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1.
Public Health Action ; 14(2): 76-81, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38957503

ABSTRACT

OBJECTIVE: To identify individual-level early warning indicators of virologic failure in HIV patients receiving antiretroviral therapy (ART) in South Africa. DESIGN: A matched case-control study of individuals with and without virologic failure (VF) (>5 months on ART and HIV-1 plasma viral load >1,000 copies/mL) was conducted between June 2014 and June 2018. Of the 1,000 participants enrolled in the parent cohort, 96 experienced VF, and 199 additional controls were identified from the parent cohort and matched 1:2 (some matched 1:3) for sex, age, ART duration, and site. Participants were interviewed while clinical, pharmacy refill, laboratory, and objective pharmacological data were obtained. Multivariate conditional logistic regression models were constructed using model selection to identify factors associated with VF. Significant determinants of VF were identified using an alpha level of 0.05. RESULTS: In a full conditional model, higher cumulative ART adherence, quantified using tenofovir-diphosphate concentrations in dried blood spots (OR 0.26) and medication possession ratio (OR 0.98) were protective against VF, whereas an increase in total depression score (OR 1.20) was predictive of VF. CONCLUSION: This analysis demonstrates the importance of depression as a key individual-level early warning indicator of VF. Efforts to address mental health concerns among patients with people living with HIV could improve virologic suppression.


OBJECTIF: Identifier les indicateurs d'alerte précoce au niveau individuel de l'échec virologique chez les patients séropositifs recevant un traitement antirétroviral (TAR) en Afrique du Sud. MÉTHODE: Une étude cas-témoins appariée de personnes avec et sans échec virologique (FV, pour l'anglais « virologic failure ¼) (>5 mois sous ART et charge virale plasmatique du VIH-1 >1 000 copies/ml) a été menée entre juin 2014 et juin 2018. Sur les 1 000 participants inscrits dans la cohorte parente, 96 ont présenté une FV et 199 témoins supplémentaires ont été identifiés dans la cohorte parentale et appariés 1:2 (certains appariés 1:3) pour le sexe, l'âge, la durée du TAR et le site. Les participants ont été interrogés pendant que des données cliniques, de renouvellement de pharmacie, de laboratoire et pharmacologiques objectives ont été obtenues. Des modèles de régression logistique conditionnelle multivariée ont été construits à l'aide d'une sélection de modèles pour identifier les facteurs associés à la FV. Les déterminants significatifs de la FV ont été identifiés à l'aide d'un niveau alpha de 0,05. RÉSULTATS: Dans un modèle conditionnel complet, une observance cumulative plus élevée du TAR, quantifiée à l'aide des concentrations de ténofovir-diphosphate dans les gouttes de sang séché (OR 0,26) et du ratio de possession de médicaments (OR 0,98) protégeait contre la FV, tandis qu'une augmentation du score de dépression totale (OR 1,20) était prédictive de la FV. CONCLUSION: Cette analyse démontre l'importance de la dépression en tant qu'indicateur précoce clé au niveau individuel de la FV. Les efforts visant à résoudre les problèmes de santé mentale chez les personnes vivant avec le VIH pourraient améliorer la suppression virologique.

2.
Public Health Action ; 13(4): 119-122, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38077728

ABSTRACT

Self-testing for COVID-19 using antigen-detecting rapid diagnostic tests (Ag-RDTs) shows high promise in the Philippines. Self-testing has the potential to provide broader access to testing, empowering individuals by bringing healthcare services closer to them. We conducted 15 semi-structured interviews with health officers and decision-makers in the Philippines. These interviews explored the experiences and perspectives on the acceptability and feasibility of self-test use and implementation. We found that self-testing is easy-to-use, provides rapid results and can facilitate early detection. However, -regulatory policies, linkages to care and effective health -education plans must be in place for successful implementation.

