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• Head and Neck Organoid Biobank cohort, Issing et. al., 2025, RNA + WES data

  This dataset contains the raw fastq files of RNA and whole exome sequencing of the head and neck organoid biobank. For RNA sequencing, 41 organoid samples collected at different timepoints as well as before and after genetic modification are included. For WES, 25 samples of early organoid cultures or matching tumor tissues are included.

  Dataset EGAD50000001733

• Single-cell CITE-seq and TCR-seq data from AIM⁺ HIV-1-specific T cells

  Single-cell sequencing data from 2 HIV-1 post-intervention controllers and 2 non-controllers reported in Fisher, Garcia, Frattari, Naasz, et al. Longitudinal samples were collected before antiretroviral therapy inititation, during suppressive therapy, and after analytical treatment interruption.

  Dataset EGAD50000002247

• Sequencing data for oesophageal / related samples - Kazachenka et al (DNA)

  Data supporting: "The transcriptional landscape of endogenous retroelements delineates esophageal adenocarcinoma subtypes" WGS for 452 samples

  Dataset EGAD00001011095

• BulkTCR-sequencing data from different human intestinal CD8 T cell subsets.

  5000 cells of each subset of CD8 T cells (CD103-KLRG1+, CD103-KLRG1- and CD103+ from LP and CD103+ IELs) were sorted into tubes. A modified SMART protocol was used in first-strand cDNA synthesis, and TCRalpha / TCRbeta genes were amplified in two rounds of semi-nested PCR reaction, following the method described in detail in Risnes et al., 2018.

  Dataset EGAD00001005049

• RNA-seq transcriptome of bronchial brush samples from COPD and control

  Human subjects (COPD patients or apparently healthy controls) where investigated by bronchoscopy and a 5 mm brush was used to sample the subsegment airways of the right lung. The material obtained mainly consist of bronchial epithelial cells plus some contamination with leukocytes. For further details see Ziegler-Heitbrock et al, European Respiratory Journal, 40:823-829, 2012.

  Dataset EGAD00001002003

• Genotype data

  This dataset contains the imputed genotypes for 197 individuals. All individuals were genotyped with the Illumina HumanCoreExome-24 array. The individuals were phased with SHAPEIT and imputed to the 1000 Genomes Project Phase III using IMPUTE2. This dataset was generated as part of the following study: Panousis et al (2019). Combined genetic and transcriptome analysis of patients with SLE: Distinct, targetable signatures for susceptibility and severity

  Dataset EGAD00001005038

• Study of Women's Health Across the Nation (SWAN) Repository

  The Study of Womens Health Across the Nation (SWAN) is an active multi-site, multi-disciplinary, longitudinal study of women's health. Initially funded in 1994 by the National Institute on Aging (NIA), the National Institute of Nursing Research (NINR), and the Office of Research on Women's Health (ORWH), the overall goal of SWAN is to describe the natural history of the menopausal transition and the post menopause including biological, behavioral, and psychosocial characteristics. SWAN focuses on the impact of menopause on age-related chronic diseases, such as diabetes, cardiovascular disease, depression, bone loss and osteoporosis, as well as physical and cognitive functioning. SWAN has seven clinical study sites located in six states, two in California, and one each in Chicago, Boston, Detroit area, northern New Jersey and Pittsburgh. The SWAN cohort was recruited from these areas and consists of 3,302 African American, Caucasian, Chinese American, Hispanic and Japanese American women. SWAN participants were enrolled in 1996-1997 and have been seen annually or bi-annually for clinic visits, which include interviews, measurements, and the collection of blood and urine samples. SWAN participants have now been seen for the baseline and 15 follow-up visits.

