3775 results for "*oma"

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• Urothelial Cancer - Genomic Analysis to Improve Patient Outcomes and Research (UC-GENOME): a Bladder Cancer Advocacy Network (BCAN)-Led Collaborative Research Pilot Study - for Samples Collected at Johns Hopkins

  UC-GENOME is a real-world cohort of patients with metastatic urothelial carcinoma (UC). The study consisted of two co-equal aims: 1) to provide targeted DNA sequencing for clinical decision making at no cost to patients; and 2) to create a resource for collaborative translational science including a clinically annotated biobank. The submitted data represents the foundational analysis of 218 patients accrued at 7 academic medical centers. The analysis includes 176 patients with both targeted DNA sequencing and RNA sequencing. The genomic data was combined with clinical variables to model response to chemotherapy and immune checkpoint inhibitors (ICI).The larger dataset for this study can be found in dbGaP study phs003066.

  Study phs003094

• Integration of Clinical and Molecular Biomarkers for Melanoma Survival (Berwick)

  The long-term goal of the InterMEL Program Project: Integration of Clinical and Molecular Biomarkers for Melanoma Survival is to identify molecular and clinical factors that predict survival of melanoma patients. Our overarching hypothesis is that we can identify factors in the primary melanoma tumor that will lead to more aggressive disease. Melanoma patients diagnosed at American Joint Committee on Cancer (AJCC) tumor, lymph nodes, and metastases (TNM) stages IIA/IIB/IIC/IIIA/IIIB/IIIC/IIID display highly variable clinical outcomes and responses to therapy. We wish to identify robust and reproducible biomarkers or sets of classifiers that distinguish patients likely to have poor prognosis. These biomarkers will help establish targets for adjuvant therapies for this set of patients before the tumors metastasize. Aim 1. Classify actionable somatic mutations, and copy number variations (CNVs) in relationship to melanoma survival. In Project 1, Targeted Sequencing and Clinicopathology to Evaluate Primary Melanoma Molecular Subtypes and Outcomes, we will profile 468 genes using the MSKIMPACT ™ assay and identify somatic mutations and CNVs associated with melanoma-specific survival, as well as their co-occurrence with other mutations, in 1,000 tumors from patients at AJCC TNM stages IIA-IIID: approximately 500 from patients who died with melanoma within five years and approximately 500 from individuals who have lived at least five years. We will also evaluate the joint effects of somatic mutations, CNVs and pathologic characteristics associated with good and poor outcomes. Aim 2. Identify primary melanoma DNA methylation profiles to evaluate subtypes and survival. Although it has been established that melanomas frequently have aberrant DNA methylation, it is unknown if DNA methylation in primary melanomas predicts outcome. In Project 2, Primary Melanoma DNA Methylation Profiling for Evaluating Subtypes and Survival, we will profile the same primary melanomas as in Project 1 with Illumina Infinium 850K methylation arrays. We expect to: identify and characterize DNA methylation-based melanoma subclasses; train, test and validate a CpG signature prognostic for survival from melanoma; determine whether this profile adds information to outcome prediction beyond AJCC TNM staging. This project is based on the hypothesis that DNA methylation in primary melanoma will define subgroups (including a poor-prognosis CIMP – ‘CpG island methylator phenotype' subtype) and that a CpG signature will be prognostic for melanoma survival. Aim 3. Define microRNA expression changes in relation to melanoma survival. MicroRNAs have been associated with poor prognosis in melanoma, as well as in other cancers. In Project 3, Prognostic and Functional Role of a Gene Expression Signature in Melanoma Patients, we hypothesize that altered miRNA expression, captured at the time of diagnosis, may contribute to the aggressive behavior of a subset of early stage primary melanomas. We will profile the same primary melanomas as in Projects 1 and 2 with a Nanostring assay. This project will define and validate a tissue-based microRNA signature in conducted to determine whether the prognostic miRNA signature, as well as other candidate genes emerging from other projects, contribute to melanoma survival. Aim 4. Integrate data from multiple platforms to identify melanoma subtypes and survival. Despite substantial literature on gene tumor mutation-, methylation- and gene expression-based prognostic and predictive signatures for melanoma, few such signatures are used in clinical practice. Project 4, Multiplatform Analysis of Melanoma Molecular Subtypes and Patient Survival Outcome, will use novel integrative clustering methods to identify molecular subtypes of melanoma jointly defined across these platforms.

