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Clinical Implementation of Integrated Genomic Profiling in Patients with Advanced Cancers. Sci Rep 2016; 6:25. [PMID: 28003660 PMCID: PMC5431338 DOI: 10.1038/s41598-016-0021-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 11/02/2016] [Indexed: 12/20/2022] Open
Abstract
DNA focused panel sequencing has been rapidly adopted to assess therapeutic targets in advanced/refractory cancer. Integrated Genomic Profiling (IGP) utilising DNA/RNA with tumour/normal comparisons in a Clinical Laboratory Improvement Amendments (CLIA) compliant setting enables a single assay to provide: therapeutic target prioritisation, novel target discovery/application and comprehensive germline assessment. A prospective study in 35 advanced/refractory cancer patients was conducted using CLIA-compliant IGP. Feasibility was assessed by estimating time to results (TTR), prioritising/assigning putative therapeutic targets, assessing drug access, ascertaining germline alterations, and assessing patient preferences/perspectives on data use/reporting. Therapeutic targets were identified using biointelligence/pathway analyses and interpreted by a Genomic Tumour Board. Seventy-five percent of cases harboured 1–3 therapeutically targetable mutations/case (median 79 mutations of potential functional significance/case). Median time to CLIA-validated results was 116 days with CLIA-validation of targets achieved in 21/22 patients. IGP directed treatment was instituted in 13 patients utilising on/off label FDA approved drugs (n = 9), clinical trials (n = 3) and single patient IND (n = 1). Preliminary clinical efficacy was noted in five patients (two partial response, three stable disease). Although barriers to broader application exist, including the need for wider availability of therapies, IGP in a CLIA-framework is feasible and valuable in selection/prioritisation of anti-cancer therapeutic targets.
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Comprehensive Genomic Analysis of Metastatic Mucinous Urethral Adenocarcinoma Guides Precision Oncology Treatment: Targetable EGFR Amplification Leading to Successful Treatment With Erlotinib. Clin Genitourin Cancer 2016; 15:e727-e734. [PMID: 28057415 PMCID: PMC7513310 DOI: 10.1016/j.clgc.2016.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 11/20/2016] [Indexed: 11/29/2022]
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An integrated framework for reporting clinically relevant biomarkers from paired tumor/normal genomic and transcriptomic sequencing data in support of clinical trials in personalized medicine. PACIFIC SYMPOSIUM ON BIOCOMPUTING. PACIFIC SYMPOSIUM ON BIOCOMPUTING 2015:56-67. [PMID: 25592568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The ability to rapidly sequence the tumor and germline DNA of an individual holds the eventual promise of revolutionizing our ability to match targeted therapies to tumors harboring the associated genetic biomarkers. Analyzing high throughput genomic data consisting of millions of base pairs and discovering alterations in clinically actionable genes in a structured and real time manner is at the crux of personalized testing. This requires a computational architecture that can monitor and track a system within a regulated environment as terabytes of data are reduced to a small number of therapeutically relevant variants, delivered as a diagnostic laboratory developed test. These high complexity assays require data structures that enable real-time and retrospective ad-hoc analysis, with a capability of updating to keep up with the rapidly changing genomic and therapeutic options, all under a regulated environment that is relevant under both CMS and FDA depending on application. We describe a flexible computational framework that uses a paired tumor/normal sample allowing for complete analysis and reporting in approximately 24 hours, providing identification of single nucleotide changes, small insertions and deletions, chromosomal rearrangements, gene fusions and gene expression with positive predictive values over 90%. In this paper we present the challenges in integrating clinical, genomic and annotation databases to provide interpreted draft reports which we utilize within ongoing clinical research protocols. We demonstrate the need to retire from existing performance measurements of accuracy and specificity and measure metrics that are meaningful to a genomic diagnostic environment. This paper presents a three-tier infrastructure that is currently being used to analyze an individual genome and provide available therapeutic options via a clinical report. Our framework utilizes a non-relational variant-centric database that is scaleable to a large amount of data and addresses the challenges and limitations of a relational database system. Our system is continuously monitored via multiple trackers each catering differently to the diversity of users involved in this process. These trackers designed in analytics web-app framework provide status updates for an individual sample accurate to a few minutes. In this paper, we also present our outcome delivery process that is designed and delivered adhering to the standards defined by various regulation agencies involved in clinical genomic testing.
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Whole genome sequencing reveals potential targets for therapy in patients with refractory KRAS mutated metastatic colorectal cancer. BMC Med Genomics 2014; 7:36. [PMID: 24943349 PMCID: PMC4074842 DOI: 10.1186/1755-8794-7-36] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 05/29/2014] [Indexed: 02/08/2023] Open
Abstract
Background The outcome of patients with metastatic colorectal carcinoma (mCRC) following first line therapy is poor, with median survival of less than one year. The purpose of this study was to identify candidate therapeutically targetable somatic events in mCRC patient samples by whole genome sequencing (WGS), so as to obtain targeted treatment strategies for individual patients. Methods Four patients were recruited, all of whom had received > 2 prior therapy regimens. Percutaneous needle biopsies of metastases were performed with whole blood collection for the extraction of constitutional DNA. One tumor was not included in this study as the quality of tumor tissue was not sufficient for further analysis. WGS was performed using Illumina paired end chemistry on HiSeq2000 sequencing systems, which yielded coverage of greater than 30X for all samples. NGS data were processed and analyzed to detect somatic genomic alterations including point mutations, indels, copy number alterations, translocations and rearrangements. Results All 3 tumor samples had KRAS mutations, while 2 tumors contained mutations in the APC gene and the PIK3CA gene. Although we did not identify a TCF7L2-VTI1A translocation, we did detect a TCF7L2 mutation in one tumor. Among the other interesting mutated genes was INPPL1, an important gene involved in PI3 kinase signaling. Functional studies demonstrated that inhibition of INPPL1 reduced growth of CRC cells, suggesting that INPPL1 may promote growth in CRC. Conclusions Our study further supports potential molecularly defined therapeutic contexts that might provide insights into treatment strategies for refractory mCRC. New insights into the role of INPPL1 in colon tumor cell growth have also been identified. Continued development of appropriate targeted agents towards specific events may be warranted to help improve outcomes in CRC.
