Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA147677 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:KRAS mutation is a negative predictive factor for treatment with anti-epidermal growth factor receptor (EGFR) antibodies in metastatic colorectal cancer (mCRC). Novel predictive markers are required to further improve the selection of patients for this treatment. Here, we assessed the influence of modification of KRAS by gene copy number aberration (CNA) and microRNAs (miRNAs) in correlation to clinical outcome in mCRC patients treated with cetuximab in combination with chemotherapy and bevacizumab. Formalin-fixed paraffin-embedded primary tumour tissue was used from 34 mCRC patients in a phase III trial, who were selected based upon their good (n=17) or poor (n=17) progression-free survival (PFS) upon treatment with cetuximab in combination with capecitabine, oxaliplatin, and bevacizumab. Gene copy number at the KRAS locus was assessed using high resolution genome-wide array CGH and the expression levels of 17 miRNAs targeting KRAS were determined by real-time PCR. Good response was associated with 12p12.1 copy number loss, even in patients with a KRAS mutation, while copy number gain in wild-type KRAS patients was correlated with a poor response. In KRAS mutated tumours increased miR-200b and decreased miR-143 expression were associated with a good response. In wild-type KRAS patients, miRNA expression did not predict response in a multivariate model. Thus, assessment of KRAS CNA and miRNAs targeting KRAS might further optimize the selection of patients eligible for anti-EGFR therapy. Copy number detection was performed using NimbleScan and Nexus software Formalin-fixed paraffin-embedded primary tumour tissue was used from 34 metastisized colorectal cancer patients in a phase III trial (CKTO 2005-02; ClinTrials.gov NCT00208546) of the Dutch Colorectal Cancer Group (DCCG), who were selected based upon their good (n=17) or poor (n=17) progression-free survival (PFS) upon treatment with cetuximab in combination with capecitabine, oxaliplatin, and bevacizumab.
2012-01-01 | E-GEOD-32048 | biostudies-arrayexpress
Project description:KRAS mutation is a negative predictive factor for treatment with anti-epidermal growth factor receptor (EGFR) antibodies in metastatic colorectal cancer (mCRC). Novel predictive markers are required to further improve the selection of patients for this treatment. Here, we assessed the influence of modification of KRAS by gene copy number aberration (CNA) and microRNAs (miRNAs) in correlation to clinical outcome in mCRC patients treated with cetuximab in combination with chemotherapy and bevacizumab. Formalin-fixed paraffin-embedded primary tumour tissue was used from 34 mCRC patients in a phase III trial, who were selected based upon their good (n=17) or poor (n=17) progression-free survival (PFS) upon treatment with cetuximab in combination with capecitabine, oxaliplatin, and bevacizumab. Gene copy number at the KRAS locus was assessed using high resolution genome-wide array CGH and the expression levels of 17 miRNAs targeting KRAS were determined by real-time PCR. Good response was associated with 12p12.1 copy number loss, even in patients with a KRAS mutation, while copy number gain in wild-type KRAS patients was correlated with a poor response. In KRAS mutated tumours increased miR-200b and decreased miR-143 expression were associated with a good response. In wild-type KRAS patients, miRNA expression did not predict response in a multivariate model. Thus, assessment of KRAS CNA and miRNAs targeting KRAS might further optimize the selection of patients eligible for anti-EGFR therapy. Copy number detection was performed using NimbleScan and Nexus software
2012-01-01 | GSE32048 | GEO
Project description:The aim of our study was to investigate whether miRNAs could serve as predictive biomarkers to anti-EGFR therapy (cetuximab, panitumumab) in patients with KRAS wild-type (wt-KRAS) metastatic colorectal cancer (mCRC). In our study, historical cohort of 96 patiens with wt-KRAS mCRC (2006-2009) was included and further divided into exploratory and validation cohorts. Large-scale miRNAs expression profiling was performed on the exploratory cohort of 41 wt-KRAS mCRC patients treated with cetuximab to identify miRNAs associated with time to progression (TTP). The validation was performed on two independent cohorts: 30 patients of wt-KRAS mCRC treated with cetuximab and 25 patients of wt-KRAS mCRC treated with panitumumab.
