Hsa_circ_0046534 accelerates esophageal squamous cell carcinoma proliferation and metastasis via regulating MMP2 expression by sponging miR-339-5p

Esophageal cancer is one of the most malignant gastrointestinal malignancies. Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer in China. In recent years, with developments in basic medicine, it has been demonstrated that the abnormal expression of circular RNA (circRNA) plays an important role in the progression and prognosis of ESCC. This study explored the role and downstream molecular mechanisms of circ_0046534 in ESCC. We identified circ_0046534, which was found to be highly expressed in ESCC tissues and cells. Moreover, the downregulation of circ_0046534 inhibited the proliferation, migration and invasion of ESCC cells and the growth and metastasis of ESCC tumours in vivo. Dual-luciferase reporter assays showed that circ_0046534 sponged miR-339-5p and inhibited the expression of miR-339-5p. Furthermore, MMP2 was identified to be a direct target of miR-339-5p through bioinformatics analysis. In addition, the knockdown of circ_0046534 inhibited the expression of the downstream target gene matrix metalloproteinase 2 (MMP2) by releasing the adsorption of miR-339-5p. Taken together, this study demonstrated that silencing circ_0046534 inhibited the growth and metastasis of ESCC through the miR-339-5p/MMP2 pathway. Circ_0046534 is expected to serve as a new biomarker and target for ESCC and provide a new direction for its diagnosis and treatment.