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Dive into the research topics where Ahmed El-Balat is active.

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Featured researches published by Ahmed El-Balat.


PLOS ONE | 2017

Prevalence of deleterious germline variants in risk genes including BRCA1/2 in consecutive ovarian cancer patients (AGO-TR-1)

Philipp Harter; Jan Hauke; Florian Heitz; Alexander Reuss; Stefan Kommoss; Frederik Marme; André Heimbach; Katharina Prieske; Lisa Richters; Alexander Burges; Guido Neidhardt; Nikolaus de Gregorio; Ahmed El-Balat; Felix Hilpert; Werner Meier; Rainer Kimmig; Karin Kast; Jalid Sehouli; Klaus H. Baumann; Christian Jackisch; Tjoung-Won Park-Simon; Lars Hanker; Sandra Kröber; Jacobus Pfisterer; Heidrun Gevensleben; Andreas Schnelzer; Dimo Dietrich; Tanja Neunhöffer; Mathias Krockenberger; Sara Y. Brucker

Background Identification of families at risk for ovarian cancer offers the opportunity to consider prophylactic surgery thus reducing ovarian cancer mortality. So far, identification of potentially affected families in Germany was solely performed via family history and numbers of affected family members with breast or ovarian cancer. However, neither the prevalence of deleterious variants in BRCA1/2 in ovarian cancer in Germany nor the reliability of family history as trigger for genetic counselling has ever been evaluated. Methods Prospective counseling and germline testing of consecutive patients with primary diagnosis or with platinum-sensitive relapse of an invasive epithelial ovarian cancer. Testing included 25 candidate and established risk genes. Among these 25 genes, 16 genes (ATM, BRCA1, BRCA2, CDH1, CHEK2, MLH1, MSH2, MSH6, NBN, PMS2, PTEN, PALB2, RAD51C, RAD51D, STK11, TP53) were defined as established cancer risk genes. A positive family history was defined as at least one relative with breast cancer or ovarian cancer or breast cancer in personal history. Results In total, we analyzed 523 patients: 281 patients with primary diagnosis of ovarian cancer and 242 patients with relapsed disease. Median age at primary diagnosis was 58 years (range 16–93) and 406 patients (77.6%) had a high-grade serous ovarian cancer. In total, 27.9% of the patients showed at least one deleterious variant in all 25 investigated genes and 26.4% in the defined 16 risk genes. Deleterious variants were most prevalent in the BRCA1 (15.5%), BRCA2 (5.5%), RAD51C (2.5%) and PALB2 (1.1%) genes. The prevalence of deleterious variants did not differ significantly between patients at primary diagnosis and relapse. The prevalence of deleterious variants in BRCA1/2 (and in all 16 risk genes) in patients <60 years was 30.2% (33.2%) versus 10.6% (18.9%) in patients ≥60 years. Family history was positive in 43% of all patients. Patients with a positive family history had a prevalence of deleterious variants of 31.6% (36.0%) versus 11.4% (17.6%) and histologic subtype of high grade serous ovarian cancer versus other showed a prevalence of deleterious variants of 23.2% (29.1%) and 10.2% (14.8%), respectively. Testing only for BRCA1/2 would miss in our series more than 5% of the patients with a deleterious variant in established risk genes. Conclusions 26.4% of all patients harbor at least one deleterious variant in established risk genes. The threshold of 10% mutation rate which is accepted for reimbursement by health care providers in Germany was observed in all subgroups analyzed and neither age at primary diagnosis nor histo-type or family history sufficiently enough could identify a subgroup not eligible for genetic counselling and testing. Genetic testing should therefore be offered to every patient with invasive epithelial ovarian cancer and limiting testing to BRCA1/2 seems to be not sufficient.


