JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Insights into Conifer Giga-Genomes.
Plant Physiol.
PUBLISHED: 10-29-2014
Show Abstract
Hide Abstract
Insights from sequenced genomes of major land plant lineages have advanced research in almost every aspect of plant biology. Until recently, however, assembled genome sequences of gymnosperms have been missing from this picture. Conifers of the pine family (Pinaceae) are a group of gymnosperms that dominate large parts of the world's forests. Despite their ecological and economic importance, conifers seemed long out of reach for complete genome sequencing, due in part to their enormous genome size (20-30 Gbp) and highly repetitive nature of their genomes. Technological advances in genome sequencing and assembly enabled the recent publication of three conifer genomes: White spruce (Picea glauca), Norway spruce (P. abies), and loblolly pine (Pinus taeda). These genome sequences revealed distinctive features compared to other plant genomes, and may represent a window into the past of seed plant genomes. This update highlights recent advances, remaining challenges, and opportunities in light of the publication of the first conifer and gymnosperm genomes.
Related JoVE Video
Second-generation antibacterial benzimidazole ureas: discovery of a preclinical candidate with reduced metabolic liability.
J. Med. Chem.
PUBLISHED: 10-28-2014
Show Abstract
Hide Abstract
Compound 3 is a potent aminobenzimidazole urea with broad-spectrum Gram-positive antibacterial activity resulting from dual inhibition of bacterial gyrase (GyrB) and topoisomerase IV (ParE), and it demonstrates efficacy in rodent models of bacterial infection. Preclinical in vitro and in vivo studies showed that compound 3 covalently labels liver proteins, presumably via formation of a reactive metabolite, and hence presented a potential safety liability. The urea moiety in compound 3 was identified as being potentially responsible for reactive metabolite formation, but its replacement resulted in loss of antibacterial activity and/or oral exposure due to poor physicochemical parameters. To identify second-generation aminobenzimidazole ureas devoid of reactive metabolite formation potential, we implemented a metabolic shift strategy, which focused on shifting metabolism away from the urea moiety by introducing metabolic soft spots elsewhere in the molecule. Aminobenzimidazole urea 34, identified through this strategy, exhibits similar antibacterial activity as that of 3 and did not label liver proteins in vivo, indicating reduced/no potential for reactive metabolite formation.
Related JoVE Video
Type IIIb Endoleak Is an Important Cause of Failure Following Endovascular Aneurysm Repair.
J. Endovasc. Ther.
PUBLISHED: 10-08-2014
Show Abstract
Hide Abstract
Purpose : To present confirmed cases of type IIIb endoleak in second and third-generation stent-grafts used for endovascular aneurysm repair (EVAR). Case Reports : Four patients developed type IIIb endoleak caused by fabric tears between 4 and 13 years following their initial EVAR. Three patients presented with rupture and one with aneurysm expansion of unknown cause. In each case, the type IIIb endoleak was confirmed at open surgery after imaging proved non-diagnostic. Only one patient survived. Had the cause for the expansion or ruptures been found prior to open reintervention, relining of the stent-graft may have been possible. Conclusion : Type IIIb endoleak remains difficult to diagnose. Avoidance of the high mortality associated with open secondary intervention requires a high degree of suspicion and it should be considered in any post-EVAR aneurysm expansion without an obvious cause.
Related JoVE Video
Recovery-focused cognitive-behavioural therapy for recent-onset bipolar disorder: randomised controlled pilot trial.
Br J Psychiatry
PUBLISHED: 09-13-2014
Show Abstract
Hide Abstract
Background Despite evidence for the effectiveness of structured psychological therapies for bipolar disorder no psychological interventions have been specifically designed to enhance personal recovery for individuals with recent-onset bipolar disorder. Aims A pilot study to assess the feasibility and effectiveness of a new intervention, recovery-focused cognitive-behavioural therapy(CBT), designed in collaboration with individuals with recent-onset bipolar disorder intended to improve clinical and personal recovery outcomes. Method A single, blind randomised controlled trial compared treatment as usual (TAU) with recovery-focused CBT plus TAU (n = 67). Results Recruitment and follow-up rates within 10% of pre-planned targets to 12-month follow-up were achieved. An average of 14.15 h (s.d. = 4.21) of recovery-focused CBT were attended out of a potential maximum of 18 h. Compared with TAU, recovery-focused CBT significantly improved personal recovery up to 12-month follow-up (Bipolar Recovery Questionnaire mean score 310.87, 95% CI 75.00-546.74 (s.e. = 120.34), P = 0.010, d = 0.62) and increased time to any mood relapse during up to 15 months follow-up (?(2) = 7.64, P<0.006, estimated hazard ratio (HR) = 0.38, 95% CI 0.18-0.78). Groups did not differ with respect to medication adherence. Conclusions Recovery-focused CBT seems promising with respect to feasibility and potential clinical effectiveness. Clinical- and cost-effectiveness now need to be reliably estimated in a definitive trial.
Related JoVE Video
MicroRNA-539 Is Up-regulated in Failing Heart, and Suppresses O-GlcNAcase Expression.
J. Biol. Chem.
PUBLISHED: 09-02-2014
Show Abstract
Hide Abstract
Derangements in metabolism and related signaling pathways characterize the failing heart. One such signal, O-linked ?-N-acetylglucosamine (O-GlcNAc), is an essential post-translational modification regulated by two enzymes, O-GlcNAc transferase and O-GlcNAcase (OGA), which modulate the function of many nuclear and cytoplasmic proteins. We recently reported reduced OGA expression in the failing heart, which is consistent with the pro-adaptive role of increased O-GlcNAcylation during heart failure; however, molecular mechanisms regulating these enzymes during heart failure remain unknown. Using miRNA microarray analysis, we observed acute and chronic changes in expression of several miRNAs. Here, we focused on miR-539 because it was predicted to target OGA mRNA. Indeed, co-transfection of the OGA-3'UTR containing reporter plasmid and miR-539 overexpression plasmid significantly reduced reporter activity. Overexpression of miR-539 in neonatal rat cardiomyocytes significantly suppressed OGA expression and consequently increased O-GlcNAcylation; conversely, the miR-539 inhibitor rescued OGA protein expression and restored O-GlcNAcylation. In conclusion, this work identifies the first target of miR-539 in the heart and the first miRNA that regulates OGA. Manipulation of miR-539 may represent a novel therapeutic target in the treatment of heart failure and other metabolic diseases.
Related JoVE Video
Identification of a Putative Tdp1 Inhibitor (CD00509) by in Vitro and Cell-Based Assays.
J Biomol Screen
PUBLISHED: 08-12-2014
Show Abstract
Hide Abstract
Mutations of DNA repair pathways contribute to tumorigenesis and provide a therapeutic target for synthetic lethal interactions in tumor cells. Given that tyrosyl-DNA phosphodiesterase 1 (Tdp1) repairs stalled topoisomerase-I DNA complexes, we hypothesized that inhibition of Tdp1 has synthetic lethal effects in some cancers. To test this, we screened tumor arrays for Tdp1 expression and observed that Tdp1 is expressed in many tumors, including more than 90% of human breast tumors. Subsequent chemical screening identified putative Tdp1 inhibitors. Treatment of control human mammary epithelial cells and the breast cancer cell line MCF-7 with compound CD00509 preferentially sensitized MCF-7 cells to camptothecin and decreased cell proliferation 25% more than camptothecin treatment alone. This suggests that CD00509 specifically targeted Tdp1 in vitro, and CD00509 increased the sensitivity of wild-type murine embryonic fibroblasts (MEFs) to camptothecin to a degree comparable to that of Tdp1(-/-) MEFs. In addition, consistent with poly ADP-ribose polymerase-1 (PARP-1) collaborating with Tdp1 in DNA repair, combined Tdp1 and PARP-1 inhibition was more detrimental to MCF-7 cells than either treatment alone, whereas the combination was not additively harmful to control mammary cells. We conclude that targeting Tdp1 in anticancer therapy preferentially enhances the sensitivity of some breast cancer cells to camptothecin and may be an effective adjuvant for breast cancer therapy.
Related JoVE Video
A web-based self-management intervention for Bipolar Disorder 'living with bipolar': a feasibility randomised controlled trial.
J Affect Disord
PUBLISHED: 07-27-2014
Show Abstract
Hide Abstract
Bipolar Disorder (BD) is a severe mental health problem. Psychological interventions are recommended by the National Institute for Health and Care Excellence (NICE) but patients experience severe inequalities in access. This study assessed the feasibility and potential effectiveness of a recovery informed web-based self-management intervention for people with BD.
Related JoVE Video
Discovery of a novel, first-in-class, orally bioavailable azaindole inhibitor (VX-787) of influenza PB2.
J. Med. Chem.
PUBLISHED: 07-24-2014
Show Abstract
Hide Abstract
In our effort to develop agents for the treatment of influenza, a phenotypic screening approach utilizing a cell protection assay identified a series of azaindole based inhibitors of the cap-snatching function of the PB2 subunit of the influenza A viral polymerase complex. Using a bDNA viral replication assay (Wagaman, P. C., Leong, M. A., and Simmen, K. A. Development of a novel influenza A antiviral assay. J. Virol. Methods 2002, 105, 105-114) in cells as a direct measure of antiviral activity, we discovered a set of cyclohexyl carboxylic acid analogues, highlighted by VX-787 (2). Compound 2 shows strong potency versus multiple influenza A strains, including pandemic 2009 H1N1 and avian H5N1 flu strains, and shows an efficacy profile in a mouse influenza model even when treatment was administered 48 h after infection. Compound 2 represents a first-in-class, orally bioavailable, novel compound that offers potential for the treatment of both pandemic and seasonal influenza and has a distinct advantage over the current standard of care treatments including potency, efficacy, and extended treatment window.
