42 results on '"Genze F"'
Search Results
2. Photodynamic therapy of experimental colonic tumours with 5-aminolevulinic-acid-induced endogenous porphyrins
- Author
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Orth, K., König, K., Genze, F., and Rück, A.
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- 1994
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3. Biokompatibilität von CO-Alkene-Polymeren mit aus urologischen Geweben isolierten primären Zellen und undifferenzierten Zellen
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Bartsch, G., Malinova, V., Genze, F., Volkmer, B.E., Simon, J., Eggel, M., Hautmann, R.E., and Rieger, B.
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- 2007
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4. Methylene blue mediated photodynamic therapy in experimental colorectal tumors in mice
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Orth, K, Beck, G, Genze, F, and Rück, A
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- 2000
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5. Ureterersatz durch ein „tissue-engineertes“ Veneninterponat
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Brito-Juarez, M., Engel, O., De Petriconi, R., Volkmer, B.E., Simon, J., DeCoppi, P., Genze, F., Eggel, M., Chaiklieng, S., Hautmann, R.E., and Bartsch, G.
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- 2007
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6. Sodium butyrate and tributyrin induce in vivo growth inhibition and apoptosis in human prostate cancer.
- Author
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Kuefer, R., Hofer, M.D., Altug, V., Zorn, C., Genze, F., Kunzi-Rapp, K., Hautmann, R.E., and Gschwend, J.E.
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BUTYRIC acid ,PROSTATE cancer ,TUMORS ,CANCER ,ONCOLOGY - Abstract
Histone deacetylase inhibitors (HDACs) are known to exhibit antiproliferative effects on various carcinoma cells. In this study, the in vivo efficiency of two HDACs, sodium butyrate and tributyrin, on prostate cancer growth inhibition were investigated. To gain an insight into the possible underlying pathways, cell culture experiments were performed focusing on the expression of p21, Rb and c-myc. For in vivo testing, prostate cancer cell lines (PC3 and TSU-Pr1) were seeded on the chorioallantois membrane (CAM) and implanted in a xenograft model using nude mice. Standard Western blot analysis was performed for protein expression of p21, Rb and c-myc in HDAC-treated vs untreated prostate cancer cells. Both sodium butyrate and tributyrin had a considerable treatment effect on microtumours on the chicken egg at already very low concentrations of 0.1?mM. Tributyrin-treated tumours showed the strongest effect with 38% apoptotic nuclei in the prostate cancer cell line PC3. In the mouse model, there was almost no difference between sodium butyrate and tributyrin. In untreated animals the tumours were almost double the size 4 weeks after implantation. Tumours of the treatment groups had a significantly lower percentage of Ki-67-positive-stained nuclei. As demonstrated by Western blot analysis, these effects seem to be independent of p53 status and a pathway via p21-Rb-c-myc is possibly involved. In this study we have demonstrated a substantial in vivo treatment effect, which can be induced by the application of sodium butyrate or the orally applicable tributyrin in human prostate cancer. The given results may provide the rationale to apply these drugs in well-controlled clinical trials in patients being at high risk of recurrence after specific therapy or in patients with locally or distant advanced prostate cancer.British Journal of Cancer (2004) 90, 535-541. doi:10.1038/sj.bjc.6601510 www.bjcancer.com [ABSTRACT FROM AUTHOR]
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- 2004
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7. Expression of MTA1 promotes motility and invasiveness of PANC-1 pancreatic carcinoma cells.
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Hofer, M.D., Menke, A., Genze, F., Gierschik, P., and Giehl, K.
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PANCREATIC cancer ,METASTASIS ,TUMORS ,CANCER ,ONCOLOGY - Abstract
The human metastasis-associated protein 1 (MTA1) is a constituent of the nucleosome-remodelling and -deacetylation complex. Its expression has been correlated with the invasion and metastasis of epithelial neoplasms. To address the functional consequences of MTA1 expression in pancreatic carcinoma cells, we have established PANC-1 pancreatic carcinoma cells that stably express MTA1 as an enhanced green fluorescent fusion protein (EGFP-MTA1). Here, we demonstrate that heterologous expression of EGFP-MTA1 markedly enhanced the cellular motility and the invasive penetration of epithelial barriers by the cells. Expression of EGFP-MTA1 had no effect on substrate-independent growth, but reduced substrate-dependent cell proliferation. In addition, the organisation of the cytokeratin filament system and the localisation of the actin cytoskeleton-associated protein IQGAP1 were distinctly altered in EGFP-MTA1-expressing cells. These results indicate that enhanced expression of MTA1 promotes the acquisition of an invasive, metastatic phenotype, and thus enhances the malignancy of pancreatic adenocarcinoma cells by modulation of the cytoskeleton. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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8. Photodynamic activity of liposome-delivered Cd-texaphyrin using tumor-bearing nude mice.
- Author
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König, Karsten, Genze, Felicitas, Miller, Kurt, Rück, Angelika, Reich, Ella, Repassy, Denes, König, K, Genze, F, Miller, K, Rück, A, Reich, E, and Repassy, D
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- 1993
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9. ANTI-INFLAMMATORY AND ANTI-ATHEROGENIC EFFECTS OF THE NF-KAPPAB INHIBITOR ACETYL-11-KETO-BETA-BOSWELLIC ACID IN LPS-CHALLENGED APOE-/- MICE
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Cuaz-perolin, C., Billiet, L., Bauge, E., Copin, C., Scott-Algara, D., Genze, F., Buchele, B., Syrovets, T., Simmet, T., and Rouis, M.
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- 2008
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10. ANTAGONISTIC EFFECTS OF SODIUM BUTYRATE AND N-(4- HYDROXYPHENYL)RETINAMIDE ON PROSTATE CANCER
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Kuefer, R., Genze, F., Zugmaier, W., Rinnab, L., Hautmann, R.E., and Buechele, B.
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- 2008
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11. 260 POSTER A novel paradigm for apoptosis-based therapy of pancreatic cancer: sensitizer/inducer concept of XIAP inhibitors combined with TRAIL
- Author
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Vogler, M., Walczak, H., Stadel, D., Genze, F., Möller, P., Simmet, T., Debatin, K.M., and Fulda, S.
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- 2008
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12. 824 ANTAGONISTIC EFFECTS OF SODIUM BUTYRATE AND N-(4- HYDROXYPHENYL)RETINAMIDE ON PROSTATE CANCER
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Kuefer, R., Genze, F., Zugmaier, W., Rinnab, L., Hautmann, R.E., and Buechele, B.
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- 2008
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13. A New CYP2E1 Inhibitor, 12-Imidazolyl-1-dodecanol, Represents a Potential Treatment for Hepatocellular Carcinoma.
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Diesinger T, Lautwein A, Bergler S, Buckert D, Renz C, Dvorsky R, Buko V, Kirko S, Schneider E, Kuchenbauer F, Kumar M, Günes C, Genze F, Büchele B, Simmet T, Haslbeck M, Masur K, Barth T, Müller-Enoch D, Wirth T, and Haehner T
- Subjects
- Animals, Cytochrome P-450 CYP2E1 metabolism, Dodecanol, Humans, Mice, Mice, Nude, Oxidative Stress, Carcinoma, Hepatocellular drug therapy, Liver Neoplasms drug therapy
- Abstract
Cytochrome P450 2E1 (CYP2E1) is a key target protein in the development of alcoholic and nonalcoholic fatty liver disease (FLD). The pathophysiological correlate is the massive production of reactive oxygen species. The role of CYP2E1 in the development of hepatocellular carcinoma (HCC), the final complication of FLD, remains controversial. Specifically, CYP2E1 has not yet been defined as a molecular target for HCC therapy. In addition, a CYP2E1-specific drug has not been developed. We have already shown that our newly developed CYP2E1 inhibitor 12-imidazolyl-1-dodecanol (I-ol) was therapeutically effective against alcoholic and nonalcoholic steatohepatitis. In this study, we investigated the effect of I-ol on HCC tumorigenesis and whether I-ol could serve as a possible treatment option for terminal-stage FLD. I-ol exerted a very highly significant antitumour effect against hepatocellular HepG2 cells. Cell viability was reduced in a dose-dependent manner, with only the highest doses causing a cytotoxic effect associated with caspase 3/7 activation. Comparable results were obtained for the model colorectal adenocarcinoma cell line, DLD-1, whose tumorigenesis is also associated with CYP2E1. Transcriptome analyses showed a clear effect of I-ol on apoptosis and cell-cycle regulation, with the increased expression of p27Kip1 being particularly noticeable. These observations were confirmed at the protein level for HepG2 and DLD-1 cells grafted on a chorioallantoic membrane. Cell-cycle analysis showed a complete loss of proliferating cells with a simultaneous increase in S-phase arrest beginning at a threshold dose of 30 μ M. I-ol also reduced xenograft tumour growth in nude mice. This antitumour effect was not associated with tumour cachexia. I-ol was not toxic to healthy tissues or organs. This study demonstrates for the first time the therapeutic effect of the specific CYP2E1 inhibitor I-ol on the tumorigenesis of HCC. Our findings imply that I-ol can potentially be applied therapeutically on patients at the final stage of FLD., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2021 Torsten Diesinger et al.)
- Published
- 2021
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14. Baseline MAPK signaling activity confers intrinsic radioresistance to KRAS-mutant colorectal carcinoma cells by rapid upregulation of heterogeneous nuclear ribonucleoprotein K (hnRNP K).
