698 results on '"Lamers CB"'
Search Results
2. A double-blind study of pantoprazole and ranitidine in treatment of acute duodenal ulcer. A multicenter trial. European Pantoprazole Study Group
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Cremer, M, Lambert, R, Lamers, Cb, DELLE FAVE, Gianfranco, and Maier, C.
- Published
- 1995
3. Imaging features of somatostatinoma: MR, CT, US, and angiography
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Tjon A Tham Rt, Lamers Cb, Falke Th, and Jansen Jb
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Adult ,Male ,medicine.medical_specialty ,Pancreatic disease ,Neuroendocrine tumors ,Pancreatic tumor ,Somatostatinoma ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Ultrasonography ,medicine.diagnostic_test ,business.industry ,Angiography ,Middle Aged ,medicine.disease ,Primary tumor ,Magnetic Resonance Imaging ,Major duodenal papilla ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Female ,Radiology ,business ,Pancreas ,Tomography, X-Ray Computed - Abstract
OBJECTIVE The imaging features of somatostatinoma are described in four patients. MATERIALS AND METHODS Four patients, ranging in age from 24 to 57 years, with somatostatinoma were examined. Ultrasonography (US) and CT were performed in all four patients; MRI and angiography were performed in three patients. RESULTS Three patients had a tumor in the pancreas and one in the papilla major. In two cases there were metastases in the liver, and one had bone and lymph node metastases. Pancreatic tumor and metastases were equally well detected by CT and MRI. One tumor in the tail of the pancreas was initially missed by US. Pancreatic tumor and metastases were echo poor. Angiography showed one vascular and one avascular tumor in the pancreas. Chronic obstructive pancreatitis was seen on CT and MRI in the patient with the tumor in the papilla major. Angiography and US failed to demonstrate this tumor; CT and MRI showed the tumor in retrospect. Primary tumor and metastases are of low signal intensity on T1-weighted imaging and increased signal intensity on T2-weighted imaging. CONCLUSION Somatostatin-producing endocrine tumors are mainly located in the pancreas but can also be present in extrapancreatic organs such as the duodenum and papilla of Vater resulting in chronic obstructive pancreatitis. Duodenal somatostatinomas are associated with von Recklinghausen neurofibromatosis. Radiologic and MRI features of somatostatinomas resemble those of other neuroendocrine tumors. Radiological techniques and MRI often fail to demonstrate the tumors in the duodenum. The diagnosis in cases of duodenal localization can be established by endoscopic techniques.
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- 1994
4. Modulatory effects of VIP and related peptides from the gastrointestinal tract on cell mediated cytotoxicity against tumour cells in vitro
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M. N. Aparicio-Pages, Peña As, J.B.M.J. Jansen, van Tol Ea, Lamers Cb, and Verspaget Hw
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Cytotoxicity, Immunologic ,medicine.medical_specialty ,Neuroimmunomodulation ,Lymphocyte ,Immunology ,Vasoactive intestinal peptide ,CD16 ,Biology ,Natural killer cell ,Secretin ,Immune system ,Internal medicine ,medicine ,Tumor Cells, Cultured ,Humans ,Cytotoxicity ,General Medicine ,Peptide PHI ,Stimulation, Chemical ,Killer Cells, Natural ,medicine.anatomical_structure ,Endocrinology ,Gastrointestinal hormone ,Colonic Neoplasms ,Cancer research ,Leukocytes, Mononuclear ,Leukemia, Erythroblastic, Acute ,hormones, hormone substitutes, and hormone antagonists ,Vasoactive Intestinal Peptide - Abstract
In the present study the effect of vasoactive intestinal peptide (VIP), peptide histidine-methionine (PHM), and secretin on spontaneous cell mediated cytotoxicity of peripheral blood mononuclear cells against tumour target cells was evaluated. VIP stimulated cytotoxicity against CaCo-2 human colon cancer cells, whereas less effect was seen against K-562 erythroleukemia cells. Depletion of CD16+ natural killer cells almost completely abolished cytotoxicity and subsequent VIP incubation did not change residual activity. In contrast to PHM, which hardly influenced cytotoxicity, secretin was found to be more effective especially against K-562 target cells. These observations suggest a modulating role for the neuropeptide VIP in the cellular immune response against tumour cells, especially from the colon, resulting in increased activity of CD16+ natural killer cells. Secretin, seems to be less potent in modulating cellular cytotoxicity. These findings support the concept that gastrointestinal peptides can play a role in the regulation of cellular cytotoxicity against tumor cells.
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- 1991
5. Expression of receptors for gut peptides in human pancreatic adenocarcinoma and tumour-free pancreas
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Tang, C, primary, Biemond, I, additional, Offerhaus, GJA, additional, Verspaget, W, additional, and Lamers, CB, additional
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- 1997
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6. Cholecystokinin receptors in human pancreas and gallbladder muscle: A comparative study
- Author
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Tang, C, primary, Biemond, I, additional, and Lamers, CB, additional
- Published
- 1996
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7. High‐dose ranitidine for the prevention of recurrent peptic ulcer disease in rheumatoid arthritis patients taking NSAIDs.
- Author
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Ten Wolde, S, primary, Dijkmans, BA, additional, Janssen, M, additional, Hermans, J, additional, and Lamers, CB, additional
- Published
- 1996
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8. Effect of hyperglycemia on gastric acid secretion and gastrin release induced by intravenous amino acids
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Lam, WF, primary, Masclee, AA, additional, Muller, ES, additional, and Lamers, CB, additional
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- 1995
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9. Protective effect of blood transfusions on postoperative recurrence of Crohn's disease in parous women
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Silvis, R, primary, Steup, WH, additional, Brand, A, additional, Zwinderman, KA, additional, Lamers, CB, additional, Griffioen, G, additional, and Gooszen, HG, additional
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- 1994
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10. Does smoking influence the pharmacokinetics and pharmacodynamics of the H2-receptor antagonist famotidine?
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Baak, LC, primary, Ganesh, S, additional, Jansen, JB, additional, and Lamers, CB, additional
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- 1992
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11. Comparison between serology and histology in the diagnosis of advanced gastric body atrophy: a study in a Dutch primary community.
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Korstanje A, van Eeden S, Offerhaus JA, Waltman FL, Hartog G, Roelandse FW, Souverijn JH, Biemond I, and Lamers CB
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- 2008
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12. Coffee stimulation of cholecystokinin release and gallbladder contraction in humans
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Douglas, BR, primary, Jansen, JB, additional, Tham, RT, additional, and Lamers, CB, additional
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- 1990
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13. Lack of effect of the specific cholecystokinin receptor antagonist loxiglumide on cholecystokinin clearance from plasma in man.
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Jebbink, MC, primary, Jansen, JB, additional, Masclee, AA, additional, and Lamers, CB, additional
- Published
- 1990
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14. Effect of intermittent administration of omeprazole on serum pepsinogens in duodenal ulcer patients and healthy volunteers.
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Biemond, I, primary, Crobach, LF, additional, Jansen, JB, additional, and Lamers, CB, additional
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- 1990
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15. Effect of increasing oral doses of loperamide on gallbladder motility in man.
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Hopman, WP, primary, Rosenbusch, G, additional, Jansen, JB, additional, and Lamers, CB, additional
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- 1990
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16. Effect of L-arginine on lower oesophageal sphincter motility in man.
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Straathof JW, Adamse M, Onkenhout W, Lamers CB, Masclee AA, Straathof, J W, Adamse, M, Onkenhout, W, Lamers, C B, and Masclee, A A
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- 2000
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17. Nonulcer dyspepsia in a Dutch working population and Helicobacter pylori. Ulcer history as an explanation of an apparent association.
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Schlemper RJ, van der Werf SD, Vandenbroucke JP, Biemond I, and Lamers CB
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- 1995
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18. Is the measurement of blood cimetidine levels useful?
