Project description:[original title] Genomic expression and single-nucleotide polymorphism profiling discriminates chromophobe renal cell carcinoma and oncocytoma. Background : Chromophobe renal cell carcinoma (chRCC) and renal oncocytoma are two distinct but closely related entities with strong morphologic and genetic similarities. While chRCC is a malignant tumor, oncocytoma is usually regarded as a benign entity. The overlapping characteristics are best explained by a common cellular origin, and the biologic differences between chRCC and oncocytoma are therefore of considerable interest in terms of carcinogenesis, diagnosis and clinical management. Previous studies have been relatively limited in terms of examining the differences between oncocytoma and chromophobe RCC. Methods : Gene expression profiling using the Affymetrix HGU133Plus2 platform was applied on chRCC (n=15) and oncocytoma specimens (n=15). Supervised analysis was applied to identify a discriminatory gene signature, as well as differentially expressed genes. Immunohistochemical validation was performed in an independent set of tumors. Results : A novel 14 probe-set signature was developed to classify the tumors internally with 93% accuracy, and this was successfully validated on an external data-set with 94% accuracy. Parafibromin, aquaporin 6, and synaptogyrin 3 were novel immunohistochemical markers effectively discriminating the two pathologic entities. Conclusion : Gene expression profiles and pathway analysis effectively distinguish chRCC from oncocytoma. We have generated a novel transcript predictor that is able to discriminate between the two entities accurately, and which has been validated both in an internal and an independent data-set, implying generalizability. We have identified a series of immunohistochemical markers that are clinically useful in discriminating chRCC and oncocytoma. 30 mRNA profiling samples (15 chromophobe RCC, 15 oncocytoma)
Project description:[original title] Genomic expression and single-nucleotide polymorphism profiling discriminates chromophobe renal cell carcinoma and oncocytoma. Background : Chromophobe renal cell carcinoma (chRCC) and renal oncocytoma are two distinct but closely related entities with strong morphologic and genetic similarities. While chRCC is a malignant tumor, oncocytoma is usually regarded as a benign entity. The overlapping characteristics are best explained by a common cellular origin, and the biologic differences between chRCC and oncocytoma are therefore of considerable interest in terms of carcinogenesis, diagnosis and clinical management. Previous studies have been relatively limited in terms of examining the differences between oncocytoma and chromophobe RCC. Methods : Gene expression profiling using the Affymetrix HGU133Plus2 platform was applied on chRCC (n=15) and oncocytoma specimens (n=15). Supervised analysis was applied to identify a discriminatory gene signature, as well as differentially expressed genes. Immunohistochemical validation was performed in an independent set of tumors. Results : A novel 14 probe-set signature was developed to classify the tumors internally with 93% accuracy, and this was successfully validated on an external data-set with 94% accuracy. Parafibromin, aquaporin 6, and synaptogyrin 3 were novel immunohistochemical markers effectively discriminating the two pathologic entities. Conclusion : Gene expression profiles and pathway analysis effectively distinguish chRCC from oncocytoma. We have generated a novel transcript predictor that is able to discriminate between the two entities accurately, and which has been validated both in an internal and an independent data-set, implying generalizability. We have identified a series of immunohistochemical markers that are clinically useful in discriminating chRCC and oncocytoma.
Project description:Renal cell carcinoma is the most common neoplasm of the adult kidney. A few subtypes of RCC include papillary RCC (pRCC), chromophobe RCC (chRCC) and the benign oncocytoma tumor. In some cases, distinguishing between the RCC subyptes is difficult. We performed a mircroRNA (miRNA) microarray to determine differential miRNA expression between pRCC, chRCC, and oncocytoma. We performed a miRNA microarray on 10 tumor samples of each papillary renal cell carcinoma (pRCC), chromophobe renal cell carcinoma (chRCC), and oncocytoma.
Project description:This study aims to compare gene expression profiles of chromophobe renal cell carcinoma (RCC) and benign oncocytoma, aiming at identifying differentially expressed genes.
Project description:This study aims to compare gene expression profiles of chromophobe renal cell carcinoma (RCC) and benign oncocytoma, aiming at identifying differentially expressed genes. Experiment Overall Design: Nine cases each of chromophobe RCC and oncocytoma were analyzed by oligonucleotide microarray. Candidate genes that showed consistent differential expression were validated by RT-PCR using 25 fresh-frozen and 15 formalin-fixed paraffin-embedded tumor samples. Immunohistochemical analysis was also performed for two selected gene products, Claudin 8 and MAL2.
Project description:Renal cell carcinoma is the most common neoplasm of the adult kidney. A few subtypes of RCC include papillary RCC (pRCC), chromophobe RCC (chRCC) and the benign oncocytoma tumor. In some cases, distinguishing between the RCC subyptes is difficult. We performed a mircroRNA (miRNA) microarray to determine differential miRNA expression between pRCC, chRCC, and oncocytoma.
Project description:Copy number variant (CNV) analysis was performed on renal cell carcinoma (RCC) specimens (chromophobe, clear cell, oncocytoma, papillary type 1, papillary type 2) using high resolution arrays (1.85 million probes). RCC samples exhibited diverse genomic changes within and across tumor types ranging from 106 CNV segments in a clear cell specimen to 2238 CNV segments in a papillary type 2 specimen. Despite the genomic heterogeneity, distinct CNV segments were common within each of 4 tumor classifications: chromophobe (7 segments), clear cell (3 segments), oncocytoma (9 segments), and papillary type 2 (2 segments). Shared segments ranged from a 6.1 Kb deletion among oncocytomas to a 208.3 Kb deletion common to chromophobes. Among common tumor type-specific variations, chromophobe, clear cell and oncocytomas comprised exclusively non-coding DNA. No CNV regions were common to papillary type 1 specimens although there were 12 amplifications and 12 deletions in 5 of 6 samples. Three microRNAs and 12 mRNA genes had ≥ 98% of their coding region contained within CNV regions including multiple gene families (chromophobe: amylase 1A, 1B, 1C; oncocytoma: general transcription factor 2H2, 2B, 2C, 2D). Gene deletions involved in histone modification and chromatin remodeling affected individual subtypes (clear cell: SFMBT, SETD2; papillary type 2: BAZ1A) as well as the collective RCC group (KDM4C). The genomic amplifications/deletions identified in each renal tumor type represent potential diagnostic and/or prognostic biomarkers.