4.
Dis Aquat Organ ; 144: 245-252, 2021 May 27.
Article in English | MEDLINE | ID: mdl-34042072

ABSTRACT

Processes that allow viral hemorrhagic septicemia (VHS) virus to persist in the marine environment remain enigmatic, owing largely to the presence of covert and cryptic infections in marine fishes during typical sub-epizootic periods. As such, marine host reservoirs for VHS virus have not been fully demonstrated, nor have the mechanism(s) by which infected hosts contribute to virus perpetuation and transmission. Here, we demonstrate that after surviving VHS, convalesced Pacific herring continue to shed virus at a low rate for extended periods. Further, exposure of previously naïve conspecific sentinels to this shed virus can result in infections for at least 6 mo after cessation of overt disease. This transmission mechanism was not necessarily dependent on the magnitude of the disease outbreak, as prolonged transmission occurred from 2 groups of donor herring that experienced cumulative mortalities of 4 and 29%. The results further suggest that the virus persists in association with the gills of fully recovered individuals, and long-term viral shedding or shedding relapses are related to cooler or decreasing water temperatures. These results provide support for a new VHS virus perpetuation paradigm in the marine environment, whereby the virus can be maintained in convalesced survivors and trafficked from these carriers to sympatric susceptible individuals.


Subject(s)
Fish Diseases , Hemorrhagic Septicemia, Viral , Novirhabdovirus , Animals , Disease Outbreaks , Fish Diseases/epidemiology , Fishes , Virus Shedding
5.
Nat Rev Cancer ; 20(3): 174-186, 2020 03.
Article in English | MEDLINE | ID: mdl-31980749

ABSTRACT

Cancer-associated fibroblasts (CAFs) are a key component of the tumour microenvironment with diverse functions, including matrix deposition and remodelling, extensive reciprocal signalling interactions with cancer cells and crosstalk with infiltrating leukocytes. As such, they are a potential target for optimizing therapeutic strategies against cancer. However, many challenges are present in ongoing attempts to modulate CAFs for therapeutic benefit. These include limitations in our understanding of the origin of CAFs and heterogeneity in CAF function, with it being desirable to retain some antitumorigenic functions. On the basis of a meeting of experts in the field of CAF biology, we summarize in this Consensus Statement our current knowledge and present a framework for advancing our understanding of this critical cell type within the tumour microenvironment.


Subject(s)
Cancer-Associated Fibroblasts/metabolism , Cancer-Associated Fibroblasts/pathology , Neoplasms/etiology , Neoplasms/pathology , Tumor Microenvironment , Animals , Biomarkers , Cancer-Associated Fibroblasts/drug effects , Cell Plasticity , Clinical Trials as Topic , Disease Susceptibility , Humans , Molecular Targeted Therapy , Neoplasms/drug therapy , Neoplasms/metabolism , Signal Transduction , Stromal Cells/drug effects , Stromal Cells/metabolism , Stromal Cells/pathology , Treatment Outcome
6.
J Aquat Anim Health ; 31(3): 259-265, 2019 09.
Article in English | MEDLINE | ID: mdl-31107989

ABSTRACT

An analysis of daily water samples collected from an index site on Big Soos Creek, Washington indicated intra-annual differences in the concentrations of waterborne Nanophyetus salmincola. Waterborne concentrations, quantified as gene copies/L, peaked during the fall (October-November 2016), decreased to very low concentrations over the winter (January-March 2017), and then increased in the spring and throughout the summer. High waterborne concentrations of N. salmincola DNA (2 × 106 gene copies/L) corresponded with live N. salmincola cercariae (mean = 3 cercariae/L) that were detected in companion water samples. Spikes in waterborne N. salmincola concentrations in October and November typically coincided with increases in streamflow; this combination resulted in elevated infection pressures during high water events in the fall. The peak in waterborne N. salmincola concentrations corresponded with an accompanying peak in tissue parasite density (metacercariae/posterior kidney) in Coho Salmon Oncorhynchus kisutch that were reared in the untreated water.


Subject(s)
Fish Diseases/epidemiology , Oncorhynchus kisutch , Rivers/parasitology , Trematoda/physiology , Trematode Infections/veterinary , Animals , Cercaria/physiology , Fish Diseases/parasitology , Population Dynamics , Prevalence , Seasons , Trematoda/growth & development , Trematode Infections/epidemiology , Trematode Infections/parasitology , Washington
7.
J Fish Dis ; 41(2): 347-355, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29159930

