Transcription profiling of human myelomonocytic leukemia THP-1 cell model treated with ionizing radiation
ABSTRACT: Ionizing radiation (IR) is associated with thrombotic vascular occlusion. Thrombosis in malignancy predicts a poor clinical outcome. Tissue factor (TF) is the initiator of the extrinsic co-agulation system and induces thrombus formation. Our study examined whether IR induced TF expression and procoagulability in the myelomonocytic leukemia THP-1 cell model. We further investigated coordinated gene alterations associated with TF upregulation and IR-induced thrombogenicity. Gene expression profiling revealed IR to increase the expression of inflammatory and apoptosis-related pathways, contributing to TF upregulation and increased TF procoagulability on day 7 post IR. The upregulation of these pathways together with TF upregulation contributed to the increased thrombogenic potential of tissues post application of IR. Experiment Overall Design: THP-1 cells were harvested on day 3 (1 sample) and day 7 (3 samples) post irradiation. For each time point untreated control samples were run.
Project description:Ionizing radiation (IR) is associated with thrombotic vascular occlusion. Thrombosis in malignancy predicts a poor clinical outcome. Tissue factor (TF) is the initiator of the extrinsic co-agulation system and induces thrombus formation. Our study examined whether IR induced TF expression and procoagulability in the myelomonocytic leukemia THP-1 cell model. We further investigated coordinated gene alterations associated with TF upregulation and IR-induced thrombogenicity. Gene expression profiling revealed IR to increase the expression of inflammatory and apoptosis-related pathways, contributing to TF upregulation and increased TF procoagulability on day 7 post IR. The upregulation of these pathways together with TF upregulation contributed to the increased thrombogenic potential of tissues post application of IR. Keywords: irridiation response Overall design: THP-1 cells were harvested on day 3 (1 sample) and day 7 (3 samples) post irradiation. For each time point untreated control samples were run.
Project description:Cancer patients often have an activated clotting system and are at increased risk for venous thrombosis. In this study, we analyzed tissue factor (TF) expression in four different human pancreatic tumor cell lines for the purpose of producing derivative tumors in vivo. We found that two of the lines expressed TF and released TF-positive microparticles (MPs) into the culture medium. The majority of TF protein in the culture medium was associated with MPs. Importantly, only TF-positive cell lines activated coagulation in nude mice, and this activation was abolished by an anti-human TF antibody. Of the two TF-positive lines only one produced detectable levels of human MP TF activity in the plasma when grown orthotopically in nude mice. Surprisingly, <5% of human TF protein in plasma from tumor-bearing mice was associated with MPs. Mice with TF-positive tumors and elevated levels of circulating TF-positive MPs had increased thrombosis in a saphenous vein model. In contrast, we observed no difference in thrombus weight between tumor bearing and control mice in an inferior vena cava stenosis model. Our studies suggest that in a xenograft mouse model tumor TF activates coagulation, whereas TF on circulating MPs may trigger venous thrombosis. Overall design: 8 human tumor pancreatic cell lines
Project description:Atrial fibrillation (AF) is a major risk factor for cardioembolic stroke. Anticoagulant drugs are effective in preventing AF-related stroke. However, the high frequency of anticoagulant-associated major bleeding is a major concern particularly when antiplatelet treatment is simultaneously administered. Here, microarray analysis in peripheral blood cells in eight patients with AF and stroke and eight AF subjects without stroke identified a stroke related gene expression pattern. HSPA1B, which encodes for heat-shock protein 70 kDa (Hsp70), was the most differentially expressed gene. This gene was downregulated in stroke subjects, a finding confirmed further in an independent AF cohort of 200 individuals. Hsp70 knock-out (KO) mice subjected to different thrombotic challenges developed thrombosis significantly earlier than their wild-type (WT) counterparts. In WT mice, Hsp70 inducers (TRC051384, or tubastatin A) delayed thrombus formation. Remarkably, Hsp70 inducers did not increase the bleeding risk even when aspirin was concomitantly administered. Hsp70 induction was associated with an increased vascular thrombomodulin expression, higher circulating levels of activated protein C (APC) upon thrombotic stimulus and increased protection against endothelial apoptosis. Thus, Hsp70 induction is a novel approach to delay thrombus formation with minimal bleeding risk, being especially promising in situations where there is a major bleeding hazard. Microarray analysis in peripheral blood cells includes eight patients with AF and stroke and eight AF subjects without stroke
Project description:The antiphospholipid syndrome (APS) is an autoimmune disease in which antiphospholipid antibodies (aPL) cause vascular thrombosis (VT+) and/or pregnancy morbidity (PM+). The experiment aimed at determining whether specific aPL are associated with thrombotic or obstetric manifestations. In the present study we carried out microarray analysis comparing patterns of mRNA expression in monocytes from a healthy volunteer exposed to IgG from patients with a history of vascular thrombosis (VT+/PM-) or pregnancy morbidity (VT-/PM+) or to IgG from healthy controls (HC).