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Eder S, Arndt A, Lamkowski A, Daskalaki W, Rump A, Priller M, Genze F, Wardelmann E, Port M, and Steinestel K
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- Aged, Aged, 80 and over, Animals, Apoptosis radiation effects, Cell Cycle radiation effects, Cell Line, Tumor, Chick Embryo, Chorioallantoic Membrane blood supply, Colorectal Neoplasms enzymology, Colorectal Neoplasms genetics, Colorectal Neoplasms pathology, Dose-Response Relationship, Radiation, Female, Gene Expression Regulation, Neoplastic, Genetic Predisposition to Disease, Heterogeneous-Nuclear Ribonucleoprotein K, Humans, MAP Kinase Kinase Kinases antagonists & inhibitors, Male, Middle Aged, Phenotype, Protein Kinase Inhibitors pharmacology, RNA Interference, Radiation Tolerance drug effects, Ribonucleoproteins genetics, Signal Transduction drug effects, Time Factors, Transfection, Up-Regulation, Biomarkers, Tumor genetics, Colorectal Neoplasms radiotherapy, MAP Kinase Kinase Kinases metabolism, Mutation, Proto-Oncogene Proteins p21(ras) genetics, Radiation Tolerance genetics, Ribonucleoproteins metabolism, Signal Transduction radiation effects
- Abstract
Heterogeneous nuclear ribonucleoprotein K (hnRNP K) is overexpressed in malignant tumors and involved in DNA damage response upon ionizing radiation (IR). Here, we investigate its role in radioresistance of colorectal carcinoma (CRC) and evaluate a pharmacological approach to enhance CRC radiosensitivity via downregulation of hnRNP K. We show that hnRNP K is overexpressed in CRC tissue specimens and upregulated in response to IR in vitro, which occurs faster in KRAS-mutant CRC cells. HnRNP K knockdown impairs cell survival, cell cycle progression and KRAS-dependent radioresistance and increases apoptosis. Using the chicken chorioallantoic membrane assay, a decrease in xenograft tumor growth and radioresistance upon hnRNP K depletion could be verified in vivo, and comparable effects were achieved by suppression of hnRNP K expression using the MEK inhibitor MEK162 (Binimetinib). In summary, KRAS-mutant CRC shows intrinsic radioresistance along with rapid upregulation of hnRNP K in response to IR that can effectively be targeted by MEK inhibition. Our results point towards a possible use of MAPK pathway inhibitors to decrease radioresistance of KRAS-mutant CRC via downregulation of hnRNP K., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)
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- 2017
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15. Tbx3 fosters pancreatic cancer growth by increased angiogenesis and activin/nodal-dependent induction of stemness.
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Perkhofer L, Walter K, Costa IG, Carrasco MC, Eiseler T, Hafner S, Genze F, Zenke M, Bergmann W, Illing A, Hohwieler M, Köhntop R, Lin Q, Holzmann KH, Seufferlein T, Wagner M, Liebau S, Hermann PC, Kleger A, and Müller M
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- AC133 Antigen metabolism, Adult, Aged, Aged, 80 and over, Apoptosis, Cell Movement, Cell Proliferation, Female, Humans, Male, Microscopy, Fluorescence, Middle Aged, Neoplastic Stem Cells metabolism, Neovascularization, Pathologic, Pancreatic Neoplasms metabolism, Phenotype, Spheroids, Cellular cytology, Spheroids, Cellular metabolism, T-Box Domain Proteins genetics, Activins metabolism, Neoplastic Stem Cells cytology, Nodal Protein metabolism, Pancreatic Neoplasms pathology, T-Box Domain Proteins metabolism
- Abstract
Cell fate decisions and pluripotency, but also malignancy depend on networks of key transcriptional regulators. The T-box transcription factor TBX3 has been implicated in the regulation of embryonic stem cell self-renewal and cardiogenesis. We have recently discovered that forced TBX3 expression in embryonic stem cells promotes mesendoderm specification directly by activating key lineage specification factors and indirectly by enhancing paracrine NODAL signalling. Interestingly, aberrant TBX3 expression is associated with breast cancer and melanoma formation. In other cancers, loss of TBX3 expression is associated with a more aggressive phenotype e.g. in gastric and cervical cancer. The precise function of TBX3 in pancreatic ductal adenocarcinoma remains to be determined. In the current study we provide conclusive evidence for TBX3 overexpression in pancreatic cancer samples as compared to healthy tissue. While proliferation remains unaltered, forced TBX3 expression strongly increases migration and invasion, but also angiogenesis in vitro and in vivo. Finally, we describe the TBX3-dependency of cancer stem cells that perpetuate themselves through an autocrine TBX3-ACTIVIN/NODAL signalling loop to sustain stemness. Thus, TBX3 is a new key player among pluripotency-related genes driving cancer formation., (Copyright © 2016 Helmholtz Zentrum München. Published by Elsevier B.V. All rights reserved.)
- Published
- 2016
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16. The small conductance calcium-activated potassium channel 3 (SK3) is a molecular target for Edelfosine to reduce the invasive potential of urothelial carcinoma cells.
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Steinestel K, Eder S, Ehinger K, Schneider J, Genze F, Winkler E, Wardelmann E, Schrader AJ, and Steinestel J
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- Adult, Aged, Calcium metabolism, Carcinoma genetics, Carcinoma pathology, Cell Movement drug effects, Female, Gene Expression Regulation, Neoplastic drug effects, Humans, Male, Middle Aged, Neoplasm Invasiveness genetics, Small-Conductance Calcium-Activated Potassium Channels genetics, Urinary Bladder Neoplasms genetics, Urinary Bladder Neoplasms pathology, Urothelium drug effects, Urothelium pathology, Carcinoma drug therapy, Phospholipid Ethers administration & dosage, Small-Conductance Calcium-Activated Potassium Channels biosynthesis, Urinary Bladder Neoplasms drug therapy
- Abstract
Metastasis is the survival-determining factor in urothelial carcinoma (UC) of the urinary bladder. The small conductance calcium-activated potassium channel 3 (SK3) enhances tumor cell invasion in breast cancer and malignant melanoma. Since Edelfosine, a glycerophospholipid with antitumoral properties, effectively inhibits SK3 channel activity, our goal was to evaluate SK3 as a potential molecular target to inhibit the gain of an invasive phenotype in UC. SK3 protein expression was analyzed in 208 tissue samples and UC cell lines. Effects of Edelfosine on SK3 expression and intracellular calcium levels as well as on cell morphology, cell survival and proliferation were assessed using immunoblotting, potentiometric fluorescence microscopy, and clonogenic/cell survival assay; furthermore, we analyzed the effect of Edelfosine and SK3 RNAi knockdown on tumor cell migration and invasion in vitro and in vivo. We found that SK3 is strongly expressed in muscle-invasive UC and in the RT112 cellular tumor model. Higher concentrations of Edelfosine have a strong antitumoral effect on UC cells, while 1 μM effectively inhibits migration/invasion of UC cells in vitro and in vivo comparable to the SK3 knockdown phenotype. Taken together, our results show strong expression of SK3 in muscle-invasive UC, consistent with the postulated role of the protein in tumor cell invasion. Edelfosine is able to effectively inhibit migration and invasion of UC cells in vitro and in vivo in an SK3-dependent way, pointing towards a possible role for Edelfosine as an antiinvasive drug to effectively inhibit UC cell invasion and metastasis.
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- 2016
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17. Erratum to: The small conductance calcium-activated potassium channel 3 (SK3) is a molecular target for Edelfosine to reduce the invasive potential of urothelial carcinoma cells.
- Author
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Steinestel K, Eder S, Ehinger K, Schneider J, Genze F, Winkler E, Wardelmann E, Schrader AJ, and Steinestel J
- Published
- 2016
- Full Text
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18. PKM2 promotes tumor angiogenesis by regulating HIF-1α through NF-κB activation.
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Azoitei N, Becher A, Steinestel K, Rouhi A, Diepold K, Genze F, Simmet T, and Seufferlein T
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- Adult, Aged, Aged, 80 and over, Animals, Apoptosis, Cell Hypoxia, Cell Line, Tumor, Cell Nucleus metabolism, Cell Proliferation, Cell Survival, Chickens, Female, Gene Knockdown Techniques, Humans, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Male, Middle Aged, Models, Biological, Neovascularization, Pathologic genetics, Pancreatic Neoplasms genetics, Protein Binding, Protein Transport, Signal Transduction genetics, Transcription Factor RelA metabolism, Transcription, Genetic, Vascular Endothelial Growth Factor A metabolism, Thyroid Hormone-Binding Proteins, Carrier Proteins metabolism, Hypoxia-Inducible Factor 1, alpha Subunit genetics, Membrane Proteins metabolism, NF-kappa B metabolism, Neovascularization, Pathologic pathology, Pancreatic Neoplasms blood supply, Pancreatic Neoplasms metabolism, Thyroid Hormones metabolism
- Abstract
Background: Initially identified as a molecule that regulates the final step of glycolysis, the M2 isoform of pyruvate kinase (PKM2) was recently reported to have a central role in the metabolic reprogramming of cancer cells as well as participating in cell cycle progression and gene transcription. Despite intensive efforts, the intricate molecular mechanisms through which PKM2 regulates tumor progression remain elusive., Methods: The proliferation and apoptosis of various pancreatic cancer cells using lentiviral-mediated PKM2 abrogation were assessed in vitro via Western blot and flow cytometric assay while the in vivo experiments involved tumor xenograft on chicken chorionallantoic membranes and immunohistochemistry on human tissue specimens. In order to decipher the molecular mechanism of HIF-1α and p65/RelA regulation by PKM2 in cancer cells cultivated in hypoxic atmosphere or normoxia we involved various biochemical assays such as Western blotting, immunoprecipitation, reporter gene assay and ELISA., Results: Strong expression of PKM2 was observed in 68 % of human pancreatic adenocarcinoma specimens and almost all analyzed pancreatic cancer cell lines. Abrogation of PKM2 resulted in impaired proliferation and augmented apoptosis in vitro as well as impaired tumor growth and decreased blood vessel formation in vivo. Furthermore, deletion of PKM2 negatively impacted hypoxia-induced HIF-1α accumulation and promoter activity ultimately resulting in impaired secretion of VEGF., Conclusions: Our study suggests that in hypoxic pancreatic tumors PKM2 interferes both with NF-κB/p65 and HIF-1α activation that ultimately triggers VEGF-A secretion and subsequent blood vessel formation.
- Published
- 2016
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19. A time frame permissive for Protein Kinase D2 activity to direct angiogenesis in mouse embryonic stem cells.
