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Dive into the research topics where Christian Schem is active.

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Featured researches published by Christian Schem.


Journal of Clinical Oncology | 2015

Tumor-Infiltrating Lymphocytes and Response to Neoadjuvant Chemotherapy With or Without Carboplatin in Human Epidermal Growth Factor Receptor 2–Positive and Triple-Negative Primary Breast Cancers

Carsten Denkert; Gunter von Minckwitz; Jan C. Brase; Bruno V. Sinn; Stephan Gade; Ralf Kronenwett; Berit M. Pfitzner; Christoph Salat; Sherene Loi; Wolfgang D. Schmitt; Christian Schem; Karin Fisch; Silvia Darb-Esfahani; Keyur Mehta; Christos Sotiriou; Stephan Wienert; P Klare; Fabrice Andre; Frederick Klauschen; Jens-Uwe Blohmer; Kristin Krappmann; Marcus Schmidt; Hans Tesch; Sherko Kümmel; Peter Sinn; Christian Jackisch; Manfred Dietel; Toralf Reimer; Michael Untch; Sibylle Loibl

PURPOSE Modulation of immunologic interactions in cancer tissue is a promising therapeutic strategy. To investigate the immunogenicity of human epidermal growth factor receptor 2 (HER2) -positive and triple-negative (TN) breast cancers (BCs), we evaluated tumor-infiltrating lymphocytes (TILs) and immunologically relevant genes in the neoadjuvant GeparSixto trial. PATIENTS AND METHODS GeparSixto investigated the effect of adding carboplatin (Cb) to an anthracycline-plus-taxane combination (PM) on pathologic complete response (pCR). A total of 580 tumors were evaluated before random assignment for stromal TILs and lymphocyte-predominant BC (LPBC). mRNA expression of immune-activating (CXCL9, CCL5, CD8A, CD80, CXCL13, IGKC, CD21) as well as immunosuppressive factors (IDO1, PD-1, PD-L1, CTLA4, FOXP3) was measured in 481 tumors. RESULTS Increased levels of stromal TILs predicted pCR in univariable (P < .001) and multivariable analyses (P < .001). pCR rate was 59.9% in LPBC and 33.8% for non-LPBC (P < .001). pCR rates ≥ 75% were observed in patients with LPBC tumors treated with PMCb, with a significant test for interaction with therapy in the complete (P = .002) and HER2-positive (P = .006), but not the TNBC, cohorts. Hierarchic clustering of mRNA markers revealed three immune subtypes with different pCR rates (P < .001). All 12 immune mRNA markers were predictive for increased pCR. The highest odds ratios (ORs) were observed for PD-L1 (OR, 1.57; 95% CI, 1.34 to 1.86; P < .001) and CCL5 (OR, 1.41; 95% CI, 1.23 to 1.62; P < .001). CONCLUSION Immunologic factors were highly significant predictors of therapy response in the GeparSixto trial, particularly in patients treated with Cb. After further standardization, they could be included in histopathologic assessment of BC.


Virchows Archiv | 2009

One-step nucleic acid amplification-a molecular method for the detection of lymph node metastases in breast cancer patients; results of the German study group.

Christian Schem; Nicolai Maass; Dirk O. Bauerschlag; Martin H. Carstensen; Thomas Löning; Christian Roder; Olivera Batic; Walter Jonat; Katharina Tiemann

Sentinel lymph node (SN) biopsy is part of the staging procedure in breast cancer patients. In this study, we compared an intraoperative tool named one-step nucleic acid amplification (OSNA) to our routine histological investigation. OSNA consists of a short homogenization step followed by amplification of cytokeratin (CK) 19 mRNA directly from the lysate. To evaluate the performance of OSNA in comparison to histology, analysis of 343 axillary lymph nodes (ALN) from 93 breast cancer patients was performed with both methods. Discordant samples were subjected to other methods. If these tests supported the OSNA results, these samples were excluded from the study. The concordance rate was 91.8%, sensitivity 98.1%, and specificity 90.8% before and 95.5%, 100%, and 95.6%, respectively, after discordant case investigation. Our results show that OSNA is an excellent method for the detection of metastases in lymph nodes and can be applied as an intraoperative diagnostic approach.