JAMA Oncology | 2017

Association Between Genomic Metrics and Immune Infiltration in Triple-Negative Breast Cancer

Thomas Karn; Tingting Jiang; Christos Hatzis; Nicole Sänger; Ahmed El-Balat; Achim Rody; Uwe Holtrich; Sven Becker; Giampaolo Bianchini; Lajos Pusztai

Importance Why some triple-negative breast cancers (TNBCs) have high and others have low immune cell infiltration is unknown. Understanding how immune surveillance shapes the cancer genome could help in the selection of patients and the development of more effective immunotherapy strategies. Objective To examine the association between genomic metrics and the extent of immune infiltration in TNBCs. Design, Setting, and Participants This study, performed from June 1, 2015, through January 31, 2017, used DNA and RNA sequencing data and messenger RNA expression results from The Cancer Genome Atlas (TCGA) breast cancer data set (n = 1215) to calculate previously described immune metagene expression values and histologic lymphocyte counts to quantify immune infiltration and assign prognostic categories to TNBCs. It used the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) data set as an independent validation cohort. The study compared clonal heterogeneity, somatic total mutational load, neoantigen load, and somatic copy number alteration levels between immune-rich TNBC cohorts with good prognosis and immune-poor TNBC cohorts with poor prognosis. The study also compared the distribution of mutations in 119 canonical cancer genes. Main Outcomes and Measures Correlation between immune prognostic category and genomic metrics of the cancer. Results This study of 193 TNBC samples with patient survival information found an inverse association between clonal heterogeneity and immune metagene expression (&rgr; = −0.395, P = 2 × 10−8). The study also found an inverse association between immune metagene expression and somatic copy number alteration levels (&rgr; = −0.484, P = 2 × 10−10). Lymphocyte-rich TNBCs with good prognosis had significantly lower mutation and neoantigen counts than did lymphocyte-poor TNBCs with poor prognosis. The robustness of the study results was confirmed by using various immune metagenes in the same TCGA data set and in the independent METABRIC data set. Conclusions and Relevance This study suggests that immune-rich TNBCs may be under an immune surveillance that continuously eliminates many immunogenic clones, resulting in lower clonal heterogeneity. These cancers may also represent the subset of TNBCs that could derive benefit from immune checkpoint inhibitor therapy to tilt the balance in favor of the immune system.


Journal of Clinical Pathology | 2016

Fascin-1 expression as stratification marker in borderline epithelial tumours of the ovary

Ahmed El-Balat; Ruza Arsenic; Nicole Sänger; Thomas Karn; Sven Becker; Uwe Holtrich; Knut Engels

Aims To evaluate the actin-bundling protein fascin-1 (FSCN1) as marker for borderline ovarian tumours (BOTs). Methods We analysed a retrospective cohort of 140 BOTs with validated diagnosis by an independent pathologist. Immunohistochemical detection of FSCN1 was quantified as combined immunoreactive score (CIS) blinded to clinical patient data. Analyses were first performed for FSCN1 positive versus negative, and then verified using three categories derived from the observed distribution (negative, weak, strong; CIS 0, 1–2, 3–9). Results We detected FSCN1 positivity in 51.4%, and strong expression (CIS 3–9) in 14.3% of the samples. FSCN1 positivity was associated with serous subtype (p<0.001) and micropapillary pattern (p<0.001). Correlation with micropapillary pattern remained significant within the serous BOT (SBOT) subgroup (p=0.022). Strong FSCN1 expression (CIS 3–9) was associated both with the presence of implants (p=0.022), and a higher International Federation of Gynecology and Obstetrics (FIGO) stage (p=0.020). Conclusions Our analysis links FSCN1 with SBOT with micropapillary pattern. Strong expression is associated with higher FIGO stage and the presence of implants, both related to elevated risk of recurrence. Hence, FSCN1 is an interesting marker worth further analyses of its prognostic value in BOTs.