Related JoVE Video
Disruption of rat testis development following combined in utero exposure to the phytoestrogen genistein and antiandrogenic plasticizer di-(2-ethylhexyl) phthalate.
Biol. Reprod.
PUBLISHED: 07-16-2014
Show Abstract
Hide Abstract
Fetal exposure to environmental endocrine disruptors (EDs) is thought to contribute to reported idiopathic increases in adult male reproductive abnormalities. Although humans are exposed to myriad EDs from conception to adulthood, few studies have evaluated the effects of combined EDs on male reproduction. In the present study, we demonstrate that simultaneous gestational exposure to the phytoestrogen genistein and the antiandrogenic plasticizer di-(2-ethyhexyl) phthalate (DEHP) induces long-term alterations in testis development and function. Pregnant Sprague Dawley rats were gavaged from Gestational Day 14 to birth with corn oil, genistein, DEHP, or their mixture at 10 mg/kg/day, a dose selected from previous dose-response studies using single chemicals for its lack of long-term testicular effects. Hormonal and testicular end points were examined in adult male offspring. Serum testosterone levels were unchanged. However, significant increases were observed in testis weight and in the expression of mast cell markers in testes from adult rats exposed gestationally to combined compounds. The ED mixture also altered the mRNA expression of Sertoli cell makers Wt1 and Amh and germ cell markers cKit and Sox17, measured by quantitative real-time PCR (qPCR), suggesting long-term disruption in testis function and spermatogenesis. Alterations in germ cell markers might reflect direct effects on fetal gonocytes or indirect effects via primary targeting of somatic cells, as suggested by differentially regulated Leydig cell associated genes (Hsd3b, Anxa1, Foxa3, and Pdgfra), determined by gene expression array, qPCR, and protein analyses. The two chemicals, when given in combination, induced long-term reproductive toxicity at doses not previously reported to produce any conspicuous long-term effects. Our study therefore highlights a need for a more comprehensive evaluation of the effects of ED mixtures.
Related JoVE Video
Diagnostic value of next-generation sequencing in an unusual sphenoid tumor.
Oncologist
PUBLISHED: 05-07-2014
Show Abstract
Hide Abstract
Extraordinary advancements in sequencing technology have made what was once a decade-long multi-institutional endeavor into a methodology with the potential for practical use in a clinical setting. We therefore set out to examine the clinical value of next-generation sequencing by enrolling patients with incurable or ambiguous tumors into the Personalized OncoGenomics initiative at the British Columbia Cancer Agency whereby whole genome and transcriptome analyses of tumor/normal tissue pairs are completed with the ultimate goal of directing therapeutics. First, we established that the sequencing, analysis, and communication with oncologists could be completed in less than 5 weeks. Second, we found that cancer diagnostics is an area that can greatly benefit from the comprehensiveness of a whole genome analysis. Here, we present a scenario in which a metastasized sphenoid mass, which was initially thought of as an undifferentiated squamous cell carcinoma, was rediagnosed as an SMARCB1-negative rhabdoid tumor based on the newly acquired finding of homozygous SMARCB1 deletion. The new diagnosis led to a change in chemotherapy and a complete nodal response in the patient. This study also provides additional insight into the mutational landscape of an adult SMARCB1-negative tumor that has not been explored at a whole genome and transcriptome level.
Related JoVE Video
Somatic mosaicism for the p.His1047Arg mutation in PIK3CA in a girl with mesenteric lipomatosis.
Am. J. Med. Genet. A
PUBLISHED: 05-05-2014
Show Abstract
Hide Abstract
We describe a patient who presented with a localized growth of mature fat tissue, which was surgically removed. MRI imaging identified diffuse increase in visceral adipose tissue. Targeted deep sequencing of the resected tissue uncovered a p.H1047R variant in PIK3CA, which was absent in blood. This report expands the phenotypic spectrum of mosaic PIK3CA mutations.
Related JoVE Video
Targeted CNS Delivery Using Human MiniPromoters and Demonstrated Compatibility with Adeno-Associated Viral Vectors.
Mol Ther Methods Clin Dev
PUBLISHED: 04-25-2014
Show Abstract
Hide Abstract
Critical for human gene therapy is the availability of small promoter tools to drive gene expression in a highly specific and reproducible manner. We tackled this challenge by developing human DNA MiniPromoters using computational biology and phylogenetic conservation. MiniPromoters were tested in mouse as single-copy knock-ins at the Hprt locus on the X Chromosome, and evaluated for lacZ reporter expression in CNS and non-CNS tissue. Eighteen novel MiniPromoters driving expression in mouse brain were identified, two MiniPromoters for driving pan-neuronal expression, and 17 MiniPromoters for the mouse eye. Key areas of therapeutic interest were represented in this set: the cerebral cortex, embryonic hypothalamus, spinal cord, bipolar and ganglion cells of the retina, and skeletal muscle. We also demonstrated that three retinal ganglion cell MiniPromoters exhibit similar cell-type specificity when delivered via adeno-associated virus (AAV) vectors intravitreally. We conclude that our methodology and characterization has resulted in desirable expression characteristics that are intrinsic to the MiniPromoter, not dictated by copy number effects or genomic location, and results in constructs predisposed to success in AAV. These MiniPromoters are immediately applicable for pre-clinical studies towards gene therapy in humans, and are publicly available to facilitate basic and clinical research, and human gene therapy.
Related JoVE Video
Metabolomic analysis of pressure-overloaded and infarcted mouse hearts.
Circ Heart Fail
PUBLISHED: 04-24-2014
Show Abstract
Hide Abstract
Cardiac hypertrophy and heart failure are associated with metabolic dysregulation and a state of chronic energy deficiency. Although several disparate changes in individual metabolic pathways have been described, there has been no global assessment of metabolomic changes in hypertrophic and failing hearts in vivo. Hence, we investigated the impact of pressure overload and infarction on myocardial metabolism.
Related JoVE Video
Evolution of gene structure in the conifer Picea glauca: a comparative analysis of the impact of intron size.
BMC Plant Biol.
PUBLISHED: 04-09-2014
Show Abstract
Hide Abstract
A positive relationship between genome size and intron length is observed across eukaryotes including Angiosperms plants, indicating a co-evolution of genome size and gene structure. Conifers have very large genomes and longer introns on average than most plants, but impacts of their large genome and longer introns on gene structure has not be described.
Related JoVE Video
Mutations in SGOL1 cause a novel cohesinopathy affecting heart and gut rhythm.
Nat. Genet.
PUBLISHED: 04-08-2014
Show Abstract
Hide Abstract
The pacemaking activity of specialized tissues in the heart and gut results in lifelong rhythmic contractions. Here we describe a new syndrome characterized by Chronic Atrial and Intestinal Dysrhythmia, termed CAID syndrome, in 16 French Canadians and 1 Swede. We show that a single shared homozygous founder mutation in SGOL1, a component of the cohesin complex, causes CAID syndrome. Cultured dermal fibroblasts from affected individuals showed accelerated cell cycle progression, a higher rate of senescence and enhanced activation of TGF-? signaling. Karyotypes showed the typical railroad appearance of a centromeric cohesion defect. Tissues derived from affected individuals displayed pathological changes in both the enteric nervous system and smooth muscle. Morpholino-induced knockdown of sgol1 in zebrafish recapitulated the abnormalities seen in humans with CAID syndrome. Our findings identify CAID syndrome as a novel generalized dysrhythmia, suggesting a new role for SGOL1 and the cohesin complex in mediating the integrity of human cardiac and gut rhythm.
Related JoVE Video
Analysis of the genome and transcriptome of Cryptococcus neoformans var. grubii reveals complex RNA expression and microevolution leading to virulence attenuation.
PLoS Genet.
PUBLISHED: 04-01-2014
Show Abstract
Hide Abstract
Cryptococcus neoformans is a pathogenic basidiomycetous yeast responsible for more than 600,000 deaths each year. It occurs as two serotypes (A and D) representing two varieties (i.e. grubii and neoformans, respectively). Here, we sequenced the genome and performed an RNA-Seq-based analysis of the C. neoformans var. grubii transcriptome structure. We determined the chromosomal locations, analyzed the sequence/structural features of the centromeres, and identified origins of replication. The genome was annotated based on automated and manual curation. More than 40,000 introns populating more than 99% of the expressed genes were identified. Although most of these introns are located in the coding DNA sequences (CDS), over 2,000 introns in the untranslated regions (UTRs) were also identified. Poly(A)-containing reads were employed to locate the polyadenylation sites of more than 80% of the genes. Examination of the sequences around these sites revealed a new poly(A)-site-associated motif (AUGHAH). In addition, 1,197 miscRNAs were identified. These miscRNAs can be spliced and/or polyadenylated, but do not appear to have obvious coding capacities. Finally, this genome sequence enabled a comparative analysis of strain H99 variants obtained after laboratory passage. The spectrum of mutations identified provides insights into the genetics underlying the micro-evolution of a laboratory strain, and identifies mutations involved in stress responses, mating efficiency, and virulence.
Related JoVE Video
The impact of endovascular aneurysm repair on aortoiliac tortuosity and its use as a predictor of iliac limb complications.