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Integrated genomic characterization reveals novel, therapeutically relevant drug targets in FGFR and EGFR pathways in sporadic intrahepatic cholangiocarcinoma. PLoS Genet 2014; 10:e1004135. [PMID: 24550739 PMCID: PMC3923676 DOI: 10.1371/journal.pgen.1004135] [Citation(s) in RCA: 315] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 12/06/2013] [Indexed: 12/18/2022] Open
Abstract
Advanced cholangiocarcinoma continues to harbor a difficult prognosis and therapeutic options have been limited. During the course of a clinical trial of whole genomic sequencing seeking druggable targets, we examined six patients with advanced cholangiocarcinoma. Integrated genome-wide and whole transcriptome sequence analyses were performed on tumors from six patients with advanced, sporadic intrahepatic cholangiocarcinoma (SIC) to identify potential therapeutically actionable events. Among the somatic events captured in our analysis, we uncovered two novel therapeutically relevant genomic contexts that when acted upon, resulted in preliminary evidence of anti-tumor activity. Genome-wide structural analysis of sequence data revealed recurrent translocation events involving the FGFR2 locus in three of six assessed patients. These observations and supporting evidence triggered the use of FGFR inhibitors in these patients. In one example, preliminary anti-tumor activity of pazopanib (in vitro FGFR2 IC50≈350 nM) was noted in a patient with an FGFR2-TACC3 fusion. After progression on pazopanib, the same patient also had stable disease on ponatinib, a pan-FGFR inhibitor (in vitro, FGFR2 IC50≈8 nM). In an independent non-FGFR2 translocation patient, exome and transcriptome analysis revealed an allele specific somatic nonsense mutation (E384X) in ERRFI1, a direct negative regulator of EGFR activation. Rapid and robust disease regression was noted in this ERRFI1 inactivated tumor when treated with erlotinib, an EGFR kinase inhibitor. FGFR2 fusions and ERRFI mutations may represent novel targets in sporadic intrahepatic cholangiocarcinoma and trials should be characterized in larger cohorts of patients with these aberrations. Cholangiocarcinoma is a cancer that affects the bile ducts. Unfortunately, many patients diagnosed with cholangiocarcinoma have disease that cannot be treated with surgery or has spread to other parts of the body, thus severely limiting treatment options. New advances in drug treatment have enabled treatment of these cancers with “targeted therapy” that exploits an error in the normal functioning of a tumor cell, compared to other cells in the body, thus allowing only tumor cells to be killed by the drug. We sought to identify changes in the genetic material of cholangiocarcinoma patient tumors in order to identify potential errors in cellular functioning by utilizing cutting edge genetic sequencing technology. We identified three patient tumors possessing an FGFR2 gene that was aberrantly fused to another gene. Two of these patients were able to receive targeted therapy for FGFR2 with resulting tumor shrinkage. A fourth tumor contained an error in a gene that controls a very important cellular mechanism in cancer, termed epidermal growth factor pathway (EGFR). This patient received therapy targeting this mechanism and also demonstrated response to treatment. Thus, we have been able to utilize cutting edge technology with targeted drug treatment to personalize medical treatment for cancer in cholangiocarcinoma patients.
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A study of real-time CLIA-enabled whole genome tumor sequencing: Results for testicular cancer and sarcomatoid RCC. J Clin Oncol 2014. [DOI: 10.1200/jco.2014.32.4_suppl.463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
463 Background: The genomic assessment of cancer has been revolutionized by next-generation sequencing and is increasingly being applied in the clinic to guide therapeutic decision-making. Time to reporting of results, specimen quantity, and analyte quality have constrained initial clinical applications to gene panels and whole exome based strategies. Methods: Patients underwent surgical resection, excisional or core biopsies, or bone marrow biopsy. Samples were analyzed by whole genome or exome sequencing and RNA sequencing, bioinformatics analysis, and therapeutic target prioritization by a multi-disciplinary Clinical Genomics Board. All prioritized targets were CLIA validated using Sanger sequencing, RT-qPCR, FISH, or IHC as appropriate. Treatment was delivered using off-label FDA approved drugs, clinical trials, or single patient INDs. Results: We have enrolled 40 patients with advanced, treatment-refractory cancers of whom sequencing data is available on 33. The initial 6 patients were evaluated in a non-CLIA pilot phase and 27 in the CLIA enabled phase. Upon availability of the initial report, identified targets of putative therapeutic relevance were then prioritized by the CGB in 22/27 patients (81%) for subsequent CLIA validation. Eleven patients have been treated with genomically selected therapy with partial response in 3/10 assessed patients. A testicular cancer patient had aberrations in two testes specific genes, a copy number gain in TSSK6 and a novel gene fusion between thyroid hormone receptor associated protein 3 (THRAP3) and Tektin 2 (TEKT2). Additionally, a case of papillary renal cell carcinoma had an amplification of YAP1 and a previously unreported P287T mutation in CCND1, suggesting potential benefit with a CDK4/6 inhibitor. Treatment is ongoing and results will be reported. Conclusions: Integrated whole genome analysis in a CLIA setting is feasible. Integration of SNV, copy number and transcriptional data may allow for selection of putative driver genes to enhance targeted therapy decisions. Barriers for future broader implementation include the need for reduced time from biopsy to report and availability of therapies.
