Parent vs. Induced drug tolerant cells Microarray Analysis
Ontology highlight
ABSTRACT: WM164 BRAF mutant Melanoma cells were treated with 500nM PLX4032 for 16 days and their gene expression was compared to parent cells kept in DMSO. WM164 treated and untreated cells were kept in triplicate and the mRNA from individual samples were isolated independently for analysis.
Project description:The aim of our study is to increase understanding of the antiproliferative and pro-apoptotic potency of resveratrol by identifying genes which underlie involved pathological pathways and biological process. Therefore, we performed a gene Chip Transcription Analysis with subsequent Protein ANalysis THrough Evolutionary Relationships (PANTHER) analysis to evaluate which transcripted genes are significantly influenced by resveratrol. To determine the transcriptional profile of resveratrol, three biological replicates were processed on Affymetrix Gene Chip Human 1.0 ST.
Project description:Hypoxia triggers aggressive cancer growth and contributes to chemotherapy resistance. Novel therapeutic strategies aim at targeting hypoxia activated signaling pathways. Tumor hypoxia not only affects neoplastic tumor cells but also the surrounding stroma cells. Therefore, a novel ex vivo model was established, which allows the study of hypoxia effects in fragments of non-small cell lung cancer (NSCLC) with preserved tumor microenvironment and 3D-structure. Microarray analysis identified 107 significantly regulated genes with at least two-fold expression change in hypoxic compared to normoxic fragments. However, only four genes were significantly regulated in both subtypes, adenocarcinoma and squamous cell carcinoma. The hypoxic regulation of these four genes was verified in an independent set using quantitative PCR. Non-small cell lung cancer (NSCLC) fragments were cultured ex vivo under hypoxia or normoxia for three days. cDNA microarray analysis was performed in hypoxic and normoxic lung cancer fragments from ten patients.
Project description:As susceptibility to many adult disorders originates in utero, we here hypothesized that fetal sex influences gene expression in placental cells and produces functional differences in human placentas. We found that fetal sex differentially affects gene expression in a cell-phenotype dependent manner among all four placental cell-phenotypes studied: cytotrophoblasts, syncytiotrophoblasts, arterial endothelial cells and venous endothelial cells. The markedly enriched pathways in males were identified to be signaling pathways for graft-versus-host disease as well as the immune and inflammatory systems, both supporting the hypothesis that there is reduced maternal-fetal compatibility for male fetuses. Our study is the first microarray study investigating sexual dimorphism in purified and characterized somatic cells from a single human tissue, the placenta, that underlines the importance of considering fetal sex as an independent variable in any work using human placenta. Arterial and venous endothelial cells were isolated from eight different placentas, four of each sex. A total of ten placentas were used for isolation of cytotrophoblasts and six for syncytiotrophoblasts, with equal numbers from each sex.
Project description:The classical sacrococcygeal chordoma tumor presents with a typical morphology of lobulated myxoid tumor tissue with cords, strands and nests of tumor cells consisting of small non-vacuolated cells, intermediate cells with a wide range of vacuolization and large heavily vacuolated (physaliferous) cells. Because of its rare incidence, lack of suited model systems and technical limitations analysis was only performed on bulk tumor mass neglecting its heterogeneous composition. We aimed at elucidating the differences between small non-vacuolated and large physaliferous cells on the genomic and transcriptomic level. Secondly, we intended to clarify whether the observed cell types are derived from genetically distinct clones or rather represent different phenotypes. Using the chordoma cell line MUG-Chor1 we monitored morphological changes via time lapse experiments. We isolated pure fractions of each phenotype by means of laser microdissection or micromanipulation allowing phenotype-specific analysis. Pools of 100 cells each were genetically profiled after whole genome amplification by array comparative genomic hybridization. For expression analysis 20 cells each were subjected to whole transcriptom amplification, forwarded to RNA microarray analysis and qRT-PCR. Time lapse analysis unveiled small non-vacuolated cells to develop into large physaliferous cells via intermediate cells containing an increasing amount of vacuoles. Furthermore, we showed small and large physaliferous cells to proliferate at the same rate but intermediate cells to be the most proliferating cell phenotype. Small non-vacuolated and large physaliferous cells showed identical copy number variations. Despite their obvious morphological disparities we detected only modest changes in over all gene expression. However, verification of candidate genes yielded significant up-regulation of ALG11 (700-fold), PPP2CB (18.6-fold), and UCHL3 (18.7-fold) in large physaliferous cells. Of two different cell types (large and small MUG-Chor1 cells) we analysed each in triplicates. In total 6 cell pools were analysed.