J. Vasc. Surg.
PUBLISHED: 03-25-2014
Show Abstract
Hide Abstract
Aortoiliac tortuosity is often cited subjectively as a causative factor in iliac limb complications after endovascular aneurysm repair (EVAR); however, evidence on this subject is poor. The aim of this study was to investigate the impact of stent grafting on aortoiliac tortuosity and to explore the role of the tortuosity index (TI) as a predictor of iliac limb complications after EVAR.
Related JoVE Video
Creation of the Polish version and adaptation of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Endometrial Cancer Module (QLQ-EN24).
Contemp Oncol (Pozn)
PUBLISHED: 03-20-2014
Show Abstract
Hide Abstract
The purpose of this study was to create and introduce a Polish version of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire for Endometrial Cancer (QLQ-EN24).
Related JoVE Video
The expression level of small non-coding RNAs derived from the first exon of protein-coding genes is predictive of cancer status.
EMBO Rep.
PUBLISHED: 02-17-2014
Show Abstract
Hide Abstract
Small non-coding RNAs (smRNAs) are known to be significantly enriched near the transcriptional start sites of genes. However, the functional relevance of these smRNAs remains unclear, and they have not been associated with human disease. Within the cancer genome atlas project (TCGA), we have generated small RNA datasets for many tumor types. In prior cancer studies, these RNAs have been regarded as transcriptional "noise," due to their apparent chaotic distribution. In contrast, we demonstrate their striking potential to distinguish efficiently between cancer and normal tissues and classify patients with cancer to subgroups of distinct survival outcomes. This potential to predict cancer status is restricted to a subset of these smRNAs, which is encoded within the first exon of genes, highly enriched within CpG islands and negatively correlated with DNA methylation levels. Thus, our data show that genome-wide changes in the expression levels of small non-coding RNAs within first exons are associated with cancer.
Related JoVE Video
Hippo Signaling Influences HNF4A and FOXA2 Enhancer Switching during Hepatocyte Differentiation.
Cell Rep
PUBLISHED: 01-29-2014
Show Abstract
Hide Abstract
Cell fate acquisition is heavily influenced by direct interactions between master regulators and tissue-specific enhancers. However, it remains unclear how lineage-specifying transcription factors, which are often expressed in both progenitor and mature cell populations, influence cell differentiation. Using in vivo mouse liver development as a model, we identified thousands of enhancers that are bound by the master regulators HNF4A and FOXA2 in a differentiation-dependent manner, subject to chromatin remodeling, and associated with differentially expressed target genes. Enhancers exclusively occupied in the embryo were found to be responsive to developmentally regulated TEAD2 and coactivator YAP1. Our data suggest that Hippo signaling may affect hepatocyte differentiation by influencing HNF4A and FOXA2 interactions with temporal enhancers. In summary, transcription factor-enhancer interactions are not only tissue specific but also differentiation dependent, which is an important consideration for researchers studying cancer biology or mammalian development and/or using transformed cell lines.
Related JoVE Video
Quiescent sox2(+) cells drive hierarchical growth and relapse in sonic hedgehog subgroup medulloblastoma.
Cancer Cell
PUBLISHED: 01-28-2014
Show Abstract
Hide Abstract
Functional heterogeneity within tumors presents a significant therapeutic challenge. Here we show that quiescent, therapy-resistant Sox2(+) cells propagate sonic hedgehog subgroup medulloblastoma by a mechanism that mirrors a neurogenic program. Rare Sox2(+) cells produce rapidly cycling doublecortin(+) progenitors that, together with their postmitotic progeny expressing NeuN, comprise tumor bulk. Sox2(+) cells are enriched following anti-mitotic chemotherapy and Smoothened inhibition, creating a reservoir for tumor regrowth. Lineage traces from Sox2(+) cells increase following treatment, suggesting that this population is responsible for relapse. Targeting Sox2(+) cells with the antineoplastic mithramycin abrogated tumor growth. Addressing functional heterogeneity and eliminating Sox2(+) cells presents a promising therapeutic paradigm for treatment of sonic hedgehog subgroup medulloblastoma.
Related JoVE Video
Exome sequencing identifies a novel variant in ACTC1 associated with familial atrial septal defect.
Can J Cardiol
PUBLISHED: 01-28-2014
Show Abstract
Hide Abstract
The genetics of congenital heart disease (CHD) remain incompletely understood. Exome sequencing has been successfully used to identify disease-causing mutations in familial disorders in which candidate gene analyses and linkage mapping have failed.
Related JoVE Video
A Notch-dependent transcriptional hierarchy promotes mesenchymal transdifferentiation in the cardiac cushion.
Dev. Dyn.
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
Valvuloseptal defects are the most common congenital heart defects. Notch signaling-induced endothelial-to-mesenchymal transition (EMT) in the atrioventricular canal (AVC) cushions at murine embryonic day (E)9.5 is a required step during early valve development. Insights to the transcriptional network that is activated in endocardial cells (EC) during EMT and how these pathways direct valve maturation are lacking.
Related JoVE Video
A novel recurrent mutation in ATP1A3 causes CAPOS syndrome.
Orphanet J Rare Dis
PUBLISHED: 01-16-2014
Show Abstract
Hide Abstract
We undertook genetic analysis of three affected families to identify the cause of dominantly-inherited CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy and sensorineural hearing loss) syndrome.
Related JoVE Video
Endothelial dysfunction as a nexus for endothelial cell-cardiomyocyte miscommunication.
Front Physiol
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Most studies of the heart focus on cardiomyocytes (CM) at the exclusion of other cell types such as myocardial endothelial cells (EC). Such mono-cellular approaches propagate the presumption that EC provide a mere "passive lining" or supportive role. In fact, EC contribute to a dynamic network regulating vascular tone, cardiac development, and repair. Two distinct EC types, vascular EC and epicardial EC, possess important structural and signaling properties within both the healthy and diseased myocardium. In this review, we address EC-CM interactions in mature, healthy myocardium, followed by a discussion of diseases characterized by EC dysfunction. Finally, we consider strategies to reverse EC-CM "miscommunication" to improve patients' outcomes in various cardiovascular diseases.
Related JoVE Video
JAGuaR: junction alignments to genome for RNA-seq reads.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
JAGuaR is an alignment protocol for RNA-seq reads that uses an extended reference to increase alignment sensitivity. It uses BWA to align reads to the genome and reference transcript models (including annotated exon-exon junctions) specifically allowing for the possibility of a single read spanning multiple exons. Reads aligned to the transcript models are then re-mapped on to genomic coordinates, transforming alignments that span multiple exons into large-gapped alignments on the genome. While JAGuaR does not detect novel junctions, we demonstrate how JAGuaR generates fast and accurate transcriptome alignments, which allows for both sensitive and specific SNV calling.
Related JoVE Video
Development and validation of a new multidimensional measure of inspiration: associations with risk for bipolar disorder.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Individuals at risk for, and diagnosed with, bipolar disorder (BD) appear to have heightened levels of creativity. Although inspiration is creativity, the ways in which individuals appraise and respond emotionally to inspiration in BD remain unexplored.
Related JoVE Video
Genome Destabilizing Mutator Alleles Drive Specific Mutational Trajectories in Saccharomyces cerevisiae.
Genetics
PUBLISHED: 12-13-2013
Show Abstract
Hide Abstract
In addition to environmental factors and intrinsic variations in base substitution rates, specific genome-destabilizing mutations can shape the mutational trajectory of genomes. How specific alleles influence the nature and position of accumulated mutations in a genomic context is largely unknown. Understanding the impact of genome destabilizing alleles is particularly relevant to cancer genomes where biased mutational signatures are identifiable. We first created a more complete picture of cellular pathways that impact mutation rate using a primary screen to identify essential Saccharomyces cerevisiae gene mutations that cause mutator phenotypes. Drawing primarily on new alleles identified in this resource we measure the impact of diverse mutator alleles on mutation patterns directly by whole-genome sequencing of 68 mutation-accumulation strains derived from wildtype and 11 parental mutator genotypes. The accumulated mutations differ across mutator strains, displaying base-substitution biases, allele-specific mutation hotspots, and break-associated mutation clustering. For example, in mutants of the POL? and the Cdc13-Stn1-Ten1 complex we find a distinct sub-telomeric bias for mutations that we show is independent of the target sequence. Together our data suggest that specific genome instability mutations are sufficient to drive discrete mutational signatures, some of which share properties with mutation patterns seen in tumors. Thus, in a population of cells, genome instability mutations could influence clonal evolution by establishing discrete mutational trajectories for genomes.
Related JoVE Video
Mutational Analysis Reveals the Origin and Therapy-Driven Evolution of Recurrent Glioma.
Science
PUBLISHED: 12-12-2013
Show Abstract
Hide Abstract
Tumor recurrence is a leading cause of cancer mortality. Therapies for recurrent disease may fail, at least in part, because the genomic alterations driving the growth of recurrences are distinct from those in the initial tumor. To explore this hypothesis, we sequenced the exomes of 23 initial low-grade gliomas and recurrent tumors resected from the same patients. In 43% of cases, at least half of the mutations in the initial tumor were undetected at recurrence, including driver mutations in TP53, ATRX, SMARCA4, and BRAF, suggesting recurrent tumors are often seeded by cells derived from the initial tumor at a very early stage of their evolution. Notably, tumors from 6 of 10 patients treated with the chemotherapeutic drug temozolomide (TMZ) followed an alternative evolutionary path to high-grade glioma. At recurrence, these tumors were hypermutated and harbored driver mutations in the RB and AKT-mTOR pathways that bore the signature of TMZ-induced mutagenesis.