International Journal of Cancer | 2003

Leucine-zipper protein, LDOC1, inhibits NF-κB activation and sensitizes pancreatic cancer cells to apoptosis†

Koichi Nagasaki; Christian Schem; Constantin von Kaisenberg; Marco Biallek; Frank Rösel; Walter Jonat; Nicolai Maass

We have isolated a novel gene, LDOC1, which encodes for a leucine zipper protein that was downregulated in a series of human pancreatic cancer cell lines but was expressed in corresponding normal tissues. We report the initial characterization of LDOC1 as a novel regulator of the transcriptional response mediated by the nuclear factor kappa B (NF‐κB). Transient expression of LDOC1 significantly inhibited the luciferase activity in LDOC1‐negative BxPC‐3 pancreatic cancer cell line transfected with the NF‐κB reporter plasmid, activated with mitogen‐activated protein kinase/ERK kinase kinase‐1 (MEEK). LDOC1, however, does not affect p53, AP1 and CRE‐dependent reporter gene expression. The activation of NF‐κB through ligand‐induced stimulation by tumor necrosis factor‐α (TNF‐α) or phorbol 12‐myristate 13‐acetate (PMA) was also inhibited by transient expression of LDOC1 in a dose dependent manner. To determine the growth effect of LDOC1 expression on cancer cells, BxPC‐3 cells were stably transfected with LDOC1 cDNA. Viability studies demonstrated that TNF‐α or PMA‐induced antiproliferative effects were significantly enhanced by stable transfection of cells with LDOC1. These observations suggest that LDOC1 is a novel regulator of NF‐κB that can affect the PMA or TNF‐α‐mediated pathway to apoptosis through inhibition of NF‐κB activation in BxPC3 pancreatic cancer cells.


Human Mutation | 2011

Germline mutations in the PALB2 gene are population specific and occur with low frequencies in familial breast cancer

Heide Hellebrand; Christian Sutter; Ellen Honisch; Eva Gross; Barbara Wappenschmidt; Christian Schem; Helmut Deissler; Nina Ditsch; Verena Gress; Marion Kiechle; Claus R. Bartram; Rita K. Schmutzler; Dieter Niederacher; Norbert Arnold; Alfons Meindl

The Partner and Localizer of BRCA2 (PALB2) protein has been linked to Fanconi anemia and breast cancer predisposition. Here we present data of a comprehensive mutation screening of the PALB2 gene in 818 familial cases of breast cancer from Germany. By analysing the entire coding region of PALB2, we found seven truncating mutations (six of them novel) in families tested negative for BRCA1/2‐mutations. In addition, two novel potentially disease causing missense mutations were found. Remarkably, only one mutation reported previously in other populations, was also identified in the German population. No PALB2 mutation carriers were identidfied in 450 unaffected controls. Thus, our observations indicate a low prevalence of deleterious PALB2 mutations and a specific mutation profile within the German population. As PALB2‐deficient tumors were shown to be sensitive to Poly(ADP‐ribose) Polymerase (PARP) inhibitors, our study has implications for newly developed, favourable treatment options in familial breast cancer.


BMC Cancer | 2010

In vitro effects of imatinib mesylate on radiosensitivity and chemosensitivity of breast cancer cells

Marion T. Weigel; Linda Dahmke; Christian Schem; Dirk O. Bauerschlag; Katrin Weber; Peter Niehoff; Maret Bauer; Alexander Strauss; Walter Jonat; Nicolai Maass; Christoph Mundhenke

