To investigate the therapeutic effect of ultrasound-mediated drug loaded microbubbles on ovarian cancer xenografts in nude mice.

Human ovarian cancer A2780 cells were used to establish subcutaneous metastasis model in nude mice. 40 mice were randomly divided into 4 groups and given different intervention methods. Group A: DDP solution and ultrasound microbubbles were injected into the tail artery of nude mice and then irradiated by ultrasound; Group B: DDP solution and ultrasound microbubbles were injected into the tail artery of nude mice without ultrasound irradiation; Group C: Normal saline was injected into the tail artery of nude mice and then was irradiated by ultrasound; Group D: No treatment was done. Nude mice in the four groups were treated once every 3 days for 6 times. After treatment, tumor volume, peak intensity (PI) of tumor site and pathological section were compared among the four groups. The analysis of variance was used for the comparison between the groups, SNK method was used for the further pair comparison, and t test was used for the comparison before and after treatment within the group.

Compared with before treatment, the tumor volume of group A was significantly reduced after treatment (t=-7.642, P < 0.01), and that of groups B, C and D was significantly increased after treatment (t=-7.841, -21.052, -10.051, P < 0.01). After treatment, there was statistically significant difference in tumor volume among the four groups (F=13.219, P < 0.01), and the tumor volume of group A was significantly smaller than that of the other groups (P < 0.01). Compared with before treatment, PI of ROI of tumor site decreased significantly in group A (t=-11.746, P < 0.01), while there was no significant change in PI of ROI of tumor site in groups B, C and D (t=1.173, -1.351, -2.014, P > 0.05). After treatment, there was statistically significant difference in PI of ROI of tumor site among the 4 groups (F=61.101, P < 0.01), and the PI of ROI of tumor site in group A was significantly lower than that in the other groups (P < 0.01). The pathological results showed that the necrosis degree of tumor cells in group A and B was obvious, and the necrosis degree of tumor cell in group A was more obvious than that in group B.

Ultrasound mediated drug loaded microbubbles can improve the drug concentration at tumor site, avoid the destruction of external environment, maintain the original metabolic properties of drugs, and achieve the goal of drug targeted release and precise treatment. It is possible to provide a new adjuvant chemotherapy for elderly patients with ovarian cancer.