The aim of this study was to compare copy-number-variation (CNV) detection methods for targeted NGS panel data in a clinical diagnostic setting. We present targeted NGS panel data from 170 samples that were processed using the TruSight(TM) Cancer (TSC) panel (Illumina, San Diego, CA, USA), which targets 94 genes and 284 SNPs associated with a predisposition towards cancer. The samples are enriched for CNVs in the genes of interest. All CNVs have previously been assessed with MLPA and can therefore be considered as confirmed.
The goal of the study was to compare the transcriptome of patient-derived serum-free GBM cell lines to that of parental GBM tumors. For each patient, three samples were analyzed: GBM tumor, cell line growing at 5% oxygen, and cell line growing at 20% oxygen. Analysis demonstrated the enrichement in cell cycle and DNA repair gene expression in cell lines when compared to parental tumor sample. Moreover, cells cultured at 5% oxygen maintained hypoxia, carbon metabolism and tumor progression transcriptional pattern characteristic for GBM.
DNA lesions encountered by replicative polymerases threaten genome stability and cell cycle progression. Here we report the identification of mutations in TRAIP, encoding an E3 RING ubiquitin ligase, in patients with microcephalic primordial dwarfism/Seckel syndrome. We establish that TRAIP relocalizes to sites of DNA damage where it is required for optimal phosphorylation of H2AX and RPA2 during S-phase in response to UV irradiation, as well as fork progression through UV-induced DNA lesions. TRAIP is necessary for efficient cell cycle progression and mutations in TRAIP therefore limit cellular proliferation, providing a potential mechanism for microcephaly and dwarfism phenotypes. Human genetics thus identifies TRAIP as a novel component of the DNA damage response to replication-blocking DNA lesions.
Transcription factor MECOM, located at 3q26, is essential for hematopoietic stem cells (HSCs) in healthy individuals. Enhancer translocations, due to 3q26 rearrangements, drive out-of-context MECOM expression in an aggressive subtype of leukemia (AML). Aberrantly expressed MECOM is essential for the survival and immature phenotype of these leukemia cells. Direct depletion of MECOM using an endogenous auxin-inducible degron rapidly upregulates expression of myeloid differentiation factor CEBPA. MECOM depletion is also accompanied by a severe loss of CD34 expression and gain of mature myeloid cell surface marker CD15. MECOM exerts its inhibitory effect on differentiation by binding to the +42kb CEBPA enhancer, which is essential for neutrophil development. This is partially dependent on the interaction between MECOM and its essential co-repressor CTBP2, a potential target in this type of AML. We demonstrate that CEBPA overexpression can bypass the MECOM-mediated block of differentiation. In addition, AML patients with MECOM overexpression through enhancer hijacking show significantly reduced CEBPA. Our study provides insight into the mechanism by which MECOM maintains the stem cell state in AML. Furthermore, CEBPA levels are an important read-out for successful targeting of MECOM in 3q26-rearranged AML.
Age is the primary risk factor for Parkinson's disease (PD), but how aging to change the expression and regulatory landscape of the brain remains unclear. Here, we present a single-nuclei multiomic study profiling shared gene expression and chromatin accessibility of young, aged and PD post-mortem midbrain samples. Combined multiomic analysis of midbrain nuclei along a pseudo-pathogenesis trajectory reveals that all glial cell types are affected by age, but microglia and oligodendrocytes are further altered in PD. We present evidence for a novel disease-associated oligodendrocyte subtype and identify genes lost over the aging and disease process, including CARNS1, that may predispose healthy cells to develop a disease-associated phenotype. Peak-gene association analysis from paired data identifies 89 PD-associated SNP loci, including five in MAPT, that only correlate with gene expression in disease-associated oligodendrocytes. Our study suggests a previously undescribed role for oligodendrocytes in aging and PD pathogenesis.
We studied the genomic signatures of progression in breast ductal carcinoma in situ (DCIS) as it progresses towards triple negative invasive breast cancer (TNBC). Single cell RNA sequencing (scRNAseq) was performed on the C3Tag genetically engineered mouse model that forms human breast-like DCIS and TNBC. Bulk RNA sequencing was performed on RNA harvested from archival formalin-fixed, paraffin embedded (FFPE) pairs comprising of estrogen receptor (ER) positive (ER+) and negative (ER-) subsets of DCIS.
Genetic changes acquired during culture pose a potential risk for the successful application of stem cells. To assess the risk of in vitro expansion on mutation accumulation we have performed whole genome sequencing of clonally expanded human induced pluripotent stem cells (iPS cells) and adult stem cells (ASCs) to identify all mutations that accumulated over a fixed culture period. We find that ASCs acquire more single nucleotide variants (SNVs) and indels per population doubling than the iPS cells. When compared with ASCs, iPS cells are more vulnerable to mutations in genes and promoters. Mutational analysis revealed a clear in vitro induced mutational signature that is irrespective of stem cell type. This in vitro signature is characterized by C to G transversions that are probably caused by oxidative stress. Additionally, we observed stem cell specific mutational signatures and differences in transcriptional strand bias, indicating differential activity of DNA repair mechanisms between stem cell types in culture. In conclusion, in vitro culture induces mutation accumulation in iPS cells and ASCs. Culture under low-oxygen tension may help to reduce the number of culture-induced mutations.
Oncogenic mutations confer aberrant replicative capacity to cells with little or no replicative capacity, generating cancer stem cells that perpetuate the tumor through extensive self-replication and differentiation blockade. However, whether oncogenes disrupt the cellular identity ofcancer stem cell by altering the developmental potential is unknown. Fate conversion has been demonstrated by ectopic expression of master transcriptional regulators, such as PU.1 and C/EBP alpha that confers myeloid cell fate to other cell types, and PRDM16 that confers brown adipose fate to white adipocytes or myoblasts. Here we show that a transcriptional regulator overexpressed in human myeloid malignancies, PRDM16s, causes oncogenic fate conversion, by transforming cells fated to form platelets and erythrocytes into myeloid leukemia-initiating cells (LICs). Prdm16s expression in hematopoietic progenitor cells caused a myelodysplastic syndrome (MDS)-like disease that progressed to acute myelogenous leukemia (AML). The myeloid diseases caused by Prdm16s exhibited expansion of megakaryocyte-erythroid progenitors (MEPs) but not granulocyte-macrophage progenitors. MEPs from Prdm16s-induced leukemia possessed LIC potential, and expression of Prdm16s in normal MEPs was sufficient to convert them to myeloid LICs and blocked megakaryocytic/erythroid potential. Prdm16s induced the expression of myeloid master regulators, including PU.1 and C/EBP alpha, by interacting with their super enhancers. Ablation of myeloid master regulators attenuated the myeloid potential and reinstalled the megakaryocytic/erythroid potential of leukemic-MEPs in mouse models and in human AML with PRDM16 rearrangement. Our study demonstrates that oncogenic Prdm16 expression converts the fate of MEPs to a malignant myeloid fate by activating myeloid master transcription factors.
