Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA277301 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The genome-wide miRNA expression analysis was performed in clinical samples, comprising 15 BRAF-mutant and 15 non-KRAS/BRAF-mutant colorectal cancers by using a SurePrint G3 Human miRNA microarray. clinical samples, comprising 15 BRAF-mutant and 15 non-KRAS/BRAF-mutant colorectal cancers by using a SurePrint G3 Human miRNA microarray.
2016-04-01 | E-GEOD-66548 | biostudies-arrayexpress
Project description:Despite advances in the detection and management of colorectal cancers, resistance to anti-cancer therapies remains a significant challenge. Activating mutations in KRAS and BRAF are frequently observed in colorectal cancers and have been associated with aggressive tumors and poor survival after chemotherapy. In the present study, we demonstrate that mutations in KRAS/BRAF alter the enhancer landscape of tumor cells, which leads to the resistance of the cornerstone colorectal cancer chemotherapeutic agent 5-fluorouracil (5-FU) through activation of transcription factor GATA1. Targeted inhibition of GATA1 reverses epigenetic changes in KRAS mutant cells and restores sensitivity to 5-FU. These results indicate a novel therapeutic opportunity for tailoring individualized therapy in human colorectal cancer.
2019-10-01 | GSE115400 | GEO
Project description:Background: The Ras pathway genes KRAS, BRAF or ERBBs have somatic mutations in ~60% of human colorectal carcinomas. At present, it is unknown whether the remaining cases lack mutations activating the Ras pathway, or whether they have acquired mutations in genes hitherto not known to belong to the pathway. Methods: To address the second possibility, and extend the compendium of Ras pathway genes, we used genome-wide transposon mutagenesis of two human colorectal cancer cell systems deprived of their activating KRAS or BRAF allele to identify genes enabling growth in low glucose, a Ras pathway phenotype, when targeted. Results: Of the 163 recurrently targeted genes in the two different genetic backgrounds, one third were known cancer genes and one-fifth had links to the EGFR/Ras/MAPK pathway. When compared to cancer genome sequencing datasets, 9 genes also mutated in human colorectal cancers were identified. Among these, stable knock-down of FOXO3, NCOA3, and TCF7L2 restored growth in low glucose but reduced MEK/MAPK phosphorylation, reduced anchorage-independent growth, and modulated expressions of GLUT1 and Ras pathway related proteins. Knock-down of NCOA3 and FOXO3 significantly decreased the sensitivity to cetuximab of KRAS mutant but not wild-type cells. Conclusions: This work establishes a proof-of-concept that human cell based genome-wide forward genetic screens can assign genes to pathways with clinical importance in human colorectal cancer.
2018-02-20 | PXD008382 | Pride
Project description:The genome-wide miRNA expression analysis was performed in clinical samples, comprising 15 BRAF-mutant and 15 non-KRAS/BRAF-mutant colorectal cancers by using a SurePrint G3 Human miRNA microarray.
2016-04-01 | GSE66548 | GEO
Project description:BRAF mutant colorectal cancer has a poor prognosis and gets resistant to BRAF inhibitors quickly. This study aims to clarify the mechanism of resistance to BRAFi. We found MCU1-C is overexpressed in BRAF mutant colorectal cancer and targeting MUC1-C genetically and pharmacologically sensitized Colorectal cancer cells to BRAF inhibitor. This finding suggests that MUC1-C could be a new therapeutic target for BRAF mutant colorectal cancer.
2022-11-30 | GSE215849 | GEO
Project description:A collection of genetically engineered mouse models (GEMM) of colorectal cancer (CRC) were created, and primary tumors from these GEMMs were analyzed. Primary CRC tumors from these GEMMs were genotyped to confirm that they contain the core genetic lesions of interest, including APC, P53, KRAS, and BRAF. Primary tumors from GEMMs with combinations of lesions of interest were analyzed by whole genome expression, and their expression profiles were compared to determine how they segregate. Signatures were then generated from GEMM tumors of interest and compared to human clinical datasets with expression and outcome data. Primary tumors from CRC GEMMs with different combinations of mutant alleles of interested were generated and analyzed. Alleles include mutant forms of APC (A), P53 (P), KRAS (K) and BRAF (B).
