Neurotrophin Signaling Pathway Research Articles

High-Frequency Repetitive Magnetic Stimulation Enhances the Expression of Brain-Derived Neurotrophic Factor Through Activation of Ca2+-Calmodulin-Dependent Protein Kinase II-cAMP-Response Element-Binding Protein Pathway.

Repetitive transcranial magnetic stimulation (rTMS) can be used in various neurological disorders. However, neurobiological mechanism of rTMS is not well known. Therefore, in this study, we examined the global gene expression patterns depending on different frequencies of repetitive magnetic stimulation (rMS) in both undifferentiated and differentiated Neuro-2a cells to generate a comprehensive view of the biological mechanisms. The Neuro-2a cells were randomly divided into three groups—the sham (no active stimulation) group, the low-frequency (0.5 Hz stimulation) group, and high-frequency (10 Hz stimulation) group—and were stimulated 10 min for 3 days. The low- and high-frequency groups of rMS on Neuro-2a cells were characterized by transcriptome array. Differentially expressed genes were analyzed using the Database of Annotation Visualization and Integrated Discovery program, which yielded a Kyoto Encyclopedia of Genes and Genomes pathway. Amphetamine addiction pathway, circadian entrainment pathway, long-term potentiation (LTP) pathway, neurotrophin signaling pathway, prolactin signaling pathway, and cholinergic synapse pathway were significantly enriched in high-frequency group compared with low-frequency group. Among these pathways, LTP pathway is relevant to rMS, thus the genes that were involved in LTP pathway were validated by quantitative real-time polymerase chain reaction and western blotting. The expression of glutamate ionotropic receptor N-methyl d-aspartate 1, calmodulin-dependent protein kinase II (CaMKII) δ, and CaMKIIα was increased, and the expression of CaMKIIγ was decreased in high-frequency group. These genes can activate the calcium (Ca2+)–CaMKII–cAMP-response element-binding protein (CREB) pathway. Furthermore, high-frequency rMS induced phosphorylation of CREB, brain-derived neurotrophic factor (BDNF) transcription via activation of Ca2+–CaMKII–CREB pathway. In conclusion, high-frequency rMS enhances the expression of BDNF by activating Ca2+–CaMKII–CREB pathway in the Neuro-2a cells. These findings may help clarify further therapeutic mechanisms of rTMS.

Systematically analyses of the common dysregulated networks to understand the common pathologies between T2D and atherosclerosis

BackgroundDiabetic macroangiopathy, atherosclerosis secondary to diabetes mellitus, causes cerebro-cardiovascular diseases (CVD), which increase the risk of death in patients with DM and significantly reduce their quality of life. Therefore, mechanisms underlying the common shared pathologies between type 2 diabetes (T2D) and atherosclerosis are key to prevention and treatment of diabetic macroangiopathy. However, the common shared pathological links between T2D and atherosclerosis are not fully understood. MethodsWe constructed a T2D and atherosclerosis associated protein interaction sub-network (TAN) to investigate common shared mechanisms between T2D and atherosclerosis. In addition, MCODE plugin of Cytoscape was applied to TAN to identify most significant functional modules. The network modules were further mapped to KEGG pathway enrichment analysis. Finally, we established a miRNA-gene regulatory network by searching disease associated miRNAs and integrated them into miRNA-gene interaction network for each module. ResultsTAN contains 1230 nodes which represent the union of T2D and atherosclerosis related genes and 3683 edges which represent the interactions of gene pairs. MCODE plugin was applied and five most significant modular clusters were identified. KEGG analysis of functional modules showed these genes were involved in several pathways including type 2 diabetes mellitus, ErbB and neurotrophin signaling pathway. miRNAgene interaction network was established and these miRNA-gene interactions mediated common shared pathologies between T2D and atherosclerosis. ConclusionsAnalysis of TAN demonstrated that modular organization of the interaction network elucidates shared pathologies of T2D and atherosclerosis. Furthermore, the disease associated miRNA-gene interaction network enriched our insight into role of miRNAs in mediating common shared pathologies between T2D and atherosclerosis. Thus, miRNAs constitute attractive targets for the development of novel therapies for treating both T2D and atherosclerosis.

