This SuperSeries is composed of the SubSeries listed below.
A post-transcriptional program of chemoresistance by AU-rich elements and TTP in quiescent leukemic cells.
Specimen part, Cell line, Treatment
View SamplesQuiescence (G0) is a transient, cell cycle-arrested state. By entering G0, cancer cells survive unfavorable conditions such as chemotherapy and cause relapse. While G0 cells have been studied at the transcriptome level, how post-transcriptional regulation contributes to their chemoresistance remains unknown. We induced chemoresistant and quiescent (G0) leukemic cells by serum-starvation or chemotherapy treatment. To study post-transcriptional regulation in G0 leukemic cells, we systematically analyzed their transcriptome, translatome, and proteome. We find that our resistant G0 cells recapitulate gene expression profiles of in vivo chemoresistant leukemic and G0 models. In G0 cells, canonical translation initiation is inhibited; yet we find that inflammatory genes are highly translated, indicating alternative post-transcriptional regulation. Importantly, AU-rich elements (AREs) are significantly enriched in the up-regulated G0 translatome and transcriptome. Mechanistically, we find the stress-responsive p38 MAPK-MK2 signaling pathway stabilizes ARE mRNAs by phosphorylation and inactivation of mRNA decay factor, tristetraprolin (TTP) in G0. This permits expression of ARE mRNAs that promote chemoresistance. Conversely, inhibition of TTP phosphorylation by p38 MAPK inhibitors and non-phosphorylatable TTP mutant decreases ARE-bearing TNFα and DUSP1 mRNAs and sensitizes leukemic cells to chemotherapy. Furthermore, co-inhibiting p38 MAPK and TNFα—prior to or along with chemotherapy—substantially reduced chemoresistance in primary leukemic cells ex vivo and in vivo. These studies uncover post-transcriptional regulation underlying chemoresistance in leukemia. Our data reveal the p38 MAPK-MK2-TTP axis as a key regulator of expression of ARE bearing mRNAs that promote chemoresistance. By disrupting this pathway, we developed an effective combination therapy against chemosurvival.
A post-transcriptional program of chemoresistance by AU-rich elements and TTP in quiescent leukemic cells.
Cell line, Treatment
View SamplesQuiescence (G0) is a transient, cell cycle-arrested state. By entering G0, cancer cells survive unfavorable conditions such as chemotherapy and cause relapse. While G0 cells have been studied at the transcriptome level, how post-transcriptional regulation contributes to their chemoresistance remains unknown. We induced chemoresistant and quiescent (G0) leukemic cells by serum-starvation or chemotherapy treatment. To study post-transcriptional regulation in G0 leukemic cells, we systematically analyzed their transcriptome, translatome, and proteome. We find that our resistant G0 cells recapitulate gene expression profiles of in vivo chemoresistant leukemic and G0 models. In G0 cells, canonical translation initiation is inhibited; yet we find that inflammatory genes are highly translated, indicating alternative post-transcriptional regulation. Importantly, AU-rich elements (AREs) are significantly enriched in the up-regulated G0 translatome and transcriptome. Mechanistically, we find the stress-responsive p38 MAPK-MK2 signaling pathway stabilizes ARE mRNAs by phosphorylation and inactivation of mRNA decay factor, tristetraprolin (TTP) in G0. This permits expression of ARE mRNAs that promote chemoresistance. Conversely, inhibition of TTP phosphorylation by p38 MAPK inhibitors and non-phosphorylatable TTP mutant decreases ARE-bearing TNFα and DUSP1 mRNAs and sensitizes leukemic cells to chemotherapy. Furthermore, co-inhibiting p38 MAPK and TNFα—prior to or along with chemotherapy—substantially reduced chemoresistance in primary leukemic cells ex vivo and in vivo. These studies uncover post-transcriptional regulation underlying chemoresistance in leukemia. Our data reveal the p38 MAPK-MK2-TTP axis as a key regulator of expression of ARE bearing mRNAs that promote chemoresistance. By disrupting this pathway, we developed an effective combination therapy against chemosurvival.
A post-transcriptional program of chemoresistance by AU-rich elements and TTP in quiescent leukemic cells.
