LINE-1ORF-1p对ERα阳性乳腺癌细胞的体外影响研究

In vitro effect of long interspersed nucleotide acids element-1 ORF-1p on estrogen receptorα of positive human breast cancer cells

目的探讨人反转座子长散在重复序列编码蛋白1(LINE-1 ORF-1p)对ERα阳性乳腺癌细胞ZR75-1生长的影响及可能机理。方法利用Lipofectin 2000将LINE-1 ORF-1的表达载体及其空载体,siRNA及其空载体转染进入ERα阳性乳腺癌细胞ZR75-1细胞。使用MTT法测定LINE-1 ORF-1p对ERα阳性乳腺癌细胞ZR75-1生长的影响;利用Luciferase检测LINE-1 ORF-1p对ERα转录活性的影响。结果 MTT法观察结果发现,LINE-1 Flag-ORF-1p能够显著促进ZR75-1细胞的生长(P=0.018)。LINE-1 ORF-1p siRNA表达载体能够抑制ZR75-1细胞的生长(P=0.022),其体外抑制率为E2-:25.51%,P=0.025,E2+:64.29%,P=0.021。LINE-1 Flag-ORF-1p能够升高ERα的转录活性(P=0.008)。LINE-1 ORF-1psiRNA表达载体能够降低ERα的转录活性(P=0.015),结论 LINE-1 ORF-1p能够通过升高ERα的转录活性,促进乳腺肿瘤细胞ZR75-1生长。

Objective To study the effect of long interspersed nucleotide acids element-1 （LINE-1） ORF-1p on proliferation of estrogen receptor α （ER α） positive human breast cancer ZR75-1 cells and its possible mechanism. Methods LINE-1 ORF-1 expression vector siRNA or empty vector, was transfected into ER α positive ZR75-1 cells with Lipofectin 2000. Effect of LINE-1 ORF-lp on proliferation of ER α positive ZR75-1 cells and transcriptional activity of ERα was detected by MTT and luciferase assay, respectively. Results MTT assay showed that LINE-1 Flag-ORF-lp promoted the proliferation of ERα positive ZR75-1 cells （P=0.018） while LINE-1 ORF-1p expression vector siRNA inhibited the proliferation of ZR75-1 cells （P=0.022） with an in vitro inhibition rate of 25.51% and 64.29% for E2- and E2＋, respectively （P〈0.05）. LINE-1 Flag-ORF-1 increased the transcriptional activity of ER α （P=0.05） while LINE-1 ORF-1p expression vector siRNA reduced the transcriptional activity of ER α （P=0.015）. Conclusion LINE-10RF-1p nromotes the proliferation of ZR75-1 cells bv increasing the transcription activitv of ERα.