9-硝基喜树碱脂质体对肝癌细胞株HepG2的抑制作用及机制

目的 观察9-硝基喜树碱脂质体对HepG2肝癌细胞的抑制作用及其机制.方法 9-硝基喜树碱(9NC)及其脂质体(9NC-LP)处理HepG2细胞后,MTT法测定细胞活性,流式细胞术检测细胞周期及凋亡相关蛋白表达.建立HepG2细胞裸鼠皮下移植瘤模型,随机分为空白对照组,空白脂质体组,DMSO组,9NC低、高剂量组,9NC-LP低、高剂量组,每组10只.尾静脉给药后持续监测各组裸鼠肿瘤体积、体重变化.给药后28 d处死裸鼠,切取肿瘤提取总蛋白后Western Blot检测蛋白表达变化.结果 在体外实验,9NC-LP对肿瘤细胞生长呈时间和剂量依赖性抑制.药物处理后S期和G2/M期细胞明显增多,浓度大于0.1 btmol/L时24 h后细胞完全阻滞于S期;0.1μmol/L 孵育72 h后,超过95%HepG2细胞阻滞于G2/M期.在体内实验,与空白对照组比较,各剂量的9NC及9NC-LP均引起肿瘤体积下降(P<0.05)和裸鼠体重减轻(P<0.05).空白脂质体组与空白对照组、DMSO组比较差异无显著性(P>0.05).肿瘤生长最高抑制率9NC-LP(2.5 mg/kg)组、9NC-LP(1.5 mg/kg)组、9NC(1.5 mg/kg)组,分别为87.02%、51.57%和35.47%.9NC (2.5 mg/kg)组用药14 d过半动物死亡.结论 9NC及9NC-LP可以通过调控细胞周期和诱导凋亡有效抑制肝癌细胞生长.与原料药相比9-硝基喜树碱脂质体在体内对肝癌细胞的抑制增强,副作用减弱.9-硝基喜树碱脂质体是一种极具前景的纳米靶向药物.

Abstract：

Objective To observe the inhibitory effect and mechanism of 9-nitrocamptothecin liposomes on HepG2 liver carcinoma cells. Methods HepG2 cells were incubated with 9-nitrocampto-thecin(9NC) or with 9-nitrocamptothecin liposomes(9NC-LP) for 24 h, 48 h and 72 h. Cell viability was then measured by the MTT assay. Cell cycle and apoptosis were evaluated by flow cytometry.Western Blot was used to determine the expression of cell cycle and apoptosis related proteins. HepG2tumor-bearing mouse models were then established. The HepG2 tumor-bearing mice were randomly divided into control group, free liposomes group, DMSO group, 9NC low dose group, 9NC high dose group, 9NC-LP low dose group and 9NC-LP high dose group. There were 10 mice in each group.Drugs were administered by tail vein and tumor volume and body weight were observed 28 days after administration. Then animals were sacrificed and the expression of proteins from tumor homogenates was analyzed by Western blotting. Results In vitro, HepG2 cell viability was apparently inhibited by 9NC and 9NC-LP, and the inhibitory effect increased in a time-dependent and dose-dependent manner.Both S and G2/M phase arrests were observed after incubation with drugs. HepG2 cells were completely arrested in S phase with 9NC concentration over than 0.1 μmol/L after incubation for 24 h,while more than 95% of cells arrested in G2/M phase when 9NC concentration was 0.1 μmol/L after incubation for 72 h. In vivo, compared with the control group, the average tumor volume was reduced in both the 9NC and 9NC-LP group (P<0.05) , and the average animal body weight also decreased in both the 9NC and 9NC-LP group (P<0.05). There was no significant difference among the control group, free liposomes group, and DMSO group. The lights inhibition rates of tumor growth in the 9NC-LP(2.5 mg/kg),9NC-LP(1.5 mg/kg),and 9NC(1.5 mg/kg)groups were 87.02%, 51.57%and 35.47%, respectively. In the 9NC-LP(2.5 mg/kg)group, >50% of animals died 14 days after drug administration. Conclusion 9NC and 9NC-LP can inhibit HepG2 cell growth via cell cycle arrest and apoptosis induction. 9NC-LP has a more potent anti-tumor effect and fewer side effects in vivo,which means 9NC-LP is a promising compound for cancer therapy via intravenous administration.

In vitro and in vivo inhibitory effects and mechanism of 9-nitrocamptothecin liposomes on HepG2 cell

Objective To observe the inhibitory effect and mechanism of 9-nitrocamptothecin liposomes on HepG2 liver carcinoma cells. Methods HepG2 cells were incubated with 9-nitrocampto-thecin(9NC) or with 9-nitrocamptothecin liposomes(9NC-LP) for 24 h, 48 h and 72 h. Cell viability was then measured by the MTT assay. Cell cycle and apoptosis were evaluated by flow cytometry.Western Blot was used to determine the expression of cell cycle and apoptosis related proteins. HepG2tumor-bearing mouse models were then established. The HepG2 tumor-bearing mice were randomly divided into control group, free liposomes group, DMSO group, 9NC low dose group, 9NC high dose group, 9NC-LP low dose group and 9NC-LP high dose group. There were 10 mice in each group.Drugs were administered by tail vein and tumor volume and body weight were observed 28 days after administration. Then animals were sacrificed and the expression of proteins from tumor homogenates was analyzed by Western blotting. Results In vitro, HepG2 cell viability was apparently inhibited by 9NC and 9NC-LP, and the inhibitory effect increased in a time-dependent and dose-dependent manner.Both S and G2/M phase arrests were observed after incubation with drugs. HepG2 cells were completely arrested in S phase with 9NC concentration over than 0.1 μmol/L after incubation for 24 h,while more than 95% of cells arrested in G2/M phase when 9NC concentration was 0.1 μmol/L after incubation for 72 h. In vivo, compared with the control group, the average tumor volume was reduced in both the 9NC and 9NC-LP group (P<0.05) , and the average animal body weight also decreased in both the 9NC and 9NC-LP group (P<0.05). There was no significant difference among the control group, free liposomes group, and DMSO group. The lights inhibition rates of tumor growth in the 9NC-LP(2.5 mg/kg),9NC-LP(1.5 mg/kg),and 9NC(1.5 mg/kg)groups were 87.02%, 51.57%and 35.47%, respectively. In the 9NC-LP(2.5 mg/kg)group, >50% of animals died 14 days after drug administration. Conclusion 9NC and 9NC-LP can inhibit HepG2 cell growth via cell cycle arrest and apoptosis induction. 9NC-LP has a more potent anti-tumor effect and fewer side effects in vivo,which means 9NC-LP is a promising compound for cancer therapy via intravenous administration.