Project description:In this study gene expression profiles for 307 cases of advanced bladder cancers were compared to molecular phenotype at the tumor cell level. TUR-B tissue for RNA extraction was macrodissected from the close vicinity of the tissue sampled for immunohistochemistry to ensure high-quality sampling and to minimize the effects of intra-tumor heterogeneity. Despite excellent agreement between gene expression values and IHC-score at the single marker level, broad differences emerge when samples are clustered at the global mRNA versus tumor cell (IHC) levels. Classification at the different levels give different results in a systematic fashion, which implicates that analysis at both levels is required for optimal subtype-classification of bladder cancer.
Project description:The optimal treatment of patients with cancer depends on establishing accurate diagnoses by using a complex combination of clinical and histopathological data. In some instances, this task is difficult or impossible because of atypical clinical presentation or histopathology. To determine whether the diagnosis of multiple common adult malignancies could be achieved purely by molecular classification, we subjected 218 tumor samples, spanning 14 common tumor types, and 90 normal tissue samples to oligonucleotide microarray gene expression analysis. The expression levels of 16,063 genes and expressed sequence tags were used to evaluate the accuracy of a multiclass classifier based on a support vector machine algorithm. Overall classification accuracy was 78%, far exceeding the accuracy of random classification (9%). Poorly differentiated cancers resulted in low-confidence predictions and could not be accurately classified according to their tissue of origin, indicating that they are molecularly distinct entities with dramatically different gene expression patterns compared with their well differentiated counterparts. Taken together, these results demonstrate the feasibility of accurate, multiclass molecular cancer classification and suggest a strategy for future clinical implementation of molecular cancer diagnostics. golub-00236 Assay Type: Gene Expression Provider: Affymetrix Array Designs: Hu35KsubA, Hu6800 Organism: Homo sapiens (ncbitax) Material Types: synthetic_RNA, organism_part, whole_organism, total_RNA Disease States: Colorectal Adenocarcinoma, Melanoma, Normal, pancreatic adenocarcinoma, Acute Myeloid Leukemia, Breast Adenocarcinoma, T-cell ALL, Lung Adenocarcinoma, bladder transitional cell carcinoma, Ovarian Adenocarcinoma, Mesothelioma, B-cell ALL, prostate adenocarcinoma, Medulloblastoma, Follicular Lymphoma, renal cell carcinoma, uterine adenocarcinoma, large B-cell lymphoma, Glioblastoma, bladder transitonal cell carcinoma
Project description:Most epithelial ovarian cancers are thought to arise from different cells in the ovarian or fallopian tube epithelium. We hypothesized that these distinct cells-of-origin may play a role in determining ovarian tumor phenotype and also could inform the molecular classification of ovarian cancer. To test this hypothesis, we developed new methods to isolate and culture paired normal human ovarian (OV) and fallopian tube (FT) epithelial cells from multiple donors without cancer and identified a cell-of-origin gene expression signature that distinguished these cell types within the same patient. Application of the OV versus FT cell-of-origin gene signature to gene expression profiles of primary ovarian cancers permitted identification of distinct OV and FT-like subgroups among these cancers. Importantly, the normal FT-like tumor classification correlated with a significantly worse disease-free survival. This work describes a new experimental method for culture of normal human OV and FT epithelial cells from the same patient. These findings provide new evidence that cell-of-origin is an important source of ovarian tumor heterogeneity and the associated differences in tumor phenotype. We analyzed 12 samples from two donor patients and established cultures of both ovarian epithelium and fallopian tube epithelium (hTERT immortalized), each with 3 replicates (different culture passages).
Project description:Most epithelial ovarian cancers are thought to arise from different cells in the ovarian or fallopian tube epithelium. We hypothesized that these distinct cells-of-origin may play a role in determining ovarian tumor phenotype and also could inform the molecular classification of ovarian cancer. To test this hypothesis, we developed new methods to isolate and culture paired normal human ovarian (OV) and fallopian tube (FT) epithelial cells from multiple donors without cancer and identified a cell-of-origin gene expression signature that distinguished these cell types within the same patient. Application of the OV versus FT cell-of-origin gene signature to gene expression profiles of primary ovarian cancers permitted identification of distinct OV and FT-like subgroups among these cancers. Importantly, the normal FT-like tumor classification correlated with a significantly worse disease-free survival. This work describes a new experimental method for culture of normal human OV and FT epithelial cells from the same patient. These findings provide new evidence that cell-of-origin is an important source of ovarian tumor heterogeneity and the associated differences in tumor phenotype.
