Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA243086 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Anti-EGFR antibodies are effective in therapies for late-stage colorectal cancer (CRC); however, many tumours are unresponsive or develop resistance. We performed genomic analysis of intrinsic and acquired resistance to anti-EGFR therapy in prospectively collected tumour samples from 25 CRC patients receiving cetuximab (an EGFR inhibitor). Of 25 CRC patients, 13 displayed intrinsic resistance to cetuximab; 12 were intrinsically sensitive. We obtained six re-biopsy samples at acquired resistance from the intrinsically sensitive patients. NCOA4–RET and LMNA–NTRK1 fusions and NRG1 and GNAS amplifications were found in intrinsic-resistant patients. In cetuximab-sensitive patients, we found KRAS K117N and A146T mutations in addition to BRAF V600E, AKT1 E17K, PIK3CA E542K, and FGFR1 or ERBB2 amplifications. The comparison between baseline and acquired-resistant tumours revealed an extreme shift in variant allele frequency of somatic variants, suggesting that cetuximab exposure dramatically selected for rare resistant subclones that were initially undetectable. There was also an increase in epithelial-to-mesenchymal transition at acquired resistance, with a reduction in the immune infiltrate. Furthermore, characterization of an acquired-resistant, patient-derived cell line showed that PI3K/mTOR inhibition could rescue cetuximab resistance. Thus, we uncovered novel genomic alterations that elucidate the mechanisms of sensitivity and resistance to anti-EGFR therapy in metastatic CRC patients.
2019-09-21 | E-MTAB-8340 | biostudies-arrayexpress
Project description:Cetuximab (Erbitux) is an antibody drug against EGFR and commonly used in late stage HNSCC and metastatic colorectal cancer. The oncogenic mutation of certain genes are known to drive Cetuximab resistance such as K-RAS or b-RAF mutation. The aberrant activation of signaling pathways in the presence of Cetuximab treatment to overcome cellular stress contribute to acquired resistance to Cetuximab as well. To better understand the mechanisms and molecular patterns of Cetuximab resistant cells, the Cetuximab resistant cells are trained for examining the gene expression profile. The gene expression array is used for identify the molecular signature governing the Cetuximab resitance.
2017-03-02 | GSE63916 | GEO
Project description:In this study we want present a bank of metastatic colorectal cancer (mCRC) Patient Derived Organoids (PDOs) obtained from Patient Derived Xenografts (PDXs). These models are annotated with different omics to advance our understanding of CRC. We wanted to create a resource for the scientific community to assess the predictive reliability of these preclinical models. We performed comparative analyses between PDOs and matched PDXs to assess the similarities of these two platforms regarding molecular profiles and transcriptional classification. Moreover, we analyzed how these models respond to Cetuximab, a chimeric monoclonal antibody, normally given to patients after chemotherapy, that inhibits EGFR. After having assessed models’ reliability with Cetuximab, we aimed at identifying potential synergistic drugs to individuate new possible therapeutic prospects.
2023-03-01 | GSE204805 | GEO
Project description:Colorectal cancer (CRC) patients suffer from the second highest mortality among all cancer entities. In half of all CRC patients, colorectal cancer liver metastases (CRLM) can be observed. Metastatic colorectal cancer is associated with poor overall survival and limited treatment options. Even after successful surgical resection of the primary tumor, metachronous liver metastases occur in one out of eight cases. The only available curative intended treatment is hepatic resection, but metachronous CRLM frequently recur after approximately one year. In this study, we performed a proteome analysis of three recurrent liver metastases of a single CRC patient by mass spectrometry. Despite surgical resection of the primary CRC and adjuvant chemotherapy plus cetuximab treatment, the patient developed three metachronous CRLM which occurred consecutively after 9, 21 and 31 months. We identified a set of 1,132 proteins expressed in the three metachronous CRLM, of which 481 were differentially regulated, including 81 proteins that were associated with the extracellular matrix (ECM). 56 ECM associated proteins were identified as upregulated in the third metastasis, 26 (46%) of which were previously described as negative prognostic markers in CRC, including tenascin C, nidogen 1, fibulin1 and vinculin. These data may reflect an ascending trend of malignancy from the first to the third metachronous colorectal cancer liver metastasis. Additionally, the results indicate different ECM phenotypes for recurrent metachronous metastasis, associated with different grades of malignancy and highlights the importance of individual analysis of molecular features in different, consecutive metastatic events in a single patient.