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A pilot study using next-generation sequencing in advanced cancers: feasibility and challenges. PLoS One 2013; 8:e76438. [PMID: 24204627 PMCID: PMC3813699 DOI: 10.1371/journal.pone.0076438] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 08/23/2013] [Indexed: 12/25/2022] Open
Abstract
PURPOSE New anticancer agents that target a single cell surface receptor, up-regulated or amplified gene product, or mutated gene, have met with some success in treating advanced cancers. However, patients' tumors still eventually progress on these therapies. If it were possible to identify a larger number of targetable vulnerabilities in an individual's tumor, multiple targets could be exploited with the use of specific therapeutic agents, thus possibly giving the patient viable therapeutic alternatives. EXPERIMENTAL DESIGN In this exploratory study, we used next-generation sequencing technologies (NGS) including whole genome sequencing (WGS), and where feasible, whole transcriptome sequencing (WTS) to identify genomic events and associated expression changes in advanced cancer patients. RESULTS WGS on paired tumor and normal samples from nine advanced cancer patients and WTS on six of these patients' tumors was completed. One patient's treatment was based on targets and pathways identified by NGS and the patient had a short-lived PET/CT response with a significant reduction in his tumor-related pain. To design treatment plans based on information garnered from NGS, several challenges were encountered: NGS reporting delays, communication of results to out-of-state participants and their treating oncologists, and chain of custody handling for fresh biopsy samples for Clinical Laboratory Improvement Amendments (CLIA) target validation. CONCLUSION While the initial effort was a slower process than anticipated due to a variety of issues, we demonstrate the feasibility of using NGS in advanced cancer patients so that treatments for patients with progressing tumors may be improved.
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Abstract 2023: Whole exome and RNA sequencing reveals genetic alterations in DNA damage and homologous recombination pathways in triple negative breast cancer. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Triple negative breast cancer (TNBC), is characterized by a lack of expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 (HER2). TNBC comprises about 15 of all breast cancer diagnoses, but ∼25% of deaths. TNBC has a more aggressive clinical course and long-term disease-free survival is poor. As is well known, tumors that develop in women who carry deleterious germline BRCA mutations typically have tumors characteristic of the basal-like TNBC phenotype associated with defects in double stand break repair and homologous recombination. These observations have led to the development of therapeutic strategies aimed at these mechanisms, such as PARP inhibitors, which are in mature stages of drug development for the treatment of a subset of patients diagnosed with mTNBC. Iniparib, although not believed to be a true PARP inhibitor, is believed to act through a similar mechanism of action.
We have completed a study of whole genome and transcriptome sequencing of 14 patients with metastatic triple negative breast cancer (mTNBC). One patient who was sequenced had a complete response to a combination including gemcitabine, carboplatin, and iniparib prior to sequencing. Sequencing analysis revealed a collection of somatic mutations and alterations in genes associated with DNA repair and homologous recombination, including DCLRE1C, MEI1, TP53, DDB1, RIF1, ZBTB40, BRIP1, and BRCA2. Furthermore, RNA-seq expression analysis demonstrated significant underexpression of BRCA1. Thus, these alterations may serve as markers that can be predictive of responders from non-responders of treatment regimens including iniparib or possibly PARP inhibitors.
To begin to identify a genomic profile indicative of PARP response, tumors and blood of four additional mTNBC patient samples were collected and subjected to whole exome and RNA sequencing. We have also obtained the mutational data of TNBC tumors sequenced by the Cancer Genome Atlas. The genetic profiles of these tumors will be compared to the previously sequence mTNBC sample that responded to iniparib to determine the frequency of these specific events in mTNBC. Through this work we hope to identify a genetic profile that can serve as a possible predictor of response to iniparib or true PARP inhibitors.
Citation Format: Shukmei Wong, Joyce A. O'Shaughnessy, Patricia LoRusso, Jessica Aldrich, Ahmet Kurdoglu, Alexis Christoforides, Jennifer Dinh, Tyler Izatt, Shripad Sinari, Angela Baker, Tracy M. Moses, Bodour Salhia, Spyro Mousses, Jeffrey Kiefer, Jeffrey M. Trent, Daniel Von Hoff, Geoffrey Shapiro, Winnie Liang, David W. Craig, John D. Carpten. Whole exome and RNA sequencing reveals genetic alterations in DNA damage and homologous recombination pathways in triple negative breast cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2023. doi:10.1158/1538-7445.AM2013-2023
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Genome and transcriptome sequencing in prospective metastatic triple-negative breast cancer uncovers therapeutic vulnerabilities. Mol Cancer Ther 2012; 12:104-16. [PMID: 23171949 DOI: 10.1158/1535-7163.mct-12-0781] [Citation(s) in RCA: 169] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Triple-negative breast cancer (TNBC) is characterized by the absence of expression of estrogen receptor, progesterone receptor, and HER-2. Thirty percent of patients recur after first-line treatment, and metastatic TNBC (mTNBC) has a poor prognosis with median survival of one year. Here, we present initial analyses of whole genome and transcriptome sequencing data from 14 prospective mTNBC. We have cataloged the collection of somatic genomic alterations in these advanced tumors, particularly those that may inform targeted therapies. Genes mutated in multiple tumors included TP53, LRP1B, HERC1, CDH5, RB1, and NF1. Notable genes involved in focal structural events were CTNNA1, PTEN, FBXW7, BRCA2, WT1, FGFR1, KRAS, HRAS, ARAF, BRAF, and PGCP. Homozygous deletion of CTNNA1 was detected in 2 of 6 African Americans. RNA sequencing revealed consistent overexpression of the FOXM1 gene when tumor gene expression was compared with nonmalignant breast samples. Using an outlier analysis of gene expression comparing one cancer with all the others, we detected expression patterns unique to each patient's tumor. Integrative DNA/RNA analysis provided evidence for deregulation of mutated genes, including the monoallelic expression of TP53 mutations. Finally, molecular alterations in several cancers supported targeted therapeutic intervention on clinical trials with known inhibitors, particularly for alterations in the RAS/RAF/MEK/ERK and PI3K/AKT/mTOR pathways. In conclusion, whole genome and transcriptome profiling of mTNBC have provided insights into somatic events occurring in this difficult to treat cancer. These genomic data have guided patients to investigational treatment trials and provide hypotheses for future trials in this irremediable cancer.
