靶向HER-2 mRNA反义寡核苷酸抗乳腺癌增殖的体内研究

目的观察以HER-2mRNA为靶点的反义寡核苷酸HA6722体内抗乳腺癌的作用及其与细胞毒药物多西紫杉醇联合应用时抗肿瘤活性的变化。方法以SK-BR-3乳腺癌细胞株为移植实验细胞株,以BALB/C裸鼠为移植动物,建立HER-2过表达乳腺癌动物模型,观察不同剂量反义寡核苷酸HA6722及其对照序列单用或/和细胞毒药物多西紫杉醇联合应用时的抗肿瘤活性,并设空白对照组。结果在5mg·kg-1·d-1的剂量下单药反义寡核苷酸HA6722连续多次注射(1次/d,×12)可对乳腺癌的体内生长具有显著的抑制作用,抑瘤率达76·3%;联合应用多西紫杉醇时抗乳腺癌增殖作用明显加强,中等剂量HA6722(5mg·kg-1·d-1)联合多西紫杉醇(7·5mg·kg-1·d-1)与高剂量多西紫杉醇(15mg·kg-1·d-1)单独注射具有可比拟的抑瘤活性,两组抑瘤率分别为88·3%和88·7%(P>0·05);而中剂量的Scramble6722+多西紫杉醇(7·5mg·kg-1·d-1)则未见抗肿瘤活性有进一步的增强(P>0·05)。结论中等剂量的HA6722与多西紫杉醇联合应用,可以明显增强后者的抗肿瘤活性,其抗瘤活性可与高剂量的多西紫杉醇相比拟。

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. CONCLUSION: Antisense oligodeoxynucleotides targeting HER-2 mRNA inhibits the growth of breast cancer in a sequence specific and dose-dependent manner.