  Study phs001470

• International Multi-Center ADHD Genetics Project

  The goal of the project is to complete a 600,000 tag SNP genome-wide association scan of 958 parent-child trios from the International Multisite ADHD Genetics (IMAGE) project, in order to assess the association of SNP markers with ADHD, analyze quantitative ADHD phenotypes, complete copy number analyses, assess parent of origin effects and season of birth effects, and test for epistasis among apparently uncorrelated genes. Acquiring DNA Samples All consent forms stipulate that the samples can only be used by researchers who have been approved by the National Institute of Mental Health (NIMH), National Institutes of Health. All consent forms, except those used at the Zürich site (N=141 subjects), explicitly indicate that the samples may be used by researchers from commercial enterprises seeking to benefit financially from the analysis of the samples. The Zürich consent does not prohibit such use. The Zürich consent form also included an "opt out" that allowed the subjects to indicate that they did not want their samples stored at the NIMH repository or used by researchers external to the project. No subjects enrolled in the project opted out. Consent groups and participant set ADHD (ADHD): 2758 (924 trios)

  Study phs000016

• Integrated Genomic Analysis of Periampullary Tumors at The Human Genome Sequencing Center, Baylor College of Medicine (HGSC-BCM)

  Adenocarcinomas arising in the complex environment of the ampulla of Vater constitute a histopathological heterogenous group, presumably originating from the different epithelial cellular constituents present at the site: pancreas, bile duct, and intestinal duodenum. These tumors have been described in many different ways: intra-ampullary, periampullary, intra-ampullary papillary-tubular neoplasm, ampullary-ductal, periampullary-duodenal, and ampullary-not otherwise specified. These varied classifications reflect the difficulty in classifying these tumors into specific groups. Only the tumors clearly localized in the bile duct or duodenum are identified as distal cholangiocarcinomas (CAC) or duodenal adenocarcinomas (DUOAC). The current classification is based on macroscopic features that may distinguish the epithelium of origin, microscopic features, clinicopathological criteria, histopathology and expression of differential markers. This classification is subjective and prone to inter-observer variability and significantly impacts on treatment selection and therapeutic development. In order to define subtypes of periampullary cancer with clinical relevance, we performed whole exome sequencing and copy number analysis of 160 cancers arising in the periampullary region, 62 of these clearly arising from either the bile duct (n = 44), or the duodenum (n = 18) and 98 periampullary cancers (AMPAC) where the epithelium of origin could not be clearly defined.

  Study phs000895

• Trisomy21: Risk Factors for Chromosome Nondisjunction (T21NDJ)

  The overall goal of the project is to identify genetic risk factors associated with chromosome 21 nondisjunction in the oocyte. The dataset derives from multi-site collection of live birth probands with Down syndrome due to standard trisomy 21 (T21) and their biological parents. The type of nondisjunction error (NDJ)(maternal or paternal) in all cases has been determined to be maternal in origin based on the chromosome 21 variants contributed from parent to proband. The Center of Inherited Disease with support from NICHD has conducted genome-wide genotyping using the Illuminia Human OmniExpress Plus Exome array on approximately 800 women who have been identified through their offspring with DS and have been characterized as having a maternal meiois I (MI) or meiosis II (MII) nondisjunction error. Genotypes from biological fathers of the offspring with DS can be used with the data on mothers to better define the type of nondisjunction error (MI or MII) and to refine the chromosome 21 recombination profile. We provide the type of nondisjunction error, knowing that this will be updated based on the new panel. We do not provide the recombination profile, as this can be best defined using the new comprehensive set of SNPs in the OmniExpress panel.

