Human mononuclear cells were cultured in 2 phases. In the 1st phase the culture medium contained cyclosporine A the 2nd phase contained SCF and erythropoietin. Cells were collected at 3 stages of differentiation; on day 6, 10, 12 and represented early erythroblasts, medium stage and normoblasts.
Identification of gene networks associated with erythroid differentiation.
No sample metadata fields
View SamplesDuplication of chromosomal arm 20q occurs in prostate, cervical, colon, gastric, bladder, melanoma, pancreas and breast cancer, suggesting that 20q amplification may play a key causal role in tumorigenesis. According to an alternative view, chromosomal instabilities are mainly a common side effect of cancer progression. To test whether a specific genomic aberration might serve as a cancer initiating event, we established an in vitro system that models the evolutionary process of early stages of prostate tumor formation; normal prostate cells were immortalized and cultured for 650 days till several transformation hallmarks were observed. Gene expression patterns were measured and chromosomal aberrations were monitored by spectral karyotype analysis at different times. Several chromosomal aberrations, in particular duplication of chromosomal arm 20q, occurred early in the process and were fixed in the cell populations, while other aberrations became extinct shortly after their appearance. A wide range of bioinformatic tools, applied to our data and to data from several cancer databases, revealed that spontaneous 20q amplification can promote cancer initiation. Our computational model suggests that deregulation of some key pathways, such as MAPK, p53, cell cycle regulation and Polycomb group factors, in addition to activation of several genes like Myc, AML, B-Catenin and the ETS family transcription factors, are key steps in cancer development driven by 20q amplification. Finally we identified 13 cancer initiating genes, located on 20q13, which were significantly overexpressed in many tumors, with expression levels correlated with tumor grade and outcome; these probably play key roles in inducing malignancy via20q amplification.
Amplification of the 20q chromosomal arm occurs early in tumorigenic transformation and may initiate cancer.
Specimen part
View SamplesBackground: Personalized medicine is predicated on the notion that individual biochemical and genomic profiles are relatively constant in times of good health and to some extent predictive of disease or therapeutic response. We report a pilot study quantifying gene expression and methylation profile consistency over time, addressing the reasons for individual uniqueness, and its relation to N=1 phenotypes. Methods: Whole blood samples from 4 African American women, 4 Caucasian women, and 4 Caucasian men drawn from the Atlanta Center for Health Discovery and Well Being study at three successive 6-month intervals were profiled by RNASeq, miRNASeq, and Illumina Methyl-450 arrays. Standard regression approaches were used to evaluate the proportion of variance for each type of omic measure that is among individuals, and to quantify correlations among measures and with clinical attributes related to wellness. Results: Longitudinal omic profiles are in general highly consistent over time, with an average of 67% of the variance in transcript abundance, 42% of CpG methylation level (but 88% for the most differentiated CpG per gene), and 50% of miRNA abundance among individuals, which are all comparable to 74% of the variance among individuals for 74 clinical traits. One third of the variance can be attributed to differential blood cell type abundance, which is also fairly stable over time, and a lesser amount to eQTL effects, whereas seven conserved axes of covariance that capture diverse aspects of immune function explain over half of the variance. These axes also explain a considerable proportion of individually extreme transcript abundance, namely approximately 100 genes that are significantly up- or down-regulated in each person and are in some cases enriched for relevant gene activities that plausibly associate with clinical attributes. A similar fraction of genes have individually divergent methylation levels, but these do not overlap with the transcripts, and fewer than 20% of genes have significantly correlated methylation and gene expression. Conclusions: People express an “omic personality” consisting of peripheral blood transcriptional and epigenetic profiles that are constant over the course of a year and reflect various types of immune activity. Baseline genomic profiles can provide a window into the molecular basis of traits that might be useful for explaining medical conditions or guiding personalized health decisions. Overall design: Whole blood samples from 12 subjects drawn from the Atlanta Center for Health Discovery and Well Being study at three successive 6-month intervals were profiled by RNASeq, miRNASeq, and Illumina Methyl-450 arrays.
