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• Genetics of Prostate Cancer in Africa

  African Americans (AA) suffer from the highest rates of Prostate Cancer (CaP) in the world, but while men of African descent around the world suffer disproportionately from CaP compared to men of other races or ethnicities, our understanding of the reasons for these disparities remains incomplete. To date, few exposure, lifestyle, or environmental influences have been identified in CaP etiology. In contrast, CaP is among the most heritable of common cancers, and over 290 susceptibility loci have been identified. However, many of these loci have not been replicated in AA, in part because of limited African descent sample sizes, incomplete capture of African alleles, and a limited understanding of African genomic architecture. To better understand the etiology of CaP in African descent men, we established a large, multicenter consortium known as “Men of African Descent and Carcinoma of the Prostate” (MADCaP). Using resources of this consortium, we have undertaken a multicenter study of CaP in Sub-Saharan Africa, enrolling CaP cases from 7 institutions in 4 countries in Africa (Nigeria, Senegal, Ghana, and South Africa) and age matched controls from the same institutions. We designed a novel genotyping array, in partnership with Thermo Fisher Scientific, leveraging its Applied BiosystemTM AxiomTM Genotyping solution, to provide good coverage of African genomic variation, as well as incorporating cancer loci, with the goal of being able to fine-map existing prostate cancer loci, as well as mapping novel loci. The data available encompasses genotyping our Africa cohort on this array.

  Study phs002718

• Clonally selected lines after CRISPR/Cas editing are not isogenic

  The CRISPR-Cas9 system has enabled researchers to precisely modify/edit the sequence of a genome. A typical editing experiment consists of two steps: (i) editing cultured cells and (ii) selection of clones, which are presumed to be isogenic, with and without the intended edit. The application of the CRISPR-Cas9 system may result in off-target edits, while cloning would reveal culture-acquired mutations. We analyzed the extent of the former and of the latter by whole genome sequencing (WGS) involving separate genomic loci in three experiments conducted by three independent laboratories. In all experiments we hardly found any off-target edits, while we detected hundreds to thousands of single nucleotide mutations unique to each clone after relatively short culture of 10-20 passages. Notably, clones also differed in copy number alterations that were several kb to several mb in size, representing the largest source of genomic divergence among clones. This study in dbGaP includes data from experiments carried out by investigators at the Oklahoma Medical Research Foundation and Baylor College of Medicine (OMRF/BCM) involving an iPSC line derived from fibroblasts of a female patient (line c7) carrying a constitutional heterozygous variant (chr1:1,464,679 C>T; GRCh37) in exon 15 of the ATPase family, AAA domain containing 3A (ATAD3A) gene. The parental line was edited by introducing a double stranded break at the variant allele to correct the variant by homology directed repair. Two unedited control clones (clone7 and clone8) and one edited clone (SC20) were selected for WGS.

  Study phs003110

• Intra-tumor heterogeneity and clonal evolution of papillary renal cell carcinoma

  Limited knowledge of intratumor heterogeneity (ITH), and clonal evolution of papillary renal cell carcinoma (pRCC) and rare kidney tumor subtypes hinders understanding of tumorigenesis and therapeutic efficacy. We conducted an integrative genomic and epigenomic ITH analysis and studied clonal evolutionary history of pRCC and rare kidney tumor subtypes. We dissected multiple consecutive samples from the center of the tumor towards the tumor's periphery, a normal sample ~5 cm distant from the tumor, and, where feasible, metastatic regions in the adrenal gland. Specifically, we performed 60X multi-region whole-genome sequencing (mWGS), both genome-wide methylation and SNP array profiling, and deep targeted sequencing (average 500X coverage) of 254 cancer driver genes (PMID:24390350). The study population comprises 39 patients with kidney cancers, including 23 with papillary type 1 (pRCC1), 12 with papillary type 2 (pRCC2), one of which also had areas of clear cell, and one each with collecting duct tumor (cdRCC), renal fibrosarcoma rSRC, mixed pRCC1/pRCC2, and an unclassified renal cancer with mixed features of pRCC2 and cdRCC. Based on DNA sample availability, we conducted whole genome sequencing (WGS) on 124 samples from 29 subjects, deep targeted sequencing on 139 samples from 38 subjects, SNP array genotyping on 101 samples from 38 subjects, and genome-wide methylation profiling on 139 samples from 28 subjects. All assays were performed on tumor, metastasis and normal tissue samples, with the exception of the SNP array genotyping, which was conducted only on tumor samples.

