Sundaram P.,Children's Hospital of Philadelphia |
Hultine S.,Children's Hospital of Philadelphia |
Smith L.M.,University of Pennsylvania |
Dews M.,Children's Hospital of Philadelphia |
And 10 more authors.
Cancer Research | Year: 2011
Thrombospondin-1 (TSP-1) is an endogenous inhibitor of angiogenesis encoded by the THBS1 gene, whose promoter is activated by p53. In advanced colorectal cancers (CRC), its expression is sustained or even slightly increased despite frequent loss of p53. Here, we determined that in HCT116 CRC cells, p53 activates the THBS1 primary transcript, but fails to boost THBS1 mRNA or protein levels, implying posttranscriptional regulation by microRNAs (miRNA). In a global miRNA gain-of-function screen done in the Dicer-deficient HCT116 variant, several miRNAs negatively regulated THBS1 mRNA and protein levels, one of them being miR-194. Notably, in agreement with published data, p53 upregulated miR-194 expression in THBS1 retrovirus-transduced HCT116 cells, leading to decreased TSP-1 levels. This negative effect was mediated by a single miR-194 complementary site in the THBS1 3′-untranslated region, and its elimination resulted in TSP-1 reactivation, impaired angiogenesis in Matrigel plugs, and reduced growth of HCT116 xenografts. Conversely, transient overexpression of miR-194 in HCT116/THBS1 cells boosted Matrigel angiogenesis, and its stable overexpression in Ras-induced murine colon carcinomas increased microvascular densities and vessel sizes. Although the overall contribution of miR-194 to neoplastic growth is context dependent, p53-induced activation of this GI tract-specific miRNA during ischemia could promote angiogenesis and facilitate tissue repair. ©2011 AACR.
Deng W.,University of Washington |
Maust B.S.,University of Washington |
Nickle D.C.,University of Washington |
Nickle D.C.,Rosetta Inpharmatics LLC |
And 6 more authors.
BioTechniques | Year: 2010
DIVEIN is a web interface that performs automated phylogenetic and other analyses of nucleotide and amino acid sequences. Starting with a set of aligned sequences, DIVEIN estimates evolutionary parameters and phylogenetic trees while allowing the user to choose from a variety of evolutionary models; it then reconstructs the consensus (CON), most recent common ancestor (MRCA), and center of tree (COT) sequences. DIVEIN also provides tools for further analyses, including condensing sequence alignments to show only informative sites or private mutations; computing phylogenetic or pairwise divergence from any user-specified sequence (CON, MRCA, COT, or existing sequence from the alignment); computing and outputting all genetic distances in column format; calculating summary statistics of diversity and divergence from pairwise distances; and graphically representing the inferred tree and plots of divergence, diversity, and distance distribution histograms. DIVEIN is available at http://indra.mullins.microbiol.washington.edu/DIVEIN.
Pandey G.,University of Minnesota |
Pandey G.,University of California at Berkeley |
Zhang B.,Rosetta Inpharmatics LLC |
Chang A.N.,Rosetta Inpharmatics LLC |
And 6 more authors.
PLoS Computational Biology | Year: 2010
Genetic interactions occur when a combination of mutations results in a surprising phenotype. These interactions capture functional redundancy, and thus are important for predicting function, dissecting protein complexes into functional pathways, and exploring the mechanistic underpinnings of common human diseases. Synthetic sickness and lethality are the most studied types of genetic interactions in yeast. However, even in yeast, only a small proportion of gene pairs have been tested for genetic interactions due to the large number of possible combinations of gene pairs. To expand the set of known synthetic lethal (SL) interactions, we have devised an integrative, multi-network approach for predicting these interactions that significantly improves upon the existing approaches. First, we defined a large number of features for characterizing the relationships between pairs of genes from various data sources. In particular, these features are independent of the known SL interactions, in contrast to some previous approaches. Using these features, we developed a non-parametric multi-classifier system for predicting SL interactions that enabled the simultaneous use of multiple classification procedures. Several comprehensive experiments demonstrated that the SL-independent features in conjunction with the advanced classification scheme led to an improved performance when compared to the current state of the art method. Using this approach, we derived the first yeast transcription factor genetic interaction network, part of which was well supported by literature. We also used this approach to predict SL interactions between all non-essential gene pairs in yeast (http://sage.fhcrc.org/downloads/downloads/predicted_yeast_genetic_interactions.zip). This integrative approach is expected to be more effective and robust in uncovering new genetic interactions from the tens of millions of unknown gene pairs in yeast and from the hundreds of millions of gene pairs in higher organisms like mouse and human, in which very few genetic interactions have been identified to date. © 2010 Pandey et al.
Hirakawa H.,University of Washington |
Oda Y.,University of Washington |
Phattarasukol S.,University of Washington |
Armour C.D.,Rosetta Inpharmatics LLC |
And 9 more authors.
