This SuperSeries is composed of the SubSeries listed below.
Integrated gene and miRNA expression analysis of prostate cancer associated fibroblasts supports a prominent role for interleukin-6 in fibroblast activation.
Specimen part, Treatment
View SamplesTumor microenvironment coevolves with and simultaneously sustains cancer progression. Reactive fibroblasts found in prostate cancer (PCa), known as cancer associated fibroblasts (CAF), have been indeed shown to fuel tumor development and metastasis by mutually interacting with PCa cells. Little is known about the molecular mechanisms that lead to activation of CAFs from tissue-resident fibroblasts, circulating marrow-derived fibroblast progenitors or mesenchymal stem cells. Through integrated gene and microRNA expression profiling, here we showed that transcriptome of CAFs isolated from prostate tumors strictly resembles that of normal fibroblasts stimulated in vitro with interleukin-6 (IL6), thus confirming the capability of the cytokine to promote acquisition of an activated and cancer-promoting phenotype, and, for the first time, proving that IL6 is able per se to induce all the complex transcriptional changes characteristic of patient-derived CAFs. Comparison with publicly available datasets, however, suggested that prostate CAFs may be alternatively characterized by IL6 and TGF-related signatures, indicating that either signal, depending on the context, tumor stage and etiology, may concur to fibroblast activation. Our analyses also highlighted pathways relevant for induction of reactive stroma, including genes the role of which in fibroblast activation is still to be explored. In addition, we revealed a role for muscle-specific miR-133b as a soluble factor secreted by activated fibroblasts to support paracrine activation of non-activated fibroblasts or promote tumor progression. Overall, in this study we provided insights on the molecular mechanisms driving fibroblast activation in prostate cancer, thus contributing to identify novel hits for the development of therapeutic strategies targeting the crucial interplay between tumor cells and their microenvironment. Tumor microenvironment coevolves with and simultaneously sustains cancer progression. Reactive fibroblasts found in prostate cancer (PCa), known as cancer associated fibroblasts (CAF), have been indeed shown to fuel tumor development and metastasis by mutually interacting with PCa cells. Little is known about the molecular mechanisms that lead to activation of CAFs from tissue-resident fibroblasts, circulating marrow-derived fibroblast progenitors or mesenchymal stem cells. Through integrated gene and microRNA expression profiling, here we showed that transcriptome of CAFs isolated from prostate tumors strictly resembles that of normal fibroblasts stimulated in vitro with interleukin-6 (IL6), thus confirming the capability of the cytokine to promote acquisition of an activated and cancer-promoting phenotype, and, for the first time, proving that IL6 is able per se to induce all the complex transcriptional changes characteristic of patient-derived CAFs. Comparison with publicly available datasets, however, suggested that prostate CAFs may be alternatively characterized by IL6 and TGF-related signatures, indicating that either signal, depending on the context, tumor stage and etiology, may concur to fibroblast activation. Our analyses also highlighted pathways relevant for induction of reactive stroma, including genes the role of which in fibroblast activation is still to be explored. In addition, we revealed a role for muscle-specific miR-133b as a soluble factor secreted by activated fibroblasts to support paracrine activation of non-activated fibroblasts or promote tumor progression. Overall, in this study we provided insights on the molecular mechanisms driving fibroblast activation in prostate cancer, thus contributing to identify novel hits for the development of therapeutic strategies targeting the crucial interplay between tumor cells and their microenvironment. Tumor microenvironment coevolves with and simultaneously sustains cancer progression. Reactive fibroblasts found in prostate cancer (PCa), known as cancer associated fibroblasts (CAF), have been indeed shown to fuel tumor development and metastasis by mutually interacting with PCa cells. Little is known about the molecular mechanisms that lead to activation of CAFs from tissue-resident fibroblasts, circulating marrow-derived fibroblast progenitors or mesenchymal stem cells. Through integrated gene and microRNA expression profiling, here we showed that transcriptome of CAFs isolated from prostate tumors strictly resembles that of normal fibroblasts stimulated in vitro with interleukin-6 (IL6), thus confirming the capability of the cytokine to promote acquisition of an activated and cancer-promoting phenotype, and, for the first time, proving that IL6 is able per se to induce all the complex transcriptional changes characteristic of patient-derived CAFs. Comparison with publicly available datasets, however, suggested that prostate CAFs may be alternatively characterized by IL6 and TGF-related signatures, indicating that either signal, depending on the context, tumor stage and etiology, may concur to fibroblast activation. Our analyses also highlighted pathways relevant for induction of reactive stroma, including genes the role of which in fibroblast activation is still to be explored. In addition, we revealed a role for muscle-specific miR-133b as a soluble factor secreted by activated fibroblasts to support paracrine activation of non-activated fibroblasts or promote tumor progression. Overall, in this study we provided insights on the molecular mechanisms driving fibroblast activation in prostate cancer, thus contributing to identify novel hits for the development of therapeutic strategies targeting the crucial interplay between tumor cells and their microenvironment.