BackgroundBreast cancer treatment is based on a combination of adjuvant chemotherapy followed by radiotherapy effecting intracellular signal transduction. With the tyrosine kinase inhibitors new targeted drugs are available. Imatinib mesylate is a selective inhibitor of bcr-abl, PRGFR alpha, beta and c-kit. The purpose of this study was to determine whether Imatinib has an influence on the effectiveness of radiotherapy in breast cancer cell lines and if a combination of imatinib with standard chemotherapy could lead to increased cytoreduction.MethodsColony-forming tests of MCF 7 and MDA MB 231 were used to study differences in cell proliferation under incubation with imatinib and radiation. Changes in expression and phosphorylation of target receptors were detected using western blot. Cell proliferation, migration and apoptosis assays were performed combining imatinib with doxorubicin.ResultsThe combination of imatinib and radiotherapy showed a significantly stronger inhibition of cell proliferation compared to single radiotherapy. Differences in PDGFR expression could not be detected, but receptor phosphorylation was significantly inhibited when treated with imatinib. Combination of imatinib with standard chemotherapy lead to an additive effect on cell growth inhibition compared to single treatment.ConclusionsImatinib treatment combined with radiotherapy leads in breast cancer cell lines to a significant benefit which might be influenced through inhibition of PDGFR phosphorylation. Combining imatinib with chemotherapy enhances cytoreductive effects. Further in vivo studies are needed to evaluate the benefit of Imatinib in combination with radiotherapy and chemotherapy on the treatment of breast cancer.


PLOS ONE | 2012

Neutrophil Gelatinase-Associated Lipocalin (NGAL) Predicts Response to Neoadjuvant Chemotherapy and Clinical Outcome in Primary Human Breast Cancer

Antonia Wenners; Keyur Mehta; Sibylle Loibl; Hyerim Park; Berit Mueller; Norbert Arnold; Sigrid Hamann; Joerg Weimer; Beyhan Ataseven; Silvia Darb-Esfahani; Christian Schem; Christoph Mundhenke; Fariba Khandan; Christoph Thomssen; Walter Jonat; Hans Juergen Holzhausen; Gunther von Minckwitz; Carsten Denkert; Maret Bauer

In our previous work we showed that NGAL, a protein involved in the regulation of proliferation and differentiation, is overexpressed in human breast cancer (BC) and predicts poor prognosis. In neoadjuvant chemotherapy (NACT) pathological complete response (pCR) is a predictor for outcome. The aim of this study was to evaluate NGAL as a predictor of response to NACT and to validate NGAL as a prognostic factor for clinical outcome in patients with primary BC. Immunohistochemistry was performed on tissue microarrays from 652 core biopsies from BC patients, who underwent NACT in the GeparTrio trial. NGAL expression and intensity was evaluated separately. NGAL was detected in 42.2% of the breast carcinomas in the cytoplasm. NGAL expression correlated with negative hormone receptor (HR) status, but not with other baseline parameters. NGAL expression did not correlate with pCR in the full population, however, NGAL expression and staining intensity were significantly associated with higher pCR rates in patients with positive HR status. In addition, strong NGAL expression correlated with higher pCR rates in node negative patients, patients with histological grade 1 or 2 tumors and a tumor size <40 mm. In univariate survival analysis, positive NGAL expression and strong staining intensity correlated with decreased disease-free survival (DFS) in the entire cohort and different subgroups, including HR positive patients. Similar correlations were found for intense staining and decreased overall survival (OS). In multivariate analysis, NGAL expression remained an independent prognostic factor for DFS. The results show that in low-risk subgroups, NGAL was found to be a predictive marker for pCR after NACT. Furthermore, NGAL could be validated as an independent prognostic factor for decreased DFS in primary human BC.


Oncology | 2011

Progression-free survival in ovarian cancer is reflected in epigenetic DNA methylation profiles.