- Author
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Müller M, Schröer J, Azoitei N, Eiseler T, Bergmann W, Köhntop R, Lin Q, Costa IG, Zenke M, Genze F, Weidgang C, Seufferlein T, Liebau S, and Kleger A
- Subjects
- Animals, Cell Differentiation drug effects, Cell Line, Chickens, Chorioallantoic Membrane blood supply, Doxycycline pharmacology, Embryoid Bodies cytology, Embryoid Bodies transplantation, Gene Knock-In Techniques, Immunohistochemistry, Induced Pluripotent Stem Cells cytology, Induced Pluripotent Stem Cells metabolism, Mice, Mice, Inbred C57BL, Mouse Embryonic Stem Cells cytology, Neovascularization, Pathologic, Protein Kinase C genetics, Protein Kinase C metabolism, Protein Kinase D2, Protein Kinases genetics, Real-Time Polymerase Chain Reaction, Mouse Embryonic Stem Cells metabolism, Protein Kinases metabolism
- Abstract
The protein kinase D isoenzymes PKD1/2/3 are prominent downstream targets of PKCs (Protein Kinase Cs) and phospholipase D in various biological systems. Recently, we identified PKD isoforms as novel mediators of tumour cell-endothelial cell communication, tumour cell motility and metastasis. Although PKD isoforms have been implicated in physiological/tumour angiogenesis, a role of PKDs during embryonic development, vasculogenesis and angiogenesis still remains elusive. We investigated the role of PKDs in germ layer segregation and subsequent vasculogenesis and angiogenesis using mouse embryonic stem cells (ESCs). We show that mouse ESCs predominantly express PKD2 followed by PKD3 while PKD1 displays negligible levels. Furthermore, we demonstrate that PKD2 is specifically phosphorylated/activated at the time of germ layer segregation. Time-restricted PKD2-activation limits mesendoderm formation and subsequent cardiovasculogenesis during early differentiation while leading to branching angiogenesis during late differentiation. In line, PKD2 loss-of-function analyses showed induction of mesendodermal differentiation in expense of the neuroectodermal germ layer. Our in vivo findings demonstrate that embryoid bodies transplanted on chicken chorioallantoic membrane induced an angiogenic response indicating that timed overexpression of PKD2 from day 4 onwards leads to augmented angiogenesis in differentiating ESCs. Taken together, our results describe novel and time-dependent facets of PKD2 during early cell fate determination.
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- 2015
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20. High-resolution MRI analysis of breast cancer xenograft on the chick chorioallantoic membrane.
- Author
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Zuo Z, Syrovets T, Genze F, Abaei A, Ma G, Simmet T, and Rasche V
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- Animals, Cell Line, Tumor, Chick Embryo, Chorioallantoic Membrane, Contrast Media, Diffusion Magnetic Resonance Imaging methods, Egg White, Egg Yolk, Feasibility Studies, Female, Gadolinium, Heterografts, Humans, Image Processing, Computer-Assisted methods, Organometallic Compounds, Reproducibility of Results, Temperature, Tumor Burden, Breast Neoplasms pathology, Magnetic Resonance Imaging methods
- Abstract
The chick chorioallantoic membrane (CAM) model has been successfully used to study angiogenesis, cancer progression and its pharmacological treatment, tumor pharmacokinetics, and properties of novel nanomaterials. MRI is an attractive technique for non-invasive and longitudinal monitoring of physiological processes and tumor growth. This study proposes an age-adapted cooling regime for immobilization of the chick embryo, enabling high-resolution MRI of the embryo and the CAM tumor xenograft. 64 chick embryos were enrolled in this study. The novel immobilization and imaging protocol was optimized in 29 embryos. From d7 to d18 immobilization of the embryo up to 90 min was achieved by cooling at 4 °C pre-imaging, with cooling times adapted to age. Its application to tumor growth monitoring was evaluated in 15 embryos after xenotransplantation of human MDA-MB-231 breast cancer cells on CAM. Tumor volumes were monitored from d4 to d9 after grafting (d11 to d16 after incubation) applying a T2 -weighted multislice RARE sequence. At d9 after grafting, the tumors were collected and compared with the MRI-derived data by histology and weight measurements. Additional imaging methods comprising DWI, T2 mapping, and the bio-distribution of contrast agents were tested at d9 after grafting in 20 further embryos. With the adaptive cooling regime, motion artifacts could be completely avoided for up to 90 min scan time, enabling high-resolution in ovo imaging. Excellent anatomical details could be obtained in the embryo and tumors. Tumor volumes could be quantified over time. The results prove the feasibility of high-resolution MRI for longitudinal tumor and organ growth monitoring. The suggested method is promising for future applications such as testing tailored and/or targeted treatment strategies, longitudinal monitoring of tumor development, analysis of therapeutic efficacies of drugs, or assessment of tumor pharmacokinetics. The method provides an alternative to animal experimentation., (Copyright © 2015 John Wiley & Sons, Ltd.)
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- 2015
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21. HSP90 supports tumor growth and angiogenesis through PRKD2 protein stabilization.
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Azoitei N, Diepold K, Brunner C, Rouhi A, Genze F, Becher A, Kestler H, van Lint J, Chiosis G, Koren J 3rd, Fröhling S, Scholl C, and Seufferlein T
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- Animals, Apoptosis physiology, Cell Hypoxia physiology, Cell Line, Tumor, Female, HCT116 Cells, Humans, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Mice, Mice, Nude, NF-kappa B metabolism, Proteasome Endopeptidase Complex metabolism, Signal Transduction physiology, Vascular Endothelial Growth Factor A metabolism, HSP90 Heat-Shock Proteins metabolism, Neovascularization, Pathologic metabolism, Protein Kinase C metabolism
- Abstract
The kinase PRKD2 (protein kinase D) is a crucial regulator of tumor cell-endothelial cell communication in gastrointestinal tumors and glioblastomas, but its mechanistic contributions to malignant development are not understood. Here, we report that the oncogenic chaperone HSP90 binds to and stabilizes PRKD2 in human cancer cells. Pharmacologic inhibition of HSP90 with structurally divergent small molecules currently in clinical development triggered proteasome-dependent degradation of PRKD2, augmenting apoptosis in human cancer cells of various tissue origins. Conversely, ectopic expression of PRKD2 protected cancer cells from the apoptotic effects of HSP90 abrogation, restoring blood vessel formation in two preclinical models of solid tumors. Mechanistic studies revealed that PRKD2 is essential for hypoxia-induced accumulation of hypoxia-inducible factor-1α (HIF1α) and activation of NF-κB in tumor cells. Notably, ectopic expression of PRKD2 was able to partially restore HIF1α and secreted VEGF-A levels in hypoxic cancer cells treated with HSP90 inhibitors. Taken together, our findings indicate that signals from hypoxia and HSP90 pathways are interconnected and funneled by PRKD2 into the NF-κB/VEGF-A signaling axis to promote tumor angiogenesis and tumor growth., (©2014 American Association for Cancer Research.)
- Published
- 2014
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22. Stilbene induced inhibition of androgen receptor dimerization: implications for AR and ARΔLBD-signalling in human prostate cancer cells.
- Author
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Streicher W, Luedeke M, Azoitei A, Zengerling F, Herweg A, Genze F, Schrader MG, Schrader AJ, and Cronauer MV
- Subjects
- Cell Line, Tumor, Dimerization, Humans, Male, Prostatic Neoplasms pathology, Receptors, Androgen chemistry, Receptors, Androgen metabolism, Signal Transduction, Prostatic Neoplasms metabolism, Receptors, Androgen drug effects, Stilbenes pharmacology
- Abstract
Background: Advanced castration resistant prostate cancer (CRPC) is often characterized by an increase of C-terminally truncated, constitutively active androgen receptor (AR) variants. Due to the absence of a ligand binding domain located in the AR-C-terminus, these receptor variants (also termed ARΔLBD) are unable to respond to all classical forms of endocrine treatments like surgical/chemical castration and/or application of anti-androgens., Methodology: In this study we tested the effects of the naturally occurring stilbene resveratrol (RSV) and (E)-4-(2, 6-Difluorostyryl)-N, N-dimethylaniline, a fluorinated dialkylaminostilbene (FIDAS) on AR- and ARΔLBD in prostate cancer cells. The ability of the compounds to modulate transcriptional activity of AR and the ARΔLBD-variant Q640X was shown by reporter gene assays. Expression of endogenous AR and ARΔLBD mRNA and protein levels were determined by qRT-PCR and Western Blot. Nuclear translocation of AR-molecules was analyzed by fluorescence microscopy. AR and ARΔLBD/Q640X homo-/heterodimer formation was assessed by mammalian two hybrid assays. Biological activity of both compounds in vivo was demonstrated using a chick chorioallantoic membrane xenograft assay., Results: The stilbenes RSV and FIDAS were able to significantly diminish AR and Q640X-signalling. Successful inhibition of the Q640X suggests that RSV and FIDAS are not interfering with the AR-ligand binding domain like all currently available anti-hormonal drugs. Repression of AR and Q640X-signalling by RSV and FIDAS in prostate cancer cells was caused by an inhibition of the AR and/or Q640X-dimerization. Although systemic bioavailability of both stilbenes is very low, both compounds were also able to downregulate tumor growth and AR-signalling in vivo., Conclusion: RSV and FIDAS are able to inhibit the dimerization of AR and ARΔLBD molecules suggesting that stilbenes might serve as lead compounds for a novel generation of AR-inhibitors.
- Published
- 2014
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23. Active targeting of mesoporous silica drug carriers enhances γ-secretase inhibitor efficacy in an in vivo model for breast cancer.
