[Inhibitory effect of cationic liposome-mediated antisense c-myb oligonucleotide on the growth of glioma].

Objective: To aim at demonstrating whether cationic liposome-mediated antisense c-myb oligonucleotide(LipoAON) can inhibit the growth of C6 glioma by intravenous injection.

Methods: Intracerebral C6 glioma cells were implanted into the left caudal nucleus of forty-eight male Wistar rats. There were four groups: LipoAON(n = 12), antisense c-myb oligonucleotide (AON; n = 12), cationic liposome (Lipo; n = 12), and normal saline (NS; n = 12). Six days after tumor implantation, the above-mentioned drugs were injected into the right femoral veins of the rats respectively. Two days later, the same drugs were injected into the left femoral veins. The appetite, motor and weight of every animal were closely observed during the whole experiment. Six rats of each group were respectively killed 4 days and 10 days after the end of administration. The weight change, pathologic examination and immunohistochemical analysis of c-myb expression of the tumor were completed.

Results: In LipoAON group, the growth of the tumors was significantly inhibited in a short time after treatment and c-myb expression was down-regulated. But in the AON group and Lipo group, the growth of the tumors was not inhibited and c-myb expression was not down-regulated, compared with that in NS group. The inhibitory effect of LipoAON on the tumors rapidly declined with time and c-myb expression was again up-regulated.

Conclusion: 1. Cationic liposome (LipofectAMINE) as transfection vehicle makes c-myb easily penetrate BBTB and enter the tumor. The technique is simple, safe, highly effective for the transfection of c-mybAON; 2. LipoAON has marked inhibitory effect on the growth of C6 glioma. The AON technical method for inhibiting the expression of c-myb oncogene has a research perspective in the treatment of glioma; 3. The inhibitory effect of LipoAON on the growth of glioma declines with time. The question about how to make c-myb AON have highly effective, sustained and stable expression in the tumor still requires further research.