CD24 is a potential oncogene reported to be overexpressed in a large variety of human malignancies. We have shown that CD24 is overexpressed in 90% of colorectal tumors at a fairly early stage in the multistep process of carcinogenesis. Anti-CD24 monoclonal antibodies (mAb) induce a significant growth inhibition in colorectal and pancreatic cancer cell lines that express the protein. This study is designed to investigate further the effects of CD24 down-regulation using mAb or small interfering RNA in vitro and in vivo. Western blot analysis showed that anti-CD24 mAb induced CD24 protein down-regulation through lysosomal degradation. mAb augmented growth inhibition in combination with five classic chemotherapies. Xenograft models in vivo showed that tumor growth was significantly reduced in mAb-treated mice. Similarly, stable growth inhibition of cancer cell lines was achieved by down-regulation of CD24 expression using short hairpin RNA (shRNA). The produced clones proliferated more slowly, reached lower saturation densities, and showed impaired motility. Most importantly, down-regulation of CD24 retarded tumorigenicity of human cancer cell lines in nude mice. Microarray analysis revealed a similar pattern of gene expression alterations when cells were subjected to anti-CD24 mAb or shRNA. Genes in the Ras pathway, mitogenactivated protein kinase, or BCL-2 family and others of oncogenic association were frequently down-regulated. As a putative new oncogene that is overexpressed in gastrointestinal malignancies early in the carcinogenesis process, CD24 is a potential target for early intervention in the prevention and treatment of cancer.
Targeting CD24 for treatment of colorectal and pancreatic cancer by monoclonal antibodies or small interfering RNA.
Specimen part, Cell line
View SamplesWe demonstrate that the G protein Gi3 is the cellular target of the adenosine A3 receptor (A3R). By using a cell permeable peptide comprising the C-terminal end of Gi3 fused to an importation sequence (ALL1) as a selective inhibitor of Gi3 signaling, we show that by coupling to Gi3, the A3R stimulates multiple signaling pathways in human mast cells, leading to upregulation of cytokines, chemokines and growth factors.Following contact with activated T cell membranes, endogenous adenosine binds to and activates the A3R, resulting in Gi3-mediated signaling. Specifically, the majority of ERK1/2 signaling initiated by contact with activated T cell membranes, is mediated by Gi3, giving rise to ALL1-inhibitable cellular responses. These results unveil the physiological GPCR that couples to Gi3 and establish the important role played by this G-protein in inflammatory conditions that involve adenosine-activated mast cells.
Activation of mast cells by trimeric G protein Gi3; coupling to the A3 adenosine receptor directly and upon T cell contact.
Cell line
View SamplesParental imprinting is a form of epigenetic regulation that results in parent-of-origin differential gene expression. To study Prader-Willi syndrome (PWS), a developmental imprinting disorder, we generated patient-derived induced pluripotent stem cells (iPSCs) harboring distinct deletions in the affected region on chromosome 15. Studying PWS-iPSCs and human parthenogenetic iPSCs unexpectedly revealed substantial upregulation of virtually all maternally expressed genes (MEGs) in the imprinted DLK1-DIO3 locus on chromosome 14. Subsequently, we identified IPW, a long noncoding RNA in the critical region of the PWS locus, as a regulator of the DLK1-DIO3 region, as its over-expression in PWS and parthenogenetic iPSCs results in downregulation of the MEGs in this locus. We further show that gene expression changes in the DLK1-DIO3 region coincide with chromatin modifications, rather than DNA methylation levels. Our results suggest that a subset of PWS phenotypes may arise from dysregulation of an imprinted locus distinct from the PWS region.
The noncoding RNA IPW regulates the imprinted DLK1-DIO3 locus in an induced pluripotent stem cell model of Prader-Willi syndrome.
Sex, Specimen part
View SamplesDiploidy is a fundamental genetic feature in mammals, in which haploid cells normally arise only as post-meiotic germ cells that serve to insure a diploid genome upon fertilization. Gamete manipulation has yielded haploid embryonic stem (ES) cells from several mammalian species, but as of yet not from humans. Here we analyzed a large collection of human parthenogenetic ES cell lines originating from haploid oocytes, leading to the successful isolation and maintenance of human ES cell lines with a normal haploid karyotype. Haploid human ES cells exhibited typical pluripotent stem cell characteristics such as self-renewal capacity and a pluripotency-specific molecular signature. Although haploid human ES cells resembled their diploid counterparts, they also displayed distinct properties including differential regulation of X chromosome inactivation and genes involved in oxidative phosphorylation, alongside reduction in absolute gene expression levels and cell size. Intriguingly, we found that a haploid genome is compatible not only with the undifferentiated pluripotent state, but also with differentiated somatic fates representing all three embryonic germ layers, despite a persistent dosage imbalance between the autosomes and X chromosome. We expect that haploid human ES cells will provide novel means for studying human functional genomics, development and evolution. Overall design: RNA sequencing analysis was performed on a total of 2 samples of in vitro fertilization (IVF) control embryonic stem cell lines.
Derivation and differentiation of haploid human embryonic stem cells.
No sample metadata fields
View SamplesDiploidy is a fundamental genetic feature in mammals, in which haploid cells normally arise only as post-meiotic germ cells that serve to insure a diploid genome upon fertilization. Gamete manipulation has yielded haploid embryonic stem (ES) cells from several mammalian species, but as of yet not from humans. Here we analyzed a large collection of human parthenogenetic ES cell lines originating from haploid oocytes, leading to the successful isolation and maintenance of human ES cell lines with a normal haploid karyotype. Haploid human ES cells exhibited typical pluripotent stem cell characteristics such as self-renewal capacity and a pluripotency-specific molecular signature. Although haploid human ES cells resembled their diploid counterparts, they also displayed distinct properties including differential regulation of X chromosome inactivation and genes involved in oxidative phosphorylation, alongside reduction in absolute gene expression levels and cell size. Intriguingly, we found that a haploid genome is compatible not only with the undifferentiated pluripotent state, but also with differentiated somatic fates representing all three embryonic germ layers, despite a persistent dosage imbalance between the autosomes and X chromosome. We expect that haploid human ES cells will provide novel means for studying human functional genomics, development and evolution.