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Wittig R, Rosenholm JM, von Haartman E, Hemming J, Genze F, Bergman L, Simmet T, Lindén M, and Sahlgren C
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- Animals, Enzyme Inhibitors chemistry, Female, Humans, Mice, Mice, Nude, Porosity, Triazines chemistry, Amyloid Precursor Protein Secretases antagonists & inhibitors, Breast Neoplasms drug therapy, Drug Carriers chemistry, Enzyme Inhibitors therapeutic use, Nanoparticles chemistry, Silicon Dioxide chemistry, Triazines therapeutic use
- Abstract
Aim: In this article, we use an alternative cancer model for the evaluation of nanotherapy, and assess the impact of surface functionalization and active targeting of mesoporous silica nanoparticles (MSNPs) on therapeutic efficacy in vivo., Materials & Methods: We used the chorioallantoic membrane xenograft assay to investigate the biodistribution and therapeutic efficacy of folate versus polyethyleneimine-functionalized γ-secretase inhibitor-loaded MSNPs in breast and prostate tumor models., Results: γ-secretase inhibitor-loaded MSNPs inhibited tumor growth in breast and prostate cancer xenografts. Folate conjugation improved the therapeutic outcome in folic acid receptor-positive breast cancer, but not in prostate cancer lacking the receptor., Conclusion: The results demonstrate that therapeutic efficacy is linked to cellular uptake of MSNPs as opposed to tumor accumulation, and show that MSNP-based delivery of γ-secretase inhibitors is therapeutically effective in both breast and prostate cancer. In this article, we present a model system for a medium-to-high throughput, cost-effective, quantitative evaluation of nanoparticulate drug carriers.
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- 2014
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24. Thioredoxin-1 promotes anti-inflammatory macrophages of the M2 phenotype and antagonizes atherosclerosis.
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El Hadri K, Mahmood DF, Couchie D, Jguirim-Souissi I, Genze F, Diderot V, Syrovets T, Lunov O, Simmet T, and Rouis M
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- Animals, Aortic Diseases chemically induced, Aortic Diseases genetics, Aortic Diseases immunology, Aortic Diseases metabolism, Aortic Diseases pathology, Apolipoprotein E2 genetics, Apolipoprotein E2 metabolism, Atherosclerosis chemically induced, Atherosclerosis genetics, Atherosclerosis immunology, Atherosclerosis metabolism, Atherosclerosis pathology, Biomarkers metabolism, Cyclin-Dependent Kinase Inhibitor p16 metabolism, Cytokines metabolism, DNA-(Apurinic or Apyrimidinic Site) Lyase metabolism, Disease Models, Animal, Humans, Inflammation Mediators metabolism, Lectins, C-Type metabolism, Lipopolysaccharides, Macrophages, Peritoneal immunology, Macrophages, Peritoneal metabolism, Macrophages, Peritoneal pathology, Mannose Receptor, Mannose-Binding Lectins metabolism, Mice, Mice, Inbred C57BL, Mice, Knockout, Mice, Transgenic, Phenotype, Receptors, Cell Surface metabolism, Recombinant Proteins pharmacology, Time Factors, Transcription Factor AP-1 metabolism, Anti-Inflammatory Agents pharmacology, Aortic Diseases prevention & control, Atherosclerosis prevention & control, Cell Differentiation drug effects, Macrophages, Peritoneal drug effects, Thioredoxins pharmacology
- Abstract
Objective: Oxidative stress is believed to play a key role in cardiovascular disorders. Thioredoxin (Trx) is an oxidative stress-limiting protein with anti-inflammatory and antiapoptotic properties. Here, we analyzed whether Trx-1 might exert atheroprotective effects by promoting macrophage differentiation into the M2 anti-inflammatory phenotype., Methods and Results: Trx-1 at 1 μg/mL induced downregulation of p16(INK4a) and significantly promoted the polarization of anti-inflammatory M2 macrophages in macrophages exposed to interleukin (IL)-4 at 15 ng/mL or IL-4/IL-13 (10 ng/mL each) in vitro, as evidenced by the expression of the CD206 and IL-10 markers. In addition, Trx-1 induced downregulation of nuclear translocation of activator protein-1 and Ref-1, and significantly reduced the lipopolysaccharide-induced differentiation of inflammatory M1 macrophages, as indicated by the decreased expression of the M1 cytokines, tumor necrosis factor-α and monocyte chemoattractant protein-1. Consistently, Trx-1 administered to hyperlipoproteinemic ApoE2.Ki mice at 30 μg/30 g body weight challenged either with lipopolysaccharide at 30 μg/30 g body weight or with IL-4 at 500 ng/30 g body weight significantly induced the M2 phenotype while inhibiting differentiation of macrophages into the M1 phenotype in liver and thymus. ApoE2.Ki mice challenged once weekly with lipopolysaccharide for 5 weeks developed severe atherosclerotic lesions enriched with macrophages expressing predominantly M1 over M2 markers. In contrast, however, daily injections of Trx-1 shifted the phenotype pattern of lesional macrophages in these animals to predominantly M2 over M1, and the aortic lesion area was significantly reduced (from 100%±18% to 62.8%±9.8%; n=8; P<0.01). Consistently, Trx-1 colocalized with M2 but not with M1 macrophage markers in human atherosclerotic vessel specimens., Conclusions: The ability of Trx-1 to promote differentiation of macrophages into an alternative, anti-inflammatory phenotype may explain its protective effects in cardiovascular diseases. These data provide novel insight into the link between oxidative stress and cardiovascular diseases.
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- 2012
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25. Targeting of KRAS mutant tumors by HSP90 inhibitors involves degradation of STK33.
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Azoitei N, Hoffmann CM, Ellegast JM, Ball CR, Obermayer K, Gößele U, Koch B, Faber K, Genze F, Schrader M, Kestler HA, Döhner H, Chiosis G, Glimm H, Fröhling S, and Scholl C
- Subjects
- Apoptosis, Cell Line, Tumor, Colonic Neoplasms drug therapy, Colonic Neoplasms pathology, Humans, Proteasome Endopeptidase Complex physiology, Proto-Oncogene Proteins physiology, Proto-Oncogene Proteins p21(ras), Ubiquitination, ras Proteins physiology, HSP90 Heat-Shock Proteins antagonists & inhibitors, Mutation, Protein Serine-Threonine Kinases metabolism, Proto-Oncogene Proteins genetics, ras Proteins genetics
- Abstract
Previous efforts to develop drugs that directly inhibit the activity of mutant KRAS, the most commonly mutated human oncogene, have not been successful. Cancer cells driven by mutant KRAS require expression of the serine/threonine kinase STK33 for their viability and proliferation, identifying STK33 as a context-dependent therapeutic target. However, specific strategies for interfering with the critical functions of STK33 are not yet available. Here, using a mass spectrometry-based screen for STK33 protein interaction partners, we report that the HSP90/CDC37 chaperone complex binds to and stabilizes STK33 in human cancer cells. Pharmacologic inhibition of HSP90, using structurally divergent small molecules currently in clinical development, induced proteasome-mediated degradation of STK33 in human cancer cells of various tissue origin in vitro and in vivo, and triggered apoptosis preferentially in KRAS mutant cells in an STK33-dependent manner. Furthermore, HSP90 inhibitor treatment impaired sphere formation and viability of primary human colon tumor-initiating cells harboring mutant KRAS. These findings provide mechanistic insight into the activity of HSP90 inhibitors in KRAS mutant cancer cells, indicate that the enhanced requirement for STK33 can be exploited to target mutant KRAS-driven tumors, and identify STK33 depletion through HSP90 inhibition as a biomarker-guided therapeutic strategy with immediate translational potential.
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- 2012
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26. Comparison of in vitro- and chorioallantoic membrane (CAM)-culture systems for cryopreserved medulla-contained human ovarian tissue.
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Isachenko V, Mallmann P, Petrunkina AM, Rahimi G, Nawroth F, Hancke K, Felberbaum R, Genze F, Damjanoski I, and Isachenko E
- Subjects
- Adolescent, Adult, Animals, Chick Embryo, Desmin analysis, Female, Humans, Immunohistochemistry, Mice, Mice, SCID, Neovascularization, Physiologic, Ovarian Follicle growth & development, Ovarian Follicle metabolism, Ovarian Follicle transplantation, Ovary blood supply, Ovary transplantation, Reproducibility of Results, Time Factors, Transplantation, Heterologous, Young Adult, von Willebrand Factor analysis, Chorioallantoic Membrane physiology, Cryopreservation methods, Ovary physiology, Tissue Culture Techniques methods
- Abstract
At present, there are three ways to determine effectively the quality of the cryopreservation procedure using ovarian tissue before the re-implantation treatment: evaluation of follicles after post-thawing xenotransplantation to SCID mouse, in-vitro culture in a large volume of culture medium under constant agitation and culture on embryonic chorio-allantoic membrane within a hen's eggs. The aim of this study was to compare the two methods, culture in vitro and culture on embryonic chorioallantoic membrane (CAM) of cryopreserved human ovarian medulla-contained and medulla-free cortex. Ovarian fragments were divided into small pieces (1.5-2.0×1.0-1.2×0.8-1.5) of two types, cortex with medulla and medulla-free cortex, frozen, thawed and randomly divided into the following four groups. Group 1: medulla-free cortex cultured in vitro for 8 days in large volume of medium with mechanical agitation, Group 2: medulla-containing cortex cultured in vitro, Group 3: medulla-free cortex cultured in CAM-system for 5 days, Group 4: medulla-containing cortex cultured in CAM-system. The efficacy of the tissue culture was evaluated by the development of follicles and by intensiveness of angiogenesis in the tissue (von Willebrand factor and Desmin). For Group 1, 2, 3 and 4, respectively 85%, 85%, 87% and 84% of the follicles were morphologically normal (P>0.1). The immunohistochemical analysis showed that angiogenesis detected by von Willebrand factor was lower in groups 1 and 3 (medulla-free cortex). Neo-vascularisation (by Desmin) was observed only in ovarian tissue of Group 4 (medulla-contained cortex after CAM-culture). It appears that the presence of medulla in ovarian pieces is beneficial for post-thaw development of cryopreserved human ovarian tissue. For medical practice it is recommended for evaluation of post-warming ovarian tissue to use the CAM-system as a valuable alternative to xenotransplantation and for cryopreservation of these tissues to prepare ovarian medulla-contained strips.
