Our understanding of cellular mechanisms by which animals regulate their response to starvation is limited despite the close relevance of the problem to major human health issues. L1 diapause of Caenorhabditis elegans, where newly hatched first stage larval arrested in response to food-less environment, is an excellent system to study the problem. We found through genetic manipulation and lipid analysis that ceramide biosynthesis, particularly those with longer fatty acid side chains, critically impacts animal survival during L1 diapause. Genetic and expression analyses indicate that ceramide likely regulate this response by affecting gene expression and activity in multiple regulatory pathways known to regulate starvation-induced stress, including the insulin-IGF-1 signaling (IIS) pathway, Rb and other pathways that mediate pathogen/toxin/oxidative stress responses. These findings provide an important insight into the roles of sphingolipid metabolism in not only starvation response but also aging and food-response related human health problems.
Starvation-Induced Stress Response Is Critically Impacted by Ceramide Levels in Caenorhabditis elegans.
No sample metadata fields
View SamplesEndothelial cells (ECs) express two members of the cadherin family, VE- and N-cadherin. While VE-cadherin induces EC homotypic adhesion, N-cadherin function in ECs remains largely unknown. EC-specific inactivation of either VE- or N-cadherin leads to early foetal lethality suggesting that these cadherins play a non-redundant role in vascular development.
Overlapping and divergent signaling pathways of N-cadherin and VE-cadherin in endothelial cells.
Specimen part, Cell line
View SamplesTo investigate the molecular bases of diet induced differences in milk composition, we collected milk from mid lactation dairy ewes and after 3 weeks of diet supplementation with extruded linseed. RNAs were isolated from milk somatic cells isolated from milk of 3 sheep and Illumina RNA sequencing was performed to analyze RNA synthesis in these cells. Overall design: Transcriptional profiling of milk somatic cells of sheep fed with normal diet and with a supplementation with extruded linseed. Sequence data were generated by deep sequencing, on three replicates, using Illumina HiSeq2000.
Transcript profiling in the milk of dairy ewes fed extruded linseed.
Specimen part, Subject
View SamplesThe biological features of ovarian cancer stem cells (OCSC) remain elusive, mainly because 1) most studies so far have focused on cell lines that recapitulate the human disease only to a limited extend; and 2) because the identification of OCSC has relied on markers inferred from different and unrelated tumor types. Our study has harnessed the intrinsic, stemness-related properties of OCSC to identify and isolate this cell subpopulation from primary cultures freshly established from high-grade serous ovarian cancer (HGSOC), the most common and aggressive from of the disease. In addition, OCSC were compared to stem cell-enriched cultures from fallopian tube epithelium, which is the most accredited tissue of origin for HGSOC. The transcriptomes of the two cell types were compared to infer genes differentially regulated in OCSC.
CD73 Regulates Stemness and Epithelial-Mesenchymal Transition in Ovarian Cancer-Initiating Cells.
Specimen part
View SamplesPrimary effusion lymphoma is an aggressive B-cell lymphoma most commonly diagnosed in HIV-positive patients and universally associated with Kaposis sarcoma-associated herpesvirus (KSHV). Chemotherapy treatment of PEL yields only short-term remissions in the vast majority of patients yet efforts to develop superior therapeutic approaches have been impeded by lack of animal models that more accurately mimic human disease. To address this issue we developed a direct xenograft model, UM-PEL-1, by transferring freshly-isolated human PEL cells into the peritoneal cavities of NOD/SCID mice without in vitro cell growth. We utilized this model to show that bortezomib induces PEL remission and extends overall survival of mice bearing lymphomatous effusions. Transcriptome analysis by genomic arrays revealed that bortezomib downregulated cell cycle progression, DNA replication, and Myc-target genes.
Efficacy of bortezomib in a direct xenograft model of primary effusion lymphoma.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrated molecular analysis of Tamoxifen-resistant invasive lobular breast cancer cells identifies MAPK and GRM/mGluR signaling as therapeutic vulnerabilities.
