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• Genes associated with pancreas development and function maintain open chromatin in iPSCs generated from human pancreatic beta cells

  Current in-vitro islet differentiation protocols suffer from heterogeneity and low efficiency. Induced-pluripotent stem cells (iPSCs) derived from pancreatic beta-cells (BiPSCs) preferentially differentiate towards endocrine pancreas-like cells versus those from fibroblasts (FiPSCs). We interrogated genome-wide open chromatin in BiPSCs and FiPSCs via ATAC-seq, and identified ~8.3k significant, differential open chromatin sites (DOCS) between the two iPSC subtypes (FDR<0.05). DOCS where chromatin was more accessible in BiPSCs (Bi-DOCS) were significantly enriched for known regulators of endodermal development, including bivalent and weak enhancers, and FOXA2 binding sites (FDR<0.05). Bi-DOCS were associated with genes related to pancreas development and beta-cell function, including transcription factors mutated in monogenic diabetes (PDX1, NKX2-2, HNF1A; FDR<0.05). Moreover, Bi-DOCS correlated with enhanced gene expression in BiPSC-derived definitive endoderm and pancreatic progenitor cells. Bi-DOCS therefore highlight genes and pathways governing islet-lineage commitment, which can be exploited for differentiation protocol optimisation, diabetes disease modelling, and therapeutic purposes.

  Study EGAS00001002591

• Single-nuclei gene-expression analysis of pheochromocytoma and paraganglioma links tumor subtypes with tumor microenvironment

  Pheochromocytomas and paragangliomas (PCPG) are rare neuroendocrine tumors associated with autonomic nerves. We used single nuclei-RNA-seq (snRNA-seq) for analysis of 30 PCPG representing 13 known driver genes, plus two normal adrenal medullas to dissect cell composition, refine PCPG subtypes and compare PCPG and normal tissue expression. Incorporating bulk-tissue and snRNA-seq data we identified seven PCPG gene-expression subtypes with genotype and cell type associations. The tumor microenvironment reflected HIF pathway activation and neovascularization by detection of abundant tip-like endothelial cells and pericytes concordant with VEGFA expression in neoplastic cells with mutations in VHL, genes encoding SDH subunits and MAML3-fusions. Macrophages were abundant in PCPG with distinct tumor-associated features. Schwann-cell-like cells were also enriched in some subtypes. The transcriptional profile of neoplastic PCPG cells resembled normal chromaffin cells but early chromaffin and neuroblast cell markers were expressed in some subtypes including GPR139, a putative therapeutic target for a subset of pseudohypoxic PCPG.

  Study EGAS00001005861

• The miR-185/PAK6 Axis Predicts Therapy Response and Regulates Survival of Drug-Resistant Leukemic Stem Cells in Chronic Myeloid Leukemia

  Overcoming drug resistance and targeting cancer stem cells remain challenges for curative cancer treatment. To investigate the role of miRNAs in regulating drug resistance and leukemic stem cell (LSCs) fate, we performed global transcriptome profiling in treatment-naïve chronic myeloid leukemia (CML) stem/progenitor cells and identified that miR-185 levels anticipate their response to ABL tyrosine kinase inhibitors (TKIs). miR-185 functions as a tumor suppressor; its restored expression impaired survival of drug-resistant cells, sensitized them to TKIs in vitro, and markedly eliminated long-term repopulating LSCs and infiltrating blast cells, conferring a survival advantage in pre-clinical xenotransplantation models. Integrative analysis with mRNA profiles uncovered PAK6 as a crucial target of miR-185 and pharmacological inhibition of PAK6 perturbed the RAS/MAPK pathway and mitochondrial activity, sensitizing therapy-resistant cells to TKIs. Thus, miR-185 presents as a potential predictive biomarker, and dual targeting of miR-185-mediated PAK6 activity and BCR-ABL may provide a valuable strategy for overcoming drug resistance in patients.