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- 2012
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27. Protein kinase D2 is a novel regulator of glioblastoma growth and tumor formation.
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Azoitei N, Kleger A, Schoo N, Thal DR, Brunner C, Pusapati GV, Filatova A, Genze F, Möller P, Acker T, Kuefer R, Van Lint J, Baust H, Adler G, and Seufferlein T
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- Animals, Apoptosis, Blotting, Western, Brain Neoplasms enzymology, Cell Cycle, Cell Proliferation, Chickens, Chorioallantoic Membrane metabolism, Cyclin D1 metabolism, Glioblastoma enzymology, Humans, Immunoenzyme Techniques, RNA, Small Interfering genetics, TRPP Cation Channels antagonists & inhibitors, TRPP Cation Channels genetics, Brain enzymology, Brain Neoplasms pathology, Glioblastoma pathology, TRPP Cation Channels metabolism
- Abstract
Glioblastoma multiforme, a highly aggressive tumor of the central nervous system, has a dismal prognosis that is due in part to its resistance to radio- and chemotherapy. The protein kinase C (PKC) family of serine threonine kinases has been implicated in the formation and proliferation of glioblastoma multiforme. Members of the protein kinase D (PKD) family, which consists of PKD1, -2 and, -3, are prominent downstream targets of PKCs and could play a major role in glioblastoma growth. PKD2 was highly expressed in both low-grade and high-grade human gliomas. The number of PKD2-positive tumor cells increased with glioma grading (P < .001). PKD2 was also expressed in CD133-positive glioblastoma stem cells and various glioblastoma cell lines in which the kinase was found to be constitutively active. Inhibition of PKDs by pharmacological inhibitors resulted in substantial inhibition of glioblastoma proliferation. Furthermore, specific depletion of PKD2 by siRNA resulted in a marked inhibition of anchorage-dependent and -independent proliferation and an accumulation of glioblastoma cells in G0/G1, accompanied by a down-regulation of cyclin D1 expression. In addition, PKD2-depleted glioblastoma cells exhibited substantially reduced tumor formation in vivo on chicken chorioallantoic membranes. These findings identify PKD2 as a novel mediator of glioblastoma cell growth in vitro and in vivo and thereby as a potential therapeutic target for this devastating disease.
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- 2011
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28. Inhibition of glycogen synthase kinase-3β counteracts ligand-independent activity of the androgen receptor in castration resistant prostate cancer.
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Schütz SV, Schrader AJ, Zengerling F, Genze F, Cronauer MV, and Schrader M
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- Active Transport, Cell Nucleus drug effects, Cell Line, Tumor, Cell Nucleus drug effects, Cell Nucleus metabolism, Cell Proliferation drug effects, Enzyme Activation drug effects, Gene Silencing, Glycogen Synthase Kinase 3 chemistry, Glycogen Synthase Kinase 3 genetics, Glycogen Synthase Kinase 3 metabolism, Glycogen Synthase Kinase 3 beta, Humans, Indoles pharmacology, Karyopherins metabolism, Ligands, Male, Maleimides pharmacology, Phosphorylation drug effects, Prostatic Neoplasms genetics, Prostatic Neoplasms metabolism, Receptors, Cytoplasmic and Nuclear metabolism, Signal Transduction drug effects, Tyrosine metabolism, Up-Regulation drug effects, Exportin 1 Protein, Glycogen Synthase Kinase 3 antagonists & inhibitors, Orchiectomy, Prostatic Neoplasms pathology, Prostatic Neoplasms surgery, Protein Kinase Inhibitors pharmacology, Receptors, Androgen metabolism
- Abstract
In order to generate genomic signals, the androgen receptor (AR) has to be transported into the nucleus upon androgenic stimuli. However, there is evidence from in vitro experiments that in castration-resistant prostate cancer (CRPC) cells the AR is able to translocate into the nucleus in a ligand-independent manner. The recent finding that inhibition of the glycogen-synthase-kinase 3β (GSK-3β) induces a rapid nuclear export of the AR in androgen-stimulated prostate cancer cells prompted us to analyze the effects of a GSK-3β inhibition in the castration-resistant LNCaP sublines C4-2 and LNCaP-SSR. Both cell lines exhibit high levels of nuclear AR in the absence of androgenic stimuli. Exposure of these cells to the maleimide SB216763, a potent GSK-3β inhibitor, resulted in a rapid nuclear export of the AR even under androgen-deprived conditions. Moreover, the ability of C4-2 and LNCaP-SSR cells to grow in the absence of androgens was diminished after pharmacological inhibition of GSK-3β in vitro. The ability of SB216763 to modulate AR signalling and function in CRPC in vivo was additionally demonstrated in a modified chick chorioallantoic membrane xenograft assay after systemic delivery of SB216763. Our data suggest that inhibition of GSK-3β helps target the AR for export from the nucleus thereby diminishing the effects of mislocated AR in CRPC cells. Therefore, inhibition of GSK-3β could be an interesting new strategy for the treatment of CRPC.
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- 2011
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29. Protein kinase D2 is a crucial regulator of tumour cell-endothelial cell communication in gastrointestinal tumours.
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Azoitei N, Pusapati GV, Kleger A, Möller P, Küfer R, Genze F, Wagner M, van Lint J, Carmeliet P, Adler G, and Seufferlein T
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- Animals, Cell Communication physiology, Chick Embryo, Chorioallantoic Membrane blood supply, Chorioallantoic Membrane enzymology, Coculture Techniques, Endothelial Cells pathology, Endothelium, Vascular enzymology, Gastrointestinal Neoplasms blood supply, Gastrointestinal Neoplasms enzymology, Gene Knockdown Techniques, Humans, Mice, Mice, Nude, Neoplasm Transplantation, Neovascularization, Pathologic enzymology, Neovascularization, Pathologic pathology, Pancreatic Neoplasms blood supply, Pancreatic Neoplasms enzymology, Pancreatic Neoplasms pathology, Protein Kinase D2, Protein Kinases genetics, Protein Kinases metabolism, Transplantation, Heterologous, Tumor Cells, Cultured, Vascular Endothelial Growth Factor A physiology, Gastrointestinal Neoplasms pathology, Protein Kinases physiology
- Abstract
Background: Tumour angiogenesis is crucially dependent on the communication between the tumour and the associated endothelium. Protein kinase D (PKD) isoenzymes mediate vascular endothelial growth factor-A (VEGF-A) induced endothelial cell proliferation and migration and are also highly expressed in various tumours., Aim: To examine the role of PKDs for tumour proliferation and angiogenesis selectively in pancreatic and gastric tumours and in tumour-associated endothelium in vitro and in vivo., Methods: PKD2 expression in human tumours was determined by immunohistochemistry. The effect of PKD2 depletion in endothelial cells by siRNAs was examined in sprouting assays, the chorioallantois model (CAM) and tumour xenografts. In murine endothelium in vivo PKD2 was knocked-down by splice switching oligonucleotides. Human PKD2 was depleted in xenografts by siRNAs and PKD2-miRs. PKD2 activation by hypoxia and its role for hypoxia-induced NR4/TR3- and VEGF-A promoter activity, expression and secretion was investigated in cell lines., Results: PKD2 is expressed in gastrointestinal tumours and in the tumour-associated endothelium. Tumour growth and angiogenesis in the CAM and in tumour xenografts require PKD expression in endothelial cells. Conversely, hypoxia activates PKD2 in pancreatic cancer cells and PKD2 was identified as the major mediator of hypoxia-stimulated VEGF-A promoter activity, expression and secretion in tumour cells. PKD2 depletion in pancreatic tumours inhibited tumour-driven blood vessel formation and tumour growth in the CAM and in orthotopic pancreatic cancer xenografts., Conclusion: PKD2 regulates hypoxia-induced VEGF-A expression/secretion by tumour cells and VEGF-A stimulated blood vessel formation. PKD2 is a novel, essential mediator of tumour cell-endothelial cell communication and a promising therapeutic target to inhibit angiogenesis in gastrointestinal cancers.
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- 2010
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30. Plasmin triggers chemotaxis of monocyte-derived dendritic cells through an Akt2-dependent pathway and promotes a T-helper type-1 response.
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Li X, Syrovets T, Genze F, Pitterle K, Oberhuber A, Orend KH, and Simmet T
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- Annexin A2 metabolism, Aorta metabolism, Aorta pathology, Atherosclerosis metabolism, Atherosclerosis pathology, Cell Movement drug effects, Chemotaxis drug effects, Dendritic Cells pathology, Fibrinolysin pharmacology, Humans, Mitogen-Activated Protein Kinase Kinases metabolism, Monocytes pathology, T-Lymphocytes, Helper-Inducer metabolism, T-Lymphocytes, Helper-Inducer pathology, Chemotaxis physiology, Dendritic Cells metabolism, Fibrinolysin metabolism, Monocytes metabolism, Proto-Oncogene Proteins c-akt metabolism, Signal Transduction physiology
- Abstract
Objective: Dendritic cells (DC) accumulate in atherosclerotic arteries where they can modulate atherogenesis. We investigated whether plasmin might alter the function of human DC., Methods and Results: Stimulation of monocyte-derived DC with plasmin elicited a time-dependent actin polymerization and chemotaxis comparable to that triggered by the standard chemoattractant formyl-methionyl-leucyl-phenylalanine. Plasmin triggered rapid activation of Akt and mitogen-activated protein kinases, followed by phosphorylation of the regulatory myosin light chain and chemotaxis. For the chemotactic DC migration, the activation of Akt and p38 and extracellular signal-regulated kinase 1/2 mitogen-activated protein kinases were indispensable, as shown by pharmacological inhibitors. DC express Akt1 and Akt2, but not Akt3. However, in DC, plasmin activates exclusively Akt2 via a p38 mitogen-activated protein kinase-dependent pathway. Accordingly, knockdown of Akt2 with short-hairpin RNA, but not of Akt1, blocked the plasmin-induced extracellular signal-regulated kinase 1/2 activation and the chemotactic response. Moreover, plasmin-stimulated DC induced polarization of CD4(+) T cells toward the interferon-gamma-producing, proinflammatory Th1 phenotype. Consistent with a role for DC and adaptive immune response in atherogenesis, we demonstrate DC in human atherosclerotic vessels and show that plasmin is abundant in human atherosclerotic lesions, where it colocalizes with DC., Conclusions: Plasmin generation in the atherosclerotic vessel wall might contribute to accumulation of DC, activation of the adaptive immune response, and aggravation of atherosclerosis.
