Similar Datasets
Project description:Glioblastoma (GBM) stem cells (GSCs) reside in both hypoxic and vascular microenvironments within tumors. The molecular mechanisms that allow GSCs to occupy such contrasting niches are not understood. We used patient-derived GBM cultures to identify GSC subtypes with differential activation of Notch signaling, which co-exist in tumors but occupy distinct niches and match their metabolism accordingly. Multipotent GSCs with Notch pathway activation reside in perivascular niches, and are unable to entrain anaerobic glycolysis during hypoxia. In contrast, most CD133-expressing GSCs do not depend on canonical Notch signaling, populate tumors regardless of local vascularity and selectively utilize anaerobic glycolysis to expand in hypoxia. Ectopic activation of Notch signaling in CD133-expressing GSCs is sufficient to suppress anaerobic glycolysis and resistance to hypoxia. These findings demonstrate a novel role for Notch signaling in regulating GSC metabolism and suggest intratumoral GSC heterogeneity ensures metabolic adaptations to support tumor growth in diverse tumor microenvironments.
| S-EPMC5630302 | biostudies-literature
Project description:Interventions: Case vs control:No
Primary outcome(s): High-throughput sequencing
Study Design: Case-Control study
| 2676067 | ecrin-mdr-crc
Project description:To investigate the changes in global transcriptome expression of HSCs following infection, we performed high-throughput sequencing of Poly A+ RNA (RNA-Seq) from purified HSCs (SP KSL CD150+) isolated from naive or Mycobacterium avium infected mice
2017-01-04 | GSE89364 | GEO
Project description:To investigate the global transcriptome expression in Dnmt3ab dKO HSCs, we performed high-throughput sequencing of Poly A+ RNA (RNA-Seq) from purified HSCs (SP-KSL-CD150+). With biological duplicates, more than 200 million reads in total for each genotype of HSC were obtained. Mouse hematopoietic stem cell mRNA profiles of Dnmt3ab Dko HSCs, generated by deep sequencing, in duplicate, using Illumina Hiseq 2000
2014-08-19 | E-GEOD-50775 | biostudies-arrayexpress
Project description:To investigate the global transcriptome expression in Dnmt3ab dKO HSCs, we performed high-throughput sequencing of Poly A+ RNA (RNA-Seq) from purified HSCs (SP-KSL-CD150+). With biological duplicates, more than 200 million reads in total for each genotype of HSC were obtained.
2014-08-19 | GSE50775 | GEO
Project description:Both chromatin accessibility and histone modifications are known to influence transcriptional regulation. We investigated the differences of chromatin accessibility among GSCs, NSTCs and NPC using ATAC-seq (assay for transposase-accessible chromatin with high throughput sequencing).
2022-08-28 | GSE211724 | GEO
Project description:BACKGROUND:The phosphatase chronophin (CIN/PDXP) has been shown to be an important regulator of glioma cell migration and invasion. It has two known substrates: p-Ser3-cofilin, the phosphorylated form of the actin binding protein cofilin, and pyridoxal 5'-phosphate, the active form of vitamin B6. Phosphoregulation of cofilin, among other functions, plays an important role in cell migration, whereas active vitamin B6 is a cofactor for more than one hundred enzymatic reactions. The role of CIN has yet only been examined in glioblastoma cell line models derived under serum culture conditions. RESULTS:We found that CIN is highly expressed in cells cultured under non-adherent, serum-free conditions that are thought to better mimic the in vivo situation. Furthermore, the substrates of CIN, p-Ser3-cofilin and active vitamin B6, were significantly reduced as compared to cell lines cultured in serum-containing medium. To further examine its molecular role we stably knocked down the CIN protein with two different shRNA hairpins in the glioblastoma cell lines NCH421k and NCH644. Both cell lines did not show any significant alterations in proliferation but expression of differentiation markers (such as GFAP or TUBB3) was increased in the knockdown cell lines. In addition, colony formation was significantly impaired in NCH644. Of note, in both cell lines CIN knockdown increased active vitamin B6 levels with vitamin B6 being known to be important for S-adenosylmethionine biosynthesis. Nevertheless, global histone and DNA methylation remained unaltered as was chemoresistance towards temozolomide. To further elucidate the role of phosphocofilin in glioblastoma cells we applied inhibitors for ROCK1/2 and LIMK1/2 to our model. LIMK- and ROCK-inhibitor treatment alone was not toxic for glioblastoma cells. However, it had profound, but antagonistic effects in NCH421k and NCH644 under chemotherapy. CONCLUSION:In non-adherent glioblastoma cell lines cultured in serum-free medium, chronophin knockdown induces phenotypic changes, e.g. in colony formation and transcription, but these are highly dependent on the cellular background. The same is true for phenotypes observed after treatment with inhibitors for kinases regulating cofilin phosphorylation (ROCKs and LIMKs). Targeting the cofilin phosphorylation pathway might therefore not be a straightforward therapeutic option in glioblastoma.