Integrated gene and miRNA expression analysis of prostate cancer associated fibroblasts supports a prominent role for interleukin-6 in fibroblast activation.
Specimen part, Treatment
View SamplesFollowing androgen ablation therapy (AAT), the vast majority of prostate cancer patients develop treatment resistance with a median time of 18-24 months to disease progression. To identify molecular targets that aid in prostate cancer cell survival and contribute to the androgen independent phenotype, we evaluated changes in LNCaP cell gene expression during 12 months of androgen deprivation. At time points reflecting critical growth and phenotypic changes, we performed Affymetrix expression array analysis to examine the effects of androgen deprivation during the acute response, during the period of apparent quiescence, and during the emergence of highly proliferative, androgen-independent prostate cancer cells (LNCaP-AI). We discovered alterations in gene expression for a host of molecules associated with promoting prostate cancer cell growth and survival, regulating cell cycle progression, apoptosis and adrenal androgen metabolism, in addition to AR co-regulators and markers of neuroendocrine disease. These findings illustrate the complexity and unpredictable nature of cancer cell biology and contribute greatly to our understanding of how prostate cancer cells likely survive AAT. The value of this longitudinal approach lies in the ability to examine gene expression changes throughout the cellular response to androgen deprivation; it provides a more dynamic illustration of those genes which contribute to disease progression in addition to specific genes which constitute a malignant androgen-independent phenotype. In conclusion, it is of great importance that we employ new approaches, such as the one proposed here, to continue exploring the cellular mechanisms of therapy resistance and identify promising targets to improve cancer therapeutics.
Longitudinal analysis of androgen deprivation of prostate cancer cells identifies pathways to androgen independence.
No sample metadata fields
View SamplesmiRNAs are small non-coding RNAs that inhibit translation and promote mRNA decay. The levels of mature miRNAs are the result of different rates of transcription, processing, and turnover. The non-canonical polymerase Gld2 has been implicated in the stabilization of miR-122 possibly by catalyzing 3’ monoadenylation, however, there is little evidence that this relationship is one of cause and effect. Here, we biochemically characterize Gld2 involvement in miRNA monoadenylation and its effect on miRNA stability. We find that Gld2 directly monoadenylates and stabilizes specific miRNA populations in human fibroblasts and that sensitivity to monoadenylation-induced stability depends on nucleotides in the miRNA 3‘ end. These results establish a novel mechanism of miRNA stability and resulting post-transcriptional gene regulation. Overall design: Sequencing of miRNAs to assess amount and 3'' end monoadenylation state upon Gld2 knock-down.
Specific miRNA stabilization by Gld2-catalyzed monoadenylation.
Specimen part, Subject
View SamplesINTRODUCTION. Fixation with formalin, a widely adopted procedure to preserve tissue samples, leads to extensive degradation of nucleic acids and thereby compromises procedures like microarray-based gene expression profiling. We hypothesized that RNA fragmentation is caused by activation of RNAses during the interval between formalin penetration and tissue fixation. To prevent RNAse activation, a series of tissue samples were kept under-vacuum at 4C until fixation and then fixed at 4C, for 24 hours, in formalin followed by 4 hours in ethanol 95%.
Formalin fixation at low temperature better preserves nucleic acid integrity.
Specimen part
View SamplesAdult stem cells support tissue homeostasis and repair throughout the life of an individual. However, numerous intrinsic and extrinsic changes occur with age that result in altered stem cell behavior and reduced tissue maintenance and regeneration. In the Drosophila testis, stem cells surround and contact the apical hub, a cluster of somatic cells that express the self-renewal factor Unpaired (Upd), which activates the JAK-STAT pathway in adjacent stem cells. However, aging results in a dramatic decrease in upd expression, with a concomitant loss of germline stem cells (GSCs). Here we present genetic and biochemical data to demonstrate that IGF-II mRNA binding protein (Imp) counteracts endogenous small interfering RNAs to stabilize upd RNA and contribute to maintenance of the niche. However, Imp expression decreases in hub cells of older males, similar to upd, which is due to targeting of Imp by the heterochronic microRNA let-7. Therefore, in the absence of Imp, upd mRNA becomes unprotected and susceptible to degradation. Understanding the mechanistic basis for aging-related changes in stem cell behavior will lead to the development of strategies to treat age-onset diseases and facilitate stem cell based therapies in older individuals. Overall design: Examination of small RNA levels in testes from young (1day old) and aged (30days old) males of Drosophila melanogaster by deep sequencing (using Illumina GAII).
