Abstract: Objective To explore the roles and potential mechanism of CCAAT/enhancer-binding protein alpha （C/EBPα） in the growth of hepatocellular carcinoma （HCC） cells in vitro. Methods The Hep3B cells were transfected with RNAi lentivirous,and the mRNA and protein of C/EBPα were detected by qRT-PCR and Western blot respectively. The growth of HCC cells in normal glucose （NG,4.5 g/L） and low glucose（LG,1 g/L） were assessed by CCK-8 assay and quantified based on the absorbance value at OD450. The protein levels of O-GlcNAcase（OGA）,O-GlcNAc transferase（OGT） and the whole O-GlcNAcylation in normal glucose and low glucose were detected by Western blot. Results The C/EBPαmRNA level was down-regulated by（7.5±2.3） folds（P<0.05） and its protein was decreased by （8.8±0.25） folds （P<0.001） in transfected with RNAi lentivirous cells （sh-C/EBPα） compared with control cell （sh-Con）. Knocking down C/EBPα promoted the growth of HCC cells in vitro. The growth rates of sh-C/EBPα cells increased by 15.4% （P<0.05） and 25.0% （P<0.01） in low glucose（LG,1 g/L） condition at 48 hours and 72 hours;The protein of OGA decreased by 70.1% （P<0.01）,51.4%（P<0.05） and 6 1.2% （P<0.05） in normal gulucose,low glucose at 24 h and 48 h. Whole O-GlcNAcylation was up-regulated by 80.6% in the C/EBPα knocked-down cells in low glucose at 48 h. Conclusion s The downregulation of CCAAT/enhancer-binding protein alpha promotes the growth of hepatocellular carcinoma cells in vitro likely by increasing O-GlcNAcylation in some extent.

Key words: Hepatoma, CCAAT/enhancer-binding protein alpha, O-GlcNAcylation, In vitro