Refine
Has Fulltext
- yes (67)
Is part of the Bibliography
- yes (67)
Year of publication
Document Type
- Journal article (66)
- Conference Proceeding (1)
Language
- English (67) (remove)
Keywords
- adrenocortical carcinoma (10)
- obesity (5)
- metabolomics (4)
- 18F-FDG (3)
- CXCR4 (3)
- Cushing’s syndrome (3)
- FGFR (3)
- PET (3)
- adrenocortical cancer (3)
- biomarker (3)
Institute
- Medizinische Klinik und Poliklinik I (65)
- Comprehensive Cancer Center Mainfranken (16)
- Klinik und Poliklinik für Allgemein-, Viszeral-, Gefäß- und Kinderchirurgie (Chirurgische Klinik I) (14)
- Pathologisches Institut (14)
- Klinik und Poliklinik für Nuklearmedizin (13)
- Kinderklinik und Poliklinik (5)
- Medizinische Klinik und Poliklinik II (5)
- Theodor-Boveri-Institut für Biowissenschaften (5)
- Urologische Klinik und Poliklinik (4)
- Institut für diagnostische und interventionelle Radiologie (Institut für Röntgendiagnostik) (3)
Sonstige beteiligte Institutionen
Background:
Pre- and early clinical studies on patients with autoimmune diseases suggested that induction of regulatory T(T(reg)) cells may contribute to the immunosuppressive effects of glucocorticoids(GCs).
Objective:
We readdressed the influence of GC therapy on T(reg) cells in immunocompetent human subjects and naive mice.
Methods:
Mice were treated with increasing doses of intravenous dexamethasone followed by oral taper, and T(reg) cells in spleen and blood were analyzed by FACS. Sixteen patients with sudden hearing loss but without an inflammatory disease received high-dose intravenous prednisolone followed by stepwise dose reduction to low oral prednisolone. Peripheral blood T(reg) cells were analyzed prior and after a 14 day GC therapy based on different markers.
Results:
Repeated GC administration to mice for three days dose-dependently decreased the absolute numbers of T(reg) cells in blood (100 mg dexamethasone/kg body weight: 2.8 +/- 1.8 x 10(4) cells/ml vs. 33 +/- 11 x 10(4) in control mice) and spleen (dexamethasone: 2.8 +/- 1.9 x 10(5)/spleen vs. 95 +/- 22 x 10(5)/spleen in control mice), which slowly recovered after 14 days taper in spleen but not in blood. The relative frequency of FOXP3(+) T(reg) cells amongst the CD4(+) T cells also decreased in a dose dependent manner with the effect being more pronounced in blood than in spleen. The suppressive capacity of T(reg) cells was unaltered by GC treatment in vitro. In immunocompetent humans, GCs induced mild T cell lymphocytosis. However, it did not change the relative frequency of circulating T(reg) cells in a relevant manner, although there was some variation depending on the definition of the T(reg) cells (FOXP3(+): 4.0 +/- 1.5% vs 3.4 +/- 1.5%*; AITR(+): 0.660.4 vs 0.5 +/- 0.3%, CD127(low): 4.0 +/- 1.3 vs 5.0 +/- 3.0%* and CTLA4+: 13.8 +/- 11.5 vs 15.6 +/- 12.5%; * p < 0.05).
Conclusion:
Short-term GC therapy does not induce the hitherto supposed increase in circulating T(reg) cell frequency, neither in immunocompetent humans nor in mice. Thus, it is questionable that the clinical efficacy of GCs is achieved by modulating T(reg) cell numbers.
Purpose: The metabolically most active lesion in 2-deoxy-2-(\(^{18}\)F)fluoro-D-glucose (\(^{18}\)F-FDG) PET/CT can predict progression-free survival (PFS) in patients with medullary thyroid carcinoma (MTC) starting treatment with the tyrosine kinase inhibitor (TKI) vandetanib. However, this metric failed in overall survival (OS) prediction. In the present proof of concept study, we aimed to explore the prognostic value of intratumoral textural features (TF) as well as volumetric parameters (total lesion glycolysis, TLG) derived by pre-therapeutic \(^{18}\)F-FDG PET.
Methods: Eighteen patients with progressive MTC underwent baseline \(^{18}\)F-FDG PET/CT prior to and 3 months after vandetanib initiation. By manual segmentation of the tumor burden at baseline and follow-up PET, intratumoral TF and TLG were computed. The ability of TLG, imaging-based TF, and clinical parameters (including age, tumor marker doubling times, prior therapies and RET (rearranged during transfection) mutational status) for prediction of both PFS and OS were evaluated.
