5617 results for "canc*"

in 15.64 milliseconds.

• Lineage Plasticity and Immune Cell Heterogeneity Are Coordinately Dysregulated Through Changes in FOXA1 Expression in Bladder Cancers with Squamous Differentiation

  We performed whole exome sequencing (WES) of paired, macrodissected regions of urothelial carcinoma (UC), not otherwise specified (NOS-UC) and squamous differentiation (SqD) from 21 bladder tumors in which distinct and separable NOS-UC and SqD regions were present (total 42 exomes, in addition to matched normal exomes). Mean tumor mutational burden (TMB) was higher in the SqD versus the NOS-UC regions. Consistent with the higher TMB, the SqD regions also had a higher neoantigen burden than the patient-matched NOS-UC regions. The SqD regions also exhibited higher karyotypic complexity with a higher median ploidy relative to the paired NOS-UC regions. Phylogenetic analysis of the WES data confirmed that the morphologically distinct regions of all 21 tumors arose from a shared precursor with a median of 68 (range 16 – 852) non-synonymous mutations shared between the NOS-UC and SqD regions, and the overall data were indicative of early branched evolution. As whole exome sequencing did not identify a shared mutational alteration or genomic signature unique to the SqD or NOS-UC components, we therefore performed expression profiling of separable SqD and NOS-UC regions of 12 bladder tumors from the WES cohort with RNA quality sufficient for whole transcriptome RNA-sequencing (RNAseq, total of 24 regions). Based on centroid clustering analysis of expression data, all 12 regions of SqD were basal-squamous subtype based on the TCGA molecular classification schema. Notably, 8 of the NOS-UC regions were also basal-squamous subtype, with only four pairs exhibiting discordant transcriptional subtypes (three NOS-UC regions were luminal-infiltrated, one luminal-papillary). To better quantify differences in the transcriptional profiles of the paired NOS-UC and SqD regions, we used single sample gene set enrichment analysis (ssGSEA) to assess for enrichment of luminal or basal-squamous gene expression. ssGSEA analysis revealed that the SqD regions expressed higher levels of basal-squamous genes based on the BASE47 gene set and UPK/KRT gene sets; whereas the matched NOS-UC regions expressed higher levels of luminal genes. These differences in the levels of expression of basal and luminal genes were observed even in cases in which both the NOS-UC and SqD regions were basal-squamous subtype based the TCGA molecular classification schema. Exomes from eight patients in this study have previously been deposited in dbGaP: accession number phs001783 as part of the study "Exome Recapture and Sequencing of Prospectively Characterized Clinical Specimens From Cancer Patients".

  Study phs002357

• Human Tumor Atlas Network (HTAN)

  An NCI-funded Cancer Moonshot initiative to construct 3-dimensional atlases of the dynamic cellular, morphological, and molecular features of human cancers as they evolve from precancerous lesions to advanced disease.

  Study phs002371

• Characterizing TP53 and PPM1D Mutations as Resistance Drivers to Radiation Therapy in Diffuse Intrinsic Pontine Gliomas

  Pediatric high-grade gliomas (pHGGs), encompassing diffuse midline gliomas (DMGs) and hemispheric tumors, represent the most common cause of cancer-related deaths in children age 0-14 years. Over the last decade, several landmark papers have revealed recurrent single nucleotide variants (SNVs) in the core histones H3.3 and H3.1, co-occurring with alterations in the TP53 signaling pathway and receptor tyrosine kinases (RTKs). However, the contribution of structural variants (SVs) to gliomagenesis has not been systematically explored. We performed a comprehensive analysis of whole genome sequencing (WGS) data on pediatric high-grade gliomas (pHGGs) from 179 children, including 61 hemispheric tumors and 118 diffuse midline gliomas, or DMGs, of which 61 are novel to this study. Among the DMGs, 84 (71%) were from pre-treatment biopsies including 33 obtained from the first multi-institutional North American clinical trial to incorporate diagnostic biopsies. This represents the largest cohort of pretreatment DMGs with whole genome sequencing to date. This large cohort of whole genome sequences provides an unparalleled opportunity to assess significantly recurrent structural variants in pHGG and their associations with driver SNVs and SCNAs. 

  Study phs002380

• Ghana Breast Health Study

  The Ghana Breast Health Study (GBHS) was a multi-disciplinary, population-based case-control study conducted in Accra and Kumasi, Ghana that was designed to investigate breast cancer etiology in the West Africa region. The study enrolled 1,126 invasive breast cancer cases and 2,106 frequency matched population-based controls using census-based sampling. GHBS participants were between the ages of 18 to 74 years of age. Breast cancer cases were recruited at the time they presented with lesions suspicious of breast cancer at three hospitals: Korle Bu Teaching Hospital (Accra), Komfo Anoyke Teaching Hospital (Kumasi) and Peace and Love Hospital (Kumasi). These hospitals are the primary providers of treatment for breast cancer in Ghana, allowing for cases in our study to represent most breast cancers diagnosed in these areas during the study period. The following publications describe the GBHS in detail: 1) Brinton LA et al. Design considerations for identifying breast cancer risk factors in a population-based study in Africa. Int J Cancer 2017;140:2667-2677 (PMID:28295287). 2) Nyante SJ et al. Recruiting population controls for case-control studies in sub-Saharan Africa: The Ghana Breast Health Study. PloS one 2019;14:e0215347 (PMID:30990841)Among subjects with an available source of germline DNA genotyping was performed using the Infinium Global Screening Array-24 per the manufacturer’s guidelines using the Infinium automated protocol. We excluded probable duplicates and close relatives, and samples with a call rate < 95% or samples with extreme heterozygosity. Female sex was verified by Identifiler using X chromosome heterozygosity and the X chromosome inbreeding coefficient F statistics. The GLU genetics’ ld.tagzilla module was used to confirm African ancestry. To resolve more detailed population substructure, principal components analysis was conducted among all unrelated subjects using the EIGENSOFT v7.2.1. Imputation was performed using the Michigan imputation server Minimac3 with 1K genomes phase3 as reference panel.