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Genome-wide characterization of pancreatic adenocarcinoma patients using next generation sequencing. PLoS One 2012; 7:e43192. [PMID: 23071490 PMCID: PMC3468610 DOI: 10.1371/journal.pone.0043192] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 07/19/2012] [Indexed: 12/24/2022] Open
Abstract
Pancreatic adenocarcinoma (PAC) is among the most lethal malignancies. While research has implicated multiple genes in disease pathogenesis, identification of therapeutic leads has been difficult and the majority of currently available therapies provide only marginal benefit. To address this issue, our goal was to genomically characterize individual PAC patients to understand the range of aberrations that are occurring in each tumor. Because our understanding of PAC tumorigenesis is limited, evaluation of separate cases may reveal aberrations, that are less common but may provide relevant information on the disease, or that may represent viable therapeutic targets for the patient. We used next generation sequencing to assess global somatic events across 3 PAC patients to characterize each patient and to identify potential targets. This study is the first to report whole genome sequencing (WGS) findings in paired tumor/normal samples collected from 3 separate PAC patients. We generated on average 132 billion mappable bases across all patients using WGS, and identified 142 somatic coding events including point mutations, insertion/deletions, and chromosomal copy number variants. We did not identify any significant somatic translocation events. We also performed RNA sequencing on 2 of these patients' tumors for which tumor RNA was available to evaluate expression changes that may be associated with somatic events, and generated over 100 million mapped reads for each patient. We further performed pathway analysis of all sequencing data to identify processes that may be the most heavily impacted from somatic and expression alterations. As expected, the KRAS signaling pathway was the most heavily impacted pathway (P<0.05), along with tumor-stroma interactions and tumor suppressive pathways. While sequencing of more patients is needed, the high resolution genomic and transcriptomic information we have acquired here provides valuable information on the molecular composition of PAC and helps to establish a foundation for improved therapeutic selection.
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Genome-wide characterization of pancreatic adenocarcinoma patients using next generation sequencing. PLoS One 2012. [PMID: 23071490 DOI: 10.137/journal.pone.0043192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Pancreatic adenocarcinoma (PAC) is among the most lethal malignancies. While research has implicated multiple genes in disease pathogenesis, identification of therapeutic leads has been difficult and the majority of currently available therapies provide only marginal benefit. To address this issue, our goal was to genomically characterize individual PAC patients to understand the range of aberrations that are occurring in each tumor. Because our understanding of PAC tumorigenesis is limited, evaluation of separate cases may reveal aberrations, that are less common but may provide relevant information on the disease, or that may represent viable therapeutic targets for the patient. We used next generation sequencing to assess global somatic events across 3 PAC patients to characterize each patient and to identify potential targets. This study is the first to report whole genome sequencing (WGS) findings in paired tumor/normal samples collected from 3 separate PAC patients. We generated on average 132 billion mappable bases across all patients using WGS, and identified 142 somatic coding events including point mutations, insertion/deletions, and chromosomal copy number variants. We did not identify any significant somatic translocation events. We also performed RNA sequencing on 2 of these patients' tumors for which tumor RNA was available to evaluate expression changes that may be associated with somatic events, and generated over 100 million mapped reads for each patient. We further performed pathway analysis of all sequencing data to identify processes that may be the most heavily impacted from somatic and expression alterations. As expected, the KRAS signaling pathway was the most heavily impacted pathway (P<0.05), along with tumor-stroma interactions and tumor suppressive pathways. While sequencing of more patients is needed, the high resolution genomic and transcriptomic information we have acquired here provides valuable information on the molecular composition of PAC and helps to establish a foundation for improved therapeutic selection.
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Cancer of the ampulla of Vater: analysis of the whole genome sequence exposes a potential therapeutic vulnerability. Genome Med 2012; 4:56. [PMID: 22762308 PMCID: PMC3580412 DOI: 10.1186/gm357] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 05/29/2011] [Accepted: 07/04/2012] [Indexed: 12/21/2022] Open
Abstract
Background Recent advances in the treatment of cancer have focused on targeting genomic aberrations with selective therapeutic agents. In rare tumors, where large-scale clinical trials are daunting, this targeted genomic approach offers a new perspective and hope for improved treatments. Cancers of the ampulla of Vater are rare tumors that comprise only about 0.2% of gastrointestinal cancers. Consequently, they are often treated as either distal common bile duct or pancreatic cancers. Methods We analyzed DNA from a resected cancer of the ampulla of Vater and whole blood DNA from a 63 year-old man who underwent a pancreaticoduodenectomy by whole genome sequencing, achieving 37× and 40× coverage, respectively. We determined somatic mutations and structural alterations. Results We identified relevant aberrations, including deleterious mutations of KRAS and SMAD4 as well as a homozygous focal deletion of the PTEN tumor suppressor gene. These findings suggest that these tumors have a distinct oncogenesis from either common bile duct cancer or pancreatic cancer. Furthermore, this combination of genomic aberrations suggests a therapeutic context for dual mTOR/PI3K inhibition. Conclusions Whole genome sequencing can elucidate an oncogenic context and expose potential therapeutic vulnerabilities in rare cancers.
