Project description:Meningiomas are typically considered a benign tumor that can be cured by complete surgical resection; however, a percentage of patients have recurrent disease, even after apparently complete resections. These patients require additional surgeries, radiation therapy, chemotherapy, or a combination of all three. The ability to recognize these patients prior to recurrence would promote earlier use of adjuvant therapy, thus improving overall patient outcome. Unfortunately, identification of meningiomas with this more aggressive phenotype is difficult, and standard histopathological techniques rarely suffice. The identification of genetic and molecular parameters that can help to define these more aggressive tumors would improve prognostication and treatment planning for patients with meningiomas. 1. Establish gene profiles for benign (grade 1) and aggressive (grades 2 and 3) meningiomas. 2. Determine if there are particular expression profiles that can help differentiate between benign and aggressive meningiomas. 3. Determine if there is/are specific gene(s) whose expression is/are altered in benign vs aggressive tumors. 4. Determine if there is a correlation between specific genetic abnormalities in these tumors (as analyzed by fluorescent in situ hybridization; FISH) and gene expression profiles. Our overall hypothesis is that there are molecular and biochemical changes that can be used to identify meningiomas that will have a more aggressive clinical course. Specific Aims 1 and 2: RNA from flash frozen or RNA-later preserved tissue (from all three grades of meningiomas) has been used for RNA isolation using standard protocols. RNA quantity has been determined using a RiboGreen RNA quantitation Kit (Molecular Probes), and RNA quality has been demonstrated using standard formaldehyde gels. These samples will be sent to the NINDS/NIMH microarray consortium for Affymetrix microarray analyses. Data analysis will be done using GeneSpring software (Silicon Genetics, Inc.) with assistance from consortium personnel. Specific Aim 3: Differentially expressed genes identified through microarray analyses will be analyzed using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Real time qRT-PCR is a standard technique used in our laboratory for gene expression analysis. Specific Aim 4: FISH analyses of paraffin-embedded tissue has been completed for 77 tumors. We have frozen tissue from a number of these patients. RNA from these samples will be used for microarray analyses (Specific Aims 1-3). The results of Speicifc Aims 1 and 2 will affect how we perform our correlation analyses. This will be done with the assistance of contracted statistical personnel

Project description:Histological grading of breast cancer defines morphological subtypes informative of metastatic potential, although not without considerable inter-observer disagreement and clinical heterogeneity particularly among the moderately differentiated grade II (G2) tumors. We posited that a gene expression signature capable of discerning tumors of grade I (G1) and grade III (G3) histology might provide a more objective measure of grade with prognostic benefit for patients with moderately differentiated disease. To this end, we studied the expression profiles of 347 primary invasive breast tumors analyzed on Affymetrix microarrays. Using class prediction algorithms, we identified 264 robust grade-associated markers, six of which could accurately classify G1 and G3 tumors, and separate G2 tumors into two highly discriminant classes (termed G2a and G2b genetic grades) with patient survival outcomes highly similar to those with G1 and G3 histology, respectively. Statistical analysis of conventional clinical variables further distinguished G2a and G2b subtypes from each other, but also from histologic G1 and G3 tumors. In multivariate analyses, genetic grade was consistently found to be an independent prognostic indicator of disease recurrence comparable to that of lymph node status and tumor size. When incorporated into the Nottingham Prognostic Index, genetic grade enhanced detection of patients with less harmful tumors, likely to benefit little from adjuvant therapy. Our findings show that a genetic grade signature can improve prognosis and therapeutic planning for breast cancer patients, and support the view that low and high grade disease, as defined genetically, reflect independent pathobiological entities rather than a continuum of cancer progression. Three separate breast cancer cohorts were analyzed: 1) Uppsala (n=249), 2) Stockholm (n=58), 3) Singapore (n=40). The Uppsala and Singapore data can be accessed here. The Stockholm cohort data can be accessed at GEO Series GSE1456. Experiment Overall Design: All tumor specimens were assessed on U133 A and B arrays.

Project description:Mammalian cells were grown as multicellular aggregates (spheroids) in an effort to determine the signaling events required for two cellular transformations states; primary foreskin fibroblasts (HFF-2) and glioblastoma cancer (T98G) cells, to survive at room temperature under oxygen and nutrient-deprived conditions for extended periods of time (2 weeks) and subsequently grown out from the arrested state as adherent monolayers. HFF-2 cells were cultured in DMEM supplemented with 15% fetal bovine serum and 5% carbon dioxide humidified air at 37 degrees C. T98G cells were cultured in EMEM with 10% FBS, 5% non-essential amino acids and 5% carbon dioxide humidified air at 37 degreesC. Monolayers were grown in T-185 flasks to 60% confluency then split into T-185 flasks coated with a 1% agarose mix in a 2:1 media/water ratio. Cells were suspended in 30 ml of supplemented media and grown for 4 days in order to form multicellular spheroids as described previously by our group (J. Cell. Physiol., 206 [2006] 526-536; see GSE1364 and GSE1455 for similar experiments with HEK293 cells). The suspension was removed from the flasks and centrifuged (1500 x g, 2 min) and the media removed. The pellet was returned to the flasks and then placed in vacuum bags (Dri-shield 2000 moisture barrier bag from Surmount Inc., USA; Cat. number 70068), which were sealed immediately under vacuum (Deni Magic Vac, Champion model; Keystone Manufacturing, USA). Vacuum-sealed flasks were stored for 2 weeks (in the dark) at room temperature. Recovery was initiated by removing the flask from the bag and resuspending the spheroids in supplemented media and placing the flasks in a 5% CO2/humidified air incubator maintained at 37 degreesC. Timepoints for transcriptional analysis were monolayer (control), 4 day growth spheroids, 2 week stored spheroids and 7 day growth back to monolayers. There were 67 HFF-2 and 50 T98G genes that exhibited at least a 10-fold change in expression during the course of arrest and recovery. Eleven of these genes were common to both cell lines. While the trends were the same between the two cell lines for genes that were in common, the timing of the responses were clearly different. The primary fibroblasts showed significant gene expression changes during spheroid formation and returned to their initial monolayer state after the two week arrest, whereas the glioblastoma cells exhibited major changes in gene expression during the recovery process. Furthermore, the T98G cells never returned to the monolayer expression levels during the time course of the recovery phase (7 days growth under monolayer conditions). Major differences in the transcriptional data were also found between the cell lines with regards to the putative cellular location of the encoded proteins. Of the genes with significant fold changes (+/- 10-fold) for which location information is available, the primary fibroblasts were significantly enriched in genes encoding extracellular (32%) and membrane-associated (26%) proteins. The glioblastoma cells, on the other hand, had only 17% extracellular and 13% membrane-associated. The expression level trends for all genes above the 10-fold cutoff were as observed for the "in common" genes; HFF-2 genes had returned to monolayer expression levels after 7 days of recovery whereas the T98G line was still exhibiting expression values much different from that of the monolayer control.

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Transcription profiling of human glioma tumor samples

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