ABSTRACT

This research was initiated in conjunction with a systematic, multiagency surveillance effort in the United States (U.S.) in response to reported findings of infectious salmon anaemia virus (ISAV) RNA in British Columbia, Canada. In the systematic surveillance study reported in a companion paper, tissues from various salmonids taken from Washington and Alaska were surveyed for ISAV RNA using the U.S.-approved diagnostic method, and samples were released for use in this present study only after testing negative. Here, we tested a subset of these samples for ISAV RNA with three additional published molecular assays, as well as for RNA from salmonid alphavirus (SAV), piscine myocarditis virus (PMCV) and piscine orthoreovirus (PRV). All samples (n = 2,252; 121 stock cohorts) tested negative for RNA from ISAV, PMCV, and SAV. In contrast, there were 25 stock cohorts from Washington and Alaska that had one or more individuals test positive for PRV RNA; prevalence within stocks varied and ranged from 2% to 73%. The overall prevalence of PRV RNA-positive individuals across the study was 3.4% (77 of 2,252 fish tested). Findings of PRV RNA were most common in coho (Oncorhynchus kisutch Walbaum) and Chinook (O. tshawytscha Walbaum) salmon.


Subject(s)
Fish Diseases/epidemiology , Orthoreovirus/isolation & purification , Reoviridae Infections/veterinary , Salmon , Trout , Alaska/epidemiology , Animals , Fish Diseases/virology , Orthoreovirus/genetics , Polymerase Chain Reaction/veterinary , RNA, Viral/analysis , Reoviridae Infections/epidemiology , Reoviridae Infections/virology , Washington/epidemiology
8.
J Perinatol ; 37(4): 349-354, 2017 04.
Article in English | MEDLINE | ID: mdl-28005062

ABSTRACT

OBJECTIVE: Delivery room management interventions have been successfully implemented via collaborative quality improvement (QI) projects. However, it is unknown whether these successes translate to reductions in neonatal morbidity and mortality. STUDY DESIGN: This was a prospective pre-post intervention study of three nonrandomized hospital groups within the California Perinatal Quality Care Collaborative. A collaborative QI model (Collaborative QI) was compared with a single-site QI model (NICU QI) and a non-participant population when implementing evidence-based delivery room practices. The intervention period was between June 2011 and May 2012. Infants born with gestational age between 22 weeks 0 days and 29 weeks 6 days and birth weight ⩽1500 g were included. Outcomes were mortality and select morbidities (bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP) and necrotizing enterocolitis (NEC)). Outcomes were compared between the baseline (January 2010 to May 2011) and post-intervention period (June 2012 to May 2013) within each comparison group. RESULTS: Ninety-five hospitals were included with 4222 infants in the baseline period and 4186 infants in the post-intervention period. The Collaborative QI group had significantly reduced odds of developing BPD post-intervention (odds ratio (OR) 0.8, 95% confidence interval (CI) 0.65 to 0.99) or composite BPD-death (OR 0.83, 95% CI 0.69 to 1.00). In both the Collaborative QI and non-participants there were also reductions in IVH, severe IVH, composite severe IVH-death, severe ROP and composite severe ROP-death. CONCLUSION: Hospitals dedicated to improving delivery room practices can impact neonatal outcomes.


Subject(s)
Delivery Rooms/organization & administration , Infant Mortality , Infant, Extremely Premature , Quality Improvement , Birth Weight , Bronchopulmonary Dysplasia/mortality , California/epidemiology , Cerebral Hemorrhage/mortality , Enterocolitis, Necrotizing/mortality , Female , Gestational Age , Humans , Infant , Infant, Newborn , Infant, Very Low Birth Weight , Male , Multivariate Analysis , Pregnancy , Prospective Studies , Regression Analysis , Retinopathy of Prematurity/mortality
9.
Bioinformatics ; 32(6): 926-8, 2016 03 15.
Article in English | MEDLINE | ID: mdl-26576652

ABSTRACT

UNLABELLED: In this article, we introduce a robust and efficient strategy for deriving global and allele-specific copy number alternations (CNA) from cancer whole exome sequencing data based on Log R ratios and B-allele frequencies. Applying the approach to the analysis of over 200 skin cancer samples, we demonstrate its utility for discovering distinct CNA events and for deriving ancillary information such as tumor purity. AVAILABILITY AND IMPLEMENTATION: https://github.com/xfwang/CLOSE CONTACT: xuefeng.wang@stonybrook.edu or michael.krauthammer@yale.edu SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
DNA Copy Number Variations , Algorithms , Gene Frequency , Genome, Human , Humans , Neoplasms , Sequence Analysis, DNA
10.
Mol Cell ; 60(4): 571-83, 2015 Nov 19.
Article in English | MEDLINE | ID: mdl-26481663

