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Zusammenfassung. Die Sarkoidose ist eine seltene Ursache der Hyperkalzämie. Als häufigste Ursachen kommen ein primärer Hyperparathyreoidismus sowie ein malignes Tumorleiden in Frage. Weitere Ursachen können eine Vitamin-D-Intoxikation, sonstige granulomatöse Erkrankungen (Tuberkulose, Pilzinfektionen etc.) oder ein multiples Myelom sein. Aufgrund der breiten Differenzialdiagnose ist eine systematische Abklärung entscheidend, um die korrekte Diagnose zu stellen. Zur Therapie einer Hyperkalzämie erfolgt eine Volumensubstitution und anschliessende Gabe von Bisphosphonaten. Bei einer Sarkoidose als Ursache der Hyperkalzämie ist zudem eine systemische Steroidtherapie mit Prednisolon indiziert.

Highlights • SalvGlandDx includes 27 genes known to be involved in salivary gland neoplasms • Can be applied to FFPE histological and cytological (cell block) specimen • Solely RNA extraction is needed • Gene fusions, hotspot mutations and gene expression levels can be detected • Guides diagnosis in uncertain cases and can detect therapeutically relevant fusions, Diagnosis of salivary gland neoplasms is often challenging due to their high morphological diversity and overlaps. Several recurrent molecular alterations have been described recently, which can serve as powerful diagnostic tools and potential therapeutic targets (e.g. NTRK or RET fusions). However, current sequential molecular testing can be expensive and time consuming. In order to facilitate the diagnosis of salivary gland neoplasms, we designed an all-in-one RNA-based next generation sequencing panel suitable for the detection of mutations, fusions and gene expression levels (including NR4A3) of 27 genes involved in salivary gland neoplasms. Here we present the validation of the “SalvGlandDx” panel on FFPE histological specimen including fine needle aspiration (FNA) cell block material, against the standard methods currently used at our institution. In a second part we describe selected unique cases in which the SalvGlandDx panel allowed proper diagnosis and new insights into special molecular characteristics of selected salivary gland tumors. We characterize a unique salivary gland adenocarcinoma harboring a ZCCHC7-NTRK2 fusion, a highly uncommon spindle cell and pseudoangiomatoid adenoid-cystic carcinoma with MYBL1-NFIB fusion, and a purely oncocytic mucoepidermoid carcinoma, whereas diagnosis could be made by detection of a CRTC3-MAML2 rearrangement on the cell block specimen of the FNA. Further, a rare case of a SS18-ZBTB7A rearranged low-grade adenocarcinoma previously described as potential spectrum of microsecretory adenocarcinoma, is reported. In addition, features of six cases within the spectrum of polymorphous adenocarcinoma / cribriform adenocarcinoma of salivary gland including PRKD1 p.E710D mutations and novel fusions involving PRKAR2A-PRKD1, SNX9-PRKD1 and ATL2-PRKD3, are described.

