Abstract
Long interspersed element-1 (LINE-1) retrotransposons are autonomous mobile DNA elements with unique activity that account for about one-fifth of the human genome. Recently, it has been reported that the expression of LINE-1 is closely related to cancer prognosis, and LINE-1 hypomethylation might contribute to the acquisition of aggressive tumor behavior. Despite the importance of LINE-1 expression in cancers, research on the expression of LINE-1 open reading frame (ORF) proteins is very limited. Here, we investigated the expression profiles of LINE-1 ORF1p in ovarian cancer tissue microarrays containing 100 surgical specimens including adjacent normal ovary tissue, primary ovarian cancers, and metastatic ovarian cancers in lymph node. The tissue microarray was stained with mouse monoclonal antibody to LINE-1 ORFp1 for immunofluorescence analysis, and expression levels were evaluated by image analysis. LINE-1 ORFp was significantly overexpressed in ovarian cancers compared with normal tissues and especially upregulated in metastatic ovarian cancers. In addition, the expression of LINE-1 ORF1p was significantly higher in older ovarian cancer patients compared with young patients. These results indicate that expression of LINE-1 ORF1p is related to the progression of ovarian cancers and, in particular, to the age of the patient and the metastatic potential of the cancer.
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This study was supported by Biomedical Research Institute Grant (2015-22), Pusan National University Hospital.
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Ka Yeong Yun declares that he has no conflict of interest. Eun Ji Ko declares that he has no conflict of interest. Heung Yeol Kim declares that he has no conflict of interest. Ji Young Lee declares that he has no conflict of interest. Wan Kyu Eo declares that he has no conflict of interest. Mee Sun Ock declares that he has no conflict of interest. Heui-Soo Kim declares that he has no conflict of interest. Ki Hyung Kim declares that he has no conflict of interest. Hee-Jae Cha declares that he has no conflict of interest.
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Yun, K.Y., Ko, E.J., Kim, H.Y. et al. Long interspersed element-1 open reading frame 1 protein expression profiles in ovarian cancers. Genes Genom 39, 1157–1162 (2017). https://doi.org/10.1007/s13258-017-0589-5
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DOI: https://doi.org/10.1007/s13258-017-0589-5