Objective      To observe the effect of RNA interference (RNAi)-silenced BC047440 gene on multidrug resistance of HepG2/ADM cells and its molecular mechanism.       Methods      BC047440 protein siRNA interference model was established in Hep

G2/ADM cells. Expression of BC047440 protein was detected by Western blotting. Experiment was conducted in BC047440-shRNA group

control-shRNA group and HepG2/ADM group. Effect of adriamycin on cell growth was analyzed with CCK-8 method. Cell cycle and apoptosis were assayed by flow cytometry. Expression of NF-κB protein

Survivin mRNA and CCNL1 mRNA was detected by Western blotting and RT-PCR

respectively

after BC047440 was silenced.       Results      The siRNA interference model was successfully established. The NF-κB protein was expressed about 71.5% in BC047440-shRNA group and HepG2/ADM group

and about 70.0% in control-shRNA group. The cytotoxicity of adriamycin at 24 and 48 h was significantly higher in BC047440-shRNA group. Flow cytometry showed that the number of apoptotic cells was significantly greater in BC047440-shRNA group

the cell cycle was maintained at the G

14

/G

0

phase

and the number of HepG2/ADM cells was reduced at the S phase. RT-PCR showed that the Survivin mRNA was expressed about 37% in control-shRNA group and about 42% in HepG2/ADM group

while the expression of CCNL1 mRNA was about 3.5-fold higher in BC047440-shRNA group than in control-shRNA group and about 2.4-fold higher than in HepG2/ADM group.       Conclusion      Silencing BC047440 gene can reverse the multidrug resistance of HepG2/ADM cells though the NF-κB

and downstream survivin and CCNL1 signaling pathways

which indicates that BC047440 gene may be one of the important molecules for the multidrug resistance of liver cancer.