Background Fos like 2 (Fosl-2) is a transcription factor belonging to the AP-1 transcription complex. We have recently described a Fosl-2 transgenic (tg) mouse model which develops a multi-organ inflammatory and autoimmune phenotype. In these mice, we have characterized a decrease in regulatory T cells (Tregs), which preceded the activation of T cells and the development of inflammation. Objectives To analyze how Fosl-2 reduces the Treg population and triggers autoimmunity in Fosl-2 tg mice. Methods We used previously generated Fosl-2 tg overexpressing and Fosl-2 T cell specific knock out (Fosl-2 ko) mice. For mixed bone marrow transfer experiments, lethally irradiated recipients received a one to one mix of Fosl-2 tg (CD45.2) and wt (CD45.1) bone marrow to create Fosl-2 tg-wt chimera. We addressed the contribution of Tregs to the inflammatory phenotype by co-transferring Fosl-2 tg CD4 T cells and wt Tregs to Rag2-/- recipients. Treg and T cell populations were analyzed by flow cytometry and inflammation was addressed by CD45 staining on paraffin-embedded sections. RNA-sequencing was used to compare wt, Fosl-2 tg and Fosl-2 ko CD4 T cells after 24 hours of stimulation with anti-CD3 (2μg/ml) and anti-CD28 (2μg/ml). Results We first addressed whether Fosl-2 affected Tregs in a cell intrinsic way using mixed bone marrow experiments. In these animals, the CD45.2 Fosl-2 tg CD4 T cells showed a much lower proportion of Tregs compared to the CD45.1 wt population, both in the spleen (0.73%±0.15 vs 31.6%±3.6, P=0.062) and thymus (1.3%±1.04 vs 3.23%±0.78, P=0.001). This demonstrates that Fosl-2 overexpression represses Treg development in a cell intrinsic way. In T cell transfer experiments, Rag2-/- mice receiving 106 Fosl-2 tg CD4 cells developed lung inflammation 5 weeks after transfer, confirming that T cells are inducers of inflammation in Fosl-2 tg mice. Moreover, co-transfer of either 3*105 or 106 wt Treg cells resulted in a dose dependent reduction of inflammation. These data indicated that the decrease in the Treg population in Fosl-2 tg mice is responsible for the induction of inflammation. We then analysed Fosl-2 transcriptional targets in T cells by RNA-seq. Using a fold change > 1.5 and False Discovery Rate (FDR) of 0.05, we identified 191 differentially expressed genes in both Fosl-2 tg and Fosl-2 ko cells compared to wt. Interestingly, one of the top target genes of Fosl-2 was FoxP3. This unbiased approach thus revealed that FoxP3 expression is repressed by Fosl-2, with a 6.5 fold reduction in Fosl-2 tg cells and a 2.5 fold increase in Fosl-2 ko cells. This effect was confirmed on the protein level with a reduction in FoxP3 induction in Fosl-2 tg cells treated with TGFβ. The repression of Treg development observed in Fosl-2 tg mice could thus be explained by a direct transcriptional control of FoxP3 expression. Additionally, we found that Fosl-2 repressed a set of genes important for Tregs and other T helper cells. This included Nr4a2, a transcription factor involved in Treg development, IRF8 and Eomes, two genes involved in the polarization of Th1 and Th17 cells, or Ccl1 a chemokine important for Treg homeostasis. Conclusion Fosl-2 is involved in the control of FoxP3 expression in T cells. Through this, overexpression of Fosl-2 represses Treg development and induces a Treg dependent autoimmune phenotype in mice. This mechanism could thus be involved in the pathogenesis of autoimmune diseases and might represent a therapeutic target to modulate the Treg population. Disclosure of Interests Florian Renoux: None declared, Mara Stellato: None declared, Alexander Vogetseder: None declared, Riyung Huang: None declared, Arun Subramaniam: None declared, Przemyslaw Blyszczuk: None declared, Jorg Distler: None declared, Gabriela Kania: None declared, Onur Boyman: None declared, Oliver Distler Grant/research support from: Prof. Distler received research funding from Actelion, Bayer, Boehringer Ingelheim and Mitsubishi Tanabe to investigate potential treatments of scleroderma and its complications, Consultant for: Prof. Distler has/had consultancy relationship within the last 3 years with Actelion, AnaMar, Bayer, Boehringer Ingelheim, ChemomAb, espeRare foundation, Genentech/Roche, GSK, Inventiva, Italfarmaco, iQvia, Lilly, medac, MedImmune, Mitsubishi Tanabe Pharma, Pharmacyclics, Novartis, Pfizer, Sanofi, Serodapharm and UCB in the area of potential treatments of scleroderma and its complications. In addition, he had/has consultancy relationship within the last 3 years with A. Menarini, Amgen, Abbvie, GSK, Mepha, MSD, Pfizer and UCB in the field of arthritides and related disorders

Background Fos-related antigen 2 (Fra2) is a transcription factor belonging to the Fos family proteins which is part of the AP-1 transcription complex. We recently described a Fra2 transgenic (tg) mouse model which develops a multi-organ inflammatory phenotype affecting skin, lungs, thymus, liver and salivary glands. We have observed abnormalities in the T cell compartment, particularly in regulatory T (Treg) cells, which led us to hypothesize that Fra2 tg mice develop a T cell driven autoimmune phenotype. Objectives To demonstrate the autoimmune phenotype of Fra2 tg mice and to characterize the mechanisms leading to Treg cell abnormality. Methods We used previously generated Fra2 tg overexpressing mice. T lymphocyte populations were analyzed by flow cytometry for expression of activation markers and secretion of cytokines. We transferred purified CD4+ T cells into Rag2-/- mice lacking T and B cells, and we generated Rag2-/-Fra2 tg mice. Bone marrow cells were transferred into lethally irradiated recipients to create Fra2-WT bone marrow chimeric mice. Results Fra2 tg mice backcrossed onto a Rag2-/- background did not develop inflammatory manifestations (n=6), demonstrating the dependence on T and/or B cells of the autoimmune phenotype. In line with this, the transfer of purified CD4+ cells from 16 week-old Fra2 tg mice into Rag2-/- recipients was sufficient to transfer the disease phenotype (n=3). Analysis of T cell populations from Fra2 tg mice showed the presence of activated CD4+ and CD8+ cells in the spleen and lungs. After in vitro stimulation, we found that CD4+ T cells from Fra2 tg mice produced the Th2 cytokines IL-4, IL-5 and IL-13. Thus, these data strongly suggest a T cell-driven autoimmune disease in these mice. We previously reported a striking decrease of Treg cells in Fra2 tg mice, which might explain the autoimmune phenotype observed. Supporting this idea, we found that 3 week-old mice were devoid of organ manifestations and of T cell activation, but presented the same defect in the Treg cell population (n=6, p Conclusions Our data suggest that Fra2 controls tTreg cell development, possibly by modulating IL-2 signaling in T cells, which leads to autoimmunity in this mouse model. This new pathway could be targeted in a translational approach to modulate the capacity of T cells to differentiate in Tregs during autoimmune disease. Disclosure of Interest F. Renoux Grant/research support from: Swisslife, M. Stellato: None declared, D. Impellizzieri: None declared, A. Vogetseder: None declared, R. Huang Employee of: Sanofi-Genzyme, A. Subramaniam Employee of: Sanofi-Genzyme, C. Dees: None declared, J. Distler Shareholder of: 4D Science, Grant/research support from: Anamar, Active Biotech, Array Biopharma, BMS, Bayer Pharma, Boehringer Ingelheim, Celgene, GSK, Novartis, Sanofi-Aventis, UCB, Consultant for: Actelion, Active Biotech, Anamar, Bayer Pharma, Boehringer Ingelheim, Celgene, Galapagos, GSK, Inventiva, JB Therapeutics, Medac, Pfizer, RuiYi and UCB, G. Kania: None declared, O. Boyman: None declared, O. Distler Grant/research support from: Actelion, Bayer, Boehringer Ingelheim, Pfizer, Sanofi, Consultant for: 4 D Science, Actelion, Active Biotec, Bayer, BiogenIdec, BMS, Boehringer Ingelheim, ChemomAb, EpiPharm, espeRare foundation, Genentech/Roche, GSK, Inventiva, Lilly, medac, Mepha, MedImmune, Mitsubishi Tanabe Pharma, Pharmacyclics, Pfizer, Sanofi, Serodapharm, Sinoxa, Speakers bureau: AbbVie, iQone Healthcare, Mepha