Molecular mechanism of Bupleuri Radix and Scutellariae Radix drug pair for depression based on integrative pharmacology platform of traditional Chinese medicine

Xiaochaihu decoction is a classic prescription of traditional Chinese medicine. Modern research has proved its anti-depression effect. However, its pharmacological mechanism for anti-depression effect is difficult to be unveiled because of the complexity of compound Chinese medicines. Bupleuri Radix and Scutellariae Radix is the core drug pair of Xiaochaihu decoction. In this research, Bupleuri Radix and Scutellariae Radix were analyzed by the integrative pharmacology platform to study its molecular mechanism for anti-depression. One hundred and sixteen active ingredients were predicted, 62 for Bupleuri Radix, mainly including saikosaponins, acids, alcohols, and 54 for Scutellariae Radix, mainly including flavonoids and glycosides. Its anti-depression effect was relevant to 118 core targets, including 22 known disease targets, such as serotonin receptor(HTR2C), activating transcription factor(ATF1, ATF2), δ opioid receptor(OPRD1), μ opioid receptor (OPRM1), κ opioid receptor(OPRK1), inositol monophosphatase(IMPA1), Toll-like receptor 4 (TLR4), histamine H1 receptor(HRH1), neurotrophic factor tyrosine kinase receptor1 (NTRK1), Glycogen synthetase kinase 3β(GSK3β), etc. The antidepressant effect involved positive regulation of transcription from RNA polymerase Ⅱ promoter, transcription factor binding, cytosol, transcriptional regulation of DNA template, enzyme binding, endocrine system, nervous system, neurotrophin signaling pathway, cell growth and death, signal transduction, thyroid hormone signaling pathway and other related biological processes and metabolic pathways. This study provides a scientific evidence for further study of the anti-depression mechanism of this drug pair.

Study on Yueju Wan for "different diseases with same treatment" based on integrative pharmacology

The traditional Chinese medicine prescription Yueju Wan has the function of regulating qi-flowing for activating stagnancy and resolving food stagnation, which is now used for the treatment of depression and gastrointestinal related diseases. In this study, an integrative pharmacological method was adopted to predict the targets and pathways of Yueju Wan and explore its molecular mechanism for depression and gastrointestinal dysfunction with the same treatment. First, disease targets were collected from Human Phenotype Ontology database, 201 targets related to depression and 474 targets related to gastrointestinal dysfunction, including 95 common targets of these two. Then, the integrative pharmacology platform of traditional Chinese medicine (TCMIP) was used to predict and analyze the drug targets, GO function, KEGG pathway, core targets network of Yueju Wan and heterogeneous network of TCM-chemical components-key drug targets-pathway. According to the integrative analysis, it is found that ATP1A1, KRAS, and PRKAA1 were key targets, and neuron apoptotic process, neurotrophin signaling pathway, serotonergic synapse and regulation of nitric-oxide synthase activity were key pathways which played important roles in molecular mechanism of Yueju Wan for depression and gastrointestinal dysfunction. In conclusion, speculated serotonergic synapse and regulation of nitric-oxide synthase activity maybe the common process in depression and gastrointestinal dysfunction. This paper provided an overall understanding on Yueju Wan based on TCMIP, helping to elucidate the mechanism of the same treatment for different diseases, depression and gastrointestinal dysfunction.

Regulation of Brain-Derived Neurotrophic Factor and Growth Factor Signaling Pathways by Tyrosine Phosphatase Shp2 in the Retina: A Brief Review.

SH2 domain-containing tyrosine phosphatase-2 (PTPN11 or Shp2) is a ubiquitously expressed protein that plays a key regulatory role in cell proliferation, differentiation and growth factor (GF) signaling. This enzyme is well expressed in various retinal neurons and has emerged as an important player in regulating survival signaling networks in the neuronal tissues. The non-receptor phosphatase can translocate to lipid rafts in the membrane and has been implicated to regulate several signaling modules including PI3K/Akt, JAK-STAT and Mitogen Activated Protein Kinase (MAPK) pathways in a wide range of biochemical processes in healthy and diseased states. This review focuses on the roles of Shp2 phosphatase in regulating brain-derived neurotrophic factor (BDNF) neurotrophin signaling pathways and discusses its cross-talk with various GF and downstream signaling pathways in the retina.

