Investigation of the expression of P53 gene in bystander cells after therapeutic ultrasound exposure

Abstract

Background: Bystander effect is defined as biological responses observed in cells that are not exposed to radiation directly but these radiation effects are induced through messages from irradiated cells. One of the non-invasive methods for cancer treatment is ultrasound waves. The therapeutic efficacy of ultrasound waveslike treatment with ionizing radiation can be altered by the bystander effect, so it is necessary to evaluate the bystander effect after ultrasound exposure. In this study, the effect of ultrasound exposure on the expression of P53 gene in neighboring cells has been investigated. Materials and Methods: The cells were divided into three groups: control (without treatment), target (under direct ultrasound exposure) and the bystander (no radiation, only receiving target cells culture media). In the target group, the cells were exposed to the ultrasound and after one hour their culture medium were transferred to the bystander group. Cell viability and the expression of P53 gene by using the MTT assay and Real-time PCR was analyzed. Results: The percentage of cell survival in the target group was reduced compared to the control group, but in the bystander group, this difference was not significant. The expression of P53 gene in the bystander group was statistically increased compared to the control group. Conclusion: The bystander effect is induced after ultrasound exposure and it can increase the level of P53 gene expression in bystander cells.

Keywords

• Ultrasound waves
• Bystander effect
• MTT assay
• Real-time PCR
• P53 gene