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Homo sapiens
7 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Targeting the estrogen signaling pathway has proved to be of great value in the treatment of human breast cancer. Tamoxifen, a selective estrogen receptor modulator (SERM), is the most widely used antiestrogen. However, only 40-50% of patients with estrogen receptor (ER) positive breast cancer benefit from tamoxifen treatment and 30-50% acquire resistance and the disease progresses. Continuous treatment with conventional therapy may contribute to cancer progression in recurring cancers through the accumulation of drug resistant cancer progenitors. We found that MCF7 tamoxifen-resistant (TAM-R) cells possess a significantly higher proportion of cancer progenitor cells than tamoxifen-sensitive MCF7 cells. Our results indicate that the chemokine receptor CXCR4 plays an important role in the maintenance of cancer progenitors in a tamoxifen-resistant cell line and downregulation of CXCR4 signaling by small molecule antagonists specifically inhibits growth of a stem-like cell population in tamoxifen-resistant tumors both in vitro and in vivo. Whole genome gene expression analysis revealed aryl hydrocarbon receptor (AhR) signaling as one of the top networks that is differentially regulated in MCF7(TAM-R) xenograft tumors treated with the CXCR4 antagonist AMD3100 as compared to MCF7 tumors. Further, small molecule antagonists of AhR signaling specifically inhibit the progenitor population in MCF7(TAM-R) cells suggesting that the aryl hydrocarbon receptor could be a putative target for the treatment of tamoxifen-resistant breast cancers. Introduction transplants remains limited by the ability to expand these cells ex vivo. An unbiased screen with primary human HSCs identified a purine derivative, StemRegenin 1 (SR1), that promotes the ex vivo expansion of CD34+ cells. Culture of HSCs with SR1 led to a 50-fold increase in cells expressing CD34 and a 17-fold increase in cells that retain the ability to engraft immunodeficient mice. Mechanistic studies show that SR1 acts by antagonizing the aryl hydrocarbon receptor (AHR). The identification of SR1 and AHR modulation as a means to induce ex vivo HSC expansion should facilitate the clinical use of HSC therapy.
Publication Title
CXCR4 activation maintains a stem cell population in tamoxifen-resistant breast cancer cells through AhR signalling.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 3 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Self-renewing tumor initiating cells that are capable of differentiation and responsible for tumor growth have been isolated from cancers and cell lines. If such minor populations are associated with tumor progression, understanding molecular pathways that are required for viability and maintenance of these populations will allow to target these pathways to eradicate tumors that are resistant to existing therapies. In this study we enriched for prostate cancer progenitors (Pr. CPs) expressing cell surface markers CD44/CD133/alpha 2 beta 1 integrin in non-adherent serum-free growth conditions maintained as spheres. Cells grown in these conditions have increased in vivo clonogenic and in vivo tumorigenic potential. microarray analysis of cells grown in sphere conditions compared with long term monolayer culture conditions revealed preferential activation of PI3K/AKT pathway in prostate cancer progenitors. PI3K p110 alpha and beta protein levels were high in sphere condition cultured cells, and PTEN knockdown lead to an increase in Pr.CPs, and to increased clonogenic and tumorigenic potential. Inhibition of Akt1 phosphorylation target FoxO3a lead to inhibition of tumorigenic capacity in vivo for prostate cancer cells. Inhibition of PI3K activity by PI3K inhibitor NVP-BEZ235 lead to a selective inhibition of Pr.CPs, nuclear localization of FoxO3a and increase in GADD45a in prostate cancer cells. Taken together our data strongly suggest that PTEN and PI3K/Akt pathways are critical for prostate cancer stem-like cell maintenance and targeting the PI3K signaling by selective inhibitors may give an incredible advancement in prostate cancer treatment.
Publication Title
The role of PTEN/Akt/PI3K signaling in the maintenance and viability of prostate cancer stem-like cell populations.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
The basic helix-loop-helix (bHLH) transcription factor hairy and enhancer of split (Hes3) is a member of the Hes/Hey gene family that regulates developmental processes in progenitor cells from various tissues. We demonstrated the Hes3 expression in mouse pancreatic tissue, suggesting it may have a role in modulating beta-cell function. We employed a transfection approach to address specific functions of Hes3. Hes3 RNA interference opposed the growth of the mouse insulinoma cell line Min6. Western blotting and PCR approaches specifically showed that Hes3 RNA interference opposes the expression of Pdx1 and insulin. Likewise, Hes3 knock down reduced evoked insulin release from Min6 cells.
Publication Title
Hes3 is expressed in the adult pancreatic islet and regulates gene expression, cell growth, and insulin release.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
A large body of evidence has demonstrated that many human tumors are maintained by a small cell population called cancer stem cells (CSCs) or tumor progenitors, which are responsible for tumor formation, therapy resistance and metastasis. We found that ionizing radiation treatment enriches for the CSC phenotype and properties by preferential survival and expansion of tumor progenitor cells. Our studies revealed that aldehyde dehydrogenase (ALDH) activity is indicative of prostate tumor progenitor cells with increased chemo- and radioresistance, enhanced migratory potential, improved DNA- double strand break repair and activation of the signaling pathways, which promote self-renewal and epithelial-mesenchymal transition. We found that X-ray irradiation can convert the bulk tumor cells to more clonogenic and radioresistant population positive for expression of CSC markers. For the first time we showed that irradiation increases histone H3K4 and H3K36 methylation in prostate cancer cells, thereby reactivating transcription of epigenetically silenced target genes. We showed that radioresistant tumor progenitor population undergoes a phenotypical switching during the course of irradiation, suggesting that controlling the phenotypical and functional properties of CSCs during radiation therapy is ultimative for the optimization of treatment strategies. Our studies have shown that CSC markers may be beneficial in prediction of tumor radiocurability, and combination of irradiation with therapies directed against CSCs can be a useful strategy to improve cancer treatment.