Genome-wide association study in Finnish twins highlights the connection between nicotine addiction and neurotrophin signaling pathway.

The heritability of nicotine dependence based on family studies is substantial. Nevertheless, knowledge of the underlying genetic architecture remains meager. Our aim was to identify novel genetic variants responsible for interindividual differences in smoking behavior. We performed a genome‐wide association study on 1715 ever smokers ascertained from the population‐based Finnish Twin Cohort enriched for heavy smoking. Data imputation used the 1000 Genomes Phase I reference panel together with a whole genome sequence‐based Finnish reference panel. We analyzed three measures of nicotine addiction—smoking quantity, nicotine dependence and nicotine withdrawal. We annotated all genome‐wide significant SNPs for their functional potential. First, we detected genome‐wide significant association on 16p12 with smoking quantity (P = 8.5 × 10−9), near CLEC19A. The lead‐SNP stands 22 kb from a binding site for NF‐κB transcription factors, which play a role in the neurotrophin signaling pathway. However, the signal was not replicated in an independent Finnish population‐based sample, FINRISK (n = 6763). Second, nicotine withdrawal showed association on 2q21 in an intron of TMEM163 (P = 2.1 × 10−9), and on 11p15 (P = 6.6 × 10−8) in an intron of AP2A2, and P = 4.2 × 10−7 for a missense variant in MUC6, both involved in the neurotrophin signaling pathway). Third, association was detected on 3p22.3 for maximum number of cigarettes smoked per day (P = 3.1 × 10−8) near STAC. Associating CLEC19A and TMEM163 SNPs were annotated to influence gene expression or methylation. The neurotrophin signaling pathway has previously been associated with smoking behavior. Our findings further support the role in nicotine addiction.

A six-long non-coding RNA signature predicts prognosis in melanoma patients.

The aim of this study was to identify long non-coding RNAs (lncRNAs) which may prove useful for risk-classifying patients with melanoma. For this purpose, based on a dataset from The Cancer Genome Atlas (TCGA), we selected and analyzed samples from melanoma stages I, II, III and IV, from which differentially expressed lncRNAs were identified. The lncRNAs were classified using two-way hierarchical clustering analysis and analysis of support vector machine (SVM), followed by Kaplan-Meier survival analysis. The prognostic capacity of the signature was verified on an independent dataset. lncRNA-mRNA networks were built using signature lncRNAs and corresponding target genes. The Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis was conducted on the target genes. A total of 48 differentially expressed lncRNAs were identified, from which 6 signature lncRNAs (AL050303 and LINC00707, LINC01324, RP11-85G21, RP4-794I6.4 and RP5-855F16) were identified. Two-way hierarchical clustering analysis revealed that the accuracy of the six-lncRNA signature in risk-stratifying samples was 84.84%, and the accuracy of the SVM classifier was 85.9%. This predictive signature performed well on the validation dataset [accuracy, 86.76; area under the ROC curve (AUROC), 0.816]. A total of 720 target genes of the 6 lncRNAs were selected for the lncRNA-mRNA networks. These genes were significantly related to mitogen-activated protein kinase (MAPK), the neurotrophin signaling pathway, focal adhesion pathways, and several immune and inflammation-related pathways. On the whole, we identified a six-lncRNA prognostic signature for risk-stratifying patients with melanoma. These lncRNAs may affect prognosis by regulating the MAPK pathway, immune and inflammation-related pathways, the neurotrophin signaling pathway and focal adhesion pathways.

Changed immune and miRNA response in RAW264.7 cells infected with cell wall deficient mycobacterium tuberculosis.

