Abstract: Objective　To investigate the expression of B-cell lymphoma-2/Adenovirus E1B interacting protein 3 (BNIP3) of ovarian cancer HO-8910PM cells under normal and hypoxic conditions and its effects on mitophagy, cell invasion and metastasis. Methods　The human highly metastatic ovarian cancer cell line HO-8910PM was divided into three groups: normoxia group, hypoxia group and hypoxia+BNIP3 siRNA group. After 48 hours of treatment, mitophagy was detected by acridine orange staining and transmission electron microscopy. Migration and invasion of HO-8910PM cells were determined by scratch test and Transwell chamber assay. The mRNA and protein expressions of BNIP3 and LC3-Ⅱ were analyzed by qPCR and Western blot assay. Results　Under low oxygen conditions，acridine orange staining showed a significant increase in the incidence of mitophagy in HO-8910PM cells, and transmission electron microscopy showed a significant increase in the number of mitochondrial autophagy of HO-8910PM cells (P＜0.01).  After transfection of BNIP3 siRNA, mitochondrial autophagy, cell migration and invasion were significantly inhibited (P＜0.01). The mRNA and protein expressions of BNIP3 and LC3-Ⅱwere significantly increased in hypoxia group, which decreased significantly after transfection of BNIP3 siRNA under hypoxia (P＜0.01). Conclusion　The inhibition of BNIP3 expression in HO-8910PM cells under hypoxia can significantly inhibit mitophagy and reduce cell migration and invasion.

Key words: mitochondria, autophagy, adenovirus E1B proteins;ovarian neoplasms, tumor cells, cultured, cell movement, neoplasm metastasis, adenovirus E1B interacting protein 3