RNA-sequencing analysis of 5' capped RNAs identifies novel differentially expressed genes in sessile serrated colon polyps (SSPs)
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE46513 | GEO | 2014/04/29
SECONDARY ACCESSION(S): PRJNA200709
REPOSITORIES: GEO
Similar Datasets
Project description:RNA-sequencing of SSP RNA from patients with serrated polyposis syndrome identifies VSIG1 and MUC17 as potential diagnostic markers for SSPs 5' capped RNA from seven ascending SSPs, six patient matched uninvolved right colon and two normal right colon samples was used for RNA sequencing (15 samples total)
2014-04-29 | E-GEOD-46513 | biostudies-arrayexpress
Project description:RNA sequencing analysis of gene expression in serrated colon polyps, uninvolved colon and control colon
2016-04-08 | GSE76987 | GEO
Project description:RNA sequencing analysis of small RNA expression in sessile serrated adenoma/polyps, hyperplastic polyps, adenomatous polyps, uninvolved colon and control colon
2018-10-18 | GSE118504 | GEO
Project description:Sessile serrated adenomas are now recognized as precursor lesions of a substantial subset of colorectal cancers arising via a so-called “serrated pathway”. However, their biological markers remain to be defined. The aim of our study was to identify differentially expressed genes in sessile serrated adenomas, hyperplastic polyps and tubular adenomas. Gene expression analysis demonstrated molecular differences between polyp types. Further studies using QRT-PCR on Cathepsin E demonstrated a significantly (p< 0.05) higher expression in sessile serrated adenomas as compared to both other polyp types. Trefoil Factor 1, showed the same trend of expression for sessile serrated adenomas as compared to hyperplastic polyps, and was significantly higher in both polyps compared to tubular adenomas. Immunohistochemistry for both proteins demonstrated strong cytoplasmic staining of abnormal crypts in all sessile serrated adenomas while staining in tubular adenomas and hyperplastic polyps was weak and focal. BRAF and KRAS mutation analysis were employed to further validate polyp discrimination. The findings demonstrated the positive association of the BRAF mutation, V600E, with sessile serrated adenomas and KRAS mutations with tubular adenomas (P<0.05). This study demonstrates CTSE and TFF1 over-expression in sessile serrated adenomas compared to both hyperplastic polyps and tubular adenomas. Keywords: colonic polyp tissue comparison, linear modelling, SSA
2008-08-27 | GSE12514 | GEO
Project description:Screening and surveillance of colorectal cancers (CRCs) using advanced colonoscopy technologies have significantly reduced the incidence and mortality rates of CRCs in recent years. However, a significant portion of CRCs are still remained undiagnosed, especially those involving sessile serrated adenomas/polyps (SSA/P), most likely due to their flat shape and the excessive amounts of secreted mucin that cover the polyps, making them invisible for colonoscopy. Here, a potential alternative solution is the application of molecular markers enabling unambiguous characterization of SSPs. However, full implementation of this strategy requires availability of robust markers which are still lacking. In this work by comprehensive molecular analysis of several malignant and normal samples at the genome, methylome and transcriptome levels we show that activating mutation of BRAF-V600E drives the generation of a unique SSP-specific DNA methylation profile. As the result a robust set of DNA methylation markers showing significant (~3 to 30 fold) increase in their methylation levels, exclusively in SSP samples, are introduced. These markers can be of important clinical relevance, especially in early diagnosis of SSPs using non-invasive approaches such as fecal DNA testing.
2018-04-09 | GSE110537 | GEO
Project description:Screening and surveillance of colorectal cancers (CRCs) using advanced colonoscopy technologies have significantly reduced the incidence and mortality rates of CRCs in recent years. However, a significant portion of CRCs are still remained undiagnosed, especially those involving sessile serrated adenomas/polyps (SSA/P), most likely due to their flat shape and the excessive amounts of secreted mucin that cover the polyps, making them invisible for colonoscopy. Here, a potential alternative solution is the application of molecular markers enabling unambiguous characterization of SSPs. However, full implementation of this strategy requires availability of robust markers which are still lacking. In this work by comprehensive molecular analysis of several malignant and normal samples at the genome, methylome and transcriptome levels we show that activating mutation of BRAF-V600E drives the generation of a unique SSP-specific DNA methylation profile. As the result a robust set of DNA methylation markers showing significant (~3 to 30 fold) increase in their methylation levels, exclusively in SSP samples, are introduced. These markers can be of important clinical relevance, especially in early diagnosis of SSPs using non-invasive approaches such as fecal DNA testing.
2018-04-09 | GSE110536 | GEO
Project description:Screening and surveillance of colorectal cancers (CRCs) using advanced colonoscopy technologies have significantly reduced the incidence and mortality rates of CRCs in recent years. However, a significant portion of CRCs are still remained undiagnosed, especially those involving sessile serrated adenomas/polyps (SSA/P), most likely due to their flat shape and the excessive amounts of secreted mucin that cover the polyps, making them invisible for colonoscopy. Here, a potential alternative solution is the application of molecular markers enabling unambiguous characterization of SSPs. However, full implementation of this strategy requires availability of robust markers which are still lacking. In this work by comprehensive molecular analysis of several malignant and normal samples at the genome, methylome and transcriptome levels we show that activating mutation of BRAF-V600E drives the generation of a unique SSP-specific DNA methylation profile. As the result a robust set of DNA methylation markers showing significant (~3 to 30 fold) increase in their methylation levels, exclusively in SSP samples, are introduced. These markers can be of important clinical relevance, especially in early diagnosis of SSPs using non-invasive approaches such as fecal DNA testing.
