Abstract
Circular RNAs (circRNAs) are aberrantly expressed in various tumors and are associated with tumorigenesis. The present study aimed to determine the role of circRNA_001275 in cisplatin‑resistant esophageal cancer. Three pairs of cisplatin‑resistant tissues and corresponding adjacent tissues were collected and subjected to circRNA chip analysis. Additionally, the effect of circRNA_001275 on cisplatin‑resistant cells was investigated. The relationship between circRNA_001275, microRNAs (miRs) and target genes were analyzed using luciferase assays, and validated via reverse transcription‑quantitative PCR (RT‑qPCR) and western blotting. The results showed that circRNA_001275 was significantly upregulated in cisplatin‑resistant esophageal cancer tissues and cells (P<0.05). Overexpression of circRNA_001275 promoted the proliferation and invasion, and decreased the apoptosis of cisplatin‑resistant cells. On the other hand, circRNA_001275 silencing inhibited cell proliferation and invasion, and promoted cell apoptosis (P<0.05). Dual‑luciferase reporter assays revealed that circRNA_001275 directly binds to miR‑370‑3p, and that Wnt family member 7A (Wnt7a) is targeted by miR‑370‑3p. RT‑qPCR and western blotting further demonstrated that circRNA_001275 serves as an miR‑370‑3p sponge to upregulate Wnt7a expression. In conclusion, the present study revealed that circRNA_001275 was upregulated in cisplatin‑resistant esophageal cancer and promoted cisplatin resistance by sponging miR‑370‑3p to upregulate Wnt7a expression. Therefore, circRNA_001275 may serve as a potential diagnostic biomarker and therapeutic target for patients with cisplatin‑resistant esophageal cancer.