| S-EPMC5934884 | biostudies-literature
Project description:Interventions: left hemicolectomy:None;right hemicolectomy:None;sigmoid resection:None;radical rectal cancer:None;low rectal resection with prophylactic ileostomy:None
Primary outcome(s): Fecal high-throughput sequencing;Fecal Metabolomics;immunomics
Study Design: Factorial
| 85716 | ecrin-mdr-crc
Project description:Metabolic dysregulation promotes cancer growth through not only energy production, but also epigenetic reprogramming. Here, we report that a critical node in methyl donor metabolism, nicotinamide N-methyltransferase (NNMT), ranked among the most consistently overexpressed metabolism genes in glioblastoma relative to normal brain. NNMT was preferentially expressed by mesenchymal glioblastoma stem cells (GSCs). NNMT depletes S-adenosyl methionine (SAM), a methyl donor generated from methionine. GSCs contained lower levels of methionine, SAM, and nicotinamide, but they contained higher levels of oxidized nicotinamide adenine dinucleotide (NAD+) than differentiated tumor cells. In concordance with the poor prognosis associated with DNA hypomethylation in glioblastoma, depletion of methionine, a key upstream methyl group donor, shifted tumors toward a mesenchymal phenotype and accelerated tumor growth. Targeting NNMT expression reduced cellular proliferation, self-renewal, and in vivo tumor growth of mesenchymal GSCs. Supporting a mechanistic link between NNMT and DNA methylation, targeting NNMT reduced methyl donor availability, methionine levels, and unmethylated cytosine, with increased levels of DNA methyltransferases, DNMT1 and DNMT3A. Supporting the clinical significance of these findings, NNMT portended poor prognosis for glioblastoma patients. Collectively, our findings support NNMT as a GSC-specific therapeutic target in glioblastoma by disrupting oncogenic DNA hypomethylation.
| S-EPMC5436539 | biostudies-literature
Project description:Cancer stem cells (CSCs) are a subpopulation of tumor cells suggested to be critical for tumor maintenance, metastasis, and therapeutic resistance. Prospective identification and targeting of CSCs are therefore priorities for the development of novel therapeutic paradigms. Although CSC enrichment has been achieved with cell surface proteins including CD133 (Prominin-1), the roles of current CSC markers in tumor maintenance remain unclear. We examined the glioblastoma stem cell (GSC) perivascular microenvironment in patient specimens to identify enrichment markers with a functional significance and identified integrin alpha6 as a candidate. Integrin alpha6 is coexpressed with conventional GSC markers and enriches for GSCs. Targeting integrin alpha6 in GSCs inhibits self-renewal, proliferation, and tumor formation capacity. Our results provide evidence that GSCs express high levels of integrin alpha6, which can serve not only as an enrichment marker but also as a promising antiglioblastoma therapy.
| S-EPMC2884275 | biostudies-literature