Dirk O. Bauerschlag; Ole Ammerpohl; Karen Bräutigam; Christian Schem; Qiong Lin; Marion T. Weigel; Felix Hilpert; Norbert Arnold; Nicolai Maass; Ivo Meinhold-Heerlein; Wolfgang Wagner

Objective: Many patients with ovarian cancer disease relapse within 6 months after adjuvant chemotherapy, with a limited prognosis. Epigenetic modifications have been shown to play an important role in tumor development and formation. Therefore, global analysis of DNA methylation patterns might reveal specific CpG sites that correlate with progression-free interval (PFI) after therapy. Methods: Twenty samples of advanced ovarian cancer with a predominantly serous papillary histological subtype were subjected to DNA methylation profiling. Illumina HumanMethylation27 BeadChip technology was used for simultaneous analysis of 27,578 CpG sites in >14,000 genes. Results: Differential DNA methylation of various cytosines correlated with PFI. However, this becomes only significant by classification according to PFI with a cutoff of >28 months. Longer survival was associated with hypomethylation at specific CpG sites (e.g. GREB1, TGIF and TOB1) and hypermethylation in other genes (e.g. TMCO5, PTPRN and GUCY2C). Gene ontology analysis revealed that differentially methylated genes were significantly overrepresented in the categories telomere organization, mesoderm development and immune regulation. Conclusion: Epigenetic modifications at specific CpG sites correlate with PFI in ovarian cancer. Therefore, such analysis might be of prognostic value.


Annals of Oncology | 2016

PIK3CA mutations are associated with reduced pathological complete response rates in primary HER2-positive breast cancer: pooled analysis of 967 patients from five prospective trials investigating lapatinib and trastuzumab

Sibylle Loibl; Ian Majewski; Valentina Guarneri; Valentina Nekljudova; Eileen Holmes; Emilio Bria; Carsten Denkert; Christian Schem; Christos Sotiriou; Sherene Loi; Michael Untch; Pierfranco Conte; René Bernards; Martine Piccart; G. von Minckwitz; José Baselga

BACKGROUND The predictive value of PIK3CA mutations in HER2 positive (HER2+) breast cancer treated with neoadjuvant anti-HER2 and chemotherapy has been reported, but the power for subgroup analyses was lacking. PATIENTS AND METHODS We combined individual patient data from five clinical trials evaluating PIK3CA mutations and associations with pathological complete response (pCR), disease-free survival (DFS) and overall survival (OS). Patients received either trastuzumab (T), lapatinib (L) or the combination T/L in addition to a taxane-based chemotherapy. PIK3CA was genotyped in tumour biopsies taken before therapy. RESULTS A total of 967 patients were included in this analysis; the median follow-up is 47 months. Overall, the pCR rate was significantly lower in the PIK3CA mutant compared with the wild-type group (16.2% versus 29.6%; P < 0.001). Within the hormone-receptor positive (HR+) subgroup, the PIK3CA mutant group had a pCR rate of only 7.6% compared with 24.2% in the wild-type group (P < 0.001). In contrast, in the HER2+/HR- group, there was no difference in pCR (27.2% versus 36.4%; P = 0.125) according to PIK3CA mutation status (interaction test P = 0.036). According to treatment arm, the pCR rate for mutant versus wild-type was 20.3% versus 27.1% for T (P = 0.343), 11.3% versus 16.9% for L (P = 0.369) and 16.7% versus 39.1% for T/L (P < 0.001). In the HR+ T/L group, the pCR rate was 5.5% versus 33.9% (interaction between HR and PIK3CA genotype P = 0.008). DFS and OS were not significantly different by mutation status, though the incidence rate of events was low. However, HR+/PIK3CA mutant patients seemed to have significantly worse DFS {hazard ratio (HR) 1.56 [95% confidence interval (CI) 1.00-2.45], P = 0.050; Pinteraction = 0.021}. T/L tended to improve DFS compared with T in the wild-type cohort, especially in the HR- group [HR 0.72, 95% CI (0.41-1.25), P = 0.242]. CONCLUSION Overall PIK3CA mutant/HER2+ tumours had significantly lower pCR rates compared with wild-type tumours, however mainly confined to the HR+/PIK3CA mutant population. No definite conclusions can be drawn regarding survival.