The TEENAGE study is a cross-sectional study comprising healthy Greek adolescents. The study was conducted according to the guidelines specified in the Declaration of Helsinki and all procedures involving human subjects were approved by the Institutional Review Board of Harokopio University and the Greek Ministry of Education, Lifelong Learning and Religious Affairs. The TEENAGE study target population comprised adolescent students aged 13 to 15 years attending the first three classes of public secondary schools located in the wider Athens area of Attica. The regions across Attica from which students were recruited were physically similar and all urban in nature. Sampling of regions and schools selected to participate was random. Students were enrolled from the wider urban region to ensure that they were coming from families with varying educational background and socio-economic status. Moreover, in order to exclude any vast economic disparities, all participating schools were exclusively public schools, which are free of charge. A total of twenty-four schools participated in the study out of 285 junior secondary public schools in Attica. Anthropometric, medical and dietary information was obtained. DNA samples were genotyped using Illumina HumanOmniExpress BeadChips (Illumina, San Diego, CA, USA) at the Wellcome Trust Sanger Institute, Hinxton, UK. Genotype calling algorithm used was Illuminus (Teo et al., 2007).
Colorectal cancer (CRC) patients with peritoneal metastases (CRPM) have limited treatment options and the lowest CRC survival rates. We trialed the possibility of organoid directed precision treatment for CRPM patients. CRPM organoids (peritonoids) isolated from patients underwent next-generation sequencing and medium-throughput drug panel testing ex vivo to identify specific drug sensitivities for each patient. We measured the utility of such a service including: success of peritonoid generation, time to cultivate peritonoids, reproducibility of the medium-throughput drug testing, and documented changes to clinical therapy as a result of the testing. Peritonoids were successfully generated and validated from 68% (19/28) of patients undergoing standard care. Genomic and drug profiling was completed within 8 weeks and a formal report ranking drug sensitivities was provided to the medical oncology team upon failure of standard care treatment. This resulted in a treatment change for 2 patients, one of whom had a partial response despite previously progressing on multiple rounds of standard care chemotherapy. The barrier to implementing this technology in Australia is the need for drug access and funding for off-label indications. In conclusion, our approach is feasible, reproducible and can guide novel therapeutic choices in this poor prognosis cohort, where new treatment options are urgently needed. This platform is relevant to many solid organ malignancies.
In acute myeloid leukemia (AML) with inv(3)(q21;q26) or t(3;3)(q21;q26), a translocated GATA2 enhancer drives oncogenic expression of EVI1. We generated an EVI1-GFP AML model and applied an unbiased CRISPR/Cas9 enhancer scan to uncover sequence motifs essential for EVI1 transcription. Using this approach, we pinpoint a single regulatory element in the translocated GATA2 enhancer that is critically required for aberrant EVI1 expression while being dispensable for GATA2 expression from its endogenous locus. This element contains a DNA binding motif for the transcription factor MYB that heavily occupies this site specifically at the translocated allele. MYB knockout as well as peptidomimetic blockade of p300-dependent MYB function resulted in downregulation of EVI1 but not of GATA2. Targeting MYB or mutating its DNA-binding motif within the GATA2 enhancer resulted in myeloid differentiation and cell death, suggesting that interference with MYB-driven EVI1 transcription provides a potential entry point for therapy of inv(3)/t(3;3) AMLs.
To explore tumor heterogeneity in sporadic human basal cell carcinoma tumors, we profiled three individual patient tumors by scRNA-Seq and scATAC-Seq. Basal cell carcinomas (BCCs) are driven by hedgehog signaling with GLI1 representing the key downstream transcription factor that drives tumor growth. GLI1 as such is a readout of active hedgehog signaling. We identified that LY6D can mark squamous populations such as in squamous cell carcinomas (SCCs) that are negative for GIL1 and hedgehog signaling. As such, both GLI1 and LY6D can be used as biomarkers of BCCs and SCCs and their related states.
Colorectal cancer (CRC) is characterized by functional intratumor heterogeneity that shares many similarites with the hierarchical organization of the normal intestinal epithelium. In order to relate transcriptional subtypes to functional tumor cell heterogeneity we applied scRNA-seq to 12 patient-derived CRC spheroid cultures. We identified shared expression programs that relate to intestinal lineages and revealed metabolic signatures that are linked to cancer cell differentiation. In addition, we validated and complemented sequencing results by quantitative microscopy using live-dyes and multiplexed RNA fluorescence in situ hybridization, thereby revealing metabolic compartmentalization and potential cell-cell interactions. FInally, we demonstrate functional differences between metabolically distinct lineage subtypes that might have strong implications for future treatment strategies of CRC.
Version 1 Whole genome sequencing was applied to tumor and adjacent normal lung tissue in an individual non-small-cell lung cancer patient. We present an analysis of somatic changes identified throughout the tumor genome, including single-nucleotide variants, copy number variants, and large-scale chromosomal rearrangements. Over 50,000 high-confidence single-nucleotide variants were identified, revealing evidence of substantial smoking-related DNA damage as well as distinct mutational pressures within the tumor resulting in uneven distribution of somatic mutations across the genome. Version 2 Lung cancer is a highly heterogeneous disease in terms of both underlying genetic lesions and response to therapeutic treatments. We performed deep whole genome sequencing and transcriptome sequencing on 19 lung cancer cell lines and 3 lung tumor/normal pairs. Overall, our data show that cell line models exhibit similar mutation spectra to human tumor samples. Smoker and never-smoker cancer samples exhibit distinguishable patterns of mutations. A number of epigenetic regulators are frequently altered by mutations or copy number changes. A systematic survey of splice-site mutations identified over 100 splice site mutations associated with cancer specific aberrant splicing, including mutations in several known cancer-related genes. Differential usages of splice isoforms were also studied. Taken together, these data present a comprehensive genomic landscape of a large number of lung cancer samples and further demonstrate that cancer specific alternative splicing is a widespread phenomenon that has potential utility as therapeutic biomarkers.
