Whole genome sequencing resolves 10 years diagnostic odyssey in familiar myxoma.

Carney complex (CNC) is an ultrarare disorder causing cutaneous and cardiac myxomas, primary pigmented nodular adrenocortical disease, hypophyseal adenoma, and gonadal tumours. Genetic alterations are often missed under routine genetic testing. Pathogenic variants in PRKAR1A are identified in most cases, while large exonic or chromosomal deletions have only been reported in a few cases. Our aim was to identify the causal genetic alteration in our kindred with a clinical diagnosis of CNC and prove its pathogenic role by functional investigation. Targeted testing of PRKAR1A gene, whole exome and whole genome sequencing (WGS) were performed in the proband, one clinically affected and one unaffected relative. WGS identified a novel, large, 10,662 bp (10.6 kbp; LRG_514t1:c.-10403_-7 + 265del; hg19, chr17:g.66498293_66508954del) deletion in the promoter of PRKAR1A in heterozygous form in the affected family members. The exact breakpoints and the increased enzyme activity in deletion carriers compared to wild type carrier were proved. Segregation analysis and functional evaluation of PKA activity confirmed the pathogenic role of this alteration. A novel deletion upstream of the PRKAR1A gene was proved to be the cause of CNC. Our study underlines the need for WGS in molecular genetic testing of patients with monogenic disorders where conventional genetic analysis fails.

Context-Dependent Role of Glucocorticoid Receptor Alpha and Beta in Breast Cancer Cell Behaviour.

Background. The dual role of GCs has been observed in breast cancer; however, due to many concomitant factors, GR action in cancer biology is still ambiguous. In this study, we aimed to unravel the context-dependent action of GR in breast cancer. Methods. GR expression was characterized in multiple cohorts: (1) 24,256 breast cancer specimens on the RNA level, 220 samples on the protein level and correlated with clinicopathological data; (2) oestrogen receptor (ER)-positive and -negative cell lines were used to test for the presence of ER and ligand, and the effect of the GRß isoform following GRα and GRß overexpression on GR action, by in vitro functional assays. Results. We found that GR expression was higher in ER- breast cancer cells compared to ER+ ones, and GR-transactivated genes were implicated mainly in cell migration. Immunohistochemistry showed mostly cytoplasmic but heterogenous staining irrespective of ER status. GRα increased cell proliferation, viability, and the migration of ER- cells. GRß had a similar effect on breast cancer cell viability, proliferation, and migration. However, the GRß isoform had the opposite effect depending on the presence of ER: an increased dead cell ratio was found in ER+ breast cancer cells compared to ER- ones. Interestingly, GRα and GRß action did not depend on the presence of the ligand, suggesting the role of the "intrinsic", ligand-independent action of GR in breast cancer. Conclusions. Staining differences using different GR antibodies may be the reason behind controversial findings in the literature regarding the expression of GR protein and clinicopathological data. Therefore, caution in the interpretation of immunohistochemistry should be applied. By dissecting the effects of GRα and GRß, we found that the presence of the GR in the context of ER had a different effect on cancer cell behaviour, but independently of ligand availability. Additionally, GR-transactivated genes are mostly involved in cell migration, which raises GR's importance in disease progression.

A common genetic variation in GZMB may associate with cancer risk in patients with Lynch syndrome.

Lynch syndrome (LS), also known as hereditary nonpolyposis colorectal cancer syndrome (HNPCC) is a common genetic predisposition to cancer due to germline mutations in genes affecting DNA mismatch repair. Due to mismatch repair deficiency, developing tumors are characterized by microsatellite instability (MSI-H), high frequency of expressed neoantigens and good clinical response to immune checkpoint inhibitors. Granzyme B (GrB) is the most abundant serine protease in the granules of cytotoxic T-cells and natural killer cells, mediating anti-tumor immunity. However, recent results confirm a diverse range of physiological functions of GrB including that in extracellular matrix remodelling, inflammation and fibrosis. In the present study, our aim was to investigate whether a frequent genetic variation of GZMB, the gene encoding GrB, constituted by three missense single nucleotide polymorphisms (rs2236338, rs11539752 and rs8192917) has any association with cancer risk in individuals with LS. In silico analysis and genotype calls from whole exome sequencing data in the Hungarian population confirmed that these SNPs are closely linked. Genotyping results of rs8192917 on a cohort of 145 individuals with LS demonstrated an association of the CC genotype with lower cancer risk. In silico prediction proposed likely GrB cleavage sites in a high proportion of shared neontigens in MSI-H tumors. Our results propose the CC genotype of rs8192917 as a potential disease-modifying genetic factor in LS.

