Transcriptomic study of breast angiosarcomas induced by radiotherapy using formalin-fixed paraffin (FFPE) embedded tissues
ABSTRACT: A transcriptome signature which discriminate efficiently primary and radiation induced breast angiosarcomas can be generated from FFPE tumor samples.FFPE samples are good material to unlock relevant informations from tumors. The transcriptome of 35 FFPE breast angiosarcomas (10 primary and 25 radiation induced) were analysed using Affymetrix Human Exon 1.0 ST arrays according to the FFPE dedicated protocole from NuGEN and compared to paired fresh frozen samples previously analysed. FF Samples are also available in Array Express as E-MEXP-3252.
Project description:This work focuses on understanding the molecular basis of the immune dysfunctions in Idiopathic CD4+ T cells lymphocytopenia (ICL). ICL is a rare haematological disorder of unknown origin, characterized by a profound and persistent CD4+ T-cell defect, which predisposes to life threatening opportunistic infections very similar to those seen in AIDS. To analyse more in depth the functional pathways involved in ICL pathogenesis, we conducted gene expression profiling of CD4+ T-cells isolated from blood samples from ICL, sarcoidosis and healthy individuals. Our analyses have revealed specific CD4+ T-cells gene expression signatures in ICL associated with defective TCR activation threshold, expansion of the Treg-cell compartment and interestingly with accelerated immune aging. 25 Total samples were analyzed. We generated the following pairwise comparisons using GenoSplice technology. We permormed multiple anlayses including : ICL vs Healthy (All or paired samples), ICL vs SARC (All or paired samples) and SARC vs Healthy (All or paired sample). Paired samples means that a same healthy individual was using in comparaison of a ICL or SARC subjects. Genes with a Fold-change ≥ 1,5 and P-Value ≤ 0,05 were selected.
Project description:Our purpose was to investigate genes and molecular mechanisms involved in patients with Leber congenital amaurosis (LCA). Fibroblasts from two unrelated clinically-identified patients (Coriell) were reprogrammed to pluripotency by retroviral transduction. These human induced Pluripotent Stem Cells (hiPSCs) were differentiated into neural stem cells (NSC) that mimicked the neural tube stage and retinal pigmented epithelial (RPE) cells that could be targeted by the disease. A genome wide transcriptome analysis was performed with Affymetrix Exon Array GeneChip®, comparing LCA-hiPSCs derivatives to controls. The aim was to identify differentially expressed genes which may be associated with early developmental defect before the establishment of mature retinal circuitry. We analyzed iPSC-derived retinal pigmented epithelial (RPE) cells from LCA patient's fibroblast (n=2) and iPSC-derivedretinal pigmented epithelial (RPE) cells from healthy people fibroblast (n=2). A total of 13 samples were analyzed : 9 RPE cells derived from iPSC LCA and 4 RPE cells derived from wild-type iPSC.
Project description:Our purpose was to investigate genes and molecular mechanisms involved in patients with Leber congenital amaurosis (LCA). Fibroblasts from two unrelated clinically-identified patients (Coriell) were reprogrammed to pluripotency by retroviral transduction. These human induced Pluripotent Stem Cells (hiPSCs) were differentiated into neural stem cells (NSC) that mimicked the neural tube stage and retinal pigmented epithelial (RPE) cells that could be targeted by the disease. A genome wide transcriptome analysis was performed with Affymetrix Exon Array GeneChip®, comparing LCA-hiPSCs derivatives to controls. The aim was to identify differentially expressed genes which may be associated with early developmental defect before the establishment of mature retinal circuitry. We analyzed iPSC-derived neural stem cells from LCA patient's fibroblast (n=2) and iPSC-derived neural stem cells from healthy people fibroblast (n=2). A total of 21 samples were analyzed : 9 NSC derived from iPSC LCA and 12 NSC derived from wild-type iPSC.
Project description:Stringent regulation of the interferon signaling pathway is essential for maintaining the immune response to pathogens and tumors. The transcription factor STAT1 is a crucial mediator of this response. Here we show that hCAF1/CNOT7 regulates class I and II interferon pathways at different crucial steps. In resting cells hCAF1 can control STAT1 trafficking by interacting with the latent form of STAT1 in the cytoplasm. IFN treatment induces STAT1 release, suggesting that hCAF1 may shield cytoplasmic STAT1 from undesirable stimulation. Consistent, hCAF1 silencing enhances STAT1 basal promoter occupancy associated with increased expression of a subset of STAT1-regulated genes. Consequently, hCAF1 knockdown cells exhibit an increased protection against viral infection and reduced viral replication. Furthermore, hCAF1 participates in the extinction of the IFN signal, through its deadenylase activity, by speeding up the degradation of some STAT1-regulated mRNAs. Since abnormal and unbalanced JAK/STAT activation is associated with immune disorders and cancer, hCAF1 could play a major role in innate immunity and oncogenesis, contributing to tumor escape. mRNAs from cells expressing the siRNA siRNA duplexes targeting hCAF1, corresponding to the coding region 941-961 (kd) (hCAF1 NCBI Reference Sequence: NM_013354.5) and one non-targeting control siRNA (mock).
