Scientific memory from the early nineties; a common project with professors late János Gergely and Anna Erdei.

Based on the findings of common project 29 years ago, the Scandinavian J. of Immunology accepted and published our paper entitled by "FcγR-Dependent Regulation of the Biosynthesis of Complement C3 by Murine Macrophages: the Modulatory Effect of IL-6" (Bajtay et al. in SJI 35:195-201, 1992). In this report we attempt to review the previous results and evaluate them with our current concepts on the interaction between the actors of adaptive and innate immunity. Let us first to summarize the basic results and consequences from the paper from 1992. Abstract from 1991-1992: The effect of murine IgG isotypes (myeloma proteins) on the gene expression and secretion of the third component of complement (C3) has been studied using the in monocytoid cell line P388D1 and oil-elicited mouse peritoneal macrophages. It is demonstrated that the binding of lgG2a and lgG2b but not IgGl and IgG3 isotypes augments the biosynthesis of C3 both in the presence and in the absence of the phorbol myristate acetate in the case of both cell types. The multifunctional cytokine inlerleukin-6 (IL-6) alone reveals no effect on the gene expression of C3, but facilitates the effectiveness of mouse IgG2a and IgG2b. Confirming the role of FcgRll, a strong up-regulation of gene expression and secretion of C3 was found when macrophages were co-cultured with the F(ab')2 fragment of the FcγRII-specific monoclonal antibody 2.4 G2.

Integrated Systems Biology Approach Identifies Novel Maternal and Placental Pathways of Preeclampsia.

Preeclampsia is a disease of the mother, fetus, and placenta, and the gaps in our understanding of the complex interactions among their respective disease pathways preclude successful treatment and prevention. The placenta has a key role in the pathogenesis of the terminal pathway characterized by exaggerated maternal systemic inflammation, generalized endothelial damage, hypertension, and proteinuria. This sine qua non of preeclampsia may be triggered by distinct underlying mechanisms that occur at early stages of pregnancy and induce different phenotypes. To gain insights into these molecular pathways, we employed a systems biology approach and integrated different "omics," clinical, placental, and functional data from patients with distinct phenotypes of preeclampsia. First trimester maternal blood proteomics uncovered an altered abundance of proteins of the renin-angiotensin and immune systems, complement, and coagulation cascades in patients with term or preterm preeclampsia. Moreover, first trimester maternal blood from preterm preeclamptic patients in vitro dysregulated trophoblastic gene expression. Placental transcriptomics of women with preterm preeclampsia identified distinct gene modules associated with maternal or fetal disease. Placental "virtual" liquid biopsy showed that the dysregulation of these disease gene modules originates during the first trimester. In vitro experiments on hub transcription factors of these gene modules demonstrated that DNA hypermethylation in the regulatory region of ZNF554 leads to gene down-regulation and impaired trophoblast invasion, while BCL6 and ARNT2 up-regulation sensitizes the trophoblast to ischemia, hallmarks of preterm preeclampsia. In summary, our data suggest that there are distinct maternal and placental disease pathways, and their interaction influences the clinical presentation of preeclampsia. The activation of maternal disease pathways can be detected in all phenotypes of preeclampsia earlier and upstream of placental dysfunction, not only downstream as described before, and distinct placental disease pathways are superimposed on these maternal pathways. This is a paradigm shift, which, in agreement with epidemiological studies, warrants for the central pathologic role of preexisting maternal diseases or perturbed maternal-fetal-placental immune interactions in preeclampsia. The description of these novel pathways in the "molecular phase" of preeclampsia and the identification of their hub molecules may enable timely molecular characterization of patients with distinct preeclampsia phenotypes.

HLA-DRB1*07:01-HLA-DQA1*02:01-HLA-DQB1*02:02 haplotype is associated with a high risk of asparaginase hypersensitivity in acute lymphoblastic leukemia.