Cell wall deficient (CWD) forms of Mycobacterium tuberculosis (Mtb) confers a marked resistance to immune system of the host. However, there is limit data on the effect of intracellular CWD-Mtb infection on macrophages. In the study, effects of CWD-Mtb on cell viability, cytokine response and miRNA expression of macrophages were analyzed. Cell viability was reduced, levels of interleukin-1α(IL-1α), IL-1β, IL-6, IL-10 and interferon-γ (IFN-γ) were also significantly changed after infection of RAW264.7 cells with CWD-Mtb. A total of 105miRNAs were deregulated between CWD-Mtb and wild Mtb group, and among them, miR-29b was upregulated in CWD-Mtb group. Downregulation of miR-29b resulted in significant elevation level of IFN-γ mRNA. Involved signaling pathways of potential target genes of differentially expressed miRNAs mainly focused on Tcell receptor signaling pathway, MAPK signaling pathway, neurotrophin signaling pathway, and regulation of actin cytoskeleton. Taken together, the results showed that cytokine production of CWD-Mtb infected macrophages was altered and many miRNAs were involved in regulation of macrophage response to CWD-Mtb infection, which probably determined the differential outcome following different phenotype Mtb infection. These findings open up a new and interesting avenue for an improved understanding of pathogenesis of CWD-Mtb.

Integrated analysis of gene expression signatures associated with colon cancer from three datasets

PurposeThe present study aimed to elucidate the pathogenesis of colon cancer and identify genes associated with tumor development. MethodsThree datasets, two (GSE74602 and GSE44861) from the Gene Expression Omnibus database and RNA-Seq colon cancer data from The Cancer Genome Atlas data portal, were downloaded. These three datasets were grouped using a meta-analysis approach, and differentially expressed genes (DEGs) were identified between colon tumor samples and adjacent normal samples. Functional enrichment analysis and regulatory factor predication were performed for significant genes. Additionally, small-molecule drugs associated with colon cancer were predicted, and a prognostic risk model was constructed. ResultsThere were 251 overlapping DEGs (135 up- and 116 downregulated) between cancer samples and control samples in the three datasets. The DEGs were mainly involved in protein transport and apoptotic and neurotrophin signaling pathways. A total of 70 small-molecule drugs were predicated to be associated with colon cancer. Additionally, in the miRNA–target regulatory network, we found that SLC44A1 can be targeted by hsa-miR-183, hsa-miR-206, and hsa-miR-147, while KLF13 can be regulated by hsa-miR-182, hsa-miR-206, and hsa-miR-153. Moreover, the results of the prognostic risk model showed that four genes (VAMP1, P2RX5, CACNB1, and CRY2) could divide the samples into high and low risk groups. ConclusionSLC44A1 and KLF13 may be involved in tumorigenesis and the metastasis of colon cancer by miRNA regulation. In addition, a four-gene (VAMP1, P2RX5, CACNB1, and CRY2) expression signature may have prognostic and predictive value in colon cancer.

Targetome Analysis Revealed Involvement of MiR-126 in Neurotrophin Signaling Pathway: A Possible Role in Prevention of Glioma Development.

Objective For the first time, we used molecular signaling pathway enrichment analysis to determine possible involvement of miR-126 and IRS-1 in neurotrophin pathway. Materials and Methods In this prospective study, validated and predicted targets (targetome) of miR-126 were collected following searching miRtarbase (http://mirtarbase.mbc.nctu.edu.tw/) and miRWalk 2.0 databases, respectively. Then, approximate expression of miR-126 targeting in Glioma tissue was examined using UniGene database (http://www.ncbi. nlm.nih.gov/unigene). In silico molecular pathway enrichment analysis was carried out by DAVID 6.7 database (http://david. abcc.ncifcrf.gov/) to explore which signaling pathway is related to miR-126 targeting and how miR-126 attributes to glioma development. Results MiR-126 exerts a variety of functions in cancer pathogenesis via suppression of expression of target gene including PI3K, KRAS, EGFL7, IRS-1 and VEGF. Our bioinformatic studies implementing DAVID database, showed the involvement of miR-126 target genes in several signaling pathways including cancer pathogenesis, neurotrophin functions, Glioma formation, insulin function, focal adhesion production, chemokine synthesis and secretion and regulation of the actin cytoskeleton. ConclusionTaken together, we concluded that miR-126 enhances the formation of glioma cancer stem cell probably via down regulation of IRS-1 in neurotrophin signaling pathway.

