Yanshan Zhang1, Weizuo Chen2, Huijuan Wang3, Tingting Pan1, Yinguo Zhang4, Chao Li4. 1. Department of Radiotherapy, Tumor Hospital of Wuwei, Wuwei, 733000, Gansu, China. 2. Department of Radiotherapy, Tumor Hospital of Wuwei, Wuwei, 733000, Gansu, China. Weizuo_Chen9wz66@163.com. 3. Department of Tumor Chemotherapy, Tumor Hospital of Wuwei, Wuwei, 733000, Gansu, China. 4. 3Department of thoracic Surgery, Tumor Hospital of Wuwei, Wuwei, 733000, Gansu, China.
Abstract
PURPOSE: MicroRNA-519 (miR-519) has been previously reported to function as a tumor suppressor in several types of malignancies. This study aimed to probe the biological role of miR-519 in esophageal squamous cell carcinoma (ESCC). METHODS: qRT-PCR was utilized to test the miR-519 expression level in ESCC tissues and cells. Clinical value of miR-519 was investigated by Kaplan-Meier method. Function assays were conducted to determine the role of miR-519 in radioresistance of ESCC cells. The miR-519-regulated pathways were determined by Kyoto Encyclopedia of Genes and Genomes pathway analysis. RESULTS: Low expression level of miR-519 was closely correlated with the poor prognosis for overall survival of ESCC patients or patients who received radiotherapy. Functional assays indicated that upregulation of miR-519 made ESCC cells more sensitive to γ-ray radiation and facilitated ESCC cell apoptosis triggered by irradiation treatment via regulating DNA response. Ectopic expression of miR-519 decreased the level of p-AKT and p-mTOR, thus inactivating PI3K/AKT/mTOR signaling pathway after irradiation. CONCLUSION: These observations elucidated that upregulated miR-519 is closely correlated with the radiosensitivity of ESCC cells, which may contribute to finding a new promising target for improving the efficiency of radiotherapy in patients with ESCC.
PURPOSE: MicroRNA-519 (miR-519) has been previously reported to function as a tumor suppressor in several types of malignancies. This study aimed to probe the biological role of miR-519 in esophageal squamous cell carcinoma (ESCC). METHODS: qRT-PCR was utilized to test the miR-519 expression level in ESCC tissues and cells. Clinical value of miR-519 was investigated by Kaplan-Meier method. Function assays were conducted to determine the role of miR-519 in radioresistance of ESCC cells. The miR-519-regulated pathways were determined by Kyoto Encyclopedia of Genes and Genomes pathway analysis. RESULTS: Low expression level of miR-519 was closely correlated with the poor prognosis for overall survival of ESCC patients or patients who received radiotherapy. Functional assays indicated that upregulation of miR-519 made ESCC cells more sensitive to γ-ray radiation and facilitated ESCC cell apoptosis triggered by irradiation treatment via regulating DNA response. Ectopic expression of miR-519 decreased the level of p-AKT and p-mTOR, thus inactivating PI3K/AKT/mTOR signaling pathway after irradiation. CONCLUSION: These observations elucidated that upregulated miR-519 is closely correlated with the radiosensitivity of ESCC cells, which may contribute to finding a new promising target for improving the efficiency of radiotherapy in patients with ESCC.