  Study phs001573

• High-Resolution Clonal Mapping of Multi-Organ Metastasis, and Resistance to Neoadjuvant Chemotherapy, in Triple Negative Breast Cancer

  Clonal dynamics during metastasis were studied in two patient-derived xenograft (PDX) models established from treatment-naive primary breast tumors from TNBC patients diagnosed with concurrent metastatic disease. Genomic sequencing and barcode-mediated clonal tracking revealed robust alterations in clonal architecture between primary tumors and metastases. Polyclonal seeding and maintenance of low-abundance subclones was observed in each metastatic lesion examined. Lung, liver, and brain metastases were enriched for an identical population of subclones. Clones dominating multi-organ metastases shared a genomic lineage. Thus, properties of rare mammary tumor subclones enabled the seeding and colonization of metastases in multiple secondary organ sites. In this study, patient-derived xenograft (PDX) models of treatment-naive TNBC and serial biopsies from TNBC patients undergoing NACT were used to elucidate mechanisms of chemoresistance in the neoadjuvant setting. Barcode-mediated clonal tracking and genomic sequencing of PDX tumors revealed that residual tumors remaining after chemotherapy maintained the subclonal architecture of untreated tumors yet their transcriptomes, proteomes, and histologic features were distinct from those of untreated tumors. Once treatment was halted, residual tumors gave rise to chemotherapy-sensitive tumors with similar transcriptomes, proteomes, and histological features to those of untreated tumors. Taken together, these results demonstrated that tumors can adopt a reversible drug-tolerant state that does not involve clonal selection as a chemotherapy resistance mechanism. Serial biopsies obtained from patients with TNBC undergoing NACT revealed similar histologic changes as well as maintenance of stable subclonal architecture, demonstrating that PDXs capture molecular features characteristic of human TNBC chemoresistance.

  Study phs001742

• Follow-up of Ovarian Cancer Genetic Association and Interaction Studies (FOCI)

  (Excerpted/paraphrased from original grant application): FOCI seeks to expand our understanding of epithelial ovarian cancer through a coordinated and comprehensive approach. Project 1 will focus on discovery, expansion, and replication. By pooling GWAS, we expect to identify new associations and achieve independent replication, explore whether there are risk variants specific for histologic subtypes, and evaluate structural polymorphisms - copy number variants - as risk factors. Finally, Project 1 will leverage the GWAS data to correlate DNA variants with a new endpoint - survival. Project 2 will focus on biological studies designed to help inform interpretation of findings from Project 1. This will include efforts to identify the functional consequences of variants and improve understanding of biological mechanisms. Project 3 will include epidemiologic studies of gene by gene interaction, gene by environment interaction, and development of risk prediction models. The collective effort builds upon the strengths and history of collaboration inherent in the Ovarian Cancer Association Consortium (OCAC), a multidisciplinary group comprised of epidemiologists, genetic epidemiologists, statistical geneticists, molecular and cell biologists and clinicians that was formed in 2005. The FOCI Cohort is utilized in the following dbGaP sub-studies. To view genotypes, other molecular data, and derived variables collected in these sub-studies, please click on the following sub-studies below or in the "Sub-studies" box located on the right hand side of this top-level study page phs001133 FOCI Cohort. phs001131 Affymetrix Exome Chip phs001132 GWAS Meta Analysis phs001142 Mayo Omni Express phs001150 Mayo 2 5M