Results: The TF Complexity and the volumetric parameter TLG obtained at baseline prior to TKI initiation successfully differentiated between low- and high-risk patients. Complexity allocated 10/18 patients to the high-risk group with an OS of 3.3y (vs. low-risk group, OS=5.3y, 8/18, AUC=0.78, P=0.03). Baseline TLG designated 11/18 patients to the high-risk group (OS=3.5y vs. low-risk group, OS=5y, 7/18, AUC=0.83, P=0.005). The Hazard Ratio for cancer-related death was 6.1 for Complexity (TLG, 9.5). Among investigated clinical parameters, the age at initiation of TKI treatment reached significance for PFS prediction (P=0.02, OS, n.s.).
Conclusions: The TF Complexity and the volumetric parameter TLG are both independent parameters for OS prediction.
Introduction: The prognosis of medullary thyroid carcinoma (MTC) is poor using common chemotherapeutic approaches. However, during the last years encouraging results of recently introduced tyrosine kinase inhibitors (TKI) such as vandetanib have been published. In this study we aimed to correlate the results of \(^{18}\)F-fluorodeoxyglucose ([\(^{18}\)F]FDG) positron emission tomography (PET) imaging with treatment outcome.
Methods: Eighteen patients after thyroidectomy with recurrent/advanced MTC lesions receiving vandetanib (300 mg orally/day) could be analysed. A baseline \(^{18}\)F-FDG PET prior to and a follow-up \(^{18}\)F-FDG PET 3 months after TKI initiation were performed. During follow-up, tumor progression was assessed every 3 months including computed tomography according to RECIST. Progression-free survival (PFS) was correlated with the maximum standardized uptake value of \(^{18}\)F-FDG in lymph nodes (SUV(LN)max) or visceral metastases (SUV(MTS)max) as well as with clinical parameters using ROC analysis.
Results: Within median 3.6 years of follow-up, 9 patients showed disease progression at median 8.5 months after TKI initiation. An elevated glucose consumption assessed by baseline \(^{18}\)F-FDG PET (SUV(LN)max > 7.25) could predict a shorter PFS (2 y) with an accuracy of 76.5% (SUV(LN)max <7.25, 4.3 y; p=0.03). Accordingly, preserved tumor metabolism in the follow-up PET (SUV(MTS)max >2.7) also demonstrated an unfavorable prognosis (accuracy, 85.7%). On the other hand, none of the clinical parameters reached significance in response prediction.
Conclusions: In patients with advanced and progressive MTC, tumors with higher metabolic activity at baseline are more aggressive and more prone to progression as reflected by a shorter PFS; they should be monitored more closely. Preserved glucose consumption 3 months after treatment initiation was also related to poorer prognosis.
Introduction: Therapeutic options in advanced medullary thyroid carcinoma (MTC) have markedly improved since the introduction of tyrosine kinase inhibitors (TKI). We
aimed to assess the role of metabolic imaging using 2-deoxy-2-(\(^{18}\)F)fluoro-D-glucose (\(^{18}\)F-FDG) positron emission tomography/computed tomography (PET/CT) shortly before and 3 months after initiation of TKI treatment.
Methods: Eighteen patients with advanced and progressive MTC scheduled for vandetanib treatment underwent baseline \(^{18}\)F-FDG PET/CT prior to and 3 months after TKI treatment initiation. During follow-up, CT scans were performed every 3 months and analyzed according to Response Evaluation Criteria In Solid Tumors (RECIST). The predictive value for estimating progression-free (PFS) and overall survival (OS) was examined by investigating \(^{18}\)F-FDG mean/maximum standardized uptake values (SUVmean/max) of the metabolically most active lesion as well as by analyzing clinical parameters (tumor marker doubling times {calcitonin, carcinoembryonic antigen (CEA)}, prior therapies, RET (rearranged during transfection) mutational status, and disease type).
Results: Within a median follow-up of 5.2 years, 9 patients experienced disease progression after a median time interval of 2.1y whereas the remainder had ongoing disease control (n=5 partial response and n=4 stable disease). Eight of the 9 patients with progressive disease died from MTC after a median of 3.5y after TKI initiation.
Pre-therapeutic SUVmean >4.0 predicted a significantly shorter PFS (PFS: 1.9y vs. 5.2y; p=0.04). Furthermore, sustained high 18F-FDG uptake at 3 months with a SUVmean>2.8 tended to portend an unfavorable prognosis with a PFS of 1.9y (vs. 3.5y; p=0.3). Prolonged CEA doubling times were significantly correlated with longer PFS (r=0.7) and OS (r=0.76, p<0.01, respectively). None of the other clinical parameters had prognostic significance.
Conclusions: Pre-therapeutic \(^{18}\)F-FDG PET/CT holds prognostic information in patients with advanced MTC scheduled for treatment with the TKI vandetanib. Low tumor metabolism of SUVmean < 4.0 prior to treatment predicts longer progression-free survival.
