Project description:The long noncoding RNA CDKN2B-AS1 harbors a major coronary artery disease risk haplotype, which is also associated with progressive forms of the oral inflammatory disease periodontitis as well as myocardial infarction (MI). Despite extensive research, there is currently no broad consensus on the function of CDKN2B-AS1 that would explain a common molecular role of this lncRNA in these diseases. Our aim was to investigate the role of CDKN2B-AS1 in gingival cells to better understand the molecular mechanisms underlying the increased risk of progressive periodontitis. We downregulated CDKN2B-AS1 transcript levels in primary gingival fibroblasts with LNA GapmeRs. Following RNA-sequencing, we performed differential expression, gene set enrichment analyses and Western Blotting. Putative causal alleles were searched by analyzing associated DNA sequence variants for changes of predicted transcription factor binding sites. We functionally characterized putative functional alleles using luciferase-reporter and antibody electrophoretic mobility shift assays in gingival fibroblasts and HeLa cells. Of all gene sets analysed, collagen biosynthesis was most significantly upregulated (Padj=9.7x10-5 (AUC>0.65) with the CAD and MI risk gene COL4A1 showing strongest upregulation of the enriched gene sets (Fold change = 12.13, Padj = 4.9 x 10-25). The inflammatory "TNFA signaling via NFKB" gene set was downregulated the most (Padj=1x10-5 (AUC=0.60). On the single gene level, CAPNS2, involved in extracellular matrix organization, was the top upregulated protein coding gene (Fold change=48.5, P<9x10-24). The risk variant rs10757278 altered a binding site of the pathogen responsive transcription factor STAT1 (P=5.8x10-6). rs10757278-G allele reduced STAT1 binding 14.4% and rs10757278-A decreased luciferase activity in gingival fibroblasts 41.2% (P=0.0056), corresponding with GTEx data. CDKN2B-AS1 represses collagen gene expression in gingival fibroblasts. Dysregulated collagen biosynthesis through allele-specific CDKN2B-AS1 expression in response to inflammatory factors may affect collagen synthesis, and in consequence tissue barrier and atherosclerotic plaque stability.
Project description:M2-like macrophage upregulated lncRNA ADPGK-AS1 regulates macrophage phenotype and modulates the influence of macrophages on lung tumor apoptosis and migration. Here we identified proteins that interact with ADPGK-AS1 that might give insight into how this regulation this is regulated on molecular level. We were able to identify interaction with mitochondrial ribosomal proteins, leading to regulation of mitochondrial oxidative phosphorylation.
Project description:We identified ADIRF-AS1 as a BMAL1-CLOCK regulated circadian lncRNA. Loss of ADIRF-AS1 in U2OS cells altered rhythmicity of clock-controlled genes and expression of genes associated with cell adhesion and the extracellular matrix (ECM) but did not affect neighboring genes in cis. Affinity based enrichment of U2OS ADIRF-AS1-interacting proteins identified all components of the tumor suppressive PBAF (PBRM1/BRG1) complex. Because PBRM1 is a tumor suppressor mutated in 40% of clear cell renal carcinoma (ccRCC) cases, we studied ccRCC 786O cells and also found PBRM1 bound to ADIRF-AS1. Reducing ADIRF-AS1 expression in 786O and A498 ccRCC cells decreased expression of PBAF-suppressed genes, consistent with ADIRF-AS1 acting to antagonize the function of PBAF. Loss of PBRM1, however, rescued PBAF responsive cell cycle genes in ADIRF-AS1 KO 786O ccRCC cells. Importantly, ADIRF-AS1 expression correlates with survival in human ccRCC, particularly in PBRM1 wild-type, but not mutant PBRM1 tumors. In this regard, loss of ADIRF-AS1 did not affect in vitro 786O cell growth, but strikingly eliminated in vivo tumorigenesis, which was partially rescued by concurrent loss of PBRM1. This rescue, however, requires Matrigel, suggesting a PBRM1-independent function of ADIRF-AS1 in regulating the ECM. Collectively, our findings suggest that ADIRF-AS1 functions partly to antagonize the tumor suppressive effect of the PBAF complex and behaves as an unforeseen BMAL1-regulated, oncogenic lncRNA.
Project description:LncRNA Hypoxia-inducible factor 1α-antisense 1 (HIF1α-AS1) is located on the antisense strand of the important Hypoxia-inducible factor 1α (HIF1α) gene, but being transcribed in antisense direction along the HIF1α promoter. Here we used the 3’end biotinylated HIF1a-AS1 RNA and a control RNA for RNA Pulldown and searched for interacting proteins in nuclear extracts of human umbilical vein endothelial cells (HUVEC).