Related JoVE Video
A comparison of skeletal maturation in patients with tooth agenesis and unaffected controls assessed by the cervical vertebral maturation (CVM) index.
J Orthod
PUBLISHED: 12-04-2013
Show Abstract
Hide Abstract
Objective: The aims of this study were to (1) investigate if there is a difference in skeletal maturation between tooth agenesis and control patients and (2) whether skeletal maturation is affected by the severity of tooth agenesis. The cervical vertebral maturation (CVM) index can be used to assess skeletal maturation. Design: A retrospective cross-sectional study. Setting: Eastman Dental Hospital, London, UK. Methods and materials: A total of 360 cephalograms of patients aged 9-17 years (164 males and 196 females) allocated to four subgroups (mild, moderate and severe tooth agenesis patients, and controls) were assessed retrospectively. There were 90 patients in each of the four subgroups. The skeletal maturation of each subject was assessed both quantitatively and qualitatively using the CVM index. All patients in the study were either currently receiving treatment or had been discharged from the hospital. Results: There was no statistically significant relationship between skeletal maturation and the presence of tooth agenesis. Furthermore, there was no statistically significant relationship between the skeletal maturity of patients and different severities of tooth agenesis. Conclusions: The data obtained from this group of patients and using this measurement tool alone does not supply sufficient reason to reject the null hypothesis. However, it suggests that it is possible that no difference exists between the groups.
Related JoVE Video
Cardiomyocyte Ogt is essential for postnatal viability.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 11-01-2013
Show Abstract
Hide Abstract
The singly coded gene O-linked-?-N-acetylglucosamine (O-GlcNAc) transferase (Ogt) resides on the X chromosome and is necessary for embryonic stem cell viability during embryogenesis. In mature cells, this enzyme catalyzes the posttranslational modification known as O-GlcNAc to various cellular proteins. Several groups, including our own, have shown that acute increases in protein O-GlcNAcylation are cardioprotective both in vitro and in vivo. Yet, little is known about how OGT affects cardiac function because total body knockout (KO) animals are not viable. Presently, we sought to establish the potential involvement of cardiomyocyte Ogt in cardiac maturation. Initially, we characterized a constitutive cardiomyocyte-specific (cm)OGT KO (c-cmOGT KO) mouse and found that only 12% of the c-cmOGT KO mice survived to weaning age (4 wk old); the surviving animals were smaller than their wild-type littermates, had dilated hearts, and showed overt signs of heart failure. Dysfunctional c-cmOGT KO hearts were more fibrotic, apoptotic, and hypertrophic. Several glycolytic genes were also upregulated; however, there were no gross changes in mitochondrial O2 consumption. Histopathology of the KO hearts indicated the potential involvement of endoplasmic reticulum stress, directing us to evaluate expression of 78-kDa glucose-regulated protein and protein disulfide isomerase, which were elevated. Additional groups of mice were subjected to inducible deletion of cmOGT, which did not produce overt dysfunction within the first couple of weeks of deletion. Yet, long-term loss (via inducible deletion) of cmOGT produced gradual and progressive cardiomyopathy. Thus, cardiomyocyte Ogt is necessary for maturation of the mammalian heart, and inducible deletion of cmOGT in the adult mouse produces progressive ventricular dysfunction.
Related JoVE Video
O-GlcNAc and the cardiovascular system.
Pharmacol. Ther.
PUBLISHED: 10-21-2013
Show Abstract
Hide Abstract
The cardiovascular system is capable of robust changes in response to physiologic and pathologic stimuli through intricate signaling mechanisms. The area of metabolism has witnessed a veritable renaissance in the cardiovascular system. In particular, the post-translational ?-O-linkage of N-acetylglucosamine (O-GlcNAc) to cellular proteins represents one such signaling pathway that has been implicated in the pathophysiology of cardiovascular disease. This highly dynamic protein modification may induce functional changes in proteins and regulate key cellular processes including translation, transcription, and cell death. In addition, its potential interplay with phosphorylation provides an additional layer of complexity to post-translational regulation. The hexosamine biosynthetic pathway generally requires glucose to form the nucleotide sugar, UDP-GlcNAc. Accordingly, O-GlcNAcylation may be altered in response to nutrient availability and cellular stress. Recent literature supports O-GlcNAcylation as an autoprotective response in models of acute stress (hypoxia, ischemia, oxidative stress). Models of sustained stress, such as pressure overload hypertrophy, and infarct-induced heart failure, may also require protein O-GlcNAcylation as a partial compensatory mechanism. Yet, in models of Type II diabetes, O-GlcNAcylation has been implicated in the subsequent development of vascular, and even cardiac, dysfunction. This review will address this apparent paradox and discuss the potential mechanisms of O-GlcNAc-mediated cardioprotection and cardiovascular dysfunction. This discussion will also address potential targets for pharmacologic interventions and the unique considerations related to such targets.
Related JoVE Video
Incremental value and clinical impact of neck sonography for primary hyperparathyroidism: a risk-adjusted analysis.
Can J Surg
PUBLISHED: 09-27-2013
Show Abstract
Hide Abstract
Despite the different preoperative imaging modalities available for parathyroid adenoma localization, there is currently no uniform consensus on the most appropriate preoperative imaging algorithm that should be routinely followed prior to the surgical management of primary hyperparathyroidism (PHPT). We sought to determine the incremental value of adding neck ultrasonography to scintigraphy-based imaging tests.
Related JoVE Video
Non-coding-regulatory regions of human brain genes delineated by bacterial artificial chromosome knock-in mice.
BMC Biol.
PUBLISHED: 07-09-2013
Show Abstract
Hide Abstract
The next big challenge in human genetics is understanding the 98% of the genome that comprises non-coding DNA. Hidden in this DNA are sequences critical for gene regulation, and new experimental strategies are needed to understand the functional role of gene-regulation sequences in health and disease. In this study, we build upon our HuGX (high-throughput human genes on the X chromosome) strategy to expand our understanding of human gene regulation in vivo.
Related JoVE Video
Relation of hepatic steatosis to atherogenic dyslipidemia.
Am. J. Cardiol.
PUBLISHED: 06-15-2013
Show Abstract
Hide Abstract
Hepatic steatosis is closely associated with the metabolic syndrome. We assessed for an independent association between hepatic steatosis and atherogenic dyslipidemia after adjustment for obesity, physical activity, hyperglycemia, and systemic inflammation. We studied 6,333 asymptomatic subjects without clinical cardiovascular disease undergoing a health screen in Brazil from November 2008 to July 2010. Hepatic steatosis was diagnosed by ultrasound. Atherogenic dyslipidemia was defined using 2 definitions: criteria for (1) metabolic syndrome or (2) insulin resistance (triglyceride/high-density-lipoprotein cholesterol ratio of ?2.5 in women and ?3.5 in men). In hierarchical multivariate regression models, we evaluated for an independent association of hepatic steatosis with atherogenic dyslipidemia. Hepatic steatosis was detected in 36% of participants (average age 43.5 years, 79% men, average body mass index 26.3 kg/m(2)). Subjects with hepatic steatosis had similar levels of low-density-lipoprotein cholesterol, with significantly lower level of high-density-lipoprotein cholesterol and higher level of triglyceride compared with those without steatosis. Hepatic steatosis remained significantly independently associated with atherogenic dyslipidemia of both definitions (metabolic syndrome [odds ratio 2.47, 95% confidence interval 2.03 to 3.02] and insulin resistance [odds ratio 2.50, 95% confidence interval 2.13 to 2.91]) after multivariate adjustment. Stratified analyses showed a persistent independent association in nonobese subjects, those without metabolic syndrome, those with normal high-sensitivity C-reactive protein, nonalcohol abusers, and those with normal liver enzymes. Hepatic steatosis was significantly associated with atherogenic dyslipidemia independent of obesity, physical activity, hyperglycemia, and systemic inflammation after multivariate adjustment. In conclusion, this adds to the growing body of evidence that hepatic steatosis may play a direct metabolic role in conferring increased cardiovascular risk.
Related JoVE Video
Mutational and structural analysis of diffuse large B-cell lymphoma using whole-genome sequencing.
Blood
PUBLISHED: 05-22-2013
Show Abstract
Hide Abstract
Diffuse large B-cell lymphoma (DLBCL) is a genetically heterogeneous cancer composed of at least 2 molecular subtypes that differ in gene expression and distribution of mutations. Recently, application of genome/exome sequencing and RNA-seq to DLBCL has revealed numerous genes that are recurrent targets of somatic point mutation in this disease. Here we provide a whole-genome-sequencing-based perspective of DLBCL mutational complexity by characterizing 40 de novo DLBCL cases and 13 DLBCL cell lines and combining these data with DNA copy number analysis and RNA-seq from an extended cohort of 96 cases. Our analysis identified widespread genomic rearrangements including evidence for chromothripsis as well as the presence of known and novel fusion transcripts. We uncovered new gene targets of recurrent somatic point mutations and genes that are targeted by focal somatic deletions in this disease. We highlight the recurrence of germinal center B-cell-restricted mutations affecting genes that encode the S1P receptor and 2 small GTPases (GNA13 and GNAI2) that together converge on regulation of B-cell homing. We further analyzed our data to approximate the relative temporal order in which some recurrent mutations were acquired and demonstrate that ongoing acquisition of mutations and intratumoral clonal heterogeneity are common features of DLBCL. This study further improves our understanding of the processes and pathways involved in lymphomagenesis, and some of the pathways mutated here may indicate new avenues for therapeutic intervention.
