[Inhibition of proliferation in MCF-7 breast cancer cells by plasmid-based siRNA targeting to oncogene c-myc].
OBJECTIVE
To investigate the effects of plasmid-based siRNA targeting to oncogene c-myc on c-myc/ c-Myc expressions and cells proliferation in MCF-7 breast cancer cells.


METHODS
siRNA eukaryotic expression plasmid p-Mat01-1 targeting to the sequence 589-609 of oncogene c-myc and its mismatch plasmid p-Mis09-1 were constructed, and transiently transfected MCF-7 cells using Lipo2000. Semi-quantitative RT-PCR and Western blot were used to analyze the expressions of c-myc/c-Myc in MCF-7 cells, and cells proliferation was detected by MTT assay.


RESULTS
p-Mat01-1 inhibited the expressions of c-myc mRNA (24 h: P < 0.01) and c-Myc protein (5 d. P < 0.01) in MCF-7 cells as compared with pEGFP-C1 and p-Mis09-1 controls, and suppressed the proliferation of MCF-7 cells significantly (3 d: P < 0.05, 5, 7 d: P < 0. 01).


CONCLUSIONS
Plasmid-based siRNA targeting to oncogene c-myc could inhibit the expressions of c-myc/c-Myc in MCF-7 breast cancer cells efficiently, suggesting that the downregulation of c-myc/c-Myc could suppress the proliferation of MCF-7 cells in vitro.
Department of Immunology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
Chang-Hua
CH
Zhou
Xiao-Dong
XD
Peng
Jing
J
Wu
Ping
P
Zhang
Zong-Rong
ZR
Zhao
Da-Peng
DP
Wei
Chong-Jie
CJ
Zhang
D001483:Base Sequence; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection
D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D034741:RNA, Small Interfering