  Study phs000718

• Precision Medicine for Dilated Cardiomyopathy in European and African Ancestry

  The DCM Precision Medicine Study is a multi-site consortium-based cross-sectional study of families with an embedded open-label randomized controlled trial. The aims of the study are to test the hypothesis that dilated cardiomyopathy (DCM) has a substantial genetic basis and to evaluate the effectiveness of a family communication intervention in improving the uptake of preventive screening and surveillance in at-risk first-degree relatives. The Study goal was to recruit 1,300 individuals (600 non-Hispanic African ancestry, 600 non-Hispanic European ancestry, and 100 Hispanic; 50% female) meeting rigorous diagnostic criteria for idiopathic DCM (probands) and 2,600 of their relatives. The probands were inpatients or outpatients identified by heart failure and cardiac transplant cardiovascular physicians and clinical research personnel in heart failure/heart transplant programs at sites in the DCM Consortium. The DCM phenotype was selected for this study because of its prevalence and its prior inclusion in the development of virtually all pharmacotherapy for non-ischemic heart failure from reduced ejection fraction. Study procedures included obtaining family history, cardiac history, medical record review, surveys, and blood sample collection. Exome data from 1219 idiopathic DCM probands and 127 idiopathic DCM relatives are included in dbGaP.

  Study phs002641

• Joint-Specific TF Regulation in RA

  The mechanisms responsible for the distribution and severity of joint involvement in rheumatoid arthritis (RA) are not known. To explore whether site-specific fibroblast-like synoviocyte (FLS) biology might be associated with location-specific synovitis and explain the predilection for hand (wrist/metacarpal phalangeal joints) involvement in RA, we generated bulk, whole-genome transcriptomic and chromatin accessibility data from FLS. Samples were matched in age, sex, and were homogeneous in that all had significant joint damage with longstanding disease requiring surgical intervention. Analysis revealed joint-specific patterns of FLS phenotypes, with proliferative, migratory, proinflammatory, and matrix-degrading characteristics observed in resting FLS derived from the hand joints compared with hip or knee. TNF-stimulation amplified these differences, with greater enrichment of proinflammatory and proliferative genes in hand FLS compared with hip and knee FLS. Hand FLS also had the greatest expression of markers associated with an ‘activated' state relative to the ‘resting' state, with the greatest cytokine and MMP expression in TNF-stimulated hand FLS. Predicted differences in proliferation and migration were biologically validated with hand FLS exhibiting greater migration and cell growth than hip or knee FLS. Distinctive joint-specific FLS biology associated with a more aggressive inflammatory response might contribute to the distribution and severity of joint involvement in RA.

  Study phs003633

• NHLBI TOPMed - NHGRI CCDG: Pakistan Risk of Myocardial Infarction Study (PROMIS)

  The Pakistan Risk of Myocardial Infarction (PROMIS) study is a retrospective multicenter case-control cohort study of individuals with and without coronary heart disease from Pakistan. Multiple biological samples have been collected from the participants including DNA, plasma, serum, and whole blood. The goal of the study is to recruit 20,000 cases and 20,000 controls of Pakistani descent. Eligible cases were individuals aged 30-80 who presented to the emergency department of a participating recruitment center in Pakistan with clinical symptoms consistent with a myocardial infarction (MI), ECG changes consistent with MI, elevated troponin levels consistent with MI, and no prior history of cardiovascular disease. Controls were individuals of Pakistani descent who did not have a self-reported history of cardiovascular disease. This site hosts data generated via NHLBI's TOPMed program and NHGRI's Common Disease Genomics (CCDG) program. Both whole exome and whole genome data are presented here, namely 4,211 whole genomes from TOPMed, 3,859 whole genomes from NHLBI supplemental funds, 1,136 whole genomes and 16,855 whole exomes from CCDG. Please note that there is additional legacy whole exome data (7,298 subjects) also generated via NHGRI funds as part of the MIGen Exome Sequencing project that can be found in dbGaP at phs000917.