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Paired tumor and normal whole genome sequencing of metastatic olfactory neuroblastoma. PLoS One 2012; 7:e37029. [PMID: 22649506 PMCID: PMC3359355 DOI: 10.1371/journal.pone.0037029] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 04/11/2012] [Indexed: 01/02/2023] Open
Abstract
Background Olfactory neuroblastoma (ONB) is a rare cancer of the sinonasal tract with little molecular characterization. We performed whole genome sequencing (WGS) on paired normal and tumor DNA from a patient with metastatic-ONB to identify the somatic alterations that might be drivers of tumorigenesis and/or metastatic progression. Methodology/Principal Findings Genomic DNA was isolated from fresh frozen tissue from a metastatic lesion and whole blood, followed by WGS at >30X depth, alignment and mapping, and mutation analyses. Sanger sequencing was used to confirm selected mutations. Sixty-two somatic short nucleotide variants (SNVs) and five deletions were identified inside coding regions, each causing a non-synonymous DNA sequence change. We selected seven SNVs and validated them by Sanger sequencing. In the metastatic ONB samples collected several months prior to WGS, all seven mutations were present. However, in the original surgical resection specimen (prior to evidence of metastatic disease), mutations in KDR, MYC, SIN3B, and NLRC4 genes were not present, suggesting that these were acquired with disease progression and/or as a result of post-treatment effects. Conclusions/Significance This work provides insight into the evolution of ONB cancer cells and provides a window into the more complex factors, including tumor clonality and multiple driver mutations.
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Abstract 5104: Identification of key tumorigenic pathways in pancreatic adenocarcinoma patients using massively parallel DNA and RNA sequencing. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-5104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: Pancreatic adenocarcinoma is among the most lethal forms of all malignancies. While significant research has implicated multiple genes in disease pathogenesis, identification of therapeutic leads has been difficult. The majority of currently available therapies provide only marginal benefit. To address this issue, our goal was to assess global somatic events across multiple pancreatic tumors by using next-generation sequencing technologies (NGS). Experimental Design: We performed whole genome sequencing (WGS) on paired tumor and normal samples from 3 pancreatic adenocarcinoma patients. Additionally, we performed whole transcriptome sequencing (WTS) on 2 of these patients’ tumors for which tumor RNA was available. Results: We generated on average 132 billion mappable bases across all patients using WGS, and identified 140 somatic coding events including point mutations, insertion/deletions, and chromosomal copy number variants. Data from WGS and WTS were integrated and analyzed to identify the most heavily affected pancreatic cancer pathways across all patients. The KRAS signaling pathway was identified as the most significant map. Unbiased global pathway analysis was also performed to identify processes that may be impacted. Consistent with the previous analysis, the most significant pathway from this analysis is also KRAS signaling. This integrated analysis specifically identifies heavily affected pathways in pancreatic cancer and pinpoints genes and processes that may be considered as targets for more effective therapies. Conclusions: While sequencing of additional patients is necessary to strengthen selection of key pathways, we demonstrate the utility of using NGS to understand the processes driving pancreatic adenocarcinoma so that standardized treatments for patients may be improved.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5104. doi:1538-7445.AM2012-5104
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Abstract 5072: Genome sequencing of metastatic colorectal carcinomas to identify potential targets for therapy in patients. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-5072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Colorectal carcinoma is one of the most common cancers in the western world, being the third most common cause of cancer-related morbidity and mortality. The outcome of patients with metastatic colorectal carcinoma (mCRC) following first line therapy, especially with a Kras mutation is poor with median survival of less than one year. The purpose of this study was to identify therapeutically actionable somatic events in mCRC patient samples, so as to obtain select targeted treatment strategies for individual patients. Fresh frozen needle biopsies of liver metastases were collected from three mCRC patients along with whole blood for the extraction of constitutional DNA. All patients had greater than 2 prior regimens and had known K-ras mutations. Whole genome sequencing was performed using Illumina paired-end chemistry on HiSeq2000 sequencing system, which yielded coverage of greater than 30X for both the normal and tumor samples. Somatic genomic alterations (point mutations and indels, copy number alterations, translocations and rearrangements) were analyzed using our custom pipeline for paired analysis. We found that all 3 tumor samples had KRAS mutations, while 2 samples had mutations in the APC gene and the PIK3CA gene. Other genes with therapeutic implications in single tumor samples were INPPL1, INPP4B and SMAD4. No EGFR amplifications were detected in our sample set. Pathway analysis revealed K-RAS regulation and apoptosis and survival pathways in these tumor samples. Analysis of paired-end data from these three tumors did not reveal the presence of translocations at the recently discovered TCF7L2 locus (Bass et al, Nature Genetics, 2011). The concomitant mutations in MAPK (KRAS) and PI3K (PIK3CA, INPPL1, INPP4B) pathways suggest that combination therapies might be required for effective treatment of these tumors. By harnessing the power of Next-Gen Sequencing, our study has revealed a series of therapeutically actionable events in mCRC that might provide insights into treating these difficult to treat advanced tumors.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5072. doi:1538-7445.AM2012-5072
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Abstract 5068: Identification of key tumorigenic pathways in never-smoker lung adenocarcinoma using massively parallel DNA and RNA sequencing and methylation profiling. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-5068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Considered independently, lung cancer in never-smokers would rank among the ten most common causes of cancer mortality. Driver pathways and potential therapeutics must be identified for this clinically relevant subpopulation. We hypothesize that novel mutations and pathways identified by whole genome sequencing (WGS), whole transcriptome sequencing (WTS), and methylation profiling drive tumorigenesis in adenocarcinomas (AC) of never-smoker (NS) patients, and represent potential therapeutic targets. We have completed WGS, WTS, and methylation profiling on two lung ACs from female, never-smokers, one early-stage and one stage IV, and one female smoker (S) patient with early-stage lung AC. Approximately 100 short nucleotide variants (SNV) were discerned from the early-stage and stage IV NS lung ACs. Of interest, these NS patients lacked alterations in common genes associated with lung cancer such as EGFR and KRAS. In comparison, the lung AC from a smoker contained 78 SNVs, including a well-characterized KRAS mutation. Mutations in MAGEC1, a tumor marker in melanoma, were observed in common between the early-stage NS tumor and the smoker lung AC. The early-stage NS tumor contained a mutation in PIK3C3 and CSNK1E, a casein kinase involved Wnt signaling. The stage IV NS tumor demonstrated mutations in tumor suppressor genes such as p53, LATS2, and ATM. With relatively few mutations discerned from NS lung ACs, WTS and methylation profiling were performed. WTS showed 1,083 genes differentially regulated in the early-stage NS and Ingenuity Pathway Analysis implicated G-protein coupled receptor signaling. 