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61.
Carsten Denkert Wilko Weichert Klaus-Jürgen Winzer Berit-Maria Müller Aurelia Noske Silvia Niesporek Glen Kristiansen Hans Guski Manfred Dietel Steffen Hauptmann 《Clinical cancer research》2004,10(16):5580-5586
PURPOSE: The human ELAV (embryonic lethal abnormal vision)-like protein HuR stabilizes a certain group of cellular mRNAs that contain AU-rich elements in their 3'-untranslated region. Cell culture studies have shown that the mRNA of cyclooxygenase (COX)-2 can be stabilized by HuR. EXPERIMENTAL DESIGN: To investigate a possible contribution of dysregulation of mRNA stability to the progression of cancer and to overexpression of COX-2, we studied expression of HuR in 208 primary breast carcinomas by immunohistochemistry. RESULTS: There were two different staining patterns of HuR in tumor tissue of breast carcinomas: nuclear expression was seen in 61% of cases; and an additional cytoplasmic expression was seen in 30% of cases. Expression of HuR was significantly associated with increased COX-2 expression; this association was particularly significant for cytoplasmic HuR expression (P < 0.0005). We further observed a significant association of cytoplasmic (P = 0.002) or nuclear HuR (P = 0.027) expression with increased tumor grade. Only 13% of the grade 1 carcinomas showed cytoplasmic expression of HuR, compared with 46% of the grade 3 carcinomas. There was no significant correlation between HuR expression and other clinicopathological parameters such as histological type, tumor size, or nodal status as well as patient survival. CONCLUSIONS: Our results suggest that overexpression of HuR in tumor tissue may be part of a regulatory pathway that controls the mRNA stability of several important targets in tumor biology, such as COX-2. Based on our results, additional studies are necessary to investigate whether HuR might be a potential target for molecular tumor therapy. 相似文献
62.
Regine Schneider-Stock Carsten Boltze Jerzy Lasota Markku Miettinen Brigitte Peters Matthias Pross Albert Roessner Thomas Günther 《Journal of clinical oncology》2003,21(9):1688-1697
PURPOSE: Gastrointestinal stromal tumors (GISTs) represent a distinctive (but histologically heterogeneous) group of neoplasms, the malignant potential of which is often uncertain. To determine the prognostic relevance of p16INK4 alterations in GISTs, we investigated a larger group of GISTs and correlated the genetic findings with clinicopathological factors and patient survival. MATERIAL AND METHODS: We evaluated the methylation status of the promotor by methylation-specific polymerase chain reaction (PCR), the presence of mutations by PCR-SSCP-sequencing, the loss of heterozygosity at the p16INK4 locus (using the c5.1 marker), and the immunohistochemical expression of p16INK4 protein in 43 GISTs in 39 patients. RESULTS: p16INK4 alterations were found in 25 of 43 GISTs (58.1%), with benign, borderline, or malignant GISTs showing no differences in the type and frequency of alteration. p16INK4 alterations were correlated with a loss of p16INK4 protein expression (P <.01). Patients who had tumors with p16INK4 alterations had a poorer prognosis than patients with tumors without such alterations (P =.02). There was a high predictive value for p16INK4 alterations only in the group of benign and borderline GISTs (P <.01) with regard to clinical outcome. Univariate Cox's proportional hazard regression analysis revealed a strong correlation between p16INK4 alterations, tumor size, mitotic index, and overall survival (P <.02), whereas multivariate Cox's analysis confirmed only p16INK4 alterations as an independent prognostic factor. CONCLUSION: We believe that the evaluation of p16INK4 alteration status is a helpful prognosticator, particularly in the benign and borderline groups of GISTs. 相似文献
63.