  Study phs001569

• Examination of Engineered LINE-1 Integration Events in HeLa Cells

  Long Interspsesed Element-1 (LINE1 or L1) encodes two proteins (ORF1p and ORF2p) required for its mobilization (i.e. retrotransposition) in the human genome. Human ORF2p, a 150kDa protein, has endonuclease (EN) and reverse transcriptase (RT) activities. L1 EN is classified as apurinic/apyrimidin-like endonuclease (APE) and is responsible for initiating target-site primer reverse transcription (TPRT) during the L1 retrotransposition cycle. During canonical TPRT, the L1 EN activity makes a single-strand endonucleolytic nick at a double-strand DNA target sequence in genomic DNA. The endonucleolytic nick is typically made at an L1 EN degnerate consensus cleavage sequence (5'-TTTT/A-3') exposing a free 3' hydroxy group that can be used as a primer by the ORF2p L1 RT activity to reverse transcribe the associated L1 RNA. Here, we characterized over 21,000 de novo engineered L1 retrotransposition events in HeLa cells to determine if L1 exhibits overt integration preferences in the human genome. Bru-seq of HeLa cells to determine actively transcribed regions of the genome was also performed. This Bru-seq data was used to determine if engineered L1 integration events preferentially integrate into transcribed regions of the genome, and to determine which strand during transcription may present itself as preferential during L1 retrotransposition.

  Study phs001669

• Rapid detection of expanded short tandem repeats in personal genomics using hybrid sequencing.

  Long expansions of short tandem repeats (STRs); i.e., DNA repeats of 2-6 nucleotides, are associated with some genetic diseases. Cost-efficient high throughput sequencing can quickly produce billions of short reads that would be useful for uncovering disease-associated STRs. However, enumerating STRs in short reads remains largely unexplored because of the difficulty in elucidating STRs much longer than 100 bp, the typical length of short reads. We propose ab initio procedures for sensing and locating long STRs promptly by utilizing the frequency distribution of all STRs and paired-end read information. We validated the reproducibility of this method using biological replicates and used it to locate an STR associated with a brain disease (SCA31). Subsequently, we sequenced this STR site in eleven SCA31 samples using SMRT? sequencing (Pacific Biosciences), determined 2.3-3.1 kb sequences at nucleotide resolution, and revealed that (TGGAA)- and (TAAAATAGAA)-repeat expansions determined the instability of the repeat expansions associated with SCA31. Our method could also identify common STRs, (AAAG)- and (AAAAG)-repeat expansions, which are remarkably expanded at four positions in an SCA31 sample. This is the first proposed method for rapidly finding disease-associated long STRs in personal genomes using hybrid sequencing of short and long reads.

  Study JGAS000002

• The Spatial Heterogeneity in Multiple Myeloma - from the Subclonal Architecture to the Immune Microenvironment (partly hipo_K08K)

  Multiple myeloma (MM) cells show pronounced heterogeneity not only within a given patient but also between spatially separated tumor loci in the bone marrow. Understanding this spatial heterogeneity is emerging as a critical challenge for the successful treatment of the disease. Yet, our understanding of spatial differences in the subclonal architecture, molecular signatures and interactions with the tumor microenvironment remains very limited. To address this shortcoming, we performed bulk and single-cell multi-region sequencing, including random bone marrow samples from the iliac crest and paired imaging-guided focal lesion specimens from 15 newly diagnosed MM patients. We found a median of 5 subclones per patient and unique subclones in focal lesions. Central features of spatial heterogeneity included a consistent down-regulation of the chemoattractant cytokines CXCL7 and CXCL12 in focal lesion tumor cells as well as a significant depletion of macrophages in the focal lesion microenvironment. In contrast, a site-specific expansion of T-cell clones was not detected in focal lesions. In conclusion, our results demonstrate the relevance of considering spatial heterogeneity with potential implications for immunotherapies and molecular studies analyzing the role of gene signatures and MM-microenvironment interactions in disease progression.

  Study EGAS00001006090

• Inhibiton of the GABPB1L-containing GABP tetramer is sufficient to reverse replicative immortality in TERT promoter mutant glioblastoma cells.