2018-04-09 | GSE110535 | GEO
Project description:Sessile serrated colon adenoma/polyps (SSA/P) are found during routine screening colonoscopy and may account for 20% to 30% of colon cancers. However, differentiating SSA/Ps from hyperplastic polyps (HP) with little risk of cancer is challenging and complementary molecular markers are needed. In addition, the molecular mechanisms of colon cancer development from SSA/Ps are poorly understood. RNA sequencing (RNA-Seq) was performed on 21 SSA/Ps, 10 HPs, 10 adenomas, 21 uninvolved colon, and 20 control colon specimens. Differential expression and leave-one-out cross-validation methods were used to define a unique gene signature of SSA/Ps. Our SSA/P gene signature was evaluated in colon cancer RNA-Seq data from The Cancer Genome Atlas (TCGA) to identify a subtype of colon cancers that may develop from SSA/Ps. A total of 1,422 differentially expressed genes were found in SSA/Ps relative to controls. Serrated polyposis syndrome (n = 12) and sporadic SSA/Ps (n = 9) exhibited almost complete (96%) gene overlap. A 51-gene panel in SSA/P showed similar expression in a subset of TCGA colon cancers with high microsatellite instability. A smaller 7-gene panel showed high sensitivity and specificity in identifying BRAF-mutant, CpG island methylator phenotype high, and MLH1-silenced colon cancers. We describe a unique gene signature in SSA/Ps that identifies a subset of colon cancers likely to develop through the serrated pathway. These gene panels may be utilized for improved differentiation of SSA/Ps from HPs and provide insights into novel molecular pathways altered in colon cancer arising from the serrated pathway. Cancer Prev Res; 9(6); 456-65. ©2016 AACR.
| S-EPMC4941619 | biostudies-literature
Project description:In this study we compared gene expression of precancerous SSA/Ps and benign MVHPs with particular focus on genes involved in colorectal cancer. We also identify genes whose expression can be used to differentiate SSA/Ps and MVHPs. These results provide insight into the development of SSA/Ps and illustrates differences between these related colonic polyps. Total RNA from 6 samples of normal colon, 6 microvesicular hyperplastic polyps, and 6 sessile serrated adenomas/polyps were compared
2013-07-09 | E-GEOD-43841 | biostudies-arrayexpress
Project description:Sessile serrated adenomas are now recognized as precursor lesions of a substantial subset of colorectal cancers arising via a so-called “serrated pathway”. However, their biological markers remain to be defined. The aim of our study was to identify differentially expressed genes in sessile serrated adenomas, hyperplastic polyps and tubular adenomas. Gene expression analysis demonstrated molecular differences between polyp types. Further studies using QRT-PCR on Cathepsin E demonstrated a significantly (p< 0.05) higher expression in sessile serrated adenomas as compared to both other polyp types. Trefoil Factor 1, showed the same trend of expression for sessile serrated adenomas as compared to hyperplastic polyps, and was significantly higher in both polyps compared to tubular adenomas. Immunohistochemistry for both proteins demonstrated strong cytoplasmic staining of abnormal crypts in all sessile serrated adenomas while staining in tubular adenomas and hyperplastic polyps was weak and focal. BRAF and KRAS mutation analysis were employed to further validate polyp discrimination. The findings demonstrated the positive association of the BRAF mutation, V600E, with sessile serrated adenomas and KRAS mutations with tubular adenomas (P<0.05). This study demonstrates CTSE and TFF1 over-expression in sessile serrated adenomas compared to both hyperplastic polyps and tubular adenomas. Keywords: colonic polyp tissue comparison, linear modelling, SSA Microarray analysis was performed on 13 SSAs and 11 TAs. SSAs were from 4 males and 9 females (mean age of 75) and TAs were from 5 males and 6 females (mean age of 72). Samples were directly hybridised to each other (SSA versus TA) or to a pooled normal control (SSA versus control). A linear model (Smyth 2004) was fitted to the data bringing together the three contrasts: SSA versus control, TA versus control and SSA versus TA. Human OligoLibrary (Compugen Human Oligo Library (v1) containing 18861 60-mer oligonucleotides, representing approximately 16,000 unique genes) by the Adelaide Microarray Centre (Australia) was used. Slides were scanned using a GenePix 3000B scanner (Axon Instruments, Sunnydale, CA), and the Spot package (CSIRO, Australia) was used to identify spots and estimate fore- and background intensities (using a morphological opening background estimator) (Yang, Buckley et al. 2001; Ritchie 2004). Data analysis was performed in R (www.r-project.org) using the Limma package of Bioconductor (Gentleman, Carey et al. 2004; Smyth 2004). Loess print tip method was used to correct for dye-bias and intensity within each group of adjacent spots printed by one pin (Yang, Dudoit et al. 2002). Linear modelling was performed with the Limma package of Bioconductor (Smyth 2004).
2008-08-26 | E-GEOD-12514 | biostudies-arrayexpress