Hypersensitivity reactions are the most frequent dose-limiting adverse reactions to Escherichia coli-derived asparaginase in pediatric acute lymphoblastic leukemia (ALL) patients. The aim of the present study was to identify associations between sequence-based Human Leukocyte Antigen Class II region alleles and asparaginase hypersensitivity in a Hungarian ALL population. Four-digit typing of HLA-DRB1 and HLA-DQB1 loci was performed in 359 pediatric ALL patients by using next-generation sequencing method. Based on genotypic data of the two loci, haplotype reconstruction was carried out. In order to investigate the possible role of the HLA-DQ complex, the HLA-DQA1 alleles were also inferred. Multivariate logistic regression analysis and a Bayesian network-based approach were applied to identify relevant genetic risk factors of asparaginase hypersensitivity. Patients with HLA-DRB1*07:01 and HLA-DQB1*02:02 alleles had significantly higher risk of developing asparaginase hypersensitivity compared to non-carriers [P=4.56×10-5; OR=2.86 (1.73-4.75) and P=1.85×10-4; OR=2.99 (1.68-5.31); n=359, respectively]. After haplotype reconstruction, the HLA-DRB1*07:01-HLA-DQB1*02:02 haplotype was associated with an increased risk. After inferring the HLA-DQA1 alleles the HLA-DRB1*07:01-HLA-DQA1*02:01-HLA-DQB1*02:02 haplotype was associated with the highest risk of asparaginase hypersensitivity [P=1.22×10-5; OR=5.00 (2.43-10.29); n=257]. Significantly fewer T-cell ALL patients carried the HLA-DQB1*02:02 allele and the associated haplotype than did pre-B-cell ALL patients (6.5%; vs. 19.2%, respectively; P=0.047). In conclusion, we identified a haplotype in the Human Leukocyte Antigen Class II region associated with a higher risk of asparaginase hypersensitivity. Our results confirm that variations in HLA-D region might influence the development of asparaginase hypersensitivity.

Human Fetuin-A Rs4918 Polymorphism and its Association with Obesity in Healthy Persons and in Patients with Myocardial Infarction in Two Hungarian Cohorts.

BACKGROUND Human fetuin A (AHSG) has been associated with the development of obesity, insulin resistance, type 2 diabetes mellitus, and atherosclerosis. Observations on the role of AHSG rs4918 single-nucleotide polymorphism are contradictory. We investigated the association between variants of rs4918 and parameters of obesity, lipid status, tumor necrosis factor-α (TNFα), adipokines (adiponectin, resistin, leptin), and insulin resistance in healthy persons and in patients with previous myocardial infarction. MATERIAL AND METHODS This was a cross-sectional study comprising cohort 1 (81 healthy individuals) and cohort 2 (157 patients with previous myocardial infarction). We used the allele-specific KASP genotyping assay to detect rs4918 polymorphism. RESULTS In cohort 1, G-nucleotide carriers had significantly lower serum TNFα, adiponectin, and higher leptin concentrations than in non-G carriers. These differences, however, were not observed in cohort 2. In cohort 2, G-carriers had lower BMI and waist circumferences than in non-G carriers. The G allele was more frequent among lean than obese patients (RR=1.067, 95%CI=1.053-2.651, p=0.015). An association between BMI and rs4918 polymorphism was observed among patients without diabetes (CC/CG/GG genotypes: p=0.003, G vs. non-G allele: p=0.008) but not in diabetics. In addition, a strong linearity between BMI and the CC/CG/GG genotypes (association value: 4.416, p=0.036) and the frequency of the G allele (7.420, p=0.006) could be identified. In cohort 2, non-obese, non-diabetic G-carriers still had lower BMI and waist circumferences than in non-G carriers. CONCLUSIONS The rs4918 minor variant is associated with lower TNFα and adiponectin, higher leptin levels in healthy persons, and more favorable anthropomorphic parameters of obesity in cohort 2.

Association of human fetuin-A rs4917 polymorphism with obesity in 2 cohorts.