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Festen, HP, Diemel, J, Lamers, CB, Schaik, A, Tangerman, A, and Tongeren, JH
- Abstract
1 Blood cimetidine levels were measured up to 5 h after oral intake of 200 mg cimetidine with breakfast in 13 duodenal, 5 gastric and 15 anastomotic ulcer patients. 2 There were larger inter individual differences in results. The mean peak blood concentrations was 1.14 +/- 0.07 microgram/ml (range 0.54-1.94 microgram/ml), the mean period during which the blood concentration exceeded 0.5 microgram/ml was 141 +/- 11 min (range 23-306 min) and the mean area under the cimetidine blood concentration curve (AUC) was 166 +/- 8 microgram ml-1 min (range 96-280 microgram ml-1 min). Coefficient of variation of these parameters was 33%, 43% and 29% respectively. 3 There were no significant differences in these parameters between non-operated patients and patients with a partial gastrectomy. 4 In 11 patients restudied after 2 to 5 months blood cimetidine levels proved well reproducible; mean coefficient of variation of peak blood levels was 8.5 +/- 2.4%, of time during which blood levels exceeded 0.5 microgram/ml 7.6 +/- 2.5% and of the AUC 5.0 +/- 1.0%. 5 There was no difference in peak blood levels, duration of blood level exceeding 0.5 microgram/ml and blood cimetidine AUC between 24 patients healed after 4 weeks cimetidine therapy and 9 in whom healing took longer. Likewise, there was no evidence of lower blood cimetidine concentrations in 9 patients who relapsed during maintenance cimetidine treatment compared with 24 who did not relapse. [ABSTRACT FROM AUTHOR]
- Published
- 1981
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19. STARVATION IN THE RAT: EFFECT ON PEPTIDES OF THE GUT AND BRAIN.
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Shulkes, A, Caussignac, Y, Lamers, CB, Solomon, TE, Yamada, T, and Walsh, JH
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- 1983
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20. Röntgendiagnostik beim Zollinger-Ellison-Syndrom*
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C. Boetes, Lamers Cb, Snel P, G. Rosenbusch, Van Tongeren Jh, and Lubbers Ej
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endocrine system ,Pathology ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,medicine.disease ,Zollinger-Ellison syndrome ,Pathophysiology ,Muscle hypertrophy ,medicine.anatomical_structure ,Radiological weapon ,Angiography ,medicine ,Duodenum ,Radiology, Nuclear Medicine and imaging ,Gastrectomy ,business ,Pancreas - Abstract
The article discusses the y-ray diagnosis of the Zollinger-Ellison syndrome, including 13 with multiple endocrine adenomatosis, Type I. This syndrome is governed by complex pathophysiological processes determining the x-ray symptoms. Besides the predisposition to ulcers, which will persist despite partial gastrectomy, changes at the duodenum (hypertrophy of Brunner's glands) and proximal jejunum (bulging of folds) are relatively typical. However, the final diagnosis of the Zollinger-Ellison syndrome is a clinical one. The syndrome is caused by non-beta islet cell tumors of the pancreas, associated with hypergastrinemia. Since these tumors are often multiple and small, angiography is not very rewarding. It is frequently impossible to distinguish the benign from the malignant tumors on the grounds of histological findings, the only criterion being their biological behaviour, if the exclusion or identification of metastases.
- Published
- 1978
21. CT and MR Imaging of Advanced Zollinger-Ellison Syndrom
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Falke Th, Lamers Cb, Tjon A Tham Rt, and Jansen Jb
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Adult ,Male ,Zollinger-Ellison Syndrome ,Lesion ,Text mining ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Multiple endocrine neoplasia ,Lymph node ,medicine.diagnostic_test ,business.industry ,Liver Neoplasms ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Mr imaging ,Zollinger-Ellison syndrome ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Lymphatic Metastasis ,Female ,medicine.symptom ,Tomography, X-Ray Computed ,Nuclear medicine ,business ,Pancreas - Abstract
The CT and magnetic resonance (MR) findings in 13 patients with advanced Zollinger-Ellison syndrome are described. In eight patients (62%) one or more primary tumors were found with both methods. All patients with proven liver metastases (n = 7) were identified by MR. Computed tomography was positive in six of these patients. Three patients with lymph node metastases were identified on CT and MR and one patient had bone metastases. Computed tomography and MR were inferior to selective arteriography in the detection of multiple lesions of the pancreas in a patient with multiple endocrine neoplasia-I syndrome. On the T1-weighted MR images, the primary tumors demonstrated no consistency with regard to their signal intensity relative to the adjacent pancreatic parenchyma. All gastrinomas had an increased relative signal intensity on the T2-weighted images with the exception of a calcified tumor. Liver and lymph node metastases had a low signal intensity on the T1-weighted images and an increased signal intensity on the T2-weighted images. The signal intensity of primary tumors and metastases was independent of size. In conclusion, MR was able to detect abnormalities based on its outstanding lesion/normal tissue contrast, whereas CT diagnosis was based mostly on contour distortion. For the current technique, MR is considered at least equal to CT.
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- 1989
22. MR, CT, and ultrasound findings of metastatic vipoma in pancreas
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R T Tjon A Tham, F Roelfsema, Falke Th, Jansen Jb, Lamers Cb, A van den Sluys Veer, and G Griffioen
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Adult ,medicine.medical_specialty ,Adenoma ,X ray computed ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Multiple endocrine neoplasia ,VIPoma ,Ultrasonography ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Liver Neoplasms ,Multiple Endocrine Neoplasia ,Magnetic resonance imaging ,equipment and supplies ,medicine.disease ,Adenoma, Islet Cell ,Magnetic Resonance Imaging ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Female ,Radiology ,Tomography ,Vipoma ,business ,Pancreas ,Tomography, X-Ray Computed ,human activities - Abstract
Magnetic resonance, CT, and ultrasound findings are described for a vipoma of the pancreas with hepatic metastases in a patient with Verner-Morrison syndrome and multiple endocrine neoplasia I.
- Published
- 1989
23. ROLE OF SECRETIN AND CCK IN THE STIMULATION OF PANCREATIC-SECRETION IN CONSCIOUS DOGS - EFFECTS OF ATROPINE AND SOMATOSTATIN
- Author
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Konturek, Sj, Konturek, Jw, Lamers, Cb, Tasler, J., and Jan Bilski
24. PHYSIOLOGICAL-ROLE AND LOCALIZATION OF CHOLECYSTOKININ RELEASE IN DOGS
- Author
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Konturek, Sj, Tasler, J., Jan Bilski, Dejong, Aj, Jansen, Jbmj, and Lamers, Cb
25. Focal nodular hyperplasia of the liver: features on Gd-DTPA-enhanced MR
- Author
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Tham, RT, primary, Holscher, HC, additional, Falke, TH, additional, Arndt, JW, additional, and Lamers, CB, additional
- Published
- 1989
- Full Text
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26. STARVATION IN THE RAT: EFFECT ON PEPTIDES OF THE GUT AND BRAIN
- Author
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Shulkes, A, primary, Caussignac, Y, additional, Lamers, CB, additional, Solomon, TE, additional, Yamada, T, additional, and Walsh, JH, additional
- Published
- 1983
- Full Text
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27. Plasma MMP-2 and MMP-9 and their inhibitors TIMP-1 and TIMP-2 during human orthotopic liver transplantation - The effect of aprotinin and the relation to ischemia/reperfusion injury
- Author
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Bart van Hoek, Hein W. Verspaget, Marietta G Veldman, Onno T. Terpstra, Robert J. Porte, Sanne E Moolenburgh, Johan Ph. Kuyvenhoven, Cristina Legnani, Gualtiero Palareti, Cornelis B.H.W. Lamers, I. Quintus Molenaar, Rijksuniversiteit Groningen, Groningen Institute for Organ Transplantation, Kuyvenhoven JP, Molenaar IQ, Verspaget HW, Veldman MG, Palareti G, Legnani C, Moolenburgh SE, Terpstra OT, Lamers CB, van Hoek B, and Porte RJ.