  Study phs003099

• Whole-Genome Sequencing Analysis of Extrachromosomal DNA with Amplicon Architect

  The study is related to our manuscript entitled "Single-cell genetic heterogeneity linked to immune infiltration in glioblastoma". Using multiplexed FISH analysis of 3-4 tumor cores from 17 glioblastoma formalin-fixed paraffin-embedded (FFPE) tumors, we identified two classes of tumors based on single cell co-occurrence of EGFR and CDK4 amplification. Tumors with a low odds ratio for finding EGFR and CDK4 amplified in the same cell (ORlow tumors) had higher EGFR copy number and higher diversity of copy number in cells harboring EGFR amplification. This suggested that in ORlow tumors EGFR is likely present on extrachromosomal DNA. To test this hypothesis, we performed whole genome sequencing on DNA extracted from FFPE slides from 3 ORlow samples and 3 ORhigh samples and used AmpliconArchitect to investigate the structure of the EGFR amplicon. We found multiple breakpoints and high complexity structure in the 3 tested ORlow samples, but not in the ORhigh samples, supporting the possibility of an extrachromosomal nature of EGFR amplification in the first group.

  Study phs003100

• Single Cell Analysis of Sporadic Human Basal Cell Carcinomas

  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.

  Study phs003103

• 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

• Childhood Cancer Data Initiative (CCDI): Clonal Evolution During Metastatic Spread in High-Risk Neuroblastoma

  The goal of this study is to deliver a detailed characterization of the patterns of disease dissemination at diagnosis, during progression and in response to therapy in high-risk neuroblastoma. Longitudinal and spatially distinct tumors were collected from patients. Clinical data includes diagnosis and treatment information. Biospecimen data includes whole genome sequencing (WGS) and whole transcriptome sequencing (WTS).

  Study phs003111

• Multiregional Single-Cell Transcriptomic Analysis of Liver Cancer

  In this study, we performed single-cell transcriptomic profiling of human liver tissues collected from hepatocellular carcinoma and intrahepatic cholangiocarcinoma patients. A total of seven primary liver cancer patients enrolled in this study. Samples were collected from multiple regions, including tumor core, tumor border and adjacent non-tumor tissue. The 10x Genomics platform was used to generate single cell 5' libraries. The Illumina NovaSeq 6000 platform was employed for sequencing.

  Study phs003117

• Genetic Progression of Head and Neck Squamous Cell Carcinoma

  These data are tumor/normal-matched exome sequencing results on 45 participants (median age of 58.6 years) treated for squamous cell carcinoma of the oropharynx at Mass Eye and Ear (MEE; Boston, MA, USA). Some tumors had two portions sequenced separately. All research complied with all relevant ethical regulations. Human subject research on patients at MEE was approved by the MEE Human Studies Committee under protocol HSC 11-024H, with informed consent obtained from participants. Participants were not compensated. Clinical data, including HPV status, were abstracted from patient records. Sequencing and clinical data were combined with TCGA data on 486 cases of head and neck squamous cell carcinoma (HNSCC). The PhylogicNDT suite of genomic analysis tools was used to infer the relative timing of genetic events during tumor progression for major molecularly defined classes of HNSCC: HNSCC negative for human papillomavirus (HPV), HPV-associated HNSCC, and HPV-negative HNSCC involving mutations in CASP8, NSD1, and NOTCH1. The timing of the development of whole-genome somatic events leading to tetraploidy or triploidy and to increased measures of intratumor genetic heterogeneity was determined. Associations of heterogeneity measures with clinical outcomes were assessed. The analysis identified genes with early mutations that likely play roles in HPV-tumor initiation (FBXW7, NOTCH1, CASP8, FAT1, NSD1, HRAS, EP300, CREBBP, KMT2D). Genes with mutations at later median relative timing (PK3CA, NFE2L2, HLA-A, SPEN, and KMT2C) were more likely to be important for progressing to later stages of the disease. Gain of chromosome arm 3q and loss of arm 11q were found to occur more frequent in HPV+ HNSCC cases. A high prevalence of 3p and 17p loss were also observed in HPV+ HNSCC cases.