  Over 50 types of cancer acquire TERT promoter mutations. These single point mutations reactivate telomerase, allowing for indefinite maintenance of telomere length and enabling cellular immortalization. The transcription factor binding site created by the point mutations specifically recruit the ETS factor GABP, a multimeric transcription factor composed of the GABPα and GABPβ subunits. GABP can form two functionally independent transcription factor species – a dimer or a tetramer – depending on which of the structurally distinct GABPβ isoforms is incorporated into the complex. In this study, we show that genetic disruption of GABPβ1L, a tetramer forming isoform of GABPβ that is dispensable in normal development, results in TERT silencing in a TERT promoter mutation dependent manner. Failure to activate TERT expression by GABPβ1L culminates in telomere dysfunction, DNA damage, and mitotic cell death exclusively in TERT promoter mutant cells. Furthermore, exogenous expression of TERT is sufficient to prevent telomere degradation and loss of cell viability in GABPβ1L-reduced lines bearing the mutant TERT promoter. Orthotopic injection of tetramer-deficient mutant TERT promoter GBM cells rendered lower tumor burden and prolonged the overall survival of the tumor-bearing mice. These results highlight the potentially widespread role of GABPB1L in enabling replicative immortality of TERT promoter cancers.

  Study EGAS00001002582

• Mutational Patterns in Metastatic Cutaneous Squamous Cell Carcinoma

  Cutaneous squamous cell carcinoma (cSCC) from the head and neck typically metastasizes to the lymph nodes of the neck and parotid glands. When a primary is not identified, they are difficult to distinguish from metastases of mucosal origin and primary salivary gland SCC. Ultraviolet radiation causes a mutation pattern that predominantly features cytosine to thymine transitions at dipyrimidine sites and has been associated with cSCC. In this study, we used whole genome sequencing data from 15 cSCC metastases and show that a UV signature mutation is pervasive across the cohort and distinct from mucosal SCC. The mutational burden was exceptionally high and concentrated in some regions of the genome, especially insulator elements (mean 162 mutations / Mb). We therefore evaluated the likely impact of UV-induced mutations on the dipyrimidine rich binding site of the main human insulator protein, CCCTC-binding factor (CTCF), and the possible implications on CTCF function and the spatial organization of the genome. Our findings suggest that mutation signature analysis may be useful in determining the origin of metastases in the neck and the parotid gland. Furthermore, UV-induced DNA damage to insulator binding sites may play a role in the carcinogenesis and progression of cSCC.

  Study EGAS00001003370

• Quantitative analysis of a novel DNA hypermethylation panel for lung cancer diagnosis using bronchial specimens

  Non-diagnostic findings in Transbronchial Lung Biopsy (TBLB) and Endobronchial Ultrasound-guided Transbronchial Lung Biopsy (EBUS-TBLB) are not uncommon. A challenge is to improve lung cancer detection by TBLB/EBUS-TBLB. In order to improve the diagnostic yield of bronchoscopy, we used 850K methylation chip to identify methylation sites that distinguish malignant from benign lung nodules.We found that the combination of HOXA7, SHOX2,and SCT methylation analysis has the best diagnostic yield in 123 bronchial washing (sensitivity: 74·1%; AUC: 0·851) and 172 brushing samples (sensitivity: 86·1%; AUC: 0·915). We developed a kit comprising these three genes and validated the kit in 329 unique bronchial washing samples, 397 unique brushing samples, and 179 unique patients with both washing and brushing samples. The diagnostic accuracy of the panel alone in lung cancer diagnosis was 86·9%, 91·2% and 95% in bronchial washing, brushing, and washing+brushing samples, respectively. The panel's sensitivity in combination with cytology, rapid on-site evaluation (ROSE), and histology in lung cancer diagnosis was 90·8% and 95.8% in bronchial washing and brushing samples, respectively, and 100% in washing+brushing samples. Quantitative analysis of the three-gene panel improves lung cancer diagnosis by bronchoscopy.

