Objective To investigate the relationships of the expression of microRNA-487a-3p (miR-487a-3p) and A kinase-interacting protein 1 (AKIP1) mRNA in the endometrial cancer (EC) tissue with the patient survival within 5 years after surgery. Methods The EC tissue and adjacent normal tissue samples were collected from 130 EC patients who underwent surgical treatment at the Fourth Hospital of Shijiazhuang from September 2016 to April 2019.qRT-PCR was employed to determine the expression levels of miR-487a-3p and AKIP1 mRNA.The patients were followed up for 5 years after surgery to record the survival status.After removal of the patients who missed follow-up,78 surviving patients were recorded as the EC survival group,and 34 deceased patients were recorded as the EC death group.The dual luciferase reporter gene assay was conducted to verify the targeting relationship between miR-487a-3p and AKIP1 mRNA.Comparison was conducted for the expression levels of miR-487a-3p and AKIP1 mRNA between adjacent normal tissue and EC tissue,the expression levels of miR-487a-3p and AKIP1 mRNA in the EC tissue among patients with different clinical pathological parameters,and the clinical pathological parameters and the expression levels of miR-487a-3p and AKIP1 mRNA in the EC tissue between the EC survival group and the EC death group.The correlations of miR-487a-3p and AKIP1 mRNA levels in the EC tissue with the degree of tumor differentiation,International Federation of Gynecology and Obstetrics (FIGO) stage,lymph node metastasis,and depth of muscle invasion were analyzed.The relationships of miR-487a-3p and AKIP1 mRNA with patient prognosis and the risk factors affecting the survival of EC patients within 5 years after surgery were analyzed to evaluate the value of miR-487a-3p and AKIP1 mRNA levels in predicting the survival of EC patients within 5 years after survival. Results The EC tissue showed lower miR-487a-3p level (0.41±0.08 vs. 1.00±0.05;t=71.306,P<0.001) and higher AKIP1 mRNA level (2.35±0.37 vs. 1.00±0.03;t=41.465,P<0.001) than the adjacent normal tissue.The miR-487a-3p low expression group and AKIP1 mRNA high expression group had higher proportions of patients with low tumor differentiation,FIGO stage Ⅲ to Ⅳ,lymph node metastasis,and deep invasion of muscle layer than the miR-487a-3p high expression group and AKIP1 mRNA low expression group,respectively (all P<0.05).The results of dual luciferase reporter gene assay showed that the relative activity of luciferase in the miR-487a-3p small interfering RNA (siRNA)+AKIP1 mRNA-wild type (WT) group was higher than that in the miR-487a-3p empty vector+AKIP1 mRNA-WT group (2.85±0.19 vs. 1.00±0.04;t=23.339,P<0.001).There was no significant difference in the relative activity of luciferase between the miR-487a-3p empty vector+AKIP1 mRNA-mutant type (MUT) group and the miR-487a-3p siRNA+AKIP1 mRNA-MUT group (1.04±0.05 vs. 1.05±0.03;t=0.420,P=0.683).MiR-487a-3p in the EC tissue had negative correlations with AKIP1 mRNA,FIGO stage,lymph node metastasis,and depth of muscle invasion and a positive correlation with the degree of tumor differentiation (all P<0.001).AKIP1 mRNA had positive correlations with FIGO stage,lymph node metastasis,and depth of muscle invasion and a negative correlation with the degree of tumor differentiation (all P<0.001).The 5-year overall survival rates in the miR-487a-3p high expression group and AKIP1 mRNA low expression group (89.47% and 84.91%) were higher than those in the miR-487a-3p low expression group and AKIP1 mRNA high expression group (49.09% and 55.93%),respectively (both P<0.05).The EC death group had higher proportions of patients with low tumor differentiation,FIGO stage Ⅲ to Ⅳ,lymph node metastasis,and deep invasion of muscle layer,higher AKIP1 mRNA level in the EC tissue,and lower miR-487a-3p level than the EC survival group (all P<0.05).Low tumor differentiation,FIGO stage Ⅲ to Ⅳ,lymph node metastasis,deep invasion of muscle layer,low miR-487a-3p level,and high AKIP1 mRNA level were independent risk factors for the survival of EC patients within 5 years after surgery (all P<0.05).The area under curve (AUC) values of miR-487a-3p and AKIP1 mRNA alone (0.785 and 0.789,respectively) were lower than that of their combination (0.908) in predicting the survival of EC patients within 5 years after surgery (both P<0.05). Conclusion The EC tissue has a low miR-487a-3p level and a high AKIP1 mRNA level,both of which are correlated with clinicopathological parameters and prognosis and can be used to predict the survival of EC patients within 5 years after surgery.