Related JoVE Video
Assembling the 20 Gb white spruce (Picea glauca) genome from whole-genome shotgun sequencing data.
Bioinformatics
PUBLISHED: 05-22-2013
Show Abstract
Hide Abstract
White spruce (Picea glauca) is a dominant conifer of the boreal forests of North America, and providing genomics resources for this commercially valuable tree will help improve forest management and conservation efforts. Sequencing and assembling the large and highly repetitive spruce genome though pushes the boundaries of the current technology. Here, we describe a whole-genome shotgun sequencing strategy using two Illumina sequencing platforms and an assembly approach using the ABySS software. We report a 20.8 giga base pairs draft genome in 4.9 million scaffolds, with a scaffold N50 of 20,356 bp. We demonstrate how recent improvements in the sequencing technology, especially increasing read lengths and paired end reads from longer fragments have a major impact on the assembly contiguity. We also note that scalable bioinformatics tools are instrumental in providing rapid draft assemblies.
Related JoVE Video
Identifying cancer mutation targets across thousands of samples: MuteProc, a high throughput mutation analysis pipeline.
BMC Bioinformatics
PUBLISHED: 05-17-2013
Show Abstract
Hide Abstract
In the past decade, bioinformatics tools have matured enough to reliably perform sophisticated primary data analysis on Next Generation Sequencing (NGS) data, such as mapping, assemblies and variant calling, however, there is still a dire need for improvements in the higher level analysis such as NGS data organization, analysis of mutation patterns and Genome Wide Association Studies (GWAS).
Related JoVE Video
Distinct roles of KAP1, HP1 and G9a/GLP in silencing of the two-cell-specific retrotransposon MERVL in mouse ES cells.
Epigenetics Chromatin
PUBLISHED: 05-08-2013
Show Abstract
Hide Abstract
In mouse embryonic stem cells (mESCs), transcriptional silencing of numerous class I and II endogenous retroviruses (ERVs), including IAP, ETn and MMERVK10C, is dependent upon the H3K9 methyltransferase (KMTase) SETDB1/ESET and its binding partner KAP1/TRIM28. In contrast, the H3K9 KMTases G9a and GLP and HP1 proteins are dispensable for this process. Intriguingly, MERVL retroelements are actively transcribed exclusively in the two-cell (2C) embryo, but the molecular basis of silencing of these class III ERVs at later developmental stages has not been systematically addressed.
Related JoVE Video
Genome-wide microRNA and messenger RNA profiling in rodent liver development implicates mir302b and mir20a in repressing transforming growth factor-beta signaling.
Hepatology
PUBLISHED: 04-26-2013
Show Abstract
Hide Abstract
MicroRNAs (miRNAs) are recently discovered small RNA molecules that regulate developmental processes, such as proliferation, differentiation, and apoptosis; however, the identity of miRNAs and their functions during liver development are largely unknown. Here we investigated the miRNA and gene expression profiles for embryonic day (E)8.5 endoderm, E14.5 Dlk1(+) liver cells (hepatoblasts), and adult liver by employing Illumina sequencing. We found that miRNAs were abundantly expressed at all three stages. Using K-means clustering analysis, 13 miRNA clusters with distinct temporal expression patterns were identified. mir302b, an endoderm-enriched miRNA, was identified as an miRNA whose predicted targets are expressed highly in E14.5 hepatoblasts but low in the endoderm. We validated the expression of mir302b in the endoderm by whole-mount in situ hybridization. Interestingly, mir20a, the most highly expressed miRNA in the endoderm library, was also predicted to regulate some of the same targets as mir302b. We found that through targeting Tgfbr2, mir302b and mir20a are able to regulate transforming growth factor beta (TGF?) signal transduction. Moreover, mir302b can repress liver markers in an embryonic stem cell differentiation model. Collectively, we uncovered dynamic patterns of individual miRNAs during liver development, as well as miRNA networks that could be essential for the specification and differentiation of liver progenitors. (HEPATOLOGY 2013).
Related JoVE Video
Luteolin is a novel p90 ribosomal S6 kinase (RSK) inhibitor that suppresses Notch4 signaling by blocking the activation of Y-box binding protein-1 (YB-1).
Oncotarget
PUBLISHED: 04-18-2013
Show Abstract
Hide Abstract
Triple-negative breast cancers (TNBC) are notoriously difficult to treat because they lack hormone receptors and have limited targeted therapies. Recently, we demonstrated that p90 ribosomal S6 kinase (RSK) is essential for TNBC growth and survival indicating it as a target for therapeutic development. RSK phosphorylates Y-box binding protein-1 (YB-1), an oncogenic transcription/translation factor, highly expressed in TNBC (~70% of cases) and associated with poor prognosis, drug resistance and tumor initiation. YB-1 regulates the tumor-initiating cell markers, CD44 and CD49f however its role in Notch signaling has not been explored. We sought to identify novel chemical entities with RSK inhibitory activity. The Prestwick Chemical Library of 1120 off-patent drugs was screened for RSK inhibitors using both in vitro kinase assays and molecular docking. The lead candidate, luteolin, inhibited RSK1 and RSK2 kinase activity and suppressed growth in TNBC, including TIC-enriched populations. Combining luteolin with paclitaxel increased cell death and unlike chemotherapy alone, did not enrich for CD44(+) cells. Luteolins efficacy against drug-resistant cells was further indicated in the primary x43 cell line, where it suppressed monolayer growth and mammosphere formation. We next endeavored to understand how the inhibition of RSK/YB-1 signaling by luteolin elicited an effect on TIC-enriched populations. ChIP-on-ChIP experiments in SUM149 cells revealed a 12-fold enrichment of YB-1 binding to the Notch4 promoter. We chose to pursue this because there are several reports indicating that Notch4 maintains cells in an undifferentiated, TIC state. Herein we report that silencing YB-1 with siRNA decreased Notch4 mRNA. Conversely, transient expression of Flag:YB-1(WT) or the constitutively active mutant Flag:YB-1(D102) increased Notch4 mRNA. The levels of Notch4 transcript and the abundance of the Notch4 intracellular domain (N4ICD) correlated with activation of P-RSK(S221/7) and P-YB-1(S102) in a panel of TNBC cell lines. Silencing YB-1 or RSK reduced Notch4 mRNA and this corresponded with loss of N4ICD. Likewise, the RSK inhibitors, luteolin and BI-D1870, suppressed P-YB-1(S102) and thereby reduced Notch4. In conclusion, inhibiting the RSK/YB-1 pathway with luteolin is a novel approach to blocking Notch4 signaling and as such provides a means of inhibiting TICs.
Related JoVE Video
A Pilot Web Based Positive Parenting Intervention to Help Bipolar Parents to Improve Perceived Parenting Skills and Child Outcomes.
Behav Cogn Psychother
PUBLISHED: 04-02-2013
Show Abstract
Hide Abstract
Background: Children of bipolar parents are at elevated risk for psychiatric disorders including bipolar disorder. Helping bipolar parents to optimize parenting skills may improve their childrens mental health outcomes. Clear evidence exists for benefits of behavioural parenting programmes, including those for depressed mothers. However, no studies have explored web-based self-directed parenting interventions for bipolar parents. Aims: The aim of this research was to conduct a pilot study of a web-based parenting intervention based on the Triple P-Positive Parenting Programme. Method: Thirty-nine self-diagnosed bipolar parents were randomly allocated to the web-based intervention or a waiting list control condition. Parents reported on their index child (entry criterion age 4-10 years old). Perceived parenting behaviour and child behaviour problems (internalizing and externalizing) were assessed at inception and 10 weeks later (at course completion). Fifteen participants (4 control group and 11 intervention group) did not provide follow-up data. Results: Levels of child behaviour problems (parent rated; Strengths and Difficulties Questionnaire) were above clinical thresholds at baseline, and problematic perceived parenting (self-rated; Parenting Scale) was at similar levels to those in previous studies of children with clinically significant emotional and behavioural problems. Parents in the intervention group reported improvements in child behaviour problems and problematic perceived parenting compared to controls. Conclusions: A web-based positive parenting intervention may have benefits for bipolar parents and their children. Initial results support improvement in child behaviour and perceived parenting. A more definitive study addressing the limitations of the current work is now called for.
Related JoVE Video
Assessing the specificity of autobiographical memory in individuals at a trait-based vulnerability to bipolar disorder using a sentence completion task.
Memory
PUBLISHED: 03-28-2013
Show Abstract
Hide Abstract
Overgeneral autobiographical memory recall has been associated with the diagnosis of bipolar disorder, but the role of overgenerality in the vulnerability to bipolar disorder remains under-researched. While a previous study suggested that high-risk individuals for bipolar disorder recall emotionally negative memories in specific detail, this is in contrast to memory recall patterns noted in bipolar samples. The Autobiographical Memory Test (AMT) used in previous non-clinical studies has also been criticised for not being sensitive to overgenerality due to its repetition of specificity instructions and practice trials. The traditional AMT format may allow some individuals to override their trait-based tendencies to be overgeneral. The current study used a sentence completion task to assess memory specificity in groups of students at a low and high trait-based vulnerability for bipolar disorder. In contrast to previous research, high-risk individuals recalled fewer specific positive memories and greater numbers of overgeneral negative memories than low-risk individuals. These results support the notion that the vulnerability for bipolar disorder might be associated with similar recall biases as demonstrated in bipolar samples, and that the AMT might not be sufficiently sensitive to detect overgenerality in non-clinical groups. The implications of these findings and directions for future research are discussed.