Aspirin Mediates Its Antitumoral Effect Through Inhibiting PTTG1 in Pituitary Adenoma.

CONTEXT: DNA demethylation and inhibitory effects of aspirin on pituitary cell proliferation have been demonstrated. OBJECTIVE: Our aim was to clarify the molecular mechanisms behind the aspirin-related effects in pituitary cells. METHODS: DNA methylome and whole transcriptome profile were investigated in RC-4B/C and GH3 pituitary cell lines upon aspirin treatment. Effects of aspirin and a demethylation agent, decitabine, were further tested in vitro. PTTG1 expression in 41 human PitNET samples and whole genome gene and protein expression data of 76 PitNET and 34 control samples (available in Gene Expression Omnibus) were evaluated. RESULTS: Aspirin induced global DNA demethylation and consequential transcriptome changes. Overexpression of Tet enzymes and their cofactor Uhrf2 were identified behind the increase of 5-hydroxymethylcytosine (5hmC). Besides cell cycle, proliferation, and migration effects that were validated by functional experiments, aspirin increased Tp53 activity through p53 acetylation and decreased E2f1 activity. Among the p53 controlled genes, Pttg1 and its interacting partners were downregulated upon aspirin treatment by inhibiting Pttg1 promoter activity. 5hmC positively correlated with Tet1-3 and Tp53 expression, and negatively correlated with Pttg1 expression, which was reinforced by the effect of decitabine. Additionally, high overlap (20.15%) was found between aspirin-regulated genes and dysregulated genes in PitNET tissue samples. CONCLUSION: A novel regulatory network has been revealed, in which aspirin regulated global demethylation, Tp53 activity, and Pttg1 expression along with decreased cell proliferation and migration. 5hmC, a novel tissue biomarker in PitNET, indicated aspirin antitumoral effect in vitro as well. Our findings suggest the potential beneficial effect of aspirin in PitNET.

Exploratory Circular RNA Profiling in Adrenocortical Tumors.

Differentiation of adrenocortical adenoma (ACA) and carcinoma (ACC) is often challenging even in the histological analysis. Circular RNAs (circRNAs) belonging to the group of non-coding RNAs have been implicated as relevant factors in tumorigenesis. Our aim was to explore circRNA expression profiles in adrenocortical tumors by next-generation sequencing followed by RT-qPCR validation. Archived FFPE (formalin-fixed, paraffin embedded) including 8 ACC, 8 ACA and 8 normal adrenal cortices (NAC) were used in the discovery cohort. For de novo and known circRNA expression profiling, a next-generation sequencing platform was used. CIRI2, CircExplorer2, AutoCirc bioinformatics tools were used for the discovery of circRNAs. The top five most differentially circRNAs were measured by RT-qPCR in an independent validation cohort (10 ACC, 8 ACA, 8 NAC). In silico predicted, interacting microRNAs potentially sponged by differentially expressed circRNAs were studied by individual RT-qPCR assays. We focused on overexpressed circRNAs here. Significantly differentially expressed circRNAs have been revealed between the cohorts by NGS. Only circPHC3 could be confirmed to be significantly overexpressed in ACC, ACA vs. NAC samples by RT-qPCR. We could not observe microRNA expression changes fully corresponding to our sponging hypothesis. To the best of our knowledge, our study is the first to investigate circRNAs in adrenocortical tumors. Further studies are warranted to explore their biological and diagnostic relevance.

Extracellular Vesicle-Mediated Metastasis Suppressors NME1 and NME2 Modify Lipid Metabolism in Fibroblasts.

