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Background: Gastric cancer is the fourth most common cancer and the second leading cause of cancer death worldwide. In order to understand the genetic background, we sequenced the whole exome and the whole genome of one microsatellite stable as well as one microsatellite unstable tumor and the matched healthy tissue on two different NGS platforms. We here aimed to provide a comparative approach for individual clinical tumor sequencing and annotation using different sequencing technologies and mutation calling algorithms., Results: We applied a population-based whole genome resource as a novel pathway-based filter for interpretation of genomic alterations from single nucleotide variations (SNV), indels, and large structural variations. In addition to a comparison with tumor genome database resources and a filtering approach using data from the 1000 Genomes Project, we performed pyrosequencing analysis and immunohistochemistry in a large cohort of 428 independent gastric cancer cases., Conclusion: We here provide an example comparing the usefulness and potential pitfalls of different technologies for a clinical interpretation of genomic sequence data of individual gastric cancer samples. Using different filtering approaches, we identified a multitude of novel potentially damaging mutations and could show a validated association between a mutation in GNAS and gastric cancer.

Background: Breast cancer screening programs have been established worldwide and early detection of breast cancer has increased steadily. The most common way to confirm dignity of non-palpable and sonographically-occult suspicious findings on mammography is the stereotactically-guided vacuum-assisted breast biopsy, Purpose: To compare two stereotactically guided vacuum-assisted breast biopsy systems measuring time effectiveness and quality of harvested material in clinical practice., Material and Methods: One hundred and forty-six patients presenting with suspicious microcalcifications on mammography were included in the study. Biopsies were carried out with either the Mammotome(®) system (11-gauge and 8-gauge) or the ATEC(®) system (12-gauge and 9-gauge). Lesions with a diameter <15 mm on mammography were biopsied with 11-gauge or 12-gauge devices whereas lesions >15 mm were targeted with 8-gauge and 9-gauge. Mammotome(®) system 8-gauge device was used in 34 patients, the 11-gauge system in 37 patients. The ATEC(®) system 9-gauge system was used in 37 patients and 12-gauge in 38 patients. Time was taken, focusing on preparing the system, time of collecting the samples, preparing the samples, and cleaning the site. During the biopsies 24 samples were taken. The histologic quality of the tissue samples was judged by a pathologist in a blinded fashion according to a specimen grading classification concerning tissue fragmentation, artefacts, and the adequacy of the tissue for diagnosis., Results: The median overall time for the Mammotome(®) system was 879 s (11-gauge) and 934 s (8-gauge) and for the ATEC(®) system 671 s (12-gauge) and 673 s (9-gauge). The ATEC(®) system displays a significantly shorter overall time for small and large biopsy devices (U-test, P < 0.001). Concerning the mean time difference of the overall time comparing small and large systems the ATEC(®) system was 267.6 s faster using the small and 244.8 s faster using the large system. Comparing the histologic quality of tissue samples the Mammotome(®) system shows significantly higher values for the large and the small system (Chi-square test, P < 0.001)., Conclusion: Both biopsy systems meet all requirements for daily practice and confirm the diagnosis of suspicious microcalcifications. The ATEC(®) system was observed to be faster but this difference of about 250 s might not be relevant in daily practice. The Mammotome(®) system provides a better histologic quality of tissue samples.

Gastric cancer (GC) is one of the most common causes of cancer-related deaths worldwide. We investigated the differential expression and putative tumor biological significance of five G-protein-coupled receptors (GPCRs) in GC, i.e., LGR4, LGR6, GPR34, GPR160, and GPR171. Based on our previous microarray analyses, we identified five candidate genes in human GC samples. Real-time RT-PCR was carried out to validate their expression in malignant and non-malignant tissues on an independent collective comprising 32 GC patients with and without lymph node metastases. Selected protein targets LGR4 and LGR6 were further validated on paraffin-embedded sections of ten intestinal and ten poorly cohesive (diffuse)-type GCs and their corresponding non-malignant tissue using immunohistochemistry. Additionally, the putative tumor biological significance of LGR4 and LGR6 was studied using tissue microarrays obtained from a cohort of 481 GC patients. On transcriptional level, GPR34, GPR160, and GPR171 were not differentially expressed in GC compared with non-neoplastic mucosa. LGR4 and LGR6 were up-regulated on transcriptional (real-time RT-PCR) and translational (immunohistochemistry) levels in GC. Furthermore, in tissue microarray analysis, LGR6 expression was significantly associated with local tumor growth (T-category; p = 0.04) and correlated with patient survival. LGR4 expression was significantly correlated with nodal spread (N-category; p = 0.025). Our systematic analysis indicates that LGR4 and LGR6 may play a role in GC biology. Future studies will have to demonstrate whether these are also putative diagnostic, prognostic, and/or therapeutic targets for GC.

