Astrocytes react to brain injury in a heterogeneous manner with only a subset resuming proliferation and acquiring in vitro neural stem cell properties. In order to identify novel regulators of this astrocyte subset, we performed a genome-wide expression analysis of reactive astrocytes isolated 5 days after stab wound injury from the adult mouse cerebral cortex. The expression pattern was compared with astrocytes from normal cortex and adult neural stem cells isolated from the sub-ependymal zone (GSE18765). These comparisons revealed a set of genes up-regulated both in neurogenic neural stem cells and reactive astrocytes, including the lectins Galectin-1 and -3. These results, as well as the pattern of Galectin expression in the lesioned brain, led us to examine the functional significance of these lectins in brains of Galectin-1/3 double-knockout mice.
Astrocyte reactivity after brain injury-: The role of galectins 1 and 3.
Sex, Specimen part, Treatment, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Discovery of first-in-class reversible dual small molecule inhibitors against G9a and DNMTs in hematological malignancies.
Cell line, Treatment
View SamplesThe indisputable role of epigenetics in cancer and the fact that epigenetic alterations can be reversed have favored development of epigenetic drugs. In this study, we have design and synthesize potent novel, selective and reversible chemical probes that simultaneously inhibit the G9a and DNMTs methyltransferase activity. In vitro treatment of hematological neoplasia (Acute Myeloid Leukemia-AML, Acute Lymphoblastic Leukemia-ALL and Diffuse Large B-cell Lymphoma-DLBCL) with the lead compound CM-272, inhibited cell proliferation and promoted apoptosis, inducing interferon stimulated genes and immunogenic cell death. CM-272 significantly prolonged survival of AML, ALL and DLBCL xenogeneic models. Our results represent the discovery of first-in-class dual inhibitors of G9a/DNMTs and establish this chemical series, as a promising therapeutic tool for unmet needs in hematological tumors.
Discovery of first-in-class reversible dual small molecule inhibitors against G9a and DNMTs in hematological malignancies.
Cell line, Treatment
View SamplesTransgenic expression of TLX1 induces T-cell leukemias in mice.
The TLX1 oncogene drives aneuploidy in T cell transformation.
No sample metadata fields
View SamplesA significant proportion of patients with oestrogen receptor (ER) positive breast cancers (BC) develop resistance to endocrine treatments (ET) and relapse with metastatic disease. Bone is the most common metastatic site in ER+ patients, however bone metastases are technically challenging to biopsy and analyse. Difficulties concern both tumour tissue acquisition and techniques for analysis and RNA extractions. Patient-derived xenografts (PDX) of BC bone metastases have not been reported yet. For the first time we established PDX models from bone metastatic biopsies of patients progressing on ET and treated by vertebroplasty. PDX models were analysed at transcriptomic level and compared to patient’s early primary tumours to identify new therapeutic targets associated with endocrine resistance in the metastatic setting.
PLK1 inhibition exhibits strong anti-tumoral activity in CCND1-driven breast cancer metastases with acquired palbociclib resistance.
Disease, Disease stage, Treatment
View SamplesAvian pathogenic Escherichia coli strains frequently cause extra-intestinal infections and are responsible for significant economic losses in the poultry industry worldwide. APEC isolates are closely related to human extraintestinal pathogenic E.coli strains and may also act as pathogens for humans. In this work, three type VI secretion systems were deleted to analyze which pathogenicity characteristics would change in the mutants, compared to wild type strain (SEPT 362).
The type VI secretion system plays a role in type 1 fimbria expression and pathogenesis of an avian pathogenic Escherichia coli strain.
No sample metadata fields
View SamplesIn rats, learning and memory performance decline during normal aging, which makes this rodent species a suitable model to evaluate therapeutic strategies. In aging rats, insulin-like growth factor-I (IGF-I), is known to significantly improve spatial memory accuracy as compared to control counterparts. A constellation of gene expression changes underlie the hippocampal phenotype of aging but no studies on the effects of IGF-I on the hippocampal transcriptome of old rodents have been documented. Here, we assessed the effects of IGF-I gene therapy on spatial memory performance in old female rats and compared them with changes in the hippocampal transcriptome. Overall design: Hippocampal RNA-Seq profiles of 28 months old rats intracerebroventricularly injected with an adenovector expressing rat IGF-I was compared with placebo adenovector-injected counterparts (4 samples each group)
IGF-I Gene Therapy in Aging Rats Modulates Hippocampal Genes Relevant to Memory Function.
