摘要目的 观察c-myc基因反义硫代寡核苷酸(antisense oligodeoxynucleotide,ASODN)和5-氟尿嘧啶(5-fluorouracil,5-FU)对HEPG-2肝癌细胞增殖及c-myc基因表达的抑制作用,探讨c-myc ASODN作为药物进行肝癌基因与药物综合治疗的可行性.方法 应用脂质体介导的c-myc反义硫代寡核苷酸和5-FU联合作用于HEPG-2肝癌细胞,MTT法检测细胞增殖状态,RT-PCR和免疫组织化学方法检测c-myc基因表达抑制情况,流式细胞仪进行细胞周期分析,细胞荧光染色及基因组电泳观察细胞凋亡情况.结果 c-myc ASODN转染HEPG-2肝癌细胞后,细胞生长受抑制,其抑制作用有时间性及剂量依赖性(P=0.02,P=0.01),增殖能力减弱,同时ASODN能在转录和翻译水平上抑制c-myc基因的表达;5-FU在10 μmol/L时可明显诱导肝癌细胞凋亡;将c-myc ASODN与5-FU联合应用,则表现出对细胞凋亡的协同诱导作用(P=0.01).结论 脂质体介导的c-myc ASODN及5-FU对c-myc基因的表达具有明显的抑制作用,能抑制肝癌细胞增殖.c-myc ASODN能够增加肝癌细胞对5-FU的敏感性.

abstractsObjective To study the inhibition effect of c-myc ASODN (antisense oligodeoxynucleotide) and 5-FU (5-fluorouracil) on the expression of c-myc gene and the proliferation of human hepatoma cells HEPG-2. Methods After treated by liposome mediated c-myc antisense phosphorothioate oligodeoxynucleotide (APSODN) and 5-FU, the growth inhibition rate was detected by MTT assay, the expression of c-myc mRNA was detected by RT-PCR and immunohistocehemical methods HEPG-2cells. The cell cycle was analyzed by flow cytometric analysis. The morphological changes were observed by fluorescence staining and cellular genome electrophoresis. Results After sealing c-myc gene with ASODN,the growth of cells was repressed and the effect was time-dependent and dose-dependent ( P = 0. 02 ). The ability of proliferation decreased, the expression of c-myc gene was inhibited on transcription and translation levels; 5-FU can induce apoptosis of hepatoma cells HEPG-2 dramatically with the dose of 10 μ mol/L, when treated by both c-myc ASODN and 5-FU, HEPG-2 cells was induced apoptosis in a cooperative style ( P =0. 01 ). Conclusions The liposome mediated c-myc (APSODN) and 5-FU can inhibit the proliferation of HEPG-2 cells by inhibiting the expression of c-myc gene and can induce apoptosis of hepatoma cells HEPG-2 in a cooperative style. c-myc ( APSODN ) can increase the sensitivity of 5-FU to hepatoma cells and decrease the effective concentration of 5-FU.