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Research Interests: Cancer, Apoptosis, Caspases, Humans, Mice, and 9 moreFemale, Animals, Cell Death, Zingiberaceae, Anticancer, Apoptose, Plant extracts, Biological activity, and Extract
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Carcinoids are rare tumors derived from enterochromaffin (EC) cells of the embryonic neural crest. They have malignant potential and their incidence is steadily increasing. The only curative treatment option is surgery. We have focused on... more
Carcinoids are rare tumors derived from enterochromaffin (EC) cells of the embryonic neural crest. They have malignant potential and their incidence is steadily increasing. The only curative treatment option is surgery. We have focused on cultivation of human neuroendocrine tumors (NET) as relevant models for the study of potential therapy. Only a few cell lines from human carcinoids have been established so far, among them our earlier KRJ-I cell line from a human ileal carcinoid. The reason for the poor success in establishing carcinoid cell lines is due to the small amount of tissue available and the low mitotic activity in primary cultures. We have successfully established three continuously growing cell lines from tissue obtained from a metastatic human carcinoid of the terminal ileum (midgut carcinoid): P-STS was derived from the primary tumor, L-STS from a lymph node metastasis and H-STS from a hepatic metastasis. Immunocytochemistry proved the maintenance of characteristic ne...
Research Interests: Cancer and Anticancer
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Research Interests: Immune response, Computational Biology, Cell Cycle, Multidisciplinary, Signal Transduction, and 20 moreSerotonin, Cell line, Humans, G protein-coupled receptors, cyclic AMP, Scale-Free Networks, Gene Network, Phosphorylation, Gene Regulatory Networks, PLoS one, Very high throughput, Reproducibility of Results, Nervous System, Neuroendocrine Tumor, In Vitro Studies, Expression analysis, Neuroendocrine Tumors, Response Elements, Small Intestine, and Differential expression
Medullary thyroid carcinoma (MTC) is a calcitonin-producing tumor of the thyroid arising from the parafollicular C-cells. MTC is poorly responsive to chemotherapy and radiotherapy, hence the only effective therapy is surgery. Based on... more
Medullary thyroid carcinoma (MTC) is a calcitonin-producing tumor of the thyroid arising from the parafollicular C-cells. MTC is poorly responsive to chemotherapy and radiotherapy, hence the only effective therapy is surgery. Based on this fact, alternative strategies have been sought. The effects of Cautleya gracilis (Smith) Dandy were investigated for the first time in three human MTC cell lines and in MTC-transplanted mice. Proliferation and viability were quantified by cell counting, WST-1 tests, and ATP luminescent cell viability assays. Apoptosis was studied by DAPI staining, flow cytometry and luminescent assays for caspases 3/7, 8 and 9. A dose-dependent reduction of proliferation and an induction of apoptosis were found in all MTC cell lines, while normal fibroblasts were not impaired. Similar tumor inhibition was seen in heterotransplanted mice. Our in vitro and in vivo findings suggest a new potential clinical effect of Cautleya.
Research Interests: Cancer, Apoptosis, Caspases, Humans, Mice, and 9 moreFemale, Animals, Cell Death, Zingiberaceae, Anticancer, Apoptose, Plant extracts, Biological activity, and Extract
Carcinoids are rare tumors derived from enterochromaffin (EC) cells of the embryonic neural crest. They have malignant potential and their incidence is steadily increasing. The only curative treatment option is surgery. We have focused on... more
Carcinoids are rare tumors derived from enterochromaffin (EC) cells of the embryonic neural crest. They have malignant potential and their incidence is steadily increasing. The only curative treatment option is surgery. We have focused on cultivation of human neuroendocrine tumors (NET) as relevant models for the study of potential therapy. Only a few cell lines from human carcinoids have been established so far, among them our earlier KRJ-I cell line from a human ileal carcinoid. The reason for the poor success in establishing carcinoid cell lines is due to the small amount of tissue available and the low mitotic activity in primary cultures. We have successfully established three continuously growing cell lines from tissue obtained from a metastatic human carcinoid of the terminal ileum (midgut carcinoid): P-STS was derived from the primary tumor, L-STS from a lymph node metastasis and H-STS from a hepatic metastasis. Immunocytochemistry proved the maintenance of characteristic ne...
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Small intestinal (SI) neuroendocrine tumors (NETs) are rare neoplasms derived from neuroendocrine cells presenting distinct clinical symptoms according to the ability to secrete neuroamines. Nevertheless, many are asymptomatic and... more
Small intestinal (SI) neuroendocrine tumors (NETs) are rare neoplasms derived from neuroendocrine cells presenting distinct clinical symptoms according to the ability to secrete neuroamines. Nevertheless, many are asymptomatic and misdiagnosed. As response rates to chemotherapy are low, surgery remains the only effective treatment. Because many tumors have metastasized at the time of diagnosis, curative surgery is rarely achieved. Consequently, a substantial need for new therapeutic options has emerged. The effects of novel plant extracts from Trailliaedoxa gracilis (W.W. Smith & Forrest) were investigated in the SI-NET cell line KRJ-I and in KRJ-I transplanted mice. Proliferation and viability were analyzed using cell counting and WST-1 cell proliferation assay. Apoptosis was determined by DAPI staining and electron microscopy, and quantified by luminescence assays for caspases 3/7, 6, 8, 9 and 2. Extracts of Trailliaedoxa gracilis showed a dose-dependent reduction of proliferation...