Cancer-testis antigens (CTAgs) play a major role in the immune response against cancer, but their biological functions in germ and cancer cells is still unclear. MAGE-C1 and MAGE-C2 are two CTAgs located at the Xq27 region of chromosome X and frequently expressed in multiple myeloma. Chromosomal rearrangements often occur in myeloma. We therefore investigated whether numerical and structural chromosomal aberrations correlate with their protein expression in primary multiple myelomas. To this aim, we designed new fluorescence in situ hybridization probes specific for the MAGE region in the Xq27 region and evaluated simultaneously aberrations of the X chromosome centromere. The comparison of MAGE copy number and chromosome X status revealed that MAGE copy number changes occurred in 6/43 (14%) cases, independent of concomitant X chromosome alterations. These numerical aberrations are less frequent than the expression of MAGE-C1 and MAGE-C2 (63% and 27% of patients, respectively) and do not always correlate with MAGE-C1 and MAGE-C2 expressions, suggesting alternative regulatory mechanisms in the expression of these genes. Copyright © 2014 John Wiley & Sons, Ltd.

To determine whether metastasis to brain is associated with altered expression patterns of integrins, we investigated the expression of αvβ3, αvβ5, αvβ6 and αvβ8 integrins in primary malignancies and metastases to brain of breast, lung and renal carcinomas and in malignant melanoma. Inhibitors of αv integrins are currently in clinical trials for glioblastoma. The role of integrins in the process of brain metastasis from other human tumors is unknown. Immunohistochemistry with novel integrin subtype specific rabbit monoclonal antibodies was performed on tissue microarrays of archival material of surgical biopsies taken from primary tumors and brain metastases. Integrin αvβ3 expression was increased in brain metastases compared to primary tumors of breast adenocarcinoma, non-small cell lung cancer, renal clear cell cancer and malignant cutaneous melanoma (all p

Worldwide, various autopsy studies have shown a decrease in the diagnostic error rate over the last years. The cause of this positive development is mainly due to the improvement of modern medicine. However, intensive care unit patients are thought to have a higher risk for diagnostic errors, which is documented in several studies in the adult population. In contrast, there is only limited information about diagnostic errors in pediatrics, particularly in pediatric and neonatal intensive care units. The aims of this study were to analyze the spectrum of childhood death, determine the prevalence and distribution of autopsy-confirmed diagnostic errors, and describe patient characteristics that might have influenced the discordance between antemortem and postmortem findings. We analyzed 143 autopsy reports from 2004 to 2013 and correlated these with clinical reports. The overall autopsy rate during this interval was 20.3%. The leading causes of death were congenital malformations (28%), diseases closely associated with perinatal disorders (25%), disorders of the cardiovascular system (18%), and infections (15%). Additional findings were obtained in 23% of the autopsies. Major diagnostic errors were found in 6%, the lowest reported value in a developed country as yet. Most cases (75%) showed complete concordance between clinical diagnoses and postmortem findings, in line with improvements in diagnostic and therapeutic processes over the last decades. In conclusion, autopsy of neonates, infants, and children represents an important tool for monitoring the quality of pediatric and neonatal medical care.

Zusammenfassung: Wir beschreiben einen testikulären primitiven neuroektodermalen Tumor (PNET) mit intratubulärer Keimzellneoplasie des angrenzenden Hodenparenchyms bei einem 25-jährigen Patienten. Testikuläre PNET sind selten. Ihre Entstehung wird auf eine maligne somatische Transformation in einem testikulären Keimzelltumor zurückgeführt. Morphologisch und molekularpathologisch ähneln diese Tumoren kindlichen zentralen PNET, die keine Rearrangierung des EWS-Gens auf Chromosom22 aufweisen. Auch im hier beschriebenen Fall konnte keine Translokation nachgewiesen werden

