Objective    To study the differential expression of the spindle checkpoint protein BubR1 gene between human hepatoma tissue and human hepatic tissue

and between human hepatoma carcinoma cell line HepG2 and human hepatic normal cell line LO2 during mitotic period.     Methods    Nocodazole was employed to synchronize their cell phase at dividing phase. Real-time fluorescent-quantitation PCR and Western blotting were respectively employed to detect the expressions of BubR1 mRNA and protein.     Results    The expressions of BubR1 mRNA and protein in human hepatic tissue was higher than that in human hepatoma tissue. The expressions of BubR1 mRNA and protein showed no significant difference between HepG2 and LO2 cell lines before Nocodazole treatment. After being treated with Nocodazole

the expressions of BubR1 mRNA and protein in both cell lines were significantly increased and the increment in LO2 cells was higher than that in HepG2 cells.     Conclusion    Low expression of BubR1 gene is likely to play an important role in the genesis and development of human primary hepatocellular carcinoma.