MiR‑483 promotes the development of colorectal cancer by inhibiting the expression level of EI24.

Abstract

MicroRNAs (miRs) serve an important role in cell differentiation, proliferation and apoptosis by negatively regulating gene expression at the transcriptional or post‑transcriptional level. EI24 autophagy associated transmembrane protein (EI24) is a tumor suppressor gene that serves an important role in the occurrence and development of digestive system tumors. However, little is known regarding the relationship between EI24 and the prognosis of patients with colorectal cancer (CRC). Our previous study confirmed EI24 as the target molecule of miR‑483, using reporter gene detection. Thus, the aim of the present study was to elucidate the effect of the abnormal expression of miR‑483 on the malignant phenotype of CRC through a series of cell function experiments and nude mice tumorigenicity experiments, and to determine the expression level of EI24, a downstream target gene of miR‑483, in CRC and its relationship with patient prognosis. In CRC tissues and cells, the expression level of miR‑483 was upregulated, while the expression level of EI24 was downregulated. Cell function tests such as MTT assay, cell cycle assay, colony formation assay, Migration and invasion assays and nude mice tumorigenicity experiments demonstrated that the overexpression of miR‑483 promoted the proliferation, invasion and metastasis of CRC. Moreover, the reverse transcription‑quantitative PCR results indicated that overexpression of miR‑483 inhibited the expression level of EI24. The relationship between the clinical data and immunohistochemical results from 183patients with CRC and survival was examined. It was found that the expression level of EI24 was positively associated with the prognosis of patients. As a cancer‑promoting factor, miR‑483 enhances the proliferation, migration and invasion of CRC cells by reducing the expression level of EI24.