P-cadherin (CDH3) and CD24 are cell adhesion molecules that control morphogenic processes, cell motility, and invasive growth of tumor cells. The aim of our study was to investigate P-cadherin and CD24 expression in carcinomas and dysplastic lesions of the biliary tract and to evaluate the potential diagnostic usefulness of these cell adhesion molecules. Using immunohistochemistry on tissue microarrays, we analyzed P-cadherin, CD24, and p53 expression in 117 carcinomas of the biliary tract (19 intrahepatic cholangiocarcinomas, 59 extrahepatic cholangiocarcinomas, and 39 gallbladder carcinomas) and correlated our findings with clinicopathologic parameters. We found P-cadherin positivity in 37% of intrahepatic cholangiocarcinomas, 73% of extrahepatic cholangiocarcinomas, and 64% of gallbladder carcinomas, respectively. CD24 reactivity was observed in 21% of intrahepatic cholangiocarcinomas, 58% of extrahepatic cholangiocarcinomas, and 42% of gallbladder carcinomas. Nuclear p53 expression was found in 37% of intrahepatic cholangiocarcinomas, 46% of extrahepatic cholangiocarcinomas, and 45% of gallbladder carcinomas. We also studied P-cadherin, CD24, and p53 expression in normal (n = 30), inflamed (n = 22), and dysplastic (n = 21) biliary epithelium of extrahepatic bile ducts. Dysplastic biliary epithelium was positive for P-cadherin in 91%, for CD24 in 71%, and for p53 in 24% of lesions, respectively. In contrast, normal and inflamed epithelia were negative for all 3 proteins. We conclude that P-cadherin and CD24 are expressed in carcinomas of the biliary tract with high frequency and at an early stage of carcinogenesis. Therefore, they may be useful markers for early detection and as targets for therapy of cholangiocarcinoma.

Regulation of cytotoxic effector molecule expression in human CTLs after viral or bacterial activation is poorly understood. By using human autologous dendritic cells (DCs) to prime T lymphocytes, we found perforin only highly up-regulated in virus- (HSV-1, vaccinia virus) but not in intracellular bacteria- (Listeria innocua, Listeria monocytogenes, Mycobacterium tuberculosis, Chlamydophila pneumoniae) activated CTLs. In contrast, larger quantities of IFN-γ and TNF-α were produced in Listeria-stimulated cultures. Granzyme B and granulysin were similarly up-regulated by all tested viruses and intracellular bacteria. DCs infected with HSV-1 showed enhanced surface expression of the costimulatory molecule CD252 (CD134L) compared with Listeria-infected DC and induced enhanced secretion of IL-2. Adding blocking CD134 or neutralizing IL-2 Abs during T cell activation reduced the HSV-dependent up-regulation of perforin. These data indicate a distinct CTL effector function in response to intracellular pathogens triggered via differing endogenous IL-2 production upon costimulation through CD252.

Background Cheilitis granulomatosa and Melkersson–Rosenthal syndrome are both rare and benign diseases. Because of their granulomatous character, a relationship to Crohn's disease has been suggested. Furthermore, because of their unknown aetiology, treatment is difficult, and evaluation of response is hampered by the natural tendency to spontaneous resolution and recurrence. Objectives and methods To evaluate gastrointestinal involvement by clinical history, conventional endoscopy, and capsule endoscopy as well as to compare efficacy of treatment modalities on a series of 14 patients, one of the biggest collectives reported. Results Four patients (4 of 14) were previously, simultaneously, or subsequently diagnosed with Crohn's disease. In six patients (6 of 14) with minor gastrointestinal symptoms as flatulence, occasional constipation, diarrhoea, or admixture of mucus with the stool, we could not detect any signs of inflammatory bowel disease by capsule endoscopy. Nine patients received clofazimine, and eight patients responded to treatment (four complete responses, four partial responses). Two patients were successfully treated with infliximab. Systemic methylprednisone was not successful in two patients. Conclusion Close to 30% of patients showed an association of cheilitis granulomatosa and Crohn's disease. Forty-three per cent of patients reported minor gastrointestinal irregularities without any detectable changes of Crohn's disease. Clofazimine seems to be an effective treatment, although long-term application is necessary with frequent aggravation in the beginning. Infliximab, an effective drug in Crohn's disease, could be a promising treatment option for severe cases.

We studied 38 patients with malaria tropica over a period of 5 days during antiparasitic therapy. Serum or plasma levels of interleukin (IL) 1beta, IL-6, IL-10, tumour necrosis factor-alpha (TNF-alpha), the soluble vascular adhesion molecule (sVCAM) and the soluble intracellular adhesion molecule (sICAM) were determined by enzyme-linked immunosorbent assay. Protein C and antithrombin III activity were analysed by chromogenic tests and protein S activity by a clotting test. Antithrombin III, protein C and protein S activity was significantly lower in patients with severe malaria and displayed a highly significant increase in activity over the time of evaluation. Levels of sVCAM and sICAM were increased for the whole study period, but no significant differences were found between severe and mild malaria cases. Serum IL-1beta, IL-6 and IL-10 levels were significantly higher in patients with severe malaria, whereas no significant differences were found for TNF-alpha. IL-6 and IL-10 decreased significantly over 5 days during schizontocidal therapy. Our data show an impairment of the coagulation system which correlates with pro-inflammatory cytokines and therefore with the severity of the disease.

