Differentially expressed genes in radioresistant nasopharyngeal cancer cells
ABSTRACT: The NPC parental cell lines were seeded at a density of 1 x 105/T25 flask (30% to 40% confluency) in complete medium. After 24 hours of cell seeding, various doses from 6 to 14 Gy were administered to determine the sublethal dose for each cell line. The radiation was delivered at room temperature at 300 cGy/min with a linear accelerator (2100EX, Varian, VA, USA). To establish RR subclone, the NPC cells were received the sublethal dose of irradiation. After treatment, the surviving cells were selected and cultured to produce first generation of the subline cells. Again, the subline cells were received sublethal dose of irradiation and the surviving cells were cultured to produce next generation of the subline cells. Up to four generations of NPC cells were produced and defined the forth generation cells as RR subclone. Keywords: Parental vs. subclone cell line comparison Overall design: Array 1, NPC-076 Cy5 vers. NPC076-RR Cy3 Array 2, NPC-076-RR Cy5 vers. NPC-076 Cy3 Array 3, NPC-BM1 Cy5 vers. NPC-BM1-RR Cy3 Array 4, NPC-BM1-RR Cy5 vers. NPC-BM1 Cy3
Project description:Most of the NPC patients suffer from local recurrences and distant metastases within 1.5 years after radiotherapy due to radioresistance. Distinct patterns of gene expression and signatures were found in NPC, and have been used to associate them with cell proliferation, apoptosis, invasion and metastasis, but few gene expression profiling studies have been focused on the tumor radioresistance.We used gene expression microarray analyses to identify the difference of mRNA in radioresistant NPC CNE2-IR cells and radiosensitive CNE2 cells. Radioresistant subclone of nasopharyngeal carcinoma CNE2-IR cell line was cultured and produced according to the experienment schedule to undergo five rounds of sublethal dose of irradiation (11 Gy), and the parent cell line CNE2 cell line sensitive to radiotherapy as the control
Project description:Most of the NPC patients suffer from local recurrences and distant metastases within 1.5 years after radiotherapy due to radioresistance. Distinct patterns of miRNa expression and signatures were found in NPC, and have been used to associate them with cell proliferation, apoptosis, invasion and metastasis, but few miRNA expression profiling studies have been focused on the tumor radioresistance.We used miRNA expression microarray analyses to identify the difference of miRNA in radioresistant NPC CNE2-IR cells and radiosensitive CNE2 cells. Radioresistant subclone of nasopharyngeal carcinoma CNE2-IR cell line was cultured and produced according to the experienment schedule to undergo five rounds of sublethal dose of irradiation (11 Gy),and the parent cell line CNE2 sensitive to radiotherapy as the control
Project description:The goal of this experiment is to identify target genes of Egf signaling which regulate recovery of the neoblast population following exposure to a sublethal dose of radiation. A large population of highly proliferative stem cells (neoblasts) is required for physiological tissue homeostasis and regeneration after injury in planarians. Recent studies indicate that survival of a few neoblasts after sublethal irradiation results in the clonal expansion of the surviving stem cells and the eventual restoration of tissue homeostasis and regenerative capacity. Many genes are known to be required for the normal function of neoblasts, but the precise mechanisms regulating the population dynamics of these adult pluripotent stem cells remain largely unknown. By coupling RNAi screening and sublethal irradiation, we uncovered a central role for Epidermal Growth Factor (EGF) signaling during in vivo neoblast expansion mediated by Smed-egfr-3 (egfr-3) and its putative ligand Smed-neuregulin-7 (nrg-7). Furthermore, the EGFR-3 protein localizes asymmetrically on the cytoplasmic membrane of neoblasts and the ratio of asymmetric to symmetric cell divisions decreases significantly in egfr-3(RNAi) worms. Our results not only provide the first molecular evidence of asymmetric stem cell divisions in planarian, but also demonstrate that EGF signaling likely functions as an essential regulator of neoblast clonal expansion. Overall design: Worms were fed on a schedule every three days with RNAi against Egfr3, nrg6, nrg7, or unc22 control. One population (SR) was exposed to a sublethal dose of gamma radiation, another population continued to grow with no treatment (NT). A third population was dissected and X1 cells were isolated (X1). The experiments were performed in quadruplicate for a total of 144 samples.
Project description:Nasopharyngeal carcinoma (NPC) remains a majoy health problem worldwide, specially in Southeast China. In order to find the new candidate genes and molecular markers that are associated with nasopharyngeal carcinoma (NPC), this study focused on the screening NPC relative genes by gene expression profile. Keywords: disease state analysis 23 NPC biopsies and 15 nasopharynx chronic phlogistic biopsies were used to screen NPC relative genes by BioStarH-141s (2004) profile gene chips which contained 14112 points of full length human genes. The tumor samples were labeled with Cy5-dUTP.The nasopharyngeal phlogistic tissues were labeled with Cy3-dUTP. Biostatistics and bioinformatics were also used to analyse the differently expressed genes.
Project description:Nasopharyngeal carcinoma (NPC) remains a majoy health problem worldwide, specially in Southeast China. In order to find the new candidate genes and molecular markers that are associated with nasopharyngeal carcinoma (NPC), this study focused on the screening NPC relative genes by gene expression profile. Keywords: disease state analysis Overall design: 23 NPC biopsies and 15 nasopharynx chronic phlogistic biopsies were used to screen NPC relative genes by BioStarH-141s (2004) profile gene chips which contained 14112 points of full length human genes. The tumor samples were labeled with Cy5-dUTP.The nasopharyngeal phlogistic tissues were labeled with Cy3-dUTP. Biostatistics and bioinformatics were also used to analyse the differently expressed genes.
