Project description:Chromosomal instability (CIN) is the hallmark of colorectal adenoma to carcinoma progression in 85% of cases, with 20q gain as the most prominent aberration. Yet, the oncogenes at this chromosomal gain are still largely unknown. Here, we aimed to identify oncogenes at 20q involved in colorectal adenoma to carcinoma progression by measuring the effect of 20q gain on gene expression in this amplicon. Segmentation of DNA copy number changes on 20q was performed by array CGH in 67 colorectal adenomas and carcinomas. Additionally, robust analysis of mRNA expression in these segments was performed in 68 adenomas and carcinomas. This approach revealed seven genes to be important in CIN related adenoma to carcinoma progression. These genes may both serve as highly specific biomarkers for presence of high-risk precursor lesions as well as potential targets for pharmaceutical intervention. Keywords: Integration of array CGH and expression microarrays in colorectal cancer progression
Project description:Chromosomal instability (CIN) is the hallmark of colorectal adenoma to carcinoma progression in 85% of cases, with 20q gain as the most prominent aberration. Yet, the oncogenes at this chromosomal gain are still largely unknown. Here, we aimed to identify oncogenes at 20q involved in colorectal adenoma to carcinoma progression by measuring the effect of 20q gain on gene expression in this amplicon. Segmentation of DNA copy number changes on 20q was performed by array CGH in 67 colorectal adenomas and carcinomas. Additionally, robust analysis of mRNA expression in these segments was performed in 68 adenomas and carcinomas. This approach revealed seven genes to be important in CIN related adenoma to carcinoma progression. These genes may both serve as highly specific biomarkers for presence of high-risk precursor lesions as well as potential targets for pharmaceutical intervention. Keywords: Integration of array CGH and expression microarrays in colorectal cancer progression We performed array CGH on a panel of 41 progressed adenomas, from which the adenoma and carcinoma components were separately analysed (total, 82 samples). The DNA obtained from these samples was extracted from formalin-fixed, paraffin-embedded material. Additionally we analysed a series of independent frozen adenomas and carcinomas by array CGH (34 adenomas and 33 carcinomas) and expression microarrays (37 adenomas and 31 carcinomas). For array-CGH we used as reference DNA for all samples, a pool of 10 normal individuals. For expression microarrays we used as reference a commercial available RNA (pool of different cancer cell lines), from Strategene. No replicates nor dye swaps were done.
Project description:We established human colorectal tumor organoids from benign adenoma, primary colorectal cancer or metastasized colorectal cancer. The gene signature of tumor organoids associated with their tumor progression status. We also generated genome-edited organoids from human intestinal organoids recapitulating adenoma-carcinoma sequence. Gene expression signature of the genome engineered organoids were similar to that of adenoma organoids. This result indicated multiple (up to five) genetic mutations were insufficient for gene expression reprogramming of colorectal cancer. We used microarrays to detail the global program of gene expression in human colorectal tumor organoids and artificially mutation introduced organoids.
Project description:We established human colorectal tumor organoids from benign adenoma, primary colorectal cancer or metastasized colorectal cancer. The gene signature of tumor organoids associated with their tumor progression status. We also generated genome-edited organoids from human intestinal organoids recapitulating adenoma-carcinoma sequence. Gene expression signature of the genome engineered organoids were similar to that of adenoma organoids. This result indicated multiple (up to five) genetic mutations were insufficient for gene expression reprogramming of colorectal cancer. We used microarrays to detail the global program of gene expression in human colorectal tumor organoids and artificially mutation introduced organoids. To assess the expression profiling of genome-engineered organoids, we prepared total-RNA from cultured adenoma, carcinoma and genome-engineered organoids. We produced two types of genome-engineered organoids using the CRISPR/Cas9 or lentivirus vector system. Each engineered gene and engineered methods are described as a single alphabet and method name, respectively, in the sample characteristics field. The abbreviations for the engineered genes are as follows. 1) Genome-engineered organoids with CRISPR/Cas9 A = APC deletion; K = KRAS G12V knock in; S = Smad4 deletion; T = TP53 deletion; P = PIK3CA E545K knock in. 2) Genome-engineered organoids with Lent virus vector B = CTNNB1 S33Y overexpression; K = KRAS G12V overexpression; S = Smad4 shRNA overexpression; T = TP53 shRNA overexpression; P = PIK3CA E545K overexpression.
Project description:The colorectal adenoma-carcinoma sequence describes the stepwise progression from normal to dysplastic epithelium and then to carcinoma; only a small proportion of colorectal adenoma (CRA) progresses to colorectal carcinoma (CRC). Presently, endoscopic intervention is used on patients with CRAs of high grade dysplasia, diameters > 1 cm, or villous components > 25% who are at higher risk than other CRA sufferers. During the process, biopsy samples were taken for conventional histological diagnosis, but poor pathomorphological sensitivity and specificity greatly limit the diagnostic accuracy. Unfortunately, there are no reliable molecular criteria available that can predict the potential development of CRA to CRC. In present study, we use microarrays to detail the global programme of gene expression underlying the gradual progress of colorectal adenoma-carcinoma sequence.