Nowadays, extracellular vesicles (EVs) raise a great interest as they are implicated in intercellular communication between cancer and stromal cells. Our aim was to understand how vesicular NME1 and NME2 released by breast cancer cells influence the tumour microenvironment. As a model, we used human invasive breast carcinoma cells overexpressing NME1 or NME2, and first analysed in detail the presence of both isoforms in EV subtypes by capillary Western immunoassay (WES) and immunoelectron microscopy. Data obtained by both methods showed that NME1 was present in medium-sized EVs or microvesicles, whereas NME2 was abundant in both microvesicles and small-sized EVs or exosomes. Next, human skin-derived fibroblasts were treated with NME1 or NME2 containing EVs, and subsequently mRNA expression changes in fibroblasts were examined. RNAseq results showed that the expression of fatty acid and cholesterol metabolism-related genes was decreased significantly in response to NME1 or NME2 containing EV treatment. We found that FASN (fatty acid synthase) and ACSS2 (acyl-coenzyme A synthetase short-chain family member 2), related to fatty acid synthesis and oxidation, were underexpressed in NME1/2-EV-treated fibroblasts. Our data show an emerging link between NME-containing EVs and regulation of tumour metabolism.

Surprising genetic and pathological findings in a patient with giant bilateral periadrenal tumours: PEComas and mutations of PTCH1 in Gorlin-Goltz syndrome.

Gorlin-Goltz syndrome (GGS) or nevoid basal cell carcinoma syndrome is a rare tumour-overgrowth syndrome associated with multiple developmental anomalies and a wide variety of tumours. Here, we describe a case of a man aged 23 years with GGS with bilateral giant tumours adjacent to both adrenals that raised the suspicion of malignancy on imaging. Histological analysis of both surgically resected tumours revealed perivascular epitheloid cell tumours (PEComas) that were independent of the adrenals. Exome sequencing of the patient's blood sample revealed a novel germline heterozygous frameshift mutation in the PTCH1 gene. As a second hit, a somatic five nucleotide long deletion in the PTCH1 gene was demonstrated in the tumour DNA of both PEComas. To the best of our knowledge, this is the first report on PEComa in GGS, and this finding also raises the potential relevance of PTCH1 mutations and altered sonic hedgehog signalling in PEComa pathogenesis. The presence of the same somatic mutation in the bilateral tumours might indicate the possibility of a postzygotic somatic mutation that along with the germline mutation of the same gene could represent an intriguing genetic phenomenon (type 2 segmental mosaicism).

Wnt-Signaling Regulated by Glucocorticoid-Induced miRNAs.

Glucocorticoids (GCs) are pleiotropic hormones which regulate innumerable physiological processes. Their comprehensive effects are due to the diversity of signaling mechanism networks. MiRNAs, small, non-coding RNAs contribute to the fine tuning of signaling pathways and reciprocal regulation between GCs and miRNAs has been suggested. Our aim was to investigate the expressional change and potential function of GC mediated miRNAs. The miRNA expression profile was measured in three models: human adrenocortical adenoma vs. normal tissue, steroid-producing H295R cells and in hormonally inactive HeLa cells before and after dexamethasone treatment. The gene expression profile in 82 control and 57 GC-affected samples was evaluated in GC producing and six different GC target tissue types. Tissue-specific target prediction (TSTP) was applied to identify the most relevant miRNA-mRNA interactions. Glucocorticoid treatment resulted in cell type-dependent miRNA expression changes. However, 19.5% of the influenced signaling pathways were common in all three experiments, of which the Wnt-signaling pathway seemed to be the most affected. Transcriptome data and TSTP showed similar results, as the Wnt pathway was significantly altered in both the GC-producing adrenal gland and all investigated GC target tissue types. In different cell types, different miRNAs led to the regulation of similar pathways. Wnt signaling may be one of the most important signaling pathways affected by hypercortisolism. It is, at least in part, regulated by miRNAs that mediate the glucocorticoid effect. Our findings on GC producing and GC target tissues suggest that the alteration of Wnt signaling (together with other pathways) may be responsible for the leading symptoms observed in Cushing's syndrome.

Analytical Performance of NGS-Based Molecular Genetic Tests Used in the Diagnostic Workflow of Pheochromocytoma/Paraganglioma.