  Study EGAS00001007089

• Platinum Genomes

  Improvement of variant calling in next-generation sequence data requires a comprehensive, genome-wide catalogue of high-confidence variants called in a set of genomes for use as a benchmark. We generated deep, whole-genome sequence data of seventeen individuals in a three-generation pedigree and called variants in each genome using a range of currently available algorithms. We used haplotype transmission information to create a phased "platinum" variant catalogue of 4.7 million single nucleotide variants (SNVs) plus 0.7 million small (1-50bp) insertions and deletions (indels) that are consistent with the pattern of inheritance in the parents and eleven children of this pedigree. Platinum genotypes are highly concordant with the current catalogue of the National Institute of Standards and Technology for both SNVs (>99.99%) and indels (99.92%), and add a validated truth catalogue that has 26% more SNVs and 45% more indels. Analysis of 334,652 SNVs that were consistent between informatics pipelines yet inconsistent with haplotype transmission ("non-platinum") revealed that the majority of these variants are de novo and cell-line mutations or reside within previously unidentified duplications and deletions. The reference materials from this study are a resource for objective assessment of the accuracy of variant calls throughout genomes.

  Study phs001224

• A Chromatin Accessibility Atlas of the Developing Human Telencephalon

  Gene expression differs between cell types and regions within complex tissues such as the developing brain. To discover regulatory elements underlying this specificity, we generated genome-wide maps of chromatin accessibility in nine anatomically-defined regions of the developing human telencephalon. Additionally, we defined the histone modification landscape of the prefrontal cortex and generated chromatin accessibility maps of its upper and deep layers. We predicted a subset of open chromatin regions (18%) that are most likely to be active enhancers, many of which are dynamic with 26% differing between early and late mid-gestation and 28% present in only one brain region. These predicted regulatory elements (pREs) are enriched proximal to genes with expression differences across developmental stages, regions, and cortical laminae; they harbor distinct sequence motifs that suggest potential upstream regulators. We leveraged this atlas to predict and validate novel regulatory elements of genes that control cortex laminar identity and genes associated with autism spectrum disorder (ASD). These include enhancers proximal to FEZF2 and BCL11A that were validated in mouse, and an enhancer of ASD gene SLC6A1 containing two functional de novo mutations in individuals with ASD whose enhancer function we validated via CRISPRa. We also include data for transcription factor binding in mid-fetal cortex tissues, using CUT&RUN methods.

  Study phs002033

• Single_Cell_Sequencing_of_Sperm__scSperm_

  The aim of this project is to genotype and sequence single spermatozoa from two men, one in his twenties and the other in his seventies. The resulting data is used to quantify the mutations that have arisen in the gametes of both individuals in order to better understand the effect of aging on mutation rates and modes.Project Outline. In order to quantify mutations, semen from two individuals are sequenced. 48 single sperm cells are isolated from each individual, and their DNA is extracted. The resulting genomes are amplified using PicoPlex, GenomiPhi MDA, Repli-G MDA, and MALBAC. QC step is applied to check the quality of WGA DNA using standard Sequenom plex (26 SNPs). A subset of 32 amplification products which pass the intiall QC, are genotyped using Affymetrix SNP6 chips. 12 of the genotyped amplification products are also sequenced. In addition, one multi-cell sample per individual is sequenced as a reference and for validation purposes.Altogether, 12 single cell sperm genomes and two multi-cell genomes are sequenced, coming to a total of 14 genomes. Of the single cell sperm genomes, 2 are sequenced to 50x coverage, and the other 10 to 25x coverage. Both multi-cell genomes are sequenced to 25x coverage.

  Study EGAS00001000935

• Pancreatic, Small-intestinal and Pulmonary Neuroendocrine Tumors

  Purpose: The primary origin of neuroendocrine tumor metastases can be difficult to determine by histopathology alone, but is critical for therapeutic decision making. DNA methylation-based profiling is now routinely used in the diagnostic workup of brain tumors. This has been enabled by the availability of cost-efficient array-based platforms. We have extended these efforts to augment histopathological diagnosis in neuroendocrine tumors. Experimental Design and Results: We compiled data of 69 small-intestinal, pulmonary, and pancreatic neuroendocrine tumors. These data were used to build a ridge regression calibrated random forest classification algorithm (NEN-ID) that predicts the origin of tumor samples with high accuracy (> 95%). The model was validated during 3x3 nested cross validation and tested in a local (n=26) and external (n=172) cohort. In addition, we show that our diagnostic approach is robust across a range of possible confounding experimental parameters such as tumor purity and array quality. A software infrastructure and online user interface was built to make the model available to the scientific community. Conclusions: This DNA methylation-based prediction model can be used in the workup for patients with neuroendocrine tumors of unknown primary. To facilitate validation and clinical implementation, we provide a user-friendly, publicly available web-based version of NEN-ID.

