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SRP066956
Homo sapiens
22 Downloadable Samples
IlluminaHiSeq2500
Description
Although mechanisms of acquired resistance of EGFR mutant non-small cell lung cancers to EGFR inhibitors have been identified, little is known about how resistant clones evolve during drug therapy. Here, we observe that acquired resistance caused by the T790M gatekeeper mutation can occur either by selection of pre-existing T790M clones or via genetic evolution of initially T790M-negative drug tolerant cells. The path to resistance impacts the biology of the resistant clone, as those that evolved from drug tolerant cells had a diminished apoptotic response to third generation EGFR inhibitors that target T790M EGFR; treatment with navitoclax, an inhibitor of BCL-XL and BCL-2 restored sensitivity. We corroborated these findings using cultures derived directly from EGFR inhibitor-resistant patient tumors. These findings provide evidence that clinically relevant drug resistant cancer cells can both pre-exist and evolve from drug tolerant cells, and point to therapeutic opportunities to prevent or overcome resistance in the clinic. Overall design: Examination of mRNA levels of PC9 parental, drug-tolerant, PC9-GR2 and PC9-GR3 cells after treatment with vehicle, gefitinib or WZ4002 for 24 hours.
Publication Title
Tumor cells can follow distinct evolutionary paths to become resistant to epidermal growth factor receptor inhibition.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 27 Downloadable Samples
Illumina MouseWG-6 v2.0 expression beadchip
Description
TET-family enzymes convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) in DNA. Tet1 and Tet2 are Oct4-regulated enzymes that together sustain 5hmC in mouse embryonic stem (ES) cells. ES cells depleted of Tet1 by RNAi show diminished expression of the Nodal antagonist Lefty1, and display hyperactive Nodal signalling and skewed differentiation into the endoderm-mesoderm lineage in embryoid bodies in vitro. In Fgf4- and heparin-supplemented culture conditions that favor derivation of trophoblast stem (TS) cells, Tet1-depleted ES cells activate the trophoblast stem cell lineage determinant Elf5 and can colonize the placenta in mid-gestation embryo chimeras. Consistent with these findings, Tet1-depleted ES cells form aggressive hemorrhagic teratomas with increased endoderm, reduced neuroectoderm and ectopic appearance of trophoblastic giant cells. Thus Tet1 functions to regulate the lineage differentiation potential of ES cells. Here, we performed whole-genome transcriptome profiling of ES cells stably depleted of Tet1 by shRNA knockdown (Tet1-kd) cultured in either standard ES cell or in TS cell culture conditions. Gene expression changes in Tet1-kd ES cells were fairly modest compared to control (GFP-kd) cells, although gene ontology (GO) analysis of differentially expressed genes yielded many terms related to embryonic development and cell cycle regulation. In TS cell culture conditions, a core set of genes defining trophectodermal cell differentiation, including Cdx2, Eomes and Tead4, was enriched in Tet1-kd compared to GFP-kd cells.
Publication Title
Tet1 and Tet2 regulate 5-hydroxymethylcytosine production and cell lineage specification in mouse embryonic stem cells.
Sample Metadata Fields
Specimen part
View Samples- Caenorhabditis elegans
- 15 Downloadable Samples
- Illumina HiSeq 2000
Description
The difference in X chromosome copy number creates a potential difference in X chromosomal gene expression between males and females. In many animals, dosage compensation mechanisms equalize X chromosome expression between sexes. Yet, X chromosome is also enriched for sex-biased genes due to differences in the evolutionary history of the X and autosomes. The manner in which dosage compensation and sex-biased gene expression exist on the X chromosome remains an open question. Most studies compare gene expression between two sexes, which combines expression differences due to X chromosome number (dose) and sex. Here, we uncoupled the effects of sex and X dose in C. elegans and determined how each process affects expression of the X chromosome compared to autosomes. We found that in the soma, sex-biased expression on the X chromosome is almost entirely due to sex because the dosage compensation complex (DCC) effectively compensates for the X dose difference between sexes. In the germline where the DCC is not present, X chromosome copy number contributes to hermaphrodite-biased gene expression. These results suggest that X dose contributes to sex-biased gene expression based on the level of dosage compensation in different tissues and developmental stages. Overall design: RNA-Seq profiles of C. elegans XO hermaphrodite and XX male L3 larvae and adults
Publication Title
Untangling the Contributions of Sex-Specific Gene Regulation and X-Chromosome Dosage to Sex-Biased Gene Expression in Caenorhabditis elegans.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Mrhl is a non coding RNA identified from mouse chromosome 8. It is a 2.4kb poly adenylated, nuclear restricted RNA expressed in multiple tissues. The 2.4 kb RNA also undergoes a nuclear processing event mediated through Drosha that generates an 80nt intermediate RNA. This study was aimed at understanding the functiion of mrhl by silencing the mrhl RNA in the mouse spermatogonial cells using a pool of siRNAs targeted against the mrhl and analyse the global gene expression change using Affymetrix mouse expression array. The mRNAs that showed significant change in expression in mrhl siRNA treated cells against control were studied further for their biological significance with respect to mrhl silencing.