No sample metadata fields
View SamplesAlthough new therapies have doubled the survival of multiple myeloma (MM) patients, this remains an incurable disease. It has been postulated that the so-called MM Cancer Stem Cells (MM-CSC) would be responsible for tumor initiation and relapse but their unequivocal identification remains unclear. Here, we investigated in a panel of MM cell lines the presence of CD20+ cells harboring a MM-CSC phenotype. Among the multiple cell lines investigated, only a small population of CD20dim+ cells (0.3%) in the RPMI-8226 cell line was found. CD20dim+ RPMI-8226 cells expressed the plasma cell markers CD38 and CD138 and were CD19-CD27-. Additionally, CD20dim+ RPMI-8226 cells did not exhibit stem-cell markers as shown by gene expression profiling and the aldehyde dehydrogenase (ALDH) assay. Moreover, we demonstrated that CD20dim+ RPMI-8226 cells are not essential for CB17-SCID mice engraftment and show lower self-renewal potential than the CD20- RPMI-8226 cells. These results do not support CD20+ expression for the identification of MM-CSC.
CD20 positive cells are undetectable in the majority of multiple myeloma cell lines and are not associated with a cancer stem cell phenotype.
No sample metadata fields
View SamplesDespite recent advances in the treatment of multiple myeloma (MM), it remains an incurable disease potentially due to the presence of resistant myeloma cancer stem cells (MM-CSC). Although the presence of clonogenic cells in MM was described more than 30 years ago, the phenotype of MM-CSC is still a matter of debate, especially with respect to the expression of syndecan- 1 (CD138). Here, we demonstrate the presence of two subpopulations - CD138++ (95-99%) and CD138low (1-5%) - in eight MM cell lines. To find out possible stem-cell-like features, we have phenotypically, genomic and functionally characterized the two subpopulations. Our results show that the minor CD138low subpopulation is morphologically identical to the CD138++ fraction and does not represent a more immature B-cell compartment (with lack of CD19, CD20 and CD27 surface expression). Moreover, both subpopulations have similar gene expression and genomic profiles. Importantly, both CD138++ and CD138low subpopulations have similar sensitivity to bortezomib, melphalan and doxorubicin. Finally, serial engraftment in SCID mice shows that CD138++ as well as CD138low cells have self-renewal potential and they are also phenotypically interconvertible. Overall, our results differ from previously published data which attribute a B-cell phenotype to MM-CSC and urge the need to explore more reliable markers to discriminate true clonogenic myeloma cells.
Phenotypic, genomic and functional characterization reveals no differences between CD138++ and CD138low subpopulations in multiple myeloma cell lines.
Disease, Cell line
View SamplesThe discovery of mammalian cardiac progenitor cells has suggested that the heart consists of not only terminally differentiated beating cardiomyocytes, but also a population of self-renewing stem cells with the potential to generate new cardiomyocytes (Anderson, Self et al. 2007; Bearzi, Rota et al. 2007; Wu, Chien et al. 2008). A consequence of longevity is continual exposure to environmental and xenobiotic stresses, and recent literature suggests that hematopoietic stem cell pools tightly control cell health through upregulation of the integrated stress response and consequent cellular mechanisms such as apoptosis. However, whether or not this biological response is conserved in progenitor cells for later lineages of tissue specific stem cells is not well understood. Using human induced pluripotent stem cells (iPSC) of both cardiac progenitor and mature cardiomyocyte lineages, we found that the integrated stress response was upregulated in the iPSC cardiac progenitors leading to an increased sensitivity for apoptosis relative to the mature cardiomyocytes. Of interest, C/EBP homologous protein (CHOP) signaling plays a mechanistic role in the cell death phenotype observed in iPSC progenitors, by which depletion of CHOP prevents cell death following cellular stress by thapsigargin exposure. Our studies suggest that the integrated stress response plays a unique role in maintaining iPSC cardiac progenitor cellular integrity by removing unhealthy cells via apoptosis following environmental and xenobiotic stresses, thus preventing differentiation and self-renewal of damaged cells.
The Integrated Stress Response Regulates Cell Health of Cardiac Progenitors.
Specimen part, Treatment
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