The eukaryotic translation initiation factor (eIF) 3a, the largest subunit of the eIF3 complex, is a key functional entity in ribosome establishment and translation initiation. In the past, aberrant eIF3a expression has been linked to the pathology of various cancer types but, so far, its expression has not been investigated in transitional cell carcinomas. Here, we investigated the impact of eIF3 expression on urinary bladder cancer (UBC) cell characteristics and UBC patient survival. eIF3a expression was reduced through inducible knockdown in the UBC-derived cell lines RT112, T24, 5637 and HT1197. As a consequence of eIF3a down-regulation, UBC cell proliferation, clonogenic potential and motility were found to be decreased and, concordantly, UBC tumour cell growth rates were found to be impaired in xenotransplanted mice. Polysomal profiling revealed that reduced eIF3a levels increased the abundance of 80S ribosomes, rather than impairing translation initiation. Microarray-based gene expression and ontology analyses revealed broad effects of eIF3a knockdown on the transcriptome. Analysis of eIF3a expression in primary formalin-fixed paraffin embedded UBC samples of 198 patients revealed that eIF3a up-regulation corresponds to tumour grade and that high eIF3a expression corresponds to longer overall survival rates of patients with low grade tumours. From our results we conclude that eIF3a expression may have a profound effect on the UBC phenotype and, in addition, may serve as a prognostic marker for low grade UBCs.

OBJECTIVES: Smoking increases the risk of developing rheumatoid arthritis (RA) and worsens the course of the disease. In the current study we analysed whether smoking can affect gene expression directly in the joints. METHODS: Synovial fibroblasts were incubated with 5 cigarette smoke extract and changes in gene expression were detected using whole genome microarrays and verified with real time PCR. Synovial tissues were obtained from smoking and non smoking patients with RA undergoing joint replacement surgery and from mice exposed to cigarette smoke or ambient air in a whole body exposure chamber for 3 weeks. RESULTS: Microarray and real time PCR analysis showed a significant upregulation of the heat shock proteins DnaJA4 DnaJB4 DnaJC6 HspB8 and Hsp70 after stimulation of synovial fibroblasts with 5 cigarette smoke extract. Similarly in synovial tissues of smokers with RA the expression of DnaJB4 DnaJC6 HspB8 and Hsp70 was significantly higher compared with non smokers with RA. Upregulation of DnaJB4 and DnaJC6 in joints by smoking was also confirmed in mice exposed to cigarette smoke. CONCLUSIONS: Our data clearly show that smoking can change gene expression in the joints which can lead to the activation of signalling pathways that promote development of autoimmunity and chronic joint inflammation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights licensing/permissions.

Human endogenous retroviruses (HERVs) are widely believed to represent possible pathogenic agents in autoimmune disorders and carcinogenesis. We generated 2 monoclonal antibodies (mAbs) against a recombinant HERV-K outer-membrane envelope protein. These mAbs were capable of immunoprecipitating protein bands of 55, 51 and 45 kDa, respectively, from [ 35 S]methionine-labeled lysates of T47D (human breast carcinoma), Raji, Bjab (both human β-lymphoblastoid) and H9 (human T-cell lymphoma) cells. Furthermore, the 55 kDa band could be precipitated from cell-free supernatant of biosynthetically labeled T47D cells, indicating that this molecule may be secreted. Indirect immunofluorescence and subsequent FACS analysis demonstrated the presence of these molecules on T47D, HeLa, Raji, Bjab and H9 cells as well as on lymphocytes isolated from tonsils and stimulated with poke weed mitogen (PWM). Due to the broad distribution and lack of detection of HERV-K-env mRNA in these cells, we believe that these antigens are of cellular origin detected by crossreactivity of mAbs against HERV-K-env protein with cellular molecules.

Objective:The most difficult thyroid tumors to be diagnosed by cytology and histology are conventional follicular carcinomas (cFTCs) and oncocytic follicular carcinomas (oFTCs). Several microRNAs (miRNAs) have been previously found to be consistently deregulated in papillary thyroid carcinomas; however, very limited information is available for cFTC and oFTC. The aim of this study was to explore miRNA deregulation and find candidate miRNA markers for follicular carcinomas that can be used diagnostically.Design:Thirty-eight follicular thyroid carcinomas (21 cFTCs, 17 oFTCs) and 10 normal thyroid tissue samples were studied for expression of 381 miRNAs using human microarray assays. Expression of deregulated miRNAs was confirmed by individual RT-PCR assays in all samples. In addition, 11 follicular adenomas, two hyperplastic nodules (HNs), and 19 fine-needle aspiration samples were studied for expression of novel miRNA markers detected in this study.Results:The unsupervised hierarchical clustering analysis demonstrated individual clusters for cFTC and oFTC, indicating the difference in miRNA expression between these tumor types. Both cFTCs and oFTCs showed an up-regulation of miR-182/-183/-221/-222/-125a-3p and a down-regulation of miR-542-5p/-574-3p/-455/-199a. Novel miRNA (miR-885-5p) was found to be strongly up-regulated (>40-fold) in oFTCs but not in cFTCs, follicular adenomas, and HNs. The classification and regression tree algorithm applied to fine-needle aspiration samples demonstrated that three dysregulated miRNAs (miR-885-5p/-221/-574-3p) allowed distinguishing follicular thyroid carcinomas from benign HNs with high accuracy.Conclusions:In this study we demonstrate that different histopathological types of follicular thyroid carcinomas have distinct miRNA expression profiles. MiR-885-5p is highly up-regulated in oncocytic follicular carcinomas and may serve as a diagnostic marker for these tumors. A small set of deregulated miRNAs allows for an accurate discrimination between follicular carcinomas and hyperplastic nodules and can be used diagnostically in fine-needle aspiration biopsies.

