TY - JOUR
A1 - Wallaschek, Nina
A1 - Reuter, Saskia
A1 - Silkenat, Sabrina
A1 - Wolf, Katharina
A1 - Niklas, Carolin
A1 - Özge, Kayisoglu
A1 - Aguilar, Carmen
A1 - Wiegering, Armin
A1 - Germer, Christoph-Thomas
A1 - Kircher, Stefan
A1 - Rosenwald, Andreas
A1 - Shannon-Lowe, Claire
A1 - Bartfeld, Sina
T1 - Ephrin receptor A2, the epithelial receptor for Epstein-Barr virus entry, is not available for efficient infection in human gastric organoids
JF - PLoS Pathogens
N2 - Epstein-Barr virus (EBV) is best known for infection of B cells, in which it usually establishes an asymptomatic lifelong infection, but is also associated with the development of multiple B cell lymphomas. EBV also infects epithelial cells and is associated with all cases of undifferentiated nasopharyngeal carcinoma (NPC). EBV is etiologically linked with at least 8% of gastric cancer (EBVaGC) that comprises a genetically and epigenetically distinct subset of GC. Although we have a very good understanding of B cell entry and lymphomagenesis, the sequence of events leading to EBVaGC remains poorly understood. Recently, ephrin receptor A2 (EPHA2) was proposed as the epithelial cell receptor on human cancer cell lines. Although we confirm some of these results, we demonstrate that EBV does not infect healthy adult stem cell-derived gastric organoids. In matched pairs of normal and cancer-derived organoids from the same patient, EBV only reproducibly infected the cancer organoids. While there was no clear pattern of differential expression between normal and cancer organoids for EPHA2 at the RNA and protein level, the subcellular location of the protein differed markedly. Confocal microscopy showed EPHA2 localization at the cell-cell junctions in primary cells, but not in cancer cell lines. Furthermore, histologic analysis of patient tissue revealed the absence of EBV in healthy epithelium and presence of EBV in epithelial cells from inflamed tissue. These data suggest that the EPHA2 receptor is not accessible to EBV on healthy gastric epithelial cells with intact cell-cell contacts, but either this or another, yet to be identified receptor may become accessible following cellular changes induced by inflammation or transformation, rendering changes in the cellular architecture an essential prerequisite to EBV infection.
KW - Organoids
KW - ephitelial cells
KW - gastrointestinal infections
KW - cancers and neoplasms
KW - Epstein-Barr virus
KW - flow cytometry
KW - epithelium
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259206
VL - 17
IS - 2
ER -
TY - JOUR
A1 - Sbiera, Iuliu
A1 - Kircher, Stefan
A1 - Altieri, Barbara
A1 - Lenz, Kerstin
A1 - Hantel, Constanze
A1 - Fassnacht, Martin
A1 - Sbiera, Silviu
A1 - Kroiss, Matthias
T1 - Role of FGF Receptors and Their Pathways in Adrenocortical Tumors and Possible Therapeutic Implications
JF - Frontiers in Endocrinology
N2 - Adrenocortical carcinoma (ACC) is a rare endocrine malignancy and treatment of advanced disease is challenging. Clinical trials with multi-tyrosine kinase inhibitors in the past have yielded disappointing results. Here, we investigated fibroblast growth factor (FGF) receptors and their pathways in adrenocortical tumors as potential treatment targets. We performed real-time RT-PCR of 93 FGF pathway related genes in a cohort of 39 fresh frozen benign and malignant adrenocortical, 9 non-adrenal tissues and 4 cell lines. The expression of FGF receptors was validated in 166 formalin-fixed paraffin embedded (FFPE) tissues using RNA in situ hybridization (RNAscope) and correlated with clinical data. In malignant compared to benign adrenal tumors, we found significant differences in the expression of 16/94 FGF receptor pathway related genes. Genes involved in tissue differentiation and metastatic spread through epithelial to mesechymal transition were most strongly altered. The therapeutically targetable FGF receptors 1 and 4 were upregulated 4.6- and 6-fold, respectively, in malignant compared to benign adrenocortical tumors, which was confirmed by RNAscope in FFPE samples. High expression of FGFR1 and 4 was significantly associated with worse patient prognosis in univariate analysis. After multivariate adjustment for the known prognostic factors Ki-67 and ENSAT tumor stage, FGFR1 remained significantly associated with recurrence-free survival (HR=6.10, 95%CI: 1.78 – 20.86, p=0.004) and FGFR4 with overall survival (HR=3.23, 95%CI: 1.52 – 6.88, p=0.002). Collectively, our study supports a role of FGF pathways in malignant adrenocortical tumors. Quantification of FGF receptors may enable a stratification of ACC for the use of FGFR inhibitors in future clinical trials.
