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Featured researches published by Hans Bojar.


Clinical Cancer Research | 2012

A Comprehensive Analysis of Human Gene Expression Profiles Identifies Stromal Immunoglobulin κ C as a Compatible Prognostic Marker in Human Solid Tumors

Marcus Schmidt; Birte Hellwig; Seddik Hammad; Amnah Othman; Miriam Lohr; Zonglin Chen; Daniel Boehm; Susanne Gebhard; Ilka Brigitte Petry; Antje Lebrecht; Cristina Cadenas; Rosemarie Marchan; Joanna D. Stewart; Christine Solbach; Lars Holmberg; Karolina Edlund; Hanna Göransson Kultima; Achim Rody; Anders Berglund; Mats Lambe; Anders Isaksson; Johan Botling; Thomas Karn; Volkmar Müller; Aslihan Gerhold-Ay; Christina Cotarelo; Martin Sebastian; Ralf Kronenwett; Hans Bojar; Hans A. Lehr

Purpose: Although the central role of the immune system for tumor prognosis is generally accepted, a single robust marker is not yet available. Experimental Design: On the basis of receiver operating characteristic analyses, robust markers were identified from a 60-gene B cell–derived metagene and analyzed in gene expression profiles of 1,810 breast cancer; 1,056 non–small cell lung carcinoma (NSCLC); 513 colorectal; and 426 ovarian cancer patients. Protein and RNA levels were examined in paraffin-embedded tissue of 330 breast cancer patients. The cell types were identified with immunohistochemical costaining and confocal fluorescence microscopy. Results: We identified immunoglobulin κ C (IGKC) which as a single marker is similarly predictive and prognostic as the entire B-cell metagene. IGKC was consistently associated with metastasis-free survival across different molecular subtypes in node-negative breast cancer (n = 965) and predicted response to anthracycline-based neoadjuvant chemotherapy (n = 845; P < 0.001). In addition, IGKC gene expression was prognostic in NSCLC and colorectal cancer. No association was observed in ovarian cancer. IGKC protein expression was significantly associated with survival in paraffin-embedded tissues of 330 breast cancer patients. Tumor-infiltrating plasma cells were identified as the source of IGKC expression. Conclusion: Our findings provide IGKC as a novel diagnostic marker for risk stratification in human cancer and support concepts to exploit the humoral immune response for anticancer therapy. It could be validated in several independent cohorts and carried out similarly well in RNA from fresh frozen as well as from paraffin tissue and on protein level by immunostaining. Clin Cancer Res; 18(9); 2695–703. ©2012 AACR.


Clinical Cancer Research | 2004

Identifying superficial, muscle-invasive, and metastasizing transitional cell carcinoma of the bladder: Use of cDNA array analysis of gene expression profiles

Olga Modlich; Hans-Bernd Prisack; Gerald Pitschke; Uwe Ramp; Rolf Ackermann; Hans Bojar; Thomas A. Vögeli; Marc-Oliver Grimm

Purpose: Expression profiling by DNA microarray technology permits the identification of genes underlying clinical heterogeneity of bladder cancer and which might contribute to disease progression, thereby improving assessment of treatment and prediction of patient outcome. Experimental Design: Invasive (20) and superficial (22) human bladder tumors from 34 patients with known outcome regarding disease recurrence and progression were analyzed by filter-based cDNA arrays (Atlas Human Cancer 1.2; BD Biosciences Clontech) containing 1185 genes. For 9 genes, array data were confirmed using real-time reverse transcription-PCR. Additionally, Atlas array data were validated using Affymetrix GeneChip oligonucleotide arrays with 22,283 human gene fragments and expressed sequence tags sequences in a subset of three superficial and six invasive bladder tumors. Results: A two-way clustering algorithm using different subsets of gene expression data, including a subset of 41 genes validated by the oligonucleotide array (Affymetrix), classified tumor samples according to clinical outcome as superficial, invasive, or metastasizing. Furthermore, (a) a clonal origin of superficial tumors, (b) highly similar gene expression patterns in different areas of invasive tumors, and (c) an invasive-like pattern was observed in bladder mucosas derived from patients with locally advanced disease. Several gene clusters that characterized invasive or superficial tumors were identified. In superficial bladder tumors, increased mRNA levels of genes encoding transcription factors, molecules involved in protein synthesis and metabolism, and some proteins involved into cell cycle progression and differentiation were observed, whereas transcripts for immune, extracellular matrix, adhesion, peritumoral stroma and muscle tissue components, proliferation, and cell cycle controllers were up-regulated in invasive tumors. Conclusions: Gene expression profiling of human bladder cancers provides insight into the biology of bladder cancer progression and identifies patients with distinct clinical phenotypes.


