MiR-133a-3p inhibits the malignant progression of oesophageal cancer by targeting CDCA8

The study aims to explore the interaction between miR-133a-3p and cell division cycle associated 8 (CDCA8) in oesophageal cancer (EC) and their effect on malignant behaviour of EC cells. Differential miRNAs and mRNAs were obtained from The Cancer Genome Atlas (TCGA) database. Quantitative real-time PCR (qRT-PCR) was used to detect the expression levels of miR-133a-3p and CDCA8 mRNA in EC cells. Western blot was used to detect the expression of CDCA8 protein. CCK-8, flow cytometry and Transwell assays were conducted to detect cell proliferation, cell cycle and apoptosis, as well as migration and invasion, respectively. The targeting relationship between miR-133a-3p and CDCA8 was verified by dual-luciferase reporter gene assay. In EC, miR-133a-3p expression was evidently low and CDCA8 expression was prominently high. MiR-133a-3p downregulated CDCA8 expression. A range of cell function experiments revealed that CDCA8 promoted the proliferation, migration and invasion of EC cells, reduced cell cycle arrest in G0/G1 phase and inhibited cell apoptosis, while miR133a-3p could reverse the above effects by regulating CDCA8. MiR-133a-3p is a crucial tumour suppressor miRNA in EC, playing a tumour suppressor role by targeting CDCA8.