Project description:By using patient-derived xenografts (PDXs) as living surrogate of the clinical practice, we identify here induction of genes related to the IFN pathway as an early and specific predictor of tumor response to treatment. Gene expression profile of tumor cells after laser-capture microdissection of residual tumor foci to characterize the molecular changes occurring in residual tumor cells surviving chemotherapy RNA was extracted from microdissected areas using the RNeasy Mini kit (Qiagen, Valencia, CA). This approach allowed isolating foci of human tumor cells from the murine stroma. Gene expression analysis was performed with Affymetrix Exon 1.0 ST microarrays. Hybridization, data normalization and statistical analysis were outsourced to GenoSplice Technology (Paris, France).
Project description:Summary: Melanoma spheroids grown under neural crest cell conditions are highly plastic migratory/invasive tumor cells endowed with immunomodulator function Background: The aggressiveness of melanoma tumors is likely to rely on their well-recognized heterogeneity and plasticity. Melanoma comprises multi subpopulations of cancer cells some of which may possess stem cell-like properties supporting the notion of plasticity. Although useful for certain tumors, the use of the sphere-formation assay to identify stem cell-like or tumor initiating cells subpopulations in human melanoma has been recently challenged. Our study reveals that this assay predicts a functional phenotype associated with aggressive behavior of tumor cells. Methodology/Principal Findings: We analyzed the molecular and functional phenotypes of melanoma spheroids formed in neural crest cell medium. Whether from metastatic (SLM8) or advanced primary (Mela1) tumors, spheroid cells expressed melanoma-associated markers. They displayed higher capacity to differentiate along mesenchymal lineages, and showed enhanced expression of SOX2, NANOG, KLF4, and/or OCT4 transcription factors, but not extensive self-renewal or enhanced tumorigenicity when compared to their adherent counterparts. To determine whether melanoma spheroids in our model could predict a molecular or functional phenotype, we performed gene expression profiling experiments using Affymetrix microarrays. Gene expression profiling attributed a neural crest cell signature to these spheroids and indicated that a migratory/invasive and immune-function modulating program could be associated with these cells. In vitro assays confirmed that these spheroids are endowed with enhanced migratory/invasive capacities. In immune activation assays, spheroid cells elicited a poorer allogenic response from immune cells and inhibited mitogen-dependent T cells activation and proliferation more efficiently than their adherent counterparts. Thus, our findings reveal novel immune-modulator function of melanoma spheroid cells and suggest specific roles for these spheroids in invasion and in evasion of antitumor immunity. Conclusion/Significance: The association of a more plastic, invasive and evasive, thus a more aggressive tumor phenotype with melanoma spheroid cells reveals a previously unrecognized aspect of tumor cells expanded as spheroid cultures. While of limited efficiency for melanoma initiating cell identification, our melanoma spheroid model predicted aggressive phenotype and could therefore, be constructive to investigate melanoma aggressiveness, relevant to patients and clinical transferability. 12 Total samples were analyzed: SLM8 adherent (SLMA) and spheroids (SLMS) cells, and Mela1 adherent (MelaA) and spheroid (MelaS) cells, all performed in triplicates. Paired statistical analyses were performed using Student's paired t-test on the gene signal intensities (gene level) and results were considered statistically significant at p-values <=0.05 and fold-change >=1.5.
Project description:We generated a HeLa cell model of mucopolysaccharidosis IIIB (MPSIIIB) by depleting NAGLU. MPSIIIB-associated cell defects were prominent in NAGLU-depleted cells. We explored alterations of metabolic pathways in NAGLU-depleted cells versus non-depleted control cells by performing gene expression profiling. Exon array transcriptome analysis showed 96 transcripts with increased expression level and 38 transcripts with decreased expression level in NAGLU-depleted versus non-depleted cells. Total RNA was extracted from two independent cultures of non-depleted cells and NAGLU-depleted cells. We considered a minimal fold change of 1.5 fold and a corrected P value lower than 0.05.
Project description:Transcriptome analysis of depletion of DYRK1A in HeLa cells Global gene expression profiling has shown upregulation of many genes in the context of DYRK1A depletion in HeLa cells. Many of these genes deregulated by DYRK1A are involved in immune response system. Transcriptome analysis of siRNA against DYRK1A transfected in HeLa cells on GeneChip® Human Exon 1.0 ST Arrays (Affimetrix). Control HeLa cells have been transfected with the same concentration of siRNA non-targeting (siNT). Experiment has been done experimental triplicates.
Project description:We generated iPSc from skin fibroblasts of two MPSIIIB patients (P1 and P2). MPSIIIB-associated cell defects were prominent in undifferentiated iPSc, in neural stem cells and in their neuronal progeny. We explored alterations of metabolic pathways in MPSIIIB neural cells by performing gene expression profiling of patient versus control neural stem cells. Exon array transcriptome analysis showed 295 transcripts with increased expression level and 1275 transcripts with decreased expression level in patient versus control neural precursors. Total RNA was extracted from proliferating neurosphere cultures derived from two control (C1 and C3) and three patient (P1.1, P1.3, and P2.3) iPSc clones. We considered a minimal fold change of 1.5 fold and a corrected P value lower than 0.05.