1. Significance of Circular FAT1 as a Prognostic Factor and Tumor Suppressor for Esophageal Squamous Cell Carcinoma
- Author
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Hirotaka Furuke, Jun Shibamoto, Shuhei Komatsu, Tomohiro Arita, Kiyoshi Masuda, Katsutoshi Shoda, Atsushi Shiozaki, Wataru Takaki, Kazuya Takabatake, Hitoshi Fujiwara, Hirotaka Konishi, Eigo Otsuji, Hiroki Shimizu, and Satoshi Kataoka
- Subjects
0303 health sciences ,business.industry ,Cell migration ,Reverse transcription polymerase chain reaction ,03 medical and health sciences ,0302 clinical medicine ,Oncology ,Downregulation and upregulation ,Surgical oncology ,Cell culture ,Circular RNA ,030220 oncology & carcinogenesis ,Cancer research ,Medicine ,Biomarker (medicine) ,Surgery ,business ,030304 developmental biology ,FAT1 - Abstract
Background Circular RNA is a novel endogenous non-coding RNA with a stable loop structure, and theories for its biogenesis and usefulness as a biomarker in various cancers have been proposed. The present study investigated the significance of circular FAT1 (circFAT1) as a novel biomarker in esophageal squamous cell carcinoma (ESCC). Method CircFAT1 expression levels were measured in ESCC cell lines and the effects of downregulating circFAT1 on cell migration and invasion were examined using a transwell assay. The functions of miR-548g, which will be sponged by circFAT1, were assessed. Furthermore, the expression of circFAT1 was evaluated in 51 radically resected ESCC tissue samples using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The relationships between circFAT1 expression, clinicopathological factors, and patient prognosis were analyzed. Results CircFAT1 expression levels were significantly lower in tumor tissue than in adjacent non-tumorous mucosal tissue (p = 0.01). The downregulation of circFAT1 expression promoted ESCC cell migration and invasive ability, but not proliferation. The expression of miR-548g was upregulated by the downregulation of circFAT1. The overexpression of miR-548g also promoted ESCC cell migration and invasion. Recurrence-free survival (p = 0.02) and cancer-specific survival (p = 0.04) rates were significantly higher in patients with elevated circFAT1 expression levels. Conclusion The expression level of circFAT1 is a novel prognostic marker in ESCC patients. New treatment strategies may be developed using the tumor suppressive functions of circFAT1.
- Published
- 2021