Derivation and differentiation of haploid human embryonic stem cells.
Specimen part, Cell line
View SamplesV600E being the most common mutation in BRAF, leads to constitutive activation of the MAPK signaling pathway. The majority of V600E BRAF positive melanoma patients treated with the BRAF inhibitor vemurafenib showed initial good clinical responses but relapsed due to acquired resistance to the drug. The aim of the present study was to identify possible biomarkers associated with the emergence of drug resistant melanoma cells. To this end we analyzed the differential gene expression of vemurafenib-sensitive and vemurafenib resistant brain and lung metastasizing melanoma cells.
Vemurafenib resistance selects for highly malignant brain and lung-metastasizing melanoma cells.
Specimen part, Treatment
View SamplesLy6Chi monocytes massively infiltrate the CRC-tumors by virtue of their CCR2 expression and further mature into Ly6CloF4/80hi CD64hiMHCII+ TAM upon tumor progression. We demonstrated that TAM-deficient tumors display impaired tumor-growth via alternation of the ECM morphology, structure and composition. Using advanced high-resolution optical imaging to visualize the tumoral-ECM macromolecule network together with transcriptomic and proteomic approaches we unraveled that TAM play critical role in the deposition, linearization and cross-linking of collagenous ECM. Remarkably, we show that cues embedded in ECM by TAM-mediated remodeling activity promote tumor cell proliferation in vitro and orthotopic tumor development in vivo.
Tumor macrophages are pivotal constructors of tumor collagenous matrix.
Sex, Specimen part
View SamplesWe treated melanoma cells with BRAF mutation with BRAF inhibitor and screened for BRAF inhibitor resistant cells. We extracted total mRNA from parental cells and resistant cell lines. We compared their expression by carried out Affymetrix Huex 1.0 ST expression array.
Epigenetic changes of EGFR have an important role in BRAF inhibitor-resistant cutaneous melanomas.
No sample metadata fields
View SamplesHuman pluripotent stem cells can be derived from somatic cells by forced expression of defined factors, and more recently by nuclear-transfer into human oocytes, revitalizing a debate on whether one reprogramming approach might be advantageous over the other. Here we compared the genetic and epigenetic stability of human nuclear-transfer embryonic stem cell (NT-ESC) lines and isogenic induced pluripotent stem cell (iPSC) lines, derived from the same somatic cell cultures of fetal, neonatal and adult origin. Both cell types shared similar genome-wide gene expression and DNA methylation profiles. Importantly, NT-ESCs and iPSCs have comparable numbers of de novo coding mutations but significantly higher than parthenogenetic ESCs. Similar to iPSCs NT-ESCs displayed clone- and gene-specific aberrations in DNA methylation and allele-specific expression of imprinted genes, similarly to iPSCs. The occurrence of these genetic and epigenetic defects in both NT-ESCs and iPSCs suggests that they are inherent to reprogramming, regardless of the underlying technique. Overall design: RNA sequencing analysis was performed on a total of 12 human cell lines, including: an isogenic set of 3 nuclear-transfer embryonic stem cell (NT-ESC) lines, 2 RNA-reprogrammed induced pluripotent stem cell (iPSC) lines and their parental neonatal fibroblast cell line; an isogenic set of 1 NT-ESC line, 3 iPSC lines and their parental adult fibroblast cell line (derived from a type 1 diabetic subject); as well as 1 control embryonic stem cell (ESC) line.
Comparable frequencies of coding mutations and loss of imprinting in human pluripotent cells derived by nuclear transfer and defined factors.
No sample metadata fields
View SamplesThe balance between protecting tissue integrity and efficient immune response is critical for host survival. Here we investigate the role of extracellular matrix (ECM) proteolysis in achieving this balance in the lung during influenza virus infection using a combined genomic and proteomic approach. We followed the transcriptional dynamics and ECM- related responses in a mouse model of influenza virus infection, integrated with whole tissue imaging and functional assays. Our study identifies MT1-MMP as a prominent host-ECM-remodeling collagenase in influenza virus infection. We show that selective inhibition of MT1-MMP-driven ECM proteolysis protects the tissue from infection-related structural and compositional damage. Inhibition of MT1-MMP did not significantly alter the immune response or cytokine expression, indicating its dominant role in ECM remodeling. We demonstrate that the available treatment for influenza virus (Tamiflu/ Oseltamivir) does not prevent lung ECM damage and is less effective than anti-MT1-MMP treatment in influenza virus and Streptococcus pneumoniae coinfection paradigms. Importantly, combination therapy of Tamiflu with anti-MT1-MMP shows a strong synergistic effect and results in complete recovery in mice. This study highlights the importance of tissue tolerance agents for surviving infectious diseases, and the potential of such host-pathogen therapy combination for respiratory infections. Overall design: Overall 8 samples were included, in duplicates, both infected and non-infected control cells were includeda. Both MT1-MMP positive and MT1-MMP negative were tested were non-infectdd, MT1-MMP negative cells served as controls.
Extracellular Matrix Proteolysis by MT1-MMP Contributes to Influenza-Related Tissue Damage and Mortality.
Specimen part, Cell line, Treatment, Subject
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