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Publications (2)2.43 Total impact

  • Article: Effects of EpCAM overexpression on human breast cancer cell lines
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    ABSTRACT: Abstract Background Recently, EpCAM has attracted major interest as a target for antibody- and vaccine-based cancer immunotherapies. In breast cancer, the EpCAM antigen is overexpressed in 30-40% of all cases and this increased expression correlates with poor prognosis. The use of EpCAM-specific monoclonal antibodies is a promising treatment approach in these patients. Methods In order to explore molecular changes following EpCAM overexpression, we investigated changes of the transcriptome upon EpCAM gene expression in commercially available human breast cancer cells lines Hs578T and MDA-MB-231. To assess cell proliferation, a tetrazolium salt based assay was performed. A TCF/LEF Reporter Kit was used to measure the transcriptional activity of the Wnt/β-catenin pathway. To evaluate the accumulation of β-catenin in the nucleus, a subcellular fractionation assay was performed. Results For the first time we could show that expression profiling data of EpCAM transfected cell lines Hs578TEpCAM and MDA-MB-231EpCAM indicate an association of EpCAM overexpression with the downregulation of the Wnt signaling inhibitors SFRP1 and TCF7L2. Confirmation of increased Wnt signaling was provided by a TCF/LEF reporter kit and by the finding of the nuclear accumulation of ß-catenin for MDA-MB-231EpCAM but not Hs578TEpCAM cells. In Hs578T cells, an increase of proliferation and chemosensitivity to Docetaxel was associated with EpCAM overexpression. Conclusions These data show a cell type dependent modification of Wnt signaling components after EpCAM overexpression in breast cancer cell lines, which results in marginal functional changes. Further investigations on the interaction of EpCAM with SFRP1 and TCF7L2 and on additional factors, which may be causal for changes upon EpCAM overexpression, will help to characterize unique molecular properties of EpCAM-positive breast cancer cells.
    BMC Cancer. 01/2011;
  • Article: TROP2 expression as prognostic marker for gastric carcinoma.
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    ABSTRACT: In gastric cancer the recurrence rate is unacceptably high, even after R0 resection and (neo)adjuvant chemotherapy. Therefore, there is an urgent need for identification of predictive and/or prognostic biomarkers to select high-risk patients who might benefit from additional therapies. Expression of TROP2 has been shown to be associated with tumour aggressiveness and poor prognosis in patients with various epithelial cancers. To investigate TROP2 expression in gastric cancer and its correlation with clinicopathological features and disease outcome. Expression of TROP2 was investigated by immunohistochemistry of tumour specimens from 104 patients who underwent resection for gastric cancer. Parameters found to be of prognostic significance in univariate analysis were verified in a multivariate Cox regression model. TROP2 was found to be overexpressed in 58 (56%) tumour samples. Significantly higher expression of TROP2 could be detected in intestinal-type carcinomas (p = 0.03). In intestinal-type gastric cancer, TROP2 overexpression was significantly correlated with shorter disease-free survival (DFS) (p = 0.03). Among the total group, TROP2 overexpression was predictive for poor disease-free (p<0.01) and overall (p = 0.03) survival in lymph node positive patients. Multivariate Cox regression analysis revealed TROP2 overexpression to be an independent prognostic marker for poor DFS in the subgroup of patients with intestinal-type gastric cancer irrespective of lymph node involvement. Results show that TROP2 is an independent prognostic marker for disease recurrence in intestinal type gastric cancer. Due to its wide distribution TROP2 may become an attractive therapeutic target in a subgroup of patients with gastric cancer.
    Journal of clinical pathology 10/2008; 62(2):152-8. · 2.43 Impact Factor