Lancet Oncology | 2018

Tumour-infiltrating lymphocytes and prognosis in different subtypes of breast cancer: a pooled analysis of 3771 patients treated with neoadjuvant therapy

Carsten Denkert; Gunter von Minckwitz; Silvia Darb-Esfahani; Bianca Lederer; Barbara I Heppner; Karsten Weber; Jan Budczies; Jens Huober; Frederick Klauschen; Jenny Furlanetto; Wd Schmitt; Jens-Uwe Blohmer; Thomas Karn; Berit M Pfitzner; Sherko Kümmel; Knut Engels; Andreas Schneeweiss; Arndt Hartmann; Aurelia Noske; Peter A. Fasching; Christian Jackisch; Marion van Mackelenbergh; Peter Sinn; Christian Schem; Claus Hanusch; Michael Untch; Sibylle Loibl

BACKGROUND Tumour-infiltrating lymphocytes (TILs) are predictive for response to neoadjuvant chemotherapy in triple-negative breast cancer (TNBC) and HER2-positive breast cancer, but their role in luminal breast cancer and the effect of TILs on prognosis in all subtypes is less clear. Here, we assessed the relevance of TILs for chemotherapy response and prognosis in patients with TNBC, HER2-positive breast cancer, and luminal-HER2-negative breast cancer. METHODS Patients with primary breast cancer who were treated with neoadjuvant combination chemotherapy were included from six randomised trials done by the German Breast Cancer Group. Pretherapeutic core biopsies from 3771 patients included in these studies were assessed for the number of stromal TILs by standardised methods according to the guidelines of the International TIL working group. TILs were analysed both as a continuous parameter and in three predefined groups of low (0-10% immune cells in stromal tissue within the tumour), intermediate (11-59%), and high TILs (≥60%). We used these data in univariable and multivariable statistical models to assess the association between TIL concentration and pathological complete response in all patients, and between the amount of TILs and disease-free survival and overall survival in 2560 patients from five of the six clinical trial cohorts. FINDINGS In the luminal-HER2-negative breast cancer subtype, a pathological complete response (pCR) was achieved in 45 (6%) of 759 patients with low TILs, 48 (11%) of 435 with intermediate TILs, and 49 (28%) of 172 with high TILs. In the HER2-positive subtype, pCR was observed in 194 (32%) of 605 patients with low TILs, 198 (39%) of 512 with intermediate TILs, and 127 (48%) of 262 with high TILs. Finally, in the TNBC subtype, pCR was achieved in 80 (31%) of 260 patients with low TILs, 117 (31%) of 373 with intermediate TILs, and 136 (50%) of 273 with high TILs (p<0·0001 for each subtype, χ2 test for trend). In the univariable analysis, a 10% increase in TILs was associated with longer disease-free survival in TNBC (hazard ratio [HR] 0·93 [95% CI 0·87-0·98], p=0·011) and HER2-positive breast cancer (0·94 [0·89-0·99], p=0·017), but not in luminal-HER2-negative tumours (1·02 [0·96-1·09], p=0·46). The increase in TILs was also associated with longer overall survival in TNBC (0·92 [0·86-0·99], p=0·032), but had no association in HER2-positive breast cancer (0·94 [0·86-1·02], p=0·11), and was associated with shorter overall survival in luminal-HER2-negative tumours (1·10 [1·02-1·19], p=0·011). INTERPRETATION Increased TIL concentration predicted response to neoadjuvant chemotherapy in all molecular subtypes assessed, and was also associated with a survival benefit in HER2-positive breast cancer and TNBC. By contrast, increased TILs were an adverse prognostic factor for survival in luminal-HER2-negative breast cancer, suggesting a different biology of the immunological infiltrate in this subtype. Our data support the hypothesis that breast cancer is immunogenic and might be targetable by immune-modulating therapies. In light of the results in luminal breast cancer, further research investigating the interaction of the immune system with different types of endocrine therapy is warranted. FUNDING Deutsche Krebshilfe and European Commission.