Project description:Long non-coding RNAs (lncRNAs) comprise a diverse class of gene expression regulators with emerging roles in many biological processes including cancer. Here we show that the expression of the lncRNA Hedgehog Interacting Protein Antisense 1 (HHIP-AS1) is a hallmark feature of human SHH-driven tumors. Importantly, loss of HHIP-AS1 leads to reduced tumor growth in SHH-driven tumors in vitro and in vivo. Our results demonstrate the power of cross-entity transcriptome-wide comparisons to identify novel epigenetic–regulatory lncRNA circuitries underlying human cancers.
Project description:Here we show that the non-conserved lncRNA HHIP-AS1 promotes tumorigenesis in human SHH-driven brain tumors, including medulloblastoma, atypical teratoid / rhabdoid tumors (AT/RT). We reveal that GLI2 regulates a bidirectional promoter shared between the well-characterized SHH regulator HHIP and HHIP-AS1. We found a novel regulatory lncRNA mechanism, termed blocking endogenous RNA (beRNA), extending the concept of competing endogenous RNA (ceRNA), where HHIP-AS1 binds its target DYCN1I2 to avoid miRNA-425-based degradation.
Project description:We identified ADIRF-AS1 as a BMAL1-CLOCK regulated circadian lncRNA. Loss of ADIRF-AS1 in U2OS cells altered rhythmicity of clock-controlled genes and expression of genes associated with cell adhesion and the extracellular matrix (ECM) but did not affect neighboring genes in cis. Affinity based enrichment of U2OS ADIRF-AS1-interacting proteins identified all components of the tumor suppressive PBAF (PBRM1/BRG1) complex. Because PBRM1 is a tumor suppressor mutated in 40% of clear cell renal carcinoma (ccRCC) cases, we studied ccRCC 786O cells and also found PBRM1 bound to ADIRF-AS1. Reducing ADIRF-AS1 expression in 786O and A498 ccRCC cells decreased expression of PBAF-suppressed genes, consistent with ADIRF-AS1 acting to antagonize the function of PBAF. Loss of PBRM1, however, rescued PBAF responsive cell cycle genes in ADIRF-AS1 KO 786O ccRCC cells. Importantly, ADIRF-AS1 expression correlates with survival in human ccRCC, particularly in PBRM1 wild-type, but not mutant PBRM1 tumors. In this regard, loss of ADIRF-AS1 did not affect in vitro 786O cell growth, but strikingly eliminated in vivo tumorigenesis, which was partially rescued by concurrent loss of PBRM1. This rescue, however, requires Matrigel, suggesting a PBRM1-independent function of ADIRF-AS1 in regulating the ECM. Collectively, our findings suggest that ADIRF-AS1 functions partly to antagonize the tumor suppressive effect of the PBAF complex and behaves as an unforeseen BMAL1-regulated, oncogenic lncRNA.
Project description:Objectives: Long non-coding RNAs (lncRNAs) have been shown to play important roles in the development and progression of cancer. However, functional lncRNAs and their downstream mechanisms are largely unknown in the molecular pathogenesis of esophageal adenocarcinoma (EAC) and its progression. Design: lncRNAs that are abnormally upregulated in EACs were identified by RNA-seq analysis, followed by quantitative RT-PCR (qRTPCR) validation using tissues from 31 EAC patients. Cell biological assays in combination with siRNA-mediated knockdown were performed in order to probe the functional relevance of these lncRNAs. Results: We discovered that a lncRNA, HNF1A-AS1, is markedly upregulated in human primary EACs relative to their corresponding normal esophageal tissues (mean fold change 7.2, p<0.01). We further discovered that HNF1A-AS1 knockdown significantly inhibited cell proliferation and anchorage independent growth, suppressed S-phase entry, and inhibited cell migration and invasion in multiple in vitro EAC models (p<0.05). A gene ontological analysis revealed that HNF1A-AS1 knockdown preferentially affected genes that are linked to assembly of chromatin and the nucleosome, a mechanism essential to cell cycle progression. The well-known cancer-related lncRNA, H19, was the gene most markedly inhibited by HNF1A-AS1 knockdown. Consistent to this finding, there was a significant positive correlation between HNF1A-AS1 and H19 expression in primary EACs (p<0.01). In order to identify novel oncogenic lncRNAs in esophageal adenocarcinogenesis, we carried out RNA-seq of a matched NE-BE-EAC tissue pair
Project description:Our data showed that ELF3-AS1 was a nuclear lncRNA, and its biofunction in cancers is largely unknown to date. To explore the function of lncRNA ELF3-AS1 in gastric cancer, loss-of-function study was performed in SGC7901 and AGS cell lines. RNA sequencing studies showed that the expression of almost all the histone coding genes were significantly increased after knocking down of ELF3-AS1 in SGC7901 and AGS cell lines.