异鼠李素抑制人胃癌细胞表皮生长因子受体途径

Inhibitive effect of isorhamnetin on epidermal growth factor receptor signal pathway of human gastric carcinoma cells

目的通过体外试验研究异鼠李素抑制人胃癌SGC-7901细胞生长的表皮生长因子受体(EGFR)信号途径。方法分别用0.8×10-4,1.2×10-4,2.4×10-4mol/L的异鼠李素、10%的RPMI 1640、0.048mol/L氟尿嘧啶处理SGC-7901细胞24h后收集细胞,计活细胞数,计算生长抑制率;用Lipofect转染法将EGFR或生长因子受体结合蛋白2(grb2 antisense)分别转入胃癌SGC-7901细胞中,用RT-PCR法分别检测EGFR和grb2 mRNA的表达水平;采用磷酸钙-DNA沉淀转染法测定AP-1活性。结果0.8×10-41.2×10-4,2.4×10-4mol/L异鼠李素和0.048mol/L氟尿嘧啶处理24h后对细胞生长的抑制率分别为55.06%,62.03%,66.46%,70.25%。3个剂量异鼠李素处理细胞后EGFR、grb2 mRNA表达水平、AP-1活性均明显下降,且随着剂量的增加而下降。EGFR、grb2 anti-sense分别转入SGC-7901细胞后,用2.4×10-4mol/L异鼠李素处理24h,阻断EGFR后转染细胞grb2的表达和AP-1活性比未转染的分别提高了62.79%和60%(P<0.05);阻断grb2后转染细胞AP-1活性比未转染的提高36%(P<0.05),而EGFR mRNA表达水平无显著变化(P>0.05)。结论异鼠李素是通过抑制EGFR信号转导途径的激活抑制人胃癌SGC-7901细胞生长。

Objective To study the inhibitive effect of isorhamnetin on epidermal growth factor reeeptor（EGFR） signal pathway of human gastric carcinoma cells in vitro. Methods The inhibitory rate was calculated after the human gastric carcinoma SGC- 7901 cells were treated with 0.8 × 10^- 4, 1.2 × 10^- 4,2.4 × 10^- 4mol/L isorhamnetin, 10 % RPMI, 0. 048mol/ L fluorouracil. Expression of EGFR, grb2 and activity of AP - 1 were measured by RT - PCR and calcium phosphate - DNA eoprecipitation transfection after the SGC - 7901 cells were transfected with EGFR and grh2 antisense by Lipofect. Results Inhibitive rate of 55.06%, 62.03%, 66.46%, 70.25% occurred, respectively after 24h of 0.8 × 10^-4, 1.2 × 10^-4, 2.4 × 10^-4mol/L isorhamnetin and 0. 048mol/L fluorouracll treatment. Expression of EGFR, grb2 mRNA and AP - 1 activity were significantly decreased in a dosedependent manner after 24h of 0.8 × 10^-4, 1.2 × 10^-4, 2.4 × 10^-4mol/L isorhamnetin treatment. The blockage of EGFR significantly increased the expression of grb2 and AP - 1 activity. The transfection of grb2 antisense significantly enhanced AP - 1 activity, but the expression of EGFR mRNA wasn＇ t significantly affected. Conclusion Isorhamnetin can significantly inhibit proliferation of human gastric carcinoma SGC- 7901 cells by controlling the EGFR signal pathway.