Hematopoietic stem cells (HSCs) are identified by their ability to sustain prolonged blood cell production in vivo, although recent evidence suggests that durable self-renewal (DSR) is shared by HSC subtypes with distinct self-perpetuating differentiation programs. Net expansions of DSR-HSCs occur in vivo, but molecularly defined conditions that support similar responses in vitro are lacking. We hypothesized that this might require a combination of factors that differentially promote HSC viability, proliferation and self-renewal. We now demonstrate that HSC survival and maintenance of DSR potential is variably supported by different Steel factor (SF)-containing cocktails with similar HSC-mitogenic activities. In addition, stromal cells produce other factors, including nerve growth factor and collagen 1, that can antagonize the apoptosis of initially quiescent adult HSCs and, in combination with SF and interleukin-11, produce >15-fold net expansions of DSR-HSCs ex vivo within 7 days. These findings suggest a new molecular basis for HSC control and expansion.
Distinct stromal cell factor combinations can separately control hematopoietic stem cell survival, proliferation, and self-renewal.
Specimen part
View SamplesThe experiment was designed to generate a time series for epithelial model during development. Each time point had 3 replicates. The data set contained 5 time points over 10 days. They are day0, day3, day5,day7,day10.
Dynamic and physical clustering of gene expression during epidermal barrier formation in differentiating keratinocytes.
Age, Specimen part, Time
View SamplesMouse haematopoietic stem cells (HSCs) undergo a post-natal transition in several properties, including a marked reduction in their self-renewal activity. We now show that the developmentally timed change in this key function of HSCs is associated with their decreased expression of Lin28b and an accompanying increase in their let-7 microRNA levels. Lentivirus(LV)-mediated overexpression of Lin28 in adult HSCs elevates their self-renewal activity in transplanted irradiated hosts, as does overexpression of Hmga2, a well-established let-7 target that is upregulated in fetal HSCs. Conversely, HSCs from fetal Hmga2-/- mice do not display the heightened self-renewal activity that is characteristic of wild-type fetal HSCs. Interestingly, overexpression of Hmga2 in adult HSCs does not mimic the ability of elevated Lin28 to activate a fetal lymphoid differentiation program. Thus Lin28b may act as a master regulator of developmentally timed changes in HSC programs with Hmga2 serving as its specific downstream modulator of HSC self-renewal potential.
The Lin28b-let-7-Hmga2 axis determines the higher self-renewal potential of fetal haematopoietic stem cells.
Specimen part
View SamplesMale C57BL/6 mice were treated with ENU to generate single base substitutions, the variant genome sequences were breed to homozygosity in inbreeding pedigrees, and screened for antinuclear autoantibodies (ANA). The sanroque pedigree contained multiple progeny with ANA of mixed homogeneous nuclear and cytoplasmic immunofluorescence pattern by 12 weeks of age, due to an autosomal recessive gene variant. Comparison of the gene expression profile of CD4 cells from Sanroque to wild type was performed.
A RING-type ubiquitin ligase family member required to repress follicular helper T cells and autoimmunity.
No sample metadata fields
View SamplesCurrently there is a lack of effective therapies which result in long-term durable response for patients presenting with advanced and metastatic clear cell renal cell carcinoma (ccRCC). This is due in part to a lack of molecular factors which can be targeted pharmacologically. In order to identify novel tumor-specific targets, we performed high throughput gene array analysis screening numerous patient ccRCC tumor tissues across all stages of disease, and compared their gene expression levels to matched normal kidney. Our results identify a number of genes which demonstrate tumor-specific overexpression, and may present as novel targets for therapy.
Neuronal pentraxin 2 supports clear cell renal cell carcinoma by activating the AMPA-selective glutamate receptor-4.
Specimen part
View SamplesCurrently there is a lack of effective therapies which result in long-term durable response for patients presenting with anaplastic thyroid carcinoma (ATC), a very rare and lethal variant of thyroid cancer. ATC is resistant to chemotherapy, radiation, and targeted therapies currently available. In an effort to identify novel tumor-specific therapeutic targets, we performed high throughput gene array analysis screening numerous patient ATC tumor tissues, and compared their gene expression levels to matched and unmatched normal thyroid tissue samples.
Aberrant lipid metabolism in anaplastic thyroid carcinoma reveals stearoyl CoA desaturase 1 as a novel therapeutic target.
Specimen part
View SamplesPresently, there is a deficiency of effective therapies designed to target clear cell renal cell carcinoma (ccRCC), with poor prognosis resulting in patients with advanced disease. Additionally, there is a lack of molecular factors which can be remedially targeted resulting in tumor specific inhibition, and therefore current therapeutic approaches often produce adverse side effects in patients. We identified that Stearoyl-CoA desaturase 1 (SCD1) was consistently overexpressed in patient ccRCC samples, and further investigation of SCD1 as a potential molecular target for ccRCC intervention utilizing a SCD1 inhibitor (A939572) resulted in tumor specific growth inhibition and induction of cell death. In order to understand the mechanism by which the SCD1 inhibitor mediated its anti-tumor effects, we performed gene array analysis and compared expression patterns between treated and untreated samples.
Stearoyl-CoA desaturase 1 is a novel molecular therapeutic target for clear cell renal cell carcinoma.
Cell line, Treatment
View SamplesAlthough renal cell carcinoma (RCC) is the sixth-leading cause of cancer death, the molecular events leading to disease onset and progression are not well understood. Genomic profiling of clear cell RCC (cRCC) patients indicated that loss of a negative regulator of the Wnt pathway, secreted frizzled-related protein 1 (sFRP1), occurred in the majority of more than 100 patients tested. To our knowledge, this is the first report of loss of sFRP1 expression in patients diagnosed with cRCC; this loss occurs in early stage cRCC, suggesting that it may be an important early event in renal carcinogenesis. Genomic profiling of patient matched normal and cRCC tissues identified Wnt regulated genes to be aberrantly increased in cRCC tissues suggesting sFRP1 suppresses Wnt signaling in cRCC. In order to test the hypothesis that sFRP1 acts as a tumor suppressor in cRCC, we have stably expressed sFRP1 in cRCC cells. sFRP1 expression in cRCC cells resulted in decreased growth in cell culture, inhibition of anchorage-independent growth, and decreased tumor volume in a nude mouse model. Together these data suggest an important role for sFRP1 as a tumor suppressor in cRCC.
Secreted frizzled-related protein 1 loss contributes to tumor phenotype of clear cell renal cell carcinoma.
No sample metadata fields
View SamplesThis data was used to determine levels of BRCA1 and BRCA2 in primary human leukemia samples. Samples were determined to be high BRCA1 and/or BRCA2 or low BRCA1 and/or BRAC2.
Personalized synthetic lethality induced by targeting RAD52 in leukemias identified by gene mutation and expression profile.
No sample metadata fields
View SamplesA comparison of global gene expression between rigorously defined stem and progenitor cells from patients with chronic myeloid leukaemia (CML) in chronic (CP), accelerated (AP) and blastic (BC) phase and similar populations isolated from normal volunteers.
Personalized synthetic lethality induced by targeting RAD52 in leukemias identified by gene mutation and expression profile.
Specimen part, Disease, Disease stage, Subject
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