Omic personality: implications of stable transcript and methylation profiles for personalized medicine.
No sample metadata fields
View SamplesN6-methyladenosine (m6A) is the most ubiquitous mRNA base modification, but little is known about its precise location, temporal dynamics, and regulation. Here, we generated genomic maps of m6A sites in meiotic yeast transcripts at nearly single-nucleotide resolution, identifying 1,308 putatively methylated sites within 1,183 transcripts. We validated 8/8 methylation sites in different genes with direct genetic analysis, demonstrated that methylated sites are significantly conserved in a related species, and built a model that predicts methylated sites directly from sequence. Sites vary in their methylation profiles along a dense meiotic time-course, and are regulated both locally, via predictable methylatability of each site, and globally, through the core meiotic circuitry. The methyltransferase complex components localize to the yeast nucleolus, and this localization is essential for mRNA methylation. Our data illuminates a conserved, dynamically regulated methylation program in yeast meiosis, and provides an important resource for studying the function of this epitranscriptomic modification. Overall design: Examination of m6A methylation under various conditions
High-resolution mapping reveals a conserved, widespread, dynamic mRNA methylation program in yeast meiosis.
Cell line, Subject
View SamplesWe wanted to examine the effect of vitamin D3 and endogenous mutant p53 expressed in SKBR3 cells on gene expression paterns.
Modulation of the vitamin D3 response by cancer-associated mutant p53.
Specimen part, Cell line, Treatment
View SamplesThe ARV1-encoded protein mediates sterol transport from the endoplasmic reticulum (ER) to the plasma membrane. Yeast ARV1 mutants accumulate multiple lipids in the ER and are sensitive to pharmacological modulators of both sterol and sphingolipid metabolism. Using fluorescent and electron microscopy, we demonstrate sterol accumulation, subcellular membrane expansion, elevated lipid droplet formation and vacuolar fragmentation in ARV1 mutants. Motif-based regression analysis of ARV1 deletion transcription profiles indicates activation of Hac1p, an integral component of the UPR. Accordingly, we show constitutive splicing of HAC1 transcripts, induction of a UPR reporter and elevated expression of UPR targets in ARV1 mutants. IRE1, encoding the unfolded protein sensor in the ER lumen, exhibits a lethal genetic interaction with ARV1, indicating a viability requirement for the UPR in cells lacking ARV1. Surprisingly, ARV1 mutants expressing a variant of Ire1p defective in sensing unfolded proteins are viable. Moreover these strains also exhibit constitutive HAC1 splicing that interacts with DTT-mediated perturbation of protein folding. These data suggest a component of UPR induction in arv1? strains is distinct from protein misfolding. Decreased ARV1 expression in murine macrophages also results in UPR induction, particularly up-regulation of activating transcription factor-4, C/EBP homologous protein (CHOP) and apoptosis. Cholesterol loading or inhibition of cholesterol esterification further elevated CHOP expression in ARV1 knockdown cells. Thus, loss or down-regulation of ARV1 disturbs membrane and lipid homeostasis resulting in a disruption of ER integrity, one consequence of which is induction of the UPR.
Loss of subcellular lipid transport due to ARV1 deficiency disrupts organelle homeostasis and activates the unfolded protein response.
