Abstract: Objective To study the therapeutic effect of intranasal administration of temozolomide (TMZ) for brain-targeting
delivery in a rat model bearing orthotopic C6 glioma xenografts. Methods Forty Wistar rat bearing brain C6 glioma xenograft
were randomly divided into 4 groups and treated with physiological saline solution or with TMZ by intravenous injection,
gavage or intranasal administration. The tumor size, rat survival time and pathological changes were observed in each group.
Results Magnetic resonance imaging showed a significantly reduced volume of glioma in intranasal TMZ group compared
with that in the control, intraveneous TMZ injection group and TMZ gavage groups (12.45±2.49 mm3 vs 60.16±4.12, 33.17±3.56,
and 35.16±4.36 mm3, respectively, P<0.05). The median survival time of the C6 glioma-bearing rats was also significantly longer
in intranasal TMZ group than in the other 3 groups (31.0 days vs 20, 19, and 21.5 days, respectively, P<0.05). In the glioma
xenografts, PCNA expression was the lowest and tumor cell apoptosis rate the highest in intranasal TMZ group. Conclusion
Intranasal TMZ administration can suppress the growth of C6 glioma in rats and may serve as an effective strategy for glioma
treatment.