Specimen part, Treatment
View SamplesPuberty unmasks or accelerates nephropathies, including the nephropathy of diabetes mellitus (DM). A number of cellular systems implicated in the kidney disease of DM interweave, forming an interdependent functional web. We performed focused microarray analysis to test the hypothesis that one or more genes in the transforming growth factor beta (TGF-) signaling system would be differentially regulated in male rats depending on the age of onset of DM.
Prepubertal onset of diabetes prevents expression of renal cortical connective tissue growth factor.
No sample metadata fields
View SamplesCircadian rhythm study on transcriptional responses to i.v. administered 90 kBq iodine-131 after 24h in mouse kidney cortex and medulla, liver, lungs, spleen, and thyroid.
Circadian rhythm influences genome-wide transcriptional responses to (131)I in a tissue-specific manner in mice.
Sex, Specimen part, Time
View SamplesTo understand the interplay between cancer and stroma, we performed single cell RNA-sequencing of PDAC cells admixed with stromal fibroblasts and defined different single cell populations with varying levels of proliferative and metastatic transcriptional states. PDAC cell behavior in vitro and in vivo on these phenotypic axes could be tuned with the proportion of stromal fibroblasts. These cell types were identified in human pancreatic tumors, and specific subpopulations were associated with worsened outcomes. Overall design: 92 single PDAC cells and 92 single CAF cells were micromanipulated and prepared for sequencing (23 of each cell type from four culture ratios). The 24th sample from each cell type-culture condition combination is a population control obtained by micromanipulating 100 cells of the given type from the given culture condition and preparing it as if it were a single cell, giving a total of 96 PDAC samples and 96 CAF samples. During the course of library construction, 3 samples were lost, all PDAC cells from the 30:70 condition (two single cells and the population control), leaving 93 total PDAC samples and 96 total CAF samples.
Stromal Microenvironment Shapes the Intratumoral Architecture of Pancreatic Cancer.
Specimen part, Subject
View SamplesThe mammary gland is a highly dynamic organ that mainly develops during puberty. Based on morphology and proliferation analysis, mammary stem cells (MaSCs) are thought to be close to or reside in the terminal end buds (TEBs) during pubertal development. However, exclusive stem cell markers are lacking, and therefore the true identity of MaSCs, including their location, multiplicity, dynamics and fate during branching morphogenesis, has yet to be defined. To gain more insights into the molecular identity and heterogeneity of the MaSC pool, we performed single cell transcriptome sequencing of mammary epithelial cells micro-dissected from ducts and TEBs during puberty. These data show that the behaviour of MaSCs cannot be directly linked to a single expression profile. Instead, morphogenesis of the mammary epithelium relies upon a heterogeneous population of MaSCs that functions long-term as a single equipotent pool of stem cells. Overall design: Ducts and terminal end buds were micro-dissected from the 4th and the 5th murine mammary gland at 5 weeks-of-age, dissociated into single cells, and FACS sorted. Single-cell transcriptomics was performed on live cells using an automated version of CEL-seq2 on live, FACS sorted cells. The StemID algorithm was used to identify clusters of cells corresponding to basal and luminal cells types derived from ducts and terminal end buds.
Identity and dynamics of mammary stem cells during branching morphogenesis.
Cell line, Subject
View SamplesProgesterone promotes differentiation coupled to proliferation and pro-survival in the breast, but inhibits estrogen-driven growth in the reproductive tract and ovaries. Herein, it is demonstrated, using progesterone receptor (PR) isoform-specific ovarian cancer model systems, that PR-A and PR-B promote distinct gene expression profiles that differ from PR-driven genes in breast cancer cells. In ovarian cancer models, PR-A primarily regulates genes independently of progestin, while PR-B is the dominant ligand-dependent isoform. Notably, FOXO1 and the PR/FOXO1 target-gene p21 (CDKN1A) are repressed by PR-A, but induced by PR-B. In the presence of progestin, PR-B, but not PR-A, robustly induced cellular senescence via FOXO1-dependent induction of p21 and p15 (CDKN2B). Chromatin immunoprecipitation (ChIP) assays performed on PR-isoform specific cells demonstrated that while each isoform is recruited to the same PRE-containing region of the p21 promoter in response to progestin, only PR-B elicits active chromatin marks. Overexpression of constitutively active FOXO1 in PR-A-expressing cells conferred robust ligand-dependent upregulation of the PR-B target genes GZMA, IGFBP1, and p21, and induced cellular senescence. In the presence of endogenous active FOXO1, PR-A was phosphorylated on Ser294 and transactivated PR-B at PR-B target genes; these events were blocked by the FOXO1 inhibitor (AS1842856). PR isoform-specific regulation of the FOXO1/p21 axis recapitulated in human primary ovarian tumor explants treated with progestin; loss of progestin sensitivity correlated with high AKT activity.
