Project description:Primary uveal melanomas show multiple genetic alterations. To determine mutational status of six human primary uveal melanomas, we performed whole exome sequencing (WES) and called Single Nucleotide Polimorphism (SNPs) to identify somatic mutations in these human primary uveal melanomas.
Project description:The incidence of esophageal adenocarcinoma (EAC) has risen 600% over the last 30 years. With an extremely poor five-year survival rate of only 15%, identification of new therapeutic targets for EAC is of great importance. Here, we analyze the mutation spectra from the whole exome sequencing of 149 EAC tumors/normal pairs, 15 of which have also been subjected to whole genome sequencing. We identify a novel mutational signature in EACs defined by a high prevalence of A to C transversions at Ap*A dinucleotides. Statistical analysis of the exome data identified 26 genes that are mutated at a significant frequency. Of these 26 genes, only four (TP53, CDKN2A, SMAD4, and PIK3CA) have been previously implicated in EAC. The novel significantly mutated genes include several chromatin modifying factors and candidate contributors to EAC: SPG20, TLR4, ELMO1, and DOCK2. Notably, functional analyses of EAC-derived mutations in ELMO1 increase cellular invasion. Therefore, we suggest a new hypothesis about the potential activation of the RAC1 pathway to be a contributor to EAC tumorigenesis. The study aimed to analyze 150 primary, human esophageal adenocarcinoma samples by whole genome and whole exome sequencing (which will be deposited to dbGAP following the TCGA practice). RNA expression data was used to determine gene expression in 14 of the samples analyzed by whole genome sequencing. No normals were analyzed.
Project description:Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17) leading to formation of PML-RARA fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, while mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large scale activation of gene expression and reduced in vitro differentiation potential. Studying the effects of silensing ARID1B gene in NB4 cell lines
Project description:With the whole genome SNP array information obtained from tumor and matched normal control, we could evaluate the acquired copy number alterations (CNAs) and uniparental disomies (UPDs) . Here we identified somatic mutations by whole-exome sequencing in 25 NKTCL patients and extended validation through targeted sequencing in an additional 80 cases.
Project description:<p>The purpose of this study was to identify somatic (tumor-specific) mutations in advanced stage endometrioid endometrial carcinoma tumor exomes. The dataset was generated at the NIH Intramural Sequencing Center (NISC) and NHGRI by next generation sequencing the exomes of 19 de-identified primary tumor DNAs, from advanced stage tumors, and matched non-tumor DNAs.</p>
Project description:The incidence of esophageal adenocarcinoma (EAC) has risen 600% over the last 30 years. With an extremely poor five-year survival rate of only 15%, identification of new therapeutic targets for EAC is of great importance. Here, we analyze the mutation spectra from the whole exome sequencing of 149 EAC tumors/normal pairs, 15 of which have also been subjected to whole genome sequencing. We identify a novel mutational signature in EACs defined by a high prevalence of A to C transversions at Ap*A dinucleotides. Statistical analysis of the exome data identified 26 genes that are mutated at a significant frequency. Of these 26 genes, only four (TP53, CDKN2A, SMAD4, and PIK3CA) have been previously implicated in EAC. The novel significantly mutated genes include several chromatin modifying factors and candidate contributors to EAC: SPG20, TLR4, ELMO1, and DOCK2. Notably, functional analyses of EAC-derived mutations in ELMO1 increase cellular invasion. Therefore, we suggest a new hypothesis about the potential activation of the RAC1 pathway to be a contributor to EAC tumorigenesis.
Project description:We leveraged massively parallel sequencing approach to comprehensively characterize the spectrum of somatic mutations and genomic rearrangements in two intestinal-type gastric adenocarcinomas from patients with and without active Helicobacter pylori infections. The tumours exhibited distinct patterns of genomic changes with more than 16,000 somatic substitutions on average, focal amplifications and rearrangements in the non-active infected tumour and a 7-fold enrichment of micro-deletions in the infected tumour. Paired-end sequences from large insert libraries revealed the structure and origins of large amplicons, including one involving the oncogene KRAS. The mutational frequencies of the tumours revealed patterns of H. pylori infection and mutagenesis and a unique exome signature, providing insights into mechanisms that define the mutational landscape of gastric cancer. For the tumour with active infection, we also reconstructed the genome of the pathogenic H. pylori strain from the raw sequence reads, demonstrating the power of whole-genome shotgun sequencing for simultaneously characterizing the tumour and its associated carcinogen genome.
Project description:Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17) leading to formation of PML-RARA fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, while mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large scale activation of gene expression and reduced in vitro differentiation potential.
Project description:The impact of different carcinogenic exposures on the specific patterns of somatic mutations in human tumors remains unclear. To clarify this issue, we profiled 209 cholangiocarcinomas (CCAs) from Asia and Europe, including 108 cases caused by liver fluke Opisthorchis viverrini (OV)-infection and 101 cases due to non-OV etiologies. Whole-exome (N = 15) and prevalence screening (N = 194) revealed recurrent somatic mutations in BAP1 and ARID1A, neither of which has been previously reported to be mutated in CCA. Comparisons between intrahepatic OV and non-OV CCAs demonstrated statistically significant different mutation patterns: BAP1 and IDH1/2 were more frequently mutated in non-OV CCAs, while TP53 displayed the reciprocal pattern. Functional studies demonstrated tumor suppressive roles of BAP1 and ARID1A, establishing the role of chromatin modulators in CCA pathogenesis. These findings indicate that different causative etiologies may induce distinct somatic alterations even within the same tumor type. Illumina 450k methylation array profiling performed on wild-type (n=23) and mutant (n=9) CCA (cholangiocarcinoma) samples, with adjacent normal tissue (n=4)