Christian Galata
Heidelberg University
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Publication
Featured researches published by Christian Galata.
PLOS ONE | 2015
Johannes Betge; Grainne Kerr; Thilo Miersch; Svenja Leible; Gerrit Erdmann; Christian Galata; T Zhan; Timo Gaiser; Stefan Post; Matthias P. Ebert; Karoline Horisberger; Michael Boutros
Next generation sequencing (NGS) is an emerging technology becoming relevant for genotyping of clinical samples. Here, we assessed the stability of amplicon sequencing from formalin-fixed paraffin-embedded (FFPE) and paired frozen samples from colorectal cancer metastases with different analysis pipelines. 212 amplicon regions in 48 cancer related genes were sequenced with Illumina MiSeq using DNA isolated from resection specimens from 17 patients with colorectal cancer liver metastases. From ten of these patients, paired fresh frozen and routinely processed FFPE tissue was available for comparative study. Sample quality of FFPE tissues was determined by the amount of amplifiable DNA using qPCR, sequencing libraries were evaluated using Bioanalyzer. Three bioinformatic pipelines were compared for analysis of amplicon sequencing data. Selected hot spot mutations were reviewed using Sanger sequencing. In the sequenced samples from 16 patients, 29 non-synonymous coding mutations were identified in eleven genes. Most frequent were mutations in TP53 (10), APC (7), PIK3CA (3) and KRAS (2). A high concordance of FFPE and paired frozen tissue samples was observed in ten matched samples, revealing 21 identical mutation calls and only two mutations differing. Comparison of these results with two other commonly used variant calling tools, however, showed high discrepancies. Hence, amplicon sequencing can potentially be used to identify hot spot mutations in colorectal cancer metastases in frozen and FFPE tissue. However, remarkable differences exist among results of different variant calling tools, which are not only related to DNA sample quality. Our study highlights the need for standardization and benchmarking of variant calling pipelines, which will be required for translational and clinical applications.
Clinical Cancer Research | 2018
Daniela Hirsch; Darawalee Wangsa; Yuelin J. Zhu; Yue Hu; Daniel C. Edelman; Paul S. Meltzer; Kerstin Heselmeyer-Haddad; Claudia Ott; Peter Kienle; Christian Galata; Karoline Horisberger; Thomas Ried; Timo Gaiser
Purpose: Patients with inflammatory bowel diseases, that is, ulcerative colitis and Crohns disease (CD), face an increased risk of developing colorectal cancer (CRC). Evidence, mainly from ulcerative colitis, suggests that TP53 mutations represent an initial step in the progression from inflamed colonic epithelium to CRC. However, the pathways involved in the evolution of CRC in patients with CD are poorly characterized. Experimental Design: Here, we analyzed 73 tissue samples from 28 patients with CD-CRC, including precursor lesions, by targeted next-generation sequencing of 563 cancer-related genes and array-based comparative genomic hybridization. The results were compared with 24 sporadic CRCs with similar histomorphology (i.e., mucinous adenocarcinomas), and to The Cancer Genome Atlas data (TCGA). Results: CD-CRCs showed somatic copy-number alterations (SCNAs) similar to sporadic CRCs with one notable exception: the gain of 5p was significantly more prevalent in CD-CRCs. CD-CRCs had a distinct mutation signature: TP53 (76% in CD-CRCs vs. 33% in sporadic mucinous CRCs), KRAS (24% vs. 50%), APC (17% vs. 75%), and SMAD3 (3% vs. 29%). TP53 mutations and SCNAs were early and frequent events in CD progression, while APC, KRAS, and SMAD2/4 mutations occurred later. In four patients with CD-CRC, at least one mutation and/or SCNAs were already present in non-dysplastic colonic mucosa, indicating occult tumor evolution. Conclusions: Molecular profiling of CD-CRCs and precursor lesions revealed an inflammation-associated landscape of genome alterations: 5p gains and TP53 mutations occurred early in tumor development. Detection of these aberrations in precursor lesions may help predicting disease progression and distinguishes CD-associated from sporadic colorectal neoplasia. Clin Cancer Res; 24(20); 4997–5011. ©2018 AACR.
