Silver nanoparticles are used in consumer products like food contact materials, drinking water technologies and supplements, due to their antimicrobial properties. This leads to an oral uptake and exposure of intestinal cells. In contrast to other studies we found no apoptosis induction by surfactant coated silver nanoparticles in the intestinal cell model Caco-2 in a previous study, although the particles induced oxidative stress, morphological changes and cell death. Therefore, this study aimed to analyze the molecular mechanism of silver nanoparticles in Caco-2 cells. We used global gene expression profiling in differentiated Caco-2 cells, supported by verification of the microarray data by quantitative real time RT-PCR and microscopic analysis, impedance measurements and assays for apoptosis and oxidative stress. Our results revealed that the majority of surfactant coated silver nanoparticles are not taken up into differentiated Caco-2 cells. and probably affect the cells by outside-in signaling. They induce oxidative stress and have an influence on canonical pathways related to FAK, ILK, ERK, MAPK, integrins and adherence and tight junctions, thereby inducing transcription factors like AP1, NFB and NRF2, which mediate cellular reactions in response to oxidative stress and metal ions and induce changes in the cytoskeleton and cell-cell and cell-matrix contacts. The present data confirm the absence of apoptotic cell death. Non-apoptotic, necrotic cell death, especially in the intestine, can cause inflammation and influence the mucosal immune response.
Molecular mechanism of silver nanoparticles in human intestinal cells.
Cell line
View SamplesThis study provides the first comprehensive analysis of gene expression and transcriptome dynamics of bovine metaphase II oocytes and in vivo developing bovine embryos.
Genome-wide expression profiling reveals distinct clusters of transcriptional regulation during bovine preimplantation development in vivo.
No sample metadata fields
View SamplesAdam10, a cell surface protease, cleaving many proteins including TNF-alpha and E-cadherin. Here we investigate the genome wide effects of Adam10 knock out on the transcriptome.
The disintegrin/metalloproteinase Adam10 is essential for epidermal integrity and Notch-mediated signaling.
Specimen part
View SamplesThis study explores the underlying pathogenic mechanisms of congenital intrinsic obstruction of the ureteropelvic junction. A hedgehog-dependent mechanism underlying mammalin intrinsic ureteropelvic obstruction is defined. Overall design: Tissue was microdissected from the kidney-ureter junction at E13.5, one day after the onset of Ptc2-lacZ expression, from PTC-/-MM mice; 2 PTC2+ and 2 PTC2- cell populations were isolated using antibodies specific for PTC2 and FACS sorting.
Activated Hedgehog-GLI Signaling Causes Congenital Ureteropelvic Junction Obstruction.
Specimen part, Cell line, Subject
View SamplesGDAP1 is a mitochondrial fission factor and mutations in GDAP1 cause Charcot-Marie-Tooth disease. Gdap1 knockout mice, mimicking genetic alterations of patients suffering from severe CMT forms, develop an age-related, hypomyelinating peripheral neuropathy.
The Gdap1 knockout mouse mechanistically links redox control to Charcot-Marie-Tooth disease.
Specimen part
View SamplesGene expression analysis identified a specific signature of differentially expressed genes discriminating good and poor responders in JMML patients.
Gene expression-based classification as an independent predictor of clinical outcome in juvenile myelomonocytic leukemia.
Specimen part, Disease
View SamplesBackground and Purpose
Upregulated signaling pathways in ruptured human saccular intracranial aneurysm wall: an emerging regulative role of Toll-like receptor signaling and nuclear factor-κB, hypoxia-inducible factor-1A, and ETS transcription factors.
No sample metadata fields
View SamplesCD20 is a clinically validated target for Non-Hodgkins lymphomas and autoimmune diseases. Interactions of CD20 with the B cell receptor (BCR) and components of the BCR signaling cascade have been reported. In this study we show that antibodies against CD20 or activation of the BCR by specific antibodies induce very similar expression patterns of up- or down-regulated genes in NHL cell lines indicating that CD20 may play a role in BCR signaling and vice versa.
Antibodies against CD20 or B-cell receptor induce similar transcription patterns in human lymphoma cell lines.
Cell line, Treatment
View SamplesBackground: Several genetic defects of the nucleotide excision repair (NER) pathway, including deficiency of the Excision Repair Cross-Complementing rodent repair deficiency, complementation group 1 (ERCC1), result in pre-mature aging, impaired growth, microcephaly and delayed development of the cerebellum. Such a phenotype also occurs in ERCC1-knockout mice which survive for up to 4 weeks after birth. Therefore, we analyzed cerebellar and hippocamapal transcriptomes of these animals at 3 weeks of age to identify the candidate mechanisms underlying brain consequences of reduced ERCC1 activity.
Downregulation of cholesterol biosynthesis genes in the forebrain of ERCC1-deficient mice.
No sample metadata fields
View SamplesThe p21 RAS subfamily of small GTPases, including KRAS, HRAS, and NRAS, regulates cell proliferation, cytoskeletal organization and other signaling networks, and is the most frequent target of activating mutations in cancer. Activating germline mutations of KRAS and HRAS cause severe developmental abnormalities leading to Noonan, cardio-facial-cutaneous and Costello syndrome, but activating germline mutations of NRAS have not been reported. Autoimmune lymphoproliferative syndrome (ALPS) is the most common genetic disease of lymphocyte apoptosis and causes autoimmunity as well as excessive lymphocyte accumulation, particularly of CD4-, CD8- ab T cells. Mutations in ALPS typically affect CD95 (Fas/APO-1)-mediated apoptosis, one of the extrinsic death pathways involving tumor necrosis factor receptor (TNFR) superfamily proteins, but certain ALPS individuals have no such mutations. We show here that the salient features of ALPS as well as a predisposition to hematological malignancies can be caused by a heterozygous germline Gly13Asp activating mutation of the NRAS oncogene that does not impair CD95-mediated apoptosis. The increase in active, GTP-bound NRAS augments RAF/MEK/ERK signaling which markedly decreases the pro-apoptotic protein BIM and attenuates intrinsic, nonreceptor-mediated mitochondrial apoptosis. Thus, germline activating mutations in NRAS differ from other p21 Ras oncoproteins by causing selective immune abnormalities without general developmental defects. Our observations on the effects of NRAS activation indicate that RAS-inactivating drugs, such as farnesyl-transferase inhibitors (FTIs) should be examined in human autoimmune and lymphocyte homeostasis disorders.
NRAS mutation causes a human autoimmune lymphoproliferative syndrome.
No sample metadata fields
View Samples