BACKGROUND: Previous studies have shown association of the multifunctional hepatic protein α2HS-glycoprotein/human fetuin A with insulin resistance, type 2 diabetes mellitus, metabolic syndrome, obesity, and atherosclerosis. Reports of contribution of α2HS-glycoprotein/human fetuin A rs4917 single-nucleotide polymorphism to the development of these pathologic processes are inconsistent. We aimed to investigate the association between variants of rs4917 and parameters of obesity, lipid status, the proinflammatory cytokine tumor necrosis factor α (TNF-α), adipokines (adiponectin, resistin), and insulin resistance in 2 cohorts. METHODS: Eighty-one healthy persons (cohort 1) and 157 patients with previous myocardial infarction (cohort 2) were included in this cross-sectional study. rs4917 Polymorphism was determined by the allele-specific KASP by design genotyping assays. RESULTS: In cohort 1, T-nucleotide carriers had lower low-density lipoprotein cholesterol levels compared with non-T carriers. The serum concentration of TNF-α was found to be higher carrying the non-T allele in cohort 1; however, this difference was not observed in cohort 2. In cohort 2, T carriers had lower body mass index and abdominal and waist circumferences than did non-T carriers. The T nucleotide was more frequent in nonobese than in obese patients (χ = 5.217, P = 0.022). Nonobese, nondiabetic T carriers still had lower body mass index and waist circumference than did non-T carriers. CONCLUSIONS: Our data suggest that the T nucleotide in rs4917 is associated with more favorable lipid status among healthy persons (i.e., lower low-density lipoprotein cholesterol) and anthropologic parameters of obesity in cohort 2. The protective role of the T allele may also be associated with lower TNF-α levels found in healthy individuals.

MicroRNAs in adrenal tumors: relevance for pathogenesis, diagnosis, and therapy.

Several lines of evidence support the relevance of microRNAs in both adrenocortical and adrenomedullary (pheochromocytomas) tumors. Significantly differentially expressed microRNAs have been described among benign and malignant adrenocortical tumors and different forms of pheochromocytomas that might affect different pathogenic pathways. MicroRNAs can be exploited as markers of malignancy or disease recurrence. Besides tissue microRNAs, novel data show that microRNAs are released in body fluids, and blood-borne microRNAs can be envisaged as minimally invasive markers of malignancy or prognosis. MicroRNAs might even serve as treatment targets that could expand the rather-limited therapeutic repertoire in the field of adrenal tumors. In this review, we present a critical synopsis of the recent observations made in the field of adrenal tumor-associated microRNAs regarding their pathogenic, diagnostic, and potential therapeutic relevance.

Myeloid-derived microRNAs, miR-223, miR27a, and miR-652, are dominant players in myeloid regulation.

In the past few years expanding knowledge has been accumulated about the role of microRNAs (miRNAs) not only in hematopoiesis and cancer, but also in inflammatory and infectious diseases. Regarding myeloid cells, our knowledge is relatively insufficient, therefore we intended to collect the available data of miRNA profiles of myeloid cells. In addition to a rather general myeloid regulator miR-223, two other miRNAs seem to be useful subjects in understanding of myeloid miRNA biology: miR-27a and miR-652. We review functions of these three miRNAs and other myeloid miRNAs focusing on their roles in monocytes, neutrophils, eosinophils, basophils and mast cells.

Immunosuppressants increase the levels of natural autoantibodies reactive with glycosaminoglycans in myasthenia gravis.

Increasing number of evidences support the role of glycosylation in the evolution of autoimmunity. We examined carbohydrate-reactive natural autoantibodies systematically for the first time in patients with autoimmune myasthenia gravis. Antibodies reactive to glycosaminoglycans were measured with CovaLink ELISA in the sera of 59 myasthenia patients as well as in 54 healthy controls. We used the GlycoChip carbohydrate array to characterize individual carbohydrate recognition patterns. Chondroitin-sulphate C and anti-α-mannose-specific IgG levels were significantly elevated in myasthenia patients. Unexpectedly, we found that immunosuppressants increased the levels of the protective IgM glycosaminoglycan-reactive natural antibodies demonstrating a new role for these agents in immunoregulation.

Tumor formation and antitumor immunity; the overlooked significance of histamine.