Journal of Bacteriology | Year: 2011
The Rhodopseudomonas palustris transcriptional regulator RpaR responds to the RpaI-synthesized quorumsensing signal p-coumaroyl-homoserine lactone (pC-HSL). Other characterized RpaR homologs respond to fatty acyl-HSLs. We show here that RpaR functions as a transcriptional activator, which binds directly to the rpaI promoter. We developed an RNAseq method that does not require a ribosome depletion step to define a set of transcripts regulated by pC-HSL and RpaR. The transcripts include several noncoding RNAs. A footprint analysis showed that purified His-tagged RpaR (His6-RpaR) binds to an inverted repeat element centered 48.5 bp upstream of the rpaI transcript start site, which we mapped by S1 nuclease protection and primer extension analyses. Although pC-HSL-RpaR bound to rpaI promoter DNA, it did not bind to the promoter regions of a number of RpaR-regulated genes not in the rpaI operon. This indicates that RpaR control of these other genes is indirect. Because the RNAseq analysis allowed us to track transcript strand specificity, we discovered that there is pC-HSL-RpaR-activated antisense transcription of rpaR. These data raise the possibility that this antisense RNA or other RpaR-activated noncoding RNAs mediate the indirect activation of genes in the RpaR-controlled regulon. © 2011, American Society for Microbiology.
Mathieu J.,University of Washington |
Zhang Z.,Rosetta Inpharmatics LLC |
Zhou W.,University of Washington |
Wang A.J.,University of Washington |
And 18 more authors.
Cancer Research | Year: 2011
Low oxygen levels have been shown to promote self-renewal in many stem cells. In tumors, hypoxia is associated with aggressive disease course and poor clinical outcomes. Furthermore, many aggressive tumors have been shown to display gene expression signatures characteristic of human embryonic stem cells (hESC). We now tested whether hypoxia might be responsible for the hESC signature observed in aggressive tumors. We show that hypoxia, through hypoxia-inducible factor (HIF), can induce an hESC-like transcriptional program, including the induced pluripotent stem cell (iPSC) inducers, OCT4, NANOG, SOX2, KLF4, cMYC, and microRNA-302 in 11 cancer cell lines (from prostate, brain, kidney, cervix, lung, colon, liver, and breast tumors). Furthermore, nondegradable forms of HIFa, combined with the traditional iPSC inducers, are highly efficient in generating A549 iPSC-like colonies that have high tumorigenic capacity. To test potential correlation between iPSC inducers and HIF expression in primary tumors, we analyzed primary prostate tumors and found a significant correlation between NANOG-, OCT4-, and HIF1a-positive regions. Furthermore, NANOG and OCT4 expressions positively correlated with increased prostate tumor Gleason score. In primary glioma-derived CD133 negative cells, hypoxia was able to induce neurospheres and hESC markers. Together, these findings suggest that HIF targets may act as key inducers of a dynamic state of stemness in pathologic conditions. ©2011 AACR.
Gentile M.A.,Merck And Co. |
Nantermet P.V.,Merck And Co. |
Vogel R.L.,Merck And Co. |
Phillips R.,Rosetta Inpharmatics LLC |
And 6 more authors.
Journal of Molecular Endocrinology | Year: 2010
Androgens promote anabolism in the musculoskeletal system while generally repressing adiposity, leading to lean body composition. Circulating androgens decline with age, contributing to frailty, osteoporosis, and obesity; however, the mechanisms by which androgens modulate body composition are largely unknown. Here, we demonstrate that aged castrated rats develop increased fat mass, reduced muscle mass and strength, and lower bone mass. Treatment with testosterone or 5α-dihydrotestosterone (DHT) reverses the effects on muscle and adipose tissues while only aromatizable testosterone increased bone mass. During the first week, DHT transiently increased soleus muscle nuclear density and induced expression of IGF1 and its splice variant mechano growth factor (MGF) without early regulation of the myogenic factors MyoD, myogenin, monocyte nuclear factor, or myostatin. A genome-wide microarray screen was also performed to identify potential pro-myogenic genes that respond to androgen receptor activation in vivo within 24 h. Of 24 000 genes examined, 70 candidate genes were identified whose functions suggest initiation of remodeling and regeneration, including the type II muscle genes for myosin heavy chain type II and parvalbumin and the chemokine monocyte chemoattractant protein-1. Interestingly, Axin and Axin2, negative regulators of β-catenin, were repressed, indicating modulation of the β-catenin pathway. DHT increased total levels of β-catenin protein, which accumulated in nuclei in vivo. Likewise, treatment of C2C12 myoblasts with both IGF1Ea and MGF C-terminal peptide increased nuclear β-catenin in vitro. Thus, we propose that androgenic anabolism involves early downregulation of Axin and induction of IGF1, leading to nuclear accumulation of β-catenin, a pro-myogenic, anti-adipogenic stem cell regulatory factor. © 2010 Society for Endocrinology.