2016-05-05 | E-MTAB-3548 | biostudies-arrayexpress
Project description:Mutational status of KRAS in CRC is used to aid patient stratification for Cetuximab treatment. However, only a subset (10-40%) of patients with wt KRAS respond. We analyzed 40 mCRC tumors for Cetuximab response using a functional ex vivo platform. In the subset of non-responsive tumors, mutational (KRAS/BRAF and PIK3CA) and expression (AREG/EREG) analysis of key genes, transcriptomic profiling and GSEA were carried out to elucidate the molecular mechanisms underlying the response. Our analysis revealed deregulation of multiple pathways, notably Notch and Erbb2 and combined blockade of these two nodes elicited significant antitumor response. These findings collectively indicate the dependence of Cetuximab insensitive mCRC tumors on Notch and Erbb2 for survival and progression. 8 Primary tumors tested in ex vivo platform for response to Cetuximab were subjected to expression analysis
2014-04-01 | E-GEOD-56386 | biostudies-arrayexpress
Project description:We performed whole exome sequencing and copy number analysis for 15 triplets, each comprising normal colorectal tissue, primary colorectal carcinoma, and its synchronous matched liver metastasis. We analyzed the similarities and differences between primary colorectal carcinoma and matched liver metastases in regards to somatic mutations and somatic copy number alterationss (SCNAs). The genomic profiling demonstrated mutations in APC(73%), KRAS (33%), ARID1A and PIK3CA (6.7%) genes between primary colorectal and metastatic liver tumors. TP53 mutation was observed in 47% of the primary samples and 67% in liver metastatic samples. The grouped pairs, in hierarchical clustering showed similar SCNA patterns, in contrast to the ungrouped pairs. Many mutations (including those of known key cancer driver genes) were shared in the grouped pairs. The ungrouped pairs exhibited distinct mutation patterns with no shared mutations in key driver genes. Four ungrouped liver metastasis samples had mutations in DNA mismatch repair genes along with hypermutations and a substantial number of copy number of alterations. Genomically, colorectal and metastatic liver tumors were very similar. However, in a subgroup of patients, there were genetic variations in liver metastases in the loss of DNA mismatch repair genes. Copy number analysis of Affymetrix CytoScanHD arrays was performed for 15 primary colorectal carcinoma and 15 samples of their matched liver metastases. 15 normal samples prepared from each of the patient was used as the reference for the study. Nexus Copy number 6.1 software was used for somatic copy number alteration analysis.
2014-03-01 | E-GEOD-53799 | biostudies-arrayexpress
Project description:Mutational status of KRAS in CRC is used to aid patient stratification for Cetuximab treatment. However, only a subset (10-40%) of patients with wt KRAS respond. We analyzed 40 mCRC tumors for Cetuximab response using a functional ex vivo platform. In the subset of non-responsive tumors, mutational (KRAS/BRAF and PIK3CA) and expression (AREG/EREG) analysis of key genes, transcriptomic profiling and GSEA were carried out to elucidate the molecular mechanisms underlying the response. Our analysis revealed deregulation of multiple pathways, notably Notch and Erbb2 and combined blockade of these two nodes elicited significant antitumor response. These findings collectively indicate the dependence of Cetuximab insensitive mCRC tumors on Notch and Erbb2 for survival and progression.
2014-04-01 | GSE56386 | GEO
Project description:We performed whole exome sequencing and copy number analysis for 15 triplets, each comprising normal colorectal tissue, primary colorectal carcinoma, and its synchronous matched liver metastasis. We analyzed the similarities and differences between primary colorectal carcinoma and matched liver metastases in regards to somatic mutations and somatic copy number alterationss (SCNAs). The genomic profiling demonstrated mutations in APC(73%), KRAS (33%), ARID1A and PIK3CA (6.7%) genes between primary colorectal and metastatic liver tumors. TP53 mutation was observed in 47% of the primary samples and 67% in liver metastatic samples. The grouped pairs, in hierarchical clustering showed similar SCNA patterns, in contrast to the ungrouped pairs. Many mutations (including those of known key cancer driver genes) were shared in the grouped pairs. The ungrouped pairs exhibited distinct mutation patterns with no shared mutations in key driver genes. Four ungrouped liver metastasis samples had mutations in DNA mismatch repair genes along with hypermutations and a substantial number of copy number of alterations. Genomically, colorectal and metastatic liver tumors were very similar. However, in a subgroup of patients, there were genetic variations in liver metastases in the loss of DNA mismatch repair genes.