In childhood leukemia, a better genetic characterization is needed to define new clinic-biological entities, refine the risk-stratification of patients and help to reduce the toxicity by applying a risk-directed therapy. This project aims to obtain information that will allow us to personalize the management of pediatric patients with leukemia as much as possible, so that we can offer a complete diagnosis, a sensitive follow-up and a more targeted treatment to the real risk of each case. The use of massive genome analysis technologies such as transcriptome sequencing (RNA-Sequencing) will allow a comprehensive biological characterization of pediatric leukemia patients, especially those cases that we have not been able to characterize by conventional diagnostic techniques. We believe that the RNA-Seq technique will allow us to identify new biomarkers that will be useful for: 1) defining new biological entities with their own clinical behavior; 2) refining the stratification of patients into risk groups; 3) finding targets for a better follow-up of MRD and 4) identifying therapeutic targets for the application of targeted therapies to reduce toxicity. PI: Camós-Guijosa, Mireia; Vega-García, Nerea Funding: PI21/00213 Instituto de Salud Carlos III (ISCIII)
PTEN is one of most frequently altered tumor suppressor genes in malignant tumors. The dominant negative effect of PTEN alteration suggests that aberrant function of PTEN mutation might be more disastrous than deletion, the most frequent genomic event in glioblastoma (GBM). This study aimed to understand the functional properties of various PTEN missense mutations and to investigate their clinical relevance. The genomic landscape of PTEN alteration was analyzed using the Samsung Medical Center GBM cohort and validated via The Cancer Genome Atlas dataset. Several hot-spot mutations were identified, and their subcellular distributions and phenotypes were evaluated. We established a library of cancer cell lines that over-express these mutant proteins using the U87MG and patient-derived cell models lacking functional PTEN. PTEN mutations were categorized into two major subsets: missense mutations in the phosphatase domain and truncal mutations in the C2 domain. We determined the subcellular compartmentalization of four mutant proteins (H93Y, C124S, R130Q, and R173C) from the former group and found that they had distinct localizations; those associated with invasive phenotypes (‘edge mutations’) localized to the cell periphery, while the R173C mutant localized to the nucleus. Invasive phenotypes derived from edge substitutions were unaffected by an anti-PI3K/Akt agent but were disrupted by microtubule inhibitors. PTEN mutations exhibit distinct functional properties with regard to their subcellular localization. Further, some missense mutations (‘edge mutations’) in the phosphatase domain caused enhanced invasiveness associated with dysfunctional cytoskeletal assembly, thus suggesting it to be a potent therapeutic target.
The Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO) is a collaborative effort comprised of a coordinating center and scientific researchers from well-characterized cohort and case-control studies conducted in North America and Europe. This international consortium aims to accelerate the discovery of common and rare genetic risk variants for colorectal cancer by conducting large-scale meta-analyses of existing and newly generated genome-wide association study (GWAS) data, replicating and fine-mapping of GWAS discoveries, and investigating how genetic risk variants are modified by environmental risk factors. To expand these efforts, we assembled case-control sets or nested case-control sets from 20 different North American or European studies. Summary descriptions and study participant inclusions/exclusion criteria for each of these studies are detailed below. The Black Women's Health Study (BWHS): Is the largest follow-up study of the health of African-American women (Cozier et al., 2004; Rosenberg et al., 1995) [PMID: 15018884; PMID: 7722208]. The purpose is to identify and evaluate causes and preventives of cancers and other serious illnesses in African-American women. Among the diseases being studied are breast cancer, colorectal cancer, type 2 diabetes, uterine fibroids, systemic lupus erythematosus, and cardiovascular disease. The study began in 1995, when 59,000 black women from all parts of the United States enrolled through postal questionnaires. The women provided demographic and health data on the 1995 baseline questionnaire, including information on weight, height, smoking, drinking, contraceptive use, use of other selected medications, illnesses, reproductive history, physical activity, diet, use of health care, and other factors. The participants are followed through biennial questionnaires to determine the occurrence of cancers and other illnesses and to update information on risk factors. Self-reports of cancer are confirmed through medical records and state cancer registry records. Mouthwash-swish samples, as a source of DNA, were obtained from ~26,000 BWHS participants in 2002-2007. DNA was isolated from the mouthwash-swish samples at the Boston University Molecular Core Genetics Laboratory using the QIAAMP DNA Mini Kit (Qiagen). All incident colorectal cancer cases with a DNA sample were included in the present analysis. Two controls per case, selected from among BWHS participants free of colorectal cancer at end of follow-up, were matched to cases on year of birth (+/- 2 years) and geographical region of residence (Northeast, South, Midwest, and West). A total 209 colorectal cancer cases and 423 controls were sent for genotyping. Campaign Against Cancer and Heart Disease (CLUE II): The Campaign Against Cancer and Heart Disease, is a prospective cohort designed to identify biomarkers and other factors associated with risk of cancer, heart disease, and other conditions (Kakourou et al., 2015) [PMID: 26220152]. 32,894 participants were recruited from May through October 1989 from Washington County, Maryland and surrounding communities. Colorectal cancer cases (n = 297) and matched controls (n = 296) were identified between 1989 and 2000 among participants in the CLUE II cohort of Washington County, Maryland. Colorectal Cancer Study of Austria (CORSA): In the ongoing colorectal cancer study of Austria (CORSA), more than 13,000 Caucasian participants have been recruited within the province-wide screening project "Burgenland Prevention Trial of Colorectal Disease with Immunological Testing" (B-PREDICT) since 2003 (Hofer et al., 2011) [PMID: 21422235]. All inhabitants of the Austrian province Burgenland aged between 40 and 80 years are annually invited to participate in fecal immunochemical testing and haemoccult positive screening participants are invited for colonoscopy. CORSA includes genomic DNA and plasma of colorectal cancer cases, low-risk and high-risk adenomas, and colonoscopy-negative controls. Controls received a complete colonoscopy and were free of colorectal cancer or polyps. CORSA participants have been recruited in the four KRAGES hospitals in Burgenland, Austria, and additionally, at the Medical University of Vienna (Department of Surgery), the Viennese hospitals "Rudolfstiftung" and the "Sozialmedizinisches Zentrum Sud", and at the Medical University of Graz (Department of Internal Medicine). 