[Show abstract][Hide abstract] ABSTRACT: Background: Malignant germ cell tumours are the most common malignant tumours in young men. They are histologically divided into seminomas and non-seminomas. Non-seminomas are further subdivided into embryonic carcinomas, yolk sac tumours, chorionic carcinomas, and teratomas. For the therapeutic management it is essential to differentiate between these histological subtypes. Methods: Investigated cases included normal testis (n=50), intratubular germ cell neoplasia (n=25), seminomas (n=67), embryonic carcinomas (n=56), yolk sac tumours (n=29), chorionic carcinomas (n=2), teratomas (n=7) and four metastases of YST's for their CK19 expression. In addition Leydig cell- (n=10) and Sertoli cell- tumours (n=4) were included in this study. Results: All investigated seminomas, embryonic carcinomas as well as normal testis and intratubular germ cell neoplasias did not express CK19. In contrast, all investigated yolk sac tumours strongly expressed CK19 protein. These findings became also evident in mixed germ cell tumours consisting of embryonic carcinomas and yolk sac tumours, although CK19-expression could also be observed in analysed chorionic carcinomas and epithelial components of teratomas. Conclusion: CK19 proved to be a sensitive marker to identify yolk sac tumours of the testis and to distinguish them from other germ cell tumours, especially seminomas and embryonic carcinomas. Virtual slides: The virtual slide(s) for this article can be found here:http://www.diagnosticpathology.diagnomx.eu/vs/4075546891400979.
[Show abstract][Hide abstract] ABSTRACT: Background:
Testicular germ cell tumors (TGCT) are the most common cancer entities in young men with increasing incidence observed in the last decades. For therapeutic management it is important, that TGCT are divided into several histological subtypes. MED15 is part of the multiprotein Mediator complex which presents an integrative hub for transcriptional regulation and is known to be deregulated in several malignancies, such as prostate cancer and bladder cancer role, whereas the role of the Mediator complex in TGCT has not been investigated so far. Aim of the study was to investigate the implication of MED15 in TGCT development and its stratification into histological subtypes.
Immunohistochemical staining (IHC) against Mediator complex subunit MED15 was conducted on a TGCT cohort containing tumor-free testis (n = 35), intratubular germ cell neoplasia unclassified (IGCNU, n = 14), seminomas (SEM, n = 107) and non-seminomatous germ cell tumors (NSGCT, n = 42), further subdivided into embryonic carcinomas (EC, n = 30), yolk sac tumors (YST, n = 5), chorionic carcinomas (CC, n = 5) and teratomas (TER, n = 2). Quantification of MED15 protein expression was performed through IHC followed by semi-quantitative image analysis using the Definiens software.
In tumor-free seminiferous tubules, MED15 protein expression was absent or only low expressed in spermatogonia. Interestingly, the precursor lesions IGCNU exhibited heterogeneous but partly very strong MED15 expression. SEM weakly express the Mediator complex subunit MED15, whereas NSGCT and especially EC show significantly enhanced expression compared to tumor-free testis.
In conclusion, MED15 is differentially expressed in tumor-free testis and TGCT. While MED15 is absent or low in tumor-free testis and SEM, NSGCT highly express MED15, hinting at the diagnostic potential of this marker to distinguish between SEM and NSGCT. Further, the precursor lesion IGCNU showed increased nuclear MED15 expression in the preinvasive precursor cells, which may provide diagnostic value to distinguish between benign and pre-malignant testicular specimen, and may indicate a role for MED15 in carcinogenesis in TGCT.
[Show abstract][Hide abstract] ABSTRACT: This is the second part of a two-part review on soft tissue tumours which may be encountered in the mediastinum. This review is based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart and provides an updated overview of mesenchymal tumours that have been reported in the mediastinum.
Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 09/2015; DOI:10.1007/s00428-015-1832-6 · 2.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements. The thymus is an important organ in the mediastinum, and many of the masses encountered in the mediastinum are related to this organ. Most neoplasms diagnosed in the mediastinum are epithelial tumours (thymomas and thymic carcinomas), lymphomas or germ cell tumours. In contrast, soft tissue tumours of the mediastinum are rare. In 1963, Pachter and Lattes systematically reviewed soft tissue pathology of the mediastinum, covering the hitherto described [2, 226, 227] In this review, based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart, we provide an updated overview of mesenchymal tumours that may be encountered in the mediastinum.
Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 09/2015; DOI:10.1007/s00428-015-1830-8 · 2.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This overview of the 4 edition of the WHO Classification of thymic tumors has two aims. First, to comprehensively list the established and new tumour entities and variants that are described in the new WHO Classification of thymic epithelial tumors, germ cell tumors, lymphomas, dendritic cell and myeloid neoplasms, and soft tissue tumors of the thymus and mediastinum; second, to highlight major differences in the new WHO Classification that result from the progress that has been made since the 3 edition in 2004 at immunohistochemical, genetic and conceptual levels. Refined diagnostic criteria for type A, AB, B1-B3 thymomas and thymic squamous cell carcinoma are given and will hopefully improve the reproducibility of the classification and its clinical relevance. The clinical perspective of the classification has been strengthened by involving experts from radiology, thoracic surgery and oncology; by incorporating state-of-the-art PET/CT images; and by depicting prototypic cytological specimens. This makes the thymus section of the new WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart a valuable tool for pathologists, cytologists and clinicians alike. The impact of the new WHO Classification on therapeutic decisions is exemplified in this overview for thymic epithelial tumors and mediastinal lymphomas, and future perspectives and challenges are discussed.
Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 08/2015; DOI:10.1097/JTO.0000000000000654 · 5.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Tumours of ovarian-epithelial type of the testis, including serous borderline tumours, represent very rare entities. They are identical to the surface epithelial tumours of the ovary and have been reported in patients from 14 to 68 years of age. We describe two cases of a 46- and a 39-year old man with incidental findings of intratesticular masses of the left respectively right testis. Under the assumption of a malignant testicular tumour the patients were subjected to inguinal orchiectomy. Histologically, the tumours were identical to their ovarian counterparts: They showed a cystic configuration with a fibrous wall and irregular papillary structures lined by partially multistratified columnar cells and areas of hobnail cells. Furthermore, there was mild cytological atypia with a proliferative activity of below 5% as proved by Ki67 staining; mitoses could not be detected. Immunohistochemically, the tumour cells displayed expression of pan-cytokeratin AE3, progesterone receptor, Wilms' tumour protein (WT1), and PAX8 (Paired box gene 8). Estrogen receptor was expressed in one case. Octamer-binding transcription factor-4 (OCT4), calretinin, thrombomodulin, and D2-40 were not expressed. Mutation testing of BRAF revealed a BRAF V600E mutation in one case, while testing for KRAS mutations proved to be negative in both. The BRAF mutated tumour showed strong cytosolic and membranous positivity for B-Raf also on immunohistochemical analysis. Comparative genomic hybridization of one case could not reveal any chromosomal aberrations.
[Show abstract][Hide abstract] ABSTRACT: Plakophilin (PKP) 1 is frequently downregulated in prostate cancer and therefore may play a tumor-suppressive role. In the present study, we stably knocked down PKP1 in the non-neoplastic, prostatic BPH-1 cell line. In the PKP1-deficient cells, the expression of keratin 14 was lost, and the apoptosis rate was significantly reduced indicating that the cells acquired new biological capabilities. Moreover, we analyzed the gene expression profile of the PKP1-deficient BPH-1 cells. Among the genes that were significantly altered upon PKP1 knockdown, we noticed several extracellular matrix (ECM)-related genes and identified sparc/osteonectin, cwcv, and kazal-like domains proteoglycan 1 (SPOCK1/testican-1) as a gene of interest. SPOCK1 is a component of the ECM and belongs to a matricellular protein family named secreted protein, acidic, cysteine-rich (SPARC). The role of SPOCK1 in prostate cancer has not been clearly elucidated. We analyzed SPOCK1 mRNA expression levels in different cancer databases and characterized its expression in 136 prostatic adenocarcinomas by immunohistochemistry and western blot. SPOCK1 revealed a cytoplasmic localization in the glandular epithelium of the prostate and showed a significant upregulation of mRNA and protein in prostate tumor samples. Our findings support the hypothesis that PKP1 may have a tumor-suppressive function and suggest an important role of SPOCK1 in prostate tumor progression. Collectively, altered expression of PKP1 and SPOCK1 appears to be a frequent and critical event in prostate cancer.
