We developed a xenograft model of human Chronic Eosinophilic Leukemia (CEL) to study disease progression and remission-induction under therapy with tyrosine kinase inhibitors using imatinib and nilotinib as examples. The FIP1L1/PDGFRA+ human CEL cell lineEOL-1 was injected intravenously into scid mice, and MR imaging and FACS analysis of mouse blood samples were performed to monitor disease development and the effects of imatinib and nilotinib. Organ infiltration was analyzed in detail by immunohistochemistry after sacrifice.
View Article and Find Full Text PDFThe adhesion of tumour cells to the endothelial cells of blood vessels of the microcirculation represents a crucial step in haematogenous metastasis formation. Similar to leukocyte extravasation, selectins mediate initial tumour cell rolling on endothelium. An additional mechanism of leukocyte adhesion to endothelial cells is mediated by hyaluronan (HA).
View Article and Find Full Text PDFPurpose: To establish xenograft mouse models of metastatic and nonmetastatic human prostate cancer and to apply these models to the search for aberrant glycosylation patterns associated with tumor progression in vivo and in patients.
Experimental Design: Prostate cancer cells (LNCaP, PC-3, LuCaP 23.1, and DU-145) were xenografted subcutaneously into immunodeficient pfp(-/-)/rag2(-/-) mice.
Members of the carcinoembryonic antigen cell adhesion molecules (CEACAMs) family are the prototype of tumour markers. Classically they are used as serum markers, however, CEACAMs could serve as targets for molecular imaging as well.In order to test the anti CEACAM monoclonal antibody T84.
View Article and Find Full Text PDFThe multidrug-resistance 1 (MDR-1) P-glycoprotein (Pgp) is a transmembrane transporter system, which actively pumps cytotoxic drugs out of the cell. MDR-1 acquired in vitro differs from MDR-1 acquired in vivo, but has important consequences on the cellular phenotype and metastatic behavior. Here we report that the human colonic cancer cell line HT29 (MDR-1 negative) is more malignant than its MDR-1 overexpressing variant (HT29 MDR-1 positive).
View Article and Find Full Text PDFHERG (human ether-à-go-go-related gene) K(+) currents fulfill important ionic functions in cardiac and other excitable cells. In addition, HERG channels influence cell growth and migration in various types of tumor cells. The mechanisms underlying these functions are still not resolved.
View Article and Find Full Text PDFUnlabelled: The overexpression of the chemokine receptor CXCR4 plays an important role in oncology, since together with its endogenous ligand, the stromal cell-derived factor (SDF1-α), CXCR4 is involved in tumor development, growth, and organ-specific metastasis. As part of our ongoing efforts to develop highly specific CXCR4-targeted imaging probes and with the aim to assess the suitability of this ligand for first proof-of-concept studies in humans, we further evaluated the new (68)Ga-labeled high-affinity cyclic CXCR4 ligand, (68)Ga-CPCR4-2 (cyclo(D-Tyr(1)-[NMe]-D-Orn(2)-[4-(aminomethyl) benzoic acid,(68)Ga-DOTA]-Arg(3)-2-Nal(4)-Gly(5))).
Methods: Additional biodistribution and competitions studies in vivo, dynamic PET studies, and investigations on the metabolic stability and plasma protein binding were performed in nude mice bearing metastasizing OH1 human small cell lung cancer xenografts.
Cell volume is regulated by a delicate balance between ion distribution across the plasma membrane and the osmotic properties of intra- and extracellular components. Using a fluorescent calcein indicator, we analysed the effects of glycosaminoglycans on the cell volume of hyaluronan producing fibroblasts and hyaluronan deficient HEK cells over a time period of 30 h. Exogenous glycosaminoglycans induced cell blebbing after 2 min and swelling of fibroblasts to about 110% of untreated cell volume at low concentrations which decreased at higher concentrations.
View Article and Find Full Text PDFObjective: According to Fick's law of diffusion, gas exchange depends on the size and thickness of the blood perfused alveolocapillary membrane. Impairment of either one is tenuous. No data are available concerning the impact of hydroxyethyl starches and saline on pulmonary microperfusion and gas exchange during systemic inflammation.
View Article and Find Full Text PDFThe chemokine receptor CXCR4 is a critical regulator of inflammation and immune surveillance, and it is specifically implicated in cancer metastasis and HIV-1 infection. On the basis of the observation that several of the known antagonists remarkably share a C(2) symmetry element, we constructed symmetric dimers with excellent antagonistic activity using a derivative of a cyclic pentapeptide as monomer. To optimize the binding affinity, we investigated the influence of the distance between the monomers and the pharmacophoric sites in the synthesized constructs.
View Article and Find Full Text PDFAims: The up-regulation of the cell adhesion molecule L1 has been associated with impaired prognosis in several cancers. This study aimed to identify potential prognostic markers, including L1, in adenoid cystic carcinoma of the salivary glands (ACCs), which might give additional insight into the molecular mechanisms underlying malignant progression.
Methods And Results: The expression of L1 was analysed in 34 primary ACCs (nine tubular, 15 cribriform, nine solid, one mixed) and correlated with recurrence, metastasis, overall survival and clinicopathological parameters.
Cell migration is one of the hallmarks of metastatic disease and thus identification of migration promoting proteins is crucial for the understanding of metastasis formation. Here we show that the neuron-specific, F-actin bundling inositol-1,4,5-trisphosphate-3-kinase-A (ITPKA) is ectopically expressed in tumor cells and critically involved in migration. Down-regulation of ITPKA expression in transformed cell-lines with ectopic expression of ITPKA significantly decreased migration and the number of linear and branched cell protrusion.