1403 colorectal cancer and advanced colorectal adenoma cases, and 1404 matched controls were selected for the study. Distribution of factors sex and age (5 year strata) were evenly matched between cases and controls. Cancer Prevention Study II (CPS II): The CPS II Nutrition cohort is a prospective study of cancer incidence and mortality in the United States, established in 1992 and described in detail elsewhere (Calle et al., 2002; Campbell et al., 2014) [PMID: 12015775; PMID: 25472679]. At enrollment, participants completed a mailed self-administered questionnaire including information on demographic, medical, diet, and lifestyle factors. Follow-up questionnaires to update exposure information and to ascertain newly diagnosed cancers were sent biennially starting in 1997. Reported cancers were verified through medical records, state cancer registry linkage, or death certificates. The Emory University Institutional Review Board approves all aspects of the CPS II Nutrition Cohort. A total of 360 cases and 359 controls were selected for this study. Czech Republic Colorectal Cancer Study (Czech Republic CCS): Cases with positive colonoscopy results for malignancy, confirmed by histology as colon or rectal carcinomas, were recruited between September 2003 and May 2012 in several oncological departments in the Czech Republic (Prague, Pilsen, Benesov, Brno, Liberec, Ples, Pribram, Usti and Labem, and Zlin). Two control groups, sampled at the same time of cases recruitment, were included in the study. The first group consisted of hospital-based individuals with a negative colonoscopy result for malignancy or idiopathic bowel diseases. The reasons for the colonoscopy were: i) positive fecal occult blood test, ii) hemorrhoids, iii) abdominal pain of unknown origin, and iv) macroscopic bleeding. The second control group consisted of healthy blood donor volunteers from a blood donor center in Prague. All individuals were subjected to standard examinations to verify the health status for blood donation and were cancer-free at the time of the sampling. Details of CRC cases and controls have been reported previously (Vymetalkova et al., 2014; Naccarati et al., 2016; Vymetalkova et al., 2016) [PMID: 24755277; PMID: 26735576; PMID: 27803053]. All subjects were informed and provided written consent to participate in the study. They approved the use of their biological samples for genetic analyses, according to the Declaration of Helsinki. The design of the study was approved by the Ethics Committee of the Institute of Experimental Medicine, Prague, Czech Republic. All subjects included in the study were Caucasians and comprised 1792 cases and 1764 matched controls. Controls were matched to CRC cases as 1:1 ratio. Matching was done on age and sex. Age was matched on +-5 years, whereas sex was matched exactly. For the cases without matched controls, matching was done only on sex. Early Detection Research Network (EDRN): The aim of the EDRN initiative is to develop and sustain a biorepository for support of translational research (Amin et al., 2010) [PMID: 21031013]. High-quality biospecimens were accrued and annotated with pertinent clinical, epidemiologic, molecular and genomic information. A user-friendly annotation tool and query tool was developed for this purpose. The various components of this annotation tool include: CDEs are developed from the College of American Pathologists (CAP) Cancer Checklists and North American Association of Central Cancer Registries (NAACR) standards. The CDEs provides semantic and syntactic interoperability of the data sets by describing them in the form of metadata or data descriptor. A total of 352 colorectal case samples and 399 controls were selected for this study. Controls were matched to CRC cases based on age and sex. The EPICOLON Consortium (EPICOLON): The EPICOLON Consortium comprises a prospective, multicentre and population-based epidemiology survey of the incidence and features of CRC in the Spanish population (Fernandez-Rozadilla et al., 2013) [PMID: 23350875]. Cases were selected as patients with de novo histologically confirmed diagnosis of colorectal adenocarcinoma. Patients with familial adenomatous polyposis, Lynch syndrome or inflammatory bowel disease-related CRC, and cases where patients or family refused to participate in the study were excluded. Hospital-based controls were recruited through the blood collection unit of each hospital, together with cases. All of the controls were confirmed to have no history of cancer or other neoplasm and no reported family history of CRC. Controls were randomly selected and matched with cases for hospital, sex and age (+- 5 years). A total of 370 cases and 370 controls were selected for genotyping. Hawaii Adenoma Study: For this adenoma study, two flexible-sigmoidoscopy screening clinics were first used to recruit participants on Oahu, Hawaii. Adenoma cases were identified either from the baseline examination at the Hawaii site of the Prostate Lung Colorectal and Ovarian cancer screening trial during 1996-2000 or at the Kaiser Permanente Hawaii's Gastroenterology Screening Clinic during 1995-2007. In addition, starting in 2002 and up to 2007, we also approached for recruitment all eligible patients who underwent a colonoscopy in the Kaiser Permanente Hawaii Gastroenterology Department. Cases were patients with histologically confirmed first-time adenoma(s) of the colorectum and were of Japanese, Caucasian or Hawaiian race/ethnicity. Controls were selected among patients with a normal colorectum and were individually matched to the cases on age at exam, sex, race/ethnicity, screening date (+-3 months) and clinic and type of examination (colonoscopy or flexible sigmoidoscopy). We recruited 1016 adenoma cases (67.8% of all eligible) and 1355 controls (69.2% of all eligible); 889 cases and 1169 controls agreed to give a blood and 29 cases and 34 controls, a mouthwash sample. A total of 989 cases and 1185 controls were genotyped for this study. Columbus-area HNPCC Study (HNPCC, OSUMC): Patients with colorectal adenocarcinoma diagnosed at six participating hospitals were eligible for this study, regardless of age at diagnosis or family history of cancer. Patients with a clinical diagnosis of familial adenomatous polyposis were not eligible for this study. These six hospitals perform the vast majority of all operations for CRC in the Columbus metropolitan area (population 1.7 million). The institutional review board at all participating hospitals approved the research protocol and consent form in accordance with assurances filed with and approved by the United States Department of Health and Human Services. Briefly, during the period of January 1999 through August 2004, 1,566 eligible patients with CRC were accrued to the study (Hampel et al., 2008) [PMID 18809606]. A total of 1472 colorectal cancer samples had enough blood DNA remaining to be sent for genotyping. Control samples were provided by the Ohio State University Medical Center%#39;s (OSUMC) Human Genetics Sample Bank. The Columbus Area Controls Sample Bank is a collection of control samples for use in human genetics research that includes both donors' anonymized biological specimens and linked phenotypic data. The data and samples are collected under the protocol "Collection and Storage of Controls for Genetics Research Studies", which is approved by the Biomedical Sciences Institutional Review Board at OSUMC. Recruitment takes place in OSUMC primary care and internal medicine clinics. If individuals agree to participate, they provide written informed consent, complete a questionnaire that includes demographic, medical and family history information, and donate a blood sample. 