[Show abstract][Hide abstract] ABSTRACT: Objective
The capacity of thymomas to generate mature CD4+ effector T cells from immature precursors inside the tumor and export them to the blood is associated with thymoma-associated myasthenia gravis (TAMG). Why TAMG(+) thymomas generate and export more mature CD4+ T cells than MG(−) thymomas is unknown.Methods
Unfixed thymoma tissue, thymocytes derived thereof, peripheral blood mononuclear cells (PBMCs), T-cell subsets and B cells were analysed using qRT-PCR and western blotting. Survival of PBMCs was measured by MTT assay. FAS-mediated apoptosis in PBMCs was quantified by flow cytometry. NF-κB in PBMCs was inhibited by the NF-κB-Inhibitor, EF24 prior to FAS-Ligand (FASLG) treatment for apoptosis induction.ResultsExpression levels of the apoptosis inhibitor cellular FLICE-like inhibitory protein (c-FLIP) in blood T cells and intratumorous thymocytes were higher in TAMG(+) than in MG(−) thymomas and non-neoplastic thymic remnants. Thymocytes and PBMCs of TAMG patients showed nuclear NF-κB accumulation and apoptosis resistance to FASLG stimulation that was sensitive to NF-κB blockade. Thymoma removal reduced cFLIP expression in PBMCs.InterpretationWe conclude that thymomas induce cFLIP overexpression in thymocytes and their progeny, blood T cells. We suggest that the stronger cFLIP overexpression in TAMG(+) compared to MG(−) thymomas allows for the more efficient generation of mature CD4+ T cells in TAMG(+) thymomas. cFLIP overexpression in thymocytes and exported CD4+ T cells of patients with TAMG might contribute to the pathogenesis of TAMG by impairing central and peripheral T-cell tolerance.
[Show abstract][Hide abstract] ABSTRACT: In-depth analyses of cancer cell proteomes are needed to elucidate oncogenic pathomechanisms, as well as to identify potential drug targets and diagnostic biomarkers. However, methods for quantitative proteomic characterization of patient-derived tumors and in particular their cellular subpopulations are largely lacking. Here we describe an experimental set-up that allows quantitative analysis of proteomes of cancer cell subpopulations derived from either liquid or solid tumors. This is achieved by combining cellular enrichment strategies with quantitative Super-SILAC-based mass spectrometry followed by bioinformatic data analysis. To enrich specific cellular subsets, liquid tumors are first immunophenotyped by flow cytometry followed by FACS-sorting; for solid tumors, laser-capture microdissection is used to purify specific cellular subpopulations. In a second step, proteins are extracted from the purified cells and subsequently combined with a tumor-specific, SILAC-labeled spike-in standard that enables protein quantification. The resulting protein mixture is subjected to either gel electrophoresis or Filter Aided Sample Preparation (FASP) followed by tryptic digestion. Finally, tryptic peptides are analyzed using a hybrid quadrupole-orbitrap mass spectrometer, and the data obtained are processed with bioinformatic software suites including MaxQuant. By means of the workflow presented here, up to 8,000 proteins can be identified and quantified in patient-derived samples, and the resulting protein expression profiles can be compared among patients to identify diagnostic proteomic signatures or potential drug targets.
