Project description:LC-MS/MS was used to profile total phosphotyrosine phosphatase in acute myeloid leukemia (AML) in order to find potential biomarkers, drug targets, signatures for AML classification, and its relationship with total phosphotyrosine amount in the samples.
Project description:Gene regulation by DNA binding small molecules could have important therapeutic applications. This study reports the investigation of a DNA-binding pyrrole-imidazole polyamide targeted to bind the DNA sequence 5M-bM-^@M-^Y-WGGWWW-3M-bM-^@M-^Y with reference to its potency in a subcutaneous xenograft tumor model. The molecule is capable of trafficking to the tumor site following subcutaneous injection and modulates transcription of select genes in vivo. A FITC-labeled analogue of this polyamide can be detected in tumor-derived cells by confocal microscopy. RNA deep sequencing (RNA-seq) of tumor tissue allowed the identification of further affected genes, a representative panel of which were interrogated by qRT-PCR and correlated with cell culture expression levels. Xenografts. Grafting with A549-luc-C8. Experiments were performed in female SCID-beige mice (Charles River) between 8 and 12 weeks of age. Cells were injected into the left flank area of the animals as suspensions of 25 x 106 mL-1 in RPMI, 200 M-BM-5L per injection. Treatment and tumor proliferation monitoring. Mice were treated following the schedule delineated in treatment protocol. Tumor proliferation was monitored using the XENOGEN imaging device. The animals were anesthetized with 2 5 % isoflurane and subsequently transferred to the imaging chamber, whereupon the isoflurane levels were reduced to 1-2.5 %. The floor of the imager was heated to +37 M-BM-:C to avoid hypothermia. Breathing frequency was monitored and not allowed to drop below 1 s-1, adjusting the isoflurane levels accordingly at all times. Endpoint criteria and euthanasia. Animal endpoint criteria encompassed weight loss of over 15 %, restriction of motor function by the engrafted tumor, dehydration of over 10 % and moribund behavior. Where appropriate, the animals were euthanized by asphyxiation in a CO2 chamber. Tumor tissue harvest. Animals were resected and tumors excised using standard forceps, scissors and surgical blades. The tumors were combined into one sample per condition and mechanically sheared in TRIZOL, employing a specialized device (tissue tearer, model 985370). Total RNA workup was performed following the standard TRIZOL procedure, followed by a DNAse digest.
Project description:The total protein expression level of 11 paired human normal, human lung cancer samples and correspoding mouse xenograft samples were analyzed by LC-MS/MS. These protein expression data were than compared with corresponding DNA copy number changes and mRNA expression level changes among these samples.
Project description:Colon cancers typically contain tumor cell populations with differential WNT signaling activity. Colon cancer cells with high WNT-activity have been attributed increase tumorigenic potential and stem cell characteristics. We extracted tumor cells with differential WNT activity using fluorescent reporters from xenografted human colon cancer cell line tumors and primary human colon cancer xenografts and analysed their gene expression profiles. Colon cancer cell lines and primary colon cancer xenografts were transduced with lentiviral TOP-GFP reporters, and grown as xenografts in NOD-SCID mice. We disaggregated these tumors, flow sorted for GFPhigh and GFPlow tumor cells and subjected these populations to gene expression profiling.
Project description:In this study, the human Burkitt’s Lymphoma cell line BL60 has been analysed via proteomic and phosphoproteomic analysis for effect of a knock down of the serine hydroxymethyltransferase 2 (shSHMT2) compared to a control construct (shGL2). Concerning the phosphoproteome, these results have been compared to an analysis of a knock down of CD79a (shCD79a) in these cells.
Project description:131 patient-derived xenograft models were generated for non-small cell lung carcinoma and were profiled at the genome, transcriptome and proteome level by analysis of gene copy number variation, whole exome sequencing, DNA methylation, transcriptome, proteome and phospho(Tyr)-proteome. At the proteome level, the human tumor and murine stroma were discernible. Tumor proteome profiling resolved the known major histological subtypes and revealed 3 proteome subtypes (proteotypes) among adenocarcinoma and 2 in squamous cell carcinoma that were associated with distinct protein-phosphotyrosine signatures and patient survival. Stromal proteomes were similar between histological subtypes, but two adenocarcinoma proteotypes had distinct stromal proteomes. Proteotypes comprise tumor and stromal signatures of targetable biological pathways suggesting that patient stratification by proteome profiling may be an actionable approach to precisely diagnose and treat cancer.