View Article and Find Full Text PDFPurpose: About 50% of prostate cancers have TMPRSS2-ERG fusions with concurrent ERG overexpression. The aim of this study was to determine whether clinical differences exist between ERG-positive and ERG-negative cancers in surgically treated patients not exposed to antihormonal therapy. A secondary aim was to search for differences between these tumor classes.
View Article and Find Full Text PDFBackground: Glycosylation of the tumour cell surface is of importance in metastasis formation as indicated by lectin-binding studies. In particular, binding of the lectin HPA is associated with metastasis formation, both in clinical studies and in xenograft models of breast and colon cancer. Here we examined if there is an association between the HPA-positive glycotopes of metastasizing cancer cells and selectin-binding properties.
View Article and Find Full Text PDFBackground: The purpose of this study was to assess the feasibility and accuracy of computer-assisted surgery (CAS) for screw placement in different pelvic regions using intraoperative three-dimensional (3D) imaging and to evaluate the influence of surgeons' experience with such a system on procedure time, radiation time, radiation dose, and misplacement rate.
Methods: Experimental study in a human cadaveric model (n=5) for percutaneous screw placement in the anterior column of the acetabulum, the posterior pelvic ring (S1, S2), and the superior pubic ramus via 3D fluoroscopic navigated procedure. Accuracy of screw placement was assessed by 3D image intensifier, including the reconstruction of multiplanar images and by computer tomography (CT) scan.
Pseudomonas aeruginosa (PA) can cause infections in compromised hosts by interacting with the glycocalyx of host epithelial cells. It binds to glycostructures on mucosal surfaces via two lectins, which are carbohydrate-binding proteins, named PA-IL and PA-IIL, and blocking this interaction is, thus, an attractive anti-adhesive strategy. The aim of this study was to determine by ciliary beat frequency (CBF) analysis whether monosaccharides or peptides mimicking glycostructures represent blockers of PA lectin binding to human airway cilia.
View Article and Find Full Text PDFPurpose: The intercellular adhesion molecule (ICAM)-1 is expressed on many cell types including endothelial cells and different cancer cell entities. Experimental data strongly indicate that ICAM-1 can activate intracellular signalling pathways in cancer cells leading to enhanced cell motility, invasion and metastasis. Yet, little is known about the role of ICAM-1 expression during malignant progression in breast cancer patients.
View Article and Find Full Text PDFHER-2/neu over-expression occurs in 10-40% of patients with esophageal adenocarcinoma. Therefore, inhibitory effects of trastuzumab on proliferation, neoangiogenesis and metastatic spread of the esophageal adenocarcinoma cell line PT1590 were investigated (subcutaneous xenograft model). PT1590 revealed an amplified copy number of c-erbB2 and HER-2/neu over-expression occured in xenograft tumors and spontaneous lung metastases.
View Article and Find Full Text PDFThe neural cell adhesion molecule NCAM is a cell surface glycoprotein of the immunoglobulin superfamily and is widely expressed in tumours of neuroectodermal origin such as neuroblastoma. NCAM can be decorated by the carbohydrate polymer polysialic acid (polySia), which attenuates NCAM-mediated cell adhesion and increases cellular motility. The key enzymes in the biosynthesis of polySia are the two polysialyltransferases ST8SiaII and ST8SiaIV.
View Article and Find Full Text PDFHaematogenous metastasis of small cell lung cancer (SCLC) is still a poorly understood process and represents the life threatening event in this malignancy. In particular, the rate-limiting step within the metastatic cascade is not yet clearly defined although, many findings indicate, that extravasation of circulating tumour cells is crucially important as most tumour cells within the circulation undergo apoptosis. If extravasation of SCLC tumour cells mimics leukocyte-endothelial interactions, SCLC cells should adhere to E- and P-selectins expressed on the luminal surface of activated endothelium.
View Article and Find Full Text PDFBackground: Small cell lung cancer (SCLC) is one of the most aggressive malignancies implying a very poor prognosis for patients even under therapy. Since it is known that SCLC cells exhibit neurone-like characteristics, we investigated whether a neuronal induction medium (NID) consisting of indomethacin (200 μM), 3-isobutyl-1-methylxanthine (IBMX, 500 μM) and insulin (5 μg/ml) induces neuronal differentiation and by this reduces malignancy of SCLC in vitro.
Methods: Anti-proliferative effects were tested by incubating five SCLC cell lines (OH1, OH3, SW2, H69 and H82) with NID for 72 h (XTT-assay).
Background And Aims: Parenteral nutrition is life-saving for patients with severe intestinal failure. Line-related blood stream infection is the most frequent complication and strategies have been developed to sterilize central lines. Nevertheless, failures of attempted sterilization are not well understood.
View Article and Find Full Text PDFAlthough survival rates of colon cancer patients diagnosed at an early stage (T1-2N0M0; Dukes A) vary considerably according to the studies cited, several studies indicate development of distant metastases already occurring in a considerable percentage of these patients leading to the death of the patients. This particular high risk group cannot be identified properly as no marker exists to identify these patients. As the Wnt/Win pathway plays a crucial role in metastasis formation in colorectal carcinoma, we analysed whether the transcription factor brachyury critically involved in this pathway may predict metastasis formation in these patients.
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