Journal of Visualized Experiments 02/2015; DOI:10.3791/52435 · 1.33 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Hintergrund und Ziele Vor dem sich ändernden Profil der Pathologie nehmen die Anforderungen an das Fach zu. Besondere Aspekte ergeben sich im Umgang mit dem Gewebe von Patienten, die einer neoadjuvanten Therapie zugeführt wurden. In diesem Beitrag wird vornehmlich auf Entwicklungen aus der translationalen Forschung eingegangen, welche die klinische Betrachtung und die histopathologische Gewebediagnostik bei Patienten mit Rektumkarzinomen beeinflussen. Methoden Anhand einer manuellen Literaturrecherche deutsch- und englischsprachiger Artikel der Jahre 2002 bis 2014 wurden wichtige neue Aspekte der molekularen Karzinogenese des Rektumkarzinoms ermittelt und deren Relevanz für die Diagnostik, Therapie und pathologischen Klassifikationen zusammengefasst. Ergebnisse Nach neoadjuvanter Therapie des Rektumkarzinoms müssen zahlreiche Besonderheiten mit klinischen Konsequenzen bei der makroskopischen Begutachtung, dem Präparatezuschnitt und der Tumorklassifikation beachtet werden. Trotz neuer Erkenntnisse über die molekulare Karzinogenese des Rektumkarzinoms existieren bislang keine außerhalb von Studien etablierten Biomarker, die das Ansprechen auf eine neoadjuvante Therapie vorhersagen. Schlussfolgerungen Durch Anwendung neoadjuvanter Therapieverfahren bei Patienten mit Rektumkarzinomen wird eine Vielzahl von Effekten erzielt, deren Auswirkungen weder lokal noch systemisch bisher vollständig verstanden sind. Letztlich werden Strategien und Behandlungskonzepte, die auf einem besseren Verständnis der Tumor- und Systembiologie basieren, zu Fortschritten in der Prognosebeurteilung und durch hierauf abgestimmte zielgerichtete Behandlungen auch zu einer Verbesserung der Therapieresultate verhelfen.
Der Onkologe 02/2015; 21(2):136-142. DOI:10.1007/s00761-014-2764-5 · 0.14 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The rarity of thymomas and lack of multi-institutional studies have hampered therapeutic progress for decades. To overcome this, the members of the International Thymic Malignancy Interest Group created a worldwide retrospective database. This database was analyzed regarding the demographic and geographic distribution of thymomas and the impact of different variables on survival and recurrence.
This study analyzed 4221 thymomas diagnosed between 1983 and 2012 with World Health Organization histotype information from the International Thymic Malignancy Interest Group database. Associations to survival and recurrence were studied by univariate and multivariate analyses.
Type B2 thymoma is the most common (28%) and type A the least common (12%) histotypes. They are significantly more frequent in Europe and the United States than Asia. Type A and AB occur at significantly higher age than other thymomas (64 and 57 years, respectively). There are no differences in gender distribution. Stage is lower in type A (90% in stages I-II) and AB than B1 to B3 thymomas (38% of type B3 in stage III). In univariate analysis, recurrence is significantly less frequent among stage I/II tumors, in type A and AB (recurrence rates, 1-2%) than B1 to B3 thymomas (2-7%). Multivariate analysis reveals an impact of age, stage, and resection status on survival and recurrence, whereas for histology there is only a significant impact on recurrence.
New findings are (1) geographic differences such as a lower incidence of type A and B2 thymoma in Asia; and (2) impact of stage and histology, the latter partially limited to early stage disease, on recurrence.
Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 02/2015; 10(2):367-372. DOI:10.1097/JTO.0000000000000393 · 5.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Hintergrund
Die lymphovaskuläre Invasion (LVI) gilt als wichtiger Prognosefaktor für die Rezidivbildung bei Patienten mit lokal begrenztem Urothelkarzinom der Harnblase (UCB) nach radikaler Zystektomie (RZE). Wir untersuchten die Bedeutung des immunhistochemischen (IHC-)Markers D2-40 für die Detektion einer LVI im Vergleich zur konventionellen Hämatoxylin-Eosin- (HE-)Färbung.