Journal of Clinical Oncology | 1994

Randomized 2 x 2 trial evaluating hormonal treatment and the duration of chemotherapy in node-positive breast cancer patients. German Breast Cancer Study Group.

Martin Schumacher; G Bastert; Hans Bojar; K Hübner; M Olschewski; Willi Sauerbrei; Claudia Schmoor; C. Beyerle; R. L. A. Neumann; H F Rauschecker

PURPOSE In 1984, the German Breast Cancer Study Group (GBSG) started a multicenter randomized clinical trial to compare the effectiveness of three versus six cycles of 500 mg/m2 cyclophosphamide, 40 mg/m2 methotrexate, and 600 mg/m2 fluorouracil (CMF) on day 1 and 8 starting perioperatively with or without tamoxifen (TAM) (3 x 10 mg/d for 2 years). The aim of the trial was to compare recurrence-free and overall survival between the different treatment modalities. PATIENTS AND METHODS During 5 years, 41 institutions randomized 473 patients (3 x CMF: 145; 3 x CMF + TAM: 93; 6 x CMF 144; 6 x CMF + TAM: 91). Until March 31, 1992, median follow-up time was 56 months with 197 events for disease-free survival and 116 deaths observed. This provides a power of approximately 80% to detect a potential treatment difference corresponding to a relative risk (RR) of 0.67 for recurrence-free survival. Treatment modalities and various patient characteristics were evaluated by means of a multivariate Cox regression analysis. RESULTS No significant difference in recurrence-free survival was observed with respect to hormonal therapy (RR = 0.75 TAM v no TAM; 95% confidence interval [CI], 0.54 to 1.04; P = .08) as well as duration of chemotherapy (RR = 0.90 of 6 x CMF v 3 x CMF; 95% CI, 0.67 to 1.19; P = .45). Similar results were obtained for overall survival. The multivariate analysis revealed a significant prognostic impact of the number of positive lymph nodes and the progesterone receptor level on recurrence-free survival. Compliance with chemotherapy within the range of 85% to 115% of the target dose was achieved in 94% and 78% of the patients randomized to 3 x CMF and 6 x CMF, respectively. Sufficient compliance with TAM was reported for 141 patients (93%). CONCLUSION At this stage of follow-up, six courses of CMF are not superior to three courses with respect to recurrence-free survival.


British Journal of Cancer | 1999

Modelling the effects of standard prognostic factors in node-positive breast cancer

Willi Sauerbrei; Patrick Royston; Hans Bojar; Claudia Schmoor; Martin Schumacher

SummaryPrognostic models that predict the clinical course of a breast cancer patient are important in oncology. We propose an approach to constructing such models based on fractional polynomials in which useful transformations of the continuous factors are determined. The idea may be applied with all types of regression model, including Cox regression, the method of choice for survival-time data. We analyse a prospective study of node-positive breast cancer. Seven standard prognostic factors – age, menopausal status, tumour size, tumour grade, number of positive lymph nodes, progesterone and oestrogen receptor concentrations – were investigated in 686 patients, of whom 299 had an event for recurrence-free survival and 171 died. We determine a final model with transformations of prognostic factors and compare it with the more traditional approaches using categorized variables or assuming a straight line relationship. We conclude that analysis using fractional polynomials can extract important prognostic information which the traditional approaches may miss.


