The Effect of Ultrasound Exposure in Combination with Gold Nanoparticles on Colonization of A375 and MCF-7 Bystander Cells

The biological response of cells that are not directly exposed to radiation, but are in the vicinity or the environment of irradiated cells, is known as the radiation bystander effect. In previous studies, the existence and mechanism of the bystander effect induced by ionizing radiation have been investigated. Recently, ultrasound therapy was inducted as a new method for treating some cancers. Therefore, it seems necessary to evaluate the ultrasound-induced bystander effect.

To investigate the ultrasound-induced bystander effect, A375 and MCF-7 cell lines were cultured in the target and bystander plates. The target plates included four groups of control (without intervention), ultrasound, gold nanoparticles, and simultaneous ultrasound treatment and gold nanoparticles. The four bystander groups received the culture medium of the target groups, respectively. MTT and colony forming units assays were </em>performed to investigate the ultrasound induced bystander effect.

The percentage of colonization in bystander groups receiving ultrasound without and with gold nanoparticles were significantly lower compared with the control group. However, the amount of colonization for the MCF-7 cell line was more than A375.

The results showed that the ultrasound-induced bystander effect was intensified in the presence of gold nanoparticles due to.