2021-09-09 | PXD020109 | Pride
Project description:We evaluated the profile of miRNA and snoRNA expression in 5 synchronous CRC and matched normal colorectal tissues using the Affymetrix GeneChip miRNA 1.0 array. A total of 24 miRNA differential expressed transcripts which represent 27 mature miRNAs, including an oncogenic miR-17-92a and oncosuppressive miR-143-145 cluster, and a global up-regulation of snoRNAs were revealed in cancer tissues compared with matched normal tissues. Global miRNA expression could distinguish synchronous cancer from normal mucosa. Our findings represent the first comprehensive miRNA and snoRNA expression signatures for synchronous CRC, which increase the understanding of the molecular basis of synchronous CRC, and firstly implicate that dysregulation of snoRNAs and miRNA clusters may present therapeutic targets for synchronous CRC. Examination of microRNA and snoRNA expression in synchronous CRC and matched normal colorectal tissues
2015-08-01 | E-GEOD-54632 | biostudies-arrayexpress
Project description:Despite identification of major genes and pathways involved in development of colorectal cancer (CRC) it became obvious that several steps in these pathways might be bypassed by other yet unknown genetic events that lead towards CRC. To improve our understanding of the genetic mechanisms of CRC development we used microarrays to identify novel genes involved in development of CRC. In order to identify possible novel genes involved in the development of colorectal cancer we analysed the expression profile of 16 colorectal cancers. We used dual color approach. Tumour tissue was labeled with Cy5 and corresponding normal tissue was labeled with Cy3. Each array contained at least 4 replicate spots for each gene analysed. Expression was obtained by calculating median from replicate spots. Genes not present in at least 100% of all samples were filtered out. Median value for each gene from 16 arrays was calculated.
2010-06-20 | E-GEOD-14010 | biostudies-arrayexpress
Project description:SPO11-promoted DNA double-strand breaks (DSBs) formation is a crucial step for meiotic recombination, and it is indispensable to detect the broken DNA ends accurately for dissecting the molecular mechanisms behind. Here, we report a novel technique, named DEtail-seq (DNA End tailing followed by sequencing), that can directly and quantitatively capture the meiotic DSB 3’ overhang hotspots at single-nucleotide resolution.
2023-01-08 | GSE154227 | GEO
Project description:Genome wide DNA methylation profiling of primary (PR) and liver metastasis (LM) colorectal cancer (CRC). The Illumina Infinium MethylationEPIC Beadchip was used to obtain DNA methylation profiles across approximately 850,000 CpGs in human and xenogratfs derived samples. Raw data were processed using R minfi package. The main goal of this study is to develop a methylation-based classifier and predictor for metastatic CRC (mCRC), in order to find specific patients stratification for anti-EGFR targeted therapy (cetuximab) and bring the promise to shed new light on the role of methylation in driving colorectal cancer progression in different groups of patients.
2023-01-31 | GSE208713 | GEO
Project description:Towards understanding breast cancer mechanisms to metastasize
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Project description:Mutated in Colorectal Cancer (MCC) is a candidate tumor suppressor gene reported to be somatically mutated in the inherited colorectal cancer (CRC) syndrome Familial Adenomatous Polyposis. Additionally, MCC deletion and loss-ofheterozygosity
have also been reported as a common event in human CRC. However,to date, more than 28 years since its discovery, the mechanisms by which MCC contributes to intestinal cancer development as well as its function during normal intestinal tissue homeostasis remain unknown.
2023-07-29 | PXD035614 | JPOST Repository