Next Generation Sequencing (NGS)-based methods are high-throughput and cost-effective molecular genetic diagnostic tools. Targeted gene panel and whole exome sequencing (WES) are applied in clinical practice for assessing mutations of pheochromocytoma/paraganglioma (PPGL) associated genes, but the best strategy is debated. Germline mutations of at the least 18 PPGL genes are present in approximately 20-40% of patients, thus molecular genetic testing is recommended in all cases. We aimed to evaluate the analytical and clinical performances of NGS methods for mutation detection of PPGL-associated genes. WES (three different library preparation and bioinformatics workflows) and an in-house, hybridization based gene panel (endocrine-onco-gene-panel- ENDOGENE) was evaluated on 37 (20 WES and 17 ENDOGENE) samples with known variants. After optimization of the bioinformatic workflow, 61 additional samples were tested prospectively. All clinically relevant variants were validated with Sanger sequencing. Target capture of PPGL genes differed markedly between WES platforms and genes tested. All known variants were correctly identified by all methods, but methods of library preparations, sequencing platforms and bioinformatical settings significantly affected the diagnostic accuracy. The ENDOGENE panel identified several pathogenic mutations and unusual genotype-phenotype associations suggesting that the whole panel should be used for identification of genetic susceptibility of PPGL.

Molecular genetic diagnostics of hypogonadotropic hypogonadism: from panel design towards result interpretation in clinical practice.

Congenital hypogonadotropic hypogonadism (CHH) is a clinically and genetically heterogeneous congenital disease. Symptoms cover a wide spectrum from mild forms to complex phenotypes due to gonadotropin-releasing hormone (GnRH) deficiency. To date, more than 40 genes have been identified as pathogenic cause of CHH. These genes could be grouped into two major categories: genes controlling development and GnRH neuron migration and genes being responsible for neuroendocrine regulation and GnRH neuron function. High-throughput, next-generation sequencing (NGS) allows to analyze numerous gene sequences at the same time. Nowadays, whole exome or whole genome datasets could be investigated in clinical genetic diagnostics due to their favorable cost-benefit. The increasing genetic data generated by NGS reveal novel candidate genes and gene variants with unknown significance (VUSs). To provide clinically valuable genetic results, complex clinical and bioinformatics work are needed. The multifaceted genetics of CHH, the variable mode of inheritance, the incomplete penetrance, variable expressivity and oligogenic characteristics further complicate the interpretation of the genetic variants detected. The objective of this work, apart from reviewing the currently known genes associated with CHH, was to summarize the advantages and disadvantages of the NGS-based platforms and through the authors' own practice to guide through the whole workflow starting from gene panel design, performance analysis and result interpretation. Based on our results, a genetic diagnosis was clearly identified in 21% of cases tested (8/38).

The SDHB Arg230His mutation causing familial paraganglioma alters glycolysis in a new Caenorhabditis elegans model.

The conserved B-subunit of succinate dehydrogenase (SDH) participates in the tricarboxylic acid cycle (TCA) cycle and mitochondrial electron transport. The Arg230His mutation in SDHB causes heritable pheochromocytoma/paraganglioma (PPGL). In Caenorhabditiselegans, we generated an in vivo PPGL model (SDHB-1 Arg244His; equivalent to human Arg230His), which manifests delayed development, shortened lifespan, attenuated ATP production and reduced mitochondrial number. Although succinate is elevated in both missense and null sdhb-1(gk165) mutants, transcriptomic comparison suggests very different causal mechanisms that are supported by metabolic analysis, whereby only Arg244His (not null) worms demonstrate elevated lactate/pyruvate levels, pointing to a missense-induced, Warburg-like aberrant glycolysis. In silico predictions of the SDHA-B dimer structure demonstrate that Arg230His modifies the catalytic cleft despite the latter's remoteness from the mutation site. We hypothesize that the Arg230His SDHB mutation rewires metabolism, reminiscent of metabolic reprogramming in cancer. Our tractable model provides a novel tool to investigate the metastatic propensity of this familial cancer and our approach could illuminate wider SDH pathology.This article has an associated First Person interview with the first author of the paper.

Germline BRCA1 Mutation Detected in a Multiple Endocrine Neoplasia Type 2 Case With RET Codon 634 Mutation.