Project description:Differential gene expression analysis of parental and resistant sub-lines of melanoma cell lines treated or untreated with PLX4032 Using microarray we sought to obtain a genome-wide profile of differentially expressed genes in parental melanoma cell lines and resistant sub-lines in response to PLX4032 vs DMSO control treatment. Representative parental melanoma cell lines and resistant sub-lines were treated with PLX4032 at 1 uM or DMSO control for 6h. Total RNA was extracted and cDNAs were generated and hybridized onto GeneChip Human Gene 1.0 ST Arrays (Affymetrix).
Project description:Microarray expression analysis to identify global changes in transcription in response to RAF inhibition. Genes under RAF control were identified in a panel of BRAFV600E tumor cells, following the short-term inhibition of RAF using a pan-RAF kinase inhibitor, PLX4032 (Plexxikon). For comparison with changes in gene expression in response to MEK inhibition using PD0325901 (Pfizer), the following array data was referenced: (http://www.ncbi.nlm.nih.gov/geo/ (accession no. GSE10086)). Cell lines growing in culture (n=5) were treated with the RAF inhibitor PLX4032 (250nM or 1000nM) or vehicle alone (0.1% DMSO) as control, for eight hours.
Project description:Multiple myeloma (MM) is a malignant disorder characterized by the clonal proliferation of plasma cells (PCs) in the bone marrow (BM). The genetic background and clinical course of the disease are largely heterogeneous, and MM pathophysiology ranges from the premalignant condition of monoclonal gammopathy of undetermined significance (MGUS) to smoldering MM, symptomatic MM, and extramedullary MM/plasma cell leukemia (PCL). Recent genome-wide sequencing efforts have provided the rationale for molecularly aimed treatment approaches, identifying mutations that can be specifically targeted, such as those in the mitogen-activated protein kinase (MAPK) pathway, which represent the most prevalent mutations in MM. Among these, mutations affecting BRAF gene, detected in 4-15% of patients, are of potential immediate clinical relevance due to the availability of effective inhibitors of this serine-threonine kinase which are in fact being explored also in myeloma. In this study, we screened by next generation sequencing (NGS) a large and representative series of intramedullary and extramedullary MM patients, including primary and secondary plasma cell leukemia (pPCL and sPCL, respectively), for mutations in BRAF, NRAS and KRAS genes. We evaluated the relationship of identified variants with other clinical and biological features and determined the transcriptional signature associated with MAPK pathway activation in MM. To further elucidate the transcriptional programs modulated by BRAF activation in MM, we used the PLX4032 drug to inhibit BRAF activity in U266 human myeloma cell line (HMCL), carrying K601N mutation and showing constitutive activation of MEK/ERK signaling. After confirming its ability to suppress MAPK pathway and myeloma cell proliferation in culture in the U266 cell line, we investigated the specific modulation of gene expression induced by the drug. U266 cells were treated with PLX4032 (30 µM) or DMSO for 12 hours and subjected to gene expression profiling (GEP) analysis by using Affymetrix GeneChip Human Gene 1.0ST arrays.
Project description:Human testicular cells were isolated mechanically and enzymatically from testis of braindead donors and from urological samples. The expression of genes was studied at baseline and 1,25(OH)2D treated conditions. We used microarrays to analyze the gene expression underlying vitamin D metabolism in human testis cells and identified distinct classes of up-regulated genes during this process. Testicular primary cells were treated with 100nM 1,25(OH)2D for 24h and gene expression studied by microarray on transcript level.
Project description:WM164 BRAF mutant Melanoma cells were treated with 500nM PLX4032 for 16 days and their gene expression was compared to parent cells kept in DMSO.
Project description:Thousands of enhancers are characterized in the human genome, yet few have been shown important in cancer. Inhibiting oncokinases, such as EGFR, ALK, HER2, and BRAF, is a mainstay of current cancer therapy but is hindered by innate drug resistance mediated by upregulation of the HGF receptor, MET. The mechanisms mediating such genomic responses to targeted therapy are unknown. Here, we identify lineage-specific MET enhancers for multiple common tumor types, including a melanoma lineage-specific MET enhancer that displays inducible chromatin looping and MET gene induction upon BRAF inhibition. Epigenomic analysis demonstrated that the melanocyte-specific transcription factor, MITF, mediates this enhancer function. Targeted genomic deletion (<7bp) of the MITF motif within the MET enhancer suppressed inducible chromatin looping and innate drug resistance, while maintaining MITF-dependent, inhibitor-induced melanoma cell differentiation. Epigenomic analysis can thus guide functional disruption of regulatory DNA to decouple pro- and anti-oncogenic functions of tumor lineage-enriched transcription factors mediating innate resistance to oncokinase therapy. COLO829 human melanoma cell line harboring the BRAFV600E mutation was treated with BRAF inhibtior PLX4032 (Vemurafenib) and/or a hairpin against MITF