Abstract

  Background and Aim: Experiments have showed that the use of combined single or dual frequencies ultrasound irradiation in low-level intensity for treatment of cancer is effective . We investigated the antitumor effect of simultaneous low-intensity, 150 kHz ultrasound, in combination with the anticancer drug doxorubicin (DOX) on breast adenocarcinoma using murine model (Balb/c).

  Materials and Methods: Forty-four mice were used in this study. The tumor-bearing mice were divided into five groups, namely, control, sham, drug, drug+US and exposure to ultrasound alone . The administrated dose of DOX was 2 mg/per i.v, and the time of exposure was 30 minutes.

  Results: We showed that, after the injection of DOX, exposure to ultrasound at 150 kHz_con potentiates the effect of doxorubicin on the growth of adenocarcinoma tumors compared to control group by two folds. The tumor growth inhibition percent in the groups treated by ultrasound and doxorubicin showed an increase compared with the group treated with doxorubicin alone. The total tumor growth inhibition percent (days 3-21) in the drug alone, drug+150 kHz groups was 23(%), 55(%), respectively . There was also a significant difference between the drug-treated group and the drug+US groups in times needed for each tumor to reach 2 and 7 times its initial volume (T₂ and T₇).

  Conclusion: The co-administration of DOX and low-intensity ultrasound provided a more effective treatment than the drug alone in murine breast cancer. The combined treatment appeared to produce synergistic effects that are potentially useful in reducing the side effects of DOX by lowering the required effective dose of the drug while increasing the efficiency of the therapy as a whole.