No sample metadata fields
View SamplesBackground. More than one million women in fertile age are infected with Trypanosoma cruzi worldwide. Anti-T.cruzi seropositivity in mothers has been associated with adverse pregnancy outcome but there is still a knowledge gap regarding this effect. Our aim was to compare the gene expression profile of term placental environment from T. cruzi seropositive (SP) and seronegative (SN) mothers. Methods. A RNA-Seq was performed in 9 pools of 2 different placental RNA samples each: 3 belonging to placentas from SN and 6 from SP. Each pool consisted of a binomial of a female/male newborn and a vaginal/caesarean delivery. None of the newborns resulted infected. Results. Only 42 genes showed a significant fold change between SP and SN groups. Among the down-regulated genes were KISS1 and CGB5. In the up-regulated genes group were: KIF12, HLA-G, PRG2, TAC3, FN1 and ATXN3L. To identify pathways significantly associated with maternal T. cruzi-infection, a gene-set association analysis was implemented. The placental environment transcriptomic profile of SP consisted of an enrichment in immunological genes sets (inflammatory response and lymphocytic activation were over-expressed) whereas numerous biosynthetic processes were down-regulated. Conclusions. It is worth noting that several differentially expressed genes in SP placentas code for proteins associated to preeclampsia and miscarriage. This first transcriptomics study in human term placental environment from non-infected deliveries shows a placental response that may affect the faetus while protecting it from the parasite infection; this host response could be responsible for the low rate of congenital transmission observed in human chronic Chagas disease. Background. More than one million women in fertile age are infected with Trypanosoma cruzi worldwide. Anti-T.cruzi seropositivity in mothers has been associated with adverse pregnancy outcome but there is still a knowledge gap regarding this effect. Our aim was to compare the gene expression profile of term placental environment from T. cruzi seropositive (SP) and seronegative (SN) mothers. Methods. A RNA-Seq was performed in 9 pools of 2 different placental RNA samples each: 3 belonging to placentas from SN and 6 from SP. Each pool consisted of a binomial of a female/male newborn and a vaginal/caesarean delivery. None of the newborns resulted infected. Results. Only 42 genes showed a significant fold change between SP and SN groups. Among the down-regulated genes were KISS1 and CGB5. In the up-regulated genes group were: KIF12, HLA-G, PRG2, TAC3, FN1 and ATXN3L. To identify pathways significantly associated with maternal T. cruzi-infection, a gene-set association analysis was implemented. The placental environment transcriptomic profile of SP consisted of an enrichment in immunological genes sets (inflammatory response and lymphocytic activation were over-expressed) whereas numerous biosynthetic processes were down-regulated. Conclusions. It is worth noting that several differentially expressed genes in SP placentas code for proteins associated to preeclampsia and miscarriage. This first transcriptomics study in human term placental environment from non-infected deliveries shows a placental response that may affect the faetus while protecting it from the parasite infection; this host response could be responsible for the low rate of congenital transmission observed in human chronic Chagas disease. Overall design: Serodiagnosis of pregnant women was done by means of conventional serological methods and carried out by the respective health centres based on routine assays. In maternal and umbilical cord blood samples T. cruzi presence was tested using multiplex Real Time PCR as previously described [6]. Maternal infection with other pathogens that produce congenital transmission and adverse pregnancy outcome were considered as exclusion criteria, as well as missing data or incorrect sampling. Fresh normal placentas were obtained after labour from vaginal or caesarean deliveries and placed within 24 hours at 4°C. Each placenta was dissected and the middle section [7] at 2 cm distance from the umbilical cord was isolated and placed into RNAlater solution (Applied Biosystems, Foster City, CA). Total RNA was extracted with TRIzol reagent (Invitrogen, Carlsbad, CA) and stored at -80°C until used. Transcriptomic studies. A RNA-Seq experiment was done in 9 pools of 2 different placental RNA samples each: 3 pools (C1, C2 and C3) belonging to placentas from seronegative mothers (SN) and 6 pools (TC4 to TC9) from seropositive mothers (SP). Each pool consisted of a binomial of a female/male newborn and a vaginal/caesarean delivery. The cDNA Libraries were prepared according to Illumina''s TruSeq Stranded Total RNA with Ribo-Zero Gold for Human and a Hiseq 2.500 Illumina platform with 100 bp paired-end reads was used for sequencing
Alterations in Placental Gene Expression of Pregnant Women with Chronic Chagas Disease.
