MicroRNA-920 enhances chemosensitivity in esophageal cancer by targeting yes-associated protein 1

Abstract

Objective To study the expression of protein yes-associated protein 1(YAP1) in esophageal carcinoma and its relationship with chemotherapy tolerance and the role of microRNA (miRNA, miR)-920 in the regulation of YAP1 expression. Methods Immunohistochemical technique was used to detect the expression of YAP1 in 30 cases of esophageal cancer tissues and paired normal tissues. Small interfering RNA (siRNA) interference technology combined with real-time quantitative polymerase chain reaction (Real-time PCR) and 3-(4, 5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) experiment was used to detect the expression of YAP1 and its correlation with chemosensitivity in esophageal cancer cell lines. The esophageal cancer stem cells were sorted by flow cytometry, and the expression of YAP1 was examined by Real-time PCR and Western blotting. The siRNA interference technology in combination with stem cell microspheres culture method was used to test the role of YAP1 in maintaining activity of tumor stem cells. Bioinformatics software was used to predict miRNAs targeting YAP1, and miRNA quantitative PCR was used to determine the expression difference of candidate miRNA. Transfection of miRNA analog combined with Western blotting was carried out to verify the targeting regulatory effects of the candidate miRNA on YAP1. Finally, MTS was used to detect the role of miR-920 in the chemotherapy of esophageal carcinoma. Results The expression of YAP1 in 30 cases of esophageal carcinoma tissues (5.300±0.559) was obviously higher than normal tissues (2.200±0.327, P=0.001), and interfering with YAP1 could increase the chemosensitivity of esophageal carcinoma (DDP group, P=0.003, PTX group, P=0.000). Moreover, the expression of YAP1 in the tumor stem cell populations (SP) of esophageal cancer (5.667±0.636) was obviously higher than non-SP cell (1.267±0.176, P=0.002). In addition, the expression of miR-920 in esophageal cancer was negatively correlated with the expression of YAP1. Conclusion MiR-920 can inhibit the expression of YAP1 and increase the chemosensitivity of esophageal carcinoma. Key words: MicroRNA-920; Yes-associated protein 1; Esophageal cancer; Chemosensitivity