Project description:Tumorigenic processes are understood to be driven by epi-/genetic and genomic alterations from single point mutations to chromosomal alterations such as insertions and deletions of nucleotides up to gains and losses of large chromosomal fragments including products of chromosomal rearrangements e.g. fusion genes and proteins. Overall comparisons of copy number alterations (CNAs) present in 48 clear cell renal cell carcinoma (ccRCC) genomes result in ratios of gene losses versus gene gains between 26 ccRCC Fuhrman malignancy grades G1 (ratio 1.25) and 20 G3 (ratio 0.58). Gene losses and gains of 15762 CNA genes are mapped to 795 chromosomal cytoband loci including 280 KEGG pathways. CNAs are classified according to their contribution to Fuhrman tumour gradings G1 and G3. Gene gains and losses turn out to be highly structured processes in ccRCC genomes enabling the subclassification and stratification of ccRCC tumours in a genome-wide manner. CNAs of ccRCC seem to start with common tumour related gene losses flanked by CNAs specifying Fuhrman grade G1 losses and CNA gains favouring grade G3 tumours. The appearance of recurrent CNA signatures implies the presence of causal mechanisms most likely implicated in the pathogenesis and disease-outcome of ccRCC tumours distinguishing lower from higher malignant tumours. Finally, the diagnostic quality of initial 201 genes (108 genes supporting G1 and 93 genes G3 phenotypes) are successfully validated on published Swiss data (GSE19949) leading to a restricted CNA gene set of 171 CNA genes of which 85 genes favour Fuhrman grade G1 and 86 genes Fuhrman grade G3. Regarding these gene sets overall survival decreases with the number of G3 related gene losses plus the total number of gene gains. CNA gene sets presented define an entry to a gene-directed and pathway-related functional understanding of ongoing copy number alterations within and between individual ccRCC tumours leading to CNA genes of prognostic and predictive value.
Project description:Intra-tumour heterogeneity (ITH) foster tumour adaptation and hamper the efficiency of personalised medicine approaches. We investigated the extent of ITH within individual clear cell renal cell carcinomas (ccRCC) by multi-region sampling and copy number analysis. We analyzed 63 tumour regions and 8 normal samples from eight clear cell renal cell carcinomas using Affymetrix SNP6 arrays. All individual tumours were subjected to multi-region sampling and copy-number analysis using Affymetrix SNP6 arrays.
Project description:Intra-tumour heterogeneity (ITH) foster tumour adaptation and hamper the efficiency of personalised medicine approaches. We investigated the extent of ITH within individual clear cell renal cell carcinomas (ccRCC) by multi-region sampling and copy number analysis. We analyzed 63 tumour regions and 8 normal samples from eight clear cell renal cell carcinomas using Affymetrix SNP6 arrays.
Project description:Human clear cell renal cell carcinoma (ccRCC) is a common cancer of the kidney. We applied an integrated approach to identify important factors that influence carcinogenesis in ccRCC. 33 frozen ccRCC samples were subject to copy number analysis. The data was analyzed to identify factors affecting tumorigenesis. The samples were also stained for HIF-1alpha and HIF-2alpha expression. The tumors were subtyped based on HIF expression and investigated for differences in genetic aberrations.
Project description:Renal cell carcinoma (RCC) exhibits some unusual features and genes commonly mutated in cancer are rarely mutated in clear-cell RCC (ccRCC), the most common type. The most prevalent genetic alteration in ccRCC is the inactivation of the tumor suppressor gene VHL. Using whole-genome and exome sequencing we discovered BAP1 as a novel tumor suppressor in ccRCC that shows little overlap with mutations in PBRM1, another recent tumor suppressor. Whereas VHL was mutated in 81% of the patients (142/176), PBRM1 was lost in 58% and BAP1 in 15% of the patients analyzed. All these tumor suppressor genes are located in chromosome 3p, which is partially or completely lost in most ccRCC patients. However, BAP1 but not PBRM1 loss was associated with higher Fuhrman grade and, therefore, poorer outcome. Xenograft tumors (tumorgrafts) implanted orthotopically in mice retained >92% of mutations and exhibited similar DNA copy number alterations to corresponding primary tumors. Thus, after inactivation of VHL, the acquisition of a mutation in BAP1 or PBRM1 defines a different program that might alter the fate of the patient. Our results establish the foundation for an integrated pathological and molecular genetic classification of about 70% of ccRCC patients, paving the way for subtype-specific treatments exploiting genetic vulnerabilities. The genomic DNA of clear-cell renal cell carcinoma (ccRCC) primary tumors, tumors growing in immunodeficient mice (tumorgrafts), and normal samples were labeled and hybridized to Affymetrix SNP arrays 6.0.