Coincidences of more than one pathogenic mutation in high and/or moderate risk-associated cancer genes have been rarely reported, and the implication for disease progression has been debated. We present a case harboring two autosomal dominant inherited mutations potentially aggravating the phenotype. Case report: A 16-year-old female was referred to the Endocrine Unit due to two palpable thyroid nodules and hair loss. Two hypoechoic, inhomogeneous masses with microcalcification in the thyroid gland were confirmed as medullary thyroid carcinoma. Genetic testing revealed a pathogenic heterozygous RET mutation associated with multiple endocrine neoplasia type 2 (MEN2). Furthermore, genetic screening identified the same mutation in the proband's clinically negative brother as well as in his two sons. The proband's mother and maternal aunt died of breast cancer. No samples were available from the deceased. The proband underwent further genetic counseling and BRCA1/2 testing. A novel, frameshift heterozygous BRCA1 mutation (BRCA1 p.Ile90Serfs, NC_000017.10:g.41256905_41256917) was identified in the proband, but it was absent in the brother and father, indicative of maternal inheritance. Breast or ovarian cancer was neither detected in our case at initial presentation nor during the 6-year follow-up. Conclusion: Coincidence of two monogenic autosomal dominant tumor syndromes is extremely rare, but it represents a significant therapeutic and cancer surveillance challenge. Due to the wider use of next generation sequencing in clinical practice, similar situations may occur more frequently.

Comprehensive Analysis of Circulating miRNAs in the Plasma of Patients With Pituitary Adenomas.

BACKGROUND: Circulating miRNAs in pituitary adenomas would improve patient care, especially as minimally invasive biomarkers of tumor recurrence and progression in nonfunctioning adenoma cases. AIM: Our aim was to investigate plasma miRNA profiles in patients with pituitary adenomas. MATERIALS AND METHODS: A total of 149 plasma and extracellular vesicle (preoperative, early postoperative, and late postoperative) samples were collected from 45 patients with pituitary adenomas. Adenomas were characterized on the basis of anterior pituitary hormones and transcription factors by immunostaining. miRNA next-generation sequencing was performed on 36 samples (discovery set). Individual TaqMan assays were used for validation on an extended sample set. Pituitary adenoma tissue miRNAs were evaluated by TaqMan array and data in the literature. RESULTS: Global downregulation of miRNA expression was observed in plasma samples of pituitary adenomas compared with normal samples. Expression of 29 miRNAs and isomiR variants were able to distinguish preoperative plasma samples from normal controls. miRNAs with altered expression in both plasma and different adenoma tissues were identified. Three, seven, and 66 miRNAs expressed differentially between preoperative and postoperative plasma samples in GH-secreting, FSH/LH+, and hormone-immunonegative groups, respectively. miR‒143-3p was downregulated in late postoperative but not in early postoperative plasma samples compared with preoperative ones exclusively in FSH/LH+ adenomas. The plasma level of miR‒143-3p discriminated these samples with 81.8% sensitivity and 72.3% specificity (area under the curve = 0.79; P = 0.02). CONCLUSIONS: Differentially expressed miRNAs in pituitary adenoma tissues have low abundance in plasma, minimizing their role as biomarkers. Plasma miR‒143-3p level decreased in patients with FSH/LH+ adenomas, indicating successful surgery, but its application for evaluating tumor recurrence needs further investigation.

MicroRNA Expression Profiling in Adrenal Myelolipoma.

Introduction: Adrenal myelolipoma (AML) is the second most common and invariably benign primary adrenal neoplasm. Due to the variable proportion of fat and hematopoietic elements and its often large size, it can cause differential diagnostic problems. Several reports confirmed the utility of miRNAs in the diagnosis of tumors, but miRNA expression in AML has not yet been investigated. Materials and Methods: Next-generation sequencing (NGS) was performed on 30 formalin-fixed, paraffin-embedded (FFPE) archived tissue samples [10 each of AML, adrenocortical adenoma (ACA), and adrenocortical carcinoma (ACC)]. Validation was performed by real-time quantitative reverse transcription polymerase chain reaction on a cohort containing 41 further FFPE samples (15 AML, 14 ACA, and 12 ACC samples). Circulating miRNA counterparts of significantly differentially expressed tissue miRNAs were studied in 33 plasma samples (11 each of ACA, ACC, and AML). Results: By NGS, 256 significantly differentially expressed miRNAs were discovered, and 8 of these were chosen for validation. Significant overexpression of hsa-miR-451a, hsa-miR-486-5p, hsa-miR-363-3p, and hsa-miR-150-5p was confirmed in AML relative to ACA and ACC. hsa-miR-184, hsa-miR-483-5p, and hsa-miR-183-5p were significantly overexpressed in ACC relative to ACA but not to AML. Circulating hsa-miR-451a and hsa-miR-363-3p were significantly overexpressed in AML, whereas circulating hsa-miR-483-5p and hsa-miR-483-3p were only significantly overexpressed in ACC vs ACA. Conclusions: We have found significantly differentially expressed miRNAs in AML and adrenocortical tumors. Circulating hsa-miR-451a might be a promising minimally invasive biomarker of AML. The lack of significantly different expression of hsa-miR-483-3p and hsa-miR-483-5p between AML and ACC might limit their applicability as diagnostic miRNA markers for ACC.

