Activation of microbubbles by short-pulsed ultrasound enhances the cytotoxic effect of cis-diamminedichloroplatinum (II) in a canine thyroid adenocarcinoma cell line in vitro.

Ultrasound targeted microbubble destruction has succeeded in delivering drugs and genes. This study was designed to explore characteristics of ultrasound targeted microbubble destruction using short-pulsed diagnostic ultrasound. Canine thyroid adenocarcinoma cells were exposed to short-pulsed diagnostic ultrasound in the presence of cis-diamminedichloroplatinum (II) (cisplatin) and ultrasound contrast agent Sonazoid(®) microbubbles. The cytotoxic effect of cisplatin was enhanced by short-pulsed diagnostic ultrasound and microbubbles. Incubation time with microbubbles influenced the cytotoxic effect of cisplatin. However, exposure duration did not affect the cytotoxic effect of cisplatin. Therefore, short-pulsed diagnostic ultrasound may activate microbubbles near cells and deliver cisplatin into cells. In addition, activation of microbubbles may be concluded in a short time. Our results suggest that short exposure duration could be potentially sufficient to induce efficient drug delivery by ultrasound targeted microbubble destruction using short-pulsed diagnostic ultrasound.