  Study phs003139

• Tissue Sampling and Biorepository to improve Cancer Cell Therapy

  This study focuses on the elucidation of determinants of response and resistance to anti-CD19 CAR T-cells in large B-cell lymphoma. Plasma samples were collected prior to treatment and serially post CAR T-cell infusion. Pre-treatment and relapse tumor samples were also obtained as available. Germ-line DNA isolated from Peripheral Blood Mononuclear Cells (PBMCs) was collected for all patients when available. Circulating tumor DNA (ctDNA) and tumor DNA were sequenced using a target hybrid capture oligonucleotide pool. RNA-Seq was also performed on tumor isolated RNA. The authors identified several recurrent genomic alterations associated with relapse, and identified molecular thresholds that were predictive of response.

  Study phs003145

• NCT03343197: Clinical Biomarker Data

  Patients with IDH1-mutated low-grade glioma were treated with AG-120 (ivosidenib), AG-881 (vorasidenib), or Placebo for 28 days before surgical resection. A portion of the surgical sample was submitted for exome capture-based transcriptome sequencing (Personalis ACE Whole Transcriptome). Following surgery, subjects had the option to continue (or initiate) treatment with AG-120 or AG-881.This dataset comprises next-generation sequencing data from biopsies obtained in the clinical trial: NCT03343197 (Study of AG-120 and AG-881 in Subjects with Low Grade Glioma).

  Study phs003148

• Neoantigen-Targeted CD8+ T-Cell Responses 1 With PD-1 Blockade Therapy

  Background: The primary target of T-cell responses induced against cancer cells are peptides derived from non-synonymous mutations presented by HLA (neoantigens). However, the large diversity of HLA alleles and restricted availability of clinical samples have limited the study of the specificity and the evolution over time of the neoantigen-specific T cell responses induced after treatment with immune checkpoint blockade (ICB) immunotherapy. Methods: We applied a newly developed neoepitope-specific T cell isolation technology to perform a longitudinal landscape analysis of the neoepitope-specific T cells in peripheral blood and tumor from 11 patients with metastatic melanoma; 7 with response and 4 with no response to ICB. Briefly, first using computational prediction, the putative neoantigens in each patient were ranked based on affinity for the patient's HLA and expression levels. Then hundreds of barcoded capture reagents consisting of the patient HLA class I subtypes loaded with the corresponding predicted neoantigen were made and used to isolate neoepitope-specific T cells. Once isolated, the TCRs and the barcodes were sequenced. Finally, the tumor reactivity of the isolated neoepitope-specific TCRs (neoTCRs) was assessed upon co-culture of autologous melanoma cell lines from each patient with primary human T cells expressing the neoTCRs generated using a CRISPR-based non-viral gene editing to replace the endogenous TCRs. Results: The tumor mutation burden ranged between 3507 and 177 for patients with response to therapy and 977 to 31 for patients without response to therapy. We screened a median of 172 predicted neoantigen-HLA per patient across their 6 HLA molecules and isolated neoTCRs in all 11 patients. The number of mutations targeted ranged between 13 and 1. We assessed the neoTCR-tumor reactivity in samples from 3 patients with response and 3 patients without response. 39 of the 62 neoTCRs demonstrated specific recognition and cytotoxicity to patient-matched melanoma cell lines. Multiple T cell clonotypes recognized a limited number of mutations in 7 patients with response (median of 41 different neoTCR clonotypes per patient), and the T cell specificities were recurrently detected in the blood and the tumor over time. Samples from 4 patients without response to therapy also demonstrated neoepitope-specific T cell responses in blood and tumor to a similarly restricted number of mutations, but lacked TCR polyclonality (median 6.5 neoTCR clonotypes per patient) and were not recurrently detected in sequential samples. Conclusion: Effective ICB therapy is associated with polyclonal neoepitope-specific T-cell responses in the tumor and blood that recognize a limited number of immunodominant mutations and are recurrently detected over time.