4-7 ml of blood is drawn into each of 3 ACD Solution A tubes and is used for genomic DNA extraction and the establishment of an EBV-transformed lymphoblastoid cell culture, cell pellet in Trizol, and plasma. Controls were matched to CRC cases as 1:1. Matching was done on age at reference time (age_ref), race, and sex. Age_ref was matched on +-5 years. Sex and race were matched exactly. For the cases without matched controls, matching was done only on sex and race with 1:1 ratio. Since controls are fewer than cases, one control is matched on 2 cases at most. Health Professionals Follow-up Study (HPFS): A parallel prospective study to the NHS (Nurses' Health Study). The HPFS cohort comprised 51,529 men aged 40-75 who, in 1986, responded to a mailed questionnaire (Rimm et al., 1990) [PMID: 2090285]. Participants provided information on health related exposures, including current and past smoking history, age, weight, height, diet, physical activity, aspirin use, and family history of colorectal cancer. Colorectal cancer and other outcomes were reported by participants or next-of-kin and were followed up through review of the medical and pathology record by physicians. Overall, more than 97% of self-reported colorectal cancers were confirmed by medical record review. Information was abstracted on histology and primary location. Incident cases were defined as those occurring after the subject provided the blood sample. Prevalent cases were defined as those occurring after enrollment in the study but before the subject provided the blood sample. Follow-up evaluation has been excellent, with 94% of the men responding to date. Colorectal cancer cases were ascertained through January 1, 2008. In 1993-1995, 18,825 men in the HPFS mailed blood samples by overnight courier, which were aliquoted into buffy coat and stored in liquid nitrogen. In 2001-2004, 13,956 men in the HPFS who had not provided a blood sample previously mailed in a swish-and-spit sample of buccal cells. Incident cases were defined as those occurring after the subject provided a blood or buccal sample. Prevalent cases were defined as those occurring after enrollment in the study in 1986, but before the subject provided either a blood or buccal sample. After excluding participants with histories of cancer (except nonmelanoma skin cancer), ulcerative colitis, or familial polyposis, case-control sets were previously constructed. In addition to colorectal cancer cases and controls, a set of adenoma cases and matched controls with available DNA from buffy coat were selected for genotyping. Over the follow-up period, data were collected on endoscopic screening practices and, if individuals had been diagnosed with a polyp, the polyps were confirmed to be adenomatous by medical record review. Adenoma cases were ascertained through January 1, 2008. A separate case-control set was constructed of participants diagnosed with advanced adenoma matched to control participants who underwent a lower endoscopy in the same time period and did not have an adenoma. Advanced adenoma was defined as an adenoma 1 cm or larger in diameter and/or with tubulovillous, villous, or highgrade dysplasia/carcinoma-in-situ histology. Matching criteria included year of birth (within 1 year) and month/ year of blood sampling (within 6 months), the reason for their lower endoscopy (screening, family history, or symptoms), and the time period of any prior endoscopy (within 2 years). Controls matched to cases with a distal adenoma either had a negative sigmoidoscopy or colonoscopy examination, and controls matched to cases with proximal adenoma all had a negative colonoscopy. In total, 159 advanced adenoma cases and 109 controls were selected for genotyping. Leeds Colorectal Cancer Study (LCCS): Following local ethical approval, colorectal cancer cases were recruited from 1997 until 2012 in Leeds, UK through surgical clinics. Initially, funding was provided by the UK Ministry of Agriculture, Farming and Fisheries (subsequently the Food Standards Agency) and Imperial Cancer Research Fund (subsequently Cancer Research UK). Recruitment also occurred similarly in Dundee, Perth and York between the periods of 1997 and 2001 using the same protocol and the data and samples were combined. Pathologically confirmed cases were consented at outpatient clinics, providing information on known and postulated risk factors for colorectal cancer (diet, lifestyle and family history) as well as providing a blood sample for DNA. Exclusion criteria included pre-existing diverticular disease and an inability to complete the questionnaire. The General Practitioners of cases (all UK residents have a nominated General Practitioner to whom to refer initial medical queries) and these GPs were asked to send letters to other persons on their patient list of the same gender and born within 5 years of the case. Subsequently to enhance the number of controls, we systematically invited patients from selected GP practices. Diet was assessed in cases and controls using an extensive dietary and lifestyle questionnaire modified by that produced by the European Prospective Investigation in Cancer (EPIC). The frequency that each specific food items were eaten was recorded and we also obtained average fruit and vegetable consumption as a cross-check. In total, 1591 cases and 739 controls provided a DNA sample. The North Carolina Colon Cancer Studies (NCCCS I/II): The North Carolina Colon Cancer Studies (NCCCS I- colon and NCCCS II-rectal) were population-based case-control studies conducted in 33 counties of North Carolina. Cases were identified using the rapid case ascertainment system of the North Carolina Central Cancer Registry. Patients with a first diagnosis of histologically confirmed invasive adenocarcinoma of the colon (cecum through sigmoid colon) between October 1996 and September 2000 were classified as potential cases in the NCCCS I. The NCCCS II included patients with a first diagnosis of histologically confirmed invasive adenocarcinoma of the sigmoid colon, rectosigmoid, or rectum (hereafter collectively referred to as rectal cancer) between May 2001 and September 2006. Additional eligibility requirements were: aged 40-80 years, residence in one of the 33 counties, ability to give informed consent and complete an interview, had a driver's license or identification card issued by the North Carolina Department of Motor Vehicles (if under the age of 65), and had no objections from the primary physician in regards to contacting the individual. Controls, identified and sampled during the respective study dates, were selected from two sources. Potential controls under the age of 65 were identified using the North Carolina Department of Motor Vehicles records. For those 65 years and older, records from the Center for Medicare and Medicaid Services were used. Controls were matched to cases using randomized recruitment strategies. Recruitment probabilities were done