MicroRNA-124 inhibits proliferation and metastasis of esophageal cancer via negatively regulating NRP1.

ABSTRACT

OBJECTIVE: MicroRNAs are a kind of endogenous, non-coding RNAs, which exert a significant role in pathological processes. Previous studies have reported that microRNA-124 is a tumor suppressor. The specific effect of microRNA-124 on esophageal cancer, however, has not been fully elucidated. This study aims to explore the role of microRNA-124 in esophageal cancer and its underlying mechanism. PATIENTS AND METHODS: MicroRNA-124 expressions in 75 esophageal cancer tissues, paracancerous tissues, and esophageal cancer cell lines were detected by qRT-PCR (quantitative Real-Time Polymerase Chain Reaction). The relationship between microRNA-124 expression, clinical progression, pathological indicators, and prognosis of patients with esophageal cancer was analyzed. For in vitro experiments, we performed CCK-8 (cell counting kit-8), colony formation and transwell assay to detect cell proliferation, migration, and invasion abilities after microRNA-124 overexpression in TE-1 and EC-109 cells, respectively. Western blot was utilized to explore the regulatory role of microRNA-124 in esophageal cancer cells. RESULTS: MicroRNA-124 was downregulated in esophageal cancer tissues than that of paracancerous tissues. Patients with esophageal cancer who had lower expression level of microRNA-124 presented higher tumor stage and metastasis incidence, as well as lower survival rate. In vitro studies demonstrated a decreased cell proliferation and migration abilities after microRNA-124 overexpression. Western blot results showed upregulated PI3K and AKT, and downregulated PTEN in esophageal cancer cells after overexpression of microRNA-124. Furthermore, microRNA-124 was confirmed to negatively regulate NRP1, so as to participate in the development of esophageal cancer. CONCLUSIONS: MicroRNA-124 is downregulated in esophageal cancer tissues, which is remarkably correlated to the development, pathological grade, and poor prognosis of esophageal cancer. Overexpressed microRNA-124 is capable of inhibiting the malignant progression of esophageal cancer via negatively regulating NRP1.