The 8q24 Enhancer Region including rs6983267 Directly Interacts with Promoter of Oncogenic LncRNA CARLo-5
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ABSTRACT: The mechanism by which rs6983267 at 8q24.21 increases cancer risk is unclear for the lack of protein?coding genes in the region although the variant is strongly associated with cancer pathogenesis. Here we identify long non-coding RNAs (lncRNAs) near the 8q24 region and show that expression of lncRNA CARLo-5 is significantly correlated with the risk allele of the cancer-associated variant rs6883267. We further report that the 8q24 enhancer region including the variant directly interacts with active regulatory region of the lncRNA CARLo-5 promtoer. Finally, we demonstrate that CARLo-5 has an oncogenic function by regulating cell proliferation and cell-cycle. Our data provide new insight of disease-related variants in a gene desert. Comparison and identification of cell cycle-related genes differentially expressed by CARLo-5 knockdown using Nanostring analysis in HCT116 cells.
Project description:Idetification of cell cycle-related genes dysregulated by knockdown of MYCLos (lncRNAs) in colorectal cancer-derived HCT116 and in prostate cancer-derived PC3 Using siRNAs targeting MYCLos, the cells were transfected and RNA samples from the treated cells were subjected to Nanostring Gene Expression Assay
Project description:The mechanism by which rs6983267 at 8q24.21 increases cancer risk is unclear for the lack of protein?coding genes in the region although the variant is strongly associated with cancer pathogenesis. Here we identify long non-coding RNAs (lncRNAs) near the 8q24 region and show that expression of lncRNA CARLo-5 is significantly correlated with the risk allele of the cancer-associated variant rs6883267. We further report that the 8q24 enhancer region including the variant directly interacts with active regulatory region of the lncRNA CARLo-5 promtoer. Finally, we demonstrate that CARLo-5 has an oncogenic function by regulating cell proliferation and cell-cycle. Our data provide new insight of disease-related variants in a gene desert.
Project description:An inherited variant on chromosome 8q24, rs6983267, is significantly associated with cancer pathogenesis. We present evidence that this region is a transcriptional enhancer, that the risk region physically interacts with the MYC proto-oncogene, and that the alleles of rs6983267 differentially bind transcription factor 7-like 2 (TCF7L2). These data provide strong support for a biological mechanism underlying this non-protein coding risk variant.
Project description:Cutaneous squamous cell carcinoma (cSCC) is the second most commonly diagnosed cancer in the United States each year. Despite a generally good prognosis, metastatic cSCC results in over 3500 deaths annually. There are no specifically targeted therapies or biomarkers for metastatic cSCC. To determine whether aberrant microRNA expression occurs in metastatic cSCC which could provide novel targets for therapy or biomarkers for earlier diagnosis or prognosis, microRNA expression profiling was performed in 48 samples including normal skin, primary tumors and metastases. Multiple microRNAs showed differential expression; miR-4286, miR-200a-3p and miR-148-3p showed increased expression and miR-1915-3p, miR-205-5p, miR-4516 and miR-150-5p showed reduced expression in metastatic samples. Several microRNAs previously showing aberrant expressionshown to be aberrantly expressed in primary cSCCs were also observed in this study including miR-100, miR-135b, miR-145, miR-21, and miR-214. In summary, several microRNAs show differential expression between primary and metastatic cSCCs; these may be useful as biomarkers for metastasis or as targets for therapytherapeutic targets. RNA extracted from primary human tissues
Project description:Chromosome instability is a key event in cancer progression. The essential histone H3 variant CENP-A plays a fundamental role in defining centromere identity, structure, and function, but is innately overexpressed in several types of solid cancers. In the cancer background, excess CENP-A is deposited ectopically on chromosome arms, including at the 8q24/cMYC locus, by invading transcription-coupled H3.3 chaperone pathways. Intriguingly, in many cancers, transcription of lncRNAs is upregulated and correlates with poor prognosis, therapeutic resistance, and cancer recurrence in patients. Here, we report that the transcription of chromosome 8q24-derived oncogenic lncRNAs plays an unanticipated role in altering the chromatin landscape of the 8q24 locus. We report that transcription of oncogenic ncRNAs and associated R-loop formation at the 8q24 genomic locus results in the recruitment of H3.3 chaperone-CENP-A histone variant complexes to 8q24. Finally, we demonstrate that a transgene cassette which encodes a specific oncogenic lncRNA from the 8q24 region integrated into a naïve chromosome locus, recruits CENP-A to the new location specifically in a cis-acting manner. These data provide a plausible mechanistic link between locus-specific oncogenic lncRNAs, aberrant local chromatin structure, and the generation of new epigenetic memory in human cancer cells.