  Study EGAS00001004878

• Spatiotemporal Genomic Profiling of Intestinal Metaplasia Reveals Clonal Dynamics of Gastric Cancer Progression

  Intestinal metaplasia (IM) is a pre-malignant condition of the gastric mucosa associated with increased gastric cancer (GC) risk. We analyzed 1256 gastric samples (1152 IMs) from 692 subjects from a 10-year prospective study. We identified 26 IM driver genes in diverse pathways including chromatin regulation (ARID1A) and intestinal homeostasis (SOX9), largely occurring as subclonal events. Analysis of clonal dynamics between and within subjects, and also longitudinally across time, revealed that IM clones are likely transient but increase in size upon progression to dysplasia, with eventual transmission of genetic events to paired GCs. Single-cell and spatial profiling highlighted changes in tissue ecology and lineage heterogeneity in IM, including an intestinal stem-cell dominant cellular compartment linked to early malignancy. Expanded transcriptome profiling revealed expression-based molecular subtypes of IM, including a body-resident “pseudoantralized” subtype associated with incomplete histology, antral/intestinal cell types, ARID1A mutations, inflammation, and microbial communities normally associated with the healthy oral tract. We demonstrate that combined clinical-genomic models outperform clinical-only models in predicting IMs likely to progress. Our results raise opportunities for GC precision prevention and interception by highlighting strategies for accurately identifying IM patients at high GC risk and a role for microbial dysbiosis in IM progression.

  Study EGAS00001007067

• Liquid Biopsy Versus Tissue Biopsy to Assess Acquired Resistance and Tumor Heterogeneity in Gastrointestinal Cancers

  Tumor heterogeneity can drive the evolution of multiple tumor subclones harboring unique molecular resistance alterations in different metastatic lesions in an individual patient, under the selective pressure of therapy1-3. Studies have suggested that liquid biopsy may better capture the heterogeneity of acquired resistance, but systematic, direct comparisons of post-progression liquid vs. standard single-lesion tumor biopsies are lacking. In a prospective cohort of 44 patients with molecularly-defined gastrointestinal cancers and acquired resistance to targeted therapy, direct comparison of post-progression liquid vs. tumor biopsy revealed that liquid biopsy more frequently identified clinically-relevant resistance alterations and multiple resistance mechanisms, detecting resistance alterations not detected in matched tumor biopsy in 78% of cases. Whole-exome sequencing of serial cell-free DNA, tumor biopsies and rapid autopsy specimens elucidated geographic and evolutionary characteristics of heterogeneity. Our data suggest that acquired resistance is frequently characterized by profound tumor heterogeneity and highlight the potential clinical utility of liquid biopsy. Burrell, R. A. & Swanton, C. Tumour heterogeneity and the evolution of polyclonal drug resistance. Molecular oncology 8, 1095-1111, doi:10.1016/j.molonc.2014.06.005 (2014). Misale, S. et al. Emergence of KRAS mutations and acquired resistance to anti-EGFR therapy in colorectal cancer. Nature 486, 532-536, doi:10.1038/nature11156 (2012). Ahronian, L. G. et al. Clinical Acquired Resistance to RAF Inhibitor Combinations in BRAF-Mutant Colorectal Cancer through MAPK Pathway Alterations. Cancer Disco 5, 358-367, doi:10.1158/2159-8290.Cd-14-1518 (2015).

  Study phs001853