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- 2010
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31. Specific induction of migration and invasion of pancreatic carcinoma cells by RhoC, which differs from RhoA in its localisation and activity.
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Dietrich KA, Schwarz R, Liska M, Grass S, Menke A, Meister M, Kierschke G, Längle C, Genze F, and Giehl K
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- Cell Line, Tumor, Deep Brain Stimulation, Humans, Pancreatic Neoplasms metabolism, Protein Isoforms chemistry, Protein Isoforms genetics, Protein Isoforms metabolism, RNA, Messenger metabolism, Reverse Transcriptase Polymerase Chain Reaction, rap GTP-Binding Proteins chemistry, rap GTP-Binding Proteins genetics, rap GTP-Binding Proteins metabolism, rho GTP-Binding Proteins chemistry, rho GTP-Binding Proteins genetics, rhoA GTP-Binding Protein chemistry, rhoA GTP-Binding Protein genetics, rhoC GTP-Binding Protein, Cell Movement, Neoplasm Invasiveness, Pancreatic Neoplasms pathology, rho GTP-Binding Proteins metabolism, rhoA GTP-Binding Protein metabolism
- Abstract
RhoA and RhoC are highly related Rho GTPases, but differentially control cellular behaviour. We combined molecular, cellular, and biochemical experiments to characterise differences between these highly similar GTPases. Our findings demonstrate that enhanced expression of RhoC results in a striking increase in the migration and invasion of pancreatic carcinoma cells, whereas forced expression of RhoA decreases these actions. These isoform-specific functions correlate with differences in the cellular activity of RhoA and RhoC in human cells, with RhoC being more active than RhoA in activity assays and serum-response factor-dependent gene transcription. Subcellular localisation studies revealed that RhoC is predominantly localised in the membrane-containing fraction, whereas RhoA is mainly localised in the cytoplasmic fraction. These differences are not mediated by a different interaction with RhoGDIs. In vitro GTP/GDP binding analyses demonstrate different affinity of RhoC for GTP[S] and faster intrinsic and guanine nucleotide exchange factor (GEF)-stimulated GDP/GTP exchange rates compared to RhoA. Moreover, the catalytic domains of SopE and Dbs are efficacious GEFs for RhoC. mRNA expression of RhoC is markedly enhanced in advanced pancreatic cancer stages, and thus the differences discovered between RhoA and RhoC might provide explanations for their different influences on cell migration and tumour invasion.
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- 2009
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32. Small molecule XIAP inhibitors enhance TRAIL-induced apoptosis and antitumor activity in preclinical models of pancreatic carcinoma.
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Vogler M, Walczak H, Stadel D, Haas TL, Genze F, Jovanovic M, Bhanot U, Hasel C, Möller P, Gschwend JE, Simmet T, Debatin KM, and Fulda S
- Subjects
- Animals, Carcinoma, Pancreatic Ductal metabolism, Carcinoma, Pancreatic Ductal pathology, Caspase 3 metabolism, Drug Synergism, Enzyme Activation, Female, HCT116 Cells, Humans, Mice, Mice, Nude, Mitochondria drug effects, Mitochondria metabolism, Pancreatic Neoplasms metabolism, Pancreatic Neoplasms pathology, TNF-Related Apoptosis-Inducing Ligand administration & dosage, X-Linked Inhibitor of Apoptosis Protein biosynthesis, Xenograft Model Antitumor Assays, Antineoplastic Combined Chemotherapy Protocols pharmacology, Apoptosis drug effects, Carcinoma, Pancreatic Ductal drug therapy, Pancreatic Neoplasms drug therapy, TNF-Related Apoptosis-Inducing Ligand pharmacology, X-Linked Inhibitor of Apoptosis Protein antagonists & inhibitors
- Abstract
Evasion of apoptosis is a characteristic feature of pancreatic cancer, a prototypic cancer that is refractory to current treatment approaches. Hence, there is an urgent need to design rational strategies that counter apoptosis resistance. To explore X-linked inhibitor of apoptosis (XIAP) as a therapeutic target in pancreatic cancer, we analyzed the expression of XIAP in pancreatic tumor samples and evaluated the effect of small molecule XIAP inhibitors alone and in combination with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) against pancreatic carcinoma in vitro and in vivo. Here, we report that XIAP is highly expressed in pancreatic adenocarcinoma samples compared with normal pancreatic ducts. Small molecule XIAP inhibitors synergize with TRAIL to induce apoptosis and to inhibit long-term clonogenic survival of pancreatic carcinoma cells. In contrast, they do not reverse the lack of toxicity of TRAIL on nonmalignant cells in vitro or normal tissues in vivo, pointing to a therapeutic index. Most importantly, XIAP inhibitors cooperate with TRAIL to trigger apoptosis and suppress pancreatic carcinoma growth in vivo in two preclinical models, i.e., the chorioallantoic membrane model and a mouse xenograft model. Parallel immunohistochemical analysis of tumor tissue under therapy reveals that the XIAP inhibitor acts in concert with TRAIL to cause caspase-3 activation and apoptosis. In conclusion, our findings provide, for the first time, evidence in vivo that XIAP inhibitors prime pancreatic carcinoma cells for TRAIL-induced apoptosis and potentiate the antitumor activity of TRAIL against established pancreatic carcinoma. These findings build the rationale for further (pre)clinical development of XIAP inhibitors and TRAIL against pancreatic cancer.
- Published
- 2009
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33. Targeting XIAP bypasses Bcl-2-mediated resistance to TRAIL and cooperates with TRAIL to suppress pancreatic cancer growth in vitro and in vivo.
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Vogler M, Walczak H, Stadel D, Haas TL, Genze F, Jovanovic M, Gschwend JE, Simmet T, Debatin KM, and Fulda S
- Subjects
- Adenocarcinoma pathology, Animals, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Chick Embryo, Drug Resistance, Neoplasm drug effects, Drug Synergism, Female, Humans, Mice, Mice, Nude, Pancreatic Neoplasms pathology, RNA, Small Interfering pharmacology, Tumor Cells, Cultured, X-Linked Inhibitor of Apoptosis Protein genetics, Xenograft Model Antitumor Assays, Adenocarcinoma drug therapy, Cell Proliferation drug effects, Drug Resistance, Neoplasm genetics, Genes, bcl-2 physiology, Pancreatic Neoplasms drug therapy, RNA, Small Interfering administration & dosage, TNF-Related Apoptosis-Inducing Ligand administration & dosage, X-Linked Inhibitor of Apoptosis Protein antagonists & inhibitors
- Abstract
Resistance to apoptosis is a hallmark of pancreatic cancer, a leading cause of cancer deaths. Therefore, novel strategies are required to target apoptosis resistance. Here, we report that the combination of X-linked inhibitor of apoptosis (XIAP) inhibition and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an effective approach to trigger apoptosis despite Bcl-2 overexpression and to suppress pancreatic cancer growth in vitro and in vivo. Knockdown of XIAP by RNA interference cooperates with TRAIL to induce caspase activation, loss of mitochondrial membrane potential, cytochrome c release, and apoptosis in pancreatic carcinoma cells. Loss of mitochondrial membrane potential and cytochrome c release are extensively inhibited by a broad range or caspase-3 selective caspase inhibitor and by RNAi-mediated silencing of caspase-3, indicating that XIAP inhibition enhances TRAIL-induced mitochondrial damage in a caspase-3-dependent manner. XIAP inhibition combined with TRAIL even breaks Bcl-2-imposed resistance by converting type II cells that depend on the mitochondrial contribution to the death receptor pathway to type I cells in which TRAIL-induced activation of caspase-3 and caspase-9 and apoptosis proceeds irrespective of high Bcl-2 levels. Most importantly, XIAP inhibition potentiates TRAIL-induced antitumor activity in two preclinical models of pancreatic cancer in vivo. In the chicken chorioallantoic membrane model, XIAP inhibition significantly enhances TRAIL-mediated apoptosis and suppression of tumor growth. In a tumor regression model in xenograft-bearing mice, XIAP inhibition acts in concert with TRAIL to cause even regression of established pancreatic carcinoma. Thus, this combination of XIAP inhibition plus TRAIL is a promising strategy to overcome apoptosis resistance of pancreatic cancer that warrants further investigation.
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- 2008
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34. Antiinflammatory and antiatherogenic effects of the NF-kappaB inhibitor acetyl-11-keto-beta-boswellic acid in LPS-challenged ApoE-/- mice.
- Author
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Cuaz-Pérolin C, Billiet L, Baugé E, Copin C, Scott-Algara D, Genze F, Büchele B, Syrovets T, Simmet T, and Rouis M
- Subjects
- Animals, Atherosclerosis genetics, Boswellia, Cells, Cultured, Disease Models, Animal, Inflammation drug therapy, Lipopolysaccharides administration & dosage, Lipopolysaccharides immunology, Mice, Mice, Knockout, Apolipoproteins E genetics, Atherosclerosis drug therapy, NF-kappa B antagonists & inhibitors, NF-kappa B drug effects, Plant Extracts pharmacology, Triterpenes pharmacology
- Abstract
Objective: In this article, we studied the effect of acetyl-11-keto-beta-boswellic acid (AKbetaBA), a natural inhibitor of the proinflammatory transcription factor NF-kappaB on the development of atherosclerotic lesions in apolipoprotein E-deficient (apoE-/-) mice., Methods and Results: Atherosclerotic lesions were induced by weekly LPS injection in apoE-/- mice. LPS alone increased atherosclerotic lesion size by approximately 100%, and treatment with AKbetaBA significantly reduced it by approximately 50%. Moreover, the activity of NF-kappaB was also reduced in the atherosclerotic plaques of LPS-injected apoE-/- mice treated with AKbetaBA. As a consequence, AKbetaBA treatment led to a significant downregulation of several NF-kappaB-dependent genes such as MCP-1, MCP-3, IL-1alpha, MIP-2, VEGF, and TF. By contrast, AKbetaBA did not affect the plasma concentrations of triglycerides, total cholesterol, antioxidized LDL antibodies, and various subsets of lymphocyte-derived cytokines. Moreover, AKbetaBA potently inhibited the IkappaB kinase (IKK) activity immunoprecipitated from LPS-stimulated mouse macrophages and mononuclear cells leading to decreased phosphorylation of IkappaB alpha and inhibition of p65/NF-kappaB activation. Comparable AKbetaBA-mediated inhibition was also observed in LPS-stimulated human macrophages., Conclusions: The inhibition of NF-kappaB activity by plant resins from species of the Boswellia family might represent an alternative for classical medicine treatments for chronic inflammatory diseases such as atherosclerosis.