In this study we tested the prevalence, histoanatomical distribution and tumour biological significance of the Wnt target protein and cancer stem cell marker LGR5 in tumours of the human gastrointestinal tract. Differential expression of LGR5 was studied on transcriptional (real-time polymerase chain reaction) and translational level (immunohistochemistry) in malignant and corresponding non-malignant tissues of 127 patients comprising six different primary tumour sites, i.e. oesophagus, stomach, liver, pancreas, colon and rectum. The clinico-pathological significance of LGR5 expression was studied in 100 patients with gastric carcinoma (GC). Non-neoplastic tissue usually harboured only very few scattered LGR5(+) cells. The corresponding carcinomas of the oesophagus, stomach, liver, pancreas, colon and rectum showed significantly more LGR5(+) cells as well as significantly higher levels of LGR5-mRNA compared with the corresponding non-neoplastic tissue. Double staining experiments revealed a coexpression of LGR5 with the putative stem cell markers CD44, Musashi-1 and ADAM17. Next we tested the hypothesis that the sequential changes of gastric carcinogenesis, i.e. chronic atrophic gastritis, intestinal metaplasia and invasive carcinoma, are associated with a reallocation of the LGR5(+) cells. Interestingly, the spatial distribution of LGR5 changed: in non-neoplastic stomach mucosa, LGR5(+) cells were found predominantly in the mucous neck region; in intestinal metaplasia LGR5(+) cells were localized at the crypt base, and in GC LGR5(+) cells were present at the luminal surface, the tumour centre and the invasion front. The expression of LGR5 in the tumour centre and invasion front of GC correlated significantly with the local tumour growth (T-category) and the nodal spread (N-category). Furthermore, patients with LGR5(+) GCs had a shorter median survival (28.0±8.6 months) than patients with LGR5(-) GCs (54.5±6.3 months). Our results show that LGR5 is differentially expressed in gastrointestinal cancers and that the spatial histoanatomical distribution of LGR5(+) cells has to be considered when their tumour biological significance is sought.

The side population (SP) of tumor cell lines shares characteristics with tumor stem cells. The objective of this study was to phenotypically and genotypically characterize the SP of gastric cancer cell lines. SP cells were obtained from AGS and MKN45 gastric cancer cells using Hoechst 33342 staining and fluorescence-activated cell sorting. The cells were subsequently studied morphologically at cytology and immunocytochemistry, on the transcriptional level via gene array, and in cell culture using recultivation assays. Genes differentially expressed in SP cells were evaluated at immunohistochemistry in tissue samples from 486 patients with gastric cancer. The SP cells were smaller and rounder then non-SP cells. SP cells self-renewed in recultivation experiments and differentiated into SP and non-SP cells. Recultivated SP and non-SP cells exhibited distinct phenotypes in culture insofar as cell shape and colony formation. SP cells demonstrated increased levels of the stem cell markers CD133 and Musashi-1. Transcriptional analyses demonstrated that SP cells express genes that encode for stem cell properties including FZD7, HEY1, SMO, and ADAM17. It was observed that ADAM17 and FZD7 are differentially expressed in human gastric cancer, and FZD7-positive cancers are associated with significantly shorter patient survival. In conclusion, human gastric cancer cell lines enclose a phenotypically and genotypically distinct cell population with tumor stem cell features. Phenotypic characteristics of this distinct cell population are also present in gastric cancer tissue, and correlate with patient survival., (Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Objective: To present two exemplary cases of adenomatoid tumors., Design: Case report., Setting: Two laparoscopic centers in Germany., Patient(s): Two women of reproductive age with uterine adenomatoid tumors., Intervention(s): Laparoscopic tumor excision., Main Outcome Measure(s): Differential diagnostics of uterine masses., Result(s): Intraoperatively, tumor excision is difficult because of the missing capsule that allows simple enucleation of fibroids. Adenomatoid tumors need to be cut out of the myometrium because they are densely adherent, with no clear plane of cleavage. Definite exclusion of a malignant tumor is only possible by histologic workup., Conclusion(s): The above might lead to an intraoperative dilemma in the case of young women because a malignant tumor would implicate a more radical operative strategy. Nevertheless, owing to the benign nature of adenomatoid tumors and the lack of recurrence, simple resection with conservation of the surrounding tissue is the treatment of choice. The proper laparoscopic handling of such cases is illustrated and placed in context within the existing literature., (Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)