[Effect of microRNA-mediated p65 gene silencing on the proliferation and apoptosis of human breast cancer MDA-MB-231 cells].
OBJECTIVE
To explore the effect of microRNA (miRNA)-mediated p65 gene knockdown on the proliferation and apoptosis of human breast cancer MDA-MB-231 cells.


METHODS
p65-targeted miRNA plasmid was constructed and transfected into MDA-MB-231 cells via lipofectamine(TM)2000. The expression of p65 gene in the transfected cells at the mRNA and protein levels were detected by RT-PCR and Western blotting, respectively. The cell proliferation and apoptosis were measured by MTT assay and flow cytometry (FCM), respectively. The expressions of apoptosis-related proteins were detected by Western blotting in the transfected cells.


RESULTS
Compared with the negative control group, the expressions of p65 mRNA and protein in p65miRNA-trasnfected cells were significantly down-regulated (P<0.05). MTT assay showed significantly lowered viability of MDA-MB-231 cells after the transfection (P<0.05). FCM showed an increased cell apoptosis rate in p65miRNA group compared with that in the negative control group (P<0.05). Caspase-3 and PARP were both cleaved into their active forms and the expression of these active forms was increased in p65miRNA group.


CONCLUSIONS
The miRNA targeting p65 gene can inhibit the proliferation and induce apoptosis of breast cancer cells, and p65 gene might become a new target in gene therapy for human breast cancer.
Department of Immunology, Fourth Hospital of Hebei Medical University, Shijiazhuang, China. wangling1981@yahoo.com.cn
Ling
L
Wang
Bao-en
BE
Shan
Mei-xiang
MX
Sang
Yi-shui
YS
Lian
Bin
B
Wang
Chun-yan
CY
Ding
D017209:Apoptosis / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051996:Transcription Factor RelA / Q000235:genetics* / Q000378:metabolism; D014162:Transfection
D035683:MicroRNAs; C498143:RELA protein, human; D012333:RNA, Messenger; D051996:Transcription Factor RelA