- Subjects
Male ,Pathology ,Time Factors ,Plasmin ,medicine.medical_treatment ,MATRIX METALLOPROTEINASES MMP-2 ,Liver transplantation ,ischemia/reperfusion injury ,Placebos ,IMMUNOCAPTURE ASSAY ,Blood plasma ,Aprotinin ,REPERFUSION INJURY ,liver transplantation ,matrix metalloproteinases ,Hematology ,Middle Aged ,ISCHEMIA ,Matrix Metalloproteinase 9 ,Matrix Metalloproteinase 2 ,Female ,medicine.drug ,Adult ,aprotinin ,medicine.medical_specialty ,Antifibrinolytic ,Adolescent ,CARCINOMA ,medicine.drug_class ,GELATINASE ,Double-Blind Method ,Internal medicine ,medicine ,Humans ,Aspartate Aminotransferases ,PRESERVATION ,PLASMINOGEN-ACTIVATOR ,Aged ,plasmin ,Tissue Inhibitor of Metalloproteinase-2 ,Tissue Inhibitor of Metalloproteinase-1 ,business.industry ,Tumor Necrosis Factor-alpha ,medicine.disease ,Transplantation ,Endocrinology ,ACTIVATOR-ASSOCIATED FIBRINOLYSIS ,business ,Plasminogen activator ,Reperfusion injury ,SYSTEM - Abstract
SummaryUncontrolled activation of matrix metalloproteinases (MMPs) can result in tissue injury and inflammation, yet little is known about the activation of MMPs during orthotopic liver transplantation (OLT). OLT is associated with increased fibrinolytic activity due to elevated plasmin generation. The serine-protease plasmin not only causes degradation of fibrin clots but is also thought, amongst others, to play a role in the activation of some matrix metalloproteinases. We therefore studied the evolution of MMP-2 and -9 plasma concentrations during OLT and the effect of serine-protease inhibition by aprotinin on the level and activation of these MMPs. In a group of 24 patients who participated in a randomized, double-blind, placebo-controlled study we determined serial MMP-2 and MMP-9 plasma levels during transplantation using ELISA (total MMP), activity assays (activatable MMP) and zymography. In addition, the MMP-inhibitors TIMP-1 and TIMP-2 were assessed by ELISA. The putative regulating factors tumor necrosis factor alpha (TNF-α) and tissue-type plasminogen activator (t-PA) were assessed as well. Patients were administered high-dose aprotinin, regular-dose aprotinin or placebo during surgery. Plasma TIMP-1, TIMP-2 and MMP-2 level gradually decreased during transplantation. Approximately twothirds of total MMP-2 appeared to be in its activatable proMMP form. No release of MMP-2 from the graft could be detected. In contrast, plasma levels of MMP-9 increased sharply during the anhepatic and postreperfusion periods. Peak MMP-9 levels of about eight times above baseline were found at 30 minutes after reperfusion. Most MMP-9 appeared to be in its active/inhibitorcomplexed form. No significant differences were observed between the three treatment groups. However, in patients with more severe ischemia/reperfusion (I/R) injury the MMP-9 concentration, particularly of the active/inhibitor-complexed form, remained high at 120 minutes postreperfusion compared to patients with no or mild I/R injury. The decrease in plasma levels of MMP-2,TIMP-1 and TIMP-2 during OLT occurred irrespective of the severity of the I/R injury. There was a significant correlation between MMP-9 and t-PA levels, but not with TNF-α. In conclusion, OLT is associated with a sharp increase of MMP-9 during the anhepatic and postreperfusion periods, which coincided with the changes in t-PA. MMP-2, TIMP-1 and TIMP-2 gradually decreased during OLT. The composition of these MMPs was not altered by the use of aprotinin, suggesting that serine–protease/plasmin-independent pathways are responsible for MMP regulation during OLT. In addition, only MMP-9 seems to be involved in I/R injury during human liver transplantation.
- Published
- 2004
28. Expression and ligand binding of bombesin receptors in pulmonary and intestinal carcinoids.
- Author
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Kuiper P, Verspaget HW, Biemond I, de Jonge-Muller ES, van Eeden S, van Velthuysen ML, Taal BG, and Lamers CB
- Subjects
- Bombesin analogs & derivatives, Bombesin metabolism, Carcinoid Tumor pathology, Humans, Intestinal Neoplasms pathology, Ligands, Lung Neoplasms pathology, Protein Isoforms metabolism, Carcinoid Tumor metabolism, Intestinal Neoplasms metabolism, Lung Neoplasms metabolism, Receptors, Bombesin metabolism
- Abstract
Introduction: Carcinoids are mainly found in the gastrointestinal (65%) and bronchopulmonary tract (25%). These neuroendocrine tumors secrete a wide range of bioactive peptides, including gastrin releasing peptide and neuromedin B, the mammalian analogs of bombesin. The purpose of this study was to investigate the quantity and localization of bombesin receptors in gastrointestinal and pulmonary carcinoids, and to reveal whether bombesin-like peptides (BLP) and their receptors are of any value in distinguishing pulmonary carcinoids from carcinoids of intestinal origin., Methods: Carcinoid tumors with pulmonary (no.=9) or intestinal (no.=15) localizations were analyzed by immunohistochemistry, autoradiography, and radioimmunoassay, to examine the presence of bombesin receptor subtypes and determine BLP levels in these tumors., Results: All 3 bombesin receptor subtypes (GRPR, NMBR, and BRS-3) were present on pulmonary and intestinal carcinoids by immunohistochemistry. In pulmonary carcinoids, low receptor ligand binding densities together with high and low BLP levels were found. Intestinal carcinoids showed predominantly high receptor ligand binding densities in combination with low BLP levels., Conclusions: The expression of bombesin receptor subtypes is independent from the carcinoid tumor origin, and is therefore not recommended as a distinction marker, although carcinoids of pulmonary and intestinal origin possess different receptor binding affinities for bombesin and dissimilar BLP levels. The combined presence of bombesin and its receptors might suggest the presence of a paracrine or autocrine growth loop in carcinoids.
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- 2011
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29. Angiogenic markers endoglin and vascular endothelial growth factor in gastroenteropancreatic neuroendocrine tumors.
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Kuiper P, Hawinkels LJ, de Jonge-Muller ES, Biemond I, Lamers CB, and Verspaget HW
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- Adult, Aged, Carcinoid Tumor metabolism, Endoglin, Female, Humans, Immunohistochemistry methods, Male, Microcirculation, Middle Aged, Neoplasm Metastasis, Platelet Endothelial Cell Adhesion Molecule-1 biosynthesis, Vascular Endothelial Growth Factor A metabolism, Antigens, CD biosynthesis, Neuroendocrine Tumors metabolism, Pancreatic Neoplasms metabolism, Receptors, Cell Surface biosynthesis, Stomach Neoplasms metabolism, Vascular Endothelial Growth Factor A biosynthesis
- Abstract
Aim: To investigate the expression and potential prognostic role of vascular endothelial growth factor (VEGF) and endoglin in gastroenteropancreatic neuroendocrine tumors (GEP-NETs)., Methods: Microvessel density (MVD) in GEP-NETs was evaluated using endoglin and CD31 immunohistochemistry. In addition, tissue levels of endoglin and VEGF were determined in homogenates by ELISA., Results: Endoglin was highly expressed on tumor endothelial cells. CD31 MVD in GEP-NETs was significantly higher compared to endoglin MVD (P < 0.01). Two- to four-fold higher tissue levels of endoglin and VEGF were seen in tumors compared to associated normal tissue. This increased endoglin tissue expression in tumors was significantly related to tumor size (P < 0.01), presence of metastases (P = 0.04), and a more advanced tumor stage (P = 0.02), whereas expression of VEGF was not., Conclusion: We suggest that endoglin is a potential marker to indicate and predict metastases, which might be useful in the post-resection therapeutic approach of patients with GEP-NETs.
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- 2011
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30. An overview of the current diagnosis and recent developments in neuroendocrine tumours of the gastroenteropancreatic tract: the diagnostic approach.
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Kuiper P, Verspaget HW, Overbeek LI, Biemond I, and Lamers CB
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- Gastrointestinal Neoplasms epidemiology, Humans, Incidence, Netherlands epidemiology, Neuroendocrine Tumors epidemiology, Pancreatic Neoplasms epidemiology, Rare Diseases diagnosis, Rare Diseases epidemiology, Gastrointestinal Neoplasms diagnosis, Neuroendocrine Tumors diagnosis, Pancreatic Neoplasms diagnosis
- Abstract
Neuroendocrine tumours of the gastroenteropancreatic tract (GEP-NETs) comprise a group of very heterogeneous neoplasms, which are considered 'rare diseases'. Epidemiological studies on the incidence of GEP-NETs worldwide have reported a remarkable increase in the detection of these tumours. In a recent study, based on pathology reports (PALGA) to investigate the incidence of pancreatic and duodenal neuroendocrine tumours in the Netherlands from 1991 until 2009, we also noticed a significant increase in the incidence of these tumours. In particular, the incidence of non-functioning neuroendocrine tumours had significantly increased over this period. Remarkably, a substantial discrepancy was observed between the numbers of neuroendocrine tumours diagnosed in the clinical as opposed to the pathological setting, emphasising that these tumours provide a real diagnostic challenge. To improve the diagnosis of GEP -NET s, we advocate that these complex neoplasms should receive more specialised attention. In this mini-review we provide an overview of the current diagnostic approach to GEP-NETs, and add the recent developments in establishing the diagnosis of these tumours, in order to increase knowledge and awareness of GEP-NETs among clinicians and pathologists. Early detection in order to prevent morbidity from GEP-NETs is advocated.
- Published
- 2011
31. Pathological incidence of duodenopancreatic neuroendocrine tumors in the Netherlands: a Pathologisch Anatomisch Landelijk Geautomatiseerd Archief study.