Potential Diagnostic Power of Blood Circular RNA Expression in Active Pulmonary Tuberculosis

BackgroundCircular RNAs (circRNAs) are a class of novel RNAs with important biological functions, and aberrant expression of circRNAs has been implicated in human diseases. However, the feasibility of using blood circRNAs as disease biomarkers is largely unknown. MethodsWe explored the potential of using human peripheral blood mononuclear cell (PBMC) circRNAs as marker molecules to diagnose active pulmonary tuberculosis (TB). FindingsFirst, we demonstrated that circRNAs are widely expressed in human PBMCs and that many are abundant enough to be detected. Second, we found that the magnitude of PBMC circRNAs in TB patients was higher than that in the paired healthy controls. Compared with host linear transcripts, the circRNAs within several pathways are disproportionately upregulated in active TB patients, including “Cytokine-cytokine receptor interaction”, “Chemokine signaling pathway”, “Neurotrophin signaling pathway”, and “Bacterial invasion of epithelial cells”. Based on the differentially expressed circRNAs within these pathways, we developed a PBMC circRNA-based molecular signature differentiating active TB patients from healthy controls. We validated the classification power of the PBMC circRNA signature in an independent cohort with the area under the receiver operating characteristic curve (AUC) at 0.946. InterpretationOur results suggest that PBMC circRNAs are potentially reliable marker molecules in TB diagnosis.

Differential exosomal microRNA profile in the serum of a patient with depression

Background and objectivesAccumulating evidence suggests that exosomal miRNAs play important roles in disease pathogenesis; however, their role in the pathogenesis of depression remains largely unknown. We explored the miRNA profile of circulating exosomes in a patient with depression and compared it with a healthy volunteer. MethodsSerum exosomes were isolated from a patient and volunteer, and exosomal miRNAs were analyzed by miRNA-sequencing. MiRTarbase and gene ontology (GO) analysis were used to predict the downstream signaling pathways of the depression-specific miRNAs. ResultsmiRNA-sequencing analysis identified 12 up-regulated miRNAs and 20 down-regulated miRNAs in the depressed patient. MiRTarbase and GO analysis revealed that the up-regulated miRNAs regulated the expression of genes involved in histone/chromatin modification and the neurotrophin signaling pathway. The down-regulated miRNAs regulated genes were associated with apoptosis, hypoxia, cell growth, and immune response. ConclusionsDepression-specific miRNAs may modulate neurotrophin signaling, chromatin/histone modification, immune system function, inflammation, depression, apoptosis, hypoxia, and cell growth. Identifying the networks that may be regulated by these depression-specific miRNAs and their target genes may provide a novel, high-throughput screening platform for the early detection of depression as well as determining its severity and response to treatment.

Stress amplifies sex differences in primate prefrontal profiles of gene expression

BackgroundStress is a recognized risk factor for mood and anxiety disorders that occur more often in women than men. Prefrontal brain regions mediate stress coping, cognitive control, and emotion. Here, we investigate sex differences and stress effects on prefrontal cortical profiles of gene expression in squirrel monkey adults.MethodsDorsolateral, ventrolateral, and ventromedial prefrontal cortical regions from 18 females and 12 males were collected after stress or no-stress treatment conditions. Gene expression profiles were acquired using HumanHT-12v4.0 Expression BeadChip arrays adapted for squirrel monkeys.ResultsExtensive variation between prefrontal cortical regions was discerned in the expression of numerous autosomal and sex chromosome genes. Robust sex differences were also identified across prefrontal cortical regions in the expression of mostly autosomal genes. Genes with increased expression in females compared to males were overrepresented in mitogen-activated protein kinase and neurotrophin signaling pathways. Many fewer genes with increased expression in males compared to females were discerned, and no molecular pathways were identified. Effect sizes for sex differences were greater in stress compared to no-stress conditions for ventromedial and ventrolateral prefrontal cortical regions but not dorsolateral prefrontal cortex.ConclusionsStress amplifies sex differences in gene expression profiles for prefrontal cortical regions involved in stress coping and emotion regulation. Results suggest molecular targets for new treatments of stress disorders in human mental health.

