[Inhibitory effect of antisense oligodeoxynucleotides targeting HER-2 mRNA on growth of breast cancer: experiment in vivo with mice].
OBJECTIVE
To investigate the inhibitory effect of antisense oligodeoxynucleotides targeting HER-2 mRNA on growth of breast cancer.


METHODS
Human breast cancer cells of the line SK-BR-3 that overexpresses HER-2 were injected subcutaneously into BALB/c nude mice. Seven to ten days after tumors were collected and made into homogenate. Antisense oligodeoxynucleotide HA6722 targeting HER-2 mRNA and its control sequence Scramble were synthesized. Forty-nine BALB/c nude mice were injected with homogenate of SK-BR-3 cells and then randomly divided into 7 equal groups: Group 1, injected intravenously with docetaxel (TXT) 7.5 mg.kg(-1).d(-1) once a week twice; Group 2, injected intravenously with TXT 15 mg.kg(-1).d(-1) once a week twice; Group 3, injected intravenously with TXT 7.5 mg.kg(-1).d(-1) once a week twice + HA6722 5 mg.kg(-1).d(-1) for 12 days; Group 4, injected intravenously with HA6722 5 mg.kg(-1).d(-1) for 12 days; Group 5, injected intravenously with TXT 7.5 mg.kg(-1).d(-1) once a week twice + Scramble6722 5 mg.kg(-1).d(-1) for 12 days; and Group 7, injected with normal saline. After the drug administration the mice were observed for additional 3-4 weeks to measure the size of tumor every other day. Then the mice were killed and the tumors were taken out to be examined. The inhibition rate was calculated.


RESULTS
The inhibition rate of tumor in Group 3 was 88.3%, not significantly different from that in Group 2 (88.7%, P > 0.05). The inhibition rate in Group 4 was 76.3%. The inhibition rates of tumor of Groups 2, 3, and 4 were all significantly higher than that in Group 7. However, the inhibition rate of tumor of Group 6 was not significantly different from that in Group 7.


CONCLUSIONS
Antisense oligodeoxynucleotides targeting HER-2 mRNA inhibits the growth of breast cancer in a sequence specific and dose-dependent manner.
Sun
Jun-zhong
JZ
No. 304 Clinical Department, General Hospital of Chinese People's Liberation Army, Beijing 100039, China.
Song
Hai-feng
HF
Li
Liu-shu
LS
Song
San-tai
ST
Zhu
Jian-hua
JH
Zhao
Hui
H