RESUMO
Accumulating studies have demonstrated the importance of long noncoding RNAs (lncRNAs) during oncogenic transformation. However, because most lncRNAs are currently uncharacterized, the identification of novel oncogenic lncRNAs is difficult. Given that intergenic lncRNA have substantially less sequence conservation patterns than protein-coding genes across species, evolutionary conserved intergenic lncRNAs are likely to be functional. The current study identified a novel intergenic lncRNA, LINC00461 (ECONEXIN) using a combined approach consisting of searching lncRNAs by evolutionary conservation and validating their expression in a glioma mouse model. ECONEXIN was the most highly conserved intergenic lncRNA containing 83.0% homology with the mouse ortholog (C130071C03Rik) for a region over 2500 bp in length within its exon 3. Expressions of ECONEXIN and C130071C03Rik were significantly upregulated in both human and mouse glioma tissues. Moreover, the expression of C130071C03Rik was upregulated even in precancerous conditions and markedly increased during glioma progression. Functional analysis of ECONEXIN in glioma cell lines, U87 and U251, showed it was dominantly located in the cytoplasm and interacted with miR-411-5p via two binding sites within ECONEXIN. Inhibition of ECONEXIN upregulated miR-411-5p together with the downregulation of its target, Topoisomerase 2 alpha (TOP2A), in glioma cell lines, resulting in decreased cell proliferation. Our data demonstrated that ECONEXIN is a potential oncogene that regulates TOP2A by sponging miR-411-5p in glioma. In addition, our investigative approaches to identify conserved lncRNA and their molecular characterization by validation in mouse tumor models may be useful to functionally annotate novel lncRNAs, especially cancer-associated lncRNAs.
Assuntos
Antígenos de Neoplasias/metabolismo , Neoplasias Encefálicas/metabolismo , Carcinogênese/genética , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glioma/metabolismo , MicroRNAs/metabolismo , Oncogenes , RNA Longo não Codificante/metabolismo , Animais , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células , Sequência Conservada , Progressão da Doença , Regulação para Baixo , Glioma/genética , Humanos , Camundongos , Proteínas de Ligação a Poli-ADP-Ribose , Lesões Pré-Cancerosas/genética , RNA Longo não Codificante/genética , Complexo de Inativação Induzido por RNA/metabolismo , Regulação para CimaRESUMO
OBJECTIVE: This study aimed to estimate the effectiveness of a full digital, high definition video system for laryngeal observations. METHODS: A newly available, full digital, high definition video camera and high definition video monitor were used. With an endoscopic adaptor and rigid telescope, laryngoscopy and stroboscopy were performed on patients with various kinds of laryngeal lesions. RESULTS: All laryngeal lesions were observed and recorded by the full digital, high definition video camera without incident. The image quality for laryngoscopy and stroboscopy was far superior to that of a conventional video system, including video-endoscopy. Even tiny structures or lesions could clearly be visualised on the monitor. The still image obtained from the full digital, high definition video camera was 1920 x 1080 pixels and was comparable to that obtained from a still camera. CONCLUSIONS: Full digital, high definition video cameras are now commonplace products and can easily be applied to patients with laryngeal disorders. They provide superior laryngeal images, compared with conventional video systems. Furthermore, high definition video systems are cheaper than proprietary medical video systems. We consider our system to represent an accessible technique of gaining superior laryngeal observation in otolaryngological clinics.