  Study phs001133

• Rare Diseases Clinical Research Network (RDCRN) Vasculitis Clinical Research Consortium (VCRC) Longitudinal Protocol for Polyarteritis Nodosa

  The development and validation of accurate biological markers and predictors of disease activity and outcome in Polyarteritis Nodosa (PAN), a form a idiopathic vasculitis, would have a major positive impact on the clinical care of patients with this rare disease, be an important advance in the design of clinical trials and feasibility of new drug development, and provide important insight into the pathogenesis of this condition. Current measures of disease activity, including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), while helpful in selected settings, are mostly considered highly flawed and markers whose poor correlation with disease flares makes them inadequate to help guide therapy. Similarly, ESR and CRP are clearly unhelpful as diagnostic tests for vasculitis. The current state of clinical investigation for vasculitis relies heavily upon determination of disease status solely by clinical presentation and investigator opinion. Thus, discovery and validation of more precise markers that quantifiably measure activity, predict disease course, and correlate with an important biological process, would be of great importance. Knowledge to be gained from this study could potentially be highly important. Discovery of effective biomarkers of vasculitis and assessment of long term disease course and complications by the collection of clinical and diagnostic imaging studies proposed could lead to better care and less toxic treatment regimens. Furthermore, insight into the pathophysiology of vasculitis could be gained and this might lead to better treatments and improved outcomes in terms of reduction of vascular and treatment related complications. Ideally, excellent biomarkers reflect a sophisticated understanding of the pathophysiology of a disease.

  Study phs000590

• Genetic Modifiers of Syndromic Orofacial Clefts

  Reduced penetrance and variable expressivity are common, but poorly understood, features of most monogenic diseases. Genetic modifiers are possible factors to contribute to this phenotypic variability and blur the traditional distinction between monogenic and complex disease. This study focuses on the most common orofacial cleft syndrome (Van der Woude syndrome, VWS) and nonsyndromic orofacial clefts (OFCs), which intersect both in phenotype and in genetic etiology, as a model to understand reduced penetrance and variable expressivity. VWS occurs in 1 in 35,000 individuals and accounts for 2% of all OFCs. The features of VWS include an OFC and/or lower lip pits, but 15% of VWS patients present with an isolated OFC, making them indistinguishable from nonsyndromic OFC patients. Mutations in the genes IRF6 or GRHL3 cause VWS, but approximately 20% of VWS patients currently lack a molecular diagnosis. Furthermore, there are few genotype-phenotype correlations for known mutations and patient phenotypes. By contrast, GWAS of nonsyndromic OFCs have identified a number of risk factors, some of which we have shown increase risk for specific types of OFCs or act as modifiers of OFC subtypes. Whole genome sequencing will be used to identify the remaining genetic mutations for VWS, determine the relationship between those genes/regions with nonsyndromic OFCs, and identify rare and common modifiers of VWS and OFC phenotypes. These analyses will provide further insight into the genetic architecture of VWS and OFCs and will serve as a model for exploring links between other Mendelian disorders that share phenotypes with complex traits.

  Study phs002221

• Basal-to-Inflammatory Transition Contributes to Basal Cell Carcinoma Therapy Resistance via Crosstalk with a Pro-Inflammatory Stromal Niche