The protective value of miR-204-5p for prognosis and its potential gene network in various malignancies: a comprehensive exploration based on RNA-seq high-throughput data and bioinformatics.

PurposeThe prognostic role of miR-204-5p (previous ID: miR-204) is varied and inconclusive in diverse types of malignant neoplasm. Therefore, the purposes of the study comprehensively explore the overall prognostic role of miR-204-5p based on high-throughput microRNA sequencing data, and to investigate the potential role of miR-204-5p via bioinformatics approaches.Materials and MethodsThe data of microRNA sequencing and survival were downloaded from The Cancer Genome Atlas (TCGA), and the prognostic value of miR-204-5p was analyzed by using Kaplan-Meier and univariate cox regressions. Then a meta-analysis was conducted with all TCGA data and relevant studies collected from literature. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. The prospective molecular mechanism of miR-204-5p was also assessed at a functional level with Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-to-protein interactions (PPI) network.ResultsFrom TCGA data, the prognostic value of miR-204-5p obviously varied among 20 types of cancers. The pooled HR was 0.928 (95% CI: 0.774–1.113, P = 0.386, 6203 cases of malignancies). For the meta-analysis based on 15 studies from literature, the pooled HR was 0.420 (95% CI: 0.306–0.576, P < 0.001, 1783 cases of malignancies) for overall survival (OS). Furthermore, the combined HR from both TCGA and literature was 0.708 (95% CI: 0.600–0.834, P < 0.001, 7986 cases of malignancies). Subgroup analyses revealed that miR-204-5p could act as a prognostic marker in cancers of respiratory system and digestive system. Functional analysis was conducted on genes predicted as targets (n = 2057) after the overlay genes from six out of twelve software were extracted. Two significant KEGG pathways were enriched (hsa04360: Axon guidance and hsa04722: Neurotrophin signaling pathway). PPI network revealed some hub genes/proteins (CDC42, SOS1, PIK3R1, MAPK1, PLCG1, ESR1, MAPK11, and AR).ConclusionsThe current study demonstrates that over-expression of miR-204-5p could be a protective factor for a certain group of cancers. Clinically, the low miR-204-5p level could gain a predictive value for a poor survival in cancers of respiratory system and digestive system. The detailed molecular mechanisms of miR-204-5p remain to be verified.

IL-17 Exerts Anti-Apoptotic Effect via miR-155-5p Downregulation in Experimental Autoimmune Encephalomyelitis

Multiple sclerosis is an autoimmune, neurodegenerative disease, affecting mostly young adults and resulting in progressive disability. It is a multifactorial disorder, with important involvement of both cellular and epigenetic components. Among the epigenetic factors, microRNAs are currently intensively investigated in the context of multiple sclerosis. It has been shown that their biogenesis and function may be regulated by various cytokines. IL-17, a hallmark cytokine of Th17 cells, has been thought to function predominantly as a pro-inflammatory factor, leading to increased disease symptoms. However, there are several studies indicating its protective role during inflammatory process. In this work, we have assessed the impact of high-dose IL-17 administration on microRNAs’ expression profile during the preclinical stage of EAE. For selected microRNA, we have performed computational analysis of its potential target mRNAs and cellular pathways. Based on results obtained from in silico analysis, we have chosen genes from neurotrophin signaling pathway for further experiments—BDNF, HRAS, and BCL2. Results obtained in this study suggested that high dose of IL-17 exerts protective activity via miR-155-5p downregulation. Increased expression of all studied genes, especially BCL2, indicated a potential anti-apoptotic function of IL-17 during the preclinical phase of EAE.

Comorbidity Analysis between Alzheimer's Disease and Type 2 Diabetes Mellitus (T2DM) Based on Shared Pathways and the Role of T2DM Drugs.