2014-07-01 | E-GEOD-50794 | biostudies-arrayexpress
Project description:Tumor cells carrying KRAS mutations activate the NF-?B pathway by different mechanisms, which contribute to the acquisition of essential cancer properties. The BRAF kinase, a downstream mediator of KRAS, is also mutated in a subset of colorectal cancers (CRC), which predicts bad prognosis and therapy resistance. However, nothing is known on whether NF-?B participates of BRAF-mediated tumorigenesis. We here found that in CRC cells, mutant BRAF does not trigger canonical or alternative NF-?B signaling but induces p45-IKK? activation. Moreover, IKK? activity is required for BRAF-induced transformation and to support BRAF-dependent transcription in CRC cells. Activation of p45-IKK? downstream of BRAF requires the TAK1 kinase, and is associated to the endosomal compartment. Inhibition of endosomal V-ATPase abolished p45-IKK? phosphorylation, and induced apoptosis of BRAF mutated CRC cells. Pharmacologic inhibition of endosome acidification reduced the in vivo growth of tumors carrying mutant BRAF, and abrogated the metastatic capacity of a primary human CRC tumor with acquired resistance to standard chemotherapy in an orthotopic xenograft model. 18 samples were analyzed: HT29 controls (n=3); HT28 BRAF inhibited (n=3), WiDr controls (n=3); WiDr BRAF inhibited (n=3); WiDr transduced with control shRNA (n=3) and WiDr transduced with shRNA against IKKalpha (n=3)
2015-05-08 | E-GEOD-57979 | biostudies-arrayexpress
Project description:Mutations activating the KRAS GTPase or the BRAF kinase are frequent in colorectal cancer and are thought to constitutively activate the terminal mitogen-activated protein kinase, ERK. Using mass cytometry, we found graded phosphorylation of ERK anti-correlated with cell differentiation in patient-derived colorectal cancer organoids, and unexpectedly this gradient was observed independently of KRAS mutational status. We therefore investigated differentiation-dependent signal transduction elicited by oncogenic KRAS or BRAF in transgenic mouse organoid models. Reporter, single cell transcriptome and mass cytometry analyses showed that transgenic expression of KRASG12V activated ERK in a cell type-specific pattern. Furthermore, expression of oncogenic KRAS induced the formation of RAS-ERK-responsive cells. In contrast, transgenic expression of BRAFV600E triggered high ERK activity and downstream gene expression in all intestinal cell types, followed by epithelial disorganisation. We analysed signal transduction to ERK using single cell-resolved network perturbation data in transgenic organoids. Network reconstruction followed by quantitative modelling revealed that activation of ERK is shaped by cell type-specific MEK to ERK feed forward and negative feedback signalling. We identify dual-specificity phosphatases as candidate modulators of MEK to ERK signal transduction. Our experiments highlight key differences between ERK activity elicited by the BRAF or KRAS oncogenes in colorectal cancer and find unexpected functional heterogeneity in a signalling pathway with fundamental relevance for cancer therapy.
2019-03-31 | GSE115242 | GEO
Project description:Tumor cells carrying KRAS mutations activate the NF-κB pathway by different mechanisms, which contribute to the acquisition of essential cancer properties. The BRAF kinase, a downstream mediator of KRAS, is also mutated in a subset of colorectal cancers (CRC), which predicts bad prognosis and therapy resistance. However, nothing is known on whether NF-κB participates of BRAF-mediated tumorigenesis. We here found that in CRC cells, mutant BRAF does not trigger canonical or alternative NF-κB signaling but induces p45-IKKα activation. Moreover, IKKα activity is required for BRAF-induced transformation and to support BRAF-dependent transcription in CRC cells. Activation of p45-IKKα downstream of BRAF requires the TAK1 kinase, and is associated to the endosomal compartment. Inhibition of endosomal V-ATPase abolished p45-IKKα phosphorylation, and induced apoptosis of BRAF mutated CRC cells. Pharmacologic inhibition of endosome acidification reduced the in vivo growth of tumors carrying mutant BRAF, and abrogated the metastatic capacity of a primary human CRC tumor with acquired resistance to standard chemotherapy in an orthotopic xenograft model.
2015-05-08 | GSE57979 | GEO
Project description:Mutant KRAS activates cancer stem cells (CSCs) contributing transformation of colorectal cancer (CRC) cells harboring adenomatous polyposis coli (APC) mutations. The factors mediating activation of CSCs by KRAS mutation were systematically investigated through a microarray analysis of the APC-mutated isogenic DLD-1 CRC cells harboring homogeneous wild-type KRAS (D-WT) or mutant KRAS (D-MT). The objective of the study was to find the factors specifically induced in the spheroids harboring both APC and KRAS mutations.
2019-10-16 | GSE119197 | GEO