Objective: This study aimed to explore ultrasound-guided injections of Ultrasound Contrast Agents (UCAs) and p53 gene for the treatment of rats with breast cancer.
Methods: With the construction of p53 expression vector and rat model with breast cancer, 160 rats that modeled successfully were randomly divided into 4 groups: p53 gene introduction group, p53 gene introduction+ultrasound irradiation group, p53 gene introduction+CUAs group and p53 gene introduction+CUAs+ultrasound irradiation group. With regular ultrasonography after p53 injection, the rats were killed after 14 d, and the tumors were separated and weighed to calculate the tumor inhibition rate. H and E staining was used to observe the tumor tissues. The expression of p53 in tumor tissues was detected by Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR), Western blotting and immunohistochemically staining, respectively.
Results: In the p53 gene introduction and p53 gene introduction+CUAs groups, the tumor volume of rats significantly increased, with uneven echoes and abundant blood-flow signals, the tumor cells with good growth and acidophilic cytoplasm, and p53 had low expression. In the p53 gene introduction +ultrasound irradiation group, the tumor volume of rats increased slowly, surrounded by blood-flow signals and necrotic tumor tissues, with a tumor inhibition rate of 36.30%, and the expression of p53 was higher than that in the p53 gene introduction and p53 gene introduction+CUAs groups. In the p53 gene introduction+CUAs+ultrasound irradiation group, the tumor volume of rats increased slightly, blood-flow signals significantly decreased, the tumor cells had extensive degeneration and necrosis with a tumor inhibition rate of 62.62%, and the expression of p53 was higher than that in other three groups.
Conclusion: Ultrasound irradiation after ultrasound-guided injections of UCAs and p53 gene could increase the expression of p53 gene, thus inhibit the growth of rat with breast cancer.