Frank Mayer Hans Stoop George L Scheffer Rik Scheper J Wolter Oosterhuis Leendert H J Looijenga Carsten Bokemeyer 《Clinical cancer research》2003,9(2):767-773
PURPOSE: Germ cell tumors (GCTs) are highly sensitive to cisplatin-based chemotherapy. This feature is unexplained, as is the intrinsic chemotherapy resistance of mature teratomas and the resistant phenotype of a minority of refractory GCTs. Various cellular pathways may influence the efficacy of chemotherapy. Their impact has not been investigated in a comprehensive study of tumor samples from clinically defined subgroups of GCT patients. EXPERIMENTAL DESIGN: We investigated proteins involved in regulation of apoptosis (p53, BAX, BCL-2, and BCL-X(L)), cell cycle control [p21 and retinoblastoma protein (RB)], and drug export and inactivation [P-glycoprotein, multidrug resistance-associated protein (MRP) 1, MRP2, breast cancer resistance protein, lung resistance protein, metallothionein, and glutathione S-transferase pi] immunohistochemically in samples of unselected GCT patients (n = 20), patients with advanced metastatic disease in continuous remission after first-line chemotherapy (n = 12), and chemotherapy-refractory patients (n = 24). Mature teratoma components (n = 10) within tumor samples from all groups were analyzed separately. The apoptotic index was studied by terminal deoxynucleotidyl transferase-mediated nick end labeling assay. RESULTS: Invasive GCTs of all groups showed a correlation between wild-type p53 and apoptotic index (r(s) = 0.66; P < 0.001). The levels of the antiapoptotic proteins BCL-2 and BCL-X(L) were generally low. p21 was hardly detectable and did not correlate with p53 (r(s) = 0.29; P = 0.07). No significant differences among the three patient groups were identified regarding any of the investigated parameters (all Ps were >0.08), even though only individual samples from chemotherapy-resistant cases showed a strong staining for MRP2 and GSTpi. In contrast to other components, mature teratomas showed an intense p21 and RB staining and were mostly positive for MRP2, lung resistance protein, and GSTpi. CONCLUSIONS: Our results indicate a multifactorial basis for the chemosensitivity of GCTs with lack of transporters for cisplatin, of antiapoptotic BCL-2 family members, of p21 induction by p53, and of RB and an intact apoptotic cascade downstream of p53. These findings suggest a preference for apoptosis over cell cycle arrest after up-regulation of p53. None of the examined parameters offers a general explanation for the chemotherapy-resistant phenotype of refractory tumors. The up-regulation of various factors interfering with chemotherapy efficacy and ability for a p21-induced cell cycle arrest may explain the intrinsic chemotherapy resistance of mature teratomas. 相似文献
64.
Lise Borgwardt Liselotte H?jgaard Henrik Carstensen Henning Laursen Markus Nowak Carsten Thomsen Kjeld Schmiegelow 《Journal of clinical oncology》2005,23(13):3030-3037
PURPOSE Positron emission tomography (PET) has been used in grading of CNS tumors in adults, whereas studies of children have been limited. PATIENTS AND METHODS Nineteen boys and 19 girls (median age, 8 years) with primary CNS tumors were studied prospectively by fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) PET with (n = 16) or without (n = 22) H(2)(15)O-PET before therapy. Image processing included coregistration to magnetic resonance imaging (MRI) in all patients. The FDG uptake in tumors was semiquantitatively calculated by a region-of-interest-based tumor hotspot/brain index. Eight tumors without histologic confirmation were classified as WHO grade 1 based on location, MRI, and clinical course (22 to 42 months). Results Four grade 4 tumors had a mean index of 4.27 +/- 0.5, four grade 3 tumors had a mean index of 2.47 +/- 1.07, 10 grade 2 tumors had a mean index of 1.34 +/- 0.73, and eight of 12 grade 1 tumors had a mean index of -0.31 +/- 0.59. Eight patients with no histologic confirmation had a mean index of 1.04. For these 34 tumors, FDG uptake was positively correlated with malignancy grading (n = 34; r = 0.72; P < .01), as for the 26 histologically classified tumors (n = 26; r = 0.89; P < .01). The choroid plexus papilloma (n = 1) and the pilocytic astrocytomas (n = 3) had a mean index of 3.26 (n = 38; r = 0.57; P < .01). H(2)(15)O-uptake showed no correlation with malignancy. Digitally performed PET/MRI coregistration increased information on tumor characterization in 90% of cases. CONCLUSION FDG PET of the brain with MRI coregistration can be used to obtain a more specific diagnosis with respect to malignancy grading. Improved PET/MRI imaging of the benign hypermetabolic tumors is needed to optimize clinical use. 相似文献
65.
66.
