Abstract: Objective To observe the expression of the C-terminal truncated human apoptosis-inducing factor (AIF) and its
biological effect on MCF-7 cells. Methods PcDNA3.0-FDT-AIFΔ1-480 was transfected into human breast carcinoma MCF-7
cells with lipofectamins. The expression of the truncated AIF gene was detected by Western blotting, and its effects on the
biological behaviors of MCF-7 cells and on the expression of cytochrome c (cytC) were evaluated using flow cytometry, MTT
assay, colony-forming assay, and mitochondrial membrane potential measurement. Results PcDNA3.0-FDT-AIFΔ1-480
enhanced AIF expression in MCF-7 cells, obviously inhibited the cell proliferation, and significantly reduced the mitochondrial
membrane potentials (P<0.05). Transfection of the cells with PcDNA3.0-FDT-AIFΔ1-480 promoted the expression of cytC and
resulted in significantly increased apoptosis of MCF-7 cells (P<0.05). Conclusion The expression of C-terminal truncated
human AIF gene can induce apoptosis of human MCF-7 cells by promoting cytC release from mitochondria.