Active FOXO1 Is a Key Determinant of Isoform-Specific Progesterone Receptor Transactivation and Senescence Programming.
Treatment, Time
View SamplesProgesterone receptors (PRs) are critical context-dependent transcription factors required for normal uterine (PR-A) and mammary gland (PR-B) development. Progesterone is proliferative in the breast, where PR-target genes include paracrine factors that mediate mammary stem cell self-renewal. In the context of altered signal transduction that typifies breast tumorigenesis, dysregulated (i.e. hyper-phosphorylated) PRs likely contribute to tumor progression by promoting cancer cell pro-survival and proliferation. Notably, in breast cancer cells, progestin-bound PRs induce rapid MAPK activation leading to selective regulation of growth-promoting genes by phosphorylated PR species. Functional domains within PR that interact with c-Src and estrogen receptors (ER) have been identified as indirect routes to MAPK activation. Herein, we describe a common docking (CD) domain located within the PR-B N-terminus, a motif first described in MAPKs that facilitates direct interactions between MAPKs and MEK1 or MAPK-phosphatases (MKPs). Mutation of negatively-charged amino acids, previously determined to be critical for CD domain function in MAPKs, within PR-B (mCD PR) did not alter MEK-binding or progestin-induced rapid signaling (i.e. MAPK activation) and PR transcriptional activity as measured by PRE-luciferase (reporter) assays. Microarray gene-expression analysis revealed that endogenous genes regulated by wt PR, but not mCD PR, are involved in critical cellular pathways regulating growth, proliferation, survival, and cancer. mCD PR failed to undergo ligand-induced phosphorylation on Ser81, a ck2-dependent site required for progestin-regulation of select growth-promoting genes (BIRC3, HSD112, HbEGF). Progestin-induced PR Ser81 phosphorylation mapped to CD domain-dependent binding of PR-B to MKP3, but did not require phosphatase activity. Receptors containing either mutant CD domains (mCD PR) or point mutations of Ser81 (S79/81A PR) failed to upregulate STAT5 and Wnt1, key PR-target gene products that act as critical mediators of mammary stem cell expansion. Inhibition of JAK/STAT signaling blocked progestin-induced STAT5 and Wnt1 expression. ChIP assays demonstrated that wt, but not phospho-mutant (S79/81A), PR-B was co-recruited to a PRE-containing enhancer region of the Wnt1 gene along with MKP3, ck2 and STAT5. Our studies reveal a novel scaffolding action of MKP3 mediated by interaction with the PR CD domain and required for ck2-dependent PR Ser81 phosphorylation. Co-regulation of select target genes by phospho-Ser81 PR and phospho-STAT5 is likely a global mechanism required for the activation of growth promoting programs active during normal mammary gland development and relevant to mechanisms of breast cancer progression.
A Common Docking Domain in Progesterone Receptor-B links DUSP6 and CK2 signaling to proliferative transcriptional programs in breast cancer cells.
Specimen part, Treatment
View SamplesThe progesterone receptor specific gene targets were investigated in ovarian and breast cancer cell lines where FOXO1 was found to be a primary factor that cooperates with PR to activate cellular senescence genes (including p21) specifically in ovarian cells.
Active FOXO1 Is a Key Determinant of Isoform-Specific Progesterone Receptor Transactivation and Senescence Programming.
Treatment, Time
View Samples