Background:
Metastatic Adrenocortical Carcinoma (ACC) is a rare malignancy with a poor 5-year-survival rate (<15%). A surgical approach is recommended in selected patients if complete resection of distant metastasis can be achieved. To date there are only limited data on the outcome after surgical resection of hepatic metastases of ACC.
Methods:
A retrospective analysis of the German Adrenocortical Carcinoma Registry was conducted. Patients with liver metastases of ACC but without extrahepatic metastases or incomplete tumour resection were included.
Results:
Seventy-seven patients fulfilled these criteria. Forty-three patients underwent resection of liver metastases of ACC. Complete tumour resection (R0) could be achieved in 30 (69.8%). Median overall survival after liver resection was 76.1 months in comparison to 10.1 months in the 34 remaining patients with unresected liver metastases (p < 0.001). However, disease free survival after liver resection was only 9.1 months. Neither resection status (R0/R1) nor extent of liver resection were significant predictive factors for overall survival. Patients with a time interval to the first metastasis/recurrence (TTFR) of greater than 12 months or solitary liver metastases showed significantly prolonged survival.
Conclusions:
Liver resection in the case of ACC liver metastases can achieve long term survival with a median overall survival of more than 5 years, but disease free survival is short despite metastasectomy. Time to recurrence and single versus multiple metastases are predictive factors for the outcome.
Somatic mutations in protein kinase A catalytic α subunit (PRKACA) were found to be causative for 30-40% of cortisol-producing adenomas (CPA) of the adrenal gland, rendering PKA signalling constitutively active. In its resting state, PKA is a stable and inactive heterotetramer, consisting of two catalytic and two regulatory subunits with the latter inhibiting PKA activity. The human genome encodes three different PKA catalytic subunits and four different regulatory subunits that are preferentially expressed in different organs. In normal adrenal glands all regulatory subunits are expressed, while CPA exhibit reduced protein levels of the regulatory subunit IIβ. In this study, we linked for the first time the loss of RIIβ protein levels to the PRKACA mutation status and found the down-regulation of RIIβ to arise post-transcriptionally. We further found the PKA subunit expression pattern of different tumours is also present in the zones of the normal adrenal cortex and demonstrate that the different PKA subunits have a differential expression pattern in each zone of the normal adrenal gland, indicating potential specific roles of these subunits in the regulation of different hormones secretion.
The genetic mechanisms underlying adrenocortical tumor development are still largely unknown. We used high-resolution single nucleotide polymorphism microarrays (Affymetrix SNP 6.0) to detect copy number alterations (CNAs) and copy-neutral losses of heterozygosity (cnLOH) in 15 cortisol-secreting adrenocortical adenomas with matched blood samples. We focused on microalterations aiming to discover new candidate genes involved in early tumorigenesis and/or autonomous cortisol secretion. We identified 962 CNAs with a median of 18 CNAs per sample. Half of them involved noncoding regions, 89% were less than 100 kb, and 28% were found in at least two samples. The most frequently gained regions were 5p15.33, 6q16.1, 7p22.3-22.2, 8q24.3, 9q34.2-34.3, 11p15.5, 11q11, 12q12, 16q24.3, 20p11.1-20q21.11, and Xq28 (>= 20% of cases), most of them being identified in the same three adenomas. These regions contained among others genes like NOTCH1, CYP11B2, HRAS, and IGF2. Recurrent losses were less common and smaller than gains, being mostly localized at 1p, 6q, and 11q. Pathway analysis revealed that Notch signaling was the most frequently altered. We identified 46 recurrent CNAs that each affected a single gene (31 gains and 15 losses), including genes involved in steroidogenesis (CYP11B1) or tumorigenesis (CTNNB1, EPHA7, SGK1, STIL, FHIT). Finally, 20 small cnLOH in four cases affecting 15 known genes were found. Our findings provide the first high-resolution genome-wide view of chromosomal changes in cortisol-secreting adenomas and identify novel candidate genes, such as HRAS, EPHA7, and SGK1. Furthermore, they implicate that the Notch1 signaling pathway might be involved in the molecular pathogenesis of adrenocortical tumors.
Context:
Adrenal tumors have a prevalence of around 2% in the general population. Adrenocortical carcinoma (ACC) is rare but accounts for 2–11% of incidentally discovered adrenal masses. Differentiating ACC from adrenocortical adenoma (ACA) represents a diagnostic challenge in patients with adrenal incidentalomas, with tumor size, imaging, and even histology all providing unsatisfactory predictive values.
Objective:
Here we developed a novel steroid metabolomic approach, mass spectrometry-based steroid profiling followed by machine learning analysis, and examined its diagnostic value for the detection of adrenal malignancy.