2,000 genes were differentially expressed in the stage IV NS lung AC with sonic hedgehog implicated as a significantly regulated pathway. Besides gene expression, methylation profiling revealed ∼3,100 differentially methylated genes in the early-stage NS lung AC compared to normal lung DNA, with 65% hypo-methylated, including genes involved in lung carcinogenesis such as RET and BCL2. In the stage IV NS lung AC, ∼35,000 genes were differentially methylated compared to normal lung DNA (10X the early-stage NS) with ∼62% hypo-methylated. Thus, while an early-stage smoker lung AC displayed a classic driver mutation in KRAS, lung ACs from never-smokers had relatively quiet genomes. Despite few mutations, thousands of genes were differentially regulated at the mRNA level or by methylation. We continue to validate the genes implicated in NS lung AC by mutation, differential expression, and differential methylation, as well as integrating the data across platforms to discern significantly regulated pathways. We believe that the genes and pathways implicated by WGS, WTS, and methylation profiling will lead to a better understanding of NS lung AC and identify possible therapeutic interventions.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5068. doi:1538-7445.AM2012-5068
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Abstract 3679: Paired tumor and normal whole genome and transcriptome sequencing of transitional cell carcinoma of the upper urinary tract. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-3679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Transitional cell carcinoma of the upper urinary tract (UUT) is a rare urothelial cancer, which most often affects males ages 50-70. Previous studies have shown some overlap with genetic alterations frequently observed in bladder cancer, however complete molecular characterization of UUT tumors is currently limited. A 20-year-old woman with treated acute lymphoblastic leukemia (ALL) in remission for ∼13 years, presented with present with numerous metastatic lesions involving bone, adrenal, retrocaval lymph node, and kidney. Biopsy confirmed a second primary carcinoma originating from the ureter or kidney. After two lines of systemic chemotherapy, the patient enrolled in a whole-genome (WGS) and whole transcriptome sequencing (WTS) pilot study. Methods: Tumor DNA and RNA was isolated from fresh-frozen tissue obtained by needle core biopsy of the right kidney tumor. Germline DNA was isolated from the patient's whole blood. Commercial benign ureter tissue was used for normal RNA comparison. Whole-genome paired-end library and transcriptome sequencing were done on Illumina's HiSeq 2000 platform. Burrows-Wheeler Transform algorithm was used in alignment to human reference genome (build 36). Several short nucleotide variants (SNVs) were selected for further validation with Sanger sequencing. Quantitative PCR with specific primers to either amplified or deleted genomic regions and ΔΔCt method were used to validate chromosomal copy number abnormalities. Results: WGS yielded 46X and 55X uniquely mappable reads for the tumor and normal samples, respectively. Seventy-one damaging somatic SNVs and a number of chromosomal aberrations were identified in regions of cancer relevant genes. Most notably, truncating mutations were found in p53 and KDM6A (oncogenic histone demethylase) genes as well as a damaging mutation in E2F8 transcription factor. KDM6A and E2F8 mutations were confirmed with bi-directional Sanger sequencing. A homozygous deletion encompassing the tumor suppressor p16 and a prominent focal 2MB high-level amplification at 7p11.2 that includes the EGFR oncogene were also detected. WTS produced ∼1006 reads for each sample. Expression analysis revealed loss-of-heterozygosity in p53 wild-type locus and a significant upregulation of EGFR. Additionally, a number of genes (MKI67, AURKA, TOP2A, BUB, FOXM, and PLK1) associated with cell cycle progression had >4-fold tumor overexpression. Genomic qPCR confirmed a 10-fold reduction in p16 while EGFR was amplified >40 times. Conclusion: Through WGS and WTS, a number of common oncogenic targets to be deregulated in this UUT, including p53 mutation, EGFR and MYC amplifications, and p16 deletion. These targets have previously been implicated in urothelial cancers, most notably in bladder. Given, negative KRAS mutation status, EGFR targeted therapy may be a reasonable treatment option for this patient.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3679. doi:1538-7445.AM2012-3679
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Abstract A43: Identification of key tumorigenic pathways in never-smoker lung adenocarcinoma patients using massively parallel DNA and RNA sequencing. Clin Cancer Res 2012. [DOI: 10.1158/1078-0432.12aacriaslc-a43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Lung cancer remains the leading cause of cancer deaths in the US and throughout the world. Never-smokers with lung cancer constitute an understudied subset of these patients, though recent estimates show that ∼10% of men and women with lung cancer in the US are never-smokers. Independently, lung cancer in never-smokers ranks among the ten most common causes of cancer mortality, and thus the causes, driver pathways, and potential therapeutics must be investigated for this clinically relevant subpopulation. We hypothesize that novel mutations and pathways identified by whole genome sequencing (WGS) and whole transcriptome sequencing (WTS) drive tumorigenesis in adenocarcinomas of never-smoker patients, and represent potential therapeutic targets. We have completed WGS and WTS on two lung adenocarcinomas from female, never-smokers, one early-stage and one advanced-stage (metastatic), and one female smoker patient with early-stage lung adenocarcinoma. Approximately 100 short nucleotide variants (SNV) causing non-synonymous DNA sequence changes were discerned from the early- and advanced-stage adenocarcinomas from never-smokers. Of interest, these never-smoker patients lacked alterations in common genes associated with lung cancer such as EGFR, KRAS, and EML/ALK translocations, making them ideal cases for the discovery of new mutations that may drive lung adenocarcinomas in never-smokers. In comparison, the adenocarcinoma from a smoker patient contained 78 SNVs, including a well-characterized KRAS mutation. Mutations in MAGEC1, a tumor marker in melanoma and multiple myeloma, were observed in common between the early-stage, never-smoker tumor and the smoker tumor. The mutations observed in the never-smoker cases included genes suspected to play a role in lung carcinogenesis. The early-stage, never-smoker patient contained a mutation in PIK3C3 and DOCK10, known to play a role in cancer cell migration, and CSNK1E, a casein kinase involved Wnt signaling and in beta catenin-induced cancer cell proliferation. The late-stage never-smoker patient demonstrated a p53 mutation, a mutation in the tumor suppressor LATS2, and a mutation in the DNA damage checkpoint gene, ATM. The mutations discovered in known tumor suppressor genes tended to be in the late-stage, never-smoke patient. Ingenuity Pathway Analysis implicated G-protein coupled receptor signaling for the early-stage never-smoker, Hif1α signaling for the smoker, and Sonic Hedgehog Signaling for the late-stage, never-smoker in both WGS and WTS. Currently, we are validating the identified mutations discovered by WGS using Sanger sequencing and surveying their frequency in ∼30 and ∼60 additional cases of lung adenocarcinoma from never-smokers and clinically matched smokers, respectively. Validation of these mutations and pathways will lead to a better understanding of tumorigenesis and tumor progression in never-smokers and identify nodes for therapeutic vulnerability.
