表观遗传学药物FK228治疗肝癌的实验研究

目的观察表观遗传学药物FK228对人肝癌细胞HepG2的体内外抑制作用,并初步探讨其机制。方法采用不同浓度的FK228和氟尿嘧啶(5-FU)处理HepG2细胞48 h,采用CCK-8法观察比较FK228对人肝癌细胞HepG2的生长抑制作用。将5μg/L FK228和25μg/ml 5-FU分别单独或联合作用于2种肝癌细胞48 h,使用流式细胞仪检测细胞凋亡率。体内实验构建BALB/c裸鼠皮下移植瘤模型,通过腹腔注射FK228 (1 mg/kg)和5-FU (20 mg/kg),比较FK228对HepG2裸鼠移植瘤生长抑制作用。结果 FK228对人肝癌细胞HepG2具有明显的生长抑制作用,且呈剂量依赖性,其48 h的半数抑制浓度(IC50)为(4.20±0.24)μg/L,而5-FU的IC50值为(117.50±8.40)μg/ml;FK228联合5-FU处理组与相应浓度的单药组相比,联合用药组的细胞存活率明显降低(P<0.05)。流式细胞仪检测结果显示,FK228可以显著诱导肝癌细胞HepG2凋亡,且联合用药后细胞凋亡率明显增加(P<0.05)。给药20 d后,FK228组、5-FU组、联合给药组及对照组的肿瘤体积分别为(344.71±118.87)、(351.97±73.46)、(220.36±72.12)、(639.76±241.47)mm3。FK228组、5-FU组、联合给药组的裸鼠肿瘤体积均小于对照组(P<0.05)。免疫组化结果显示,与对照组相比,FK228对肝癌细胞的体内促凋亡作用并不明显(P>0.05),但与5-FU联合应用后,促凋亡作用明显增强(P<0.05);与对照组和5-FU组相比,FK228可以明显抑制肿瘤内的血管生成(P<0.05)。结论 FK228对人肝癌细胞HepG2具有明显的体内外生长抑制作用,且与5-FU联合应用后,抑制作用更加明显。FK228与5-FU联合应用,可以明显促进HepG2肝癌细胞的凋亡和抑制肿瘤的血管生成。

Experimental study of epigenetic drug FK228 in the treatment of hepatocellular car-cinoma

Objective To observe the inhibition effects of epigenetic drug FK228 on human hepatoma cell lines HepG2 in vivo and in vitro,and to explore its mechanism.Methods The HepG2 cells were treated by different concentrations of FK228 and 5-FU for 48 hours,and the inhibition effect on growth was determined by CCK-8 assay;the cell apoptosis of HepG2 cells treated by 5μg/L FK228 and 25μg/ml 5-FU alone or in combination for 48 hours was evaluated by flow cytometry.The nude mice model bearing subcutaneous tumor was established,and the inhibition effects of FK228 on the growth of transplanted tumor in nude mice was compared after being given intraperitoneal in-jection of FK2281 mg/kg and 5-FU 20 mg/kg.Results FK228 could inhibit the growth of HepG2 cells in a dose-de-pendent manner.The IC 50 values of FK228 at 48 h were(4.20±0.24)μg/L,and the IC 50 values of 5-FU were(117.50±8.40)μg/ml.The cell survival rate of the combination group was significantly lower than that of the single drug group(P<0.05).Flow cytometry results showed that FK228 could induce the apoptosis of HepG2 cells signifi-cantly,and the apoptosis rate of HepG2 cells increased significantly after the combination use of FK228 and 5-FU(P<0.05).The volume of tumor in FK228 group,5-FU group,combination group and control group was(344.71±118.87),(351.97±73.46),(220.36±72.12),and(639.76±241.47)mm 3,respectively.The tumor volume of FK228 group,5-FU group and combination group was smaller than that of control group(P<0.05).The results of im-munohistochemical staining of tumor sections showed that FK228-induced apoptosis in vivo had no significant differ-ence compared to control group(P>0.05),but the apoptosis induced by the combination use of FK228 and 5-FU was enhanced significantly(P<0.05);compared with control group and 5-FU group,the inhibition effect on tumor angio-genesis was increased in FK228 group(P<0.05).Conclusion FK228 has a significant inhibition effect on the growth of HepG2 cells in vitro and in vivo,which is more significant after being combined with 5-FU.The combination use of FK228 and 5-FU can significantly promote the apoptosis of HepG2 cells and inhibit tumor angiogenesis.