- Author
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Kuiper P, Verspaget HW, van Slooten HJ, Overbeek L, Biemond I, and Lamers CB
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- Adolescent, Adult, Age Distribution, Age Factors, Aged, Aged, 80 and over, Child, Child, Preschool, Duodenal Neoplasms epidemiology, Female, Humans, Incidence, Infant, Infant, Newborn, Male, Middle Aged, Netherlands epidemiology, Neuroendocrine Tumors epidemiology, Pancreatic Neoplasms epidemiology, Registries statistics & numerical data, Young Adult, Duodenal Neoplasms pathology, Neuroendocrine Tumors pathology, Pancreatic Neoplasms pathology
- Abstract
Objectives: Duodenopancreatic neuroendocrine tumors are rare, although current epidemiological studies worldwide suggest an incidence rate increase. We assessed the pathological incidence of duodenopancreatic neuroendocrine tumors for 18 years in The Netherlands., Methods: Standardized excerpts from pathological reports of all patients who had a diagnosis of duodenopancreatic neuroendocrine tumors from 1991 until 2009 were collected from the Pathologisch Anatomisch Landelijk Geautomatiseerd Archief and reviewed. This nationwide network and registry of histopathological and cytopathological data covers 100% of the pathological reports in The Netherlands., Results: We identified 905 patients with pancreatic (n = 692) or duodenal (n = 213) neuroendocrine tumors. Most of these patients (69.4%) had a nonfunctional tumor. Functional tumors were diagnosed at a younger age compared with nonfunctional tumors (mean [SD] age, 52.3 [17.7] years vs 60.0 [14.6] years, respectively; P < 0.0001). The mean annual incidence rates per 1,000,000 persons over 1991 to 2009 were 2.54 for pancreatic and 0.81 for duodenal neuroendocrine tumors. The highest incidence was found in patients 65 to 79 years of age. The incidence of nonfunctional neuroendocrine tumors had increased significantly for 2 decades (P < 0.0001)., Conclusions: The incidence of duodenopancreatic nonfunctional neuroendocrine tumors in The Netherlands increased over 1991 to 2009. The etiology for this change includes improved diagnostic techniques and clinical awareness, as discussed.
- Published
- 2010
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32. 5-aminosalicylic acid interferes in the cell cycle of colorectal cancer cells and induces cell death modes.
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Koelink PJ, Mieremet-Ooms MA, Corver WE, Wolanin K, Hommes DW, Lamers CB, and Verspaget HW
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- Caco-2 Cells, Cell Division drug effects, Flow Cytometry, G2 Phase drug effects, HCT116 Cells, HT29 Cells, Humans, Inhibitor of Apoptosis Proteins, Microtubule-Associated Proteins metabolism, Mitosis drug effects, PPAR gamma metabolism, S Phase drug effects, Spindle Apparatus drug effects, Spindle Apparatus pathology, Survivin, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Apoptosis drug effects, Colorectal Neoplasms drug therapy, Colorectal Neoplasms pathology, Mesalamine pharmacology
- Abstract
Introduction: Epidemiological data suggests that 5-aminosalicylic acid (5-ASA), a nonsteroidal antiinflammatory drug used in the treatment of inflammatory bowel diseases, prevents colorectal cancer development in these patients, although the mechanisms remain incompletely understood., Methods and Results: Here we report that 5-ASA prevents growth of several colorectal cancer cell lines by interfering in the cell cycle, i.e., an S-phase and G2/M phase arrest, dependent on 5-ASA dosage and concentration, together with an increased mitotic index. In addition, prolonged cell cycle arrest by repeated 5-ASA treatment induced apoptosis and caused abnormal spindle organization leading to mitotic catastrophe, another form of cell death., Conclusion: These observations illustrate that 5-ASA has chemopreventive and chemotherapeutic properties.
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- 2010
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33. Diagnostic efficacy of the secretin stimulation test for the Zollinger-Ellison syndrome: an intra-individual comparison using different dosages in patients and controls.
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Kuiper P, Biemond I, Masclee AA, Jansen JB, Verspaget HW, and Lamers CB
- Subjects
- Fasting, Female, Humans, Male, Middle Aged, Sensitivity and Specificity, Gastrins blood, Secretin, Zollinger-Ellison Syndrome diagnosis
- Abstract
Background/aims: The secretin stimulation test is the principal diagnostic tool to identify Zollinger-Ellison syndrome (ZES). We investigated, by intra-individual comparison, which dose of secretin results in the highest diagnostic efficacy to identify the ZES., Methods: Fifty-seven paired secretin stimulation tests, using both 0.26 microg/kg and 0.78 microg/kg secretin, performed in 13 ZES patients and 12 controls, were analyzed and the findings confirmed in a validation cohort., Results: A gastrin increase of >100 ng/l was found to be the most sensitive and specific criterion for a positive test. Higher gastrin increases after 0.78 microg/kg compared to 0.26 microg/kg secretin contributed to a slightly more sensitive (82.9 vs. 80.5%) but less specific (68.8 vs. 81.3%) test. A validation cohort, with 98 tests using 0.26 microg/kg secretin in 21 ZES patients and 39 controls, provided similar results. In ZES patients with normal fasting serum gastrin levels (<100 ng/l), there was no diagnostic benefit from the use of a higher secretin dose., Conclusions: The 0.26 microg/kg secretin stimulation test has the best diagnostic efficacy for the ZES. and IAP.
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- 2010
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34. 5-Aminosalicylic acid inhibits TGF-beta1 signalling in colorectal cancer cells.
- Author
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Koelink PJ, Hawinkels LJ, Wiercinska E, Sier CF, ten Dijke P, Lamers CB, Hommes DW, and Verspaget HW
- Subjects
- Active Transport, Cell Nucleus drug effects, Cell Line, Tumor, Colorectal Neoplasms metabolism, Colorectal Neoplasms pathology, Humans, Phosphorylation, Smad3 Protein metabolism, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Colorectal Neoplasms drug therapy, Mesalamine pharmacology, Signal Transduction drug effects, Transforming Growth Factor beta1 antagonists & inhibitors
- Abstract
The transforming growth factor-beta (TGF-beta) pathway is an important pathway in the initiation and progression of colorectal cancer. We aimed to determine the effects of 5-aminosalicylic acid (5-ASA) on TGF-beta signalling in colorectal cancer cells in vitro. 5-ASA inhibited TGF-beta1 signalling in HCT116 cells and colonic fibroblasts, as judged by a TGF-beta-specific reporter gene assay, plasminogen activator inhibitor-1 mRNA and protein levels, fibroblast trans-differentiation, Smad3 phosphorylation and nuclear translocation. We conclude that 5-ASA inhibits TGF-beta1 signalling in colorectal cancer cells, and might be a potent adjuvant therapeutic drug, interfering with aberrant TGF-beta signalling in colorectal cancer., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)
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- 2010
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35. Clinical significance of stromal apoptosis in colorectal cancer.
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Koelink PJ, Sier CF, Hommes DW, Lamers CB, and Verspaget HW
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- Adult, Aged, Aged, 80 and over, Antigens, Neoplasm metabolism, Caspase 3 metabolism, Colorectal Neoplasms enzymology, Colorectal Neoplasms metabolism, Disease-Free Survival, Epithelial Cells enzymology, Epithelial Cells metabolism, Epithelial Cells pathology, Female, Follow-Up Studies, Gastric Mucosa enzymology, Gastric Mucosa metabolism, Humans, Immunohistochemistry, Keratins metabolism, Male, Middle Aged, Neoplasm Recurrence, Local, Prognosis, Reproducibility of Results, Stromal Cells enzymology, Stromal Cells metabolism, Time Factors, Apoptosis, Colorectal Neoplasms diagnosis, Colorectal Neoplasms pathology, Stromal Cells pathology
- Abstract
Background: Epithelial and stromal cells play an important role in the development of colorectal cancer (CRC). We aimed to determine the prognostic significance of both epithelial and stromal cell apoptosis in CRC., Methods: Total apoptosis was determined by caspase-3 activity measurements in protein homogenates of CRC specimens and adjacent normal mucosa of 211 CRC patients. Epithelial apoptosis was determined by an ELISA specific for a caspase-3-degraded cytokeratin 18 product, the M30 antigen. Stromal apoptosis was determined from the ratio between total and epithelial apoptosis., Results: Epithelial and stromal apoptosis, as well as total apoptosis, were significantly higher in CRC compared with corresponding adjacent normal mucosa. Low total tumour apoptosis (< or = median caspase-3 activity) was associated with a significantly worse disease recurrence (hazard ratio (HR), 95% confidence interval (95% CI): 1.77 (1.05-3.01)), independent of clinocopathological parameters. Epithelial apoptosis was not associated with clinical outcome. In contrast, low stromal apoptosis (< or = median caspase-3/M30) was found to be an independent prognostic factor for overall survival, disease-free survival and disease recurrence, with HRs (95% CI) of 1.66 (1.17-2.35), 1.62 (1.15-2.29) and 1.69 (1.01-2.85), respectively., Interpretation: Stromal apoptosis, in contrast to epithelial apoptosis, is an important factor with respect to survival and disease-recurrence in CRC.