The efficacy of mammalian target of rapamycin (mTOR) inhibitors is currently tested in patients affected by autosomal dominant polycystic kidney disease. Treatment with mTOR inhibitors has been associated with numerous side effects. However, the renal-specific effect of mTOR inhibitor treatment cessation in polycystic kidney disease is currently unknown. Therefore, we compared pulse and continuous everolimus treatment in Han:SPRD rats. Four-week-old male heterozygous polycystic and wild-type rats were administered everolimus or vehicle by gavage feeding for 5 wk, followed by 7 wk without treatment, or continuously for 12 wk. Cessation of everolimus did not result in the appearance of renal cysts up to 7 wk postwithdrawal despite the reemergence of S6 kinase activity coupled with an overall increase in cell proliferation. Pulse everolimus treatment resulted in striking noncystic renal parenchymal enlargement and glomerular hypertrophy that was not associated with compromised kidney function. Both treatment regimens ameliorated kidney function, preserved the glomerular-tubular connection, and reduced proteinuria. Pulse treatment at an early age delays cyst development but leads to striking glomerular and parenchymal hypertrophy. Our data might have an impact when long-term treatment using mTOR inhibitors in patients with autosomal dominant polycystic kidney disease is being considered.

Carcinomas of the Vaterian system are rare and presumably arise from preexisting adenomas (adenoma-carcinoma-sequence). Usually, biopsies are obtained to confirm and specify endoscopic findings, but differentiating reactive atypia from dysplasia or dysplasia from invasive carcinoma can sometimes be difficult or even impossible on morphological criteria alone. In case of invasive carcinoma, furthermore, the precise classification of carcinoma subtypes needs to be established since the distinct subtypes differ significantly in terms of clinical outcome. The cell adhesion proteins CD24, P-cadherin and S100A4 were shown to be expressed in several carcinomas and in dysplastic epithelium but only rarely in normal mucosa. We therefore investigated their expression in 177 carcinoma, 114 adenoma and 152 normal mucosa specimens of the ampulla of Vater. Although the expression of the cell adhesion proteins did not differ between the carcinoma subtypes, marked differences between normal mucosa, adenoma and carcinoma samples were observed. All marker proteins were expressed in less than 7% of normal mucosa samples (S100A4 in only 1% of cases) and showed an increasing expression from adenoma to invasive carcinoma. Our findings suggest that P-cadherin and S100A4 are helpful in discriminating normal mucosa or reactive atypia from neoplastic lesions. CD24 and S100A4, furthermore, can assist in the differential diagnosis of dysplasia vs invasive carcinoma.

During a study on the mTor pathway in the rat kidney we observed a striking increase of the phosphorylation of the S6 kinase in mitosis. In cryostat sections of perfusion-fixed tissue mitotic cells appeared as bright spots in immunofluorescence using an antibody specific for the phosphorylation site Thr421/Ser424. They were easily spotted in overviews with the objective 4x and 10x. Immunofluorescence was weak during the interphase. During the prophase it increased in both the nucleus and the cytoplasm and it remained bright during the subsequent phases of mitosis. All mitotic cells which were found in tubules and in the interstitium of the kidney using a chromatin stain displayed the bright immunofluorescence for phospho-S6 kinase. The same phenomenon was observed in rat liver and in mouse kidney as well as in a human cell line. Provided a rapid fixation, mitotic cells could be identified with the immunoperoxidase technique in paraffin sections of immersion-fixed tissue. This is the first report of phosphorylation of S6 kinase during mitosis in vivo. Thus, immunohistochemistry with anti-phospho-S6 kinase (Thr421/Ser424) appears to provide a convenient way to detect mitotic cells at low magnification.

