Antitumor Proliferation and Related Mechanism of Ultrasound Irradiation Combined with Safflower Yellow

Abstract

Ultrasound irradiation is now the best method for evaluating benign and malignant tumor nodules. Chemotherapy has always played an important role in the treatment of malignant tumors. With the large-scale application of chemotherapy drugs, the problem of multidrug resistance of tumors has become more and more prominent, which has become one of the difficulties in tumor chemotherapy. This study mainly explores the antitumor proliferation and related mechanisms of ultrasound irradiation combined with safflower yellow. The breast cancer cell line 4T1 derived from BALB/c mice was selected. BALB/c is an albino laboratory mouse, which, like many commonly used sublines, originated from Mus musculus. BALB/c mice have been bred for more than 200 generations in research institutions around the world and are widely used in animal experiments in immunology and physiology. When the cell proliferation reached 80%–90% of the bottom area of the culture flask, it was resuspended, passaged, frozen, and resuscitated according to experimental needs. The 4T1 breast cancer cell line was cultured by conventional methods. 4T1 breast cancer cells in the logarithmic proliferation phase were collected. After 0.25% was digested with pancreatin, it was washed twice with PBS to adjust the concentration to 1 × 107/mL. A 0.1 mL tumor cell suspension was subcutaneously inoculated on the edge of the mouse chest, thereby establishing a breast cancer model of BALB/c mice. After 6-15 days, the tumor volume grew rapidly and became larger. When the length of the tumor is 2.5 × 2.5, the modeling is successful. Ultrasound-targeted microbubble destruction technology, as a novel drug delivery method with high efficiency and low toxicity, can form transient pores (sonoporation effect) on the cell surface, widen the intercellular space, and increase the membrane permeability, and thus effectively. The transport of drugs, genes, proteins, etc., is promoted to target organs and tissues. Tumor-forming mice were randomly divided into the following four groups: control group, safflower yellow group, ultrasound irradiation group, and ultrasound irradiation combined with safflower yellow group. From the second day of inoculation to the end of the experiment, the body weight of the mice successfully inoculated with 4T1 cells was measured every day; from the 5th day, tumors in each group were calculated body volume and tumor inhibition rate (TIR) of each group. The combined treatment group has a higher tumor inhibition rate than the ultrasound irradiation group, and the difference is statistically significant ( $P$  < 0.05). Ultrasound irradiation combined with safflower yellow pigment can effectively inhibit tumor proliferation, maintain, or even improve the efficacy of chemotherapy, thereby improving the patient’s tolerance to chemotherapy.