目的: 研究利用聚酰胺胺型树枝状分子(polyamidoaminedendrimer，PAMAMD)递送STAT3反义寡核苷酸(antisense oligodeoxynucleotide，asODN)抑制人肝癌细胞（SMMC7721）增殖的效应。方法: 第7代的聚酰胺胺型树枝状分子室温下与STAT3反义寡核苷酸混合制备树形分子与反义寡核苷酸的复合物(PAMAMasODN)，应用透射电镜观察复合物的形态结构，激光粒径仪测定复合纳米微粒的粒径。MTT法检测复合纳米微粒对肝癌细胞SMMC7721增殖的抑制作用，采用流式细胞术与TUNEL技术检测PAMAMasODN诱导SMMC7721细胞凋亡和细胞周期的变化，实时定量PCR分析PAMAMasODN作用后肝癌细胞STAT3 mRNA的表达水平。结果: 成功制备的新型纳米复合微粒分散均匀、流动性好，其粒径约为85.45 nm。MTT检测结果表明，纳米复合微粒以时间和浓度依赖的方式抑制人肝癌细胞增殖，其最高抑制率达（68.9±3.0）%。流式细胞与TUNEL技术检测表明，PAMAMasODN可加强诱导肝癌细胞凋亡（P<0.01)，使细胞周期阻滞于G2/M期。实时定量PCR的结果表明， PAMAMasODN作用后肝癌细胞中STAT3 mRNA表达较asODN作用组降低了（54±2.1)%。结论:聚酰胺胺型树枝状分子能高效递送STAT3 asODN，可显著抑制肝癌细胞增殖和诱导细胞凋亡。

Objective: To explore the inhibitory effect of polyamidoamine dendrimer (PAMAMD) STAT3 antisense oligodeoxynucleotide complex (PAMAMasODN) against the proliferation of hepatocarcinoma cell line SMMC7721. Methods: The seventh generation of PAMAM was mixed with STAT3 asODN in room temperature to prepare a PAMAMasODN complex. The morphology of the complex was examined by transmission electron microscope (TEM); the mean diameter of the complex was evaluated using laser particle size analyzer; and its inhibitory effect on the proliferation of SMMC7721 cells was measured by MTT. Cell cycle, apoptosis, and STAT3 mRNA expression in SMMC7721 cells treated with PAMAMasODN were examined by FACS/TUNEL and realtime PCR, respectively. Results: The PAMAMasODN complex was successfully prepared, with even distribution, good fluidity, and a mean diameter of 85.45 nm. MTT assay showed that PAMAMasODN inhibited the proliferation of SMMC7721 cells in a time and concentrationdependent manner, with the highest inhibitory rate being (68.9±3.0)%. FCM and TUNEL assay showed that PAMAMasODN induced apoptosis of SMMC7721 cells and blocked cell cycle at G2/M phase. Realtime PCR showed that the expression of STAT3 mRNA in SMMC7721 cells was significantly decreased after treatment with PAMAMasODN.Conclusion:PAMAM dendrimer can efficiently deliver STAT3 asODN into SMMC7721 cells, significantly inhibit SMMC7721 cells proliferation, and induce apoptosis of hepatocarcinoma SMMC7721 cells.

上海科委专项基金资助项目 （No.0452nm009）