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S3-5: Next Generation Sequencing Reveals Co-Activating Events in the MAPK and P13K/AKT Pathways in Metastatic Triple Negative Breast Cancers. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-s3-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
INTRODUCTION: The clinical application of next generation sequencing to comprehensively characterize groups of driving mutations in individual metastatic triple negative breast cancer (mTNBC) genomes has the potential to reveal therapeutically relevant pathway dependencies. Towards this end, we harvested tissue from 14 patients with mTNBC and are conducting deep whole genome and transcriptome sequencing for each case to identify mutations that can guide therapeutic targeting within available phase I/II clinical trials.
METHODS: Metastatic tumor tissue was harvested from 14 mTNBC patients, and 7 samples have undergone total genome and transcriptome sequencing with the others currently underway. We are utilizing the Life Technologies SOLiD® system to sequence germline and tumor DNA to sufficient depth to identify somatic genome alterations including point mutations, indels, and structural events including translocations. Furthermore, RNA-seq is being performed on these tumors, along with a series of age- and ethnicity-matched normal breast controls to perform deep differential expression analysis, isoform expression analysis, and fusion transcript detection. Our team of genome scientists and clinical oncologists are evaluating the sequencing findings and are prioritizing the investigational therapeutic options for each patient.
RESULTS: Our whole genome and transcriptome sequencing study has revealed numerous known and novel mutations in mTNBC. However, all patients’ cancers analyzed to date had alterations that would activate the MAPK pathway, but through various mechanisms in different patients. These include BRAF amplification and overexpression, NF1 homozygous deletion, and consistent IQGAP3 overexpression. Furthermore, all patients’ cancers also harbor mutations that would activate the PI3K/AKT pathway including PTEN homozygous deletion or down-regulation, consistent INPP4B down-regulation, FBXW7 homozygous deletion, and ERAS overexpression. Moreover, although we and others show ERBB4 down-regulation in breast tumors, we are the first to report unique somatic genomic events that significantly alter the ERBB4 locus leading to its loss in the majority (5/7) of our patients’ tumors. Importantly, we are beginning to use these insights to prioritize therapeutic targeting and have observed that one chemotherapy-refractory mTNBC patient, with a high-level BRAF amplification/overexpression along with down-regulation of PTEN and INPP4B, had a major response to combined mek plus akt inhibitors on a phase I study.
CONCLUSIONS: Comprehensive genomic and transcriptomic interrogation of mTNBCs has revealed events supporting co-activation of the MAPK and PI3K/AKT pathways in all the tumors albeit by different mutational mechanisms and supports potential effectiveness of combination therapy in the treatment of mTNBC. We plan to treat these patients with combined mek plus akt inhibitors on a new phase I study beginning in August 2011 to determine the effectiveness of co-inhibition of these pathways based on this frequent genomic context.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr S3-5.
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Abstract A183: Whole-genome sequencing to find potential targets for therapy in patients with refractory K-ras mutated metastatic colorectal cancer. Mol Cancer Ther 2011. [DOI: 10.1158/1535-7163.targ-11-a183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: The outcome of patients with metastatic colorectal carcinoma (mCRC) following first line therapy, especially with a K-ras mutation is poor with median survival of less than one year. The purpose of this study was to perform whole genome sequencing (WGS) to identify therapeutically actionable somatic events in mCRC patient samples, so as to select targeted treatment strategies for individual patients.
Methods: IRB approval was obtained and 3 patients have been enrolled. All had > 2 prior regimens and had known K-ras mutations (age 73, 45 and 50 years, all were male). Percutaneous needle biopsies of liver metastases were performed with whole blood collection for the extraction of constitutional DNA. WGS was performed using Illumina paired end chemistry on HiSeq2000 sequencing system, which yielded coverage of greater than 30X for both the normal and tumor samples. Somatic genomic alterations (point mutations and indels, copy number alterations, translocations and rearrangements) were analyzed using our custom pipeline for paired analysis.
Results: In all 3 samples sufficient DNA was extracted for sequencing. WGS and bioinformatics analysis took 3–4 weeks for completion. We found that all 3 tumor samples had KRAS mutations, while 2 samples had mutations in the APC gene and the PIK3CA gene. Other genes with therapeutic implications in single tumor samples were INPPL1, INPP4B and SMAD4. No EGFR amplifications were detected in our sample set. The concomitant mutations in MAPK (K-ras) and PI3K (PIK3CA, INPPL1, INPP4B) pathways suggest that combination therapies might be required for effective treatment of these tumors. In two instances, tumors were sent to a CLIA laboratory to allow for clinical validation of genomic events.