  Study EGAS00001004153

• The Vaginal Microbiome: Disease, Genetics and the Environment

  The vagina is an interactive interface with the environment, and as such is covered by a protective epithelial surface. This surface is colonized by a biofilm consisting of bacteria and other microorganisms, which through a variety of mechanisms serve to protect the host from invasion by pathogens. Alterations in the normal vaginal microflora; i.e., dysbioses, particularly those associated with bacterial vaginosis, the most common disorder of the female reproductive tract, contribute to risk of sexually transmitted infections, infection by HIV, and are associated with increased risk of adverse pregnancy outcomes including but not limited to spontaneous preterm birth. Physiologic alterations in the host (e.g., menopause and pregnancy), which are beginning to be investigated as potential selective conditions for change in the "normal" vaginal flora, and their impact on disease susceptibility and transmission, remain to be more definitively elucidated. The effects of chronically abnormal physiologic states (e.g., diabetes mellitus) on normal vaginal flora have not been well described or studied. Finally, an almost unexplored area of inquiry is the genetic contribution, including race/ethnicity, to the establishment and maintenance of a "normal" vaginal flora, under normal and physiologically altered circumstances. Our research will shed light on how the vaginal microbiome contributes to adverse obstetrical outcomes and sexually transmitted infections in diverse populations. This project addresses the following questions: First: Do the genes of the host contribute to the composition of the vaginal microbiome? We hypothesize that a woman's genetic composition significantly affects the ability of certain commensal, parasitic and pathogenic microbes to colonize and/or infect the genital tract. Thus, we will compare and quantify the microbial populations inhabiting the vaginas of monozygotic and dizygotic twins from the Mid Atlantic Twin Registry, and, in the process, address the question of whether there is a relationship between the microbiomes of the vagina, mouth and GI tract. Second: What changes in the vaginal microbiome are associated with common physiological perturbations or non-infectious pathological states of the host?We hypothesize that "altered" physiologic (pregnancy, menopause) and pathologic (chronic disease, hysterectomy) conditions, or environmental "exposures" (exogenous hormones, antibiotics, chronic immunosuppressant, smoking; douching) can predictably alter the vaginal microenvironment. These alterations will lead to changes in microbial populations within the vagina. Changes in the microbial populations may have impacts, positive or more likely negative, on the spontaneous and future well-being of the affected individual. We are characterizing the effects of these "altered" physiologic and pathologic conditions, and environmental exposures, on the composition of the vaginal microbiome. Finally, we are examining the impact of the important physiological changes incurred during pregnancy on the composition of the microbiome of the female reproductive tract. Third: What changes in the vaginal microbiome are associated with relevant infectious diseases and conditions? We are testing the hypothesis that infectious diseases predictably alter the vaginal microbiome, and that these changes have an impact on the disease susceptibility, process, and outcome. A predilection for bacterial vaginosis, vaginitis, HIV infection, or other sexually transmitted diseases, is likely associated with a women's vaginal microbial composition. Thus, we will characterize samples from women with a variety of these infectious conditions to determine the contribution of their microbiomes to the disease process and susceptibility. We are addressing these questions using a combination of high throughput 'nextgen' sequencing technologies. Early studies were performed using the Roche 454 FLX and the first generation Illumina Genome Analyzer II instruments and more recently employing Illumina MiSeq and HiSeq 2500 and 4000 platforms, installed in the Genomics Core of the Nucleic Acids Research Facilities at VCU. Thus, segments of the 16S rRNA genes are amplified from the complex samples taken from various target sites in and around the vagina of each study participant. These segments are sequenced and subjected to taxonomic classification protocols to identify and quantify the bacterial taxa present in each sample. Additionally, total DNA isolated from these samples are subjected to shotgun sequence analysis to empirically reconstruct the metabolic potential of these microbiomes. Finally, specific bacterial clones are completely sequenced and analyzed to associate the unavoidable strain and isolate diversity with the clinical phenotypes presented.

  Study phs000256

• Sanger sequencing of catalytic-domain encoding exons of tyrosine kinase genes from human endometrial tumor DNAs

  The purpose of the original study was to search for somatic mutations in the tyrosine kinome of serous and clear cell endometrial carcinomas (human). The study was conducted in two phases. Phase 1: A mutation discovery screen, in which ~577 exons encoding the catalytic domains of 86 tyrosine kinases were PCR-amplified and bidirectionally Sanger sequenced from 24 serous, 11 clear cell, and 5 mixed histology endometrial tumors. This was followed by alignment of sequence reads to the human reference sequence and subsequent nucleotide variant calling to identify potential somatic (tumor-specific) mutations. Potential somatic mutations were confirmed by re-amplification and sequencing of the relevant tumor DNA as well as matched non-tumor ("normal") DNA from the same case. Phase 2: A mutation prevalence screen, in which the non-catalytic regions two tyrosine kinase genes, TNK2 and DDR1, were PCR-amplified and sequenced from the 40 discovery screen tumors, and all coding exons of TNK2 and DDR1 were PCR-amplified and sequenced from another 10 clear cell, 21 serous, and 41 endometrioid endometrial tumors, in an effort to identify additional somatic mutations in each gene. Exons encoding the exonuclease domain of POLE were also sequenced to document somatic mutations.

