C-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 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 SamplesIt is well-known that indomethacin (the cyclooxygenase 1 & 2 inhibitor) and RU486 (or mifepristone, the progesterone receptor antagonist) block follicular rupture in rats. To characterize genetic alterations in unruptured follicles, gene expression profiles in ovarian follicle were analyzed in indomethacin- and RU486-treated female Sprague-Dawley rats. Ovaries are collected at 22:00 on the proestrus day and 10:00 on the following estrus day after a single dose of indomethacin and RU486. Histopathologically, changes depicting responses to LH surge were observed in ovaries, uteri and vagina. Total RNA was extracted from pre-ovulatory follicles or unruptured follicles collected by laser microdissection and analyzed by GeneChip. Among genes showing statistically significant changes compared to control groups, following changes were considered relevant to induction of unruptured follicles. In indomethacin-treated rats, Wnt4 was down-regulated, suggesting effect on tissue integrity and steroid genesis. In RU486-treated rats, Adamts1, Adamts9, Edn2, Ednra, Lyve1, Plat, and Pparg were down-regulated. These changes suggest effects on proteolysis for extracellular matrix or surrounding tissue (Adamts1 & 9, and Plat), constriction of smooth muscle surrounding follicles (Edn2, Ednra, and Pparg), follicular fluid (Lyve1), and angiogenesis (Pparg). Down-regulation of angiogenesis related genes (Angpt2, Hmox1, and Vegfa) was observed in both treatment groups. Here, we clarify genetic alterations induced by the inhibition of cyclooxygenase or progesterone receptor.
Altered gene expression profile in ovarian follicle in rats treated with indomethacin and RU486.
Specimen part, Treatment
View SamplesMetabolism is tightly coupled with the process of aging, and tumorigenesis. However, the mechanisms regulating metabolic properties in different contexts remain unclear. Cellular senescence is widely recognized as an important tumor suppressor function and accompanies metabolic remodeling characterized by increased mitochondrial oxidative phosphorylation (OXPHOS). Here we showed retinoblastoma (RB) is required for the increased OXPHOS in oncogene-induced senescent (OIS) cells. Combined metabolic and gene expression profiling revealed that RB mediated activation of the glycolytic pathway in OIS cells, causing upregulation of several glycolytic genes and concomitant increases in the levels of associated metabolites in the glycolytic pathway. Knockdown of these genes by small interfering RNAs (siRNAs) resulted in decreased mitochondrial respiration, suggesting that RB-mediated glycolytic gene activation promotes metabolic flux into the OXPHOS pathway. These results suggest that coordinate transcriptional activation of metabolic genes by RB enables OIS cells to maintain metabolically bivalent states that both glycolysis and OXPHOS are highly active. Collectively, our findings demonstrated a previously unrecognized function of RB in OIS cells.
Retinoblastoma protein promotes oxidative phosphorylation through upregulation of glycolytic genes in oncogene-induced senescent cells.
Cell line, Treatment
View SamplesBy transcriptome analysis of IMR-90 human fibroblasts following oncogene-induced senescence (OIS) and replicative senescence (RS), we identified commonly regulated genes in both conditions.
The SETD8/PR-Set7 Methyltransferase Functions as a Barrier to Prevent Senescence-Associated Metabolic Remodeling.
Cell line, Treatment
View SamplesCellular senescence is an ireversible growth arrest with alterd metabolic potentials including DNA, RNA and protein dynamics. We found that loss of the SETD8/PR-Set7 methyltransferase, which catalyzes mono-methylation of histone H4 at lysine 20 (H4K20me1), induces senescence in human fibroblasts. To investigate the role of SETD8 in cellular senescence, we performed a microarray-based transcriptomic analysis in SETD8-knockdown cells. Our results demonstrate that SETD8 links the epigenomic gene regulation to senescence-associated metabolic remodeling.
The SETD8/PR-Set7 Methyltransferase Functions as a Barrier to Prevent Senescence-Associated Metabolic Remodeling.
Cell line
View SamplesThe identification of a marker that is expressed in the conjunctival epithelium but not in the corneal epithelium has been a growing need. A more specific marker of limbal and conjunctival epithelia would be necessary to detect non-corneal epithelial cells on the corneal surface. To search for conjunctival specific marker(s), we first performed preferential gene profiling in the conjunctiva in direct comparison to that in the cornea using microarray technique.
Keratin 13 is a more specific marker of conjunctival epithelium than keratin 19.
Specimen part
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