Clinical Cancer Research | 2004

Immediate Gene Expression Changes After the First Course of Neoadjuvant Chemotherapy in Patients with Primary Breast Cancer Disease

Olga Modlich; Hans-Bernd Prisack; Marc Munnes; Werner Audretsch; Hans Bojar

Purpose: Our goal was to identify genes undergoing expressional changes shortly after the beginning of neoadjuvant chemotherapy for primary breast cancer. Experimental Design: The biopsies were taken from patients with primary breast cancer prior to any treatment and 24 hours after the beginning of the neoadjuvant chemotherapy. Expression analyses from matched pair samples representing 25 patients were carried out with Clontech filter arrays. A subcohort of those 25 paired samples were additionally analyzed with the Affymetrix GeneChip platform. All of the transcripts from both platforms were queried for expressional changes. Results: Performing hierarchical cluster analysis, we clustered pre- and posttreatment samples from individual patients more closely to each other than the samples taken from different patients. This reflects the rather low number of transcripts responding directly to the drugs used. Although transcriptional drug response occurring during therapy differed between individual patients, two genes (p21WAF1/CIP1 and MIC-1) were up-regulated in posttreatment samples. This could be validated by semiquantitative and real-time reverse transcription-PCR. Partial least- discriminant analysis based on approximately 25 genes independently identified by either Clontech or Affymetrix platforms could clearly discriminate pre- and posttreatment samples. However, correlation of certain gene expression levels as well as of differential patterns and clusters as determined by a different platform was not always satisfying. Conclusions: This study has demonstrated the potential of monitoring posttreatment changes in gene expression as a measure of the pharmacodynamics of drugs. As a clinical laboratory model, it can be useful to identify patients with sensitive and reactive tumors and to help for optimized choice for sequential therapy and obviously improve relapse- free and overall survival.


Cancer Gene Therapy | 2001

Local inflammation and devascularization — in vivo mechanisms of the “bystander effect” in VPC-mediated HSV-Tk/GCV gene therapy for human malignant glioma

Frank Floeth; Nick Shand; Hans Bojar; Hans Bernd Prisack; Jörg Felsberg; Eva Neuen-Jacob; Albrecht Aulich; Klaus J Burger; Wolfgang J. Bock; Friedrich Weber

Somatic gene therapy with the herpes simplex virus type I thymidine kinase gene/ganciclovir (HSV-Tk/GCV) system and murine retroviral vector producer cells (VPCs) was introduced as a new adjuvant treatment modality to treat tumor bulk and to prevent tumor recurrence in patients harboring malignant glioma. The single-center experience after treatment of 27 patients undergoing tumor resection followed by intracerebral VPC injection for HSV-Tk suicide gene therapy will be presented focused on findings of systematic and close MRI follow-up and a few histological specimens. The data indicate that hemorrhagic necrosis due to endothelial cell transfection mediated vessel necrosis and that local inflammatory immune response occurs frequently after gene therapy. These phenomena seem to be specific because none of the patients of a control group showed any similar features. The prognosis (time to progression, survival) of the patients with “bystander effects” after gene therapy was better, but compared to those patients without bystander effects, they were also privileged by a favorable constellation of prognostic factors. Therefore, the appearance of these neuroradiologic features cannot serve as an indicator for treatment effectiveness and outcome. Cancer Gene Therapy (2001) 8, 843–851


European Journal of Medical Research | 2010

Methylated APC and GSTP1 genes in serum DNA correlate with the presence of circulating blood tumor cells and are associated with a more aggressive and advanced breast cancer disease.

Christiane Matuschek; Edwin Bölke; Guido Lammering; Peter Arne Gerber; Matthias Peiper; Wilfried Budach; H. Taskin; Hans Bernd Prisack; Gisela Schieren; Klaus Orth; Hans Bojar