Background:Various studies suggest a comorbid association between Alzheimer’s disease (AD) and type 2 diabetes mellitus (T2DM) indicating that there could be shared underlying pathophysiological mechanisms.Objective:This study aims to systematically model relevant knowledge at the molecular level to find a mechanistic rationale explaining the existing comorbid association between AD and T2DM.Method:We have used a knowledge-based modeling approach to build two network models for AD and T2DM using Biological Expression Language (BEL), which is capable of capturing and representing causal and correlative relationships at both molecular and clinical levels from various knowledge resources.Results:Using comparative analysis, we have identified several putative “shared pathways”. We demonstrate, at a mechanistic level, how the insulin signaling pathway is related to other significant AD pathways such as the neurotrophin signaling pathway, PI3K/AKT signaling, MTOR signaling, and MAPK signaling and how these pathways do cross-talk with each other both in AD and T2DM. In addition, we present a mechanistic hypothesis that explains both favorable and adverse effects of the anti-diabetic drug metformin in AD.Conclusion:The two computable models introduced here provide a powerful framework to identify plausible mechanistic links shared between AD and T2DM and thereby identify targeted pathways for new therapeutics. Our approach can also be used to provide mechanistic answers to the question of why some T2DM treatments seem to increase the risk of AD.

Manganese-Induced Neurotoxicity and Alterations in Gene Expression in Human Neuroblastoma SH-SY5Y Cells.

Manganese (Mn) is an essential trace element required for many physiological functions including proper biochemical and cellular functioning of the central nervous system (CNS). However, exposure to excess level of Mn through occupational settings or from environmental sources has been associated with neurotoxicity. The cellular and molecular mechanism of Mn-induced neurotoxicity remains unclear. In the current study, we investigated the effects of 30-day exposure to a sub-lethal concentration of Mn (100μM) in human neuroblastoma cells (SH-SY5Y) using transcriptomic approach. Microarray analysis revealed differential expression of 1057 transcripts in Mn-exposed SH-SY5Y cells as compared to control cells. Gene functional annotation cluster analysis exhibited that the differentially expressed genes were associated with several biological pathways. Specifically, genes involved in neuronal pathways including neuron differentiation and development, regulation of neurogenesis, synaptic transmission, and neuronal cell death (apoptosis) were found to be significantly altered. KEGG pathway analysis showed upregulation of p53 signaling pathways and neuroactive ligand-receptor interaction pathways, and downregulation of neurotrophin signaling pathway. On the basis of the gene expression profile, possible molecular mechanisms underlying Mn-induced neuronal toxicity were predicted.

The circular RNA of peripheral blood mononuclear cells: Hsa_circ_0005836 as a new diagnostic biomarker and therapeutic target of active pulmonary tuberculosis

It has been reported that circular RNA (circRNA) is associated with human cancer. However, few studies have been reported in active pulmonary tuberculosis (APTB). The global circRNA expression was detected in the peripheral blood mononuclear cells (PBMCs) of APTB patients (n=5) and health controls (HC) (n=5) by using high-throughput sequencing. According to the systematical bioinformatics analysis, the basic content of circRNAs and their fold changes in the two groups were calculated. We selected 6 significant differentially expressed circRNAs, hsa_circ_0005836, hsa_circ_0009128, hsa_circ_0003519, hsa_circ_0023956, hsa_circ_0078768, and hsa_circ_0088452 and validated the expression in PBMCs from APTB (n=10) and HC (n=10) by real-time quantitative reverse transcription-polymerase chain reactions (qRT-PCRs). Further, the verification of these specific circRNAs (hsa_circ_0005836 and hsa_circ_0009128) between APTB (n=34) and HC (n=30) in PBMCs was also conducted by qRT-PCRs. The RNA-seq data showed the significant differential expression of the 523 circRNAs between the APTB and HC groups (199 circRNAs were significantly up-regulated and 324 circRNAs were down-regulated). Hsa_circ_0005836 and hsa_circ_0009128 expression was significantly down-regulated in the PBMCs of APTB (P<0.05) in the samples of APTB compared to HC in our study. The gene ontology based enrichment analysis of the circRNA-miRNA-mRNAs network showed that cellular catabolic process (P=7.10E-08), regulation of metabolic process (P=2.10E-06), catalytic activity (P=3.67E-08), protein binding (P=1.71E-07), cell part (P=3.46E-06), intracellular part (P=1.71E-07), and intracellular (P=3.67E-08) were recognized in the comparisons between APTB and HC. Based on KEGG analysis, HTLV-I infection, regulation of actin cytoskeleton, neurotrophin signaling pathway and mTOR signaling pathway were relevant during tuberculosis bacillus infection. We found for the first time that hsa_circ_0005836 and hsa_circ_0009128 were significantly down-regulated in the PBMCs of APTB compared with HC. Our findings indicate hsa_circ_0005836 might serve as a novel potential biomarker for TB infection.

