c-Myc in actively proliferating human HeLa cells. The distribution pattern of c-Myc was also compared with those of other ribonucleoprotein (RNP)-containing components (PANA, hnRNP-core proteins, fibrillarin) or RNP-associated nuclear proteins (SC-35 splicing factor). Our results provide the first evidence that phosphorylated c-Myc accumulates in the nucleus of tumor cells, where it colocalizes with fibrillarin, both in the nucleolus and in extranucleolar structures

    AN ANALYSIS OF SYMBOLS FROM GUA CEREMONY OF OLAIA SOCIETY

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    Gua Ceremony is part of Olaia tradition and an event which is interesting to analyze because there are many kinds of symbols used in it. Gua ceremony is not separated from language. By using language, we can express our thought, idea, emotion, and feeling, because language is an important aspect of human life and social communication among the members of society. It is interesting to study Gua ceremony linguistically, especially in semantic. Therefore, the researcher is interested in studying this problem by formulating five researcher problems such as: how does the process of implementation of Gua ceremony on Olaia village, sub-district Aesesa, District Nagekeo,what are the symbols and symbols meaning on Olaia village, sub-district Aesesa, District Nagekeo. What are functions of Gua ceremony on Olaia village, sub-district Aesesa, District Nagekeo, and What are values appeared from Gua ceremony on Olaia village, sub-district Aesesa, District Nagekeo?&nbsp;This study has two significances of the study,&nbsp; theoretically and practically. Theoretically, the result of this study will give the description about the symbols used in Gua ceremony. Practically, the researcher hopes this research is useful to enrich the description of Gua ceremony and as additional knowledge for people or student both from Nagekeo or others.&nbsp; The research of this thesis is qualitative research. It is intended to describe about the symbols, and also their meaning used in Gua ceremony. Besides the researcher himself as the key instruments, the instruments used in this study are documentation, observation, and interview. From the result of this study, it was obvious that Gua ceremony used some symbols. And every symbol has its own meaning

    Conditional Genetic Elimination of Hepatocyte Growth Factor in Mice Compromises Liver Regeneration after Partial Hepatectomy

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    Hepatocyte growth factor (HGF) has been shown to be indispensable for liver regeneration because it serves as a main mitogenic stimulus driving hepatocytes toward proliferation. We hypothesized that ablating HGF in adult mice would have a negative effect on the ability of hepatocytes to regenerate. Deletion of the HGF gene was achieved by inducing systemic recombination in mice lacking exon 5 of HGF and carrying the Mx1-cre or Cre-ERT transgene. Analysis of liver genomic DNA from animals 10 days after treatment showed that a majority (70-80%) of alleles underwent cre-induced genetic recombination. Intriguingly, however, analysis by RT-PCR showed the continued presence of both unrecombined and recombined forms of HGF mRNA after treatment. Separation of liver cell populations into hepatocytes and non-parenchymal cells showed equal recombination of genomic HGF in both cell types. The presence of the unrecombined form of HGF mRNA persisted in the liver in significant amounts even after partial hepatectomy (PH), which correlated with insignificant changes in HGF protein and hepatocyte proliferation. The amount of HGF produced by stellate cells in culture was indirectly proportional to the concentration of HGF, suggesting that a decrease in HGF may induce de novo synthesis of HGF from cells with residual unrecombined alleles. Carbon tetrachloride (CCl4)-induced regeneration resulted in a substantial decrease in preexisting HGF mRNA and protein, and subsequent PH led to a delayed regenerative response. Thus, HGF mRNA persists in the liver even after genetic recombination affecting most cells; however, PH subsequent to CCl4 treatment is associated with a decrease in both HGF mRNA and protein and results in compromised liver regeneration, validating an important role of this mitogen in hepatic growth. © 2013 Nejak-Bowen et al

    Gallstone and gallbladder disease: biliary tract and cholangiopathies

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    : Cholestatic liver diseases are named primarily due to the blockage of bile flow and buildup of bile acids in the liver. Cholestasis can occur in cholangiopathies, fatty liver diseases, and during COVID-19 infection. Most literature evaluates damage occurring to the intrahepatic biliary tree during cholestasis; however, there may be associations between liver damage and gallbladder damage. Gallbladder damage can manifest as acute or chronic inflammation, perforation, polyps, cancer, and most commonly gallstones. Considering the gallbladder is an extension of the intrahepatic biliary network, and both tissues are lined by biliary epithelial cells that share common mechanisms and properties, it is worth further evaluation to understand the association between bile duct and gallbladder damage. In this comprehensive article, we discuss background information of the biliary tree and gallbladder, from function, damage, and therapeutic approaches. We then discuss published findings that identify gallbladder disorders in various liver diseases. Lastly, we provide the clinical aspect of gallbladder disorders in liver diseases and ways to enhance diagnostic and therapeutic approaches for congruent diagnosis. © 2023 American Physiological Society. Compr Physiol 13:4909-4943, 2023

    Early, incomplete, or preclinical autoimmune systemic rheumatic diseases and pregnancy outcome

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    OBJECTIVE: To evaluate the impact of preclinical systemic autoimmune rheumatic disorders on pregnancy outcome. METHODS: In this longitudinal cohort study, patients were enrolled during the first trimester of pregnancy if they reported having had connective tissue disorder symptoms, were found to be positive for circulating autoantibodies, and on clinical evaluation were judged to have a preclinical or incomplete rheumatic disorder. The incidence of fetal growth restriction (FGR), preeclampsia, and adverse pregnancy outcomes in patients with preclinical rheumatic disorders was compared with that in selected controls, after adjustment for confounders by penalized logistic regression. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: Of 5,232 women screened, 150 (2.9%) were initially diagnosed as having a suspected rheumatic disorder. After a mean\u2009\ub1\u2009SD postpartum follow-up of 16.7\u2009\ub1\u20095.5 months, 64 of these women (42.7%) had no clinically apparent rheumatic disease and 86 (57.3%) had persistent symptoms and positive autoantibody results, including 10 (6.7%) who developed a definitive rheumatic disease. The incidences of preeclampsia/FGR and of small for gestational age (SGA) infants were 5.1% (23 of 450) and 9.3% (42 of 450), respectively, among controls, 12.5% (8 of 640) (OR 2.7 [95% CI 1.1-6.4]) and 18.8% (12 of 64) (OR 2.2 [95% CI 1.1-4.5]), respectively, among women with no clinically apparent disease, and 16.3% (14 of 86) (OR 3.8 [95% CI 1.9-7.7]) and 18.6% (16 of 86) (OR 2.3 [95% CI 1.2-4.3]), respectively, among those with persisting symptoms at follow-up. Mean\u2009\ub1\u2009SD umbilical artery Doppler pulsatility indices were higher among women with no clinically apparent disease (0.95\u2009\ub1\u20090.2) and those with persisting symptoms (0.96\u2009\ub1\u20090.21) than in controls (0.89\u2009\ub1\u20090.12) (P\u2009=\u20090.01 and P\u2009&lt;\u20090.001, respectively). CONCLUSION: In our study population, preclinical rheumatic disorders were associated with an increased risk of FGR/preeclampsia and SGA. The impact of these findings and their utility in screening for FGR/preeclampsia need to be confirmed in population studies
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