[Screening and their anti-tumor activity of antisense oligodeoxynucleotides targeting KDR mRNA in breast cancer MCF-7 cells].
OBJECTIVE
To screen the antisense oligodeoxynucleotides (asONs) which could hybridize with KDR (kinase insert domain-containing receptor) mRNA in an effective and specific way and to explore their anti-tumor effects on breast cancer MCF-7 cell line in vitro.


METHODS
The asONs were firstly selected using oligodeoxynucleotides library hybridization or computer prediction, then their hybridization ability with KDR mRNA was further tested with oligonucleotide microarray. The asONs with strong hybridization intensity were selected. Their inhibitory effects on MCF-7 cells proliferation and KDR expression were assayed by MTT, RT-PCR and Western blotting assay, respectively.


RESULTS
In 13 asONs selected with oligodeoxynucleotides library hybridization, 8 (8/13, 61.5%) showed strong hybridization signals, while such was only 1 in 17 asONs designed by computer prediction. 9 asONs with strong hybridization intensity were selected and synthesized with phosphorothioated modification. All these asONs inhibited the MCF-7 cells proliferation in a dose-dependent manner, in which asON4 and asON7 screened by oligodeoxynucleotides library in combination with oligonucleotide microarray were the most effective, with inhibitory rates of 51.6% and 62.2% at 0.8 micromol/L, respectively. The KDR expression at mRNA and protein levels was reduced by both the two asONs, in a dose-dependent manner.


CONCLUSIONS
asONs screened by oligodeoxynucleotides library hybridization are well consistent with that chosen with oligonucleotide microarray. The combination of oligodeoxynucleotides library with oligonucleotide microarray is an effective approach of asONs screening. The asONs targeting KDR mRNA showed prominent anti-tumor activity on breast cancer MCF-7 cells.
Zheng
Su-jun
SJ
Institute of Radiation Medicine, Academy of Military Medical Sciences, Beijing 100850, China.
Lin
Ru-xian
RX
Xia
Yun
Y
Bo
Xiao-chen
XC
Ren
Hong
H
Zhong
Sen
S
Wang
Sheng-qi
SQ
D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D015723:Gene Library; D006801:Humans; D017403:In Situ Hybridization; D020319:Oligodeoxyribonucleotides, Antisense / Q000235:genetics / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D014162:Transfection; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000096:biosynthesis* / Q000235:genetics
D020319:Oligodeoxyribonucleotides, Antisense; D012333:RNA, Messenger; D040301:Vascular Endothelial Growth Factor Receptor-2