Lancet Oncology | 2018

Sorafenib plus topotecan versus placebo plus topotecan for platinum-resistant ovarian cancer (TRIAS): a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial

Radoslav Chekerov; Felix Hilpert; Sven Mahner; Ahmed El-Balat; Philipp Harter; Nikolaus de Gregorio; Claudius Fridrich; Susanne Markmann; Jochem Potenberg; Ralf Lorenz; Guelten Oskay-Oezcelik; Marcus Schmidt; Petra Krabisch; Hans-Joachim Lueck; R. Richter; Elena Ioana Braicu; Andreas du Bois; Jalid Sehouli; W. Lichtenegger; Isil Yalcinkaya; Marion Kittner; Ellen Konwert; Maren Keller; Alexander Mustea; Dominique Koensgen-Mustea; Klaus Pietzner; Oumar Camara; Pauline Wimberger; G. Elser; Sandra Polleis

BACKGROUND Antiangiogenic therapy has known activity in ovarian cancer. The investigator-initiated randomised phase 2 TRIAS trial assessed the multi-kinase inhibitor sorafenib combined with topotecan and continued as maintenance therapy for platinum-resistant or platinum-refractory ovarian cancer. METHODS We did a multicentre, double-blind, placebo-controlled, randomised, phase 2 trial at 20 sites in Germany. Patients (≥18 years) with platinum-resistant ovarian cancer previously treated with two or fewer chemotherapy lines for recurrent disease were stratified (first vs later relapse) in block sizes of four and randomly assigned (1:1) using a web-generated response system to topotecan (1·25 mg/m2 on days 1-5) plus either oral sorafenib 400 mg or placebo twice daily on days 6-15, repeated every 21 days for six cycles, followed by daily maintenance sorafenib or placebo for up to 1 year in patients without progression. Investigators and patients were masked to allocation of sorafenib or placebo; topotecan treatment was open label. The primary endpoint was investigator-assessed progression-free survival, analysed in all patients who received at least one dose of study drug. This completed trial is registered with ClinicalTrials.gov, number NCT01047891. FINDINGS Between Jan 18, 2010, and Sept 19, 2013, 185 patients were enrolled, 174 of whom were randomly assigned: 85 to sorafenib and 89 to placebo. Two patients in the sorafenib group had serious adverse events before treatment and were excluded from analyses. 83 patients in the sorafenib group and 89 in the placebo group started treatment. Progression-free survival was significantly improved with sorafenib versus placebo (hazard ratio 0·60, 95% CI 0·43-0·83; p=0·0018). Median progression-free survival was 6·7 months (95% CI 5·8-7·6) with sorafenib versus 4·4 months (3·7-5·0) with placebo. The most common grade 3-4 adverse events were leucopenia (57 [69%] of 83 patients in the sorafenib group vs 47 [53%] of 89 in the placebo group), neutropenia (46 [55%] vs 48 [54%]), and thrombocytopenia (23 [28%] vs 20 [22%]). Serious adverse events occurred in 49 (59%) of 83 sorafenib-treated patients and 45 (51%) of 89 placebo-treated patients. Of these, events were fatal in four patients (5%) in the sorafenib group (dyspnoea and poor general condition, septic shock, ascites and dyspnoea, and sigma perforation) and seven (8%) in the placebo group (pulmonary embolism in two patients, disease progression in two patients, and one case each of sepsis with fever, pleural effusion, and tumour cachexia). Sorafenib was associated with increased incidences of grade 3 hand-foot skin reaction (three [13%] vs 0 patients) and grade 2 alopecia (24 [29%] vs 12 [13%]). INTERPRETATION Sorafenib, when given orally in combination with topotecan and continued as maintenance therapy, showed a statistically and clinically significant improvement in progression-free survival in women with platinum-resistant ovarian cancer. These encouraging results support the crucial role of antiangiogenesis as the treatment backbone in combination with chemotherapy, making this approach attractive for further assessment with other targeted strategies. FUNDING Bayer, Amgen, and GlaxoSmithKline.


in Vivo | 2018

Catheter-related Complications of Subcutaneous Implantable Venous Access Devices in Breast Cancer Patients

Ahmed El-Balat; Iryna Schmeil; Thomas Karn; Uwe Holtrich; Loreta Mavrova-Risteska; Achim Rody; Aly Youssef; Lars Hanker