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- 2008
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35. Antagonistic effects of sodium butyrate and N-(4-hydroxyphenyl)-retinamide on prostate cancer.
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Kuefer R, Genze F, Zugmaier W, Hautmann RE, Rinnab L, Gschwend JE, Angelmeier M, Estrada A, and Buechele B
- Subjects
- Animals, Butyrates antagonists & inhibitors, Butyrates pharmacokinetics, Cell Line, Tumor, Cell Proliferation drug effects, Chickens, Chorioallantoic Membrane drug effects, Dose-Response Relationship, Drug, Fenretinide antagonists & inhibitors, Fenretinide pharmacokinetics, Humans, Male, Mitogen-Activated Protein Kinases drug effects, Mitogen-Activated Protein Kinases physiology, Neoplasm Transplantation, Prostatic Neoplasms pathology, Transplantation, Heterologous, Butyrates pharmacology, Fenretinide pharmacology, Prostatic Neoplasms drug therapy
- Abstract
Butyrates and retinoids are promising antineoplastic agents. Here we analyzed effects of sodium butyrate and N-(4-hydroxyphenyl)-retinamide (4-HPR) on prostate cancer cells as monotherapy or in combination in vitro and in vivo. Sodium butyrate and 4-HPR induced concentration-dependent growth inhibition in prostate cancer cells in vitro. The isobologram analysis revealed that sodium butyrate and 4-HPR administered together antagonize effects of each other. For the in vivo studies, a water-soluble complex (4-HPR with a cyclodextrin) was created. A single dose of sodium butyrate and 4-HPR showed a peak level in chicken plasma within 30 minutes. Both compounds induced inhibition of proliferation and apoptosis in xenografts of the chicken chorioallantoic membrane. Analysis of the cytotoxic effects of the drugs used in combination demonstrated an antagonistic effect on inhibition of proliferation and on induction of apoptosis. Prolonged jun N-terminal kinase phosphorylation induced by sodium butyrate and 4-HPR was strongly attenuated when both compounds were used in combination. Both compounds induced inhibition of NF-kappaB. This effect was strongly antagonized in LNCaP cells when the compounds were used in combination. These results indicate that combinational therapies have to be carefully investigated due to potential antagonistic effects in the clinical setting despite promising results of a monotherapy.
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- 2007
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36. Characterization of 3alpha-acetyl-11-keto-alpha-boswellic acid, a pentacyclic triterpenoid inducing apoptosis in vitro and in vivo.
- Author
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Büchele B, Zugmaier W, Estrada A, Genze F, Syrovets T, Paetz C, Schneider B, and Simmet T
- Subjects
- Antineoplastic Agents, Phytogenic administration & dosage, Antineoplastic Agents, Phytogenic therapeutic use, Cell Line, Tumor drug effects, Drug Resistance, Neoplasm, Humans, Male, Plant Extracts administration & dosage, Plant Extracts therapeutic use, Prostatic Neoplasms drug therapy, Triterpenes administration & dosage, Triterpenes pharmacology, Triterpenes therapeutic use, Antineoplastic Agents, Phytogenic pharmacology, Apoptosis drug effects, Boswellia, Phytotherapy, Plant Extracts pharmacology
- Abstract
3Alpha-acetyl-11-keto-alpha-boswellic acid (3alpha-acetoxy-11-oxo-olean-12-en-24-oic acid, 1) was synthesized by a radical-type reaction using bromine and 3alpha-acetyl-alpha-boswellic acid isolated from the oleo-gum-resin of Boswellia carterii. 1D and 2D NMR (COSY, HMBC, ROESY) at 500 MHz were used for shift assignments and structure verification. The compound investigated is present in a herbal preparation extracted from Boswellia serrata oleo-gum-resin, it inhibits the growth of chemotherapy-resistant human PC-3 prostate cancer cells in vitro and induces apoptosis as shown by activation of caspase 3 and the induction of DNA fragmentation. In addition, compound 1 is active IN VIVO as shown by inhibition of proliferation and induction of apoptosis in PC-3 prostate cancer cells xenotransplanted onto the chick chorioallantoic membrane.
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- 2006
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37. Oncogenic K-Ras down-regulates Rac1 and RhoA activity and enhances migration and invasion of pancreatic carcinoma cells through activation of p38.
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Dreissigacker U, Mueller MS, Unger M, Siegert P, Genze F, Gierschik P, and Giehl K
- Subjects
- Animals, Chickens, Cytoskeleton pathology, Enzyme Activation, Green Fluorescent Proteins metabolism, Humans, JNK Mitogen-Activated Protein Kinases metabolism, Neoplasm Invasiveness, Neoplasm Metastasis, Protein Transport, Cell Movement, Down-Regulation genetics, Oncogene Protein p21(ras) metabolism, Pancreatic Neoplasms pathology, p38 Mitogen-Activated Protein Kinases metabolism, rac1 GTP-Binding Protein metabolism, rhoA GTP-Binding Protein metabolism
- Abstract
Activating mutations in the K-ras gene are genetic alterations frequently found in human carcinomas, particularly in pancreatic adenocarcinomas. Mutation of the K-ras gene is thought to be an early and important event in pancreatic tumor initiation, but the precise role of the mutant K-Ras proteins in neoplastic progression is still unknown. In the present study, we have characterized the influence of oncogenic K-Ras on the phenotype and on the signal transduction of epitheloid PANC-1 pancreatic carcinoma cells by generating PANC-1 cell clones, which stably express EGFP(enhanced green fluorescent protein)-K-Ras (V12). EGFP-K-Ras (V12)-expressing cells exhibited a more fibroblastoid cellular phenotype with irregular cell shape and disorganized cytokeratin filaments. Moreover, these cells showed a marked enhancement of their migratory and invasive properties. Stable expression of EGFP-K-Ras (V12) down-regulated the activity of Rac1 and RhoA, resulting in reduced subcortical actin filaments and stress fibers, which might contribute to the epithelial dedifferentiation. Characterization of the activity of mitogen-activated protein kinases revealed that EGFP-K-Ras (V12) enhanced the activity of p38, but did not affect the activities of the Raf/MEK/ERK cascade and JNK. While inhibition of either MEK or JNK activity had no effect on EGFP-K-Ras (V12)-induced migration, inhibition of p38 activity markedly reduced EGFP-K-Ras (V12)-induced migration. Collectively, the results suggest that oncogenic K-Ras enhances the malignant phenotype and identify the mitogen-activated protein kinase p38 as a target to inhibit oncogenic K-Ras-induced pancreatic tumor cell migration.
- Published
- 2006
- Full Text
- View/download PDF
38. High-performance liquid chromatographic determination of acetyl-11-keto-alpha-boswellic acid, a novel pentacyclic triterpenoid, in plasma using a fluorinated stationary phase and photodiode array detection: application in pharmacokinetic studies.
- Author
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Büchele B, Zugmaier W, Genze F, and Simmet T
- Subjects
- Animals, Chick Embryo, Sensitivity and Specificity, Triterpenes pharmacokinetics, Chromatography, High Pressure Liquid methods, Fluorine chemistry, Triterpenes blood
- Abstract
A rapid, sensitive and selective HPLC separation with photodiode array detection was developed for the analysis of the novel pentacyclic triterpenoid acetyl-11-keto-alpha-boswellic acid. Complete baseline separation of acetyl-11-keto-alpha-boswellic acid from the corresponding isomer acetyl-11-keto-beta-boswellic acid was achieved on a fluorinated stationary phase. The standard curve was linear from 0.98 nmol/l to 196 nmol/l acetyl-11-keto-alpha-boswellic acid. The compound was isolated from chick embryonic plasma using extraction on diatomaceous earth with an overall average extraction yield of 82%. This method was applied in a kinetic study on the chick chorioallantoic membrane model (CAM) and showed unequivocal separation between acetyl-11-keto-alpha-boswellic acid and acetyl-11-keto-beta-boswellic acid unachievable so far.