using strata of 5-year age, sex, and race groups. Dietary information was collected using a modified version of the semiquantitative food frequency questionnaire developed at the National Cancer Institute. In addition, participants were asked about vitamin and mineral supplementation, special diets, restaurant eating, sodium use, and fats used in cooking. In NCCCS I, 515 colorectal cases and 687 matched controls were sent for genotyping. In NCCCS II, 796 colorectal cases and 823 controls were sent from the NCCCS II for genotyping. Controls were matched to CRC cases as 1:1 ratio. Matching was done on age, race, and sex. Age was matched on +-5 years. Race and sex was matched exactly. For the cases without matched controls, matching was done only on sex and race. Nurses Health Study (NHS): The NHS cohort began in 1976 when 121,700 married female registered nurses age 30-55 years returned the initial questionnaire that ascertained a variety of important health-related exposures (Belanger et al., 1978) [PMID: 248266]. Since 1976, follow-up questionnaires have been mailed every 2 years. Colorectal cancer and other outcomes were reported by participants or next-of-kin and followed up through review of the medical and pathology record by physicians. Overall, more than 97% of self-reported colorectal cancers were confirmed by medical-record review. Information was abstracted on histology and primary location. The rate of follow-up evaluation has been high: as a proportion of the total possible follow-up time, follow-up evaluation has been more than 92%. Colorectal cancer cases were ascertained through June 1, 2008. In 1989 -1990, 32,826 women in NHS I mailed blood samples by overnight courier, which were aliquoted into buffy coat and stored in liquid nitrogen. In 2001-2004, 29,684 women in NHS I who did not previously provide a blood sample mailed a swish-and-spit sample of buccal cells. Incident cases were defined as those occurring after the subject provided a blood or buccal sample. Prevalent cases were defined as those occurring after enrollment in the study in 1976 but before the subject provided either a blood or buccal sample. After excluding participants with histories of cancer (except nonmelanoma skin cancer), ulcerative colitis, or familial polyposis, case-control sets were previously constructed from which DNA was isolated from either buffy coat or buccal cells for genotyping. In addition to colorectal cancer cases and controls, a set of advanced adenoma cases and matched controls with available DNA from buffy coat were selected for genotyping. Over the follow-up period, data were collected on endoscopic screening practices and, if individuals had been diagnosed with a polyp, the polyps were confirmed to be adenomatous by medical record review. Adenoma cases were ascertained through June 1, 2011. A separate case-control set was constructed of participants diagnosed with advanced adenoma matched to control participants who underwent a lower endoscopy in the same time period and did not have an adenoma. Advanced adenoma was defined as an adenoma more than 1 cm in diameter and/or with tubulovillous, villous, or high-grade dysplasia/carcinoma-in-situ histology. Matching criteria included year of birth (within 1 year) and month/year of blood sampling (within 6 months), the reason for their lower endoscopy (screening, family history, or symptoms), and the time period of any prior endoscopy (within 2 years). Controls matched to cases with a distal adenoma either had a negative sigmoidoscopy or colonoscopy examination, and controls matched to cases with proximal adenoma all had a negative colonoscopy. A total of 272 cases and 236 matched controls were sent to CIDR for the advanced adenoma case-control set. Northern Swedish Health and Disease Study (NSHDS): Comprises over 110,000 participants, including approximately one third with repeated sampling occasions, from three population-based cohorts (Dahlin et al., 2010; Myte et al., 2016) [PMID: 20197478; PMID: 27367522]. The largest is the ongoing Vasterbotten Intervention Programme, in which all residents of Vasterbotten County are invited to a health examination upon turning 30 (some years), 40, 50 and 60 years of age. Extensive measured and self-reported health and lifestyle data, as well as blood samples for central biobanking in Umea, Sweden, are collected at the health exam. Leucocyte DNA samples for 1:1-matched CRC case-control sets from the NSHDS, of which 878 samples are included in this study, have been selected for genotyping. This is in addition to 354 samples from the NSHDS previously analyzed as part of the multicenter EPIC cohort. Cancer-specific and overall survival data are available for all patients. For at least 425 patients, archival tumor tissue has been analyzed for the BRAF V600E mutation and by sequencing codon 12 and 13 for KRAS mutations, as well as for MSI screening status by immunohistochemistry and for an eight-gene CIMP panel using quantitative real-time PCR (MethyLight). Ohio Colorectal Cancer Prevention Initiative (OCCPI, OSUMC): OCCPI (ClinicalTrials.gov identifier: NCT01850654) is a population-based study of colorectal cancer patients diagnosed in one of 51 hospitals throughout the state of Ohio from January 1, 2013 through December 31, 2016. The OCCPI was created to decrease CRC incidence in Ohio by identifying patients with hereditary predisposition (statewide universal tumor screening for newly diagnosed CRC patients), increase colonoscopy compliance for first-degree relatives of CRC patients, and encourage future research through the creation of a biorepository. The 51 Ohio hospitals participating in the OCCPI were selected to represent a cross-section of clinical centers in the state based on high reported volume of CRC patients, affiliation with a high volume hospital, or interest in participation. Institutional Review Board (IRB) approval was obtained by the individual hospitals, Community Oncology Programs, or by ceding review to the OSU IRB. Written informed consent was obtained. A total of 2139 colorectal cases were genotyped. Patients were considered eligible for this study if they were age 18 or older at the time of enrollment, if they had a surgical resection (or biopsy if unresectable) in the state of Ohio demonstrating an adenocarcinoma of the colorectum from 1/1/13 - 12/31/16. Matched control samples were selected from the Ohio State University Medical Center's (OSUMC) Human Genetics Sample Bank in an identical way to the selection for the Columbus-area HNPCC Study (please refer to the description for the Columbus-area HNPCC Study). Prostate, Lung, Colorectal and Ovarian Cancer Screening Trail (PLCO): PLCO enrolled 154,934 participants (men and women, aged between 55 and 74 years) at ten centers into a large, randomized, two-arm trial to determine the effectiveness of screening to reduce cancer mortality. Sequential blood samples were collected from participants assigned to the screening arm. Participation was 93% at the baseline blood draw. In the observational (control) arm, buccal cells were collected via mail using the "swish-and-spit" protocol and participation rate was 65%. Details of this study have been previously described (Huang et al., 2016) [PMID: 27673363] and are available online (http://dcp.cancer.gov/plco). For this study 1651 advanced adenoma cases and 1392 controls were selected for genotyping. Selenium and Vitamin E Prevention Trial (SELECT): The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was a double-blind, placebo controlled clinical trial which explored using selenium and vitamin E alone and in combination to prevent prostate cancer in healthy men (Lippman et al., 2009) [PMID: 19066370]. Secondary endpoints included the prevention of colorectal and lung cancers. SELECT was conducted at 427 sites and centers in the United States, Canada and Puerto Rico; 35,533 men 55 years and older (50 or older if African American) were randomized beginning August 22, 2001. Supplementation was discontinued on October 23, 2008 due to futility. 