摘要
目的:观察阿霉素作为G-四联体配体对Tca8113细胞端粒酶活性、增殖及凋亡的影响,探讨G-四联体结构生物学功能。方法:通过TRAP法和改良TRAP-G4法,分析阿霉素对Tca8113细胞端粒酶介导的端粒延伸反应的影响。研究分2个实验组进行,用药组培养液含2.5μmol/L阿霉素,非用药组培养液加相应体积生理盐水,细胞培养1、3、5和7d后,利用TRAP法检测其端粒酶活性;流式细胞仪分析其细胞周期和凋亡率,并对2实验组间凋亡率进行t检验;Giemsa染色和SA-β-gal染色观察凋亡和衰老细胞。结果:TRAP和改良TRAP-G4检测表明,阿霉素通过诱导G4形成抑制Tca8113细胞端粒酶介导的端粒延伸反应。在2.5μmol/L阿霉素作用下,Tca8113细胞端粒酶活性在3d后出现降低;用药组细胞增殖受抑制,停滞于G0-G1期和S期;所有观察期内2实验组间细胞凋亡率差异有统计学意义(P<0.05);用药组出现衰老和凋亡细胞。结论:阿霉素诱导G-四联体形成,可抑制Tca8113细胞端粒酶活性,降低其增殖活性,促进衰老和凋亡发生。
PURPOSE： To observe the effects of adramycin as guanine-quadruplex ligand on telomerase activity, proliferation and apoptosis of Tca8113 cells by inducing telomere to form G-quadruplex structure, and to evaluate the biological functions of the structures. METHODS： The influence of adramycin on telomeric extension reaction mediated by telomerase of Tca8113 cells were analyzed by TRAP assay and modified TRAP assay. Two groups were adopted in this study , namely treated group containing 2.5μmol/L Adramycin in the medium and untreated one containing sodium saline. Tca8113 cells in the subsequent experiments were cultured for 1,3,5 and 7days. On indicated day, telomerase activity in Tca8113 cells was evaluated bv TRAP assay; the cell cycle and the apoptotic rates were analyzed by flow cytometry; the apoptotic rate differences between the two groups were analyzed with Student＇s t test; the senescent and apoptotic cells were observed after senescence-associated-β-galactosidase staining and Giemsa staining, respectively. RESULTS： The results of TRAP assay and modified TRAP assay demonstrated that Adramycin led to inhibition of telomeric extension reaction mediated by telomerase of TcaS113 cells by inducing formation of G-quadruplex structures. In the presence of Adramycin at 2.5μmol/L, telomerase activity of Tca8113 cells decreased after 3 days of treatment with adramycin ; cell proliferation of the treated groups was inhibited and the cell cycle arrested at phase G0-G1 and S; there was significant difference of apoptotic rates between the treated group and the untreated one on the indicated day （P〈0.05）; Senescent cells and apoptotic cells appeared in the treated groups. CONCLUSIONS： Adramycin＇s inducing telomere to form G- quadruplex structure lead to inhibition of telomerase activity in Tca8113 cells, decreasing of proliferative activity and occurrence of senescence and apoptosis.
出处
《中国口腔颌面外科杂志》
CAS
2005年第3期212-217,共6页
China Journal of Oral and Maxillofacial Surgery
基金
中国博士后基金(中博基2003033421)