Publication Title
mrhl RNA, a long noncoding RNA, negatively regulates Wnt signaling through its protein partner Ddx5/p68 in mouse spermatogonial cells.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 103 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
We have developed a total RNA amplification and labeling strategy for use with Affymetrix GeneChips. Our protocol, which we denote BIIB, employs two rounds of linear T7 amplification followed by Klenow labeling to generate a biotinylated cDNA. In benchmarking studies using a titration of mouse universal total RNA, BIIB outperformed commercially available kits in terms of sensitivity, accuracy, and amplified target length, while providing equivalent results for technical reproducibility. BIIB maintained 50 and 44% present calls from 100 and 50 pg of total RNA, respectively. Inter- and intrasample precision studies indicated that BIIB produces an unbiased and complete expression profile within a range of 5 ng to 50 pg of starting total RNA. From a panel of spiked exogenous transcripts, we established the BIIB linear detection limit to be 20 absolute copies. Additionally, we demonstrate that BIIB is sensitive enough to detect the stochastic events inherent in a highly diluted sample. Using RNA isolated from whole tissues, we further validated BIIB accuracy and precision by comparison of 224 expression ratios generated by quantitative real-time PCR. The utility of our method is ultimately illustrated by the detection of biologically expected trends in a T cell/B cell titration of 100 primary cells flow sorted from a healthy mouse spleen.
Publication Title
Accurate and precise transcriptional profiles from 50 pg of total RNA or 100 flow-sorted primary lymphocytes.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 9 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
AEBP1 has been identified as a transcriptional repressor playing a
Publication Title
Identification of genomic targets of transcription factor AEBP1 and its role in survival of glioma cells.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
ASCL1 is known to act as transcriptional activator of notch signaling pathway. We have found that ASCL1 is over expressed in secondary glioblastoma.
Publication Title
System analysis identifies distinct and common functional networks governed by transcription factor ASCL1, in glioma and small cell lung cancer.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 6 Downloadable Samples
- Illumina MouseWG-6 v2.0 expression beadchip
Description
Women are born with millions of primordial follicles which gradually decrease with increasing age and this irreversible supply of follicles completely exhausts at menopause. The fertility capacity of women diminishes in parallel with aging. The mechanisms for reproductive aging are not fully understood. In our recent work we observed a decline in BRCA1 mediated DNA repair in aging rat primordial follicles. To further understand the age-related molecular changes, we performed microarray gene expression analysis using total RNA extracted from immature (1820 days) and aged (400450 days) rat primordial follicles. The results of current microarray study revealed that there were 1011 (>1.5 fold, p<0.05) genes differentially expressed between two groups in which 422 genes were up-regulated and 589 genes were down-regulated in aged rat primordial follicles compared to immature. The gene ontology and pathway analysis of differentially expressed genes revealed a critical biological function such as cell cycle, oocyte meiosis, chromosomal stability, transcriptional activity, DNA replication and DNA repair were affected by age and this considerable difference in gene expression profiles may have adverse influence on oocyte quality. Our data provide information on the processes that may contribute to aging and age-related decline in fertility.
Publication Title
Age-related changes in gene expression patterns of immature and aged rat primordial follicles.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Spermatogonial stem cells (SSCs) provide foundation for spermatogenesis by undergoing continuous self-renewal division. Previous studies have reported conflicting results on the role of the pituitary gland activity in SSC self-renewal. In this study, we analyzed the role of hormonal regulation of SSCs using Lhcgr (luteinizing hormone/choriogonadotropin receptor) knockout mice. Analysis of gene expression profiles showed that testes of Lhcgr-deficient mice exhibit significantly enhanced Wnt5a expression in Sertoli cells.
Publication Title
The Luteinizing Hormone-Testosterone Pathway Regulates Mouse Spermatogonial Stem Cell Self-Renewal by Suppressing WNT5A Expression in Sertoli Cells.
Sample Metadata Fields
Sex, Specimen part
View Samples- Oryza sativa indica group
- 18 Downloadable Samples
- Affymetrix Rice Genome Array (rice)
Description
Traditional rice varieties found in India have many desirable characteristics. Amongst them, their differential responses to abiotic and biotic stresses are of great agricultural importance. Drought or osmotic stress is one of the major abiotic stresses afflicting crop plants in India. Indigenous varieties like Dagad deshi have been found to be drought resistant and, thereby, are being studied in great detail by plant breeders and biotechnologists alike. In this study, we have analyzed the transciptomes of two contrasting cultivars, i.e. Dagad deshi (tolerant) and IR20 (susceptible), under control and stress conditions to elucidate the differences in their responses to drought stress using Affymetrix microarray platform.
Publication Title
Reference genes for accurate gene expression analyses across different tissues, developmental stages and genotypes in rice for drought tolerance.
Sample Metadata Fields
Specimen part, Time
View Samples