Lee S.-Y.,Fox Chase Cancer Center |
Coffey F.,Fox Chase Cancer Center |
Fahl S.P.,Fox Chase Cancer Center |
Peri S.,Fox Chase Cancer Center Philadelphia |
And 9 more authors.
Immunity | Year: 2014
Gradations in extracellular regulated kinase (ERK) signaling have been implicated in essentially every developmental checkpoint or differentiation process encountered by lymphocytes. Yet, despite intensive effort, the molecular basis by which differences in ERK activation specify alternative cell fates remains poorly understood. We report here that differential ERK signaling controls lymphoid-fate specification through an alternative mode of action. While ERK phosphorylates most substrates, such as RSK, by targeting them through its D-domain, this well-studied mode of ERK action was dispensable for development of γδ Tcells. Instead, development of γδ Tcells was dependent upon an alternative mode of action mediated by the DEF-binding pocket (DBP) of ERK. This domain enabled ERK to bind a distinct and select set of proteins required for specification of the γδ fate. These data provide the first invivo demonstration for the role of DBP-mediated interactions in orchestrating alternate ERK-dependent developmental outcomes. © 2014 Elsevier Inc.
PubMed | Rosetta Inpharmatics LLC
Type: | Journal: BMC genomics | Year: 2010
Identifying associations between genotypes and gene expression levels using microarrays has enabled systematic interrogation of regulatory variation underlying complex phenotypes. This approach has vast potential for functional characterization of disease states, but its prohibitive cost, given hundreds to thousands of individual samples from populations have to be genotyped and expression profiled, has limited its widespread application.Here we demonstrate that genomic regions with allele-specific expression (ASE) detected by sequencing cDNA are highly enriched for cis-acting expression quantitative trait loci (cis-eQTL) identified by profiling of 500 animals in parallel, with up to 90% agreement on the allele that is preferentially expressed. We also observed widespread noncoding and antisense ASE and identified several allele-specific alternative splicing variants.Monitoring ASE by sequencing cDNA from as little as one sample is a practical alternative to expression genetics for mapping cis-acting variation that regulates RNA transcription and processing.
PubMed | Rosetta Inpharmatics LLC
Type: Journal Article | Journal: PloS one | Year: 2011
In hepatocellular carcinoma (HCC) genes predictive of survival have been found in both adjacent normal (AN) and tumor (TU) tissues. The relationships between these two sets of predictive genes and the general process of tumorigenesis and disease progression remains unclear.Here we have investigated HCC tumorigenesis by comparing gene expression, DNA copy number variation and survival using 250 AN and TU samples representing, respectively, the pre-cancer state, and the result of tumorigenesis. Genes that participate in tumorigenesis were defined using a gene-gene correlation meta-analysis procedure that compared AN versus TU tissues. Genes predictive of survival in AN (AN-survival genes) were found to be enriched in the differential gene-gene correlation gene set indicating that they directly participate in the process of tumorigenesis. Additionally the AN-survival genes were mostly not predictive after tumorigenesis in TU tissue and this transition was associated with and could largely be explained by the effect of somatic DNA copy number variation (sCNV) in cis and in trans. The data was consistent with the variance of AN-survival genes being rate-limiting steps in tumorigenesis and this was confirmed using a treatment that promotes HCC tumorigenesis that selectively altered AN-survival genes and genes differentially correlated between AN and TU.This suggests that the process of tumor evolution involves rate-limiting steps related to the background from which the tumor evolved where these were frequently predictive of clinical outcome. Additionally treatments that alter the likelihood of tumorigenesis occurring may act by altering AN-survival genes, suggesting that the process can be manipulated. Further sCNV explains a substantial fraction of tumor specific expression and may therefore be a causal driver of tumor evolution in HCC and perhaps many solid tumor types.
PubMed | Rosetta Inpharmatics LLC
Type: Journal Article | Journal: Omics : a journal of integrative biology | Year: 2010
Copy number variation (CNV) is one of the most profound forms of somatic DNA changes that underlie most human cancers. However, the degree of complexity within and between DNA and mRNA variations in cancer cohorts has yet to be fully characterized. Here we characterized the connectivity of CNV/CNV and its contribution to transcriptome in human cancer cell lines. Strikingly, we found there is a significant nonrandom correlation of many unlinked DNA loci and also a significant association between CNV and mRNA expression in cis and in trans (called eCNV). Both distributions of DNA/DNA and DNA/mRNA associations exhibit a scale-free structure showing that, for DNA/DNA, a few loci correlate to many other loci, whereas most loci correlate to only a few loci; and for DNA/mRNA, certain chromosomal loci associate with many mRNAs and that many mRNAs are controlled by more than one locus. This suggests that a small number of DNA loci act as hubs in a hierarchical structure that is highly nonrandom in nature, and genes linking to these hot spots tend to be involved in similar biological functions. Derivation of highly connected structures suggests a process of undirected copy number changes followed by selection of those advantageous to tumor cells during tumorigenesis. Given that the cohort includes many tissue types, our observations may identify a common and important underlying structure present in human tumors.