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- 2009
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36. 5-Aminosalicylic acid inhibits colitis-associated but not sporadic colorectal neoplasia in a novel conditional Apc mouse model.
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Koelink PJ, Robanus-Maandag EC, Devilee P, Hommes DW, Lamers CB, and Verspaget HW
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- Aminosalicylic Acids therapeutic use, Animals, Anticarcinogenic Agents therapeutic use, Cell Proliferation drug effects, Colitis chemically induced, Colorectal Neoplasms etiology, Colorectal Neoplasms pathology, Dextran Sulfate, Disease Models, Animal, Female, Male, Mice, Aminosalicylic Acids pharmacology, Anticarcinogenic Agents pharmacology, Colitis complications, Colorectal Neoplasms prevention & control, Genes, APC physiology
- Abstract
Genetic predisposition, life-style habits and inflammatory bowel diseases (IBD)-related colitis are a main risk factor for colorectal cancer (CRC). 5-Aminosalicylic acid (5-ASA, mesalazine) is a mainstay therapy in IBD and believed to reduce the risk for developing CRC. We aimed to determine the ability of 5-ASA enemas to inhibit the development of sporadic and colitis-related neoplasia in mice. FabplCre;Apc(15lox/+) mice, which spontaneously develop sporadic colorectal tumours, were treated at 5 weeks of age with 5-ASA or placebo enemas for 3 weeks and examined for colorectal tumourigenesis at 8 weeks of age. Colitis-related tumour development was investigated in these mice by administration of dextran sodium sulphate, inducing intestinal inflammation and accelerating colorectal tumourigenesis, combined with treatment of 5-ASA or placebo enemas during and/or after colitis induction. 5-ASA significantly reduced colitis-accelerated neoplasia development by 50%, from 19.4 +/- 2.7 to 9.4 +/- 2.4 (mean tumour numbers +/- SEM, P = 0.02), in the distal part of the large intestine covered by the enema. 5-ASA was only effective when given during and/or after the intestinal inflammatory period. 5-ASA did not reduce, however, sporadic neoplasia development in the FabplCre;Apc(15lox/+) mice. 5-ASA tended to reduce proliferation of epithelial cells in the colitis-associated colorectal tumours but not in the sporadic colorectal tumours. In conclusion, 5-ASA medication inhibits the development of colitis-associated tumours in FabplCre;Apc(15lox/+) mice when administered during and/or after the induction of inflammation. 5-ASA does not reduce, however, sporadic tumour development in this mouse model.
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- 2009
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37. Active TGF-beta1 correlates with myofibroblasts and malignancy in the colorectal adenoma-carcinoma sequence.
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Hawinkels LJ, Verspaget HW, van der Reijden JJ, van der Zon JM, Verheijen JH, Hommes DW, Lamers CB, and Sier CF
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- Actins metabolism, Adenoma pathology, Biomarkers, Tumor metabolism, Carcinoma pathology, Colorectal Neoplasms pathology, Desmin metabolism, Enzyme-Linked Immunosorbent Assay, Female, Fibroblasts pathology, HT29 Cells, Humans, Immunohistochemistry, Keratins metabolism, Male, Muscle, Smooth pathology, Plasminogen Activator Inhibitor 1 metabolism, Reproducibility of Results, Sensitivity and Specificity, Smad2 Protein metabolism, Urokinase-Type Plasminogen Activator metabolism, Vimentin metabolism, Adenoma metabolism, Carcinoma metabolism, Colorectal Neoplasms metabolism, Fibroblasts metabolism, Muscle, Smooth metabolism, Transforming Growth Factor beta1 metabolism
- Abstract
Transforming growth factor-beta1 (TGF-beta1), a cytokine involved in various stages of cancer, is produced as a latent complex and requires processing to become active. We have determined total and active TGF-beta1 levels in homogenates of colorectal neoplasia. In contrast to total TGF-b levels, showing a stepwise increase in the mucosa-adenoma-carcinoma sequence, active TGF-beta1 levels are increased only in carcinomas but not in premalignant adenomas. Furthermore, solely active TGF-beta1 levels are associated with the stage of the carcinomas and worse patient prognosis. Active TGF-beta1 levels correlated significantly with plasminogen activator inhibitor (PAI)-1, alpha-smooth muscle actin (SMA) and several matrix-remodeling proteinases. Interestingly, SMA levels are also significantly increased in colorectal carcinomas but not in adenomas, suggesting that despite the enhanced total TGF-beta1 levels, myofibroblast accumulation is not (yet) occurring in these premalignant neoplasias. The correlation between active TGF-beta1 and SMA expression in tumors indicates that tumor-promoting myofibroblasts might arise as a result of increased TGF-beta1 activation. These data underline the significance of the interaction between malignant cells and (myo)-fibroblasts in the tumor microenvironment, modulating the biologic behavior of colorectal cancer.
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- 2009
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38. Circulating cell death products predict clinical outcome of colorectal cancer patients.
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Koelink PJ, Lamers CB, Hommes DW, and Verspaget HW
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- Adult, Aged, Aged, 80 and over, Caspases metabolism, Colorectal Neoplasms pathology, Enzyme-Linked Immunosorbent Assay statistics & numerical data, Female, Humans, Kaplan-Meier Estimate, Keratin-18 metabolism, Male, Middle Aged, Multivariate Analysis, Predictive Value of Tests, Prognosis, Proportional Hazards Models, Time Factors, Colorectal Neoplasms blood, Colorectal Neoplasms surgery, Keratin-18 blood
- Abstract
Background: Tumor cell death generates products that can be measured in the circulation of cancer patients. CK18-Asp396 (M30 antigen) is a caspase-degraded product of cytokeratin 18 (CK18), produced by apoptotic epithelial cells, and is elevated in breast and lung cancer patients., Methods: We determined the CK18-Asp396 and total CK18 levels in plasma of 49 colorectal cancer patients, before and after surgical resection of the tumor, by ELISA. Correlations with patient and tumor characteristics were determined by Kruskal-Wallis H and Mann-Whitney U tests. Disease-free survival was determined using Kaplan-Meier methodology with Log Rank tests, and univariate and multivariate Cox proportional hazard analysis., Results: Plasma CK18-Asp396 and total CK18 levels in colorectal cancer patients were related to disease stage and tumor diameter, and were predictive of disease-free survival, independent of disease-stage, with hazard ratios (HR) of patients with high levels (> median) compared to those with low levels (< or = median) of 3.58 (95% CI: 1.17-11.02) and 3.58 (95% CI: 0.97-7.71), respectively. The CK18-Asp396/CK18 ratio, which decreased with tumor progression, was also predictive of disease-free survival, with a low ratio (< or = median) associated with worse disease-free survival: HR 2.78 (95% CI: 1.06-7.19). Remarkably, the plasma CK18-Asp396 and total CK18 levels after surgical removal of the tumor were also predictive of disease-free survival, with patients with high levels having a HR of 3.78 (95% CI: 0.77-18.50) and 4.12 (95% CI: 0.84-20.34), respectively, indicating that these parameters can be used also to monitor patients after surgery., Conclusion: CK18-Asp396 and total CK18 levels in the circulation of colorectal cancer patients are predictive of tumor progression and prognosis and might be helpful for treatment selection and monitoring of these patients.
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- 2009
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39. Matrix metalloproteinases and their tissue inhibitors as prognostic indicators for diagnostic and surgical recurrence in Crohn's disease.