Related JoVE Video
Draft genome of the mountain pine beetle, Dendroctonus ponderosae Hopkins, a major forest pest.
Genome Biol.
PUBLISHED: 03-27-2013
Show Abstract
Hide Abstract
BACKGROUND: The mountain pine beetle, Dendroctonus ponderosae Hopkins, is the most serious insect pest of western North American pine forests. A recent outbreak destroyed more than 15 million hectares of pine forests, with major environmental effects on forest health, and economic effects on the forest industry. The outbreak has in part been driven by climate change, and will contribute to increased carbon emissions through decaying forests. RESULTS: We developed a genome sequence resource for the mountain pine beetle to better understand the unique aspects of this insects biology. A draft de novo genome sequence was assembled from paired-end, short-read sequences from an individual field-collected male pupa, and scaffolded using mate-paired, short-read genomic sequences from pooled field-collected pupae, paired-end short-insert whole-transcriptome shotgun sequencing reads of mRNA from adult beetle tissues, and paired-end Sanger EST sequences from various life stages. We describe the cytochrome P450, glutathione S-transferase, and plant cell wall-degrading enzyme gene families important to the survival of the mountain pine beetle in its harsh and nutrient-poor host environment, and examine genome-wide single-nucleotide polymorphism variation. A horizontally transferred bacterial sucrose-6-phosphate hydrolase was evident in the genome, and its tissue-specific transcription suggests a functional role for this beetle. CONCLUSIONS: Despite Coleoptera being the largest insect order with over 400,000 described species, including many agricultural and forest pest species, this is only the second genome sequence reported in Coleoptera, and will provide an important resource for the Curculionoidea and other insects.
Related JoVE Video
Transcriptome resources and functional characterization of monoterpene synthases for two host species of the mountain pine beetle, lodgepole pine (Pinus contorta) and jack pine (Pinus banksiana).
BMC Plant Biol.
PUBLISHED: 03-15-2013
Show Abstract
Hide Abstract
The mountain pine beetle (MPB, Dendroctonus ponderosae) epidemic has affected lodgepole pine (Pinus contorta) across an area of more than 18 million hectares of pine forests in western Canada, and is a threat to the boreal jack pine (Pinus banksiana) forest. Defence of pines against MPB and associated fungal pathogens, as well as other pests, involves oleoresin monoterpenes, which are biosynthesized by families of terpene synthases (TPSs). Volatile monoterpenes also serve as host recognition cues for MPB and as precursors for MPB pheromones. The genes responsible for terpene biosynthesis in jack pine and lodgepole pine were previously unknown.
Related JoVE Video
Complete genomic landscape of a recurring sporadic parathyroid carcinoma.
J. Pathol.
PUBLISHED: 03-15-2013
Show Abstract
Hide Abstract
Parathyroid carcinoma is a rare endocrine malignancy with an estimated incidence of less than 1 per million population. Excessive secretion of parathyroid hormone, extremely high serum calcium level, and the deleterious effects of hypercalcaemia are the clinical manifestations of the disease. Up to 60% of patients develop multiple disease recurrences and although long-term survival is possible with palliative surgery, permanent remission is rarely achieved. Molecular drivers of sporadic parathyroid carcinoma have remained largely unknown. Previous studies, mostly based on familial cases of the disease, suggested potential roles for the tumour suppressor MEN1 and proto-oncogene RET in benign parathyroid tumourigenesis, while the tumour suppressor HRPT2 and proto-oncogene CCND1 may also act as drivers in parathyroid cancer. Here, we report the complete genomic analysis of a sporadic and recurring parathyroid carcinoma. Mutational landscapes of the primary and recurrent tumour specimens were analysed using high-throughput sequencing technologies. Such molecular profiling allowed for identification of somatic mutations never previously identified in this malignancy. These included single nucleotide point mutations in well-characterized cancer genes such as mTOR, MLL2, CDKN2C, and PIK3CA. Comparison of acquired mutations in patient-matched primary and recurrent tumours revealed loss of PIK3CA activating mutation during the evolution of the tumour from the primary to the recurrence. Structural variations leading to gene fusions and regions of copy loss and gain were identified at a single-base resolution. Loss of the short arm of chromosome 1, along with somatic missense and truncating mutations in CDKN2C and THRAP3, respectively, provides new evidence for the potential role of these genes as tumour suppressors in parathyroid cancer. The key somatic mutations identified in this study can serve as novel diagnostic markers as well as therapeutic targets.
Related JoVE Video
Analysis of FOXO1 mutations in diffuse large B-cell lymphoma.
Blood
PUBLISHED: 03-04-2013
Show Abstract
Hide Abstract
Diffuse large B-cell lymphoma (DLBCL) accounts for 30% to 40% of newly diagnosed lymphomas and has an overall cure rate of approximately 60%. Previously, we observed FOXO1 mutations in non-Hodgkin lymphoma patient samples. To explore the effects of FOXO1 mutations, we assessed FOXO1 status in 279 DLBCL patient samples and 22 DLBCL-derived cell lines. FOXO1 mutations were found in 8.6% (24/279) of DLBCL cases: 92.3% (24/26) of mutations were in the first exon, 46.2% (12/26) were recurrent mutations affecting the N-terminal region, and another 38.5% (10/26) affected the Forkhead DNA binding domain. Recurrent mutations in the N-terminal region resulted in diminished T24 phosphorylation, loss of interaction with 14-3-3, and nuclear retention. FOXO1 mutation was associated with decreased overall survival in patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (P = .037), independent of cell of origin (COO) and the revised International Prognostic Index (R-IPI). This association was particularly evident (P = .003) in patients in the low-risk R-IPI categories. The independent relationship of mutations in FOXO1 to survival, transcending the prognostic influence of the R-IPI and COO, indicates that FOXO1 mutation is a novel prognostic factor that plays an important role in DLBCL pathogenesis.
Related JoVE Video
akirin is required for diakinesis bivalent structure and synaptonemal complex disassembly at meiotic prophase I.
Mol. Biol. Cell
PUBLISHED: 01-30-2013
Show Abstract
Hide Abstract
During meiosis, evolutionarily conserved mechanisms regulate chromosome remodeling, leading to the formation of a tight bivalent structure. This bivalent, a linked pair of homologous chromosomes, is essential for proper chromosome segregation in meiosis. The formation of a tight bivalent involves chromosome condensation and restructuring around the crossover. The synaptonemal complex (SC), which mediates homologous chromosome association before crossover formation, disassembles concurrently with increased condensation during bivalent remodeling. Both chromosome condensation and SC disassembly are likely critical steps in acquiring functional bivalent structure. The mechanisms controlling SC disassembly, however, remain unclear. Here we identify akir-1 as a gene involved in key events of meiotic prophase I in Caenorhabditis elegans. AKIR-1 is a protein conserved among metazoans that lacks any previously known function in meiosis. We show that akir-1 mutants exhibit severe meiotic defects in late prophase I, including improper disassembly of the SC and aberrant chromosome condensation, independently of the condensin complexes. These late-prophase defects then lead to aberrant reconfiguring of the bivalent. The meiotic divisions are delayed in akir-1 mutants and are accompanied by lagging chromosomes. Our analysis therefore provides evidence for an important role of proper SC disassembly in configuring a functional bivalent structure.
Related JoVE Video
The genetic landscape of high-risk neuroblastoma.
Nat. Genet.
PUBLISHED: 01-20-2013
Show Abstract
Hide Abstract
Neuroblastoma is a malignancy of the developing sympathetic nervous system that often presents with widespread metastatic disease, resulting in survival rates of less than 50%. To determine the spectrum of somatic mutation in high-risk neuroblastoma, we studied 240 affected individuals (cases) using a combination of whole-exome, genome and transcriptome sequencing as part of the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) initiative. Here we report a low median exonic mutation frequency of 0.60 per Mb (0.48 nonsilent) and notably few recurrently mutated genes in these tumors. Genes with significant somatic mutation frequencies included ALK (9.2% of cases), PTPN11 (2.9%), ATRX (2.5%, and an additional 7.1% had focal deletions), MYCN (1.7%, causing a recurrent p.Pro44Leu alteration) and NRAS (0.83%). Rare, potentially pathogenic germline variants were significantly enriched in ALK, CHEK2, PINK1 and BARD1. The relative paucity of recurrent somatic mutations in neuroblastoma challenges current therapeutic strategies that rely on frequently altered oncogenic drivers.
Related JoVE Video
A randomised controlled trial of time limited CBT informed psychological therapy for anxiety in bipolar disorder.
BMC Psychiatry
PUBLISHED: 01-09-2013
Show Abstract
Hide Abstract
Anxiety comorbidity is common in bipolar disorder and is associated with worse treatment outcomes, greater risk of self harm, suicide and substance misuse. To date however there have been no psychological interventions specifically designed to address this problem. The primary objective of this trial is to establish the acceptability and feasibility of a new integrated intervention for anxiety in bipolar disorder designed in collaboration with individuals with personal experience of both problems.
Related JoVE Video
MotifOrganizer: a scalable model-based motif clustering tool for mammalian genomes.