ABSTRACT

Phosphoenolpyruvate carboxykinase (PEPCK) is well known for its role in gluconeogenesis. However, PEPCK is also a key regulator of TCA cycle flux. The TCA cycle integrates glucose, amino acid, and lipid metabolism depending on cellular needs. In addition, biosynthetic pathways crucial to tumor growth require the TCA cycle for the processing of glucose and glutamine derived carbons. We show here an unexpected role for PEPCK in promoting cancer cell proliferation in vitro and in vivo by increasing glucose and glutamine utilization toward anabolic metabolism. Unexpectedly, PEPCK also increased the synthesis of ribose from non-carbohydrate sources, such as glutamine, a phenomenon not previously described. Finally, we show that the effects of PEPCK on glucose metabolism and cell proliferation are in part mediated via activation of mTORC1. Taken together, these data demonstrate a role for PEPCK that links metabolic flux and anabolic pathways to cancer cell proliferation.


Subject(s)
Colorectal Neoplasms/pathology , Glucose/metabolism , Glutamine/metabolism , Multiprotein Complexes/metabolism , Phosphoenolpyruvate Carboxykinase (ATP)/metabolism , TOR Serine-Threonine Kinases/metabolism , Animals , Cell Line, Tumor , Cell Proliferation , Colorectal Neoplasms/metabolism , Glycolysis , HT29 Cells , Humans , Mechanistic Target of Rapamycin Complex 1 , Mice , Neoplasm Transplantation
12.
Bioinformatics ; 31(12): 2040-2, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25681254

ABSTRACT

UNLABELLED: Currently available bisulfite sequencing tools frequently suffer from low mapping rates and low methylation calls, especially for data generated from the Illumina sequencer, NextSeq. Here, we introduce a sequential trimming-and-retrieving alignment approach for investigating DNA methylation patterns, which significantly improves the number of mapped reads and covered CpG sites. The method is implemented in an automated analysis toolkit for processing bisulfite sequencing reads. AVAILABILITY AND IMPLEMENTATION: http://mysbfiles.stonybrook.edu/~xuefenwang/software.html and https://github.com/xfwang/BStools.


Subject(s)
DNA Methylation , High-Throughput Nucleotide Sequencing/methods , Sequence Alignment/methods , Sequence Analysis, DNA/methods , Software , Sulfites/chemistry , Humans
13.
Placenta ; 35(9): 763-71, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25002363

ABSTRACT

INTRODUCTION: Shallow trophoblast invasion of the maternal spiral arteries contributes to impaired placental perfusion and is hypothesized to be involved in the pathophysiology of preeclampsia. Hypoxia is a potent stimulus for the release of adenosine. METHODS: We investigated the effects of hypoxia and A2B adenosine receptor signaling on migration, invasion, proteolytic activity of matrix metalloproteinase (MMP)-2, expression of MMP-2 and vascular endothelial growth factor (VEGF) mRNA, and production of human chorionic gonadotropin (hCG) in trophoblast cells (HTR-8/SVneo, BeWo). RESULTS: The adenosine A2B receptor agonist 5-N-ethylcarboxamidoadenosine (NECA) reduced trophoblast (HTR-8/SVneo and BeWo) migration at 2%, 8% and 21% O2 compared to untreated control cells. A2B adenosine receptor stimulation decreased phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and stress-activated protein kinase/Jun-amino-terminal kinase (SAPK/JNK) at all three O2 concentrations. ProMMP-2 activity, MMP-2 mRNA levels and hCG levels were markedly decreased after A2B adenosine receptor activation in trophoblast cells. Adenosine receptor A2B stimulation decreased VEGF expression at 2% and 8% O2 but led to increased levels at 21% O2. CONCLUSIONS: These data indicate A2B receptor activation blunts trophoblast migration possibly as a result of reduced activation of the MAPK signaling pathway and lower proMMP-2 levels. These data suggest a role for adenosine receptor A2B in placental development and possibly in the pathophysiology of preeclampsia.