  Study phs003153

• An Advanced Molecular Medicine Case Report of a Rare Human Tumor Using Genomics, Pathomics, and Radiomics

  The associated data of this study is derived from a single female patient with pulmonary sclerosing pneumocytoma (PSP). The aim of this study is to provide the most comprehensive, multi-modality sequencing study of a single case of PSP to-date. To this end, the following sequencing experiments were performed: i) RNA-Seq of the primary tumor and adjacent normal tissues (6 replicates for each tissue type), which was intended to analyze RNA-Seq fusions, gene expression, expression mutations, ii) low-pass DNA whole genome sequencing (WGS) from primary tumor tissue and germline, which was intended to analyze copy number aberrations, and iii) DNA targeted panel sequencing of lung cancer associated genes, using primary tumor tissue and germline from white blood cells, which was intended to analyze somatic mutations. Principal findings: i) the PSP hallmark mutation AKT1 (p.E17K) was detected within both the DNA and RNA, and ii) the TP53 signaling pathway was found to be statistically significant by three different pathway analysis tools of analyzing gene expression and pathway ramifications. Among proteins within the TP53 signaling pathway, the p53 inhibitor encoded by MDM2 was found to be overexpressed (by differential gene expression analysis). The original sequencing data (i.e., FastQ files) from each of the aforementioned samples will be accessible through dbGaP.

  Study phs003154

• Sézary Syndrome Originates from Heavily Mutated Hematopoietic Progenitors

  The pathogenesis of cutaneous T cell lymphoma (CTCL) remains unclear. To study the malignant transformation of CTCL, we collected matched hematopoietic stem cell (HSC) extracts from bone marrow, CD4+CD26- malignant T cells, CD4+CD26+ normal T cells, and CD34+ HSCs from apheresis performed on 4 patients. To establish the baseline for calling true mutations without using hematopoietic cells, we also cultured bone marrow fibroblasts from each patient to use as normal controls. Whole exome sequencing (WES) was performed on all samples for somatic mutation calling. We identified >200 mutations in CD34+ HSCs derived from either bone marrow or apheresis. Previously reported key oncodrivers in Sezary Syndrome were identified in autologous HSCs and malignant peripheral cells, but not in progenitor (bone marrow HSCs) cells. Also, we identified specific mutations shared by autologous HSCs and malignant peripheral cells in every patient. WES data of bone marrow HSCs, apheresis HSCs, CD4+CD26- T cells, CD4+CD26+ T cells, and fibroblasts will be available through dbGaP.

  Study phs003158

• Targeted Long-Read Sequencing of the Ewing Sarcoma 6p25.1 Susceptibility Locus

  Ewing Sarcoma (EwS) is rare but the second most common cancer in children, adolescents and young adults. Recent studies suggest germline variation in or around GGAA microsatellites may interact with fusion oncoprotein binding causing changes in binding affinity and potentially impacting enhancer activity on nearby target genes. This study aims to better understand germline variation around EwS susceptibility regions by performing long-range haplotype sequencing of these regions using PacBio sequencing. Our analysis focused on characterizing variation in GGAA microsatellite length as well as germline variants in or around the microsatellite and their association with EwS risk.

  Study phs003159

• Molecular Subtyping Reveals Immune Alterations Associated with Progression of Bronchial Premalignant Lesions

  Exposure to cigarette smoke creates a field of injury throughout the entire respiratory tract inducing genomic alterations that lead to an "at-risk" airway where lung cancers develop. Lung squamous cell carcinoma (SCC) arises in the epithelial layer of the bronchial airways and is often preceded by the development of premalignant lesions (PMLs). Effective tools to identify and treat premalignant lesions at highest risk of progression to invasive carcinoma are not available. Endobronchial biopsies and brushings were obtained from high-risk subjects undergoing lung cancer screening at approximately 1-year intervals by white light and auto-fluorescence bronchoscopy and computed tomography at the Roswell Park Cancer Institute in Buffalo, NY. Subjects were selected that had biopsies collected in repeat locations via serial bronchoscopies. mRNA sequencing was performed on a discovery cohort (DC) of samples comprising endobronchial biopsies and brushes collected between 2010 and 2012 (n=30 subjects, n=197 biopsies, and n=91 brushings). mRNA sequencing was subsequently performed on a validation cohort (VC) of samples comprising endobronchial biopsies and brushes collected between 2010 and 2015 (n=20 subjects, n=111 biopsies, and n=49 brushings). Data analysis identified four distinct molecular subtypes (Proliferative, Inflammatory, Secretory, and Normal) in the bronchial biopsies that correspond to a spectrum of biological and morphological alterations. The Proliferative subtype was enriched with dysplastic PMLs from current smokers that exhibit up-regulation of metabolic and cell cycle pathways and down-regulation of cilium-associated processes. Molecular subtype classification in the validation cohort biopsies replicated these significant clinical and biological associations. Airway brushes from normal fluorescing areas of the large airway classified as the Proliferative subtype specifically predict the presence of biopsies of this same subtype. Within the Proliferative subtype, genes associated with interferon signaling and antigen processing and presentation were observed to be down-regulated among dysplastic biopsies that persist or progress in the future. Innate and adaptive immune cells were computationally predicted to be depleted in these biopsies and this was confirmed via immunofluorescence staining of adjacent biopsies. These findings provide a proof of concept that molecular biomarkers of endobronchial biopsies can enhance histopathological grading and that immunoprevention strategies are an important future direction in intercepting the progression of PMLs to lung cancer.FASTQ files from the RNA sequencing of these biopsies and brushings will be available via dbGaP.

