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 - 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 - 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 - 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 - 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 -