Project description:This is a comprehensive genomic characterization of 40 urothelial bladder carcinoma (UBC) cell lines including information on origin, mutation status of genes implicated in bladder cancer (FGFR3, PIK3CA, TP53, and RAS), copy number alterations assessed using high density SNP arrays, uniparental disomy (UPD) events, and gene expression. Based on gene mutation patterns and genomic changes we identify lines representative of the FGFR3-driven tumor pathway and of the TP53/RB tumor suppressor-driven pathway. High-density array copy number analysis identified significant focal gains (1q32, 5p13.1-12, 7q11, and 7q33) and losses (i.e. 6p22.1) in regions altered in tumors but not previously described as affected in bladder cell lines. We also identify new evidence for frequent regions of UPD, often coinciding with regions reported to be lost in tumors. Previously undescribed chromosome X losses found in UBC lines also point to potential tumor suppressor genes. Cell lines representative of the FGFR3-driven pathway showed a lower number of UPD events. Overall, there is a predominance of more aggressive tumor subtypes among the cell lines. We provide a cell line classification that establishes their relatedness to the major molecularly-defined bladder tumor subtypes. The compiled information should serve as a useful reference to the bladder cancer research community and should help to select cell lines appropriate for the functional analysis of bladder cancer genes, for example those being identified through massive parallel sequencing. Copy Number Variations were assessed in 45 bladder cell lines, included in the UBC-40 Urothelial Bladder Cell Line Index, with Human1M-Duov3 DNA Analysis BeadChip platform
Project description:This is a comprehensive genomic characterization of 40 urothelial bladder carcinoma (UBC) cell lines including information on origin, mutation status of genes implicated in bladder cancer (FGFR3, PIK3CA, TP53, and RAS), copy number alterations assessed using high density SNP arrays, uniparental disomy (UPD) events, and gene expression. Based on gene mutation patterns and genomic changes we identify lines representative of the FGFR3-driven tumor pathway and of the TP53/RB tumor suppressor-driven pathway. High-density array copy number analysis identified significant focal gains (1q32, 5p13.1-12, 7q11, and 7q33) and losses (i.e. 6p22.1) in regions altered in tumors but not previously described as affected in bladder cell lines. We also identify new evidence for frequent regions of UPD, often coinciding with regions reported to be lost in tumors. Previously undescribed chromosome X losses found in UBC lines also point to potential tumor suppressor genes. Cell lines representative of the FGFR3-driven pathway showed a lower number of UPD events. Overall, there is a predominance of more aggressive tumor subtypes among the cell lines. We provide a cell line classification that establishes their relatedness to the major molecularly-defined bladder tumor subtypes. The compiled information should serve as a useful reference to the bladder cancer research community and should help to select cell lines appropriate for the functional analysis of bladder cancer genes, for example those being identified through massive parallel sequencing. Expression levels were assessed in 20 bladder cell lines, included in the UBC-40 Urothelial Bladder Cell Line Index, with Affymetrix U133 array platform
Project description:Background. Colorectal cancer develops through two main genetic instability pathways characterized by distinct pathologic features and clinical outcome. Results. We investigated colon cancer samples (23 characterized by microsatellite stability, MSS, and 16 by high microsatellite instability, MSI-H) for genome-wide expression of microRNA (miRNA) and mRNA. Based on combined miRNA and mRNA gene expression, a molecular signature consisting of twenty seven differentially expressed genes, inclusive of 8 miRNAs, could correctly distinguish MSI-H versus MSS colon cancer samples. Among the differentially expressed miRNAs, various members of the oncogenic miR-17-92 family were significantly up-regulated in MSS cancers. The majority of protein coding genes were also up-regulated in MSS cancers. Their functional classification revealed that they were most frequently associated with cell cycle, DNA replication, recombination, repair, gastrointestinal disease and immune response. Conclusions. This is the first report that indicates the existence of differences in miRNA expression between MSS versus MSI-H colorectal cancers. In addition, the work suggests that the combination of mRNA/miRNA expression signatures may represent a general approach for improving bio-molecular classification of human cancer.