Subject
View SamplesMaternal smoking has a severe negative effect on all stages of pregnancy that in consequence impairs fetal growth and development. Tobacco smoke-related defects are well established at the clinical level; however, little is known about molecular mechanisms underlying these pathological conditions. We thus employed a genomic approach to determine transcriptome alterations induced by maternal smoking in pregnancy. We assayed gene expression profiles in peripheral blood (M) leukocytes and placentas (PL) of pregnant smokers and those without significant exposure, and in cord blood (D) leukocytes of their babies. Comparative analyses defined significant deregulation of 193 genes in M cells, 329 genes in placentas, and 49 genes in D cells of smokers. These genes were mainly involved in xenobiotic metabolism, oxidative stress, inflammation, immunity, hematopoiesis, trophoblast differentiation, and vascularization. Functional annotation of the deregulated genes outlined processes and pathways affected by tobacco smoke. In smoker newborns, we identified several deregulated pathways associated with autoimmune diseases. The study demonstrates a limited ability of placenta to modulate toxic effects of maternal tobacco use at the gene expression level.
Transcriptome alterations in maternal and fetal cells induced by tobacco smoke.
Age, Specimen part, Subject
View SamplesPassive smoke intake by pregnant women may have detrimental effects such as spontaneous abortion, lower birth weight, stillbirth, and reduced infant lung function. To extend our knowledge on molecular effects of tobacco smoke exposure in pregnancy, we analyzed transcriptome alterations in passive smokers (PS) and compared them to those in active smokers (AS). Using Illumina Expression Beadchip with 24,526 transcript probes, gene expression patterns were assayed in placentas from PS (N=25) exposed to environmental tobacco smoke (ETS) throughout pregnancy and non-exposed (NS) counterparts (N=35), and in cord blood cells from their newborns. The ETS exposure was evaluated by questionnaire disclosure and cotinine measurement in maternal and cord bloods. A total of 196 genes were significantly deregulated in placentas of PS compared to NS. These genes were primary associated with extracellular matrix, apoptosis, blood clotting, response to stress, embryonic morphogenesis, and lipid metabolism. Cord blood of newborns of PS displayed differential expression of 116 genes encoding mainly neuronal factors, regulators of immunologic response, and protooncogenes. Gene ontology analyses highlighted some important biological processes that might be associated with placental insufficiency and fetal growth restriction in PS, such as fatty acid catabolism, coagulation, regulation of growth, and response to steroid hormone stimulus. The study demonstrates that even low dose exposure to ETS during pregnancy leads to the significant deregulation of transcriptional regulation in placental and fetal cells. The data suggest the effect of ETS on the fetus is primary indirect, mediated via deregulation of placental functions. Comparison of PS and AS indicated that ETS exposure and active smoking in pregnancy partly employ the same molecular mechanisms.
Deregulation of gene expression induced by environmental tobacco smoke exposure in pregnancy.
Age
View SamplesTanning is a skin protection mechanism against UV radiation. Pigment production initiates hours after exposure, and the mechanism controlling this delay was unknown. Here we reveal a skin UV-protection timer, governed by damped oscillatory dynamics of the melanocyte master regulator, MITF, which after UV exposure, synchronizes regulatory programs, first cell survival and later pigmentation. Remarkably, the same amount of UV dosage resulted in higher pigmentation of human skin when given every-other day compared to daily exposure. Daily UV exposure appears to perturb MITF dynamics, thus re-ordering the survival and pigmentation programs. This demonstrates that the skin is more sensitive to frequency than quantity of UV exposure. Mathematical modeling identified a double negative regulatory loop involving HIF1a and microRNA-148a that regulates MITF dynamics. Our study suggests evolutionary leverage of the UV-protection timer, as it evolved to induce maximum protection with minimum damage for the reduction of skin cancer risk.
UV-Protection Timer Controls Linkage between Stress and Pigmentation Skin Protection Systems.
Time
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