Material und Methoden
Es erfolgten HE- und IHC-Färbungen mittels D2-40-Antikörper repräsentativer Schnitte von 80 Patienten nach RZE. Alle Tumorschnitte wurden reevaluiert und verblindet auf das Vorhandensein einer LVI untersucht.
In der in HE-Färbung zeigten 53 Patienten (66,3 %) und in der IHC 44 Patienten (55 %) eine LVI. 13 Patienten (16,3 %) wiesen eine LVI nur in der HE-Färbung (HE-Färbung falsch-positiv; IHC als Referenz betrachtet) auf. Mittels D2-40 konnte bei 4 zusätzlichen Patienten (5 %) eine LVI diagnostiziert werden (falsch-negativ). 52 Patienten (65 %) wurden als pN0 klassifiziert, davon zeigten 21 (40,4 %) eine LVI in der HE- und 16 (30,8 %) eine LVI in der IHC-Färbung. Bei 9 Patienten im Stadium pN0 (17,3 %) wurde eine LVI durch IHC nicht bestätigt (falsch-positiv). Die IHC detektierte bei 4 zusätzlichen Patienten (7,7 %) eine LVI (falsch-negativ). Von diesen erlitten 3 Patienten ein Rezidiv des UCB. Bei Patienten mit Krankheitsrezidiv (n = 35) und pN0 zum Zeitpunkt der RZE zeigte die HE-Färbung bezüglich einer LVI falsch-positive Resultate bei 2 (5,7 %) und falsch-negative Ergebnisse bei 3 Patienten (8,6 %).
Die IHC mit D2-40 verändert die Detektionsraten der LVI im Vergleich zur konventionellen HE-Färbung. Ein routinemäßiger Einsatz der D2-40-IHC kann die Risikostratifizierung von Patienten ohne Lymphknotenmetastasen verbessern und für das Design innovativer klinischer Studien dienen.
Der Urologe 11/2014; 54(1). DOI:10.1007/s00120-014-3646-6 · 0.44 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Plakophilins 1 and 3 (PKP1/3) are members of the arm repeat family of catenin proteins and serve as structural components
of desmosomes, which are important for cell-cell-adhesion. In addition, PKP1/3 occur as soluble proteins outside desmosomes,
yet their role in the cytoplasm is not known. We found that cytoplasmic PKP1/3 coprecipitated with the RNA-binding proteins
FXR1, G3BP, PABPC1, and UPF1, and these PKP1/3 complexes also comprised desmoplakin and PKP2 mRNAs. Moreover, we showed that
the interaction of PKP1/3 with G3BP, PABPC1, and UPF1 but not with FXR1 was RNase sensitive. To address the cytoplasmic function
of PKP1/3, we performed gain-and-loss-of-function studies. Both PKP1 and PKP3 knockdown cell lines showed reduced protein
and mRNA levels for desmoplakin and PKP2. Whereas global rates of translation were unaffected, desmoplakin and PKP2 mRNA were
destabilized. Furthermore, binding of PKP1/3 to FXR1 was RNA independent, and both PKP3 and FXR1 stabilized PKP2 mRNA. Our
results demonstrate that cytoplasmic PKP1/3 are components of mRNA ribonucleoprotein particles and act as posttranscriptional
regulators of gene expression.
[Show abstract][Hide abstract] ABSTRACT: Stage classification is an important underpinning of management of patients with cancer, and rests on a combination of three components: T for tumor extent, N for nodal involvement, and M for more distant metastases. This article details an initiative to develop proposals for the first official stage classification system for thymic malignancies for the 8th edition of the stage classification manuals. Specifically, the results of analysis of a large database and the considerations leading to the proposed N and M components are described. Nodal involvement is divided into an anterior (N1) and a deep (N2) category. Metastases can involve pleural or pericardial nodules (M1a) or intraparenchymal pulmonary nodules or metastases to distant sites (M1b).
Journal of Thoracic Oncology 09/2014; 9(9):S81-7. · 5.28 Impact Factor