  Study phs003185

• Temporal Evolution Reveals Bifurcated Lineages in Aggressive Neuroendocrine Small Cell Prostate Cancer Trans-Differentiation

  Trans-differentiation from adenocarcinoma to small cell neuroendocrine (SCN) cancer is an adverse consequence of treatment escape in various cancers, including prostate, lung, and bladder cancers (Balanis and Sheu et al., 2019 Cancer Cell). Expression of dominant negative p53 (TP53DN), myrAkt1, RB1-shRNA, c-Myc, and Bcl2(PARCB forward transformation) using human naïve prostate basal epithelial cells recapitulated both transcriptional and histological characteristics of small cell neuroendocrine prostate cancer (NEPC) (Park et al., 2018 Science). To study the temporal transcriptional landscape during this trans-differentiation process, we conducted a time course study using a PARCB model by integrating multi-omics sequencing, including bulk RNA-sequencing and ATAC-sequencing on samples taken at different time point, as well as single cell RNA sequencing on serial xenograft tumors. We found a common SCN pathway that resulted in two distinct end states defined by mutually exclusive expression of ASCL1 and ASCL2. Further investigation using CUT&RUN sequencing identified TFAP4 as a potential epigenetic regulator of both proteins. Our study reveals temporal and transcriptional changes from prostate adenocarcinoma to NEPC trans-differentiation.

  Study phs003230

• ARST17B2-Q Germline and Somatic Genetic Landscape of Pediatric Rhabdomyosarcoma

  Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children. While these malignancies display aberrant myogenic differentiation, relatively little is known about genetic susceptibility to RMS, or how genetic variants influence subsequent somatic events and may be used in risk stratification strategies. A small percentage of cases are associated with mutations in TP53 (Li-Fraumeni syndrome), HRAS (Costello syndrome), and PTCH1 (nevoid basal cell carcinoma syndrome/Gorlin syndrome), suggesting the genetic origins of childhood RMS. In spite of this, little work has been done to characterize genetic susceptibility to this malignancy. We plan to leverage samples collected as part of D9902 to conduct one of the largest germline genomic studies of RMS. We anticipate that once genetic associations are identified, researchers can use the information to develop better strategies to detect, treat, and prevent childhood RMS.

  Study phs003192

• Comprehensive Omics Analysis of Pediatric Solid Tumors and Establishment of a Repository for Related Biologic Studies (10C0086)

  This study (10-C-0086) collected and analyzed tumor and circulating tumor omics of pediatric and young adult patients with relapsed rhabdomyosarcoma who were co-enrolled in and receiving treatment on the interventional study 17-C-0049. We sought to describe the summary genomic findings of tumors, and report on the detection of circulating tumor DNA (ctDNA) in serial samples. Tumor tissue and blood were collected and analyzed. Tumor samples were subjected to whole exome and/or whole genome sequencing paired with RNA-Seq. Cell free DNA (cfDNA) was extracted from serially collected blood samples and sequenced. Fusion status, mutations, and IGF1R and YES1 expression from tumor samples revealed the presence of a PAX3 fusion in most samples, a number of common mutations, and universal but heterogeneous expression of IGF-1R and YES1. ctDNA was detected above the 3% threshold in a majority of patients and analysis of cfDNA demonstrated an ability to monitor tumor clonal evolution.

