PURPOSE: Previous mouse studies using corn oil (-6) as the dietary fat source suggest that decreasing dietary fat content can slow prostate cancer (PCa) growth. However, other studies, in which the diet was composed around saturated fat, showed no difference in outcomes between high-fat and low-fat diets. The relative effects of other fats, such as fish oil and olive oil, also remain unexplored. To our knowledge, no trial has yet compared the effect of various fats on prostate cancer progression. Therefore, we sought to systematically study the effect of fish oil, olive oil, corn oil, and saturated fat on prostate cancer progression. METHODS: A total of 96 male SCID mice were injected with LAPC-4 human PCa cells. Two weeks following injection, mice were singly-housed and randomized to either a fish oil, olive oil, corn oil, or saturated fat based diet. Animals were euthanized when tumors reached 1,000 mm3. Serum was collected at sacrifice and assayed for PSA, insulin, IGF-1, IGFBP-3, and PGE-2 levels. Tumors were also assayed for PGE-2, and COX-2 levels, and gene array analysis was performed. RESULTS: Mice weights and tumor volumes were equivalent across groups at randomization. Overall, fish-oil consumption was associated with improved survival, relative to all other dietary groups (Log-rank, all p<0.05). We did not detect any significant difference in serum PSA, insulin, IGF-1, IGFBP-3, and PGE-2 levels. Glucose at the time of sacrifice was statistically different between groups, with the fish-oil fed mice having the highest levels of serum glucose (Kruskal-Wallis, p=0.03).
Fish oil slows prostate cancer xenograft growth relative to other dietary fats and is associated with decreased mitochondrial and insulin pathway gene expression.
Specimen part
View SamplesWe evaluated changes in mRNA stability and transcription using 4sU metabolic pulse labeling across a four hour time course following activation of Jurkat T cells with PMA and PHA Overall design: Measurement of total mRNA (T) and 4sU labeled mRNA (IP) in three biological replicates at five time points: prior to activation (U) and the first four hours after activation (1-4)
Functional coordination and HuR-mediated regulation of mRNA stability during T cell activation.
No sample metadata fields
View SamplesBesides being building blocks for protein synthesis, amino acids serve a wide variety of cellular functions, including acting as metabolic intermediates for ATP generation and for redox homeostasis. Upon amino acid deprivation, free uncharged tRNAs trigger GCN2-ATF4 to mediate the well-characterized transcriptional amino acid response (AAR). However, it is not clear whether the deprivation of different individual amino acids triggers identical or distinct AARs. Here, we characterized the global transcriptional response upon deprivation of one amino acid at a time. With the exception of glycine, which was not required for the proliferation of MCF7 cells, we found that the deprivation of most amino acids triggered a shared transcriptional response that included the activation of ATF4, p53 and TXNIP. However, there was also significant heterogeneity among different individual AARs. The most dramatic transcriptional response was triggered by methionine deprivation, which activated an extensive and unique response in different cell types. We uncovered that the specific methionine-deprived transcriptional response required creatine biosynthesis. This dependency on creatine biosynthesis was caused by the consumption of S-Adenosyl-L-methionine (SAM) during creatine biosynthesis that helps to deplete SAM under methionine deprivation and reduces histone methylations. As such, the simultaneous deprivation of methionine and sources of creatine biosynthesis (either arginine or glycine) abolished the reduction of histone methylation and the methionine-specific transcriptional response. Arginine-derived ornithine was also required for the complete induction of the methionine-deprived specific gene response. Collectively, our data identify a previously unknown set of heterogeneous amino acid responses and reveal a distinct methionine-deprived transcriptional response that results from the crosstalk of arginine, glycine and methionine metabolism via arginine/glycine-dependent creatine biosynthesis.
Comprehensive profiling of amino acid response uncovers unique methionine-deprived response dependent on intact creatine biosynthesis.
Cell line, Treatment, Time
View SamplesTwo phosphorylation states of RNAPII in HeLa cells
Genomic mapping of RNA polymerase II reveals sites of co-transcriptional regulation in human cells.