Front Biosci (Elite Ed)
PUBLISHED: 01-02-2013
Show Abstract
Hide Abstract
Assembling a comprehensive catalog of all transcription factors (TFs) and the genes that they regulate (regulon) is important for understanding gene regulation. The sequence-specific conserved binding profiles of TFs can be characterized from whole genome sequences with phylogenetic approaches, and a large number of such profiles have been released. Effective mining of these data sources could reveal novel functional elements computationally. Due to the variability of the binding sites, it is necessary to generalize profiles pertinent to the same TF by clustering. The summarized familial profile is effective in identifying unknown binding sites, thus lead to gene co-regulation prediction. Here we report MotifOrganizer, a scalable model-based clustering algorithm designed for grouping motifs identified from large scale comparative genomics studies on mammalian species. The new algorithm allows grouping of motifs with variable widths and a novel two-stage operation scheme further increases the scalability. MotifOrgainzer demonstrated favorable performance comparing to distance-based and single-stage model-based clustering tools on simulated data. Tests on approximately 150k motifs from the cisRED human database demonstrated that MotifOrganizer can effectively cluster whole genome sets of mammalian motifs.
Related JoVE Video
High fat feeding in mice is insufficient to induce cardiac dysfunction and does not exacerbate heart failure.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Preclinical studies of animals with risk factors, and how those risk factors contribute to the development of cardiovascular disease and cardiac dysfunction, are clearly needed. One such approach is to feed mice a diet rich in fat (i.e. 60%). Here, we determined whether a high fat diet was sufficient to induce cardiac dysfunction in mice. We subjected mice to two different high fat diets (lard or milk as fat source) and followed them for over six months and found no significant decrement in cardiac function (via echocardiography), despite robust adiposity and impaired glucose disposal. We next determined whether antecedent and concomitant exposure to high fat diet (lard) altered the murine hearts response to infarct-induced heart failure; high fat feeding during, or before and during, heart failure did not significantly exacerbate cardiac dysfunction. Given the lack of a robust effect on cardiac dysfunction with high fat feeding, we then examined a commonly used mouse model of overt diabetes, hyperglycemia, and obesity (db/db mice). db/db mice (or STZ treated wild-type mice) subjected to pressure overload exhibited no significant exacerbation of cardiac dysfunction; however, ischemia-reperfusion injury significantly depressed cardiac function in db/db mice compared to their non-diabetic littermates. Thus, we were able to document a negative influence of a risk factor in a relevant cardiovascular disease model; however, this did not involve exposure to a high fat diet. High fat diet, obesity, or hyperglycemia does not necessarily induce cardiac dysfunction in mice. Although many investigators use such diabetes/obesity models to understand cardiac defects related to risk factors, this study, along with those from several other groups, serves as a cautionary note regarding the use of murine models of diabetes and obesity in the context of heart failure.
Related JoVE Video
Whole genome duplication and enrichment of metal cation transporters revealed by de novo genome sequencing of extremely halotolerant black yeast Hortaea werneckii.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Hortaea werneckii, ascomycetous yeast from the order Capnodiales, shows an exceptional adaptability to osmotically stressful conditions. To investigate this unusual phenotype we obtained a draft genomic sequence of a H. werneckii strain isolated from hypersaline water of solar saltern. Two of its most striking characteristics that may be associated with a halotolerant lifestyle are the large genetic redundancy and the expansion of genes encoding metal cation transporters. Although no sexual state of H. werneckii has yet been described, a mating locus with characteristics of heterothallic fungi was found. The total assembly size of the genome is 51.6 Mb, larger than most phylogenetically related fungi, coding for almost twice the usual number of predicted genes (23333). The genome appears to have experienced a relatively recent whole genome duplication, and contains two highly identical gene copies of almost every protein. This is consistent with some previous studies that reported increases in genomic DNA content triggered by exposure to salt stress. In hypersaline conditions transmembrane ion transport is of utmost importance. The analysis of predicted metal cation transporters showed that most types of transporters experienced several gene duplications at various points during their evolution. Consequently they are present in much higher numbers than expected. The resulting diversity of transporters presents interesting biotechnological opportunities for improvement of halotolerance of salt-sensitive species. The involvement of plasma P-type H? ATPases in adaptation to different concentrations of salt was indicated by their salt dependent transcription. This was not the case with vacuolar H? ATPases, which were transcribed constitutively. The availability of this genomic sequence is expected to promote the research of H. werneckii. Studying its extreme halotolerance will not only contribute to our understanding of life in hypersaline environments, but should also identify targets for improving the salt- and osmotolerance of economically important plants and microorganisms.
Related JoVE Video
Recurrent somatic DICER1 mutations in nonepithelial ovarian cancers.
N. Engl. J. Med.
PUBLISHED: 12-21-2011
Show Abstract
Hide Abstract
Germline truncating mutations in DICER1, an endoribonuclease in the RNase III family that is essential for processing microRNAs, have been observed in families with the pleuropulmonary blastoma-family tumor and dysplasia syndrome. Mutation carriers are at risk for nonepithelial ovarian tumors, notably sex cord-stromal tumors.
Related JoVE Video
Hive plots--rational approach to visualizing networks.
Brief. Bioinformatics
PUBLISHED: 12-09-2011
Show Abstract
Hide Abstract
Networks are typically visualized with force-based or spectral layouts. These algorithms lack reproducibility and perceptual uniformity because they do not use a node coordinate system. The layouts can be difficult to interpret and are unsuitable for assessing differences in networks. To address these issues, we introduce hive plots (http://www.hiveplot.com) for generating informative, quantitative and comparable network layouts. Hive plots depict network structure transparently, are simple to understand and can be easily tuned to identify patterns of interest. The method is computationally straightforward, scales well and is amenable to a plugin for existing tools.
Related JoVE Video
"Recovery" in bipolar disorder: how can service users be supported through a self-management intervention? A qualitative focus group study.
J Ment Health
PUBLISHED: 12-05-2011
Show Abstract
Hide Abstract
Bipolar disorder (BD) is a chronic and recurrent affective disorder. Recovery is defined as the process by which people can live fulfilling lives despite experiencing symptoms.
Related JoVE Video
Self-management in bipolar disorder: the story so far.
J Ment Health
PUBLISHED: 12-01-2011
Show Abstract
Hide Abstract
Research suggests that psychoeducation, relapse prevention and recovery are all the key aspects of psychological treatment for bipolar disorder and the common components of self-management programmes.
Related JoVE Video
Identification and characterization of Hoxa9 binding sites in hematopoietic cells.
Blood
PUBLISHED: 11-09-2011
Show Abstract
Hide Abstract
The clustered homeobox proteins play crucial roles in development, hematopoiesis, and leukemia, yet the targets they regulate and their mechanisms of action are poorly understood. Here, we identified the binding sites for Hoxa9 and the Hox cofactor Meis1 on a genome-wide level and profiled their associated epigenetic modifications and transcriptional targets. Hoxa9 and the Hox cofactor Meis1 cobind at hundreds of highly evolutionarily conserved sites, most of which are distant from transcription start sites. These sites show high levels of histone H3K4 monomethylation and CBP/P300 binding characteristic of enhancers. Furthermore, a subset of these sites shows enhancer activity in transient transfection assays. Many Hoxa9 and Meis1 binding sites are also bound by PU.1 and other lineage-restricted transcription factors previously implicated in establishment of myeloid enhancers. Conditional Hoxa9 activation is associated with CBP/P300 recruitment, histone acetylation, and transcriptional activation of a network of proto-oncogenes, including Erg, Flt3, Lmo2, Myb, and Sox4. Collectively, this work suggests that Hoxa9 regulates transcription by interacting with enhancers of genes important for hematopoiesis and leukemia.
Related JoVE Video
Mutations in EZH2 cause Weaver syndrome.
Am. J. Hum. Genet.
PUBLISHED: 10-27-2011
Show Abstract
Hide Abstract
We used trio-based whole-exome sequencing to analyze two families affected by Weaver syndrome, including one of the original families reported in 1974. Filtering of rare variants in the affected probands against the parental variants identified two different de novo mutations in the enhancer of zeste homolog 2 (EZH2). Sanger sequencing of EZH2 in a third classically-affected proband identified a third de novo mutation in this gene. These data show that mutations in EZH2 cause Weaver syndrome.
Related JoVE Video
The effects of lubrication on the static frictional resistance of orthodontic brackets.
Aust Orthod J
PUBLISHED: 10-25-2011
Show Abstract
Hide Abstract
Difficulties are experienced with the collection and storage of freshly harvested human saliva to use as a lubricant for the laboratory testing of the frictional resistance of orthodontic brackets. In order to overcome these difficulties, researchers have suggested the use of saliva substitutes due to their ease of storage and consistency of properties throughout testing. Others have criticized the use of artificial saliva and prefer the dry state. The present study aimed to compare the effects of human saliva and an artificial saliva (Saliva Orthana) with the dry state for the static frictional resistance testing of orthodontic brackets.
Related JoVE Video
Single immunization with a monovalent vesicular stomatitis virus-based vaccine protects nonhuman primates against heterologous challenge with Bundibugyo ebolavirus.
