Objective      To investigate the effect of Wnt signal pathway on proliferation and apoptosis of rh-endostatin (ES) induced hepatocellular carcinoma cell SMMC-7721 and the possible m

echanism.       Methods      Hepatocellular carcinoma cell SMMC-7721 was treated with different concentrations of rh-endostatin (50

100

200 and 400 μg/ml

respectively) in vitro. MTT assay was used to detect cell proliferation in ES treatment at different concentrations and different time intervals. Flow cytometry was used to detect effect of ES on cell cycle and apoptosis. Protein contents of β-catenin and glycogen synthase kinase-3β (GSK-3β) were determined by Western blotting. mRNA expressions of Wnt signaling pathway downstream genes survivin and cyclin D1 were determined by reverse transcription-polymerase chain reaction (RT-PCR).       Results      ES significantly inhibited the growth of SMMC-7721 cells in a time and dose dependent manner. After ES treatment for 48 and 72 h

the inhibition rates of SMCC-7721 cell were (10.45±0.73)% and (21.81±0.55)% (50 μg/ml)

(15.42±1.91)% and (27.81±0.92)% (100 μg/ml)

(23.64±0.43)% and (31.07±0.13)% (200 μg/ml) and (28.88±0.63)% and (43.76±0.55)% (400 μg/ml)

respectively

which were significantly different from that of 24 h treatment (P=0.000). The proportion of SMMC-7721 cells arrested in G

1

phase after ES treatment was significantly different from that of the control (P=0.000). After ES treatment for 72 h

SMMC-7721 cell apoptosis rate increased in a dose dependent manner and was significantly different from that of the control (P0.05). Western blotting showed that protein expression of β-catenin in SMMC-7721 cells was significantly inhibited by ES

but GSK-3β protein expression was not affected. mRNA expressions of Wnt signal pathway downstream genes survivin and cyclin D1 decreased after ES treatment.       Conclusion      ES can inhibit proliferation and induce apoptosis in hepatocellular carcinoma cell SMMC-7721 by inhibiting protein expression of β-catenin and mRNA expressions of survivin and cyclin D1. The inhibitory effect of ES on cell proliferation and apoptosis is not related to protein expression of GSK-3β.