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Meijer MJ, Mieremet-Ooms MA, Sier CF, van Hogezand RA, Lamers CB, Hommes DW, and Verspaget HW
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- Adolescent, Alleles, Crohn Disease diagnosis, Crohn Disease surgery, Enzyme-Linked Immunosorbent Assay, Female, Genotype, Humans, Male, Medical Records, Prognosis, Prospective Studies, Recurrence, Retrospective Studies, Tissue Inhibitor of Metalloproteinase-1 metabolism, Tissue Inhibitor of Metalloproteinase-2 metabolism, Tumor Necrosis Factor-alpha genetics, Tumor Necrosis Factor-alpha metabolism, Young Adult, Crohn Disease genetics, Matrix Metalloproteinase 9 genetics, Polymorphism, Single Nucleotide genetics, Tissue Inhibitor of Metalloproteinase-1 genetics, Tissue Inhibitor of Metalloproteinase-2 genetics
- Abstract
Background: Recurrence of disease after surgically induced remission constitutes a major and largely unpredictable problem in Crohn's disease (CD). Matrix metalloproteinases (MMP) and the tissue inhibitors of metalloproteinases (TIMP) are involved in the (etio)pathogenesis of CD and may thereby also affect postsurgical outcome. We studied the predictive value of 1) allelic composition at MMP, TIMP, and TNF-alpha single nucleotide polymorphism loci, and 2) MMP and TIMP intestinal protein levels relative to important clinical variables for recurrence of CD after resection of diseased bowel., Methods: From 87 CD patients with a full medical record, surgically resected tissue was homogenized and analyzed for single nucleotide polymorphism (SNP) genotype and MMP-TIMP protein levels. The prognostic value of these parameters was determined using the uni- and multivariate Cox proportional hazards analyses., Results: The T allele at TIMP-1 SNP +372 T/C was found to be associated with an increased risk for surgical recurrence. Higher levels of TIMP-1, TIMP-2, and MMP-9 in noninflamed CD tissue, but not in inflamed tissue, and negative smoking status independently protected against diagnostic and/or surgical recurrence., Conclusions: The TIMP-1 SNP +372 T allele with an increased risk of recurrence is in line with our previous results demonstrating increased CD susceptibility and low TIMP-1 protein expression associated with this allele. High TIMP and MMP-9 levels in noninflamed tissue are predictive of a favorable disease recurrence in CD. The contribution of MMP-9 and TIMPs to disease recurrence appears not to be mediated by smoking status, since no correlation with this parameter could be demonstrated.
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- 2009
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40. VEGF release by MMP-9 mediated heparan sulphate cleavage induces colorectal cancer angiogenesis.
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Hawinkels LJ, Zuidwijk K, Verspaget HW, de Jonge-Muller ES, van Duijn W, Ferreira V, Fontijn RD, David G, Hommes DW, Lamers CB, and Sier CF
- Subjects
- Angiogenesis Inhibitors pharmacology, Antibodies, Monoclonal pharmacology, Antibodies, Monoclonal, Humanized, Bevacizumab, Cell Hypoxia physiology, Enzyme-Linked Immunosorbent Assay, Extracellular Matrix metabolism, HT29 Cells, Humans, Matrix Metalloproteinase 2 metabolism, Matrix Metalloproteinase 9 pharmacology, Neutrophils metabolism, Spheroids, Cellular, Vascular Endothelial Growth Factor A antagonists & inhibitors, Colorectal Neoplasms blood supply, Heparitin Sulfate metabolism, Matrix Metalloproteinase 9 physiology, Neovascularization, Pathologic metabolism, Vascular Endothelial Growth Factor A metabolism
- Abstract
Angiogenesis is crucial for the progression of colorectal carcinomas in which the bioavailability of Vascular Endothelial Growth Factor (VEGF) plays a major role. VEGF bioavailability is regulated by proteolytic release or cleavage. In colorectal cancer patients, we observed a significant correlation between circulating VEGF and tumour tissue Matrix Metalloproteinase-9 (MMP-9) levels but not with MMP-2. Therefore, we evaluated the role of MMP-9 in regulating VEGF bioavailability and subsequent angiogenesis in 3-dimensional human cell culture models. MMP-9 treatment released VEGF dose-dependently from HT29 colon carcinoma spheroids, comparable to heparitinase, a known mediator of VEGF release. Conditioned medium from human neutrophils, containing high amounts of active MMP-9, released VEGF comparable to recombinant MMP-9, in contrast to myofibroblast medium. MMP-9 treated spheroids showed decreased extracellular levels of heparan sulphates, required for VEGF binding to the matrix, whereas the levels in the medium were increased. Western blot analysis revealed that VEGF(165) is the major isoform released by MMP-9 treatment. In vitro experiments indicated that MMP-9 is not capable to cleave VEGF(165) into smaller isoforms, like plasmin does. These data suggested that MMP-9 mediates release rather than the cleavage of larger VEGF isoforms. Medium from MMP-9 treated HT29 spheroids induced endothelial cell sprouting in an angiogenesis assay, comparable to the effect of recombinant VEGF(165). Anti-VEGF antibody treatment resulted in a strongly reduced number of sprouts. In conclusion, we have shown that neutrophil-derived MMP-9 is able to release biologically active VEGF(165) from the ECM of colon cancer cells by the cleavage of heparan sulphates.
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- 2008
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41. Flexible limited sampling model for monitoring tacrolimus in stable patients having undergone liver transplantation with samples 4 to 6 hours after dosing is superior to trough concentration.
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Langers P, Press RR, den Hartigh J, Cremers SC, Baranski AG, Lamers CB, Hommes DW, and van Hoek B
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- Adult, Aged, Area Under Curve, Female, Humans, Immunosuppressive Agents blood, Immunosuppressive Agents therapeutic use, Male, Middle Aged, Models, Statistical, Population, Regression Analysis, Sampling Studies, Tacrolimus blood, Tacrolimus therapeutic use, Young Adult, Immunosuppressive Agents pharmacokinetics, Liver Transplantation immunology, Tacrolimus pharmacokinetics
- Abstract
Trough (C0) monitoring is not optimal for therapeutic drug monitoring of tacrolimus. To better estimate systemic exposure of tacrolimus and achieve clinical benefit, an improved therapeutic drug monitoring strategy should be developed. The authors examined which single and combination of time points best estimated the empiric "gold standard" AUC0-12h and developed and validated a new, flexible, and accurate limited sampling model for monitoring tacrolimus in patients having undergone liver transplantation. Twenty-three stable patients with full AUC0-12h were divided into two groups based on area under the concentration-time curve/dose. With multiple regression analysis, limited sampling formulae were derived and population-pharmacokinetic-based limited sampling models were developed and validated. A regression analysis was performed between either area under the concentration-time curves calculated with formulae or models with the reference trapezoidal AUC0-12h. Both formulae and models based on single samples C4-C6 (r2 = 0.94 [MPE/MAPE 0/7]-0.90 [2/8] and 0.97 [0/7]-0.97 [1/5]) showed excellent performance. The calculated area under the concentration-time curve target range for tacrolimus was 90 to 130 h*microg/L. Multiple point sampling performed better, especially when using models (r2 > 0.94). C0 was a less precise predictor of AUC0-12h compared with both formulae and models (r2's 0.68 [5/17] and 0.87 [2/14]). In conclusion, trough concentration monitoring is not an accurate method for assessing systemic exposure to tacrolimus in stable patients having undergone liver transplantation. This new limited sampling model, based on single time points C4-C6, shows excellent performance in estimating the AUC0-12h.
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- 2008
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42. MMP-2 geno-phenotype is prognostic for colorectal cancer survival, whereas MMP-9 is not.
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Langers AM, Sier CF, Hawinkels LJ, Kubben FJ, van Duijn W, van der Reijden JJ, Lamers CB, Hommes DW, and Verspaget HW
- Subjects
- Colorectal Neoplasms mortality, Genotype, Humans, Phenotype, Prognosis, Promoter Regions, Genetic, Colorectal Neoplasms enzymology, Matrix Metalloproteinase 2 genetics, Matrix Metalloproteinase 9 genetics, Polymorphism, Single Nucleotide
- Abstract
The prognostic significance of single-nucleotide polymorphisms (SNPs) and tumour protein levels of MMP-2 and MMP-9 was evaluated in 215 colorectal cancer patients. Single-nucleotide polymorphism MMP-2(-1306T) and high MMP-2 levels were significantly associated with worse survival. Extreme tumour MMP-9 levels were associated with poor prognosis but SNP MMP-9(-1562C>T) was not. Tumour MMP levels were not determined by their SNP genotypes.
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- 2008
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43. Gluten tolerance in adult patients with celiac disease 20 years after diagnosis?
