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Am J Hum Genet ; 107(4): 622-635, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32946763


Quantifying the functional effects of complex disease risk variants can provide insights into mechanisms underlying disease biology. Genome-wide association studies have identified 39 regions associated with risk of epithelial ovarian cancer (EOC). The vast majority of these variants lie in the non-coding genome, where they likely function through interaction with gene regulatory elements. In this study we first estimated the heritability explained by known common low penetrance risk alleles for EOC. The narrow sense heritability (hg2) of EOC overall and high-grade serous ovarian cancer (HGSOCs) were estimated to be 5%-6%. Partitioned SNP heritability across broad functional categories indicated a significant contribution of regulatory elements to EOC heritability. We collated epigenomic profiling data for 77 cell and tissue types from Roadmap Epigenomics and ENCODE, and from H3K27Ac ChIP-seq data generated in 26 ovarian cancer and precursor-related cell and tissue types. We identified significant enrichment of risk single-nucleotide polymorphisms (SNPs) in active regulatory elements marked by H3K27Ac in HGSOCs. To further investigate how risk SNPs in active regulatory elements influence predisposition to ovarian cancer, we used motifbreakR to predict the disruption of transcription factor binding sites. We identified 469 candidate causal risk variants in H3K27Ac peaks that are predicted to significantly break transcription factor (TF) motifs. The most frequently broken motif was REST (p value = 0.0028), which has been reported as both a tumor suppressor and an oncogene. Overall, these systematic functional annotations with epigenomic data improve interpretation of EOC risk variants and shed light on likely cells of origin.

Carcinoma Epitelial do Ovário/genética , Proteínas Correpressoras/genética , Cistadenocarcinoma Seroso/genética , Elementos Facilitadores Genéticos , Histonas/genética , Proteínas do Tecido Nervoso/genética , Neoplasias Ovarianas/genética , Alelos , Sítios de Ligação , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/patologia , Mapeamento Cromossômico , Proteínas Correpressoras/metabolismo , Cistadenocarcinoma Seroso/diagnóstico , Cistadenocarcinoma Seroso/patologia , Feminino , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Histonas/metabolismo , Humanos , Padrões de Herança , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia , Penetrância , Polimorfismo de Nucleotídeo Único , Risco
Cell Rep ; 29(11): 3726-3735.e4, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31825847


Fallopian tube secretory epithelial cells (FTSECs) are likely the main precursor cell type of high-grade serous ovarian cancers (HGSOCs), but these tumors may also arise from ovarian surface epithelial cells (OSECs). We profiled global landscapes of gene expression and active chromatin to characterize molecular similarities between OSECs (n = 114), FTSECs (n = 74), and HGSOCs (n = 394). A one-class machine learning algorithm predicts that most HGSOCs derive from FTSECs, with particularly high FTSEC scores in mesenchymal-type HGSOCs (padj < 8 × 10-4). However, a subset of HGSOCs likely derive from OSECs, particularly HGSOCs of the proliferative type (padj < 2 × 10-4), suggesting a dualistic model for HGSOC origins. Super-enhancer (SE) landscapes were also more similar between FTSECs and HGSOCs than between OSECs and HGSOCs (p < 2.2 × 10-16). The SOX18 transcription factor (TF) coincided with a HGSOC-specific SE, and ectopic overexpression of SOX18 in FTSECs caused epithelial-to-mesenchymal transition, indicating that SOX18 plays a role in establishing the mesenchymal signature of fallopian-derived HGSOCs.

Neoplasias Ovarianas/genética , Fatores de Transcrição SOXF/genética , Adulto , Idoso , Linhagem Celular , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Tubas Uterinas/metabolismo , Tubas Uterinas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Aprendizado de Máquina , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Ovário/metabolismo , Ovário/patologia , RNA-Seq , Fatores de Transcrição SOXF/metabolismo , Análise de Célula Única , Transcriptoma
iScience ; 17: 242-255, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31307004


Long noncoding RNAs (lncRNAs) have emerged as critical regulators of tumorigenesis, and yet their mechanistic roles remain challenging to characterize. Here, we integrate functional proteomics with lncRNA-interactome profiling to characterize Urothelial Cancer Associated 1 (UCA1), a candidate driver of ovarian cancer development. Reverse phase protein array (RPPA) analysis indicates that UCA1 activates transcription coactivator YAP and its target genes. In vivo RNA antisense purification (iRAP) of UCA1 interacting proteins identified angiomotin (AMOT), a known YAP regulator, as a direct binding partner. Loss-of-function experiments show that AMOT mediates YAP activation by UCA1, as UCA1 enhances the AMOT-YAP interaction to promote YAP dephosphorylation and nuclear translocation. Together, we characterize UCA1 as a lncRNA regulator of Hippo-YAP signaling and highlight the UCA1-AMOT-YAP signaling axis in ovarian cancer development.

PLoS One ; 13(5): e0196913, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29738525


Exosomes are endosome-derived membrane vesicles that contain proteins, lipids, and nucleic acids. The exosomal transcriptome mediates intercellular communication, and represents an understudied reservoir of novel biomarkers for human diseases. Next-generation sequencing enables complex quantitative characterization of exosomal RNAs from diverse sources. However, detailed protocols describing exosome purification for preparation of exosomal RNA-sequence (RNA-Seq) libraries are lacking. Here we compared methods for isolation of exosomes and extraction of exosomal RNA from human cell-free serum, as well as strategies for attaining equal representation of samples within pooled RNA-Seq libraries. We compared commercial precipitation with ultracentrifugation for exosome purification and confirmed the presence of exosomes via both transmission electron microscopy and immunoblotting. Exosomal RNA extraction was compared using four different RNA purification methods. We determined the minimal starting volume of serum required for exosome preparation and showed that high quality exosomal RNA can be isolated from sera stored for over a decade. Finally, RNA-Seq libraries were successfully prepared with exosomal RNAs extracted from human cell-free serum, cataloguing both coding and non-coding exosomal transcripts. This method provides researchers with strategic options to prepare RNA-Seq libraries and compare RNA-Seq data quantitatively from minimal volumes of fresh and archival human cell-free serum for disease biomarker discovery.

Ácidos Nucleicos Livres/sangue , Exossomos/genética , Análise de Sequência de RNA/métodos , Transcriptoma/genética , Biomarcadores/sangue , Ácidos Nucleicos Livres/genética , Humanos , Manejo de Espécimes