2014-03-01 | GSE53799 | GEO
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:Oncogenic KRAS mutations are absent in approximately 10% of patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) and may represent a subgroup of mPDAC with therapeutic options beyond standard-of-care cytotoxic chemotherapy. While distinct gene fusions have been implicated in KRAS wildtype mPDAC, information regarding other types of mutations remain limited, and gene expression patterns associated with KRAS wildtype mPDAC have not been reported. Here, we leverage sequencing data from the PanGen trial to perform comprehensive characterization of the molecular landscape of KRAS wildtype mPDAC and reveal increased frequency of chr1q amplification encompassing transcription factors PROX1 and NR5A2. By leveraging data from colorectal adenocarcinoma and cholangiocarcinoma samples, we highlight novel similarities between cholangiocarcinoma and KRAS wildtype mPDAC involving both mutation and expression-based signatures and validate these findings using an independent dataset. These data further establish KRAS wildtype mPDAC as a unique molecular entity, with therapeutic opportunities extending beyond gene fusion events.
2022-10-15 | PXD036632 | Pride
Project description:Although fine needle aspiration (FNA) cytology is helpful in determining whether thyroid nodules are benign or malignant, this distinction remains challenging in follicular neoplasms. Identification of genomic alterations in cytological specimens that distinguish between benign and malignant follicular tumors would have great clinical value. This study identified chromosomal imbalances in a set of 126 thyroid frozen follicular lesions characterized by histopathology, using aCGH, FISH, and DNA ploidy determination. An evaluation algorithm was developed based on a panel of three FISH experiments to better distinguish between follicular adenomas and carcinomas of the thyroid. This algorithm detects structural abnormalities that were observed in about half of the follicular thyroid carcinomas. These molecular markers may be therefore useful as an adjunct for making a differential diagnosis of follicular adenoma versus follicular carcinoma using cytological material obtained by FNA. Further information on the values in the comment columns: [FISH_1p_Loss : Status for abnormality found in terms of copy number variation for chr1p by FISH], [FISH_22_Loss : Status for abnormality found in terms of copy number variation for chr22 by FISH], [FISH_X_Gain : Status for abnormality found in terms of copy number variation for chrX by FISH], [FISH_Global : Status for abnormality found in terms of copy number variation for at least one of these (chr1p, chr22, chrX) by FISH], [DNA_Index : Measured by flow cytometry], [KRAS_Mutation : Mutation status for KRAS, obtained from Sanger sequencing. wt for wild-type, mut for mutant], [HRAS_Mutation : Mutation status for HRAS, obtained from Sanger sequencing. wt for wild-type, mut for mutant], [NRAS_Mutation : Mutation status for NRAS, obtained from Sanger sequencing. wt for wild-type, mut for mutant], [BRAF_Mutation : Mutation status for BRAF, obtained from Sanger sequencing. wt for wild-type, mut for mutant], [CTNNB1_Mutation : Mutation status for CTNNB1, obtained from Sanger sequencing. wt for wild-type, mut for mutant], [PIK3CA_Mutation : Mutation status for PIK3CA, obtained from Sanger sequencing. wt for wild-type, mut for mutant], [PAX8-PPARg_Fusion : Status for the PAX8-PPARG gene fusion, obtained from qRT-PCR. pos for presence of fusion, neg for absence], [RET-PTC_Fusion : Status for the RET-PTC gene fusion, obtained from qRT-PCR. pos for presence of fusion, neg for absence], [Mutation_Status : Global mutation status, combining results from HRAS, NRAS mutation status, and PAX8-PPARG fusion status], [Tumor_Size_cm : Tumor size in centimeters], [pT : Classes defined according to the size of the tumors (for more information, check AJCC classification)], [pN : Classes defined according to the number of nodes involved or not (for more information, check AJCC classification)], [pM : Classes defined according to the presence or absence of distant metastases (for more information, check AJCC classification)], [Carcinoma_Histo_Type : Histological type for carcinoma. MIF for minimally invasive, WIF for widely invasive], [Adenoma_Histo_Type : Histological type for adenoma. MIC for microvesicular, MAC for macrovesicular, BOTH for both], [Follow-up_month : Patient follow-up in months], [Alive_status : Patient alive status. yes for alive patient, no for deceased patient], [Metastasis_status : Presence of metastasis during the follow-up. yes for positive, no for negative, possible when uncertainty remains].
2013-07-01 | E-MTAB-1575 | biostudies-arrayexpress