The biology underlying nodal metastasis is poorly understood. Transcriptome profiling has helped to characterize both primary tumors seeding nodal metastasis and the metastasis themselves. The interpretation of these data, however, is not without ambiguities. Here we profiled the transcriptomes of 17 papillary thyroid cancer (PTC) nodal metastases, associated primary tumors and primary tumors from N0 patients. We also included patient-matched normal thyroid and lymph node samples as controls to address some limits of previous studies. We found that the transcriptomes of patient-matched primary tumors and metastases were more similar than of unrelated metastases/primary pairs, a result also reported in other organ systems, and that part of this similarity reflected patient background. We found that the comparison of patient-matched primary tumors and metastases was heavily confounded by the presence of lymphoid tissues in the metastasis samples. An original data adjustment procedure was developed to circumvent this problem. It revealed a differential expression of stroma-related gene expression signatures also regulated in other organ systems. The comparison of N0 vs. N+ primary tumors uncovered a signal irreproducible across independent PTC datasets. This signal was also detectable when comparing the normal thyroid tissues adjacent to N0 and N+ tumors, suggesting a cohort specific bias also likely to be present in previous studies with similar statistical power. Classification of N0 vs. N+ yielded an accuracy of 63%, but additional statistical controls not presented in previous studies, revealed that this is likely to occur by chance alone. To address this issue, we used large datasets from The Cancer Genome Atlas and showed that N0 vs. N+ classification rates could not be reached randomly for most cancers. Yet, it was significant, but of limited accuracy (<70%) for thyroid, breast and head and neck cancers.
Revisiting the transcriptional analysis of primary tumours and associated nodal metastases with enhanced biological and statistical controls: application to thyroid cancer.
Sex
View SamplesRadiation is an established cause of thyroid cancer and growing evidence supports a role for H2O2 in spontaneous thyroid carcinogenesis. Little is known about the molecular programs activated by these agents in thyroid cells. We profiled the DNA damage response and cell death induced by -radiation (0.15Gy) and H2O2 (0.00250.3mM) in primary human thyroid cells and T-cells. While the two cell types had more comparable radiation responses, 3- to 10-fold more H2O2 was needed to induce detectable DNA damage in thyrocytes. At H2O2 and radiation doses incurring double-strand breaks (DSB), cell death occurred after 24hrs in T-cells, but not in thyrocytes. We next prepared thyroid and T-cells primary cultures from 8 donors operated for non-cancerous pathologies and profiled their genome-wide transcriptional response 4hr after: 1) exposure to 1 Gy radiation, 2) treatment with H2O2, or 3) no treatment. Two H2O2 doses were investigated, calibrated in each cell type as to elicit levels of single- and double-strand breaks equivalent to 1 Gy -radiation. The transcriptional responses of thyrocyte and T-cells to radiation were similar, involving DNA repair and cell death genes. In addition to this transcriptional program, H2O2 also upregulated antioxidant genes in thyrocytes, including glutathione peroxidases (GPx) at the DSB-inducing dose. By contrast, a transcriptional storm involving thousands of genes was raised in T-cells. Finally, we showed that GPx inhibition reduced the DNA damaging effect of H2O2 in thyrocytes. We conjecture that defects of anti- H2O2 protection could promote spontaneous thyroid cancers.
Comparative analysis of the thyrocytes and T cells: responses to H2O2 and radiation reveals an H2O2-induced antioxidant transcriptional program in thyrocytes.
Sex, Age, Treatment, Subject
View SamplesThe RET/PTC3 (RP3) fusion gene is the most frequent mutation found in radiation-induced papillary thyroid cancers (PTC). Several studies suggest that the RET/PTC rearrangement is an initiating event in tumorigenesis. E7 is an oncoprotein derived from the Human Papilllomavirus 16 (HPV16) responsible for most cervical carcinoma in women. We studied here the sequence of events leading to thyroid cancer in Tg-RP3 and Tg-E7 mice expressing the transgene exclusively in the thyroid under the control of thyroglobulin (Tg) promoter. Both transgenic mice develop thyroid hyperplasia followed by solid differentiated carcinoma in older animals. To understand the different steps leading to carcinoma, we analyzed thyroid gene expression in both strains at different ages (2, 6, 10 months) by microarray technology. Important biological processes were differentially regulated in the two tumor types. In E7 thyroids cell cycle was the most upregulated process; observation consistent with the huge size of these tumors. In RP3 thyroids immunity was the most significantly regulated process, as previously observed in microarray data on human PTC. Interestingly, other human PTC characteristics were also observed in RP3 but not in E7 mouse tumors: similar regulation of several human PTC markers, upregulation of many EGF-like growth factors and finally significant regulation of angiogenesis and extracellular matrix remodeling-related genes. In summary we showed that RP3 contrary to E7 mouse tumors share several important genotypic characteristics with human PTC, observation reinforcing the validity of this model to study human thyroid tumorigenesis.