Subject(s)
MAP Kinase Signaling System , Mitogen-Activated Protein Kinases/metabolism , Receptor, Adenosine A2B/metabolism , Trophoblasts/metabolism , Cell Line , Cell Movement , Chorionic Gonadotropin/metabolism , Female , Humans , Matrix Metalloproteinase 2/metabolism , Oxygen/metabolism , Pre-Eclampsia/etiology , Pregnancy , Vascular Endothelial Growth Factor A/metabolism
14.
Nat Commun ; 5: 3729, 2014 Apr 23.
Article in English | MEDLINE | ID: mdl-24759783

ABSTRACT

Mounting evidence indicates that oncogenic Ras can modulate cell autonomous inflammatory cytokine production, although the underlying mechanism remains unclear. Here we show that squamous cell carcinoma antigens 1 and 2 (SCCA1/2), members of the Serpin family of serine/cysteine protease inhibitors, are transcriptionally upregulated by oncogenic Ras via MAPK and the ETS family transcription factor PEA3. Increased SCCA expression leads to inhibition of protein turnover, unfolded protein response, activation of NF-κB and is essential for Ras-mediated cytokine production and tumour growth. Analysis of human colorectal and pancreatic tumour samples reveals a positive correlation between Ras mutation, enhanced SCCA expression and IL-6 expression. These results indicate that SCCA is a Ras-responsive factor that plays an important role in Ras-associated cytokine production and tumorigenesis.


Subject(s)
Antigens, Neoplasm/metabolism , Cytokines/biosynthesis , Inflammation Mediators/metabolism , Proto-Oncogene Proteins p21(ras)/physiology , Serpins/metabolism , Up-Regulation , Humans
15.
J Neurophysiol ; 111(10): 2017-28, 2014 May.
Article in English | MEDLINE | ID: mdl-24572092

ABSTRACT

Stroke survivors often exhibit abnormally low motor unit firing rates during voluntary muscle activation. Our purpose was to assess the prevalence of saturation in motor unit firing rates in the spastic-paretic biceps brachii muscle of stroke survivors. To achieve this objective, we recorded the incidence and duration of impaired lower- and higher-threshold motor unit firing rate modulation in spastic-paretic, contralateral, and healthy control muscle during increases in isometric force generated by the elbow flexor muscles. Impaired firing was considered to have occurred when firing rate became constant (i.e., saturated), despite increasing force. The duration of impaired firing rate modulation in the lower-threshold unit was longer for spastic-paretic (3.9 ± 2.2 s) than for contralateral (1.4 ± 0.9 s; P < 0.001) and control (1.1 ± 1.0 s; P = 0.005) muscles. The duration of impaired firing rate modulation in the higher-threshold unit was also longer for the spastic-paretic (1.7 ± 1.6 s) than contralateral (0.3 ± 0.3 s; P = 0.007) and control (0.1 ± 0.2 s; P = 0.009) muscles. This impaired firing rate of the lower-threshold unit arose, despite an increase in the overall descending command, as shown by the recruitment of the higher-threshold unit during the time that the lower-threshold unit was saturating, and by the continuous increase in averages of the rectified EMG of the biceps brachii muscle throughout the rising phase of the contraction. These results suggest that impairments in firing rate modulation are prevalent in motor units of spastic-paretic muscle, even when the overall descending command to the muscle is increasing.


Subject(s)
Muscle Contraction/physiology , Muscle Spasticity/physiopathology , Muscle, Skeletal/physiopathology , Paresis/physiopathology , Recruitment, Neurophysiological/physiology , Stroke/physiopathology , Action Potentials , Aged , Elbow , Electromyography , Female , Humans , Male , Middle Aged , Motor Activity/physiology
16.
PLoS Genet ; 9(9): e1003789, 2013.
Article in English | MEDLINE | ID: mdl-24068959