- Author
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Hopman EG, von Blomberg ME, Batstra MR, Morreau H, Dekker FW, Koning F, Lamers CB, and Mearin ML
- Subjects
- Adult, Aged, Aged, 80 and over, Autoantibodies blood, Bone Density, Celiac Disease genetics, Celiac Disease immunology, Celiac Disease pathology, Female, Follow-Up Studies, Glutens administration & dosage, Glutens immunology, HLA-DQ Antigens blood, Histocompatibility Testing, Humans, Immune Tolerance, Intestinal Mucosa pathology, Intestine, Small pathology, Male, Middle Aged, Patient Compliance, Severity of Illness Index, Celiac Disease diet therapy, Glutens adverse effects
- Abstract
Background and Objective: Celiac disease (CD) is believed to be a permanent intolerance to gluten. A number of patients, however, discontinue the gluten-free diet (GFD) without developing symptoms or signs. The aim of our study was to investigate whether CD patients are capable of developing tolerance to gluten., Methods: All 77 adult patients from our hospital known to have biopsy-proven CD for more than 10 years were invited to participate. We investigated symptoms, gluten consumption, antibodies for CD and other autoimmunity, human leukocyte antigen (HLA)-typing, bone mineral density, and performed small bowel biopsies. Tolerance was defined as no immunological or histological signs of CD while consuming gluten., Results: Sixty-six patients accepted participation, but after review of the diagnostic biopsies 53 were found to have true CD. Twenty-three percent of patients had a gluten-containing diet, 15% admitted gluten transgression and 62% followed the GFD. Patients on a GFD had significantly more osteoporosis. Normal small bowel mucosa was found in four of eight on gluten-containing diet and in four of four with gluten transgression. Two patients were considered to have developed tolerance to gluten. One of them was HLA-DQ2/DQ8 negative., Conclusion: Development of tolerance to gluten seems possible in some patients with CD. Further follow-up will show whether this tolerance is permanent or only a long-term return to latency. This feature may be associated with genetic characteristics, especially with HLA genotypes that differ from DQ2 or DQ8. More insight into the mechanisms of the development of gluten tolerance may help to distinguish those CD patients that might not require life-long GFD.
- Published
- 2008
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44. Motilin receptor expression in smooth muscle, myenteric plexus, and mucosa of human inflamed and noninflamed intestine.
- Author
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Ter Beek WP, Muller ES, van den Berg M, Meijer MJ, Biemond I, and Lamers CB
- Subjects
- Adolescent, Adult, Aged, Autoradiography, Colon metabolism, Colon pathology, Female, Humans, Ileum metabolism, Ileum pathology, Immunohistochemistry, Inflammatory Bowel Diseases genetics, Inflammatory Bowel Diseases pathology, Intestinal Mucosa pathology, Male, Middle Aged, Peroxidase metabolism, RNA, Messenger biosynthesis, Receptors, Gastrointestinal Hormone biosynthesis, Receptors, Neuropeptide biosynthesis, Reverse Transcriptase Polymerase Chain Reaction, Gene Expression genetics, Inflammatory Bowel Diseases metabolism, Intestinal Mucosa metabolism, Muscle, Smooth metabolism, RNA, Messenger genetics, Receptors, Gastrointestinal Hormone genetics, Receptors, Neuropeptide genetics
- Abstract
Background: Besides regulation of upper gastrointestinal motility, motilin seems to play a role in the inflammatory response. Motilin receptor expression in human intestine has not been studied thoroughly. This study aimed to describe the intestinal distribution of motilin receptors in inflammatory bowel disease (IBD) and control patients., Methods: Quantitative autoradiography, immunohistochemistry, and reverse-transcriptase polymerase chain reaction (RT-PCR) were used to detect motilin receptors in tissue of 25 IBD patients (13 Crohn's disease [CD], 12 ulcerative colitis [UC]) and 19 patients with a neoplasm (controls)., Results: Median muscular motilin binding was 3 and 8 fmol/g tissue in colon and ileum, respectively. In the gastroduodenal region the median was higher (93 fmol/g). In UC colonic muscular motilin binding was significantly increased compared to controls (7 vs. 3 fmol/g, P < or = 0.05). Expression in CD was similar to controls. Besides the binding found in the muscular compartment, motilin binding was also found in the mucosa, which was even higher than in the muscle (3 versus 11 and 8 versus 27 fmol/g for colon and ileum (P < or = 0.06), respectively). RT-PCR and immunohistochemistry confirmed the mucosal motilin receptor expression. The mucosal motilin receptors were located in the epithelial cells. In the muscular compartment receptors were strongly present in the myenteric plexus and weakly in the smooth muscle cells. In IBD tissue the expression pattern was not different., Conclusions: The motilin receptor is expressed in human colonic and ileal smooth muscle. Further, motilin receptor expression was also shown in the mucosa. Muscular binding in UC patients is increased but no different expression pattern was found.
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- 2008
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45. Individualized population pharmacokinetic model with limited sampling for cyclosporine monitoring after liver transplantation in clinical practice.
- Author
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Langers P, Cremers SC, den Hartigh J, Rijnbeek EM, Ringers J, Lamers CB, Hommes DW, and van Hoek B
- Subjects
- Adult, Aged, Area Under Curve, Bayes Theorem, Cyclosporine administration & dosage, Dose-Response Relationship, Drug, Female, Graft Rejection prevention & control, Humans, Immunosuppressive Agents administration & dosage, Male, Middle Aged, Models, Chemical, Regression Analysis, Sensitivity and Specificity, Cyclosporine pharmacokinetics, Immunosuppressive Agents pharmacokinetics, Liver Transplantation rehabilitation
- Abstract
Background: We recently developed and validated limited sampling models (LSMs) for cyclosporine monitoring after orthotopic liver transplantation based on individualized population pharmacokinetic models with Bayesian modelling. Aim To evaluate LSM in practice, and to seek optimal balance between benefit and discomfort., Methods: In 30 stable patients, more than 6 months after orthotopic liver transplantation, previously switched from trough- to 2 h post-dose (C2)-monitoring, we switched to 3-monthly LSM 0,1,2,3 h-monitoring. During 18 months we evaluated dose, creatinine clearance, calculated area under the curve, intra-patient pharmacokinetic variability and ability to assess systemic exposure by several previously validated LSMs., Results: Within patients, there was variability of cyclosporine-area under the curve with the same dose (CV of 15%). Compared to C2-monitoring, there was no significant difference in dose (P = 0.237), creatinine clearance (P = 0.071) and number of rejections. Some models showed excellent correlation and precision with LSM 0,1,2,3 h comparing area under the curves (0,2 h: r(2) = 0.88; 0,1,3 h: r(2) = 0.91; 0,2,3 h: r(2) = 0.92, all P < 0.001) with no difference in advised dose., Conclusions: The limited sampling model, with only trough- and 2-h sampling, yields excellent accuracy and assesses systemic exposure much better than C2 with less bias and greater precision. Considering the calculated intra-patient variability, more precision is redundant, so LSM 0,2 h seems the optimal way of cyclosporine-monitoring.
- Published
- 2007
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46. Substance P receptor expression in patients with inflammatory bowel disease. Determination by three different techniques, i.e., storage phosphor autoradiography, RT-PCR and immunohistochemistry.
- Author
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ter Beek WP, Biemond I, Muller ES, van den Berg M, and Lamers CB
- Subjects
- Adult, Aged, Autoradiography, Colon pathology, DNA Primers, Female, Humans, Ileum pathology, Immunohistochemistry, Inflammatory Bowel Diseases pathology, Male, Middle Aged, RNA, Messenger genetics, Reference Values, Reverse Transcriptase Polymerase Chain Reaction, Inflammatory Bowel Diseases genetics, Receptors, Neurokinin-1 genetics
- Abstract
Inflammatory bowel disease (IBD) is characterized by chronic intestinal inflammation accompanied by changes in motility. It is known that regulatory peptides like substance P (SP) are important pro-inflammatory peptides which are also involved in neuronal conduction. To get clues for new diagnostic and therapeutic approaches we describe the SP receptor (NK-1) distribution in IBD compared to control intestinal tissue, on mRNA and protein level by three complementary techniques. Autoradiography showed differences within the intestinal wall of control patients; mucosal binding was 17 fmol/g and muscular binding was significantly (p=0.01) higher (98 fmol/g). In inflamed specimens of patients with IBD mucosal SP binding was increased compared to controls (55+/-10 vs 18+/-4 fmol/g mucosa, p=0.002). However RT-PCR showed that the mRNA content of the NK-1 receptor in these samples was not increased. In non-inflamed samples of patients with Crohn's disease (CD) and ulcerative colitis (UC) SP binding was similar as in controls, while mRNA was significantly decreased in CD patients (0.7+/-0.02 vs 4.4+/-0.7, p=0.01) but not in UC patients (4.4+/-0.7 vs 4.1+/-1.4). Immunohistochemistry identified a broad spectrum of NK-1 receptor locations in control intestine. No aberrant expression in IBD was found. This study showed that although there was no difference in location of the SP receptors in IBD patients versus controls, the quantity of SP binding was significantly increased in the inflamed mucosa of IBD patients, while the mRNA level was not increased. Further a difference in mRNA level between non-inflamed tissue of CD and UC patients was shown, with mRNA in CD being lower. These changes in SP receptor expression during chronic inflammation suggest that SP receptors are a potential target for therapeutic regulation of the inflammatory response.
- Published
- 2007
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47. Eradication of Helicobacter pylori infection favourably affects altered gastric mucosal MMP-9 levels.