HA is a biogenic amine, widely distributed throughout the body. Given the observations that HA, the decarboxylated amino acid histidine, can be induced and made available in an unstored, diffusible form in tissues undergoing rapid growth (such as tumors and regenerating tissues), it could have a role in antitumor response beyond the well-studied inflammatory and allergic responses.

Critical role of extracellular vesicles in modulating the cellular effects of cytokines.

Under physiological and pathological conditions, extracellular vesicles (EVs) are present in the extracellular compartment simultaneously with soluble mediators. We hypothesized that cytokine effects may be modulated by EVs, the recently recognized conveyors of intercellular messages. In order to test this hypothesis, human monocyte cells were incubated with CCRF acute lymphoblastic leukemia cell line-derived EVs with or without the addition of recombinant human TNF, and global gene expression changes were analyzed. EVs alone regulated the expression of numerous genes related to inflammation and signaling. In combination, the effects of EVs and TNF were additive, antagonistic, or independent. The differential effects of EVs and TNF or their simultaneous presence were also validated by Taqman assays and ELISA, and by testing different populations of purified EVs. In the case of the paramount chemokine IL-8, we were able to demonstrate a synergistic upregulation by purified EVs and TNF. Our data suggest that neglecting the modulating role of EVs on the effects of soluble mediators may skew experimental results. On the other hand, considering the combined effects of cytokines and EVs may prove therapeutically useful by targeting both compartments at the same time.

[Flow cytometry in the diagnosis of hemophagocytic lymphohistiocytosis in a case with fatal outcome]. / Az áramlási citometria jelentosége a haemophagocytás lymphohistiocytosis diagnosztikájában egy fatális kimenetelu eset bemutatása kapcsán.

Hemophagocytic lymphohistiocytosis is a multisystem inflammation, generated by the uncontrolled and excessive activation of cytotoxic T lymphocytes and natural killer cells. Severe immunodeficiency and generalized macrophage activation can often be detected in the background of this life threatening disorder. It is classified as a primary immunodeficiency. Functional abnormalities of the perforin protein or defects in granule secretory mechanisms are caused by gene mutations in most cases. Diagnostic criteria of hemophagocytic lymphohistiocytosis are the following: fever, splenomegaly, cytopenias affecting at least two of the 3 lineages in peripheral blood, hypertriglyceridemia and hyperferritinemia, elevated serum level of soluble interleukin-2 receptor (sCD25), hypofibrinogenemia, hemophagocytosis in bone marrow and decreased cytotoxic T cell and natural killer cell activity. In this case report the authors summarize the utility of functional flow cytometry in the diagnosis of hemophagocytic lymphohistiocytosis. Using flow cytometry, elevated intracellular perforin content, decreased killing activity of cytotoxic T cells and natural killer cells, and impaired cell surface expression of CD107a (LAMP1 protein) from in vitro stimulated blood lymphocytes were detected. Abnormal secretion of perforin was also demonstrated. Genetic testing revealed mutation of the MUNC 13-4 gene, which confirmed the base of the abnormal flow cytometric findings. This case report demonstrates the value of functional flow cytometry in the rapid diagnosis of genetically determined hemophagocytic lymphohistiocytosis, a condition in which early diagnosis is critical for optimal management. The authors emphasize the significance of functional flow cytometry in the differential diagnosis of immunodeficiencies.

Transcriptome profile of the murine macrophage cell response to Candida parapsilosis.

Candida parapsilosis is a human fungal pathogen with increasing global significance. Understanding how macrophages respond to C. parapsilosis at the molecular level will facilitate the development of novel therapeutic paradigms. The complex response of murine macrophages to infection with C. parapsilosis was investigated at the level of gene expression using an Agilent mouse microarray. We identified 155 and 511 differentially regulated genes at 3 and 8h post-infection, respectively. Most of the upregulated genes encoded molecules involved in immune response and inflammation, transcription, signaling, apoptosis, cell cycle, electron transport and cell adhesion. Typical of the classically activated macrophages, there was significant upregulation of genes coordinating the production of inflammatory cytokines such as TNF, IL-1 and IL-15. Further, we used both primary murine macrophages and macrophages differentiated from human peripheral mononuclear cells to confirm the upregulation of the TNF-receptor family member TNFRSF9 that is associated with Th1 T-helper cell responses. Additionally, the microarray data indicate significant differences between the response to C. parapsilosis infection and that of C. albicans.