SUMMARY: Aim: Autosomal dominant polycystic kidney disease (ADPKD) is characterized by an imbalance between tubular epithelial cell proliferation and apoptosis. We have previously shown that the mammalian target of rapamycin (mTOR) signalling pathway is aberrantly activated in the cystic kidneys of Han:SPRD rats with ADPKD. Because the Akt kinase is an upstream regulator of mTOR, we hypothesized that the activity of Akt could be enhanced in the kidneys of Han:SPRD rats. Methods: Reverse transcription-polymerase chain reaction, western blot, enzyme-linked immunosorbent assay and immunohistochemistry were used to analyse Akt expression in rat polycystic kidneys. Results: Wild-type (+/+) and heterozygous (Cy/+) Han:SPRD rats showed constitutive expression of Akt-1, -2 and -3 mRNA by reverse transcription-polymerase chain reaction analysis with no significant difference between Cy/+ and +/+ kidneys. Western blotting and enzyme-linked immunosorbent assay showed a significant increase in phosphorylated Akt in Cy/+ compared with +/+ kidneys. The pattern of immunoreactivity for phosphorylated Akt in kidney sections was the same in +/+ and in Cy/+ rats, with very low levels in interphase cells, but extremely bright signals in mitotic cells, beginning with the onset of the prophase. The in vivo incorporation of bromo-deoxyuridine revealed approximately a ninefold higher rate of proliferation in Cy/+ cyst epithelia compared with normal tubule epithelia in +/+ rats, while the expression of the cell cycle marker Ki67 revealed approximately a sixfold higher rate of proliferation. In summary, enhanced phosphorylation of Akt can be demonstrated in Cy/+ kidneys which correlates with a markedly elevated proliferation rate of epithelial cells in cysts. Mitotic but not resting cells display strong phosphorylation of Akt. Conclusion: Because Akt is a proximal target of mTOR, its inhibition with specific antagonists could be useful to prevent or halt cystogenesis in ADPKD.

We searched for evidence for a contribution of stem cells in growth of the proximal S3 segments of healthy rats. According to the stem cell model, stem cells are undifferentiated and slow cycling; the bulk of cycling cells are transit amplifying, rapidly cycling cells. We show the following. 1) By continuous application of a thymidine analog (ThA) for 7 days, S3 proximal epithelial cells in healthy kidneys display a high-cycling rate. 2) Slow-cycling cells, identified by lack of ThA uptake during 14 days of continuous ThA application up to death and by expression of the cell cycle protein Ki67 at death, have the same degree of differentiation as quiescent cells. 3) To detect rapidly cycling cells, rats were killed at various time points after injection of a ThA. Double immunofluorescence for ThA and a cell cycle marker was performed, with colocalization indicating successive divisions. During one week after division, daughter cells display a very low proliferation rate, indicating the absence of rapidly cycling cells. 4) Labeling with cyclin D1 showed that this low proliferation rate is due to cycle arrest. 5) More than 50% of the S3 cells entered the cell cycle 36 h after a potent proliferative stimulus (lead acetate injection). We conclude that generation of new cells in the proximal tubule relies on division of differentiated, normally slow-cycling cells. These may rapidly enter the cycle under an adequate stimulus.

We searched for morphological evidence to support the hypothesis that stem cells are responsible for renal tubular cell proliferation. The rationale of the study was that if proliferation relies on progenitors, mitotically active cells should be less differentiated than their neighbors. As the retention of the thymidine analog BrdU has been the only approach employed to identify stem cells in the kidney up to now we additionally characterized BrdU-retaining cells. Rat kidneys were fixed by perfusion. Cycling cells identified by mitotic figures or the expression of the proliferating cell nuclear antigen (PCNA) were examined by light microscopy and electron microscopy as well as immunofluorescence for four differentiation markers. Newborn rats were injected with BrdU in order to detect label-retaining cells. After a period of 8, 14 and 35 weeks the kidneys were examined for BrdU by immunofluorescence and the four differentiation markers mentioned above. All cycling cells showed the same degree of differentiation compared to non-cycling cells. Most of the detected label-retaining cells were differentiated. We conclude that cycling cells in tubules of the healthy kidney are differentiated and that the retention of label is not a criterion to identify stem cells in renal tubules.

Human endogenous retrovirus (HERV) K is present in about 50 copies in the human genome and transcription of HERV-K has previously been detected in several tumor cell lines as well as in peripheral blood lymphocytes from healthy donors. By means of immunoblotting we investigated the presence of antibodies recognizing recombinant HERV-K-envelope outer membrane constructs in different serum collectives. A total of 12.6% of sera obtained from normal blood donors was found positive. In serum collectives from breast carcinoma patients, HIV-1-positive individuals, and persons with cytomegalovirus infections no significant difference from the normal blood donor serum collective could be observed. Only a group of persons with a repeatedly raised serum neopterin concentration (10 nmol/liter) of unknown cause (HIV and hepatitis B and C virus infections were excluded) showed a significant higher percentage of HERV-K-outer membrane envelope-positive sera (21%). Furthermore we could observe a parallel HIV-1/HERV-K seroconversion, which probably is not due to an HIV-1/HERV-K-outer membrane envelope cross-reactivity. Possible implications of these findings are discussed.

A group of 92 medical students were immunized with a commercial recombinant hepatitis B vaccine (Engerix B). Antibody responses were determined and compared with those to plasma-derived Pasteur vaccine, obatined in 1986. Antibody concentrations were significantly higher in the group given recombinant vaccine, therefore this vaccine has superior immunogenicity and probably confers extended duration of protection.