[Evolution of molecular genetic methods in the clinical diagnosis of hereditary endocrine tumour syndromes]. / Molekuláris genetikai vizsgálatok az örökletes endokrinológiai tumor szindrómák klinikai diagnosztikájában.

The common features of hereditary endocrine tumour syndromes or multiple endocrine neoplasias (MEN) are the association of various tumours of different endocrine organs in one patient or within the same family. Different types can be distinguished from among which type 1 and type 2 are the most common. The mode of inheritance is autosomal dominant, meaning that there is a 50% chance to inherit the pathogenic alteration. The pathogenic variants of genes responsible for MEN syndromes have also been identified in sporadic endocrine tumours and many cases initially referred to as sporadic have been later categorized as familiar based on genetic analysis. The main role of the molecular genetic analysis in these syndromes is to identify the pathogenic variant, then, after appropriate genetic counseling, to perform the genetic screening of first-degree relatives. Following molecular genetic analysis, the state-of-the-art clinical follow-up of the clinically healthy mutation carriers may decrease or even prevent the morbidity and mortality. Due to technological developments in recent years, the molecular genetic analysis of hereditary tumour syndromes has also been changed. Using next generation based sequencing methods in routine clinical diagnostics, the number of pathogenic genes in endocrine tumours has also increased. The present review focuses on the genetic background of hereditary endocrine tumour syndromes and the recently used molecular biological methods will also be presented. Orv Hetil. 2018; 159(7): 285-292.

Systematic Investigation of Expression of G2/M Transition Genes Reveals CDC25 Alteration in Nonfunctioning Pituitary Adenomas.

Dysregulation of G1/S checkpoint of cell cycle has been reported in pituitary adenomas. In addition, our previous finding showing that deregulation of Wee1 kinase by microRNAs together with other studies demonstrating alteration of G2/M transition in nonfunctioning pituitary adenomas (NFPAs) suggest that G2/M transition may also be important in pituitary tumorigenesis. To systematically study the expression of members of the G2/M transition in NFPAs and to investigate potential microRNA (miRNA) involvement. Totally, 80 NFPA and 14 normal pituitary (NP) tissues were examined. Expression of 46 genes encoding members of the G2/M transition was profiled on 34 NFPA and 10 NP samples on TaqMan Low Density Array. Expression of CDC25A and two miRNAs targeting CDC25A were validated by individual quantitative real time PCR using TaqMan assays. Protein expression of CDC25A, CDC25C, CDK1 and phospho-CDK1 (Tyr-15) was investigated on tissue microarray and immunohistochemistry. Several genes' expression alteration were observed in NFPA compared to normal tissues by transcription profiling. On protein level CDC25A and both the total and the phospho-CDK1 were overexpressed in adenoma tissues. CDC25A correlated with nuclear localized CDK1 (nCDK1) and with tumor size and nCDK1 with Ki-67 index. Comparing primary vs. recurrent adenomas we found that Ki-67 proliferation index was higher and phospho-CDK1 (inactive form) was downregulated in recurrent tumors compared to primary adenomas. Investigating the potential causes behind CDC25A overexpression we could not find copy number variation at the coding region nor expression alteration of CDC25A regulating transcription factors however CDC25A targeting miRNAs were downregulated in NFPA and negatively correlated with CDC25A expression. Our results suggest that among alterations of G2/M transition of the cell cycle, overexpression of the CDK1 and CDC25A may have a role in the pathogenesis of the NFPA and that CDC25A is potentially regulated by miRNAs.