BackgroundTumor-related methylated DNA and circulating tumor cells (CTC) in the peripheral blood might be of prognostic importance in breast cancer. Thus, the aim of our study was to examine free methylated DNA and CTC in the blood from breast cancer patients and to correlate it with clinicopathological features known to influence prognosis.Materials and methodsWe prospectively obtained serum samples from 85 patients with breast cancer and 22 healthy volunteers. Sera were analysed by methylation specific PCR (MethyLight PCR) for five genes: adenomatous polyposis coli (APC), ras association domain family protein 1A (RASSF1A), estrogen receptor 1 (ESR1), CDKN2A (p16) and glutathione s-transferase pi 1 (GSTP1). Beta actin (ACTB) served as control. In parallel matched peripheral blood of 63 patients was used to assay for circulating tumor cells in the peripheral blood by a modified immunomagnetic AdnaTest BreastCancerSelect with PCR detection for EPCAM, MUC1, MGB1 and SPDEF.ResultsWe found a hypermethylation in the APC gene in 29% (25/85), in RASSF1A in 26% (22/85), in GSTP1 in 18% (14/76) and in ESR1 in 38% (32/85) of all breast cancer patients. No hypermethylation of CDKN2A was found (0/25). Blood samples of patients were defined CTC positive by detecting the EPCAM 13% (8/63), MUC1 16% (10/63), MGB 9% (5/55), SPDEF 12% (7/58) and in 27% detecting one or more genes (15/55). A significant difference was seen in methylated APC DNA between cancer patients and healthy volunteers. Moreover, methylated APC, RASSF1 and CTC were significantly different in metastatic versus non-metastatic disease. In addition, the presence of methylated APC, RASSF1A and CTC correlated significantly with AJCC-staging (p = 0.001, p = 0.031 and 0.002, respectively). High incidences of methylations were found for the genes RASSF1 and ESR1 in healthy individuals (both 23% 5/22). Methylated GSTP1 was predominantly found in the serum of patients with large primaries (p = 0.023) and was highly significantly correlated with positive Her2/neu status (p = 0.003). Elevated serum CA15.3 was strongly correlated with methylated APC and CTC detection (both p = 0.000). Methylated ESR1 failed to exhibit significant correlations with any of the above mentioned parameters. The presence of CTC in peripheral blood was significantly associated with methylated APC (p = 0.012) and methylated GSTP1 (p = 0.001).ConclusionThe detection of methylated APC and GSTP1 DNA in serum correlated with the presence of CTC in the blood of breast cancer patients. Both methylated DNA and CTC correlated with a more aggressive tumor biology and advanced disease.


European Journal of Cancer | 2001

Long-term prognosis of breast cancer patients with 10 or more positive lymph nodes treated with CMF

Claudia Schmoor; Willi Sauerbrei; G. Bastert; Hans Bojar; Martin Schumacher

The purpose of this investigation was to study the long-term prognosis of breast cancer patients with 10 or more positive lymph nodes after conventional chemotherapy treatment with cyclophosphamide, methotrexate and 5-fluorouracil (CMF). Between 1984 and 1989, 1048 node-positive patients were treated with CMF in two separate trials conducted by the German Breast Cancer Study Group (GBSG). Subgroups either received radiotherapy or tamoxifen in addition. In this study, long-term prognosis in the subgroup of 141 patients with 10 or more positive lymph nodes was investigated. Univariate and multivariate Cox models were used to evaluate the effect of prognostic factors on event-free survival (EFS) and overall survival (OS). Both univariate and multivariate analyses revealed the progesterone receptor (PR) status as the dominating prognostic factor for both EFS and OS, resulting in a strongly increased risk of more than 2-fold for receptor-negative patients. A large number of positive lymph nodes also affected the prognosis for EFS. In univariate analysis, the degree of lymph node involvement (i.e. percentage of positive nodes out of all examined nodes), oestrogen status (ER) status, and tumour grade also showed significant effects. To conclude, the prognosis in the subgroup of patients with 10 or more positive lymph nodes is heterogeneous. Some surprisingly high survival rates have been observed in case series of breast cancer patients treated with high-dose chemotherapy which may be explained by patient selection. From the usual factors investigated in this study, the PR status showed the strongest effect, and, at least this factor should be taken into account in the design and analysis of trials for breast cancer patients with a poor prognosis.