Project description:Approximately two decades ago, Vogelstein and Fearon proposed the adenoma-carcinoma sequence of sporadic CRC development and illustrated the accumulation of genetic alterations during the stepwise progression, thereby providing a guideline for clinical practice. Although the detection and excision of precancerous lesions could prevent colorectal cancer and reduce mortality, 6% of adenomas will ultimately develop into colorectal cancer. Thus, this genetic model for colorectal tumorigenesis may not completely reflect the complex essence of the disease and whether the mode of initiation of the events in the multistep progression affects the outcome of CRC is still unknown. In this study, mRNA and miRNA expression profiling was performed with human colorectal tissues, including normal mucosa, adenoma and adenocarcinoma. Then, an integrated approach was adopted to establish the regulatory interaction networks that were correlated with colorectal carcinogenesis. Finally, a 55-gene signature whose expression was down-regulated in precancerous lesions compared to normal tissue was identified as a potential early indicator of CRC survival. The results suggested that genes related to immunity and homeostasis played a critical role in protection against adenoma initiation and that the altered molecular events that influence colorectal cancer prognosis may be set in an early, precancerous stage. Four types of human colorectal tissues were selected by colonoscopic resection or colorectal surgery, including 12 normal mucosae, 21 low-grade adenomas (mild or moderate atypical hyperplasia), 30 high-grade adenomas (severe atypical hyperplasia or carcinoma in situ) and 25 adenocarcinomas. Gene expression profiling analysis of these samples was performed using Agilent 4x44K human whole genome gene expression microarray (G4112F).
Project description:Approximately two decades ago, Vogelstein and Fearon proposed the adenoma-carcinoma sequence of sporadic CRC development and illustrated the accumulation of genetic alterations during the stepwise progression, thereby providing a guideline for clinical practice. Although the detection and excision of precancerous lesions could prevent colorectal cancer and reduce mortality, 6% of adenomas will ultimately develop into colorectal cancer. Thus, this genetic model for colorectal tumorigenesis may not completely reflect the complex essence of the disease and whether the mode of initiation of the events in the multistep progression affects the outcome of CRC is still unknown. In this study, mRNA and miRNA expression profiling was performed with human colorectal tissues, including normal mucosa, adenoma and adenocarcinoma. Then, an integrated approach was adopted to establish the regulatory interaction networks that were correlated with colorectal carcinogenesis. Finally, a 55-gene signature whose expression was down-regulated in precancerous lesions compared to normal tissue was identified as a potential early indicator of CRC survival. The results suggested that genes related to immunity and homeostasis played a critical role in protection against adenoma initiation and that the altered molecular events that influence colorectal cancer prognosis may be set in an early, precancerous stage. Four types of human colorectal tissues were selected by colonoscopic resection or colorectal surgery, including 15 normal mucosae, 39 low-grade adenomas (mild or moderate atypical hyperplasia), 20 high-grade adenomas (severe atypical hyperplasia or carcinoma in situ) and 33 adenocarcinomas. MicroRNA expression profiling analysis of these samples was performed on Agilent 8Ã16K Human miRNA Microarray V3 (G4470C).
Project description:Colorectal cancer often develops slowly from adenoma. In this study, we aimed to identify the oncogenes involved in the progression of colorectal adenoma to carcinoma by Tandem Mass Tag (TMT)-based quantitative proteomics. Protein expression changes were compared by TMT-based quantitative mass spectrometry in seven paired samples of normal mucosa, adenoma and carcinoma. Moreover, a bioinformatics analysis of differential protein expression was performed to screen for oncogenes. Effects of oncogene knockdown on cell viability, proliferation, migration and invasion were analyzed in colorectal cancer cell lines. Effects of oncogene overexpression on cell viability and proliferation were analyzed in adenoma organoids. The protein UTP18 was consistently upregulated in the normal-adenoma-carcinoma sequence. UTP18 downregulation was shown to inhibit colorectal cancer cell viability, proliferation, migration and invasion. UTP18 overexpression promoted adenoma organoid viability and proliferation. UTP18 facilitated the expression of MYC and impaired expression of the tumor-suppressor p21. Our data revealed the importance of UTP18 as an effector in the progression of adenoma to carcinoma. Thus, UTP18 is implicated as a highly specific biomarker for early diagnosis of progressive adenomas.
Project description:In the carcinogenesis of colorectal cancer (CRC), the stepwise progression from adenoma to carcinoma is marked by a series of specific genetic alterations of known oncogenes and tumor suppressor genes. However, many patient-matched features of the transcriptome involved in the adenoma-carcinoma sequence remain unidentified. The aim of this study was to identify genes associated with the process of CRC formation by analyzing the characteristics of the transcriptome during tumor formation. Six dynamic expression patterns specific to tumor formation were characterized for the first time. Dysregulation of metabolic pathways, suppression of the immune system, and activation of canonical pathways related to cancer were associated with the adenoma-carcinoma sequence. Among a cluster of genes positively correlated with tumor formation, TPD52L1 was identified as a gene that induced oncologic behaviors and a biomarker for poor prognosis.
Project description:Approximately two decades ago, Vogelstein and Fearon proposed the adenoma-carcinoma sequence of sporadic CRC development and illustrated the accumulation of genetic alterations during the stepwise progression, thereby providing a guideline for clinical practice. Although the detection and excision of precancerous lesions could prevent colorectal cancer and reduce mortality, 6% of adenomas will ultimately develop into colorectal cancer. Thus, this genetic model for colorectal tumorigenesis may not completely reflect the complex essence of the disease and whether the mode of initiation of the events in the multistep progression affects the outcome of CRC is still unknown. In this study, mRNA and miRNA expression profiling was performed with human colorectal tissues, including normal mucosa, adenoma and adenocarcinoma. Then, an integrated approach was adopted to establish the regulatory interaction networks that were correlated with colorectal carcinogenesis. Finally, a 55-gene signature whose expression was down-regulated in precancerous lesions compared to normal tissue was identified as a potential early indicator of CRC survival. The results suggested that genes related to immunity and homeostasis played a critical role in protection against adenoma initiation and that the altered molecular events that influence colorectal cancer prognosis may be set in an early, precancerous stage.