Background/Aim: Totally implanted venous access devices (TIVAD) are increasingly used in the treatment of cancer patients. The aim of this study was to assess the incidence of early and late complications resulting from subcutaneous TIVADs in patients with breast cancer. Materials and Methods: Between 2004 and 2009, we reviewed patients with breast cancer who had a TIVAD placed. Early and late complications, as well as risk factors for TIVAD-associated thrombosis were retrospectively assessed. Results: A total of 281 patients were included. Complications occurred in 26% of patients, the majority of which were late complications (21.4%.) The development of TIVAD associated thrombosis was the most frequent late complication (16.4%). In the univariate analysis followed by a multivariate model, risk factors for TIVAD associated thrombosis were not identified. Only within the subgroup of metastatic breast cancer patients an increased risk of TIVAD-associated thrombosis of left compared to right venous access was detected (p=0.015). Conclusion: TIVAD implantation done in a gynecological outpatient setting is feasible and safe.


Oncotarget | 2018

Synthetic lethality in CCNE1 -amplified high grade serous ovarian cancer through combined inhibition of polo-like kinase 1 and microtubule dynamics

Sabrina Noack; Monika Raab; Yves Matthess; Mourad Sanhaji; Andrea Krämer; Balázs Győrffy; Lars Kaderali; Ahmed El-Balat; Sven Becker; Klaus Strebhardt

The taxanes are effective microtubule-stabilizing chemotherapy drugs that inhibit mitosis, induce apoptosis, and produce regression in a fraction of cancers that arise at many sites including the ovary. Novel therapeutic targets that augment taxane effects are needed to improve clinical chemotherapy response in CCNE1-amplified high grade serous ovarian cancer (HGSOC) cells. In this study, we conducted an siRNA-based kinome screen to identify modulators of mitotic progression in CCNE1-amplified HGSOC cells that may influence clinical paclitaxel response. PLK1 is overexpressed in many types of cancer, which correlates with poor prognosis. Here, we identified a novel synthetic lethal interaction of the clinical PLK1 inhibitor BI6727 and the microtubule-targeting drug paclitaxel in HGSOC cell lines with CCNE1-amplification and elucidated the underlying molecular mechanisms of this synergism. BI6727 synergistically induces apoptosis together with paclitaxel in different cell lines including a patient-derived primary ovarian cancer culture. Moreover, the inhibition of PLK1 reduced the paclitaxel-induced neurotoxicity in a neurite outgrowth assay. Mechanistically, the combinatorial treatment with BI6727/paclitaxel triggers mitotic arrest, which initiates mitochondrial apoptosis by inactivation of anti-apoptotic BCL-2 family proteins, followed by significant loss of the mitochondrial membrane potential and activation of caspase-dependent effector pathways. This conclusion is supported by data showing that BI6727/paclitaxel-co-treatment stabilizes FBW7, a component of SCF-type ubiquitin ligases that bind and regulate key modulators of cell division and growth including MCL-1 and Cyclin E. This identification of a novel synthetic lethality of PLK1 inhibitors and a microtubule-stabilizing drug has important implications for developing PLK1 inhibitor-based combination treatments in CCNE1-amplified HGSOC cells.


Journal of Clinical Pathology | 2018

Claudin-1 is linked to presence of implants and micropapillary pattern in serous borderline epithelial tumours of the ovary

Ahmed El-Balat; Iryna Schmeil; Khayal Gasimli; Nicole Sänger; Thomas Karn; Andre Ahr; Sven Becker; Ruza Arsenic; Uwe Holtrich; Knut Engels

Aims Expression of Claudin-1 has been associated with prognosis in several cancers. Here we investigated the expression pattern of Claudin-1 in borderline tumours of the ovary (BOT). Methods We analysed a cohort of 114 cases of borderline tumour (BOT). Claudin-1 expression was studied by immunohistochemistry using a polyclonal antibody and was compared with clinical and histopathological characteristics. Results Strong Claudin-1 expression was found in 30 cases (26.3%) independent of histological subtype. Expression was significantly less frequent in International Federation of Gynecology and Obstetrics (FIGO) stage I (p= 0.045), while the presence of microinvasion did not correlate with Claudin-1 expression. In contrast, we detected a highly significant association of Claudin-1 expression with the presence of peritoneal implants (p=0.003) and micropapillary pattern (p=0.047), which are features exclusively seen in serous BOT. Moreover, when we restricted our analysis to the subtype of serous BOT, the association of Claudin-1 expression with peritoneal implants (p<0.001) and micropapillary pattern (p =0.003) remained highly significant. Conclusions In conclusion, Claudin-1 expression is associated with the presence of peritoneal implants and micropapillary pattern, which have been shown to be associated with poor prognosis. We speculate that overexpression of Claudin-1 might be linked to the mitogen-activated protein kinase pathway activation in BOT and suggest further studies to define its prognostic and potential therapeutic value.