Project description:Abstract. The role of platelets in hemostasis and thrombosis is clearly established; however, the mechanisms by which platelets mediate inflammatory and immune pathways are less well understood. Platelets interact and modulate the function of blood and vascular cells by releasing bioactive molecules. Although the platelet is anucleate, it contains transcripts that may mirror disease. Platelet mRNA is only associated with low-level protein translation, however, platelets have a unique membrane structure allowing for the passage of small molecules, leading to the possibility that its’ cytoplasmic RNA may be passed to nucleated cells. To examine this question, platelet-like particles with labeled RNA were co-cultured with vascular cells. Co-culture of platelet-like particles with activated THP-1, monocytic, and endothelial cells led to visual and functional RNA transfer. Post-transfer microarray gene expression analysis of THP-1 cells showed an increase in HBG1/HBG2 and HBA1/HBA2 expression which was directly related to the transfer. Infusion of wild-type platelets into a TLR2 deficient mouse model established in vivo confirmation of select platelet RNA transfer to leukocytes. By specifically transferring green fluorescent protein, it was also observed that external RNA was functional in the recipient cells. The observation that platelets possess the capacity to transfer cytosolic RNA suggests a new function for platelets in the regulation of vascular homeostasis. THP-1, treated with Pam3CSK4, were co-cultured with platelet-like particles for 12 hours and 24 hours then collected and processed for RNA isolation. We also included as control THP-1 untreated and THP-1 treated with Pam3CSK4. A total of 4 samples were analyzed by microarray for gene expression.
Project description:Folate deficiency, arsenic exposure, and gamma-IR are known developmental toxicants and have carcinogenic effects. The mechanism by which IR is known, but the effect of arsenic or folate deficiency remains unclear. Their effect may be mediated by epigenetic alterations, leading to miRNA expression changes, and this experiment examined this hypothesis We used microarrays to detail the miRNA expression profiles of TK6 cells treated with 2 uM sodium arsenite for 6 days, folate-deficient media for 6 days, or 2.5 Gy IR exposure either acutely at 4 hours post exposure or long-term at 6 days post exposure, as well as requiste controls, all in biological triplicate. Keywords: exposure differences TK6, were cultured in standard RPMI 1640 (Invitrogen Inc., Gaithersburg, MD) or folate-deficient RPMI 1640 (Invitrogen). Growth media was supplemented with 10% fetal bovine serum (Invitrogen) and 1% penicillin-streptomycin; dialyzed fetal bovine serum (Invitrogen) was added to the folate-deficient medium in order to eliminate folic acid in the serum. For controls, folate-deficiency, arsenic exposure, and 6-day ?-IR exposure groups, 106 cells were diluted into 50ml of appropriate growth media. For the 4-hour post-?-IR exposure group, 107 cells were diluted into 50ml of growth media. For the arsenic exposed group, sodium arsenite was added to the media to a concentration of 2 ?M. For the ?-IR exposure groups, cells were diluted and allowed to incubate for 4 hours prior to irradiation treatment, and were exposed at a dose rate of 86.76 rad/min to a final dose of 2.5 Gy using a Philips MGC-40 X-ray source. Following exposure, cells were returned to the incubator. After fours hours, the short-term post-??-IR exposure group was collected for RNA isolation, as well as a mock (control) group. All experimental and control conditions were performed in triplicate. For all other groups, cells were cultured for 6 days, with the media changed and renewed, with the appropriate treatment, on day 3.
Project description:We studied genome-wide miRNA expression in THP-1 cells treated with/without AGEs. Significant upregulation of miR-214 was observed in THP-1 cells treated with/without AGEs. Two samples, one treated with AGE-BSA and one without AGEs.
Project description:We studied genome-wide miRNA expression in THP-1 cells treated with/without AGEs. Significant upregulation of miR-214 was observed in THP-1 cells treated with/without AGEs. Overall design: Two samples, one treated with AGE-BSA and one without AGEs.
Project description:Using microarray analysis, we explored the differences in gene expression profiles between individual and combined stimulation of Toll-like receptor 4 (TLR4) and Nucleotide oligomerization domain (NOD)-like receptor (NOD2) in THP-1 cells. Analysis was performed 3 hours post addition of TLR4 agonist MPLA and the NOD2 agonist MDP to THP-1 cells. The results provide the detailed molecular profile of the the genetic response to individual and combined stimulation of TLR4 and NOD2 receptors THP-1 cells (Invivogen) were seeded in 3-cm culture dishes at 1x10^6 cells per dish in RPMI medium. Next day, cells were treated with MDP (20μg/ml) and MPLA (1μg/ml) individually or in combination or left untreated.
Project description:This a model from the article:
Data assimilation constrains new connections and components in a complex, eukaryotic circadian clock model.
Pokhilko A, Hodge SK, Stratford K, Knox K, Edwards KD, Thomson AW, Mizuno T, Millar AJ.
Mol Syst Biol.2010 Sep 21;6:416.
Circadian clocks generate 24-h rhythms that are entrained by the day/night cycle. Clock circuits include several light inputs and interlocked feedback loops, with complex dynamics. Multiple biological components can contribute to each part of the circuit in higher organisms. Mechanistic models with morning, evening and central feedback loops have provided a heuristic framework for the clock in plants, but were based on transcriptional control. Here, we model observed, post-transcriptional and post-translational regulation and constrain many parameter values based on experimental data. The model's feedback circuit is revised and now includes PSEUDO-RESPONSE REGULATOR 7 (PRR7) and ZEITLUPE. The revised model matches data in varying environments and mutants, and gains robustness to parameter variation. Our results suggest that the activation of important morning-expressed genes follows their release from a night inhibitor (NI). Experiments inspired by the new model support the predicted NI function and show that the PRR5 gene contributes to the NI. The multiple PRR genes of Arabidopsis uncouple events in the late night from light-driven responses in the day, increasing the flexibility of rhythmic regulation.