308 colorectal cancer cases and 308 matched controls were selected from the SELECT population and sent for genotyping. Screening Markers For Colorectal Disease Study and Colonoscopy and Health Study (SMS-REACH): Details on this study population were previously reported (Burnett-Hartman et al., 2014) [PMID: 24875374]. Participants were enrollees in an integrated health-care delivery system in western Washington State (Group Health Cooperative, Seattle, Washington) aged 24-79 years who underwent an index colonoscopy for any indication between 1998 and 2007 and donated a buccal-cell or blood sample for genotyping analysis. Study recruitment took place in 2 phases, with phase 1 occurring in 1998-2003 and phase 2 occurring in 2004-2007. Persons who had undergone a colonoscopy less than 1 year prior to the index colonoscopy, persons with inadequate bowel preparation for the index colonoscopy, and persons with a prior or new diagnosis of colorectal cancer, a familial colorectal cancer syndrome (such as familial adenomatous polyposis), or another colorectal disease were ineligible. Patients diagnosed with adenomas or serrated polyps and persons who were polyp-free at the index colonoscopy (controls) were systematically recruited during both phases of recruitment. Approximately 75% agreed to participate and provided written informed consent. Based on medical records, persons who agreed to participate and those who refused study participation were similar with respect to age, sex, and colorectal polyp status. Study protocols were approved by the institutional review boards of the Group Health Cooperative and the Fred Hutchinson Cancer Research Center (Seattle, Washington). A total of 575 cases and 508 matched were selected for the study. Controls were matched to CRC cases as 1:1 ratio. Matching was done on age_ref, race, and sex. Age_ref was matched on +-5 years. The Women's Health Initiative (WHI): WHI is a long-term national health study that has focused on strategies for preventing heart disease, breast and colorectal cancer, and osteoporotic fractures in postmenopausal women. The original WHI study included 161,808 postmenopausal women enrolled between 1993 and 1998. The Fred Hutchinson Cancer Research Center in Seattle, WA serves as the WHI Clinical Coordinating Center for data collection, management, and analysis of the WHI. The WHI has two major parts: a partial factorial randomized Clinical Trial (CT) and an Observational Study (OS); both were conducted at 40 Clinical Centers nationwide. The CT enrolled 68,132 postmenopausal women between the ages of 50-79 into trials testing three prevention strategies. If eligible, women could choose to enroll in one, two, or all three of the trial components. The components are: Hormone Therapy Trials (HT): This double-blind component examined the effects of combined hormones or estrogen alone on the prevention of coronary heart disease and osteoporotic fractures, and associated risk for breast cancer. Women participating in this component with an intact uterus were randomized to estrogen plus progestin (conjugated equine estrogens [CEE], 0.625 mg/d plus medroxyprogesterone acetate [MPA] 2.5 mg/d] or a matching placebo. Women with prior hysterectomy were randomized to CEE or placebo. Both trials were stopped early, in July 2002 and March 2004, respectively, based on adverse effects. All HT participants continued to be followed without intervention until close-out. Dietary Modification Trial (DM): The Dietary Modification component evaluated the effect of a low-fat and high fruit, vegetable and grain diet on the prevention of breast and colorectal cancers and coronary heart disease. Study participants were randomized to either their usual eating pattern or a low-fat dietary pattern. Calcium/Vitamin D Trial (CaD): This double-blind component began 1 to 2 years after a woman joined one or both of the other clinical trial components. It evaluated the effect of calcium and vitamin D supplementation on the prevention of osteoporotic fractures and colorectal cancer. Women in this component were randomized to calcium (1000 mg/d) and vitamin D (400 IU/d) supplements or a matching placebo. The Observational Study (OS)examines the relationship between lifestyle, environmental, medical and molecular risk factors and specific measures of health or disease outcomes. This component involves tracking the medical history and health habits of 93,676 women not participating in the CT. Recruitment for the observational study was completed in 1998 and participants were followed annually for 8 to 12 years. All centrally confirmed cases of invasive colorectal cancers, or deaths from colorectal cancer were selected as potential cases from September 30, 2015 database. Controls were participants free of colorectal cancer (invasive or in situ) as of September 30, 2015. Potential cases and controls were excluded if they (1) were non-White; (2) had history of colorectal cancers at baseline; (3) lost to follow-up after enrollment; (4) DbGAP ineligible; (5) had <1.25ug of DNA; (6) selected for WHI study M26 Phase I or II; (7) selected for WHI study AS224 and also included in the imputation project. A total of 578 cases and 104,429 controls met the eligibility criteria. Each case was matched with 1 control (1:1) that exactly met the following matching criteria: age (+-5 years), 40 randomization centers (exact), WHI date (+-3 years), CaD date (+-3 years), OS flag (exact), HRT assignments (exact), DM assignments (exact), and CaD assignments (exact). Control selection was done in a time-forward manner, selecting one control for each case from the risk set at the time of the case's event. The matching algorithm was allowed to select the closest match based on a criteria to minimize an overall distance measure (Bergstralh EJ, Kosanke JL. Computerized matching of cases to controls. Technical Report #56, Department of Health Sciences Research, Mayo Clinic, Rochester MN. April 1995). Each matching factor was given the same weight. When exact matches could not be found, the matching criteria were gradually relaxed among unmatched cases and controls until all cases had found matched controls. Using the matching criteria specified above, 559 of the 578 eligible cases found exact matches. The matching criteria was then relaxed to : Age+-5, randomization centers, WHI date +- 3 years, CaD date +- 3 years, OS flag, HRT flag, DM flag, CaD flag. 17 of the remaining 19 unmatched cases found matched controls. By matching on Age+-5, randomization centers, WHI date +- 3 years, CaD date +- 3 years, OS flag, HRT flag, the remaining 2 unmatched cases found their matches.