Antitumoral effects of 9-cis retinoic acid in adrenocortical cancer.

The currently available medical treatment options of adrenocortical cancer (ACC) are limited. In our previous meta-analysis of adrenocortical tumor genomics data, ACC was associated with reduced retinoic acid production and retinoid X receptor-mediated signaling. Our objective has been to study the potential antitumoral effects of 9-cis retinoic acid (9-cisRA) on the ACC cell line NCI-H295R and in a xenograft model. Cell proliferation, hormone secretion, and gene expression have been studied in the NCI-H295R cell line. A complex bioinformatics approach involving pathway and network analysis has been performed. Selected genes have been validated by real-time qRT-PCR. Athymic nude mice xenografted with NCI-H295R have been used in a pilot in vivo xenograft model. 9-cisRA significantly decreased cell viability and steroid hormone secretion in a concentration- and time-dependent manner in the NCI-H295R cell line. Four major molecular pathways have been identified by the analysis of gene expression data. Ten genes have been successfully validated involved in: (1) steroid hormone secretion (HSD3B1, HSD3B2), (2) retinoic acid signaling (ABCA1, ABCG1, HMGCR), (3) cell-cycle damage (GADD45A, CCNE2, UHRF1), and the (4) immune response (MAP2K6, IL1R2). 9-cisRA appears to directly regulate the cell cycle by network analysis. 9-cisRA also reduced tumor growth in the in vivo xenograft model. In conclusion, 9-cisRA might represent a promising new candidate in the treatment of hormone-secreting adrenal tumors and adrenocortical cancer.

Improved circulating microparticle analysis in acid-citrate dextrose (ACD) anticoagulant tube.

INTRODUCTION: Recently extracellular vesicles (exosomes, microparticles also referred to as microvesicles and apoptotic bodies) have attracted substantial interest as potential biomarkers and therapeutic vehicles. However, analysis of microparticles in biological fluids is confounded by many factors such as the activation of cells in the blood collection tube that leads to in vitro vesiculation. In this study we aimed at identifying an anticoagulant that prevents in vitro vesiculation in blood plasma samples. MATERIALS AND METHODS: We compared the levels of platelet microparticles and non-platelet-derived microparticles in platelet-free plasma samples of healthy donors. Platelet-free plasma samples were isolated using different anticoagulant tubes, and were analyzed by flow cytometry and Zymuphen assay. The extent of in vitro vesiculation was compared in citrate and acid-citrate-dextrose (ACD) tubes. RESULTS: Agitation and storage of blood samples at 37 °C for 1 hour induced a strong release of both platelet microparticles and non-platelet-derived microparticles. Strikingly, in vitro vesiculation related to blood sample handling and storage was prevented in samples in ACD tubes. Importantly, microparticle levels elevated in vivo remained detectable in ACD tubes. CONCLUSIONS: We propose the general use of the ACD tube instead of other conventional anticoagulant tubes for the assessment of plasma microparticles since it gives a more realistic picture of the in vivo levels of circulating microparticles and does not interfere with downstream protein or RNA analyses.

Roles of genetic polymorphisms in the folate pathway in childhood acute lymphoblastic leukemia evaluated by Bayesian relevance and effect size analysis.