J. Infect. Dis.
PUBLISHED: 10-12-2011
Show Abstract
Hide Abstract
The recombinant vesicular stomatitis virus (rVSV) vector-based monovalent vaccine platform expressing a filovirus glycoprotein has been demonstrated to provide protection from lethal challenge with Ebola (EBOV) and Marburg (MARV) viruses both prophylactically and after exposure. This platform provides protection between heterologous strains within a species; however, protection from lethal challenge between species has been largely unsuccessful. To determine whether the rVSV-EBOV vaccines have the potential to provide protection against a newly emerging, phylogenetically related species, cynomolgus macaques were vaccinated with an rVSV vaccine expressing either the glycoprotein of Zaire ebolavirus (ZEBOV) or Côte dIvoire ebolavirus (CIEBOV) and then challenged with Bundibugyo ebolavirus (BEBOV), which was recently proposed as a new EBOV species following an outbreak in Uganda in 2007. A single vaccination with the ZEBOV-specific vaccine provided cross-protection (75% survival) against subsequent BEBOV challenge, whereas vaccination with the CIEBOV-specific vaccine resulted in an outcome similar to mock-immunized animals (33% and 25% survival, respectively). This demonstrates that monovalent rVSV-based vaccines may be useful against a newly emerging species; however, heterologous protection across species remains challenging and may depend on enhancing the immune responses either through booster immunizations or through the inclusion of multiple immunogens.
Related JoVE Video
The relationship between base dimensions, force to failure, and shear bond strengths of bondable molar tubes.
Angle Orthod
PUBLISHED: 10-06-2011
Show Abstract
Hide Abstract
To compare forces versus failure and shear bond strengths, and to explore their association with the base dimensions of four currently available bondable molar tubes.
Related JoVE Video
Integrated motivational interviewing and cognitive-behavioural therapy for bipolar disorder with comorbid substance use.
Clin Psychol Psychother
PUBLISHED: 09-06-2011
Show Abstract
Hide Abstract
Although comorbid substance use is a common problem in bipolar disorder, there has been little research into options for psychological therapy. Studies to date have concentrated on purely cognitive-behavioural approaches, which are not equipped to deal with the ambivalence to change exhibited by many towards therapy designed to change substance use. This paper provides the first report of an integrated psychological treatment approach for bipolar disorder with comorbid substance use. The intervention reported combines motivational interviewing and cognitive-behavioural therapy to address ambivalence and equips individuals with strategies to address substance use. Across five individual case studies, preliminary evidence is reported to support the acceptability and the feasibility of this approach. Despite most participants not highlighting their substance use as a primary therapy target, all but one exhibited reduced use of drugs or alcohol at the end of therapy, sustained at 6 months follow-up. There was some evidence for improvements in mood symptoms and impulsiveness, but this was less clear-cut. The impact of social and relationship issues on therapy process and outcome is discussed. The implications of the current findings for future intervention research in this area are considered.
Related JoVE Video
Hypomanic personality, stability of self-esteem and response styles to negative mood.
Clin Psychol Psychother
PUBLISHED: 09-02-2011
Show Abstract
Hide Abstract
This paper aims to study dysfunctional self-schematic processes, abnormal coping styles, over-responsiveness to reward stimuli (indicative of an over-sensitive behavioural activation system) and stability of self-esteem in relation to subclinical hypomania.
Related JoVE Video
Cardiac overexpression of 8-oxoguanine DNA glycosylase 1 protects mitochondrial DNA and reduces cardiac fibrosis following transaortic constriction.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 08-26-2011
Show Abstract
Hide Abstract
Cardiac failure is associated with increased levels of oxidized DNA, especially mitochondrial (mtDNA). It is not known if oxidized mtDNA contributes to cardiac dysfunction. To test if protection of mtDNA can reduce cardiac injury, we produced transgenic mice with cardiomyocyte-specific overexpression of the DNA repair enzyme 8-oxoguanine DNA glycosylase 1 (OGG1) isoform 2a. In one line of mice, the transgene increased OGG1 activity by 115% in mitochondria and by 28% in nuclei. OGG1 transgenic mice demonstrated significantly lower cardiac mitochondrial levels of the DNA guanine oxidation product 7,8-dihydro-8-oxoguanine (8-oxo-dG) under basal conditions, after doxorubicin administration, or after transaortic constriction (TAC), but the transgene produced no detectable reduction in nuclear 8-oxo-dG content. OGG1 mice were tested for protection from the cardiac effects of TAC 13 wk after surgery. Compared with FVB-TAC mice, hearts from OGG1-TAC mice had lower levels of ?-myosin heavy chain mRNA but they did not display significant differences in the ratio of heart weight to tibia length or protection of cardiac function measured by echocardiography. The principle benefit of OGG1 overexpression was a significant decrease in TAC-induced cardiac fibrosis. This protection was indicated by reduced Sirius red staining on OGG1 cardiac sections and by significantly decreased induction of collagen 1 and 3 mRNA expression in OGG1 hearts after TAC surgery. These results provide a new model to assess the damaging cardiac effects of 8-oxo-dG formation and suggest that increased repair of 8-oxo-dG in mtDNA decreases cardiac pathology.
Related JoVE Video
Concurrent CIC mutations, IDH mutations, and 1p/19q loss distinguish oligodendrogliomas from other cancers.
J. Pathol.
PUBLISHED: 08-24-2011
Show Abstract
Hide Abstract
Oligodendroglioma is characterized by unique clinical, pathological, and genetic features. Recurrent losses of chromosomes 1p and 19q are strongly associated with this brain cancer but knowledge of the identity and function of the genes affected by these alterations is limited. We performed exome sequencing on a discovery set of 16 oligodendrogliomas with 1p/19q co-deletion to identify new molecular features at base-pair resolution. As anticipated, there was a high rate of IDH mutations: all cases had mutations in either IDH1 (14/16) or IDH2 (2/16). In addition, we discovered somatic mutations and insertions/deletions in the CIC gene on chromosome 19q13.2 in 13/16 tumours. These discovery set mutations were validated by deep sequencing of 13 additional tumours, which revealed seven others with CIC mutations, thus bringing the overall mutation rate in oligodendrogliomas in this study to 20/29 (69%). In contrast, deep sequencing of astrocytomas and oligoastrocytomas without 1p/19q loss revealed that CIC alterations were otherwise rare (1/60; 2%). Of the 21 non-synonymous somatic mutations in 20 CIC-mutant oligodendrogliomas, nine were in exon 5 within an annotated DNA-interacting domain and three were in exon 20 within an annotated protein-interacting domain. The remaining nine were found in other exons and frequently included truncations. CIC mutations were highly associated with oligodendroglioma histology, 1p/19q co-deletion, and IDH1/2 mutation (p < 0.001). Although we observed no differences in the clinical outcomes of CIC mutant versus wild-type tumours, in a background of 1p/19q co-deletion, hemizygous CIC mutations are likely important. We hypothesize that the mutant CIC on the single retained 19q allele is linked to the pathogenesis of oligodendrogliomas with IDH mutation. Our detailed study of genetic aberrations in oligodendroglioma suggests a functional interaction between CIC mutation, IDH1/2 mutation, and 1p/19q co-deletion.
Related JoVE Video
Brief report: a family risk study exploring bipolar spectrum problems and cognitive biases in adolescent children of bipolar parents.
J Adolesc
PUBLISHED: 08-17-2011
Show Abstract
Hide Abstract
Children of parents with bipolar disorder are at increased risk of bipolar spectrum diagnoses. This cross-sectional study explores cognitive factors in the prediction of vulnerability to bipolar disorder. Adolescents at high-risk (with a parent with bipolar disorder; n = 23) and age and gender matched adolescents (n = 24) were recruited. Parent and adolescent diagnoses were evaluated (SCID and SADS-L). Adolescents completed self-report measures assessing attributional style (ASQ), appraisal of hypomania-relevant experiences (HIQ), and hypomanic personality/temperament (HPS). Despite limitations in the power of the study, significantly more adolescents at high-risk for disorder received bipolar spectrum diagnoses. Groups did not differ in attributional style, hypomanic temperament or appraisals of hypomania-relevant experiences. A trend in ASQ results and general implications are discussed. The current study suggests that familial risk of bipolar disorder is not inevitably associated with cognitive biases in adolescence.
Related JoVE Video
Using next-generation sequencing for the diagnosis of rare disorders: a family with retinitis pigmentosa and skeletal abnormalities.
J. Pathol.
PUBLISHED: 07-28-2011
Show Abstract
Hide Abstract
Linkage analysis with subsequent candidate gene sequencing is typically used to diagnose novel inherited syndromes. It is now possible to expedite diagnosis through the sequencing of all coding regions of the genome (the exome) or full genomes. We sequenced the exomes of four members of a family presenting with spondylo-epiphyseal dysplasia and retinitis pigmentosa and identified a six-base-pair (6-bp) deletion in GNPTG, the gene implicated in mucolipidosis type III?. The diagnosis was confirmed by biochemical studies and both broadens the mucolipidosis type III phenotype and demonstrates the clinical utility of next-generation sequencing to diagnose rare genetic diseases.
Related JoVE Video
A new frontier in personalized cancer therapy: mapping molecular changes.
Future Oncol
PUBLISHED: 07-08-2011
Show Abstract
Hide Abstract
Mutations in the genome of a normal cell can affect the function of its many genes and pathways. These alterations could eventually transform the cell from a normal to a malignant state by allowing an uncontrolled proliferation of the cell and formation of a cancer tumor. Each tumor in an individual patient can have hundreds of mutated genes and perturbed pathways. Cancers clinically presenting as the same type or subtype could potentially be very different at the molecular level and thus behave differently in response to therapy. The challenge is to distinguish the key mutations driving the cancer from the background of mutational noise and find ways to effectively target them. The promise is that such a molecular approach to classifying cancer will lead to better diagnostic, prognostic and personalized treatment strategies. This article provides an overview of advances in the molecular characterization of cancers and their applications in therapy.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.