- Published
- 2005
- Full Text
- View/download PDF
39. Inhibition of clonogenic tumor growth: a novel function of Smac contributing to its antitumor activity.
- Author
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Vogler M, Giagkousiklidis S, Genze F, Gschwend JE, Debatin KM, and Fulda S
- Subjects
- Antibiotics, Antineoplastic pharmacology, Apoptosis Regulatory Proteins, Blotting, Western, Carcinoma metabolism, Carcinoma pathology, Caspases metabolism, Cell Count, Cell Cycle, Cell Division drug effects, Cell Line, Tumor, Cell Movement drug effects, Colonic Neoplasms metabolism, Colonic Neoplasms pathology, Cytosol metabolism, Doxorubicin pharmacology, Glioblastoma metabolism, Glioblastoma pathology, Humans, Intracellular Signaling Peptides and Proteins pharmacology, Mitochondria metabolism, Mitochondrial Proteins genetics, Mitochondrial Proteins pharmacology, Neuroblastoma metabolism, Neuroblastoma pathology, Pancreatic Neoplasms metabolism, Pancreatic Neoplasms pathology, Proteins antagonists & inhibitors, X-Linked Inhibitor of Apoptosis Protein antagonists & inhibitors, beta-Galactosidase metabolism, Apoptosis drug effects, Cell Proliferation drug effects, Cell Survival drug effects, Gene Expression Regulation, Neoplastic drug effects, Intracellular Signaling Peptides and Proteins metabolism, Mitochondrial Proteins metabolism
- Abstract
While second mitochondria derived activator of caspase (Smac) has been described to sensitize for apoptosis, its effect on cell viability in the absence of apoptotic stimuli has remained unclear. Here, we report that Smac inhibits clonogenic tumor growth by blocking random migration and proliferation and by enhancing apoptosis in a cell density and cell type dependent manner in SH-EP neuroblastoma cells. Inhibition of clonogenic survival by overexpression of full-length or processed Smac strictly depended on low cell density, and was reversible by replatement at high density. We discovered that Smac inhibits cell motility and random migration at low cell density. In addition, Smac enhanced apoptosis and inhibited protein, but not mRNA expression of XIAP, survivin and other short-lived proteins (FLIP, p21), indicating that Smac may globally inhibit protein expression. Also, Smac inhibited proliferation and increased polynucleation with no evidence for polyploidy, cell cycle arrest or senescence indicating that Smac impaired cell division. Interestingly, inhibition of clonogenic capacity by Smac occurred independent of its apoptosis promoting activity. By demonstrating that Smac restrains clonogenic tumor growth, our findings may have important implications for control of tumor growth and/or its metastatic spread. Thus, Smac agonists may be useful in cancer therapy, for example, for tumor control in minimal residual disease. Oncogene (2005) 24, 7190-7202. doi:10.1038/sj.onc.1208876; published online 8 August 2005., (Oncogene (2005) 24, 7190-7202. doi:10.1038/sj.onc.1208876; published online 8 August 2005.)
- Published
- 2005
- Full Text
- View/download PDF
40. Inhibition of IkappaB kinase activity by acetyl-boswellic acids promotes apoptosis in androgen-independent PC-3 prostate cancer cells in vitro and in vivo.
- Author
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Syrovets T, Gschwend JE, Büchele B, Laumonnier Y, Zugmaier W, Genze F, and Simmet T
- Subjects
- Animals, Cell Line, Tumor, Cell Proliferation drug effects, Chick Embryo, Chorioallantoic Membrane, Cyclodextrins pharmacology, Fibroblasts, I-kappa B Kinase, Male, Mice, Mice, Nude, NF-kappa B metabolism, Neoplasm Invasiveness, Prostatic Neoplasms metabolism, Protein Serine-Threonine Kinases metabolism, Signal Transduction drug effects, Xenograft Model Antitumor Assays, Androgens metabolism, Apoptosis drug effects, Prostatic Neoplasms enzymology, Prostatic Neoplasms pathology, Protein Serine-Threonine Kinases antagonists & inhibitors, Triterpenes pharmacology
- Abstract
Signaling through NF-kappaB has been implicated in the malignant phenotype as well as the chemoresistance of various cancers. Here we show that the natural compounds acetyl-beta-boswellic acid and acetyl-11-keto-beta-boswellic acid (AKbetaBA) inhibit proliferation and elicit cell death in chemoresistant androgen-independent PC-3 prostate cancer cells in vitro and in vivo. Induction of apoptosis was demonstrated in cultured PC-3 cells by several parameters including mitochondrial cytochrome c release and DNA fragmentation. At the molecular level these compounds inhibit constitutively activated NF-kappaB signaling by intercepting the IkappaB kinase (IKK) activity; signaling through the interferon-stimulated response element remained unaffected, suggesting specificity for IKK inhibition. The impaired phosphorylation of p65 and the reduced nuclear translocation of NF-kappaB proteins were associated with down-regulation of the constitutively overexpressed and NF-kappaB-dependent antiapoptotic proteins Bcl-2 and Bcl-x(L). In addition, expression of cyclin D1, a crucial cell cycle regulator, was reduced as well. Down-regulation of IKK by antisense oligodeoxynucleotides confirmed the essential role of IKK inhibition for the proliferation of the PC-3 cells. Both compounds tested were active in vivo, yet AKbetaBA proved to be far superior. Indeed, topical application of water-soluble AKbetaBA-gamma-cyclodextrin on PC-3 tumors xenografted onto chick chorioallantoic membranes induced concentration-dependent inhibition of proliferation as well as apoptosis. Similarly, in nude mice carrying PC-3 tumors, systemic application of AKbetaBA-gamma-cyclodextrin inhibited tumor growth and triggered apoptosis in the absence of detectable systemic toxicity. Thus, AKbetaBA and related compounds acting on IKK might provide a novel approach for the treatment of chemoresistant human tumors such as androgen-independent human prostate cancers.
- Published
- 2005
- Full Text
- View/download PDF
41. Activation of phosphatidylinositol 3-kinase and extracellular signal-regulated kinase is required for glial cell line-derived neurotrophic factor-induced migration and invasion of pancreatic carcinoma cells.
- Author
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Veit C, Genze F, Menke A, Hoeffert S, Gress TM, Gierschik P, and Giehl K
- Subjects
- Cell Movement, Enzyme Activation, Enzyme Inhibitors pharmacology, GTP Phosphohydrolases metabolism, Genes, Dominant, Genes, ras physiology, Glial Cell Line-Derived Neurotrophic Factor, Humans, MAP Kinase Kinase 1, MAP Kinase Kinase 4, Mitogen-Activated Protein Kinase Kinases antagonists & inhibitors, Mitogen-Activated Protein Kinase Kinases metabolism, Protein Serine-Threonine Kinases metabolism, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-akt, Proto-Oncogene Proteins c-raf metabolism, Signal Transduction, Tumor Cells, Cultured, JNK Mitogen-Activated Protein Kinases, Mitogen-Activated Protein Kinases metabolism, Neoplasm Invasiveness, Nerve Growth Factors metabolism, Pancreatic Neoplasms metabolism, Pancreatic Neoplasms pathology, Phosphatidylinositol 3-Kinases metabolism
- Abstract
Pancreatic carcinoma cells exhibit a pronounced tendency to invade along and into intra- and extrapancreatic nerves, even at early stages of the disease. The neurotrophic factor glial cell line-derived neurotrophic factor (GDNF) has been shown to promote pancreatic cancer cell invasion. Here, we demonstrate that pancreatic carcinoma cell lines, such as PANC-1, expressed the RET and GDNF family receptor alpha receptor components for GDNF and that primary pancreatic tumor samples, derived from carcinomas with regional lymph node metastasis, exhibited marked expression of the mRNA encoding the RET51 isoform. Moreover, GDNF was an efficacious and potent chemoattractant for pancreatic carcinoma cells as examined in in vitro and in vivo model systems. Treatment of PANC-1 cells with GDNF resulted in activation of the monomeric GTPases N-Ras, Rac1, and RhoA, in activation of the mitogen-activated protein kinases extracellular signal-regulated kinase (ERK) and c-Jun NH(2)-terminal kinase (JNK) and in activation of the phosphatidylinositol 3-kinase/Akt pathway. Both inhibition of the Ras-Raf-MEK (mitogen-activated protein/ERK kinase)-ERK cascade by either stable expression of dominant-negative H-Ras(N17) or addition of the MEK1 inhibitor PD98059 as well as inhibition of the phosphatidylinositol 3-kinase pathway by LY294002 prevented GDNF-induced migration and invasion of PANC-1 cells. These results demonstrate that pancreatic tumor cell migration and possibly perineural invasion in response to GDNF is critically controlled by activation of the Ras-Raf-MEK-ERK and the phosphatidylinositol 3-kinase pathway.
- Published
- 2004
- Full Text
- View/download PDF
42. Chorioallantoic membrane assay: vascularized 3-dimensional cell culture system for human prostate cancer cells as an animal substitute model.
- Author
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Kunzi-Rapp K, Genze F, Küfer R, Reich E, Hautmann RE, and Gschwend JE
- Subjects
- Animals, Chick Embryo, Humans, Male, Allantois, Cell Culture Techniques methods, Chorion, Prostatic Neoplasms pathology
- Abstract
Purpose: Chorioallantoic membranes have been used as a reliable biomedical assay system for many years. Chicken eggs in the early phase of breeding are between in vitro and in vivo systems but may provide an immunodeficient, vascularized test environment. We tested this model as an in vivo system for prostate cancer research., Materials and Methods: Single cell suspensions of LNCaP, PC-3 and Tsu-Pr1 human prostatic cancer cell lines as well as 2 immortalized normal human prostate epithelial cell lines were inoculated on the chorioallantoic membrane of fertilized chicken eggs on day 5 or 6 of breeding. Tumor growth and viability of the embryo was evaluated by stereo microscopy. At day 10 the membranes were removed and embedded in paraffin. Cell morphology was assessed after hematoxylin and eosin staining. Cellular expression of cytokeratin, prostate specific antigen and androgen receptor as well as apoptosis induction was confirmed by immunohistochemistry., Results: Three days after tumor cell inoculation on the extraembryonic vascular system of the chorioallantoic membrane cell growth and formation of 3-dimensional tumors became apparent in 100% of inoculated membranes. Strong neo-angiogenesis was detected next to the established tumors and tumor cells invading the stroma of the chorioallantoic membrane. Cytokeratin expression as well as prostate specific antigen and androgen receptor in LNCaP cells confirmed the human prostate tumor origin. Assessment of quantitative in vivo apoptosis induction in LNCaP cells after intravenous injection of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate confirmed the model as a versatile in vivo system., Conclusions: The well vascularized chorioallantoic membrane of bred chicken eggs is a suitable system for early in vivo cancer research. Reliable growth of prostate cancer cell lines is feasible and allows the evaluation of proliferation and apoptosis induction after intravascular or topic application of anticancer drugs. Exploitation of this assay enables a substantial reduction in or substitution for subsequent animal experiments.
- Published
- 2001
- Full Text
- View/download PDF
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