Treatment
View SamplesInvasive lobular breast cancer (ILC) is an understudied malignancy with distinct clinical, pathological, and molecular features that distinguish it from the more common invasive ductal carcinoma (IDC). Mounting evidence suggests that estrogen receptor-alpha positive (ER+) ILC has a poor response to Tamoxifen (TAM), but the mechanistic drivers of this are undefined. In the current work, we comprehensively characterize the SUM44/LCCTam ILC model system through integrated analysis of gene expression, copy number, and mutation, with the goal of identifying actionable alterations relevant to clinical ILC that can be co-targeted along with ER to improve treatment outcomes. We show that TAM has several distinct effects on the transcriptome of LCCTam cells, that this resistant cell model has acquired copy number alterations and mutations that impinge on MAPK and metabotropic glutamate receptor (GRM/mGluR) signaling networks, and that pharmacological inhibition of either improves or restores the growth-inhibitory actions of endocrine therapy.
Integrated molecular analysis of Tamoxifen-resistant invasive lobular breast cancer cells identifies MAPK and GRM/mGluR signaling as therapeutic vulnerabilities.
Treatment
View SamplesOne-third of all ER+ breast tumors treated with endocrine therapy fail to respond, and the remainder are likely to relapse in the future. Almost all data on endocrine resistance has been obtained in models of invasive ductal carcinoma (IDC). However, invasive lobular carcinomas (ILC) comprise up to 15% of newly diagnosed invasive breast cancers diagnosed each year and, while the incidence of IDC has remained relatively constant during the last 20 years, the prevalence of ILC continues to increase among postmenopausal women. We report a new model of Tamoxifen (TAM)-resistant invasive lobular breast carcinoma cells that provides novel insights into the molecular mechanisms of endocrine resistance. SUM44 cells express ER and are sensitive to the growth inhibitory effects of antiestrogens. Selection for resistance to 4-hydroxytamoxifen led to the development of the SUM44/LCCTam cell line, which exhibits decreased expression of estrogen receptor alpha (ER) and increased expression of the estrogen-related receptor gamma (ERR). Knockdown of ERR in SUM44/LCCTam cells by siRNA restores TAM sensitivity, and overexpression of ERR blocks the growth-inhibitory effects of TAM in SUM44 and MDA-MB-134 VI lobular breast cancer cells. ERR-driven transcription is also increased in SUM44/LCCTam, and inhibition of activator protein 1 (AP1) can restore or enhance TAM sensitivity. These data support a role for ERR/AP1 signaling in the development of TAM resistance, and suggest that expression of ERR may be a marker of poor Tamoxifen response.
ERRgamma mediates tamoxifen resistance in novel models of invasive lobular breast cancer.
No sample metadata fields
View SamplesIn an attempt to elucidate the molecular mechanisms underlying the multiple roles of L1 in endothelium, we checked whether manipulating its expression affected the transcriptome of lECs. To this purpose, we compared the gene expression profiles of L1-overexpressing and control lECs by Affymetrix, which revealed a remarkable effect of L1 overexpression on lECs transcriptome.
Endothelial deficiency of L1 reduces tumor angiogenesis and promotes vessel normalization.
Specimen part
View SamplesTransfection of a Kaposi's sarcoma (KS) herpesvirus (KSHV) Bacterial Artificial Chromosome (KSHVBac36) into mouse bone marrow endothelial lineage cells generated a cell (mECK36) that induced KS-like tumors in mice. mECK36 formed KSHV-harboring vascularized spindle-cell sarcomas that were LANA+ and displayed a KSHV and host transcriptomes reminiscent of KS tumors.
In vivo-restricted and reversible malignancy induced by human herpesvirus-8 KSHV: a cell and animal model of virally induced Kaposi's sarcoma.
No sample metadata fields
View Samples