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Research Interests: Clinical Trial, Cancer, Neuroendocrinology, Prediction, Stratification, and 22 moreHumans, Models, Female, Male, Heart Disease, External Validity, Clinical Sciences, Aged, Middle Aged, Digestive System, Kaplan-Meier, Prognosis, Management Strategy, National Cancer Institute, Neuroendocrine Tumor, Indexation, Database, Neuroendocrine Tumors, Neurosciences, Proportional Hazards Models, Small Intestine, and Chromogranin A
Research Interests: Risk assessment, Colorectal cancer, Serotonin, Somatostatin, Humans, and 16 moreFemale, Male, Clinical Sciences, Prevalence, Survival Rate, Prognosis, Gastrointestinal Tract, Risk Assessment, Management Strategy, Neuroendocrine Tumor, Clinical Presentation, Chromosomal abnormalities, Neuroendocrine Tumors, Tyrosine Kinase, Chromogranin A, and Enterochromaffin cell
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In this study we demonstrate anticancer activity of novel fully water soluble cationic porphyrins. The two cationic porphyrins 5,10,15-tris(N-methylpyridinium-4-yl)-20-[1-phenyl-4-(3-N-phenylsulfonylindolyl)]-21H,23H-porphyrin chloride... more
In this study we demonstrate anticancer activity of novel fully water soluble cationic porphyrins. The two cationic porphyrins 5,10,15-tris(N-methylpyridinium-4-yl)-20-[1-phenyl-4-(3-N-phenylsulfonylindolyl)]-21H,23H-porphyrin chloride (TMPy(3)PhenIndolprot(1)P-Cl(3)) and 5-{5-[2-(9,9-Dimethyl)fluorenyl]-N-methylpyridinium-3-yl}-10,15,20-tris(N-methyl-pyridinium-4-yl)-21H,23H-porphyrin chloride (TMPy(3)PyFluorenyl(1)P-Cl(4)) were prepared and their antiproliferative effects were studied in two human tumor cell lines and a normal human fibroblast cell line. Effects of the novel porphyrin compounds were evaluated in the small intestinal neuroendocrine tumor cell line KRJ-I, the medullary thyroid carcinoma cell line MTC-SK and the normal human fibroblast cell line HF-SAR by cell counting, cell proliferation assays and cell cytotoxicity analyses. TMPy(3)PhenIndolprot(1)P-Cl(3) and TMPy(3)PyFluorenyl(1)P-Cl(4) showed antiproliferative effects in the tumor cell lines MTC-SK and KRJ-I; cell viability was decreased and cytotoxic effects were quantified, while no significant alterations of the human fibroblasts were noted. With the advantage of full water solubility and antiproliferative effects in tumor cell lines, the novel porphyrin compounds TMPy(3)PhenIndolprot(1)P-Cl(3) and TMPy(3)PyFluorenyl(1)P-Cl(4) could be a new therapeutic option in anticancer treatment.
Research Interests: Organic Chemistry, Water, Cytotoxicity, Porphyrins, DNA, and 16 moreCell line, In Vitro, Humans, Animals, Cell Viability, Solubility, Cattle, Water soluble polymers, Indole, Neuroendocrine Tumor, Cell Proliferation, Base Sequence, Chemical Synthesis, Antineoplastic Agents, Neuroendocrine Tumors, and Small Intestine
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The chemomechanosensory function of the gut enterochromaffin (EC) cell enables it to respond to dietary agents and mechanical stretch. We hypothesized that the EC cell, which also sensed alterations in luminal or mucosal oxygen level, was... more
The chemomechanosensory function of the gut enterochromaffin (EC) cell enables it to respond to dietary agents and mechanical stretch. We hypothesized that the EC cell, which also sensed alterations in luminal or mucosal oxygen level, was physiologically sensitive to fluctuations in O(2). Given that low oxygen levels induce 5-HT production and secretion through a hypoxia inducible factor 1α (HIF-1α)-dependent pathway, we also hypothesized that increasing O(2) would reduce 5-HT production and secretion. Isolated normal EC cells as well as the well-characterized EC cell model KRJ-I were used to examine HIF signaling (luciferase-assays), hypoxia transcriptional response element (HRE)-mediated transcription (PCR), signaling pathways (Western blot), and 5-HT release (ELISA) during exposure to different oxygen levels. Normal EC cells and KRJ-I cells express HIF-1α, and transient transfection with Renilla luciferase under HRE control identified a hypoxia-mediated pathway in these cells. PCR confirmed activation of HIF-downstream targets, GLUT1, IGF2, and VEGF under reduced O(2) levels (0.5%). Reducing O(2) also elevated 5-HT secretion (2-3.2-fold) as well as protein levels of HIF-1α (1.7-3-fold). Increasing O(2) to 100% inhibited HRE-mediated signaling, transcription, reduced 5-HT secretion, and significantly lowered HIF-1α levels (∼75% of control). NF-κB signaling was also elevated during hypoxia (1.2-1.6-fold), but no significant changes were noted in PKA/cAMP. We concluded that gut EC cells are oxygen responsive, and alterations in O(2) levels differentially activate HIF-1α and tryptophan hydroxylase 1, as well as NF-κB signaling. This results in alterations in 5-HT production and secretion and identifies that the chemomechanosensory role of EC cells extends to oxygen sensing.