KW - normal adrenal glands
KW - adrenocortical tumors
KW - FGF-pathway
KW - FGFR
KW - RNA Expression
KW - RNAScope
KW - unsupervised clustering
KW - patient survival
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-251953
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Lenschow, Christina
A1 - Fuss, Carmina Teresa
A1 - Kircher, Stefan
A1 - Buck, Andreas
A1 - Kickuth, Ralph
A1 - Reibetanz, Joachim
A1 - Wiegering, Armin
A1 - Stenzinger, Albrecht
A1 - Hübschmann, Daniel
A1 - Germer, Christoph Thomas
A1 - Fassnacht, Martin
A1 - Fröhling, Stefan
A1 - Schlegel, Nicolas
A1 - Kroiss, Matthias
T1 - Case Report: Abdominal Lymph Node Metastases of Parathyroid Carcinoma: Diagnostic Workup, Molecular Diagnosis, and Clinical Management
JF - Frontiers in Endocrinology
N2 - Parathyroid carcinoma (PC) is an orphan malignancy accounting for only ~1% of all cases with primary hyperparathyroidism. The localization of recurrent PC is of critical importance and can be exceedingly difficult to diagnose and sometimes futile when common sites of recurrence in the neck and chest cannot be confirmed. Here, we present the diagnostic workup, molecular analysis and multimodal therapy of a 46-year old woman with the extraordinary manifestation of abdominal lymph node metastases 12 years after primary diagnosis of PC. The patient was referred to our endocrine tumor center in 2016 with the aim to localize the tumor causative of symptomatic biochemical recurrence. In view of the extensive previous workup we decided to perform [18F]FDG-PET-CT. A pathological lymph node in the liver hilus showed slightly increased FDG-uptake and hence was suspected as site of recurrence. Selective venous sampling confirmed increased parathyroid hormone concentration in liver veins. Abdominal lymph node metastasis was resected and histopathological examination confirmed PC. Within four months, the patient experienced biochemical recurrence and based on high tumor mutational burden detected in the surgical specimen by whole exome sequencing the patient received immunotherapy with pembrolizumab that led to a biochemical response. Subsequent to disease progression repeated abdominal lymph node resection was performed in 10/2018, 01/2019 and in 01/2020. Up to now (12/2020) the patient is biochemically free of disease. In conclusion, a multimodal diagnostic approach and therapy in an interdisciplinary setting is needed for patients with rare endocrine tumors. Molecular analyses may inform additional treatment options including checkpoint inhibitors such as pembrolizumab.
KW - parathyroid carcinoma
KW - abdominal lymph node metastases
KW - molecular diagnostics
KW - repeated surgery
KW - [18F]FDG-PET-CT
KW - immune check inhibitor
KW - pembrolizumab
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-233362
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Sbiera, Iuliu
A1 - Kircher, Stefan
A1 - Altieri, Barbara
A1 - Fassnacht, Martin
A1 - Kroiss, Matthias
A1 - Sbiera, Silviu
T1 - Epithelial and Mesenchymal Markers in Adrenocortical Tissues: How Mesenchymal Are Adrenocortical Tissues?
JF - Cancers
N2 - A clinically relevant proportion of adrenocortical carcinoma (ACC) cases shows a tendency to metastatic spread. The objective was to determine whether the epithelial to mesenchymal transition (EMT), a mechanism associated with metastasizing in several epithelial cancers, might play a crucial role in ACC. 138 ACC, 29 adrenocortical adenomas (ACA), three normal adrenal glands (NAG), and control tissue samples were assessed for the expression of epithelial (E-cadherin and EpCAM) and mesenchymal (N-cadherin, SLUG and SNAIL) markers by immunohistochemistry. Using real-time RT-PCR we quantified the alternative isoform splicing of FGFR 2 and 3, another known indicator of EMT. We also assessed the impact of these markers on clinical outcome. Results show that both normal and neoplastic adrenocortical tissues lacked expression of epithelial markers but strongly expressed mesenchymal markers N-cadherin and SLUG. FGFR isoform splicing confirmed higher similarity of adrenocortical tissues to mesenchymal compared to epithelial tissues. In ACC, higher SLUG expression was associated with clinical markers indicating aggressiveness, while N-cadherin expression inversely associated with these markers. In conclusion, we could not find any indication of EMT as all adrenocortical tissues lacked expression of epithelial markers and exhibited closer similarity to mesenchymal tissues. However, while N-cadherin might play a positive role in tissue structure upkeep, SLUG seems to be associated with a more aggressive phenotype.