Project description:Acquired BRAF/MEK inhibitor resistance in melanoma results in a new transcriptional state associated with increased risk of metastasis. Here, we identified non-canonical EphA2 signaling as a driver of the resistance-associated metastatic state. We used mass spectrometry-based proteomic and phenotypic assays to demonstrate that the expression of active non-canonical EphA2-S897E in melanoma cells led to a mesenchymal-to-amoeboid transition (MAT) driven by Cdc42 activation. The induction of MAT promoted melanoma cell invasion, survival under shear stress, adhesion to endothelial cells under continuous flow conditions, increased permeability of endothelial cell monolayers and stimulated melanoma transendothelial cell migration. In vivo, melanoma cells expressing EphA2-S897E or active Cdc42 showed superior lung retention following tail-vain injection. Analysis of BRAF inhibitor-sensitive and -resistant melanoma cells demonstrated resistance to be associated with an MAT switch, upregulation of Cdc42 activity, increased invasion, and transendothelial migration. The drug resistant metastatic state was dependent upon histone deacetylase 8 (HDAC8) activity. Silencing of HDAC8 lead to inhibition of EphA2 and AKT phosphorylation, reduced invasion and impaired melanoma cell-endothelial cell interactions. In summary, we have demonstrated that the metastatic state associated with acquired BRAF inhibitor resistance is dependent on non-canonical EphA2 signaling, leading to increased melanoma-endothelial cell interactions and enhanced tumor dissemination.
Project description:Ewing Sarcoma is caused by a pathognomonic genomic translocation that places an N-terminal EWSR1 gene in approximation with one of several ETS genes (typically FLI1). This aberration, in turn, alters the transcriptional regulation of more than five hundred genes and perturbs a number of critical pathways that promote oncogenesis, cell growth, invasion, and metastasis. Among them, translocation-mediated up-regulation of the insulin-like growth factor receptor 1 (IGF-1R) and mammalian target of rapamycin (mTOR) are of particular importance since they work in concert to facilitate IGF-1R expression and ligand-induced activation, respectively, of proven importance in ES transformation. When used as a single agent in Ewing sarcoma therapy, IGF-1R or mTOR inhibition leads to rapid counter-regulatory effects that blunt the intended therapeutic purpose. Therefore, identify new mechanisms of resistance that are used by Ewing sarcoma to evade cell death to single-agent IGF-1R or mTOR inhibition might suggest a number of therapeutic combinations that could improve their clinical activity. Male non-obese diabetic (NOD)-SCID-IL-2Rgnull mice were used to generate EW5 explants (2 mm). Mice bearing subcutaneous tumors were randomized into treatment and control groups when their tumors reached a diameter of 6 mm and received MK-8669 (mTOR inhibitor, 5mg/kg per dose, once weekly), MK-0646 (IGF-1R inhibitor monoclonal antibody, 0.5mg IP twice weekly), or a placebo control (sterile buffer). Animals were treated either until their tumors reached 1500 mm3 in volume. Affymetrix Geneship profiling of EW5 xenografts treated in vivo either with MK-0646, MK-8669, and control and compared each other using extracted RNA and hybridized on Affymetrix microrrays ( Affymetrix Human Genome U133A 2.0 cartridge arrays).
Project description:In order to confirm the role of fatty acid β-oxidation in Src regulation, we performed gene expression analysis in MDA231 cells from in vivo model treated with ETX or knockdown of CPT1 or CPT2 using shRNA. As expected, inhibition of β-oxidation showed a gene expression pattern that is opposite to the published Src regulated gene pattern. The known Src up-regulated genes are down-regulated and Src down-regulated genes are up-regulated in β-oxidation inhibited cells. Western Blotting further confirmed the gene expression pattern. Knockdown of CPT1 or CPT2 inhibited Src Y416 autophosphorylation as observed with ETX. MDA231 cells were treated with ETX or knockdown of CPT1 or CPT2 using shRNA. Gene expression profiles were taken for each group and compared with control group (shRNA scramble). Multiple group comparison [MDA231-Scramble (C), MDA231-Scramble +ETX (D), MDA231-shCPT-1 (E) and MDA231-shCPT-2 (F)]
Project description:Microarray gene expression analysis of genes that showed a gene copy number difference in non small cell lung cancer samples. Only data for a subset of the genes on the array chip are shown here.