Emilie Brard Christoph Rllig Sarah Bertoli Arnaud Pigneux Suzanne Tavitian Michael Kramer Hubert Serve Martin Bornhuser Uwe Platzbecker Carsten Müller-Tidow Claudia D. Baldus David Martínez-Cuadrn Josefina Serrano Pilar Martínez-Snchez Eduardo Rodríguez Arbolí Cristina Gil Juan Bergua Teresa Bernal Adolfo de la Fuente Burguera Eric Delabesse Audrey Bidet Pierre-Yves Dumas Pau Montesinos Christian Rcher 《Blood cancer journal》2022,12(7)
In a context of therapeutic revolution in older adults with AML, it is becoming increasingly important to select patients for the various treatment options by taking account of short-term efficacy and toxicity as well as long-term survival. Here, the data from three European registries for 1,199 AML patients aged 70 years or older treated with intensive chemotherapy were used to develop a prognostic scoring system. The median follow-up was 50.8 months. In the training set of 636 patients, age, performance status, secondary AML, leukocytosis, and cytogenetics, as well as NPM1 mutations (without FLT3-ITD), were all significantly associated with overall survival, albeit not to the same degree. These factors were used to develop a score that predicts long-term overall survival. Three risk-groups were identified: a lower, intermediate and higher-risk score with predicted 5-year overall survival (OS) probabilities of ≥12% (n = 283, 51%; median OS = 18 months), 3–12% (n = 226, 41%; median OS = 9 months) and <3% (n = 47, 8%; median OS = 3 months), respectively. This scoring system was also significantly associated with complete remission, early death and relapse-free survival; performed similarly in the external validation cohort (n = 563) and showed a lower false-positive rate than previously published scores. The European Scoring System ≥70, easy for routine calculation, predicts long-term survival in older AML patients considered for intensive chemotherapy.Subject terms: Acute myeloid leukaemia, Risk factors 相似文献
67.
68.
69.
Richter-Ehrenstein C Tombokan F Fallenberg EM Schneider A Denkert C 《Breast (Edinburgh, Scotland)》2011,20(6):501-504
Introduction
The assessment of papillary lesions continues to be a challenging area in breast radiology and pathology. The management of intraductal papillomas without atypia of the breast remains controversial. The purpose of the present study was to determine diagnostic accuracy of radiographical diagnosis, core biopsy, and surgical excision in papillary breast lesions.Material and methods
By using files from 1995 to 2010, 151 cases of intraductal papilloma with or without atypia were identified. Patients were stratified as follows: core biopsy followed by surgical excision (n = 61), core biopsy alone (n = 19), and surgical excision alone (n = 71).Results
The upstage rate of intraductal papillomas without atypia on core biopsy to atypia or malignancy on excision was 8.9%. Excision specimens revealed intraductal papillomas without atypia in 68 out of 71 cases, and atypical papillomas in 3 cases.Conclusion
Our findings suggest that radiographic and histopathological diagnosis of intraductal papillomas show high accuracy and good concordance. In cases where the radiographic diagnosis reveals suspicious lesions core biopsy represents the first choice. 相似文献70.
(1) Background: Mitochondria are the cells’ main source of energy. Mitochondrial dysfunction represents a key hallmark of aging and is linked to the development of Alzheimer’s disease (AD). Maintaining mitochondrial function might contribute to healthy aging and the prevention of AD. The Mediterranean diet, including walnuts, seems to prevent age-related neurodegeneration. Walnuts are a rich source of α-linolenic acid (ALA), an essential n3-fatty acid and the precursor for n3-long-chain polyunsaturated fatty acids (n3-PUFA), which might potentially improve mitochondrial function. (2) Methods: We tested whether a lipophilic walnut extract (WE) affects mitochondrial function and other parameters in human SH-SY5Y cells transfected with the neuronal amyloid precursor protein (APP695). Walnut lipids were extracted using a Soxhlet Extraction System and analyzed using GC/MS and HPLC/FD. Adenosine triphosphate (ATP) concentrations were quantified under basal conditions in cell culture, as well as after rotenone-induced stress. Neurite outgrowth was investigated, as well as membrane integrity, cellular reactive oxygen species, cellular peroxidase activity, and citrate synthase activity. Beta-amyloid (Aβ) was quantified using homogenous time-resolved fluorescence. (3) Results: The main constituents of WE are linoleic acid, oleic acid, α-linolenic acid, and γ- and δ-tocopherol. Basal ATP levels following rotenone treatment, as well as citrate synthase activity, were increased after WE treatment. WE significantly increased cellular reactive oxygen species but lowered peroxidase activity. Membrane integrity was not affected. Furthermore, WE treatment reduced Aβ1–40 and stimulated neurite growth. (4) Conclusions: WE might increase ATP production after induction of mitochondrial biogenesis. Decreased Aβ1–40 formation and enhanced ATP levels might enhance neurite growth, making WE a potential agent to enhance neuronal function and to prevent the development of AD. In this sense, WE could be a promising agent for the prevention of AD. 相似文献