Research of biological effect of different dose of satereotactic body radiation therapy on hepatoma Hep G2 ceils / 中国医师杂志

ABSTRACT

Objective To study the biological effect of different dose of satereotactic body radiation therapy (SBRT) on hepatoma Hep G2 Cells.Methods Hep G2 hepatumor cells vitality of 0,2,4,6,8,and 10 Gy doses of SBRT were determined by methyl thiazolyl tetrazolium (MTT) method.The cell colony formation rate and the cell survival fraction were detected.The cell apoptosis was detected by flow cytometry.The expressions of cyclin D1,Bax,Bcl-2,and caspase-3 protein were detected by Western blot.Results Hep G2 cells vitality was obvious inhibitory effect in different doses of SBRT,increasing with the SBRT dose,the cell vitality inhibition [2 Gy group (4.29 ± 0.63) ％,4 Gy group (19.37 ± 4.54) ％,6 Gy group (41.35 ±4.51)％,8 Gy group (86.34 ±5.68)％,10 Gy group (97.24 ±5.41)％] was increased,compared to 0 Gy group [(2.94 ± 0.52) ％],the difference was statistically significant (all P ＜ 0.01 or P ＜0.05).The cell colony formation rate and survival score in different doses of SBRT were statistically lower than the control group,increasing with the SBRT dose,the cell colony formation rate [4 Gy group (83.15 ± 4.71),6 Gy group (65.23 ± 5.47),8 Gy group (41.28 ± 5.36),10 Gy group (8.14 ± 5.22)] and survival score [2 Gy group (95.49 ±3.21),4 Gy group (84.23 ±3.45),6 Gy group (66.08 ± 3.71),8 Gy group (41.82 ± 3.82),10 Gy group (8.25 ± 3.56)] were decreased,compared to 0 Gy group [(98.72 ± 1.23),(100.00 ±0.00)],the differences were statistically significant (all P ＜0.01 or P ＜ 0.05).The cell apoptosis in different doses of SBRT was increased,increasing with the SBRT dose,the Hep G2 cells apoptosis [4 Gy group (13.67 ±4.62),6 Gy group (28.71 ±5.13),8 Gy group (54.16 ±5.24),10 Gy group (76.31 ± 5.17)] were significantly increased,compared to 0 Gy group (1.35 ±0.46),the difference was statistically significant (all P ＜ 0.01).The expressions of cyclinD1,Bax,Bcl-2,and caspase-3 protein in different doses of SBRT were decreased,increasing with the SBRT dose,the cyclin D1 [6 Gy group (1.94 ± 0.57),8 Gy group (1.38 ± 0.41),10 Gy group (0.52 ± 0.34)],Bax[6 Gy group (2.67 ±0.59),8 Gy group (1.73 ±0.45),10 Gy group (0.63 ±0.37)],Bcl-2 [4 Gy group (1.78 ±0.41),6 Gy group (1.03 ±0.35),8 Gy group (0.76 ±0.28),10 Gy group (0.38 ± 0.21)],Caspase-3 [6 Gy group (0.76 ± 0.31),8 Gy group (0.42 ± 0.24),and 10 Gy group (0.24 ± 0.21)] were obviously decreased,compared to 0 Gy group [(3.41 ± 0.75),(4.36 ± 0.87),(2.57 ± 0.46),(1.67 ± 0.55)],the difference was statistically significant (all P ＜ 0.05).Conclusions Different dose of SBRT can reduce Hep G2 cell vitality,enhance radiation sensitivity,have a dose dependent,maybe related to promote cell apoptosis and inhibit the proliferation of protein expression.