Design:
Quantification of 32 distinct adrenal derived steroids was carried out by gas chromatography/mass spectrometry in 24-h urine samples from 102 ACA patients (age range 19–84 yr) and 45 ACC patients (20–80 yr). Underlying diagnosis was ascertained by histology and metastasis in ACC and by clinical follow-up [median duration 52 (range 26–201) months] without evidence of metastasis in ACA. Steroid excretion data were subjected to generalized matrix learning vector quantization (GMLVQ) to identify the most discriminative steroids.
Results:
Steroid profiling revealed a pattern of predominantly immature, early-stage steroidogenesis in ACC. GMLVQ analysis identified a subset of nine steroids that performed best in differentiating ACA from ACC. Receiver-operating characteristics analysis of GMLVQ results demonstrated sensitivity = specificity = 90% (area under the curve = 0.97) employing all 32 steroids and sensitivity = specificity = 88% (area under the curve = 0.96) when using only the nine most differentiating markers.
Conclusions:
Urine steroid metabolomics is a novel, highly sensitive, and specific biomarker tool for discriminating benign from malignant adrenal tumors, with obvious promise for the diagnostic work-up of patients with adrenal incidentalomas.
Background:
Recent decades have seen a rise in the incidence of well-differentiated (mainly papillary) thyroid carcinoma around the world. In Germany, the age-adjusted incidence of well-differentiated thyroid carcinoma in 2010 was 3.5 per 100 000 men and 8.7 per 100 000 women per year.
Method:
This review is based on randomized, controlled trials and multicenter trials on the treatment of well-differentiated thyroid carcinoma that were retrieved by a selective literature search, as well as on three updated guidelines issued in the past two years.
Results:
The recommended extent of surgical resection depends on whether the tumor is classified as low-risk or high-risk, so that papillary microcar cinomas, which carry a highly favorable prognosis, will not be overtreated. More than 90% of localized, well-differentiated thyroid carcinomas can be cured with a combination of surgery and radioactive iodine therapy. Radio active iodine therapy is also effective in the treatment of well-differentiated thyroid carcinomas with distant metastases, yielding a 10-year survival rate of 90%, as long as there is good iodine uptake and the tumor goes into remission after treatment; otherwise, the 10-year survival rate is only 10%. In the past two years, better treatment options have become available for radioactive-iodine-resistant thyroid carcinoma. Phase 3 studies of two different tyrosine kinase inhibitors have shown that either one can markedly prolong progression-free survival, but not overall survival. Their more common clinically significant side effects are hand-foot syndrome, hypertension, diarrhea, proteinuria, and weight loss.
Conclusion:
Slow tumor growth, good resectability, and susceptibility to radioactive iodine therapy lend a favorable prognosis to most cases of well-differentiated thyroid carcinoma. The treatment should be risk-adjusted and interdisciplinary, in accordance with the current treatment guidelines. Even metastatic thyroid carcinoma has a favorable prognosis as long as there is good iodine uptake. The newly available medical treatment options for radioactive-iodine-resistant disease need to be further studied.
Lack of Ubiquitin Specific Protease 8 (USP8) Mutations in Canine Corticotroph Pituitary Adenomas
(2016)
Purpose
Cushing’s disease (CD), also known as pituitary-dependent hyperadrenocorticism, is caused by adrenocorticotropic hormone (ACTH)-secreting pituitary tumours. Affected humans and dogs have similar clinical manifestations, however, the incidence of the canine disease is thousand-fold higher. This makes the dog an obvious model for studying the pathogenesis of pituitary-dependent hyperadrenocorticism. Despite certain similarities identified at the molecular level, the question still remains whether the two species have a shared oncogenetic background. Recently, hotspot recurrent mutations in the gene encoding for ubiquitin specific protease 8 (USP8) have been identified as the main driver behind the formation of ACTH-secreting pituitary adenomas in humans. In this study, we aimed to verify whether USP8 mutations also play a role in the development of such tumours in dogs.
Methods
Presence of USP8 mutations was analysed by Sanger and PCR-cloning sequencing in 38 canine ACTH-secreting adenomas. Furthermore, the role of USP8 and EGFR protein expression was assessed by immunohistochemistry in a subset of 25 adenomas.
Results
None of the analysed canine ACTH-secreting adenomas presented mutations in the USP8 gene. In a subset of these adenomas, however, we observed an increased nuclear expression of USP8, a phenotype characteristic for the USP8 mutated human tumours, that correlated with smaller tumour size but elevated ACTH production in those tumours.
Conclusions
Canine ACTH-secreting pituitary adenomas lack mutations in the USP8 gene suggesting a different genetic background of pituitary tumourigenesis in dogs. However, elevated nuclear USP8 protein expression in a subset of tumours was associated with a similar phenotype as in their human counterparts, indicating a possible end-point convergence of the different genetic backgrounds in the two species. In order to establish the dog as a useful animal model for the study of CD, further comprehensive studies are needed.