NHR-23, a conserved member of the nuclear receptor family of transcription factors, is required for normal development in C. elegans where it plays a critical role in growth and molting. In a search for NHR-23 dependent genes, we performed whole genome comparative expression microarrays on both control and nhr-23 inhibited synchronized larvae. Genes that decreased in response to nhr-23 RNAi included several collagen genes. Unexpectedly, several hedgehog-related genes were also down-regulated after nhr-23 RNAi. A homozygous nhr-23 deletion allele was used to confirm the RNAi knockdown phenotypes and the changes in gene expression. Our results indicate that NHR-23 is a critical coregulator of functionally linked genes involved in growth and molting and reveal evolutionary parallels among the ecdysozoa.
NHR-23 dependent collagen and hedgehog-related genes required for molting.
Specimen part
View SamplesOur previous study using nude rats revealed that the parental JDCaP xenografts predominantly expressed full-length androgen receptor (AR) whereas the relapsed JDCaP xenografts after castration acquired AR splice variants including AR-V7 and ARv567es. To understand molecular mechanisms underlying the acquisition of AR splice variants in the JDCaP model, we performed microarray analysis using RNA samples of the xenografts without castration (Parent), the relapsed xenografts overexpressing full-length AR and AR-V7 (ARhiV7hi), and the relapsed xenografts expressing ARv567es (ARv567es).
The RNA helicase DDX39B and its paralog DDX39A regulate androgen receptor splice variant AR-V7 generation.
Specimen part
View SamplesGlobal DNA hypomethylation and DNA hypermethylation of promoter regionsincluding tumor suppressor genesare frequently detected in human cancers. Although many studies have suggested a contribution to carcinogenesis, it is still unclear whether the aberrant DNA hypomethylation observed in tumors is a consequence or a cause of cancer. We found that overexpression of Stella (also known as PGC7, Dppa3), a maternal factor required for the maintenance of DNA methylation in early embryos, induced global DNA hypomethylation and transformation in NIH3T3 cells. This hypomethylation was due to the binding of Stella to Np95 (also known as Uhrf1, ICBP90) and the subsequent impairment of Dnmt1 localization. In addition, enforced expression of Stella enhanced the metastatic ability of B16 melanoma cells through the induction of metastasis-related genes by inducing DNA hypomethylation of their promoter regions. Such DNA hypomethylation itself causes cellular transformation and metastatic ability. These data provide new insight into the function of global DNA hypomethylation in carcinogenesis.
Global DNA hypomethylation coupled to cellular transformation and metastatic ability.
Cell line
View SamplesThe post-transcriptional control of mRNA stability plays a critical role in numerous biological functions, including the immune response, cell cycle regulation and DNA damage response. HNRNPA0, which encodes an RNA-binding protein shown to regulate transcript stability via binding to the AU-rich elements (AREs) of mRNAs, is located within the commonly deleted segment of 5q31.2 in therapy-related myeloid neoplasms (t-MNs) with a del(5q). We hypothesized that loss of HNRNPA0 leads to alterations in hematopoietic differentiation due to changes in the expression of its target AU-rich transcripts. Using RNAi interference to model Hnrnpa0 loss in primary murine cells and an experimental cell system, we found that reduced Hnrnpa0 expression leads to a shift from monocytic towards granulocytic differentiation. Microarray-based global expression profiling revealed that Hnrnpa0 knockdown disproportionally impacts ARE-containing transcripts and alters expression of myeloid specification genes. The biological importance of ARE-containing genes in myeloid neoplasms is further supported by changes in gene expression of ARE-mRNAs in t-MN del(5q) patients, predicted by pathway analysis to activate tumor growth. Together, our findings suggest that alterations in ARE-containing genes can positively regulate the cellular proliferation of del(5q) cells and implicate haploinsufficiency of HNRNPA0 as one of the key initiation mutations in the pathogenesis of t-MN.
Knockdown of Hnrnpa0, a del(5q) gene, alters myeloid cell fate in murine cells through regulation of AU-rich transcripts.
Specimen part, Disease, Disease stage
View SamplesAtrial specific knockout of Nkx2-5 results in hyperplastic atria with ASD and conduction defects. To examine how Nkx2-5 regulates cardiac proliferation at late gestational stages, RNA-seq was performed. Overall design: Examination of expression profile of 2 Nkx2-5-null atria and 3 controls
Nkx2-5 suppresses the proliferation of atrial myocytes and conduction system.
No sample metadata fields
View SamplesContemporary treatment of pediatric acute myeloid leukemia (AML) requires the assignment of patients to specific risk groups. To explore whether expression profiling of leukemic blasts could accurately distinguish between the known risk groups of AML, we analyzed 130 pediatric and 20 adult AML diagnostic bone marrow or peripheral blood samples using the Affymetrix U133A microarray. Class discriminating genes were identified for each of the major prognostic subtypes of pediatric AML, including t(15;17)[PML-RARalpha], t(8;21)[AML1-ETO], inv(16) [CBFbeta-MYH11], MLL chimeric fusion genes, and cases classified as FAB-M7. When subsets of these genes were used in supervised learning algorithms, an overall classification accuracy of more than 93% was achieved. Moreover, we were able to use the expression signatures generated from the pediatric samples to accurately classify adult de novo AMLs with the same genetic lesions. The class discriminating genes also provided novel insights into the molecular pathobiology of these leukemias. Finally, using a combined pediatric data set of 130 AMLs and 137 acute lymphoblastic leukemias, we identified an expression signature for cases with MLL chimeric fusion genes irrespective of lineage. Surprisingly, AMLs containing partial tandem duplications of MLL failed to cluster with MLL chimeric fusion gene cases, suggesting a significant difference in their underlying mechanism of transformation. All the gene expression arrays are available through http://www.stjuderesearch.org/site/data/AML1/ in the original study (PMID:15226186). To study the RAS gene expression in the human AML patients, a total of 104 AML cases with known KRAS and NRAS status (including 72 gene expression arrays in the original study and 32 additional arrays acquired later on), as well as 4 CD34+ normal bone marrow cases deposited in GEO GSE33315, were including in this depository.