  Study phs003243

• Structurally Complex Osteosarcoma Genomes Exhibit Limited Heterogeneity within Individual Tumors and across Evolutionary Time

  A key characteristic of osteosarcoma is extensive and complex genomic rearrangements. However, published models explaining how these genomic rearrangements occur disagree about if these rearrangements occur early in tumor progression and then are stable afterwards, or if there is ongoing genomic instability. Previous studies have employed bulk sequencing technologies to characterize genomic alterations. A limitation of this approach is that it averages all changes within the bulk sample, essentially masking intra-sample heterogeneity and making evaluation of ongoing genomic instability difficult. To overcome this limitation and compliment previous work, we utilized single-cell whole genome sequencing to quantify somatic copy number alterations (SCNA). By interrogating individual cells within a sample, we were able to examine intra-sample heterogeneity. We found that the SCNA patterns between cells within a single sample were remarkably consistent, which supports the concept that the genomes of osteosarcoma tumors are relatively stable after early genome fragmentation events.

  Study phs003209

• Melbourne Collaborative Cohort Study DNA Methylation Studies

  This dataset contains raw Illumina 450K blood DNA methylation data from a subset of participants in the Melbourne Cohort Study (MCCS), a prospective study of 41,513 healthy adult volunteers (24,469 women) aged between 27 and 76 years when recruited between 1990 and 1994. Nested case-control studies: DNA methylation data were generated as part of cancer case-control studies nested in the MCCS. Participants were cancer-free at blood draw; blood samples were taken at baseline (1990-1994) for 97% of participants; and for 3% of participants at the second wave of follow-up (2003-2007). Eight separate studies were conducted of breast, prostate, colorectal, lung, kidney, urothelial and gastric cancer and B-cell lymphoma, for a total of > 3,500 cancer cases. Controls were individually matched to cases on age, sex, and country of birth using incidence density sampling. Additional matching on smoking history was made for the study of lung cancer. Longitudinal study: For a subset of 1,100 participants with baseline DNA methylation measures (from dried blood spots) who were selected as controls in the nested case-control studies, repeated methylation measures were made using wave 2 follow-up samples (also from dried blood spots) to study longitudinal DNA methylation changes. Project aims: 1. Nested case-control studies: To assess prospective associations between peripheral blood DNA methylation and risk of eight cancer types (breast, prostate, colorectal, lung, kidney, urothelial cell and gastric cancer, and mature B-cell neoplasms). 2. Longitudinal study: To assess associations between lifestyle changes and changes in peripheral blood DNA methylation.

  Study phs003213

• Molecular Determinants of Esophageal Cancer in Tanzania

  We describe the genomic profiles of 61 esophageal squamous cell carcinoma (ESCC) cases from Tanzania and compare them to profiles from an existing cohort of ESCC cases from Malawi. We also provide a comparison to ESCC tumors in The Cancer Genome Atlas Program (TCGA). Despite a high burden of ESCC in Eastern Africa, investigations into the genomics in this region are nascent. This represents the largest comprehensive genomic analysis of ESCC from sub-Saharan Africa to date. We observed substantial transcriptional overlap with other squamous histologies via comparison with TCGA PanCan dataset. DNA analysis revealed known mutational patterns, both genome-wide as well as in genes known to be commonly mutated in ESCC. TP53 mutations were the most common somatic mutation in tumors from both Tanzania and Malawi but were detected at lower frequencies than previously reported in ESCC cases from other settings. In a combined analysis, two unique transcriptional clusters were identified: a proliferative/epithelial cluster and an invasive/migrative/mesenchymal cluster. Mutational signature analysis of the Tanzanian cohort revealed common signatures associated with aging and cytidine deaminase activity and an absence of signature 29, which was previously reported in the Malawi cohort.

  Study phs003217

• TREM2+ Cells in Human Basal Cell Carcinomas

  To explore the tumor immune microenvironment heterogeneity in sporadic human basal cell carcinoma tumors, we profiled two individual patient tumors by scRNA-Seq. We identified a population of TREM2+ macrophages, which have been implicated in promoting an immunosuppressive tumor microenvironment. We identify that TREM2+ can promote tumor epithelial proliferation in an immunosuppressive independent manner.