- Author
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Kubben FJ, Sier CF, Schram MT, Witte AM, Veenendaal RA, van Duijn W, Verheijen JH, Hanemaaijer R, Lamers CB, and Verspaget HW
- Subjects
- Adult, Aged, Biopsy, Clarithromycin therapeutic use, Drug Therapy, Combination, Endoscopy, Gastrointestinal, Enzyme-Linked Immunosorbent Assay, Female, Helicobacter Infections microbiology, Humans, Male, Matrix Metalloproteinase 2 metabolism, Metronidazole therapeutic use, Middle Aged, Omeprazole therapeutic use, Ranitidine therapeutic use, Treatment Outcome, Anti-Infective Agents therapeutic use, Anti-Ulcer Agents therapeutic use, Gastric Mucosa metabolism, Helicobacter Infections drug therapy, Helicobacter pylori drug effects, Matrix Metalloproteinase 9 metabolism
- Abstract
Background: Helicobacter pylori gastritis is recognized as an important pathogenetic factor in peptic ulcer disease and gastric carcinogenesis, and is accompanied by strongly enhanced gastric mucosal matrix metalloproteinase-9 (MMP-9) levels., Aim: This study was performed to investigate whether H. pylori-affected gastric mucosal MMP-2 and MMP-9 levels are reversible by successful treatment of the infection., Patients and Methods: Fifty-eight patients with H. pylori-associated gastritis were treated with a combination regimen of acid inhibitory therapy and antibiotics for 14 days. The levels and isoforms of MMP-2 and MMP-9 were measured by semiquantitative gelatin-zymography, bioactivity assay and enzyme-linked immunosorbent assay in gastric mucosal biopsy homogenates., Results: Latent, active, and total MMP-9 levels decreased consistently and significantly by successful H. pylori eradication, in antrum as well as corpus mucosa, compared with those prior to treatment, irrespective of the therapy regimen used. The elevated levels remained unchanged, however, when treatment failed. MMP-2 levels did not show major alterations after H. pylori therapy., Conclusion: Elevated MMP-9 levels in H. pylori-infected gastric mucosa are reversible by eradication of the infection. No major changes in mucosal MMP-2 levels were observed by H. pylori eradication.
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- 2007
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48. Tissue level, activation and cellular localisation of TGF-beta1 and association with survival in gastric cancer patients.
- Author
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Hawinkels LJ, Verspaget HW, van Duijn W, van der Zon JM, Zuidwijk K, Kubben FJ, Verheijen JH, Hommes DW, Lamers CB, and Sier CF
- Subjects
- Aged, Female, Humans, Immunohistochemistry, Male, Middle Aged, Stomach Neoplasms physiopathology, Stomach Neoplasms metabolism, Survival Analysis, Transforming Growth Factor beta1 metabolism
- Abstract
Transforming growth factor-beta1 (TGF-beta1), a tumour suppressing as well as tumour-promoting cytokine, is stored as an extracellular matrix-bound latent complex. We examined TGF-beta1 activation and localisation of TGF-beta1 activity in gastric cancer. Gastric tumours showed increased stromal and epithelial total TGF-beta1 staining by immunohistochemistry. Active TGF-beta1 was present in malignant epithelial cells, but most strongly in smooth muscle actin expressing fibroblasts. Normal gastric mucosa from the same patient showed some staining for total, and little for active TGF-beta1. Active TGF-beta1 levels were determined by ELISA on tissue homogenates, confirming a strong increase in active TGF-beta1 in tumours compared to corresponding normal mucosa. Moreover, high tumour TGF-beta1 activity levels were significantly associated with clinical parameters, including worse survival of the patients. Total and active TGF-beta1 levels were not correlated, suggesting a specific activation process. Of the different proteases tested, active TGF-beta1 levels were only correlated with urokinase activity levels. The correlation with urokinase activity suggests a role for plasmin in TGF-beta1 activation in the tumour microenvironment, resulting in transformation of resident fibroblasts to tumour promoting myofibroblasts. In conclusion we have shown localisation and clinical relevance of TGF-beta1 activity levels in gastric cancer.
- Published
- 2007
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49. Clinical evidence for a protective role of lipocalin-2 against MMP-9 autodegradation and the impact for gastric cancer.
- Author
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Kubben FJ, Sier CF, Hawinkels LJ, Tschesche H, van Duijn W, Zuidwijk K, van der Reijden JJ, Hanemaaijer R, Griffioen G, Lamers CB, and Verspaget HW
- Subjects
- Acute-Phase Proteins metabolism, Adult, Aged, Aged, 80 and over, Female, Humans, Immunohistochemistry, Lipocalin-2, Lipocalins metabolism, Male, Middle Aged, Prognosis, Proto-Oncogene Proteins metabolism, Stomach Neoplasms mortality, Acute-Phase Proteins physiology, Lipocalins physiology, Matrix Metalloproteinase 9 metabolism, Proto-Oncogene Proteins physiology, Stomach Neoplasms metabolism
- Abstract
Recently, complexes of matrix metalloproteinase matrix metalloproteinase-9 (MMP-9) with lipocalin-2 (neutrophil gelatinase-associated lipocalin) were found in the urine obtained from breast cancer patients, while these were completely absent in that obtained from healthy controls. In vitro data suggested a possible role for lipocalin-2 in the protection of MMP-9 against autolysis. To establish this effect in vivo, we determined the presence of MMP-9, lipocalin-2 and their complex in tumour tissue from 81 gastric cancer patients. The effect of the presence of the individual parameters, the complexes, and the inhibitors TIMP-1 and TIMP-2 on MMP-9 activity was evaluated with a bioactivity assay. Immuno-histochemical (double) staining identified epithelial cells as the most likely cellular source. Finally, evaluation of all these parameters with clinico-pathological scores revealed that tumour MMP-9/lipocalin-2 complexes were significantly related with the classifications of Laurén and WHO, and highly associated with worse survival in Cox's univariate (HR 2.087, P=0.006) and multivariate analyses (HR 2.095, P=0.025).
- Published
- 2007
- Full Text
- View/download PDF
50. Increased mucosal matrix metalloproteinase-1, -2, -3 and -9 activity in patients with inflammatory bowel disease and the relation with Crohn's disease phenotype.
- Author
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Meijer MJ, Mieremet-Ooms MA, van der Zon AM, van Duijn W, van Hogezand RA, Sier CF, Hommes DW, Lamers CB, and Verspaget HW
- Subjects
- Biomarkers metabolism, Colitis, Ulcerative genetics, Colitis, Ulcerative pathology, Crohn Disease genetics, Crohn Disease pathology, Enzyme-Linked Immunosorbent Assay, Female, Follow-Up Studies, Humans, Intestinal Mucosa enzymology, Intestinal Mucosa pathology, Male, Phenotype, Prognosis, Prospective Studies, Severity of Illness Index, Colitis, Ulcerative enzymology, Crohn Disease enzymology, Matrix Metalloproteinase 1 biosynthesis, Matrix Metalloproteinase 2 biosynthesis, Matrix Metalloproteinase 3 biosynthesis, Matrix Metalloproteinase 9 biosynthesis
- Abstract
Background and Objective: Matrix metalloproteinases are associated with matrix turnover in both physiological and pathological conditions. We postulate an association between aberrant matrix metalloproteinases proteolytic activity and the intestinal tissue destruction, seen in patients with Crohn's disease and/or ulcerative colitis., Materials and Methods: Surgically resected inflamed and non-inflamed ileum and colon with/without extensive fibrosis from 122 Crohn's disease, 20 ulcerative colitis and 62 control patients were homogenized. Protein levels of matrix metalloproteinases and tissue inhibitor of metalloproteinases were measured by enzyme-linked immunosorbent assays (ELISA), while matrix metalloproteinases and myeloperoxidase activity were measured by specific activity assays., Results: Expression of total levels of matrix metalloproteinases-1, -2, -3 and -9 relative to tissue inhibitor of metalloproteinases-1 and -2 was increased in inflamed inflammatory bowel disease compared to non-inflamed inflammatory bowel disease and control intestinal mucosa. Also, net matrix metalloproteinases-1, -2, -3 and -9 activity in inflamed inflammatory bowel disease was increased, with similar expression profiles in Crohn's disease and ulcerative colitis. Within inflamed inflammatory bowel disease, a close correlation of matrix metalloproteinases with myeloperoxidase was observed. The expression of matrix metalloproteinases and tissue inhibitor of metalloproteinases was similar in inflamed Crohn's disease tissue with or without extensive fibrosis and not related to fistulizing disease., Conclusions: We have shown increased net matrix metalloproteinases activity in intestinal inflammatory bowel disease tissue, likely to contribute to the tissue damage and remodelling seen in inflammatory bowel disease.
- Published
- 2007
- Full Text
- View/download PDF
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