Loss of the tumor suppressors RB1 and TP53 and MYC amplification are frequent oncogenic events in small cell lung cancer (SCLC). We show that Myc expression cooperates with Rb1 and Trp53 loss in the mouse lung to promote aggressive, highly metastatic tumors, that are initially sensitive to chemotherapy followed by relapse, similar to human SCLC. Importantly, MYC drives a neuroendocrine-low “variant” subset of SCLC with high NEUROD1 expression corresponding to transcriptional profiles of human SCLC. Targeted drug screening reveals that SCLC with high MYC expression is vulnerable to Aurora kinase inhibition, which combined with chemotherapy strongly suppresses tumor progression and increases survival. These data identify molecular features for patient stratification and uncover a novel targeted treatment approach for MYC-driven SCLC.
Circulating tumor-derived DNA testing for cancer screening has recently been demonstrated in a prospective study on identification of nasopharyngeal carcinoma (NPC) among 20,174 asymptomatic individuals. Plasma EBV DNA, a marker for NPC, was detected using real-time PCR. While plasma EBV DNA was persistently detectable in 97.1% of the NPCs identified, ∼5% of the general population had transiently detectable plasma EBV DNA. We hypothesized that EBV DNA in plasma of subjects with or without NPC may have different molecular characteristics. We performed target-capture sequencing of plasma EBV DNA and identified differences in the abundance and size profiles of EBV DNA molecules within plasma of NPC and non-NPC subjects. NPC patients had significantly higher amounts of plasma EBV DNA, which showed longer fragment lengths. Cutoff values were established from an exploratory dataset and tested in a validation sample set. Adopting an algorithm that required a sample to concurrently pass cutoffs for EBV DNA counting and size measurements, NPCs were detected at a positive predictive value (PPV) of 19.6%. This represented superior performance compared with the PPV of 11.0% in the prospective screening study, which required participants with an initially detectable plasma EBV DNA result to be retested within 4 weeks. The observed differences in the molecular nature of EBV DNA molecules in plasma of subjects with or without NPC were successfully translated into a sequencing-based test that had a high PPV for NPC screening and achievable through single time-point testing.
The HCI-PDX Trial Center for Breast Cancer Therapy study is a collection of patient-tumor samples that are serially established as patient-derived tumor xenografts (human tumor in mouse) and matching organoids. For this study, we describe valuable methods and resources to generate organoids and use them as cost-effective models for precision drug screens. This study leveraged whole-exome sequencing, RNAseq, and SNP-array data to illustrate how the heterogeneity of tumors is preserved in xenograft and organoid models. Sequencing files are provided for whole-exome and RNAseq data. Processed copy number variant calls from the SNP arrays are also available. A full description of the study can be found in the article entitled, "A human breast cancer-derived xenograft and organoid platform for drug discovery and precision oncology," written by Guillen et al., 2022 in Nature Cancer (PMID: 35221336).
Colorectal cancer, a leading cause of cancer-related mortality due to distant metastases, is driven by activating mutations in the Wnt and MAPK pathways. Understanding the interplay between these crucial pathways during metastatic progression is essential for developing effective treatments. Here we developed an immunocompetent mouse model of metastatic colorectal cancer using in vivo orthotopic passaging. We demonstrate that highly metastatic tumor cells exhibit chromosomal amplifications in MAPK pathway genes, leading to increased MAPK activity, which in turn suppresses Wnt-associated transcriptional programs, including stem cell-associated genes. Inhibiting mutant KrasG12D effectively reversed this metastatic transcriptional state, reducing MAPK-driven gene expression and restoring Wnt activity. Notably, this treatment significantly curtailed lung metastases and reduced liver metastases during early seeding stages. Analysis of CRC patient data revealed that high MAPK activity and the associated metastatic gene signature correlated with poorer survival outcomes. These findings underscore that the plasticity of metastasis-initiating cells in CRC arises from the opposing roles of MAPK and Wnt signaling, despite their synergistic importance in colon tumor initiation.
Sialylation, and its modifications, have important consequences for development, differentiation and immune system regulation in nearly all human tissues. An accounting of all the genes responsible for modifying sialic acids is incomplete, with only one pathway for O-acetylation being well-defined in humans. Using whole genome sequencing of normal human colorectal tissue we identify a haplotype on chromosome 11 that is associated with differences in mild periodic acid Schiff staining (mPAS), a marker of acetylation of sialic acids. Of the genes in this region, only SNPs from NXPE1 correlate perfectly in a validation data set. NXPE1 protein expression by IHC also correlates with mPAS staining patterns in homozygous, as well as heterozygous colon crypts that have undergone spontaneous gain of the mPAS phenotype. Manipulation of NXPE1 expression with CRISPR-Cas9 causes changes to modified sialic acid levels in both 2D cell line and 3D normal colon organoid models. These findings suggest NXPE1 may cause O-acetylation of sialic acids in colorectal tissue, potentially defining NXPE as a new family of sialic acid-modifying genes.
To study the evolutionary processes that drive malignant transformation in IDH-mutant astrocytomas, we performed multi-omics on a large cohort of matched initial and recurrent tumor samples. We find that genome-wide DNA-methylation levels decreased over time, mainly in patients with high-grade recurrences. DNA-demethylation was lifted from specific loci associated with DNA replication, and was associated with upregulation of cell cycling associated genes. Upregulation of cell cycling genes occurred predominantly in proliferating tumor cells, and was associated with tumor grade. Temporal DNA-demethylation and upregulation of cell cycling were hardly affected by chemo- and/or radiotherapy, indicating treatment does not affect the course of disease. Further, we defined a DNA-methylation based signature associated with tumor grade and poor prognostic genetic events, with a prognostic power stronger than CDKN2A/B deletion. We validated its prognostic power on primary tumor samples of patients included in the CATNON randomized phase 3 clinical trial. Therefore this model can serve as a molecular grading marker for IDH-mutant astrocytomas.
High-throughput linking of T cell receptor (TCR) sequences to their binding antigens is vital for immune profiling, yet challenging. We present Tetramer associated TCR Sequencing (TetTCR-Seq) to address this challenge. Binding is determined using a library of DNA-barcoded antigen tetramers that are rapidly and inexpensively generated using an in vitro transcription/translation platform. We included CMV+ donors (CMV seropositive donors who are infected with Cytomegalovirus) to screen for CMV specific TCRs.
Bipolar disorder is a complex psychiatric disease for which few causative genes have been discovered. Targeted sequencing of bipolar cases and unaffected controls was performed to elucidate the contribution of rare variants to bipolar disorder. This study included the standard exome targets as well as genes involved in synaptic function and genes previously implicated in bipolar disorder.