KW - adrenocortical tissues
KW - EMT
KW - epithelial markers
KW - mesenchymal markers
KW - recurrence-free survival
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236486
SN - 2072-6694
VL - 13
IS - 7
ER -
TY - JOUR
A1 - Adam, Pia
A1 - Kircher, Stefan
A1 - Sbiera, Iuliu
A1 - Koehler, Viktoria Florentine
A1 - Berg, Elke
A1 - Knösel, Thomas
A1 - Sandner, Benjamin
A1 - Fenske, Wiebke Kristin
A1 - Bläker, Hendrik
A1 - Smaxwil, Constantin
A1 - Zielke, Andreas
A1 - Sipos, Bence
A1 - Allelein, Stephanie
A1 - Schott, Matthias
A1 - Dierks, Christine
A1 - Spitzweg, Christine
A1 - Fassnacht, Martin
A1 - Kroiss, Matthias
T1 - FGF-Receptors and PD-L1 in Anaplastic and Poorly Differentiated Thyroid Cancer: Evaluation of the Preclinical Rationale
JF - Frontiers in Endocrinology
N2 - Background
Treatment options for poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinoma are unsatisfactory and prognosis is generally poor. Lenvatinib (LEN), a multi-tyrosine kinase inhibitor targeting fibroblast growth factor receptors (FGFR) 1-4 is approved for advanced radioiodine refractory thyroid carcinoma, but response to single agent is poor in ATC. Recent reports of combining LEN with PD-1 inhibitor pembrolizumab (PEM) are promising.
Materials and Methods
Primary ATC (n=93) and PDTC (n=47) tissue samples diagnosed 1997-2019 at five German tertiary care centers were assessed for PD-L1 expression by immunohistochemistry using Tumor Proportion Score (TPS). FGFR 1-4 mRNA was quantified in 31 ATC and 14 PDTC with RNAscope in-situ hybridization. Normal thyroid tissue (NT) and papillary thyroid carcinoma (PTC) served as controls. Disease specific survival (DSS) was the primary outcome variable.
Results
PD-L1 TPS≥50% was observed in 42% of ATC and 26% of PDTC specimens. Mean PD-L1 expression was significantly higher in ATC (TPS 30%) than in PDTC (5%; p<0.01) and NT (0%, p<0.001). 53% of PDTC samples had PD-L1 expression ≤5%. FGFR mRNA expression was generally low in all samples but combined FGFR1-4 expression was significantly higher in PDTC and ATC compared to NT (each p<0.001). No impact of PD-L1 and FGFR 1-4 expression was observed on DSS.
Conclusion
High tumoral expression of PD-L1 in a large proportion of ATCs and a subgroup of PDTCs provides a rationale for immune checkpoint inhibition. FGFR expression is low thyroid tumor cells. The clinically observed synergism of PEM with LEN may be caused by immune modulation.
KW - tyrosine kinase inhibitor (TKI)
KW - immune checkpoint inhibitor (ICI)
KW - immunohistochemistry
KW - immunotherapy
KW - PD-L1
KW - FGFR
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244653
SN - 1664-2392
VL - 12
ER -
TY - JOUR
A1 - Weich, Alexander
A1 - Werner, Rudolf A.
A1 - Buck, Andreas K.
A1 - Hartrampf, Philipp E.
A1 - Serfling, Sebastian E.
A1 - Scheurlen, Michael
A1 - Wester, Hans-Jürgen
A1 - Meining, Alexander
A1 - Kircher, Stefan
A1 - Higuchi, Takahiro
A1 - Pomper, Martin G.
A1 - Rowe, Steven P.
A1 - Lapa, Constantin
A1 - Kircher, Malte
T1 - CXCR4-Directed PET/CT in Patients with Newly Diagnosed Neuroendocrine Carcinomas
JF - Diagnostics
N2 - We aimed to elucidate the diagnostic potential of the C-X-C motif chemokine receptor 4 (CXCR4)-directed positron emission tomography (PET) tracer \(^{68}\)Ga-Pentixafor in patients with poorly differentiated neuroendocrine carcinomas (NEC), relative to the established reference standard \(^{18}\)F-FDG PET/computed tomography (CT). In our database, we retrospectively identified 11 treatment-naïve patients with histologically proven NEC, who underwent \(^{18}\)F-FDG and CXCR4-directed PET/CT for staging and therapy planning. The images were analyzed on a per-patient and per-lesion basis and compared to immunohistochemical staining (IHC) of CXCR4 from PET-guided biopsies. \(^{68}\)Ga-Pentixafor visualized tumor lesions in 10/11 subjects, while \(^{18}\)F-FDG revealed sites of disease in all 11 patients. Although weak to moderate CXCR4 expression could be corroborated by IHC in 10/11 cases, \(^{18}\)F-FDG PET/CT detected significantly more tumor lesions (102 vs. 42; total lesions, n = 107; p < 0.001). Semi-quantitative analysis revealed markedly higher 18F-FDG uptake as compared to \(^{68}\)Ga-Pentixafor (maximum and mean standardized uptake values (SUV) and tumor-to-background ratios (TBR) of cancerous lesions, SUVmax: 12.8 ± 9.8 vs. 5.2 ± 3.7; SUVmean: 7.4 ± 5.4 vs. 3.1 ± 3.2, p < 0.001; and, TBR 7.2 ± 7.9 vs. 3.4 ± 3.0, p < 0.001). Non-invasive imaging of CXCR4 expression in NEC is inferior to the reference standard \(^{18}\)F-FDG PET/CT.
KW - CXCR4
KW - NET
KW - NEC
KW - 68Ga-Pentixafor
KW - 18F-FDG
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234231
SN - 2075-4418
VL - 11
IS - 4
ER -