Abstract： Objective To study the effect of circRNA_002178 gene interference on malignant biological behavior of ovarian cancer cells.Methods Human ovarian cancer SKOV3 cells were di-vided into 4 groups:control group,short hairpin RNA negative control(shRNA-NC)group,cir-cRNA_002178-shRNA 1 group and circRNA_002178-shRNA 2 group.The expression level of cir-cRNA_002178 was detected by real-time fluorescence quantitative polymerase chain reaction(RT-PCR).Flow cytometry was used to detect the cell apoptosis and mitochondrial membrane potential and to select the stem cell positive(CD44,CD133)cell lines.The stem cell spheroidization test was used to detect the sphere formation rate and the diameter of spheres.Transwell assay was used to detect the cell invasion.Western blotting was used to detect the expression levels of the proteins.The transplanted tumor model was constructed to observe the effect of circRNA_002178 gene interference on tumor formation.Results CircRNA_002178 interference significantly promoted the apoptosis of SKOV3 cells,decreased the number of CD44 and CD133 positive cells,the rate of sphere forma-tion,the diameter of spheres and the number of invasive cells,intensified the changes of mitochon-drial membrane potential,and inhibited tumor growth and Akt/mTOR pathway activation in trans-planted tumor rats.Conclusion CircRNA_002178 interference can inhibit the malignant biological behavior of ovarian cancer cells.The mechanism may be related to the inhibitory effect on Akt/mTOR pathway.