Objective:To investigate the effect of miRNA-3653-3p (miR-3653-3p) on the proliferation and invasion ability of endometrial cancer cells and its related mechanisms.Methods:The data of 356 endometrial cancer patients were downloaded from the OncoLnc database (http://www.oncolnc.org, updated version 2020), and the Kaplan-Meier method was used to analyze the relationship between the expression level of miR-3653-3p and the overall survival of endometrial cancer patients. The miRGator database (https://bio.tools/mirgator_v2.0, updated version 2019) was used to predict the target gene binding to miR-3653-3p. Human endometrial cancer cell lines AN3CA, HEC-1A, HEC-1B, Ishikawa and human normal endometrial epithelial cell line ESC were selected, and the relative expression level of miR-3653-3p was detected by using quantitative real-time fluorescent polymerase chain reaction (qRT-PCR). The cell line with the lowest expression of miR-3653-3p was selected as the research object, which was divided into the negative control group and miR-3653-3p group, and transfected with the control empty vector plasmid and miR-3653-3p overexpression plasmid. CCK-8 method was used to detect the proliferation ability of cells, Transwell method was used to detect the invasion ability of cells, and qRT-PCR and Western blot were used to detect the expression of miR-3653-3p target gene. The effect of miR-3653-3p on the related protein expression of Wnt- β-catenin signaling pathway was detected by using Western blot.Results:Data analysis in the OncoLnc database showed that compared with endometrial cancer patients with low miR-3653-3p expression, patients with high miR-3653-3p expression had better overall survival ( P < 0.01). Compared with human normal endometrial epithelial ESC, the expression levels of miR-3653-3p in endometrial cancer cell lines AN3CA, HEC-1A, HEC-1B, and Ishikawa were all decreased (all P < 0.05), and the relative expression level of miR-3653-3p was the lowest in HEC-1A cells, and HEC-1A cells were selected for subsequent experiments. The result of CCK-8 showed that compared with the negative control group, the ability of HEC-1A cells in the miR-3653-3p group decreased on the 2nd, 3rd, 4th, and 5th days (all P < 0.05). The result of the Transwell chamber invasion test showed that the number of HEC-1A cell invasion after culturing for 26 h in the negative control group and the miR-3653-3p group was (80±11) and (21±4), respectively, and the difference was statistically significant ( t = 5.18, P < 0.01); compared with the negative control group, the number of cell invasion in the miR-3653-3p group decreased. The miRGator database was used to predict that the target gene of miR-3653-3p might be placenta-specific protein 8 (PLAC8). The relative expression levels of PLAC8 mRNA in HEC-1A cells in the negative control group and miR-3653-3p group were (6.26±0.83) and (0.97±0.31), respectively, and the difference was statistically significant ( t = 6.00, P < 0.01); the relative expression level of PLAC8 mRNA in the miR-3653-3p group was lower than that in the negative control group. Compared with the negative control group, the PLAC8 protein of HEC-1A cells decreased, and the expression of Wnt-β-catenin signaling pathway related proteins β-catenin, transforming growth factor β (TGF-β), GSK-3β, and Rac1 decreased in the miR-3653-3p group. Conclusions:miR-3653-3p may inhibit the proliferation and invasion of endometrial cancer cells by regulating the PLAC8-Wnt-β-catenin signaling pathway.