Project description:Chromosome instability is a key event in cancer progression. The essential histone H3 variant CENP-A plays a fundamental role in defining centromere identity, structure, and function, but is innately overexpressed in several types of solid cancers. In the cancer background, excess CENP-A is deposited ectopically on chromosome arms, including at the 8q24/cMYC locus, by invading transcription-coupled H3.3 chaperone pathways. Intriguingly, in many cancers, transcription of lncRNAs is upregulated and correlates with poor prognosis, therapeutic resistance, and cancer recurrence in patients. Here, we report that the transcription of chromosome 8q24-derived oncogenic lncRNAs plays an unanticipated role in altering the chromatin landscape of the 8q24 locus. We report that transcription of oncogenic ncRNAs and associated R-loop formation at the 8q24 genomic locus results in the recruitment of H3.3 chaperone-CENP-A histone variant complexes to 8q24. Finally, we demonstrate that a transgene cassette which encodes a specific oncogenic lncRNA from the 8q24 region integrated into a naïve chromosome locus, recruits CENP-A to the new location specifically in a cis-acting manner. These data provide a plausible mechanistic link between locus-specific oncogenic lncRNAs, aberrant local chromatin structure, and the generation of new epigenetic memory in human cancer cells.
Project description:Chromosome instability is a key event in cancer progression. The essential histone H3 variant CENP-A plays a fundamental role in defining centromere identity, structure, and function, but is innately overexpressed in several types of solid cancers. In the cancer background, excess CENP-A is deposited ectopically on chromosome arms, including at the 8q24/cMYC locus, by invading transcription-coupled H3.3 chaperone pathways. Intriguingly, in many cancers, transcription of lncRNAs is upregulated and correlates with poor prognosis, therapeutic resistance, and cancer recurrence in patients. Here, we report that the transcription of chromosome 8q24-derived oncogenic lncRNAs plays an unanticipated role in altering the chromatin landscape of the 8q24 locus. We report that transcription of oncogenic ncRNAs and associated R-loop formation at the 8q24 genomic locus results in the recruitment of H3.3 chaperone-CENP-A histone variant complexes to 8q24. Finally, we demonstrate that a transgene cassette which encodes a specific oncogenic lncRNA from the 8q24 region integrated into a naïve chromosome locus, recruits CENP-A to the new location specifically in a cis-acting manner. These data provide a plausible mechanistic link between locus-specific oncogenic lncRNAs, aberrant local chromatin structure, and the generation of new epigenetic memory in human cancer cells.
Project description:An inherited variant on chromosome 8q24, rs6983267, is significantly associated with cancer pathogenesis. We present evidence that this region is a transcriptional enhancer, that the risk region physically interacts with the MYC proto-oncogene, and that the alleles of rs6983267 differentially bind transcription factor 7-like 2 (TCF7L2). These data provide strong support for a biological mechanism underlying this non-protein coding risk variant. Total RNA and genomic DNA were isolated from colon tissue in 5 individuals. cDNA and DNA were analyzed on separate tracks, with the genomic DNA used to identify sprurious cross-hybridization
Project description:We generated H460 cells with acquired TRAIL resistance by exposing the parental sentisitve cells to subtoxic concentrations of TRAIL for 6 months. Then we compared the microRNA expression profile in the sensitive versus resistant cells. H460 cells were treated with subtoxic concentrations of TRAIL for 6 month. After confirmation of the resistance, the RNA was extracted and the microRNA expression profile was analyzed using the NanoString technology.
Project description:Introduction: Amplification at chromosome 8q24 is one of the most frequent genomic abnormalities in human cancers and is associated with reduced survival duration in breast and ovarian cancers. The minimal amplified region encodes c-MYC and the non-coding RNA, PVT1 including miR-1204 encoded in exon 1b. Here we analyzed the genomic changes at chromosome 8q24.21 in breast cancer and the functional roles of miR-1204 in breast and ovarian cancer progression. Methods: The genomic changes at chromosome 8q24.21 were detected in 997 breast cancer tumors and 40 breast cancer cell lines. Expression of miR-1204 in breast and ovarian cancer cell lines was investigated by qRT-PCR method. The role of miR-1204 in the tumorigenesis of breast and ovarian cancer was explored using both knockdown and overexpression of miR-1204 in vitro. Candidate miR-1204 target genes from two independent expression microarray datasets and computational predict programs were identified and further validated by qRT-PCR and western blot methods. The role of inhibition of miR-1204 on tamoxifen sensitivity in breast cancer cells was also investigated. Results: MiR-1204 is frequently co-amplified with MYC and expression of miR-1204 is strongly correlated with the expression and amplification of the noncoding PVT1 transcript and less so with MYC in human breast and ovarian cancer cells. Inhibition of miR-1204 decreases cell proliferation and increased apoptosis in breast and ovarian cancer cell lines with 8q24 amplification, but not in lines without amplification and so may be involved in Myc-induced apoptosis. Additionally, overexpression of miR-1204 enhances both breast and ovarian cancer cell growth and Myc-initiated Rat1A cell transformation. Computational and experimental analyses 30 promising candidate miR-1204 target genes. mRNA levels for these genes were assessed after over expression and knockdown of miR-1204 as were protein levels for 10 genes for which antibodies were available. These studies implicated VDR and ESR1 as miR-1204 targets. Inhibition of miR-1204 increased response to tamoxifen in Estrogen Receptor negative breast cancer cell lines. Conclusions: We conclude that amplification of miR-1204 contributes to breast and ovarian pathophysiology at least in part, by increasing proliferation and down regulating apoptosis and by decreasing expression of VDR and ESR1. Seven cell line sample pairs, where samples are LNA transfected with antimiR-1204 or antimiR-1204 control