ABSTRACT

Many fibroblast-secreted proteins promote tumorigenicity, and several factors secreted by cancer cells have in turn been proposed to induce these proteins. It is not clear whether there are single dominant pathways underlying these interactions or whether they involve multiple pathways acting in parallel. Here, we identified 42 fibroblast-secreted factors induced by breast cancer cells using comparative genomic analysis. To determine what fraction was active in promoting tumorigenicity, we chose five representative fibroblast-secreted factors for in vivo analysis. We found that the majority (three out of five) played equally major roles in promoting tumorigenicity, and intriguingly, each one had distinct effects on the tumor microenvironment. Specifically, fibroblast-secreted amphiregulin promoted breast cancer cell survival, whereas the chemokine CCL7 stimulated tumor cell proliferation while CCL2 promoted innate immune cell infiltration and angiogenesis. The other two factors tested had minor (CCL8) or minimally (STC1) significant effects on the ability of fibroblasts to promote tumor growth. The importance of parallel interactions between fibroblasts and cancer cells was tested by simultaneously targeting fibroblast-secreted amphiregulin and the CCL7 receptor on cancer cells, and this was significantly more efficacious than blocking either pathway alone. We further explored the concept of parallel interactions by testing the extent to which induction of critical fibroblast-secreted proteins could be achieved by single, previously identified, factors produced by breast cancer cells. We found that although single factors could induce a subset of genes, even combinations of factors failed to induce the full repertoire of functionally important fibroblast-secreted proteins. Together, these results delineate a complex network of tumor-fibroblast interactions that act in parallel to promote tumorigenicity and suggest that effective anti-stromal therapeutic strategies will need to be multi-targeted.


Subject(s)
Breast Neoplasms/genetics , Carcinogenesis , Cell Proliferation , Fibroblasts/metabolism , Tumor Microenvironment/genetics , Amphiregulin , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Movement/genetics , Chemokine CCL2 , Chemokine CCL7/genetics , Chemokine CCL7/metabolism , Coculture Techniques , EGF Family of Proteins , Female , Fibroblasts/pathology , Glycoproteins/genetics , Glycoproteins/metabolism , Humans , Intercellular Signaling Peptides and Proteins/genetics , Intercellular Signaling Peptides and Proteins/metabolism
17.
PLoS One ; 8(6): e66264, 2013.
Article in English | MEDLINE | ID: mdl-23805207

ABSTRACT

One of the key questions about genomic alterations in cancer is whether they are functional in the sense of contributing to the selective advantage of tumor cells. The frequency with which an alteration occurs might reflect its ability to increase cancer cell growth, or alternatively, enhanced instability of a locus may increase the frequency with which it is found to be aberrant in tumors, regardless of oncogenic impact. Here we've addressed this on a genome-wide scale for cancer-associated focal deletions, which are known to pinpoint both tumor suppressor genes (tumor suppressors) and unstable loci. Based on DNA copy number analysis of over one-thousand human cancers representing ten different tumor types, we observed five loci with focal deletion frequencies above 5%, including the A2BP1 gene at 16p13.3 and the MACROD2 gene at 20p12.1. However, neither RNA expression nor functional studies support a tumor suppressor role for either gene. Further analyses suggest instead that these are sites of increased genomic instability and that they resemble common fragile sites (CFS). Genome-wide analysis revealed properties of CFS-like recurrent deletions that distinguish them from deletions affecting tumor suppressor genes, including their isolation at specific loci away from other genomic deletion sites, a considerably smaller deletion size, and dispersal throughout the affected locus rather than assembly at a common site of overlap. Additionally, CFS-like deletions have less impact on gene expression and are enriched in cell lines compared to primary tumors. We show that loci affected by CFS-like deletions are often distinct from known common fragile sites. Indeed, we find that each tumor tissue type has its own spectrum of CFS-like deletions, and that colon cancers have many more CFS-like deletions than other tumor types. We present simple rules that can pinpoint focal deletions that are not CFS-like and more likely to affect functional tumor suppressors.


Subject(s)
Genome/genetics , Neoplasms/genetics , Sequence Deletion , Animals , Cell Line, Tumor , Chromosome Fragile Sites/genetics , Chromosome Mapping , Chromosomes/genetics , Chromosomes/metabolism , Comparative Genomic Hybridization , DNA Repair Enzymes/genetics , Humans , Hydrolases/genetics , Mice , Neoplasms/physiopathology , RNA Splicing Factors/genetics , Real-Time Polymerase Chain Reaction , Transplantation, Heterologous
18.
Proc Natl Acad Sci U S A ; 110(11): 4245-50, 2013 Mar 12.
Article in English | MEDLINE | ID: mdl-23431203

