Gene expression studies are used to help identify disease-associated genes, by comparing the levels of expressed transcripts between cases and controls, and to identify functional genetic variants known as expression quantitative loci (eQTLs). While many of these studies are performed in blood or lymphoblastoid cell lines due to tissue accessibility, the relevance of expression differences in tissues that are not the primary site of disease is unclear. Further, many eQTLs are tissue specific. Thus, there is a clear and compelling need to conduct gene expression studies in tissues that are specifically relevant to the disease of interest. One major technical concern about using autopsy-derived tissue is how representative it is of physiologic conditions, given the effect of postmortem interval on tissue degradation.
Postmortem cardiac tissue maintains gene expression profile even after late harvesting.
Specimen part, Disease, Cell line
View SamplesCaloric Restriction in Leptin Deficiency Worsens Myocardial Steatosis: Failure to Upregulate PPAR gamma and Thermogenic Glyecrolipid/Fatty Acid Cycling
Caloric restriction in leptin deficiency does not correct myocardial steatosis: failure to normalize PPAR{alpha}/PGC1{alpha} and thermogenic glycerolipid/fatty acid cycling.
Specimen part
View SamplesIntroduction: Mammalian target of rapamycin (mTOR) represents a key downstream intermediate for a myriad of oncogenic receptor tyrosine kinases. In the case of the insulin-like growth factor (IGF) pathway, the mTOR complex (mTORC1) mediates IGF-1 receptor (IGF-1R)-induced estrogen receptor alpha (ERa) phosphorylation/activation and leads to increased proliferation and growth in breast cancer cells. As a result, the prevalence of mTOR inhibitors combined with hormonal therapy has increased in recent years. Conversely, activated mTORC1 provides negative feedback regulation of IGF signaling via insulin receptor substrate (IRS)-1/2 serine phosphorylation and subsequent proteasomal degradation. Thus, the IGF pathway may provide escape (e.g. de novo or acquired resistance) from mTORC1 inhibitors. It is therefore plausible that combined inhibition of mTORC1 and IGF-1R for select subsets of ER-positive breast cancer patients presents as a viable therapeutic option. Methods: Using hormone-sensitive breast cancer cells stably transfected with the aromatase gene (MCF-7/AC-1), works presented herein describe the in vitro and in vivo antitumor efficacy of the following compounds: dalotuzumab (DALO; “MK-0646”; anti-IGF-1R antibody), ridaforolimus (RIDA; “MK-8669”; mTORC1 small molecule inhibitor) and letrozole (“LET”, aromatase inhibitor). Results: With the exception of MK-0646, all single agent and combination treatment arms effectively inhibited xenograft tumor growth, albeit to varying degrees. Correlative tissue analyses revealed MK-0646 alone and in combination with LET induced insulin receptor alpha A (InsR-A) isoform upregulation (both mRNA and protein expression), thereby further supporting a triple therapy approach. Conclusion: These data provide preclinical rationalization towards the combined triple therapy of LET plus MK-0646 plus MK-8669 as an efficacious anti-tumor strategy for ER-positive breast tumors. Overall design: 46 samples, 28 days post treatment
Ridaforolimus (MK-8669) synergizes with Dalotuzumab (MK-0646) in hormone-sensitive breast cancer.
Cell line, Treatment, Subject, Time
View SamplesEpithelial tumor cells (E) underwent EMT in vivo in FVB/N mice generating mesenchymal tumors. Mesenchymal cell lines (M1-M4) were each derived from a different mouse. This study compares gene expression between these two different tumor types.
Immune-induced epithelial to mesenchymal transition in vivo generates breast cancer stem cells.
No sample metadata fields
View SamplesThe primary goal of toxicology and safety testing is to identify agents that have the potential to cause adverse effects in humans. Unfortunately, many of these tests have not changed significantly in the past 30 years and most are inefficient, costly, and rely heavily on the use of animals. The rodent cancer bioassay is one of these safety tests and was originally established as a screen to identify potential carcinogens that would be further analyzed in human epidemiological studies. Today, the rodent cancer bioassay has evolved into the primary means to determine the carcinogenic potential of a chemical and generate quantitative information on dose-response behavior in chemical risk assessments. Due to the resource-intensive nature of these studies, each bioassay costs $2 to $4 million and takes over three years to complete. Over the past 30 years, only 1,468 chemicals have been tested in a rodent cancer bioassay. By comparison, approximately 9,000 chemicals are used by industry in quantities greater than 10,000 lbs and nearly 90,000 chemicals have been inventoried by the U.S. Environmental Protection Agency as part of the Toxic Substances Control Act. Given the disparity between the number of chemicals tested in a rodent cancer bioassay and the number of chemicals used by industry, a more efficient and economical system of identifying chemical carcinogens needs to be developed.
Application of genomic biomarkers to predict increased lung tumor incidence in 2-year rodent cancer bioassays.