  Study phs000841

• Multicenter AIDS Cohort Study (MACS)

  The Multicenter AIDS Cohort Study (MACS) - now part of the MACS-WIHS Combined Cohort Study (MWCCS) investigates the epidemiology of human immunodeficiency virus (HIV) infection among men who have sex with men. Over 7,000 participants volunteered for semiannual interview, physical examination, and laboratory testing across the 325 years of the study, in four metropolitan areas of Los Angeles, Chicago, Baltimore/Washington (DC) and Pittsburgh. The study aimed to identify risk factors for occurrence and clinical expression of the HIV infection, and to establish a repository of biologic specimens for future study. Study visits included detailed questions covering HIV-related symptoms and utilization of health services, demographic and psychosocial characteristics, a quality of life survey, a physical examination, a detailed form on medications used as prophylaxis and/or treatment, a neuropsychological screening and examination, blood samples to do measure hematologic variables including enumeration of T-cell subsets and HIV viral load and evaluate genetic risk factors via genome wide association studies using data generated using the Infinium Multi-Ethnic Global BeadChip genotyping array in all participants. Men who have sex with men, with and without HIV infection were enrolled in the MACS. MACS data continues to be available through the merged MWCCS cohort.

  Study phs002226

• Longitudinal Study of Urea Cycle Disorders

  Individuals with Urea Cycle Disorders (UCD) cannot remove ammonia, a waste product, from the blood. The purpose of this study is to conduct a longitudinal investigation of the natural history, morbidity, and mortality in people with UCD. This study will look at how people with a UCD grow and develop over time and how often they get sick. The research questions are: What is the prevalence of specific morbid indicators of disease severity, including hyperammonemia, developmental disabilities, and various long-term kidney and liver effects? What is the fatality rate associated with the various forms of UCD? What are the correlations between various biomarkers and disease severity and progression? What is the safety and efficacy of currently used and new UCD therapies? This is a longitudinal study of individuals with urea cycle disorders. Those participating in this study will be evaluated every three to twelve months, depending age and time of diagnosis. Participants two years of age and younger that were diagnosed with UCD within the first four weeks of life will be evaluated every three months. Those who are over two years of age or were diagnosed after four weeks of age will be evaluated every six months. Participants older than 18 years of age will be evaluated once every year.

  Study phs000577

• Gabriella Miller Kids First Pediatric Research Program for Infantile Hemangiomas Associated with Multi-Organ Structural Birth Defects

  The Gabriella Miller Kids First Pediatric Research Program (Kids First) is a trans-NIH effort initiated in response to the 2014 Gabriella Miller Kids First Research Act and supported by the NIH Common Fund. This program focuses on gene discovery in pediatric cancers and structural birth defects and the development of the Gabriella Miller Kids First Pediatric Data Resource (Kids First Data Resource). All of the WGS and phenotypic data from this study are accessible through dbGaP and kidsfirstdrc.org, where other Kids First datasets can also be accessed. Infantile hemangiomas are the most common benign vascular tumor in infants, affecting 4-5% of children. Thirty percent of segmental infantile hemangiomas on the face and scalp are associated with birth defects of multiple organs. This condition is known as PHACE, an acronym for posterior fossa brain malformations, segmental facial hemangiomas, arterial anomalies, cardiac defects, eye anomalies, and sternal clefting. Genomic analysis of PHACE will inform treatment and expand knowledge about the causes of birth defects affecting the brain, arteries, heart, eye, midline development and hearing. The knowledge gained in this study will be used to drive strategies for prevention and provide critical targets for treatments for a range of birth defects and infantile hemangiomas.

  Study phs001785

• Exploring the Microbiome-Gut-Brain Axis with Respect to Psychoneurological Symptoms for Children with Solid Tumors

  The human body hosts tens of trillions of microbes, a number 10 times greater than the number of human body cells. The collection of these human-associated microbes and their genomes is called the “human microbiome”. More than 90% of these microbes live in the gastrointestinal (GI) tract, representing 500 species on average. With the development of high-throughput sequencing technology and bioinformatics tools (e.g., 16S ribosomal RNA or 16S rRNA sequencing and shotgun metagenomics analysis), recent progress has been made to elaborate the critical role that the gut microbiome plays in human health and disease. A significant disruption (dysbiosis) of the composition and function of the gut microbiome is associated with carcinogenesis, chemotherapeutic metabolism, and treatment-related symptom toxicities. The current state of science on the gut microbiome in cancer has only recently started in animal models and adults, and has not been well investigated in children diagnosed and treated for cancer, nor with respect to associations with cancer treatment-related toxicities. This proposed study will explore the hypothesis that dysbiosis of the gut microbiome is associated with cancer treatment-related GI and psychoneurological symptoms. We will collect both stool samples (for the gut microbiome) and patient-reported outcomes across chemotherapy.

  Study phs002960

• Joint-Specific TF Regulation in RA

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

  Study phs003633