Project description:In order to understanding the mechanisms of action of niclosamide, the active ingredient in the molluscicides, we used a Biomphalaria glabrata oligonucleotide microarray to investigate the effect of three sublethal exposures to niclosamide on the transcriptional responses of the snail B. glabrata relative to untreated snails. In addition to inducing biotransformation activity and inducing stress responses, niclosamide exposures also resulted in altered function of vesicle trafficking and may affect the snail’s oxygen binding capacity. In order to reveal how sublethal exposures of niclosamide to the snail B. glabrata affects the snail’s gene expression. The three sublethal doses of niclosamide tested are 0.15 mg/L (dose 1), 0.10 mg/L (dose 2), and 0.05 mg/L (dose 3). The control snails did not exposed to the niclosamid (0%). The snails were exposed to a given dose for 24 hours. Twenty live snails from each dose or control group were collected and randomly divided into four replicate groups, each with five snails, for subsequent RNA extraction and transcriptome analysis
Project description:The aim of the study is to disclose the distinct alteration of biological characteristics of gene expression features in pancreas cancer cell, MIAPaCa-2, irradiated by proton and x-ray. The survived MIAPaCa-2 cells after irradiation with proton and x-ray were isolated and gene expression profiles were analyzed. Overall design: MIAPaCa-2 cells were irradiated with proton or X-ray with 8 Gy dose in vitro. After 7 to 17 days, the colonies with survival cells were picked up and expanded. RNA was isolated from each expanded surviving cells (proton-irradiated surviving cells: n =5, X-ray-irradiated surviving cells: n=4) , followed by gene expression analysis.
Project description:Arsenic is a carcinogenic metalloid element found naturally in the environment; however human activities such as mining and pesticide use have led to increased concentrations in some areas. Silurana tropicalis eggs were exposed to sublethal concentrations of sodium arsenate (0, 0.5 and 1 ppm) for 3 days during embryogenesis. Four pooled of 10 larvae were sampled per treatment and analyzed for gene expression changes using a microarray approach. Silurana tropicalis eggs were exposed to sublethal concentrations of sodium arsenate (0, 0.5 and 1 ppm) for 3 days during embryogenesis. There were 5 controls, 5 low dose and 6 high dose microarrays perfomed.
Project description:A common bacterial strategy for monitoring environmental challenges is to use two-component systems, which consist of a sensor histidine kinase (HK) and a response regulator (RR). In the food-borne pathogen Bacillus cereus, the alternative sigma factor σB is activated by the RR RsbY. Here we present strong indications that the PP2C-type phosphatase RsbY receives its input from the multi-sensor hybrid kinase BC1008 (renamed RsbK). Genome analyses revealed that, across bacilli, rsbY and rsbK are located in a conserved gene cluster. A B. cereus rsbK deletion strain was shown to be incapable of inducing σB upon stress conditions and was impaired in its heat adaptive response. Comparison of the wild-type and rsbK mutant transcriptomes upon heat shock revealed that RsbK was primarily involved in the activation of the σB-mediated stress response. Truncation of the RsbK RR receiver domain demonstrated the importance of this domain for σB induction upon stress. The domain architecture of RsbK suggests that in the B. cereus group and in other bacilli, environmental and intracellular stress signalling routes are combined into one single protein. This strategy is markedly different from the σB activation pathway in other low-GC Grampositives. Overall design: Two different comparisons were performed (both in duplo and Cy5-Cy3 dye-swapped): (1) B. cereus WT 30°C versus B. cereus WT 42°C (10 min heat shock) (2) B. cereus WT 42°C versus B. cereus FM1404 42°C Data from comparisons (2) were subsequently compared with transcriptome data obtained previously by Van Schaik et al., 2007
Project description:Microcystins (MCs) are cyclic hepatotoxins produced worldwide by various species of cyanobacteria. Their structure includes two variable amino acids (AAs) and most of the studies focused on the most toxic variant: the microcystin LR (MC-LR). However, more than 80 MC variants have been described to date. Despite ingestion being the major pathway of human exposure, few in vivo studies have demonstrated macroscopic effects on the gastro-intestinal tract, but no data are available on the affected pathways by several variants on intestinal cells. Here, using a non-selective method, we investigated for the first time the effect of MC-RR and MC-LR on the human intestinal cell line Caco-2 and compared their response at the pangenomic scale. The cells were incubated for 4 hrs or 24 hrs with the same range of sub-lethal concentrations of MC-RR or MC-LR. Low effects were observed for both variants after a short-term exposure. On the contrary, dose-dependent modulations of the genes transcription levels were noticed with MC-RR and MC-LR after 24 hrs. Furthermore, the genomic profiles induced by both variants were similar suggesting a common toxicity mechanism but with higher modulation following MC-LR than MC-RR exposure. However, the functional annotation revealed major differences between the variants effects. Indeed, the well-known MC-LR affected mainly two pathways, the oxidative stress response and the cell cycle regulation, which did not elicit significant alteration following MC-RR exposure. This work is the first comparative description of the MC-LR and MC-RR effects on a human intestinal cell model. It allowed us to suggest differences in the mechanism of toxicity for MC-RR and MC-LR. These results illustrate that the toxicity of MC variants remains a key point for risk assessment. Differentiated Caco-2 cells were exposed to microcystins in free FCS culture medium for either 4 or 24 hours. Sub-lethal concentrations of 10, 50 and 100 µM of MC-LR or MC-RR were chosen for 4 hours, while 1, 5 and 10 µM were selected for 24 hours. For each condition (including the controls), the solvent concentration was fixed to 2% EtOH for MC-LR and 1.5% of 80% MeOH for MC-RR. Four to five culture replicates per condition were done.