The let-7-Imp axis regulates ageing of the Drosophila testis stem-cell niche.
Specimen part, Cell line, Subject
View SamplesUsing a hitherto uncharacterized knockout mouse model of Notch 3, a Notch signaling receptor paralogue highly expressed in vascular SMCs, we uncover a striking susceptibility to ischemic stroke upon challenge. Cellular and molecular analyses of vascular SMCs derived from these animals associate Notch 3 activity to the expression of specific gene targets, whereas genetic rescue experiments unambiguously link Notch 3 function in vessels to the ischemic phenotype.
Notch signaling functions in retinal pericyte survival.
Sex, Specimen part
View SamplesNotch activation is instrumental in the development of most T-cell acute lymphoblastic leukemia (T-ALL) cases, yet Notch mutations alone are not sufficient to recapitulate the full human disease in animal models. We here found that Notch1 activation at the fetal liver (FL) stage expanded the hematopoietic progenitor population and conferred it transplantable leukemic-initiating capacity. However, leukemogenesis and leukemic-initiating cell capacity induced by Notch1 was critically dependent on the levels of ß-Catenin in both FL and adult bone marrow contexts. In addition, inhibition of ß-Catenin compromised survival and proliferation of human T-ALL cell lines carrying activated Notch1. By transcriptome analyses, we identified the MYC pathway as a crucial element downstream of ß-Catenin in these T-ALL cells and demonstrate that the MYC 3'' enhancer required ß-Catenin and Notch1 recruitment to induce transcription. Finally, PKF115-584 treatment prevented and partially reverted leukemogenesis induced by active Notch1. Overall design: Four T-ALL cell lines (RPMI8402, HPB-ALL, Jurkat, CCRF-CEM) were treated with DMSO (control) or PKF115-584 (310nM) for 3hrs. Gene expression changes were measured with Cufflinks comparing the 4 control with the 4 treated samples.
β-Catenin is required for T-cell leukemia initiation and MYC transcription downstream of Notch1.
No sample metadata fields
View SamplesEnvironmental enrichment has been shown to induce wholescale alterations to the gene expression profile of experimental animals
The impact of environmental enrichment on the murine inflammatory immune response.
Sex, Age
View SamplesTuberous Sclerosis Complex (TSC) is a disease caused by autosomal dominant mutations in the TSC1 or TSC2 genes, and is characterized by tumor susceptibility, brain lesions, seizures and behavioral impairments. The TSC1 and TSC2 genes encode proteins forming a complex (TSC), which is a major regulator and suppressor of mammalian target of rapamycin (mTOR) in complex 1 (mTORC1), a signaling complex that promotes cell growth and proliferation. TSC1/2 loss of heterozygosity (LOH) and the subsequent complete loss of TSC regulatory activity in null cells causes mTORC1 dysregulation and TSC-associated brain lesions or other tissue tumors. However, it is not clear whether TSC1/2 heterozygous brain cells are abnormal and contribute to TSC neuropathology. To investigate this issue, we generated induced pluripotent stem cells (iPSCs) from TSC patients and unaffected controls, and utilized these to obtain neural progenitor cells (NPCs) and differentiated neurons in vitro. These patient-derived TSC2 heterozygous NPCs were delayed in their ability to differentiate into neurons. Patient-derived progenitor cells also exhibited a modest activation of mTORC1 signaling downstream of TSC, and a marked attenuation of upstream PI3K/AKT signaling. We further show that pharmacologic AKT inhibition, but not mTORC1 inhibition, causes a neuronal differentiation delay, mimicking the patient phenotype. Together these data suggest that heterozygous TSC2 mutations disrupt neuronal development, potentially contributing to the disease neuropathology, and that this defect may result from dysregulated AKT signaling in neural progenitor cells. Overall design: Two replicates each of TSC#1 and CON#1 NPC cell RNA were prepared for sequencing library preparation and seqeuencing.
Neural progenitors derived from Tuberous Sclerosis Complex patients exhibit attenuated PI3K/AKT signaling and delayed neuronal differentiation.
Specimen part, Subject
View Samples