肽核酸对大肠癌细胞生长影响的实验研究

The Experimental Study on the Impact and Significance of Peptide Nucleic Acids on Colorectal Cancer Cell Growth

研究肽核酸（PNA）对大肠癌细胞端粒酶活性的抑制作用及其对大肠癌细胞生长的影响，探索大肠癌治疗新方法。（1）检测不同浓度PNA对大肠癌LS-174T细胞端粒酶活性的影响；（2）应用脂质体Lipfectamine^TM介导不同浓度PNA-DNA杂交混合物转染LS-174T细胞，观察细胞克隆生长抑制结果，确定PNA对细胞生长的最佳抑制剂量；（3）选用最佳抑制剂量PNA转染LS-174T细胞、Lipfectamine^TM组和空白对照组，并观察其克隆形成率、细胞形态及群体生长差异。结果显示：（1）不同浓度PNA对大肠癌细胞端粒酶活性均有抑制作用，且与PNA浓度呈正相关；（2）细胞克隆形成抑制实验中PNA对LS-174T细胞最佳抑制浓度为200nmol／L；（3）PNA实验组端粒酶活性明显低于脂质体组和空白对照组。结果表明，PNA抑制大肠癌细胞端粒酶活性对大肠癌LS-174T细胞生长具有明显抑制作用，为大肠癌早期诊断与治疗开辟新途径。

The objecitve of the experiment was to identify the inhibitory effect of peptide nucleic acids （PNA） on telomerase activity of colorectal cancer cells and the impact of PNA on colorectal cancer cell growth. In the experiment, the following 3 steps were included ： （1） to detect the effects of different concentrations of PNA on telomerase activity of LS-174T cell colorectal cancer; （2）to transfect LS-174T cells with different concentrations of PNA-DNA hybridism mixture which had been mediated by liposome lipfectamine^TM,and to observe the inhibition results of LS-174T cell clone growth so as to ascertain the optimal inhibitory concentration of PNA; （3）to transfect LS-174T cells,the LipfectamineTM group and the blank controlled group with the most optimal inhibitory dose of PNA, and to observe the cloning efficiency, the cancer cells＇ morphology and the group growth diversity. As results, （1）all the different concentrations of PNA could inhibit telomerase activity of LS-174T colorectal cancer cells, and the inhibitory action was positively correlated to the concentration of PNA; （2）the optimal inhibitory concentration of PNA on LS-1/4T ceils was 200 nmol/L in the cell clone inhibitory experiment; （3）the telomerase activity in the PNA experiment group was obviously lower than that in the Lipfectamine^TM group and the blank group. It is concluded that PNA has an outstanding inhibitory effect on LS-174T cells through inhibition of telomerase activity,which may pave a new path leading to the early diagnosis and treatment of colorectal cancers.