Journal of Clinical Gastroenterology | 2017
Christian Galata; Daniela Hirsch; W Reindl; Stefan Post; Peter Kienle; Michael Boutros; Timo Gaiser; Karoline Horisberger
Goals: The aim of this study was to assess the histopathologic characteristics of colorectal carcinomas (CRC) in patients with Crohn’s disease (CD). Background: A higher frequency of microsatellite instability (MSI) is seen in mucinous compared with nonmucinous CRC which suggests that its pathogenesis involves distinct molecular pathways. Several publications reported a higher percentage of mucinous adenocarcinoma in CD patients with CRC. So far, there has been no investigation of MSI in CD patients with mucinous CRC. Study: The medical records of patients who underwent surgery for CRC were reviewed and those with a history of CD identified. The data of histologic classification and MSI status of the tumor were investigated. Results: Fourteen patients with CD-associated CRC were identified (5 female, 9 male) resulting in 20 CRC in total. Histologic investigation revealed 7 adenocarcinomas without a mucinous or signet ring cell component. All other CRCs harbored a mucinous (n=11) and/or signet ring cell (n=6) component. All tumors assessed for MSI were found to be microsatellite stable. Conclusions: Our data indicate that CRCs with signet ring cell and mucinous components were much more common in patients with CD than in patients with sporadic CRC. This observation suggests that CRC in CD represent an own entity with distinct histopathologic and molecular features. This may implicate potential consequences for diagnosis and therapy of CRC in CD in the future as well as new factors to identify patients with an increased risk for developing CRC in CD.
Colorectal Disease | 2017
Hanna Elias; Christian Galata; Rene Warschkow; Bruno M. Schmied; Thomas Steffen; Stefan Post; Lukas Marti
The operative treatment for non‐metastatic appendiceal carcinoma is controversial despite the recommendation of right hemicolectomy (RH) by many researchers. The aim of this population‐based study was to compare outcomes after RH and less radical resection than right hemicolectomy (LRH).
International Journal of Surgery Case Reports | 2015
Christian Galata; Roger Vogelmann; Timo Gaiser; Stefan Post; Karoline Horisberger
Highlights • We present an uncommon case of extended abdominoplevic actinomycosis.• The patient underwent successful surgical and subsequent long-term antibiotic therapy.• The possibility of a malignant process required radical resection.• Actinomycisis should be considered when a pelvic mass is associated with use of an intrauterine device.
Journal of Surgical Oncology | 2018
Alexander Wilhelm; Christian Galata; Ulrich Beutner; Bruno M. Schmied; Rene Warschkow; Thomas Steffen; Walter Brunner; Stefan Post; Lukas Marti
This study assessed the influence of tumor localization of small bowel adenocarcinoma on survival after surgical resection.
International Journal of Colorectal Disease | 2017
Lukas Marti; Christian Galata; Ulrich Beutner; Franc H. Hetzer; Nicoletta Pipitone; Katja Wolff; Jan Borovicka; Walter Brunner; Michael C. Sulz; Christine Maurus
World Journal of Surgical Oncology | 2018
Christian Galata; Kirsten Merx; Sabine Mai; Timo Gaiser; Frederik Wenz; Stefan Post; Peter Kienle; Ralf-Dieter Hofheinz; Karoline Horisberger
Somnologie | 2018
Steffen Seyfried; Joachim T. Maurer; Christian Galata; Georgie Vassilev; Mirko Otto
International Journal of Colorectal Disease | 2018
Christian Galata; Christel Weiss; Julia Hardt; Steffen Seyfried; Stefan Post; Peter Kienle; Karoline Horisberger