Fluorescence activated cell sorting followed by small RNA sequencing reveals stable microRNA expression during cell cycle progression.

BACKGROUND: Previously, drug-based synchronization procedures were used for characterizing the cell cycle dependent transcriptional program. However, these synchronization methods result in growth imbalance and alteration of the cell cycle machinery. DNA content-based fluorescence activated cell sorting (FACS) is able to sort the different cell cycle phases without perturbing the cell cycle. MiRNAs are key transcriptional regulators of the cell cycle, however, their expression dynamics during cell cycle has not been explored. METHODS: Following an optimized FACS, a complex initiative of high throughput platforms (microarray, Taqman Low Density Array, small RNA sequencing) were performed to study gene and miRNA expression profiles of cell cycle sorted human cells originating from different tissues. Validation of high throughput data was performed using quantitative real time PCR. Protein expression was detected by Western blot. Complex statistics and pathway analysis were also applied. RESULTS: Beyond confirming the previously described cell cycle transcriptional program, cell cycle dependently expressed genes showed a higher expression independently from the cell cycle phase and a lower amplitude of dynamic changes in cancer cells as compared to untransformed fibroblasts. Contrary to mRNA changes, miRNA expression was stable throughout the cell cycle. CONCLUSIONS: Cell cycle sorting is a synchronization-free method for the proper analysis of cell cycle dynamics. Altered dynamic expression of universal cell cycle genes in cancer cells reflects the transformed cell cycle machinery. Stable miRNA expression during cell cycle progression may suggest that dynamical miRNA-dependent regulation may be of less importance in short term regulations during the cell cycle.

Novel SDHB and TMEM127 Mutations in Patients with Pheochromocytoma/Paraganglioma Syndrome.

Pheochromocytomas (Pheo) and paragangliomas (PGL) are rare tumors, with heterogeneous genetic background. In up to 30 % of all, apparently sporadic Pheo/PGL cases germline mutations can be identified in one of the 15 genes representing genetic susceptibility for Pheo/PGL. Malignancy is rare but it frequently associates with SDHB mutations. Our aim was to determine the prevalence of germline SDHx, SDHAF2, MAX and TMEM127 mutations in Hungarian patients with apparently sporadic Pheo/PGLs. Mutation screening of the SDHx, SDHAF2, MAX and TMEM127 genes was performed in 82 Hungarian patients with apparently sporadic Pheo/PGL using PCR and bidirectional Sanger sequencing. Disease-causing germline mutations were identified in 11 patients, of which 4 SDHB and 2 TMEM127 mutations were novel. Earlier development of Pheo/PGL, more malignant phenotype and multiple tumors were observed in genetically positive cases especially in those with SDHB mutations. The presence of bilateral or multiple tumors was the most predictive for identification of a pathogenic mutation. Together with cases harboring germline RET, VHL and NF1 mutations, Hungarian patients with Pheo/PGL exhibit a heterogeneous mutation spectrum, indicating that all of the Pheo/PGL susceptibility genes should be tested. Novel genotype-phenotype associations revealed by our study may contribute to improvement of diagnostic approaches and may help to achieve a better clinical follow up for patients with Pheo/PGL.

[Novel methods and their applicability in the evaluation of the genetic background of endocrine system tumours]. / Új módszertani lehetoségek és ezek alkalmazása a hormonális rendszer daganatainak genetikai kivizsgálásában.

The technical developments leading to revolution in clinical genetic testing offer new approaches for patients with cancer. From one mutation or one gene approach the scale of genetic testing moved to whole exome or whole genome scale. It is well known that many tumours are genetically determined and they are part of familial tumour syndromes. In addition, some mutations indicate specific molecular targeted therapies. Although sampling and sample preparation are different for testing germline and somatic mutations, the technical background of the analysis is the same. The aim of clinical genetic testing is to identify patients who are carriers of disease-causing mutations or to test tumour tissue for the presence of genetic alterations which may be targets for therapeutic approaches. In this review the authors summarize novel possibilities offered by next-generation sequencing in clinical genetic testing of patients with endocrine tumours. In addition, the authors review recent guidelines on technical and ethical issues related to these novel methods.