Objective    To study the expression of hypoxia inducible factor-1α (HIF-1α) in BGC-823 cells after RNA interference and the proliferation and apoptosis of BGC-823 cells.     Methods    The recombinant plasmid pshRNA-HIF-1α was constructed and transfected into gastric cancer cells BGC-823 by Lipofectamine

TM

2000. Then the expressions of HIF-1α in BGC-823 cells were observed by RT-PCR and Western blotting

the cell

proliferation was examined by MTT assay and the cell apoptosis by TUNEL and flow cytometry. The transfected cells were transplanted to nude mice to observe the inhibitory effect of transfection.     Results    The restriction enzyme digestion and sequencing result showed that the recombinant plasmid of pshRNA-HIF-1α had been constructed successfully. After it was transfected into BGC-823 cells

the genetic transcription and protein expression of HIF-1α were inhibited significantily (inhibitory ratio: 93.4% and 55.7%)

compared with controls. The inhibitory ratio of cell proliferation in the pshRNA-HIF-1α transfected cells was higher than that of controls

and the cell ratio was increased in G

0

/G

1

phase

and decreased in S and G

2

/M phases. The apoptotic ratio of the cells transfected with pshRNA-HIF-1α was also higher than that of controls. Karyopycnosis

nuclear chromosomal condensation and segmentation were observed by TUNEL. In vivo

pshRNA-HIF-1α1 was proved to be able to inhibit the proliferation and induce the apoptosis of BGC-823 cells by restraining the expressions of HIF-1α

whose tumor inhibition rate was 41.75%.     Conclusion    Our results show that the recombinant plasmid pshRNA-HIF-1α can inhibit the genetic transcription and protein expression of HIF-1α

and suppress the proliferation and induce the apoptosis of gastric cancer cells BGC-823 in vivo and in vitro.