Abstract:Objective To investigate the effects of miR-219a-5p on proliferation, apoptosis, migration and invasion of endometrial cancer cells and its mechanism. Methods The human endometrial cancer cell line AN3CA were cultured and transfected with plasmid, and divided into control group(normal culture), NC group(transfected with NC plasmid), miR-219a-5p group(transfected with miR-219a-5p plasmid), miR-219a-5p group+activator group(transfected with miR-219a-5p plasmid+medium containing PI3K activator 740 Y-P).The cell proliferation, apoptosis, migration and invasion of each group were detected by MTT, flow cytometry, scratch assay and Transwell assay. The protein expression levels of phosphoinositide-3-kinase(PI3K), protein kinase B(AKT) and mammalian rapamycin target protein(mTOR) were detected by Western Blot. The mRNA expressions of miR-219a-5p and PI3K signaling pathway in endometrial cancer and adjacent tissues from patients were detected and verified. Results When the four groups of cells were cultured for 24, 48 and 72 h, the cell proliferation activity of miR-219a-5p group was the lowest (F=18.25, 16.39, 18.96, P＜0.01). Compared with control group, the proportion of apoptosis and cell migration increased, and invasion decreased significantly(P＜0.01), while the expression levels of PI3K, AKT, and mTOR were significantly downregulated in miR-219a-5p group(P<0.01). Compared with miR-219a-5p group, the above indicators in the miR-219a-5p+activator group showed reverse changes(P<0.05). There was no statistically significant difference in the above indicators between the NC group and the control group(P>0.05). Compared with adjacent tissues, the expression level of miR-219a-5p in cancer tissue was significantly reduced, while the mRNA expression of PI3K, AKT, and mTOR was significantly upregulated(P<0.05). Conclusion miR-219a-5p can inhibit the proliferation, migration, invasion and apoptosis of endometrial cancer cells, and its mechanism may be related to the inhibition of PI3K signaling pathway activity.