Dominant role of oncogene dosage and absence of tumor suppressor activity in Nras-driven hematopoietic transformation.
Disease, Disease stage
View SamplesC-C chemokine ligand 2 (CCL2) plays pivotal roles in tumor formation, progression, and metastasis. Although CCL2 expression has been found to be dependent on the nuclear factor (NF)B signaling pathway, the regulation of CCL2 production in tumor cells has remained unclear. We have identified a noncanonical pathway for regulation of CCL2 production that is mediated by mammalian target of rapamycin complex 1 (mTORC1) but independent of NF-B. Multiple phosphoproteomics approaches identified the transcription factor forkhead box K1 (FOXK1) as a downstream target of mTORC1. Activation of mTORC1 induces dephosphorylation of FOXK1 resulting in transactivation of the CCL2 gene. Inhibition of the mTORC1-FOXK1 axis attenuated insulin-induced CCL2 production as well as the accumulation of tumor-associated monocytes-macrophages and tumor progression in mice. Our results suggest that FOXK1 directly links mTORC1 signaling and CCL2 expression in a manner independent of NF-B, and that CCL2 produced by this pathway contributes to tumor progression.
Noncanonical Pathway for Regulation of CCL2 Expression by an mTORC1-FOXK1 Axis Promotes Recruitment of Tumor-Associated Macrophages.
Cell line
View SamplesC-C chemokine ligand 2 (CCL2) plays pivotal roles in tumor formation, progression, and metastasis. Although CCL2 expression has been found to be dependent on the nuclear factor (NF)B signaling pathway, the regulation of CCL2 production in tumor cells has remained unclear. We have identified a noncanonical pathway for regulation of CCL2 production that is mediated by mammalian target of rapamycin complex 1 (mTORC1) but independent of NF-B. Multiple phosphoproteomics approaches identified the transcription factor forkhead box K1 (FOXK1) as a downstream target of mTORC1. Activation of mTORC1 induces dephosphorylation of FOXK1 resulting in transactivation of the CCL2 gene. Inhibition of the mTORC1-FOXK1 axis attenuated insulin-induced CCL2 production as well as the accumulation of tumor-associated monocytes-macrophages and tumor progression in mice. Our results suggest that FOXK1 directly links mTORC1 signaling and CCL2 expression in a manner independent of NF-B, and that CCL2 produced by this pathway contributes to tumor progression.
Noncanonical Pathway for Regulation of CCL2 Expression by an mTORC1-FOXK1 Axis Promotes Recruitment of Tumor-Associated Macrophages.
Cell line
View SamplesC-C chemokine ligand 2 (CCL2) plays pivotal roles in tumor formation, progression, and metastasis. Although CCL2 expression has been found to be dependent on the nuclear factor (NF)B signaling pathway, the regulation of CCL2 production in tumor cells has remained unclear. We have identified a noncanonical pathway for regulation of CCL2 production that is mediated by mammalian target of rapamycin complex 1 (mTORC1) but independent of NF-B. Multiple phosphoproteomics approaches identified the transcription factor forkhead box K1 (FOXK1) as a downstream target of mTORC1. Activation of mTORC1 induces dephosphorylation of FOXK1 resulting in transactivation of the CCL2 gene. Inhibition of the mTORC1-FOXK1 axis attenuated insulin-induced CCL2 production as well as the accumulation of tumor-associated monocytes-macrophages and tumor progression in mice. Our results suggest that FOXK1 directly links mTORC1 signaling and CCL2 expression in a manner independent of NF-B, and that CCL2 produced by this pathway contributes to tumor progression.
Noncanonical Pathway for Regulation of CCL2 Expression by an mTORC1-FOXK1 Axis Promotes Recruitment of Tumor-Associated Macrophages.
Cell line
View SamplesPoorly differentiated type synovial sarcoma (PDSS) is a variant of synovial sarcoma characterized by predominantly round or short-spindled cells. Although accumulating evidence from clinicopathological studies suggests a strong association between this variant of synovial sarcoma and poor prognosis, little has been reported on the molecular basis of PDSS. To gain insight into the mechanism(s) that underlie the emergence of PDSS, we analyzed the gene expression profiles of 34 synovial sarcoma clinical samples, including 5 cases of PDSS, using an oligonucleotide microarray. In an unsupervised analysis, the 34 samples fell into 3 groups that correlated highly with histological subtype, namely, monophasic, biphasic, and poorly differentiated types. PDSS was characterized by down-regulation of genes associated with neuronal and skeletal development and cell adhesion, and up-regulation of genes on a specific chromosomal locus, 8q21.11. This locus-specific transcriptional activation in PDSS was confirmed by reverse transcriptase (RT)-PCR analysis of 9 additional synovial sarcoma samples. Our results indicate that PDSS tumors constitute a distinct genetic group based on expression profiles.
Gene expression profiling of synovial sarcoma: distinct signature of poorly differentiated type.
Sex, Specimen part
View Samples