  Study phs002387

• Integrated Metabolic Profiling and Gene Expression Analysis Reveals Therapeutic Modalities in Breast Cancer

  In this study, we performed metabolite profiling and RNA-sequencing on human breast cancer tumors and normal breast tissue samples, including triple negative breast cancer (TNBC), estrogen receptor positive breast cancer (ER+) and paired normal samples, and patient-derived xenografts (PDX) samples. Here, we report two distinctive groups defined by metabolites; a TNBC-HIGH group that shows high levels of pyrimidine pathway metabolites and biosynthetic enzymes, and an ER-HIGH group that shows high levels of fatty acid and arginine biosynthesis intermediates. We identify different metabolic enrichment profiles between cell lines grown in vitro vs. in vivo; cell lines grown in vivo recapitulate patient tumors metabolic profiles. Further, we identify a subset of genes that strongly correlates with the TNBC-HIGH metabolic profile using integrated metabolic and gene expression profiling, which strongly predicts patient prognosis when tested on larger human datasets. As a proof-of-principle, when we target TNBC-HIGH metabolic dysregulation with a pyrimidine biosynthesis inhibitor (Brequinar), and/or a glutaminase inhibitor (CB-839), we observe therapeutic efficacy and decreased tumor growth in representative TNBC cell lines, murine p53-null mammary tumors, and in vivo patient-derived xenografts (PDXs) upon multi-agent drug treatment. This study highlights potential new therapeutic opportunities in breast cancers guided by a genomic biomarker, which could prove impactful for breast cancers that rapidly proliferate.

  Study phs002396

• Genomics of Prostate Cancer

  This dataset includes genomic data from patients with prostate cancer. Specimens include archival active surveillance biopsies, radical prostatectomy specimens selected based on evidence of PD-L1 expression and/or T lymphocyte infiltrates, and rapid autopsy material from patients deceased of prostate cancer. These data include low pass whole genome sequencing and targeted sequencing with matched normal.

  Study phs002398

• A Single Cell Atlas of MMRd and MMRp Colorectal Cancer

  Immune responses to cancer vary across cancer types and patients. Colorectal cancer tumors with mismatch repair-deficiency (MMRd) show an elevated immune cell activity as compared to mismatch repair proficient (MMRp) tumors. To understand the immune response patterns in these two types of colorectal cancer, we transcriptionally profiled 371,223 tumor and adjacent normal cells from 28 MMRp and 34 MMRd patients. Unsupervised analysis identified 88 cell subsets, from 7 distinct cell clusters (that contain epithelial, malignant, stromal and immune cell lineages), and an associated compendium of 204 gene expression programs. Examination of these cell subsets and programs revealed extensive transcriptional and spatial remodeling of malignant, stromal and immune cells in MMRd and MMRp tumors. This dataset was generated as part of a published study (Pelka, Hofree, Chen, et al., Cell 2021 Sep 2;184(18):4734-4752; PMID: 34450029).

  Study phs002407

• Genome Instability in Mammary Cells of Pathogenic BRCA1/2 Mutation Carriers

  It remains unknown if inherited germline mutations in the BRCA1 or BRCA2 gene increase the risk of breast and ovarian cancer by elevating mutation rate in mammary cells. Here we show, using a single-cell whole genome sequencing approach, that mammary luminal epithelial cells isolated from tissues obtained from preventive mastectomy surgeries in women with a pathogenic BRCA1/2 germline mutation, exhibit a statistically significant, increased mutation frequency as compared to age-matched controls without genetic risk of breast cancer.

  Study phs002411

• Integrative Molecular Characterization of Breast Cancer

  We have performed integrative analyses of breast cancer tumors, including whole exome sequencing of tumor & normal pairs, whole transcriptome sequencing, and single-cell/nucleus RNA sequencing, to determine molecular correlates of response to novel and immune therapies. We have focused on dissecting the role of anticancer immunity in response to these therapies and understanding biological mechanisms underlying therapeutic resistance. The goal of this work is to advance a precision medicine approach to breast cancer treatment by identifying molecular biomarkers to improve therapy selection and novel therapeutic targets to overcome resistance. 

  Study phs002419

• Tandem DNA Repeats Activate hTERT Gene Transcription

  Multiple independent sequence variants of the hTERT locus have been associated with telomere length and cancer risks in genome-wide association studies. Here, we identified an intronic variable number tandem repeat, VNTR2-1, as an enhancer-like element, which activated hTERT transcription in a cell and chromatin-dependent manner. VNTR2-1, consisting of 42-bp repeats with an array of E-boxes, cooperated with the proximal promoter in hTERT regulation by bHLH transcription factors and maintained hTERT expression during embryonic stem cell differentiation. Genomic deletion of VNTR2-1 in MelJuSo melanoma cells markedly reduced hTERT transcription, leading to telomere shortening, cellular senescence, and impairment of xenograft tumor growth. Interestingly, VNTR2-1 lengths varied widely in human populations.  To assess the genetic polymorphism of VNTR2-1 in human populations, we analyzed genomic DNA samples of Caucasian Americans and African Americans enrolled in the Georgia Centenarian Study.  VNTR2-1 in these genomic DNA samples were PCR amplified and subjected to sequencing analysis usinb the PacBio® SMRT method. The result showed that all VNTR2-1 alleles in Caucasian Americans contained 76 or more 42-bp repeats, whereas 32% of VNTR2-1 alleles in African Americans had fewer than 76 repeats.  

  Study phs002428