Project description:Despite numerous studies reporting deregulated microRNA (miRNA) and gene expression patterns in clear cell renal cell carcinoma (ccRCC), no direct comparisons have been made to its presumed normal counterpart; the renal proximal epithelial tubular cells (PTEC). The aim of this study was to determine the miRNA expression profiles of ten clear cell renal cell carcinoma-derived cell lines and short-term cultures of PTEC, and to correlate these with their gene expression, and copy-number profiles. Using microarray-based methods, a significantly altered expression level in ccRCC cell lines was observed for 23 miRNAs and 1630 genes. The set of miRNAs with significantly decreased expression levels include all members of the miR-200 family known to be involved in the epithelial to mesenchymal transition (EMT) process. Expression levels of 13 of the 47 validated target genes for the downregulated miRNAs were increased more than two-fold. Our data reinforce the importance of the EMT process in the development of ccRCC. For mRNA expression data of these cell lines see GEO Series accession number GSE20491. MicroRNA profiling was performed on two proximal tubular epithelial cell samples (both cell samples were hybridized twice (biological duplicates)) and ten clear cell renal cell carcinoma- derived cell lines (one of which; RCC-JF in duplicate)
Project description:The pituitary-tumor transforming gene (PTTG1) is a recently discovered oncogene implicated in the malignant progression of a number of neoplasms. It has been shown to drive both endocrine and non-endocrine malignancies, but has not yet been studied in the context of renal cell carcinoma. Here we show that PTTG1 is frequently amplified and overexpressed in clear cell renal cell carcinoma, the most common form of kidney cancer. Clear cell RCC (ccRCC) is cytogenetically characterized by deletion of chromosome 3p, harboring the von-Hippel Lindau tumor suppressor gene, and amplification of chromosome 5q. The significance of copy number gain of chromosome 5 has to date remained a mystery, but is presumably the location of oncogenes that play an important role in ccRCC development or progression. The PTTG1 oncogene maps to chromosome 5q and shows frequent copy number gain in clear cell RCC, and is significantly overexpressed in tumor tissue relative to adjacent normal kidney. Furthermore, we have established a functional role for PTTG1 in ccRCC tumorigenesis and progression. PTTG1 ablation significantly reduces both the tumorigenic ability of ccRCC cells in vitro and in vivo and the invasive ability of these cells in vitro. An analysis of PTTG1 regulatory targets supports its role in the progression of localized ccRCC to invasive and metastatic disease, an idea further substantiated by PTTG1’s clinical correlation with high grade and high stage tumors and its association with poor prognosis. PTTG1-dependent overexpression of the Rho-GEF ECT2, another proto-oncogene, is observed in a number of ccRCC cell lines, and ECT2 overexpression correlates with PTTG1 overexpression, high stage, high grade, and poor prognosis in human ccRCC tumors. As GEF’s have been promoted as viable drug targets for targeted cancer therapeutics, the relationship between the PTTG1 and ECT2 oncogenes may be able to be exploited for the treatment of this disease. SNP data on 74 ccRCC and 16 normal renal tissue samples were used to profile the cytogenetic gains or losses. The most frequent gains or losses were identified and gene expression data were then used to pinpoint the genes for further study.
Project description:Despite numerous studies reporting deregulated microRNA (miRNA) and gene expression patterns in clear cell renal cell carcinoma (ccRCC), no direct comparisons have been made to its presumed normal counterpart; the renal proximal epithelial tubular cells (PTEC). The aim of this study was to determine the miRNA expression profiles of ten clear cell renal cell carcinoma-derived cell lines and short-term cultures of PTEC, and to correlate these with their gene expression, and copy-number profiles. Using microarray-based methods, a significantly altered expression level in ccRCC cell lines was observed for 23 miRNAs and 1630 genes. The set of miRNAs with significantly decreased expression levels include all members of the miR-200 family known to be involved in the epithelial to mesenchymal transition (EMT) process. Expression levels of 13 of the 47 validated target genes for the downregulated miRNAs were increased more than two-fold. Our data reinforce the importance of the EMT process in the development of ccRCC. For mRNA expression data of these cell lines see GEO Series accession number GSE20491.
Project description:The pituitary-tumor transforming gene (PTTG1) is a recently discovered oncogene implicated in the malignant progression of a number of neoplasms. It has been shown to drive both endocrine and non-endocrine malignancies, but has not yet been studied in the context of renal cell carcinoma. Here we show that PTTG1 is frequently amplified and overexpressed in clear cell renal cell carcinoma, the most common form of kidney cancer. Clear cell RCC (ccRCC) is cytogenetically characterized by deletion of chromosome 3p, harboring the von-Hippel Lindau tumor suppressor gene, and amplification of chromosome 5q. The significance of copy number gain of chromosome 5 has to date remained a mystery, but is presumably the location of oncogenes that play an important role in ccRCC development or progression. The PTTG1 oncogene maps to chromosome 5q and shows frequent copy number gain in clear cell RCC, and is significantly overexpressed in tumor tissue relative to adjacent normal kidney. Furthermore, we have established a functional role for PTTG1 in ccRCC tumorigenesis and progression. PTTG1 ablation significantly reduces both the tumorigenic ability of ccRCC cells in vitro and in vivo and the invasive ability of these cells in vitro. An analysis of PTTG1 regulatory targets supports its role in the progression of localized ccRCC to invasive and metastatic disease, an idea further substantiated by PTTG1’s clinical correlation with high grade and high stage tumors and its association with poor prognosis. PTTG1-dependent overexpression of the Rho-GEF ECT2, another proto-oncogene, is observed in a number of ccRCC cell lines, and ECT2 overexpression correlates with PTTG1 overexpression, high stage, high grade, and poor prognosis in human ccRCC tumors. As GEF’s have been promoted as viable drug targets for targeted cancer therapeutics, the relationship between the PTTG1 and ECT2 oncogenes may be able to be exploited for the treatment of this disease.
Project description:an integrated molecular study of clear cell renal cell carcinoma (ccRCC) including whole-genome/exome and RNA sequencing as well as array-based gene expression/copy-number/methylation analyses