BioMed Research International | 2018

Modern Myoma Treatment in the Last 20 Years: A Review of the Literature

Ahmed El-Balat; Rudy Leon DeWilde; Iryna Schmeil; Morva Tahmasbi-Rad; Sandra Bogdanyova; Ali Fathi; Sven Becker

Myomas, also known as fibroids, are a specific characteristic of the human species. No other primates develop fibroids. At a cellular level, myomas are benign hyperplastic lesions of uterine smooth muscle cells. There are interesting theoretical concepts that link the development of myomas in humans with the highly specific process of childbirth from an upright position and the resulting need for greatly increased “expulsive” forces during labor. Myomas might be the price our species pays for our bipedal and highly intelligent existence. Myomas affect, with some variability, all ethnic groups and approximately 50% of all women during their lifetime. While some remain asymptomatic, myomas can cause significant and sometimes life-threatening uterine bleeding, pain, infertility, and, in extreme cases, ureteral obstruction and death. Traditionally, over 50% of all hysterectomies were performed for fibroids, leading to a significant healthcare burden. In this article, we review the developments of the past 20 years with regard to multiple new treatment strategies that have evolved during this time.


Gynakologe | 2017

Epidemiologie und Pathologie des Vulvakarzinoms

Ahmed El-Balat; Iryna Schmeil; Morva Tahmasbi-Rad; Sven Becker

ZusammenfassungDargestellt wird die aktuelle Datenlage bezüglich epidemiologischer Beobachtungen und ätiologischer Faktoren für die unterschiedlichen Vulvamalignome. Das Wissen um die Epidemiologie, die Pathogenese und die ätiologischen Faktoren des Vulvakarzinoms ist nicht nur relevant für Präventionsstrategien, Früherkennungsmaßnahmen, die Implementierung von Screnningprogrammen und für therapeutische Entscheidungen, sondern auch für das postoperative Management im Sinne der Risikostratifizierung. Skizziert wird auch das beginnende Verständnis der molekularbiologischen Pathways. Die weitere Forschung kann künftig eine dezidiert neue Systematisierung der nosologischen Subentitäten initiieren, ferner möglicherweise auch innovative therapeutische Ansätze und Strategien ermöglichen.AbstractThis article presents the current situation with respect to epidemiological observations and etiological factors for the various malignant vulvar tumors. Knowledge of the epidemiology, pathogenesis and etiological factors of vulvar cancer is not only relevant for preventive strategies, measures for early recognition, implementation of screening programs and therapeutic decisions but also for postoperative management in the sense of risk stratification. The initial understanding of the molecular biological pathways is also outlined. Further research can in the future initiate a decidedly novel systematization of nosological subentities and possibly also enable innovative therapeutic approaches and strategies.


Archives of Gynecology and Obstetrics | 2015

Systematic pelvic and paraaortic lymphadenectomy in early high-risk or advanced endometrial cancer

Christina Fotopoulou; Ahmed El-Balat; Andreas du Bois; Jalid Sehouli; Philipp Harter; Mustafa Zelal Muallem; Robert W. Krätschell; Alexander Traut; Florian Heitz

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Sven Becker

University of Tübingen

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Thomas Karn

Goethe University Frankfurt

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Florian Heitz

University of Duisburg-Essen

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Iryna Schmeil

Goethe University Frankfurt

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Uwe Holtrich

Goethe University Frankfurt

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Nicole Sänger

Goethe University Frankfurt

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Philipp Harter

University of Duisburg-Essen

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Jan Hauke

University of Cologne

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