JAMA Oncology | 2017

Germline Mutation Status, Pathological Complete Response, and Disease-Free Survival in Triple-Negative Breast Cancer: Secondary Analysis of the GeparSixto Randomized Clinical Trial

Eric Hahnen; Bianca Lederer; Jan Hauke; Sibylle Loibl; Sandra Kröber; Andreas Schneeweiss; Carsten Denkert; Peter A. Fasching; Jens Uwe Blohmer; Christian Jackisch; Stefan Paepke; Bernd Gerber; Sherko Kümmel; Christian Schem; Guido Neidhardt; Jens Huober; Kerstin Rhiem; Serban D. Costa; Janine Altmüller; Claus Hanusch; Holger Thiele; Volkmar Müller; Peter Nürnberg; Thomas Karn; Valentina Nekljudova; Michael Untch; Gunter von Minckwitz; Rita K. Schmutzler

Importance The GeparSixto trial provided evidence that the addition of neoadjuvant carboplatin to a regimen consisting of anthracycline, taxane, and bevacizumab increases pathological complete response (pCR) rates in patients with triple-negative breast cancer (TNBC). Whether BRCA1 and BRCA2 germline mutation status affects treatment outcome remains elusive. Objective To determine whether BRCA1 and BRCA2 germline mutation status affects therapy response in patients with TNBC. Design, Setting, and Participants This secondary analysis of a randomized clinical trial used archived DNA samples and cancer family history of 315 patients with TNBC enrolled between August 1, 2011, and December 31, 2012, in the GeparSixto trial. In all, 291 participants (92.4%) were included in this multicenter prospective investigation. DNA samples were analyzed for germline mutations in BRCA1, BRCA2, and 16 other cancer predisposition genes. The pCR rates between the carboplatin and noncarboplatin arms were compared. Genetic analyses were performed at the Center for Familial Breast and Ovarian Cancer in Cologne, Germany; data analysis, November 1 through December 31, 2015. Main Outcomes and Measures Proportion of patients who achieved pCR and disease-free survival after neoadjuvant treatment according to BRCA1 and BRCA2 germline mutation status. For pCR rates, the ypT0/is ypN0 definition was used as a primary end point. Results Of the 291 patients with TNBC, all were women; the mean (SD) age was 48 (11) years. The pCR rate in the carboplatin group was 56.8% (83 of 146) and 41.4% (60 of 145) in the noncarboplatin group (odds ratio [OR], 1.87; 95% CI, 1.17-2.97; P = .009). Pathogenic BRCA1 and BRCA2 germline mutations were present in 50 of the 291 patients (17.2%). In the noncarboplatin arm, the pCR rate was 66.7% (16 of 24) for patients with BRCA1 and BRCA2 mutations and 36.4% (44 of 121) for patients without (OR, 3.50; 95% CI, 1.39-8.84; P = .008). The high pCR rate observed in BRCA1 and BRCA2 mutation carriers (16 of 24 [66.7%]) was not increased further by adding carboplatin (17 of 26 [65.4%]). In contrast, carboplatin increased response rates in patients without BRCA1 and BRCA2 mutations: 66 of the 120 patients (55%) without BRCA1 and BRCA2 mutations achieved pCR in the carboplatin arm vs 44 of the 121 patients (36.4%) in the noncarboplatin arm (OR, 2.14; 95% CI, 1.28-3.58; P = .004). Patients without pathogenic BRCA1 and BRCA2 alterations showed elevated disease-free survival rates when carboplatin was added (without carboplatin, 73.5%; 95% CI, 64.1%-80.8% vs with carboplatin, 85.3%; 95% CI, 77.0%-90.8%; hazard ratio, 0.53; 95% CI, 0.29-0.96; P = .04). Conclusions and Relevance Under the nonstandard GeparSixto polychemotherapy regimen, patients without BRCA1 and BRCA2 germline mutations benefited from the addition of carboplatin and those with BRCA1 and BRCA2 mutations showed superior response rates without additive effects observed for carboplatin. Trial Registration clinicaltrials.gov Identifier: NCT01426880

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Sibylle Loibl

Goethe University Frankfurt

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G. von Minckwitz

Goethe University Frankfurt

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