  Overcoming tumor evolution and inducible resistance states remain the main challenge to creating successful anti-tumor therapies. The body's cancer-associated inflammatory response is a double-edged sword having ill-defined pro- and anti-tumor properties. Our group previously identified a basal cell carcinoma (BCC) tumor-intrinsic resistance pathway called basal to squamous cell carcinoma transition (BST). However, tumor resistance driven through the complex dynamics of tumor interactions with the inflammatory response remains poorly studied. Here, employing a multipronged approach combining human tumor single-cell transcriptomics, single-cell chromatin accessibility (scATAC-Seq) study, CODEX multiplexed imaging, spatial transcriptomic along with functional validation, we have identified a surprising inflammation-associated SMOi therapy enriched tumor epithelial cell state we term basal-to-inflammatory transition (BIT). Marked by CHI3L1, TAGLN, ITGAV, and VCAM1, BIT arises in spatially distinct neighborhoods from BST in a subset of naive BCCs. While BST tumor epithelium occurs within the central cores of tumor nodules, BIT tumor epithelium arises in a specialized inflammatory environment defined by a tumor associated TREM1 myeloid signature. IL1 and OSM secreted by TREM1 myeloid cells activate the inflammatory NF-kB family of transcription factors within the BIT tumor epithelium. Strikingly, IL1 and OSM ligands are sufficient not only in inducing the BIT tumor state in vitro and in vivo in a synergistic fashion but also in lowering the sensitivity of human BCC explant tumors to SMOi treatment. This work provides critical insights into the BIT-resistant state as a novel targetable tumor state driven by a specialized inflammatory microenvironment.

  Study phs003437

• Tumor Evolution Analysis Uncovered Immune-Escape Related Mutations in Relapsed Diffuse Large B-Cell Lymphoma

  More than 60% of patients with primary diffuse large B-cell lymphoma (DLBCL) achieve durable remissions upon the chemoimmunotherapy with R-CHOP. However, the outcome of the relapse patients is extremely poor. To characterize the molecular features that underlie treatment resistance, we performed whole-exome sequencing (n=44) and deep targeted sequencing (n=27) of 44 diagnosis-relapse DLBCL pairs. We found that the overall landscape of genetic alterations was concordant between diagnosis and relapse DLBCL. By a deep comparison of the longitudinal sequencings, we identified relapse-enriched mutations that involved in evasion of immune surveillance (CD58, TNFRSF14, PKD1, FAS), resistance to DNA damaging agents (ATM, TP53), and critical tumor suppressor gene (ZFHX3). Knockdown of ATM and ZFHX3 resulted in increased drug resistance in both germinal center B cell like (GCB) and activated B cell like (ABC) DLBCL cell lines in vitro, while the knockdown of TNFRSF14 and FAS conferred resistance specifically in GCB cell lines. Furthermore, we summarized two evolutionary patterns of DLBCL relapse as the “durable retention” model with stable clone structure, and the “selective sweep” model which exhibited significant clonal switch. Of note, genetic alterations leading to attenuated immune responses usually presented as trunk mutations in the “durable retention” model (7/12) while were newly acquired or expanded upon relapse in the “selective sweep” model (9/16). Overall, our study demonstrated that relapse DLBCL derives from distinct clonal evolutionary patterns, and highlighted immune escape as an important contributor of tumor relapse.

  Study EGAS50000000032

• Digitalis Investigation Group (DIG-BioLINCC)

  Data Access NOTE: Please refer to the “Authorized Access” section below for information about how access to the data from this accession differs from many other dbGaP accessions. Objectives To determine the effect of increasing age on mortality, hospitalizations, and digoxin side effects in patients with heart failure (HF), and to determine whether the effect of digoxin on clinical outcomes varies as a function of age. Background The incidence and prevalence of HF increase with advancing age, but there are limited data on the clinical course and response to specific interventions in elderly patients with HF. Participants A total of 302 centers in the United States and Canada enrolled 7,788 patients between February 1991 and September 1993. Design The Digitalis Investigation Group (DIG) study was a prospective, randomized clinical trial involving 7,788 patients with HF randomized to digoxin or placebo and followed for an average of 37 months. Interactions between age and the following clinical outcomes were examined: total mortality, all-cause hospitalizations, HF hospitalizations, the composite of HF death or HF hospitalizations, hospitalization for suspected digoxin toxicity and withdrawal from therapy because of side effects. Conclusions Increasing age is associated with progressively worse clinical outcomes in patients with HF. However, the beneficial effects of digoxin in reducing all-cause admissions, HF admissions, and HF death or hospitalization are independent of age. Thus, digoxin remains a useful agent to the adjunctive treatment of HF due to impaired left ventricular systolic function in patients of all ages.

  Study phs003872