Journal of Clinical Oncology | 2000

Randomized 2 × 2 Trial Evaluating Hormonal Treatment and the Duration of Chemotherapy in Node-Positive Breast Cancer Patients: An Update Based on 10 Years’ Follow-Up

Willi Sauerbrei; G. Bastert; Hans Bojar; C. Beyerle; R. L. A. Neumann; Claudia Schmoor; Martin Schumacher

PURPOSE In 1984, the German Breast Cancer Study Group started a multicenter randomized trial to compare six versus three cycles of cyclophosphamide, methotrexate, and fluorouracil (CMF) starting perioperatively and to investigate the additional effect of tamoxifen as adjuvant treatment in node-positive breast cancer patients treated with mastectomy. PATIENTS AND METHODS From 1984 to 1989, 473 patients were randomized from 41 institutions. After a median follow-up of approximately 10 years for overall survival (OS) and 9 years for event-free survival (EFS), the treatment groups were compared with respect to OS and EFS. Results based on a median follow-up of 56 months have been published earlier. RESULTS Estimated cumulative locoregional incidence rate after 10 years was 19.9%; the corresponding rate of distant recurrences was 41.3%. Concerning duration of chemotherapy, we did not find any difference between six and three cycles of CMF (EFS: relative risk [RR] in multivariate analysis = 0.95; 95% confidence interval [CI], 0.74 to 1.21 OS: RR = 0.90; 95% CI, = 0.69 to 1.18). Treatment with tamoxifen resulted in an improvement in outcome (EFS: RR = 0.81; 95% CI, 0.61 to 1.07, OS: RR = 0.74; 95% CI, 0.55 to 1.0) although it proved not significant. Number of positive lymph nodes and progesterone receptor were the dominant prognostic factors. CONCLUSION In this study, we observed some tendency in favor of hormonal treatment, which is in agreement with the literature. Concerning duration of chemotherapy, the results of this study provide further evidence that a reduction to three cycles of CMF is possible without increasing the risk of recurrence or death. For a definitive conclusion, however, further investigations are required.


Journal of Translational Medicine | 2006

Gene expression in acute Stanford type A dissection: a comparative microarray study

Barbara Theresia Weis-Müller; Olga Modlich; Irina Drobinskaya; Derya Unay; Rita Huber; Hans Bojar; Jochen D. Schipke; Peter Feindt; Emmeran Gams; Wolfram Müller; Timm O. Goecke; W. Sandmann

BackgroundWe compared gene expression profiles in acutely dissected aorta with those in normal control aorta.Materials and methodsAscending aorta specimen from patients with an acute Stanford A-dissection were taken during surgery and compared with those from normal ascending aorta from multiorgan donors using the BD Atlas™ Human1.2 Array I, BD Atlas™ Human Cardiovascular Array and the Affymetrix HG-U133A GeneChip®. For analysis only genes with strong signals of more than 70 percent of the mean signal of all spots on the array were accepted as being expressed. Quantitative real-time polymerase chain reaction (RT-PCR) was used to confirm regulation of expression of a subset of 24 genes known to be involved in aortic structure and function.ResultsAccording to our definition expression profiling of aorta tissue specimens revealed an expression of 19.1% to 23.5% of the genes listed on the arrays. Of those 15.7% to 28.9% were differently expressed in dissected and control aorta specimens. Several genes that encode for extracellular matrix components such as collagen IV α2 and -α5, collagen VI α3, collagen XIV α1, collagen XVIII α1 and elastin were down-regulated in aortic dissection, whereas levels of matrix metalloproteinases-11, -14 and -19 were increased. Some genes coding for cell to cell adhesion, cell to matrix signaling (e.g., polycystin1 and -2), cytoskeleton, as well as several myofibrillar genes (e.g., α-actinin, tropomyosin, gelsolin) were found to be down-regulated. Not surprisingly, some genes associated with chronic inflammation such as interleukin -2, -6 and -8, were up-regulated in dissection.ConclusionOur results demonstrate the complexity of the dissecting process on a molecular level. Genes coding for the integrity and strength of the aortic wall were down-regulated whereas components of inflammatory response were up-regulated. Altered patterns of gene expression indicate a pre-existing structural failure, which is probably a consequence of insufficient remodeling of the aortic wall resulting in further aortic dissection.

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Wilfried Budach

University of Düsseldorf

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Matthias Peiper

University of Düsseldorf

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Olga Modlich

University of Düsseldorf

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Stephan Roth

University of Düsseldorf

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