[Effects of siRNA targeted to survivin in suppressing proliferation and inducing apoptosis in breast cancer MCF-7 cells].
OBJECTIVE
Blocking the expression of survivin with RNA interference techniques, the effects of suppressing proliferation and inducing apoptosis of breast cancer MCF-7 cells were investigated.


METHODS
A siRNA eukaryotic expression vector against survivin was constructed and transfected into breast cancer MCF-7 cells with lipofectamine 2000. The changes of survivin expression were detected by semi-quantitive RT-PCR and immunohistochemistry. The effect of suppressing proliferation of MCF-7 cell was detected by MTT assay. The effect of inducing MCF-7 cell apoptosis was detected by TUNEL assay.


RESULTS
The sequence-specific siRNA can efficiently block the expression of survivin both at mRNA and protein levels. The expression inhibition rate was 64.9% at mRNA level detected by semi-quantitive RT-PCR and 79.7% at protein level detected by immunohistochemistry. Blocking the expression of survivin can suppress proliferation of MCF-7 cells significantly. At 24 and 48 h after the cells were reseeded, the proliferation inhibition rates were 31.6% and 33.0%, respectively. At 24 h after transfection, apoptosis was induced in 12.9% of the cells as detected by TUNEL assay.


CONCLUSIONS
Blocking the expression of survivin with RNA interference technology can significantly suppress proliferation of MCF-7 cells and induce apoptosis to a certain degree. RNAi targeted to survivin has a potential value in gene therapy of breast cancer.
Guan
Hai-tao
HT
Department of Oncologic Surgery, Second Affiliated Hospital of Xi'an Jiaotong University Medical College, Xi'an 710004, China. guanhaitao@csco.org.cn
Xue
Xing-huan
XH
Wang
Xi-jing
XJ
Li
Ang
A
Qin
Zhao-yin
ZY
D017209:Apoptosis; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D034622:RNA Interference; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D000077022:Survivin; D014162:Transfection
C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D000077022:Survivin