ABSTRACT

Large-scale integrated cancer genome characterization efforts including the cancer genome atlas and the cancer cell line encyclopedia have created unprecedented opportunities to study cancer biology in the context of knowing the entire catalog of genetic alterations. A clinically important challenge is to discover cancer subtypes and their molecular drivers in a comprehensive genetic context. Curtis et al. [Nature (2012) 486(7403):346-352] has recently shown that integrative clustering of copy number and gene expression in 2,000 breast tumors reveals novel subgroups beyond the classic expression subtypes that show distinct clinical outcomes. To extend the scope of integrative analysis for the inclusion of somatic mutation data by massively parallel sequencing, we propose a framework for joint modeling of discrete and continuous variables that arise from integrated genomic, epigenomic, and transcriptomic profiling. The core idea is motivated by the hypothesis that diverse molecular phenotypes can be predicted by a set of orthogonal latent variables that represent distinct molecular drivers, and thus can reveal tumor subgroups of biological and clinical importance. Using the cancer cell line encyclopedia dataset, we demonstrate our method can accurately group cell lines by their cell-of-origin for several cancer types, and precisely pinpoint their known and potential cancer driver genes. Our integrative analysis also demonstrates the power for revealing subgroups that are not lineage-dependent, but consist of different cancer types driven by a common genetic alteration. Application of the cancer genome atlas colorectal cancer data reveals distinct integrated tumor subtypes, suggesting different genetic pathways in colon cancer progression.


Subject(s)
Breast Neoplasms/genetics , Colorectal Neoplasms/genetics , Databases, Genetic , Epigenomics , Gene Expression Regulation , Genes, Neoplasm , Genomics/methods , Breast Neoplasms/metabolism , Colorectal Neoplasms/metabolism , Female , Humans , Male
19.
Cancer Discov ; 2(9): 812-25, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22750847

ABSTRACT

UNLABELLED: Understanding factors required for DNA replication will enrich our knowledge of this important process and potentially identify vulnerabilities that can be exploited in cancer therapy. We applied an assay that measures the stability of maintenance of an episomal plasmid in human tissue culture cells to screen for new DNA replication factors. We identify an important role for DDX5 in G(1)-S-phase progression where it directly regulates DNA replication factor expression by promoting the recruitment of RNA polymerase II to E2F-regulated gene promoters. We find that the DDX5 locus is frequently amplified in breast cancer and that breast cancer-derived cells with amplification of DDX5 are much more sensitive to its depletion than breast cancer cells and a breast epithelial cell line that lacks DDX5 amplification. Our results show a novel role for DDX5 in cancer cell proliferation and suggest DDX5 as a therapeutic target in breast cancer treatment. SIGNIFICANCE: DDX5 is required for cell proliferation by controlling the transcription of genes expressing DNA replication proteins in cancer cells in which the DDX5 locus is amplified, and this has uncovered a dependence on DDX5 for cell proliferation. Given the high frequency of DDX5 amplification in breast cancer, our results highlight DDX5 as a promising candidate for targeted therapy of breast tumors with DDX5 amplification, and indeed we show that DDX5 inhibition sensitizes a subset of breast cancer cells to trastuzumab.


Subject(s)
Breast Neoplasms/genetics , DEAD-box RNA Helicases/genetics , DNA Replication , DNA, Neoplasm/biosynthesis , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Growth Processes/genetics , Cell Line, Tumor , DEAD-box RNA Helicases/metabolism , DNA, Neoplasm/genetics , Female , Gene Amplification , Gene Expression Regulation, Neoplastic , HCT116 Cells , Humans , Molecular Targeted Therapy , Plasmids/genetics , Promoter Regions, Genetic , RNA Polymerase II/metabolism , S Phase/genetics
20.
Nat Rev Cancer ; 12(8): 572-8, 2012 08.
Article in English | MEDLINE | ID: mdl-22739505

ABSTRACT

The analysis of human cancer by genome sequencing and various types of arrays has proved that many tumours harbour hundreds of genes that are mutated or substantially altered by copy number changes. But how many of these changes are meaningful? And how can we exploit these massive data sets to yield new targets for cancer treatment? In this Opinion article, we describe emerging approaches that aim to determine which altered genes are actually contributing to cancer, as well as their potential as therapeutic targets.


Subject(s)
Cell Transformation, Neoplastic/genetics , Mutation , Neoplasms/genetics , Animals , Genome , Humans , Molecular Targeted Therapy/methods , Neoplasms/therapy
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