Sex, Age, Subject
View SamplesHuman breast cancer cell line MCF-7 is usually sensitive to chemotherapy drug BMS-554417, an insulin receptor (IR) and insulin-like growth factor receptor (IGFR) inhibitor. However, through step-wise increase in BMS-554417 doses in culture media, we were able able to screen and select a single MCF-7 clone that is BMS-554417 resistant. It is cross resistant to BMS-536924. This new line of MCF-7 cells was named as MCF-7R4. The transcriptome profiling of both MCF-7 and MCF-7R4 was performed using Affymetrix HG-U133 plus2.0 GeneChip arrays.
Drug efflux by breast cancer resistance protein is a mechanism of resistance to the benzimidazole insulin-like growth factor receptor/insulin receptor inhibitor, BMS-536924.
Specimen part, Cell line
View SamplesThe pathophysiology of recurrent laryngeal nerve (RLN) transection injury is rare in that it is characteristically followed by a high degree of spontaneous reinnervation, with reinnervation of the laryngeal adductor complex (AC) preceding that of the abducting posterior cricoarytenoid (PCA) muscle. Here, we aim to elucidate the differentially expressed myogenic factors following RLN injury that may be at least partially responsible for the spontaneous reinnervation. F344 male rats underwent RLN injury or sham surgery (n=12). One week after RLN injury, larynges were harvested following euthanasia. mRNA was extracted from PCA and AC muscles bilaterally, and microarray analysis was performed using a full rat genome array. Microarray analysis of denervated AC and PCA muscles demonstrated dramatic differences in gene expression profiles, with 205 individual probes that were differentially expressed between the denervated AC and PCA muscles, and only 14 genes with similar expression patterns. The differential expression patterns of the AC and PCA suggest different mechanisms of reinnervation. The PCA showed the gene patterns of Wallerian degeneration, while the AC expressed the gene patterns of reinnervation by adjacent axonal sprouting. This finding may reveal important therapeutic targets applicable to RLN and other peripheral nerve injuries.
Microarray Analysis Gene Expression Profiles in Laryngeal Muscle After Recurrent Laryngeal Nerve Injury.
Sex, Specimen part, Treatment
View SamplesThe capacity of cancer cells to undergo epithelial mesenchymal trans-differentiation has been implicated as a factor driving metastasis, through the acquisition of enhanced migratory/invasive cell programs and the engagement of anti-apoptotic mechanisms promoting drug and radiation resistance. Our aim was to define molecular signaling changes associated with mesenchymal trans-differentiation in two KRas mutant NSCLC models. We focused on central transcription and epigenetic regulators predicted to be important for mesenchymal cell survival. Overall design: Haley, J.A., Haughney, E., Ullman, E., Bean, J., Haley, J.D.* and Fink, M.Y. (2014) 'Altered Transcriptional Control Networks with Trans-Differentiation of Isogenic Mutant KRas NSCLC Models' Front. Oncology, doi/10.3389/fonc.2014.00344.
Altered Transcriptional Control Networks with Trans-Differentiation of Isogenic Mutant-KRas NSCLC Models.
Treatment, Subject
View SamplesPolycomb repressive complex-2 (PRC2) is a group of proteins that play important role during development and in cell differentiation. PRC2 is a histone-modifying complex that catalyses methylation of lysine 27 of histone H3 (H3K27me3) at differentiation genes leading to their transcriptional repression. JARID2 is a co-factor of PRC2 and is important for targeting PRC2 to chromatin as well as modulating its activity. Here, we show that in many human cells, including human epidermal keratinocytes, JARID2 predominantly exists as a novel low molecular weight form, which lacks the N-terminal PRC2-interacting domain (?N-JARID2). We show that ?N-JARID2 is a cleaved product of full-length JARID2 spanning the C-terminal conserved region consisting of jumonji domains. JARID2 knockout in keratinocytes results in up-regulation of cell cycle genes and repression of many epidermal differentiation genes. Surprisingly, repression of epidermal differentiation genes in JARID2-null keratinocytes can be relieved by expression of ?N-JARID2 suggesting that this form promotes activation of these genes and has opposing function to that of PRC2 in regulation of differentiation. We propose that a switch from expression of full-length JARID2 to ?N-JARID2 is important for the up-regulation of genes during differentiation. Overall design: RNA-seq analysis of Wildtype and JARID2-null keratinocytes (HaCaTs) on day 0 and day 3 of calcium induced differentiation.
A novel form of JARID2 is required for differentiation in lineage-committed cells.
Specimen part, Cell line, Subject
View SamplesPurpose:Ovarian cancer has a high recurrence and mortality rate. A barrier to improved outcomes includes a lack of accurate models for preclinical testing of novel therapeutics.
Tumorgrafts as in vivo surrogates for women with ovarian cancer.
No sample metadata fields
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