No sample metadata fields
View SamplesAltered metabolism is an important part of malignant transformation of tumor cells. Oncogenic transformation may reprogram tumor metabolism and render tumor cells addicted to extracellular nutrients. Such nutrient addictions associated with oncogenic mutations may offer therapeutic opportunities; however, it remains difficult to predict these nutrient addictions. Here, we performed a nutrigenetic screen to determine the phenotypes of isogenic pairs of clear-cell renal cancer cells (ccRCC) with or without VHL upon the deprivation of individual amino acids. We identified that cystine deprivation triggered rapid programmed necrosis in VHL-deficient RCC, but not in their VHL-restored counterparts. Similar cystine addiction was also observed in VHL-deficient primary RCC tumors cells. Blockage of cystine uptake significantly delayed xenograft growth of ccRCC. Importantly, cystine deprivation triggered similar metabolic changes regardless of VHL status. Therefore, metabolic differences due to cystine deprivation are not different enough to readily explain the distinct fate of life vs. death in VHL-deficient and restored cell.. Instead, we found that increased levels of TNF associated with VHL loss in the VHL-deficient RCC force them to rely on intact RIPK1 to inhibit apoptosis. However, this pre-existing elevated TNF in the VHL-deficient ccRCC renders these cells susceptible to the necrosis signaling triggered by cystine deprivation. In addition, we identified that cystine-deprived necrosis in VHL-deficient RCC depends on reciprocal amplification of the Src-p38-Noxa signaling and TNF-RIP1/3-MLKL necrosis pathways that culminate in MLKL oligomerization and programmed necrosis. Together, our data reveal that the contextual cystine-addictions in VHL-deficient ccRCC is dependent on activating pre-existing oncogenic pathways to trigger programmed necrosis.
Cystine Deprivation Triggers Programmed Necrosis in VHL-Deficient Renal Cell Carcinomas.
Cell line
View SamplesIn order to propagate a solid tumor, cancer cells must adapt to and survive under various tumor microenvironment (TME) stresses, such as hypoxia or lactic acidosis. To systematically identify genes that modulate cancer cell survival under stresses, we performed genome-wide shRNA screens under hypoxia or lactic acidosis. We discovered that genetic depletion of acetyl-CoA carboxylase (ACACA or ACC1) or ATP citrate lyase (ACLY) protected cancer cells from hypoxia-induced apoptosis. Additionally, loss of ACLY or ACC1 reduced levels and activities of the oncogenic transcription factor ETV4. Silencing ETV4 also protected cells from hypoxia-induced apoptosis and led to remarkably similar transcriptional responses as with silenced ACLY or ACC1, including an anti-apoptotic program. Metabolomic analysis found that while -ketoglutarate levels decrease under hypoxia in control cells, -ketoglutarate is paradoxically increased by hypoxia when ACC1 or ACLY are depleted. Supplementation with -ketoglutarate rescued the hypoxia-induced apoptosis and recapitulated the decreased expression and activity of ETV4 via an epigenetic mechanism. Therefore, ACC1 and ACLY regulate the levels of ETV4 under hypoxia via increased -ketoglutarate. These results reveal that ACC1/ACLY- -ketoglutarate-ETV4 is a novel means by which metabolic states regulate transcriptional output for life vs. death decisions under hypoxia. Since many lipogenic inhibitors are under investigation as cancer therapeutics, our findings suggest that the use of these inhibitors will need to be carefully considered with respect to oncogenic drivers, tumor hypoxia, progression and dormancy. More broadly, our screen provides a framework for studying additional tumor cell stress-adaption mechanisms in the future.
ACLY and ACC1 Regulate Hypoxia-Induced Apoptosis by Modulating ETV4 via α-ketoglutarate.
Specimen part, Cell line
View SamplesTranscriptional changes were analyzed in two colorectal cancer, two pancreatic cancer, and one small cell lung cancer cell line following treatment with the BET inhibitor GSK525762 and/or the MEK inhibitor trametinib using Affymetrix Human Genome U133 Plus 2.0 Arrays.
MEK inhibitors overcome resistance to BET inhibition across a number of solid and hematologic cancers.
Cell line, Treatment, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrative regulatory mapping indicates that the RNA-binding protein HuR couples pre-mRNA processing and mRNA stability.
Specimen part
View SamplesIntegrative regulatory mapping indicates that the RNA-binding protein HuR (ELAVL1) couples pre-mRNA processing and mRNA stability
Integrative regulatory mapping indicates that the RNA-binding protein HuR couples pre-mRNA processing and mRNA stability.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Dominant negative PPARγ promotes atherosclerosis, vascular dysfunction, and hypertension through distinct effects in endothelium and vascular muscle.
Specimen part
View Samples