Abstract 2724: Brush biopsy miRNA based OSCC detection and diagnosis

Abstract RNA based diagnosis and prognosis of squamous cell carcinoma has been slow to come to the clinic. Improvements in RNA measurement, statistical evaluation, and sample preservation still have not made these methods accurate enough to allow truly independent external validation. We propose that in the case of squamous cell carcinoma of the oral cavity that a chief source of variability is sample dissection which leads to variable amounts of stroma mixed in with tumor epithelium. We have used brush biopsy of suspicious lesions to characterize miRNA expression in OSCC epithelium. We used it to show an 11 miRNA signature for OSCC that can differentiate OSCC in both smokers and never smokers from normal tissue. We will report on efforts to optimize this classifier to distinguish OSCC from benign oral lesions such as lichen planus and leukoplakia that can be mistaken for OSCC. We also provide evidence that body fluid samples show similar changes in RNAs with OSCC that are seen in brush biopsy samples -suggesting much of the RNA is coming from the same source tumor epithelium. Finally, using a variation of mirPath designed to eliminate false positive, we have identified the neurotrophin signaling pathway as disregulated in most OSCC epithelium, and for the first time highlight the miRNAs that may control this pathway in OSCC, miR-486-5p, miR-7-5p, miR-146-5p, miR-101-3p, miR-18b-5p, miR-10b-5p, miR-21-5p, miR-20b-5p, miR-126-3p and miR-31-5p. Citation Format: Guy R. Adami, Joel L. Schwartz, Yalu Zhou, Jessica L. Tang, Michael Markiewicz, Gina D. Jefferson, Joel Epstein, Antonia Kolokythas. Brush biopsy miRNA based OSCC detection and diagnosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2724. doi:10.1158/1538-7445.AM2017-2724

Synergistic activity of everolimus and 5-aza-2'-deoxycytidine in medullary thyroid carcinoma cell lines.

Medullary thyroid cancer (MTC) is a tumor highly resistant to chemo‐ and radiotherapy. Drug resistance can be induced by epigenetic changes such as aberrant DNA methylation. To overcome drug resistance, we explored a promising approach based on the use of 5‐aza‐2′‐deoxycytidine (AZA), a demethylating agent, in combination with the mTOR inhibitor everolimus in MTC cells (MZ‐CRC‐1 and TT). This combined treatment showed a strong synergistic antiproliferative activity through the induction of apoptosis. The effect of everolimus and/or AZA on genome‐wide expression profiling was evaluated by Illumina BeadChip in MZ‐CRC‐1 cells. An innovative bioinformatic pipeline identified four potential molecular pathways implicated in the synergy between AZA and everolimus: PI3K‐Akt signaling, the neurotrophin pathway, ECM/receptor interaction, and focal adhesion. Among these, the neurotrophin signaling pathway was most directly involved in apoptosis, through the overexpression of NGFR and Bax genes. The increased expression of genes involved in the NGFR‐MAPK10‐TP53‐Bax/Bcl2 pathway during incubation with AZA plus everolimus was validated by western blotting in MZ‐CRC‐1 cells. Interestingly, addition of a neutralizing anti‐NGFR antibody inhibited the synergistic cytotoxic activity between AZA and everolimus. These results open a new therapeutic scenario for MTC and potentially other neuroendocrine tumors, where therapy with mTOR inhibitors is currently approved.