Publication Title
Aldehyde Dehydrogenase Is Regulated by β-Catenin/TCF and Promotes Radioresistance in Prostate Cancer Progenitor Cells.
Sample Metadata Fields
Specimen part
View Samples- Sus scrofa
- 18 Downloadable Samples
- Affymetrix Porcine Genome Array (porcine)
Description
Enterotoxigenic Escherichia coli (ETEC) strains that produce both heat-stable (ST) and heat-labile (LT) enterotoxins cause severe post-weaning diarrhea in piglets. However, the relative importance of the individual enterotoxins to the pathogenesis of ETEC infection is poorly understood. In this study, we investigated the effect on virulence of an F4+ ETEC strain when removing some or all of its enterotoxins. Several isogenic mutant strains were constructed that lack the expression of LT in combination with one or both types of ST enterotoxins (STa and/or STb). Host early immune responses induced by these mutant strains 4h after infection were compared to the wild type strain GIS26 (O149:F4ac+, LT+ STa+ STb+). At the same time, the immune response of this wild type ETEC strain was compared to the mock-infected control, demonstrating the expression of porcine inflammatory response genes. For these purposes, the small intestinal segment perfusion (SISP) technique and microarray analysis were used and results were validated by qRT-PCR. We also measured net fluid absorption of pig small intestinal mucosa 4h after infection with wild type ETEC, the mutant strains and PBS (mock-infected). These data indicate an important role for STb in inducing small intestinal secretion early after infection. The microarray analysis of the different mutant strains also revealed an important role for STb in ETEC-induced immune response by the significant differential regulation of immune mediators like matrix metalloproteinase 3, interleukin 1 and interleukin 17. We conclude that STb can play a prominent role in ETEC-induced secretion and early immune response.
Publication Title
Role of heat-stable enterotoxins in the induction of early immune responses in piglets after infection with enterotoxigenic Escherichia coli.
Sample Metadata Fields
Sex, Specimen part, Treatment
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Masitinib is a tyrosine kinase inhibitor of c-Kit, PDGFR and , and to some extent Lyn of the Src kinase family. We evaluated the therapeutic potential of masitinib in vitro on human pancreatic tumour cell lines and in vivo in a mouse model of human pancreatic cancer.
Publication Title
Masitinib combined with standard gemcitabine chemotherapy: in vitro and in vivo studies in human pancreatic tumour cell lines and ectopic mouse model.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Homo sapiens
- 15 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
IFN alpha mediated gene expression pattern. The effect of IFN alpha on human CD8 T cells responding to antigen (signal 1) and costimulatory signals (signal 2) provided by beads coated with anti-CD3 and anti-CD28 mAbs.
Publication Title
Effects of IFN-α as a signal-3 cytokine on human naïve and antigen-experienced CD8(+) T cells.
Sample Metadata Fields
Specimen part, Subject, Time
View Samples- Mus musculus
- 4 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Most adult patients have a D816V mutation in phosphotransferase domain (PTD), we have described that half of the children carry mutations in extracellular domain (ECD). KIT-ECD versus IT-PTD-mutants were introduced into rodent Ba/F3, EML, Rat2 and human TF1 cells to investigate their biological effect. ECD- and PTD-mutants also displayed distinct whole-genome transcriptional profiles in EML cells. We observed differences in their signaling properties: they both activated STAT pathways, whereas AKT pathway was only activated by ECD-mutants. Consistently, AKT inhibitor suppressed ECD-mutant-dependent proliferation, clonogenicity and erythroid differentiation. Expression of myristoylated AKT restored erythroid differentiation in EMLPTD cells, suggesting the differential role of AKT in those mutants. Overall, our study implied different pathogenesis of pediatric versus adult mastocytosis, which might explain their diverse phenotypes.
Publication Title
Pediatric mastocytosis-associated KIT extracellular domain mutations exhibit different functional and signaling properties compared with KIT-phosphotransferase domain mutations.
Sample Metadata Fields
Cell line, Time
View Samples- Mus musculus
- 4 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
CCR6+ innate lymphoid cells were sorted from the mesenteric lymph node of nave C57BL/6 mice
Publication Title
Immune tolerance. Group 3 innate lymphoid cells mediate intestinal selection of commensal bacteria-specific CD4⁺ T cells.
Sample Metadata Fields
Specimen part
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GSE90471- Mus musculus
- 9 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
3 samples of R1, R2 and R3 bone marrow monocytes were compared from 3 biological replicates in 3 separate experiments.
Publication Title
The Heterogeneity of Ly6C<sup>hi</sup> Monocytes Controls Their Differentiation into iNOS<sup>+</sup> Macrophages or Monocyte-Derived Dendritic Cells.
Sample Metadata Fields
Specimen part
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