[siRNA against survivin coupling with epirubicin enhances to induce breast cancer cell MCF-7 to apoptosis].
OBJECTIVE
To use the sequence-specific siRNA knocking down the expressions of Survivin gene and inducing breast cancer MCF-7 cell line to apoptosis, and to couple the siRNA with Survivin for investigating the effects of MCF-7 cell induced to apoptosis and the chemotherapy sensitivity of breast cancer cell treated to epirubicin.


METHODS
The molecular cloning technique was applied to construct the eukaryotic expression vector of siRNA against Survivin, and lipofectamine 2000 was used to transfect MCF-7 cell. Survivin expressions were detected by semi-quantitive RT-PCR and immunohistochemical SABC methods. The effects of inducing MCF-7 cell apoptosis and enhanced chemotherapy sensitivity to epirubicin were assessed by TUNEL method.


RESULTS
The sequence-specific siRNA can, effectively and specifically, knock the expressions of Survivin gene down at both mRNA and protein levels, in which the expression inhibition rates were 64.91 and 79.72% respectively. After 48 h, 8.75% cells transfected with siRNA expression vector were induced to apoptosis; Coupling siRNA against Survivin with epirubicin can induce the cell apoptosis rate up to 24.21%.


CONCLUSIONS
In the study, the siRNA against Survivin can, effectively and specifically, decrease the expressions of Survivin gene in MCF-7 cell; blocking the expressions of Survivin can, in certain degree, induce MCF-7 cell to apoptosis and enhance cell chemotherapy sensitivity to epirubicin significantly; Survivin RNAi has a great potential value in the gene therapy of breast cancer.
Guan
Hai-Tao
HT
Department of Oncosurgery, the Second Affiliated Hospital of Xi'an Jiaotong University Medical College, Xi'an 710004, China.
Xue
Xing-Huan
XH
Wang
Xi-Jing
XJ
Li
Ang
A
Qin
Zhao-yin
ZY
D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000473:pathology*; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D015251:Epirubicin / Q000494:pharmacology*; D005057:Eukaryotic Cells / Q000378:metabolism; D005260:Female; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D034741:RNA, Small Interfering / Q000096:biosynthesis / Q000235:genetics*; D000077022:Survivin
D000903:Antibiotics, Antineoplastic; 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; D015251:Epirubicin