Conclusions: WGS is feasible from DNA obtained from percutaneous biopsies in a clinical setting. Our study has revealed a series of therapeutically actionable events in mCRC and prospective clinical trials are needed to validate this approach.
Funded by the Bisgrove-Scottsdale Healthcare and TGEN foundations.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A183.
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Abstract
Next-generation sequencing enables use of whole-genome sequence typing (WGST) as a viable and discriminatory tool for genotyping and molecular epidemiologic analysis. We used WGST to confirm the linkage of a cluster of Coccidioides immitis isolates from 3 patients who received organ transplants from a single donor who later had positive test results for coccidioidomycosis. Isolates from the 3 patients were nearly genetically identical (a total of 3 single-nucleotide polymorphisms identified among them), thereby demonstrating direct descent of the 3 isolates from an original isolate. We used WGST to demonstrate the genotypic relatedness of C. immitis isolates that were also epidemiologically linked. Thus, WGST offers unique benefits to public health for investigation of clusters considered to be linked to a single source.
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Abstract 4838: Longitudinal assessment of high risk t(4;14) multiple myeloma using next generation whole genome sequencing. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-4838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: In order to understand the genetic events associated with disease progression and the development of drug resistance in multiple myeloma, we studied four longitudinally collected samples from a single, high risk, t(4;14) multiple myeloma patient. Samples over a four-year period were available from diagnosis, at time of first progression on lenalidomide, second progression while on bortezomib, at time of relapsed refractory disease and with end stage plasma cell leukemia. To better understand these genetic events, we utilized DNA extracted from germline tissue and CD138 purified bone marrow tumor cells to conduct whole genome sequencing (WGS) utilizing the Life Technologies SOLiD™ platform. Results: We have sequenced over 100 billion bases per sample with whole genome fragment library sequencing providing an average of 30X aligned coverage at all four time points studied. Each sample was aligned to the reference genome (NCBI36/hg18) with BFAST and post-alignment removal of duplicates and recalibration performed with Picard and Genome Analysis Toolkit (GATK) respectively. We then called point mutations with SolSNP and compared the germline sample to each tumor sample utilizing the Paired Mutation Walker. To date, we have identified 224 nonsynonymous point mutations within 217 genes. We then utilized the Sorting Intolerant from Tolerant (SIFT) algorithm and identified 109 potentially damaging point mutations which include 108 novel mutations in coding exons. Of the 224 somatic mutations observed, only 20 of these mutations are common to all tumor time points. Interestingly, the diagnostic and bortezomib refractory (second progression) samples had 11 mutations in common while the lenalidomide refractory (first progression) sample shared only 4 mutations in common with the bortezomib refractory sample. This suggests the presence of multiple clones at diagnosis that, due to treatment selection pressure, may emerge or regress as the dominant clone. Preliminary pathway analysis reveals the presence of mutations in genes regulating NFKB and Akt, whose pathways are often dysregulated in cancer. Conclusions: Whole genome sequencing has revealed evidence of mutational differences in exons between tumor and germline DNA indicative of the presence of multiple clones at diagnosis and evolution of these clones over time. This data supports the use of multiple drug therapies that target multiple clones and challenges the long held assumption that a patient who becomes refractory to a particular treatment will always be refractory to that treatment. Additional evaluation in a larger population is needed to confirm these findings.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4838. doi:10.1158/1538-7445.AM2011-4838
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Abstract LB-267: Whole-genome and transcriptome interrogation of metastatic chemo-resistant triple negative breast cancer from African American patients. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-lb-267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Triple negative breast cancer (TNBC) is characterized by the absence of expression of estrogen receptor, progesterone receptor, and Her2-neu, and accounts for ∼15% of all breast cancer diagnoses. Adjuvant chremotherapy and surgery can be effective in many women, although relapse with chemoresistant tumors that are difficult to treat is common. Importantly, these tumors may disproportionately affect African American women. Here, we present initial integrated analysis of matched normal and tumor whole genome and tumor transcriptome sequencing data from three African American patients with metastatic chemo-resistant TNBC, to better understand the compendium of somatic events occurring in these tumors within this high-risk population.
Methods: Next Generation Sequencing was performed using the SOLiD version 4.0 system. Patient matched tumor and germline genomes are sequenced to 300 million mappable mate-pair reads (30X) and analyzed using custom paired analysis tools to uncover somatic alterations. Tumor transcriptomes are sequenced (RNA-seq) to 30 million uniquely aligned reads using Life Technologies Bioscope. For expression analysis, patient RNA-seq data are compared to data generated from ethnicity-matched population-based control hyperplastic breast tissue using EdgeR and DEGseq.
Results: On average, we detected >3 million germline variants in these three African American patients. Review of germline results also provides information on BRCA1/2 status. Somatic paired analysis has revealed point mutations, small indels, copy number alterations, and translocations, in known cancer genes, and has revealed potential novel genes as well. Among three patients sequenced thus far, we have uncovered both unique and common genomic and transcriptomic perturbations. In both patients, unique somatic genomic alterations are associated with upregulation of specific signaling pathways. RNA-seq-based expression analysis has revealed a profile dominated by perturbations in cell cycle mitotic checkpoint defects. Furthermore, integrated analysis has provided key insights into the transcriptional consequences of a number of genomic alterations including exon skipping events and the discovery of potential fusion transcripts. Importantly, DNA and RNA changes have been validated by independent methods and technologies.
Conclusions: Deep genome and transcriptome profiling of chemo-resistant TNBC has provided insights into events occurring in this difficult to treat cancer. These data are being leveraged to provide an opportunity for informed therapeutic options for intervention of this difficult to treat form of cancer.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-267. doi:10.1158/1538-7445.AM2011-LB-267
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