In this study we investigated whether polymorphisms in the folate pathway influenced the risk of childhood acute lymphoblastic leukemia (ALL) or the survival rate of the patients. For this we selected and genotyped 67 SNPs in 15 genes in the folate pathway in 543 children with ALL and 529 controls. The results were evaluated by gender adjusted logistic regression and by the Bayesian network based Bayesian multilevel analysis of relevance (BN-BMLA) methods. Bayesian structure based odds ratios for the relevant variables and interactions were also calculated. Altogether 9 SNPs in 8 genes were associated with altered susceptibility to ALL. After correction for multiple testing, two associations remained significant. The genotype distribution of the MTHFD1 rs1076991 differed significantly between the ALL and control population. Analyzing the subtypes of the disease the GG genotype increased only the risk of B-cell ALL (p = 3.52×10(-4); OR = 2.00). The GG genotype of the rs3776455 SNP in the MTRR gene was associated with a significantly reduced risk to ALL (p = 1.21×10(-3); OR = 0.55), which resulted mainly from the reduced risk to B-cell and hyperdiploid-ALL. The TC genotype of the rs9909104 SNP in the SHMT1 gene was associated with a lower survival rate comparing it to the TT genotype (80.2% vs. 88.8%; p = 0.01). The BN-BMLA confirmed the main findings of the frequentist-based analysis and showed structural interactional maps and the probabilities of the different structural association types of the relevant SNPs especially in the hyperdiploid-ALL, involving additional SNPs in genes like TYMS, DHFR and GGH. We also investigated the statistical interactions and redundancies using structural model properties. These results gave further evidence that polymorphisms in the folate pathway could influence the ALL risk and the effectiveness of the therapy. It was also shown that in gene association studies the BN-BMLA could be a useful supplementary to the traditional frequentist-based statistical method.

Comparative analysis of IL6 and IL6 receptor gene polymorphisms in mastocytosis.

Mastocytosis is a rare disease with reported high interleukin-6 (IL6) levels influencing disease severity. The present study investigated polymorphisms within the genes that encode IL6 and its receptor (IL6R) in relation to mastocytosis development in a case-control design. Analysis of the IL6R Asp358Ala polymorphism showed that carriers of the AA genotype had a 2·5-fold lower risk for mastocytosis than those with the AC or CC genotypes. No association with mastocytosis was found for the IL6-174G/C polymorphism, however, it may influence the effect of IL6R polymorphism. To the best of our knowledge this is the first study analysing IL6/IL6R polymorphisms in mastocytosis.

Candidate gene association study in pediatric acute lymphoblastic leukemia evaluated by Bayesian network based Bayesian multilevel analysis of relevance.

BACKGROUND: We carried out a candidate gene association study in pediatric acute lymphoblastic leukemia (ALL) to identify possible genetic risk factors in a Hungarian population. METHODS: The results were evaluated with traditional statistical methods and with our newly developed Bayesian network based Bayesian multilevel analysis of relevance (BN-BMLA) method. We collected genomic DNA and clinical data from 543 children, who underwent chemotherapy due to ALL, and 529 healthy controls. Altogether 66 single nucleotide polymorphisms (SNPs) in 19 candidate genes were genotyped. RESULTS: With logistic regression, we identified 6 SNPs in the ARID5B and IKZF1 genes associated with increased risk to B-cell ALL, and two SNPs in the STAT3 gene, which decreased the risk to hyperdiploid ALL. Because the associated SNPs were in linkage in each gene, these associations corresponded to one signal per gene. The odds ratio (OR) associated with the tag SNPs were: OR = 1.69, P = 2.22x10(-7) for rs4132601 (IKZF1), OR = 1.53, P = 1.95x10(-5) for rs10821936 (ARID5B) and OR = 0.64, P = 2.32x10(-4) for rs12949918 (STAT3). With the BN-BMLA we confirmed the findings of the frequentist-based method and received additional information about the nature of the relations between the SNPs and the disease. E.g. the rs10821936 in ARID5B and rs17405722 in STAT3 showed a weak interaction, and in case of T-cell lineage sample group, the gender showed a weak interaction with three SNPs in three genes. In the hyperdiploid patient group the BN-BMLA detected a strong interaction among SNPs in the NOTCH1, STAT1, STAT3 and BCL2 genes. Evaluating the survival rate of the patients with ALL, the BN-BMLA showed that besides risk groups and subtypes, genetic variations in the BAX and CEBPA genes might also influence the probability of survival of the patients. CONCLUSIONS: In the present study we confirmed the roles of genetic variations in ARID5B and IKZF1 in the susceptibility to B-cell ALL. With the newly developed BN-BMLA method several gene-gene, gene-phenotype and phenotype-phenotype connections were revealed. We showed several advantageous features of the new method, and suggested that in gene association studies the BN-BMLA might be a useful supplementary to the traditional frequentist-based statistical method.