  Study phs003242

• Genetic Analysis of Skin Cells

  Cutaneous squamous cell carcinoma (cSCC) is a form of skin cancer originating from keratinocytes in the skin. They have high mutation burdens, primarily driven by UV-radiation-induced DNA damage. The order in which mutations undergo selection during the evolution of cSCC is not known. A subset of cSCCs grow out of benign neoplasms called actinic keratoses. To better understand the evolution of cSCC, we identified cases of cSCCs adjacent to actinic keratoses. From these cases, we separately microdissected the surrounding normal skin, the actinic keratosis, and the cSCC, and we performed targeted DNA-sequencing on the tissue from each area. We reconstructed tumor phylogenies and performed spatial transcriptomics on the 10X FFPE Visium platform on a subset of cases. Collectively, these studies revealed the mutational and gene expression changes that arise during the evolution of cSCC.

  Study phs003282

• Maintenance of Brain Tumor Profile on Organotypic Brain Slice Culture (OBSC)

  We used uncultured tumor resection tissue from an NF2 mutation-driven grade II meningioma (MG-II) to investigate whether tumors engrafted onto organotypic brain slice cultures (OBSCs) maintained the genetic profile of the parent tumor. We prepared three groups of samples for whole exome sequencing (WES) from the same pool of dissociated MG-II tissue. Group HT is the original uncultured human tumor tissue (n = 3). Group CL is the parent tumor tissue expanded in standard in vitro cell culture until the minimum number of cells required for WES had grown. Because of initial cell loss and subsequent clonal expansion, this required six passages over the span of approximately one month (n = 3). Group BSHT is the uncultured tumor resection tissue engrafted onto OBSCs and subsequently dissected from the OBSCs at the conclusion of our standardized assay length (4 days; n = 4). WES analysis showed that tumor tissue engrafted onto OBSCs maintained a significant genetic resemblance to the parent tumor, while tumor tissue expanded in vitro displayed a distinctly different profile. Furthermore, the mutational profiles of all four BSHT biological replicates were markedly similar, indicating that each OBSC-engrafted tumor indeed contained a representative sample of the original patient tumor. A closer look at the hallmark NF2 mutations existing within all samples revealed that while all samples from the original tumor (HT1-3) and the OBSC-engrafted tumor (BSHT1-4) maintain the frame shift deletion at V24, this mutation was lost in all samples expanded in vitro (CL1-3) and replaced by mutations in other areas. Together, this data suggests that the rapid assay design and tumor-accommodating niche of our OBSC platform enables effective maintenance of the original patient tumor profile. The BBsplit algorithm from the BBtools suite was run on all samples to eliminate rat DNA contamination in the BSHT samples as well as to account for any biases that may result as a part of that process. Only the reads that were binned to the human reference were used for subsequent analysis. Reads were then mapped to the GRCh38 version of the human genome with BWA v0.7.17 and realigned together with ABRA2 v.23. Quality control was implemented using the GATK/Picard v4.1.7.0 toolkit. Somatic variants were called for each sample using the MuTect2 algorithm v4.1.7.0. Variants were merged into a single cohort variant call file and then converted to MAF via vcf2maf v1.6.21 tool. Variants were annotated using VEP v87. To identify mutations with potentially high biological impact, multiple filtering steps were applied to somatic mutation calling. First, we selected only the somatic variants that passed all filters from the MuTect2 FilterMutectCalls algorithm and second, only high/moderate impact (change coding) variants as defined by the VEP annotation were further analyzed. Over 1900 single nucleotide variants (SNVs) were detected across all samples. Figures that summarized the results were generated using maftools.

  Study phs003268

• Supraphysiologic MDM2 Expression Impacts P53-Independent Chromatin Networks and Therapeutic Responses in Sarcoma

  We collected multiple liposarcoma samples from different patients, including different subtypes (DD, WD) and normal adipose tissue as control. This study provides the biggest liposarcoma cohort to date, and examined the molecular regulatory circuits associated with MDM2 overexpression. To this end, we obtained not only RNA-seq data, but also ChIP-seq from Jun, RUNX, MDM2, P53 and H3K27ac, as well as hiChIP from tumor samples and cell lines. We found that MDM2 binds to thousands of genes involved in cellular growth and stress response in a P53-independent manner. Furthermore, we described these active genes engaged in multi-way topological interactions that resemble transcriptional hubs.

  Study phs003272