RESUMO
ZCCHC17 is a putative master regulator of synaptic gene dysfunction in Alzheimer's disease (AD), and ZCCHC17 protein declines early in AD brain tissue, before significant gliosis or neuronal loss. Here, we investigate the function of ZCCHC17 and its role in AD pathogenesis using data from human autopsy tissue (consisting of males and females) and female human cell lines. Co-immunoprecipitation (co-IP) of ZCCHC17 followed by mass spectrometry analysis in human iPSC-derived neurons reveals that ZCCHC17's binding partners are enriched for RNA-splicing proteins. ZCCHC17 knockdown results in widespread RNA-splicing changes that significantly overlap with splicing changes found in AD brain tissue, with synaptic genes commonly affected. ZCCHC17 expression correlates with cognitive resilience in AD patients, and we uncover an APOE4-dependent negative correlation of ZCCHC17 expression with tangle burden. Furthermore, a majority of ZCCHC17 interactors also co-IP with known tau interactors, and we find a significant overlap between alternatively spliced genes in ZCCHC17 knockdown and tau overexpression neurons. These results demonstrate ZCCHC17's role in neuronal RNA processing and its interaction with pathology and cognitive resilience in AD, and suggest that the maintenance of ZCCHC17 function may be a therapeutic strategy for preserving cognitive function in the setting of AD pathology.
Assuntos
Doença de Alzheimer , Resiliência Psicológica , Feminino , Humanos , Masculino , Doença de Alzheimer/metabolismo , Cognição , Neurônios/metabolismo , RNA , Splicing de RNA/genética , Proteínas tau/metabolismoRESUMO
ZCCHC17 is a putative master regulator of synaptic gene dysfunction in Alzheimer's Disease (AD), and ZCCHC17 protein declines early in AD brain tissue, before significant gliosis or neuronal loss. Here, we investigate the function of ZCCHC17 and its role in AD pathogenesis. Co-immunoprecipitation of ZCCHC17 followed by mass spectrometry analysis in human iPSC-derived neurons reveals that ZCCHC17's binding partners are enriched for RNA splicing proteins. ZCCHC17 knockdown results in widespread RNA splicing changes that significantly overlap with splicing changes found in AD brain tissue, with synaptic genes commonly affected. ZCCHC17 expression correlates with cognitive resilience in AD patients, and we uncover an APOE4 dependent negative correlation of ZCCHC17 expression with tangle burden. Furthermore, a majority of ZCCHC17 interactors also co-IP with known tau interactors, and we find significant overlap between alternatively spliced genes in ZCCHC17 knockdown and tau overexpression neurons. These results demonstrate ZCCHC17's role in neuronal RNA processing and its interaction with pathology and cognitive resilience in AD, and suggest that maintenance of ZCCHC17 function may be a therapeutic strategy for preserving cognitive function in the setting of AD pathology.
RESUMO
BACKGROUND: Increased breast cancer screening over the past four decades has led to a substantial rise in the diagnosis of ductal carcinoma in situ (DCIS). Although DCIS lesions precede invasive ductal carcinoma (IDC), they do not always transform into cancer. The current standard-of-care for DCIS is an aggressive course of therapy to prevent invasive and metastatic disease resulting in over-diagnosis and over-treatment. Thus, there is a critical need to identify functional determinants of progression of DCIS to IDC to allow discrimination between indolent and aggressive disease. Recent studies show that super-enhancers, in addition to promoting other gene transcription, are themselves transcribed producing super-enhancer associated long noncoding RNAs (SE-lncRNAs). These SE-lncRNAs can interact with their associated enhancer regions in cis and influence activities and expression of neighboring genes. Furthermore, they represent a novel, untapped group of therapeutic targets. METHODS: With an integrative analysis of enhancer loci with global expression of SE-lncRNAs in the MCF10A progression series, we have identified differentially expressed SE-lncRNAs which can identify mechanisms for DCIS to IDC progression. Furthermore, cross-referencing these SE-lncRNAs with patient samples in the The Cancer Genome Atlas (TCGA) database, we have unveiled 27 clinically relevant SE-lncRNAs that potentially interact with their enhancer to regulate nearby gene expression. To complement SE-lncRNA expression studies, we conducted an unbiased global analysis of super-enhancers that are acquired or lost in progression. RESULTS: Here we designate SE-lncRNAs RP11-379F4.4 and RP11-465B22.8 as potential markers of progression of DCIS to IDC through regulation of the expression of their neighboring genes (RARRES1 and miR-200b, respectively). Moreover, we classified 403 super-enhancer regions in MCF10A normal cells, 627 in AT1, 1053 in DCIS, and 320 in CA1 cells. Comparison analysis of acquired/lost super-enhancer regions with super-enhancer regions classified in 47 ER positive patients, 10 triple negative breast cancer (TNBC) patients, and 11 TNBC cell lines reveal critically acquired pathways including STAT signaling and NF-kB signaling. In contrast, protein folding, and local estrogen production are identified as major pathways lost in progression. CONCLUSION: Collectively, these analyses identify differentially expressed SE-lncRNAs and acquired/lost super-enhancers in progression of breast cancer important for promoting DCIS lesions to IDC.
Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Elementos Facilitadores Genéticos/genética , RNA Longo não Codificante/genética , Biomarcadores Tumorais/genética , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Linhagem Celular , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Membrana/genética , MicroRNAs/genética , Receptores de Estrogênio/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
The purpose of this review is to highlight several areas of lncRNA biology and cancer that we hope will provide some new insights for future research. These include the relationship of lncRNAs and the epithelial to mesenchymal transition (EMT) with a focus on transcriptional and alternative splicing mechanisms and mRNA stability through miRNAs. In addition, we highlight the potential role of enhancer e-lncRNAs, the importance of transposable elements in lncRNA biology, and finally the emerging area of using antisense oligonucleotides (ASOs) and small molecules to target lncRNAs and their therapeutic implications.
Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , RNA Longo não Codificante/genética , Animais , Movimento Celular/genética , Elementos de DNA Transponíveis , Suscetibilidade a Doenças , Elementos Facilitadores Genéticos , Transição Epitelial-Mesenquimal/genética , Humanos , MicroRNAs/genética , Neoplasias/metabolismo , Neoplasias/patologia , Ligação Proteica , Processamento Pós-Transcricional do RNA , Splicing de RNA , Estabilidade de RNA , RNA Mensageiro/genética , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
Ductal carcinoma in situ (DCIS) is a nonobligate precursor to invasive breast cancer. Only a small percentage of DCIS cases are predicted to progress; however, there is no method to determine which DCIS lesions will remain innocuous from those that will become invasive disease. Therefore, DCIS is treated aggressively creating a current state of overdiagnosis and overtreatment. There is a critical need to identify functional determinants of progression of DCIS to invasive ductal carcinoma (IDC). Interrogating biopsies from five patients with contiguous DCIS and IDC lesions, we have shown that expression of the long noncoding RNA BHLHE40-AS1 increases with disease progression. BHLHE40-AS1 expression supports DCIS cell proliferation, motility, and invasive potential. Mechanistically, BHLHE40-AS1 modulates interleukin (IL)-6/signal transducer and activator of transcription 3 (STAT3) activity and a proinflammatory cytokine signature, in part through interaction with interleukin enhancer-binding factor 3. These data suggest that BHLHE40-AS1 supports early breast cancer progression by engaging STAT3 signaling, creating an immune-permissive microenvironment.