Integrative analysis of neuroblastoma and pheochromocytoma genomics data.

BACKGROUND: Pheochromocytoma and neuroblastoma are the most common neural crest-derived tumors in adults and children, respectively. We have performed a large-scale in silico analysis of altogether 1784 neuroblastoma and 531 pheochromocytoma samples to establish similarities and differences using analysis of mRNA and microRNA expression, chromosome aberrations and a novel bioinformatics analysis based on cooperative game theory. METHODS: Datasets obtained from Gene Expression Omnibus and ArrayExpress have been subjected to a complex bioinformatics analysis using GeneSpring, Gene Set Enrichment Analysis, Ingenuity Pathway Analysis and own software. RESULTS: Comparison of neuroblastoma and pheochromocytoma with other tumors revealed the overexpression of genes involved in development of noradrenergic cells. Among these, the significance of paired-like homeobox 2b in pheochromocytoma has not been reported previously. The analysis of similar expression patterns in neuroblastoma and pheochromocytoma revealed the same anti-apoptotic strategies in these tumors. Cancer regulation by stathmin turned out to be the major difference between pheochromocytoma and neuroblastoma. Underexpression of genes involved in neuronal cell-cell interactions was observed in unfavorable neuroblastoma. By the comparison of hypoxia- and Ras-associated pheochromocytoma, we have found that enhanced insulin like growth factor 1 signaling may be responsible for the activation of Src homology 2 domain containing transforming protein 1, the main co-factor of RET. Hypoxia induced factor 1α and vascular endothelial growth factor signaling included the most prominent gene expression changes between von Hippel-Lindau- and multiple endocrine neoplasia type 2A-associated pheochromocytoma. CONCLUSIONS: These pathways include previously undescribed pathomechanisms of neuroblastoma and pheochromocytoma and associated gene products may serve as diagnostic markers and therapeutic targets.

[Relevance of long non-coding RNAs in tumour biology]. / A hosszú, nem kódoló RNS-ek jelentosége a daganatbiológiában.

The discovery of the biological relevance of non-coding RNA molecules represents one of the most significant advances in contemporary molecular biology. It has turned out that a major fraction of the non-coding part of the genome is transcribed. Beside small RNAs (including microRNAs) more and more data are disclosed concerning long non-coding RNAs of 200 nucleotides to 100 kb length that are implicated in the regulation of several basic molecular processes (cell proliferation, chromatin functioning, microRNA-mediated effects, etc.). Some of these long non-coding RNAs have been associated with human tumours, including H19, HOTAIR, MALAT1, etc., the different expression of which has been noted in various neoplasms relative to healthy tissues. Long non-coding RNAs may represent novel markers of molecular diagnostics and they might even turn out to be targets of therapeutic intervention.

Effects of mitotane on gene expression in the adrenocortical cell line NCI-H295R: a microarray study.

AIM: The adrenolytic agent mitotane is widely used in the treatment of adrenocortical cancer; however, its mechanism of action is poorly elucidated. We have studied mitotane-induced mRNA expression changes in the NCI-H295R adrenocortical cancer cell line. MATERIALS & METHODS: Cell viability and hormone assays were used to select the optimal mitotane concentration effectively inhibiting hormone secretion without affecting cell viability. RNA isolated from cultures treated for 48 and 72 h was subjected to Agilent 4×44K microarray platforms. Microarray results were validated by quantitative reverse-transcription PCR. RESULTS: Altogether, 117 significantly differentially expressed genes were detected at 48 h and 72 h (p < 0.05) in mitotane-treated samples relative to controls. Three significantly underexpressed genes involved in steroid hormone biosynthesis (HSD3B1, HSD3B2 and CYP21A2) and four significantly overexpressed genes (GDF15, ALDH1L2, TRIB3 and SERPINE2) have been validated. CONCLUSION: Gene-expression changes might be involved in the adrenal action of mitotane and in the inhibition of hormone secretion.