Gene expression in RET/PTC3 and E7 transgenic mouse thyroids: RET/PTC3 but not E7 tumors are partial and transient models of human papillary thyroid cancers.
No sample metadata fields
View SamplesWe profiled the gene expression of 11 anaplastic thyroid carcinomas (ATC), 49 papillary thyroid carcinomas (PTC) and 45 normal thyroids (N)
A general method to derive robust organ-specific gene expression-based differentiation indices: application to thyroid cancer diagnostic.
Specimen part
View SamplesThe cerebral cortex underwent a rapid expansion and complexification during recent primate evolution, but the underlying developmental mechanisms remain essentially unknown.
Genes expressed in specific areas of the human fetal cerebral cortex display distinct patterns of evolution.
Age, Specimen part
View SamplesMicroarrays have revolutionized breast cancer (BC) research by enabling studies of gene expression on a transcriptome-wide scale. Recently, RNA-Sequencing (RNA-Seq) has emerged as an alternative for precise readouts of the transcriptome. To date, no study has compared the ability of the two technologies to quantify clinically relevant individual genes and microarray-derived gene expression signatures (GES) in a set of BC samples encompassing the known molecular BC's subtypes. To accomplish this, the RNA from 57 BCs representing the four main molecular subtypes (triple negative, HER2 positive, luminal A, luminal B), was profiled with Affymetrix HG-U133 Plus 2.0 chips and sequenced using the Illumina HiSeq 2000 platform. The correlations of three clinically relevant BC genes, six molecular subtype classifiers, and a selection of 21 GES were evaluated.
Transfer of clinically relevant gene expression signatures in breast cancer: from Affymetrix microarray to Illumina RNA-Sequencing technology.
Specimen part, Disease stage
View SamplesThyroid gland is among the most sensitive organs to ionizing radiation. Whether low-dose radiation-induced papillary thyroid cancer (PTC) differs from sporadic PTC is yet unknown.
Gene signature of the post-Chernobyl papillary thyroid cancer.
No sample metadata fields
View SamplesThe goal of this study was to identify the transcriptional mechanisms involved in the activation of the immune system by QS-21, a triterpene glycoside purified from the bark of Quillaja saponaria which has adjuvant activity in vivo. Saponins represent a promising class of vaccine adjuvant. Together with the TLR4-ligand MPL, QS-21 is part of the Adjuvant System AS01, a key component of the Malaria and Zoster candidate vaccines that display demonstrated clinical efficacy. However, the mechanism of action of QS-21 in this liposomal formulation is poorly understood. Upon intra-muscular immunisation, we observed that QS-21 rapidly accumulated in CD169+ resident macrophages of the draining lymph node where it elicited a local innate immune response. Depletion of these cells abrogated QS-21-mediated innate cell recruitment to the lymph node, dendritic cell (DC) phenotypic maturation as well as the adjuvant effect on T cell and antibody responses to co-administered antigens. DCs rather than lymph node-resident macrophages were directly involved in T cell priming by QS-21 as revealed by the decrease in antigen-specific T cell response in Batf3/ mice. Further analysis showed that the adjuvant effect of QS-21 depended on the integration of Caspase-1 and MyD88 pathways, at least in part through the local release of HMGB1. Taken together, this work unravels the key role of lymph node sentinel macrophage in controlling the adjuvant effect of a molecule proven to improve vaccine response in humans
Central Role of CD169<sup>+</sup> Lymph Node Resident Macrophages in the Adjuvanticity of the QS-21 Component of AS01.
Specimen part
View SamplesWe established gene expression profiles of diagnostic bone marrow samples of monozygotic twins with acute lymphoblastic leukemia. We established technical duplicates for each twin.
Prenatal origin of separate evolution of leukemia in identical twins.
Sex, Specimen part, Disease, Disease stage
View SamplesWe sequenced liver mRNA from 23 individual pigs (5 prefed and 18 fasted) taken at 4 separate time points to evaluate the change in gene expression over the course of hemorrhagic shock and resuscitation in response to a carbohydrate prefed state. Overall design: Examination of mRNA levels in liver biopsies from pigs at 4 timepoints throughout hemorrhagic shock and resuscitation
Fed state prior to hemorrhagic shock and polytrauma in a porcine model results in altered liver transcriptomic response.
Specimen part, Cell line, Subject, Time
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