To assess the role of complement and complement receptors in HIV-1 infection of monocytes and macrophages, we studied the infectivity of HIV-1, isolated from the peripheral blood of a patient with subacute AIDS-related encephalopathy, on the human monoblastoid cell line U937. HIV-1 and HIV-1-infected cells were capable of activating the complement system via the classical and the alternative pathways, respectively. Low concentrations of HIV-1 were able to infect U937 cells more easily in the presence than in the absence of complement. At higher virus concentrations, infectivity was no longer facilitated by the presence of complement. Infection of U937 cells was reduced in the presence of any of the monoclonal antibodies (MAbs), OKT4a (anti-CD4), OKM1 (anti-CR3), or M522 (anti-CR3). A combination of all three of these MAbs reduced the infection by an even greater amount. These data indicate that complement receptors may be a port of entry for complement-coated HIV-1.

The membrane molecule termed “7F7-antigen” has been found to be involved in several examples of cell-cell interactions. This 85 kDa glycoprotein with a protein core of about 55 kDa contains N-linked and O-linked carbohydrates. It has an isoelectric point of 8.0–8.5 and is expressed on 20% of peripheral blood mononuclear cells, 35% of peripheral blood B-cells, follicular dendritic cells and vascular endothelium. It is also expressed on activated T-cells and its expression on B-cells, fibroblasts and monocytes increases after treatment with PWM, interferon-gamma and after three days culture, respectively. The MAb 7F7 used to define this antigen inhibits the initiation of T-cell proliferation induced by anti-CD3, PHA, ConA and (weakly) allogenic stimulator cells, but does not affect the growth of IL-2 dependent T-cells and does not interfere with the killing of PHA-blasts by allogenic IL-2 dependent T-cells. 7F7 also inhibits the binding of C3-coated sheep erythrocytes to B-cells, the PMA-induced aggregation of U937 and the binding of activated T-cells to fibroblasts. The 7F7-antigen is expressed on some non-Hodgkin lymphomas of B-cell differentiation, particularly those with follicular structure, but not on Burkitt's lymphoma, ALL or carcinomas of various tissues. It is, however, found on fibrous tissue surrounding infiltrating carcinoma cells. The expression of a melanoma antigen, P3.58, which was shown to be identical to 7F7-antigen correlates with stage and spread of invasive melanoma. It was concluded that the 7F7-antigen, which is probably related to a previously described adherence molecule (ICAM-1), is of biological importance for the initiation of T-cell responses. With the possible exception of melanoma its expression on neoplastic cells in vivo is unlikely to be of importance for the spread of malignant disease.

A monoclonal antibody, 7F7, raised against the Raji B lymphoblastoid cell line reacted with about 35% of peripheral blood B cells, germinal center B cells, follicular dendritic cells and some vascular endothelial cells. Although not found on resting T cells this antigen was strongly expressed on CD4+ and CD8+ T cells activated with phytohemagglutinin, pokeweed mitogen and anti-T3, and its expression on B cells was enhanced after stimulation with pokeweed mitogen. It is strongly expressed 24 h after stimulation with phytohemagglutinin and its expression is reduced but not eliminated by cyclosporin A treatment. The molecule defined by antibody 7F7 is found on some, but not all, B cell lines, on an HTLV-I-transformed T cell line and on the promyelocytic cell line U937. Immunoprecipitation from externally and metabolically labeled Raji cells revealed a single-chain molecule of 85 kDa.

The 7F7-antigen is a widespread 85-kDa membrane adherence molecule involved in heterotypic adhesion between PHA-blasts and fibroblasts. Immunofluorescence analysis of COS cells transfected with clone pICAM-I indicated that 7F7-antigen is identical with ICAM-I, the ligand for the contact molecule LFA-I. We have investigated the expression of ICAM-I on several human carcinomas. Tumor cells in most carcinomas, with the exception of squamous-cell carcinomas, expressed very little ICAM-I or none at all. In contrast, marked expression of this molecule was observed on fibrous tissue in the vicinity of carcinoma cells, its intensity correlating with lymphatic infiltration in these tumors. We also examined the expression of ICAM-I on carcinoma cell lines and its induction by treatment with interferon-gamma (IFN-gamma). The inducibility of ICAM-I expression on cultured fibroblasts by several lymphokines suggests that the expression of ICAM-I in the vicinity of carcinoma cells is effected by lymphokines produced by activated lymphocytes/macrophages within the tumor.

A monoclonal antibody, 7F7, directed at a recently described membrane activation antigen of 85 kDa was found to inhibit the T cell proliferation induced by an anti-CD3 antibody, phytohemagglutinin A and concanavalin A. The T cell response to allogenic stimulator cells was also weakly inhibited. The inhibition of these T cell responses was only obtained if the antibody was added within the first 8 h (first 24 h in the case of the concanavalin A response) of culture. In addition the antibody inhibited the formation of cellular aggregates seen in stimulated cultures when added within the first 8 h. The membrane glycoprotein recognized by 7F7 is shown to have a slightly different molecular mass on cells of different lineage, a protein core of 55 kDa and to contain 30–50% of N-linked as well as a small amount of 0-linked carbohydrates and sialic acid residues. This study suggests that the highly glycosylated membrane activation antigen defined by antibody 7F7 could contribute to the contact between those cells which are involved in the initiation of T cell responses.