Effect of doxorubicin and dual frequency (kHz-MHz) ultrasound waves exposure on the adenocarcinoma tumor growth

The effect of dual-frequency low-intensity ultrasound waves with repeated radiation on the breast tumor of Balb/c mice was investigated in the presence of a chemotherapy drug. In this study, the tumor-bearing mice were divided into five groups, two untreated groups (control and sham) and three experimental groups. Experimental groups were: a dual-frequency ultrasound (US) radiation (1 MHz and 150 kHz), a dual-frequency ultrasound with triple exposure (3 x 30 min), and one treated with a dose of doxorubicin alone. The results clearly demonstrate the significant effect of triple exposures of dual-frequency US [dual (REP)] on the increase of survival period of the studied mice. The dual (REP) group, with results similar to the drug-treated group, shows a significant difference from the sham group. With the repeated exposure of dual-frequency ultrasound radiation on mice carrying the chemotherapy drug, the T2 and T5 times (times needed by the tumor to grow to 2 and 5 times its initial volume, respectively) decrease. This decrease in T5 time is significant. It seems that repeated simultaneous exposure to low-intensity dual-frequency (1 MHz and 150 kHz) US can retard the growth of the adenocarcinoma tumor and increase the survival period in mice.