摘要
目的研究新构建的含人乳腺癌DF3启动子和白喉毒素A片段的重组表达载体PGL3-DF3-DTA对裸鼠人乳腺癌移植瘤的特异性杀伤作用。方法建立人乳腺癌移植瘤裸鼠动物模型,将4周龄裸鼠36只随机分为实验组、空载体组、空白对照组、阴性对照组4组,每组9只。将DF3阳性和阴性的人乳腺癌细胞MCF-7和MDA-MB-231分别接种于相应的裸鼠皮下。待成瘤后,将重组表达载体PGL3-DF3-DTA和PGL3-DF3多次、多位点注射入相应裸鼠移植瘤内。连续测量瘤体大小,计算瘤体体积。在不同时间点分批处死部分动物,行形态学观察、检测肿瘤细胞的凋亡,检测Ki-67,Bax及Bcl-2蛋白的表达。结果裸鼠人乳腺癌动物模型建立成功,经重组表达载体PGL3-DF3-DTA作用后的人乳腺癌细胞出现明显的凋亡现象,Ki-67及Bcl-2基因表达水平降低,Bax基因表达水平升高。结论重组表达载体PGL3-DF3-DTA能对DF3阳性的乳腺癌细胞产生特异性杀伤作用。
Objective To study the specific killing effect of recombinant expression vector containing human breast cancer DF3 promotor and diphtheria toxin A fragment on human breast cancer cells implanted in vivo. Methods To establish human breast cancer xenograft in nude mice, thirty-six nude mice were divided into four groups at random, nine animals in each group. Human breast cancer cells of DF3 positive and negative （MCF-7 and MDA-MB-231 ）were inoculated into corresponding animals respectively. Recombinant expression vector PGL3-DF3-DTA and PGL3-DF3 were inoculated into corresponding tumor after if developed in the animals. The tumor weight was measured and calculated continually. The animals were killed at different time periods. The morphological changes were observed. The apoptosis index of cells was evaluated by in-situ TUNEL. Immunocytochemical methods were used to detect the expression of Ki-67, Bax and Bcl-2 protein. Results Human breast cancer xenograft were established in nude mice successfully. The human breast cancer cells treated by PGL3-DF3-DTA showed a typical apoptosis morphology and TUNEL detection analysis revealed the apoptosis index of the experimental groups was significantly enhanced, which was associated with time and dosage. The expression of Ki-67 and Bcl-2 were downregulated, and the expression of Bax was elevated. Conclusions Recombinant expression vector PGL3-DF3-DTA could produce specific killing effect on DF3 positive human breast cancer cell line.
出处
《中国普通外科杂志》
CAS
CSCD
2007年第1期73-77,共5页
China Journal of General Surgery
基金
湖北省卫生厅科研基金资助项目(NX200501)
