We performed mRNA expression profiling of lung tumors from C/L858R, C/T790M, and C/L+T mice and from corresponding normal lung tissue.
Dual targeting of EGFR can overcome a major drug resistance mutation in mouse models of EGFR mutant lung cancer.
No sample metadata fields
View SamplesAlthough most of the oncogenic phenotypes of PTEN loss have been attributed to AKT activation, AKT alone is not sufficient to induce all of the biological activities associated with PTEN inactivation. We searched for additional PTEN-regulated pathways through gene set enrichment analysis (GSEA) and found that PTEN inactivation causes an enrichment of genes associated with JNK activation. Biochemically, PTEN-null cells exhibit higher JNK activity, and genetic studies demonstrate that JNK functions parallel to and independently of AKT. Furthermore, PTEN deficiency sensitizes cells to JNK inhibition. We also found that negative feedback regulation of PI3K was impaired in PTEN-null cells. These findings implicate JNK in PI3K-driven cancers and demonstrate the utility of GSEA to identify functional pathways using genetically defined systems.
Identification of the JNK signaling pathway as a functional target of the tumor suppressor PTEN.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
IDH1 mutation is sufficient to establish the glioma hypermethylator phenotype.
Specimen part
View SamplesGlioma CIMP (G-CIMP) is a powerful determinant of tumor pathogenicity but the molecular cause of G-CIMP is a fundamental question that is unresolved. Here, we show that mutation of a single gene, isocitrate dehydrogenase 1 (IDH1), directly causes the G-CIMP in gliomas by remodeling the methylome.
IDH1 mutation is sufficient to establish the glioma hypermethylator phenotype.
Specimen part
View SamplesWe used a mouse expressing three alleles 1) KitV558Delta/+ activating allele that develop GIST-like tumors in the cecum, 2) Etv1 flox/flox conditional knockout allele and 3) Rosa26-CreERT2 tamoxifen activated Cre allele. Mice were treated with either Tamoxifen (to delete Etv1) or corn oil (control). Cecal tumors were isolated for gene expression profiling by RNA-Seq. Overall design: Expression profile mouse cecal GIST tumor with or without Etv1 ablation was generated by RNA-Seq
Combined inhibition of MAP kinase and KIT signaling synergistically destabilizes ETV1 and suppresses GIST tumor growth.
No sample metadata fields
View SamplesExpression data from HEK293 cells expressing a doxcycline-inducible RANBP6 shRNA
EGFR feedback-inhibition by Ran-binding protein 6 is disrupted in cancer.
Treatment
View SamplesFluorine-18-fluoro-2-deoxy-D-glucose (FDG) is widely used as positron-emission-tomography (PET) radiotracer for the detection and staging of human cancer. Tumor uptake of FDG varies substantially between different cancer types and between patients with the same tumor type. The molecular basis for this heterogeneity is unknown. Using cancer cell lines and primary human tumors of distinct histologic origins, we here show that increased FDG uptake is universally associated with coordinate upregulation of genes within the glycolysis, pentose-phosphate, and other related metabolic pathways. In primary human breast cancers, this FDG signature shows significant overlap with established breast cancer signatures for the basal-like disease subtype and poor prognosis. FDG high breast cancer showed significantly more gene copy number alterations genome wide than FDG low cancers. About 50 % of primary breast cancers with high FDG uptake and FDG gene expression signature show DNA copy gain encompassing the c-myc gene locus and express gene sets regulated by the transcription factor MYC. Our data shows that FDG-PET marks a distinct subset of basal-like human breast cancer which is characterized by MYC and prognostically unfavorable gene expression signatures, suggesting that FDG-PET imaging may be useful to risk-stratify patients with locally advanced breast cancer.
18F-fluorodeoxy-glucose positron emission tomography marks MYC-overexpressing human basal-like breast cancers.
Specimen part, Cell line
View SamplesThe FAT1 gene was knocked down using 2 independent siRNAs, in immortalized human astrocytes and U87 and U251 glioma cell lines.
Recurrent somatic mutation of FAT1 in multiple human cancers leads to aberrant Wnt activation.
Cell line
View SamplesDrosophila males double transcription of their single X chromosome to equalize X-linked gene expression with females, which carry two X chromosomes. Increased transcription requires the Male-Specific Lethal (MSL) complex. One of the primary functions of the MSL complex is thought to be enrichment of H4Ac16 on the male X chromosome, a modification linked to elevated transcription. The roX1 and roX2 RNAs are essential but redundant components of the MSL complex. Simultaneous removal of both roX RNAs reduces MSL X-localization and leads to ectopic binding of these proteins at autosomal sites and to the chromocenter. Some H4Ac16 accumulates at these ectopic sites in roX1- roX2- males, suggesting the possibility of increased expression. The global effect of roX mutations on gene expression was measured by microarray analysis. We found that expression of the X chromosome was decreased by 26% in roX1- roX2- male larvae, supporting the involvement of roX RNAs in the up-regulation of X-linked genes. This finding is broadly comparable to reports of reduced X chromosome expression following msl2 RNAi knockdown in S2 cells. In spite of strong MSL binding and H4Ac16 accumulation at autosomal sites in roX1- roX2- males, enhanced gene expression could not be detected at these sites by microarray analysis or reverse northern blotting. Thus, failure to compensate X-linked genes, rather than inappropriate up-regulation of autosomal genes at ectopic sites of MSL binding, appears to cause male lethality upon loss of roX RNAs.
roX RNAs are required for increased expression of X-linked genes in Drosophila melanogaster males.
Sex
View SamplesMany cancers rely on glycolytic metabolism to fuel rapid proliferation. This has spurred interest in designing drugs that target tumor glycolysis such as AZD3965, a small molecule inhibitor of Monocarboxylate Transporter 1 (MCT1) currently undergoing Phase I evaluation for cancer treatment. Since MCT1 mediates proton-linked transport of monocarboxylates such as lactate and pyruvate across the plasma membrane (Halestrap and Meredith, 2004), AZD3965 is thought to block tumor growth through disruption of lactate transport and glycolysis. Here we show that MCT1 inhibition impairs proliferation of glycolytic breast cancer cells that express MCT4 via disruption of pyruvate rather than lactate export. We found that MCT1 expression is elevated in glycolytic breast tumors and cell lines as well as in malignant breast and lung tissues. High MCT1 expression predicts poor prognosis in breast and lung cancer patients. Stable knockdown and AZD3965-mediated inhibition of MCT1 promote oxidative metabolism. Acute inhibition of MCT1 reduces pyruvate export rate but does not consistently alter lactate transport or glycolytic flux in breast cancer cells that also express MCT4. Despite the lack of glycolysis impairment, MCT1 loss-of-function decreases breast cancer cell proliferation and blocks growth of mammary fat pad xenograft tumors. Our data suggest that MCT1 expression is elevated in glycolytic cancers to promote pyruvate export, which when inhibited enhances oxidative metabolism and reduces proliferation. This study presents an alternative molecular consequence of MCT1 inhibitors that further supports their use as anti-cancer therapeutics.
MCT1 Modulates Cancer Cell Pyruvate Export and Growth of Tumors that Co-express MCT1 and MCT4.
Cell line, Treatment
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