Effect of Wumei Decoction on Core Signal Transduction Molecules of Microenvironment in Lung Metastasis of Breast Cancer

Abstract Background The influence of traditional Chinese medicine on the tumor microenvironment is one of the mechanisms of its overall conditioning effect. In this study, we observed the influence of Wumei decoction,a traditional Chinese medicine classic prescription, on the core signal transduction molecules of the lung metastasis microenvironment in the model of lung metastasis of breast cancer in mice. Methods A breast cancer animal model established by inoculating the second pair of mammary fat pads of SPF grade Balb/c female mice with mouse breast cancer 4T1 cells, stably transduced luciferase. Model animals were divided into drug observation group, drug control group and blank control group. Bioluminescence imaging technique in vivo was used to observe the growth and metastasis of breast cancer in situ and lung. The gene expression in the lung metastasis microenvironment of the drug observation group and the blank control group was detected by Agilent expression profiling chip, and the differential genes were screened. And STRING (https://string-db.org/) online analysis system was used to obtain the signal transduction network, and then the MCODE plug-in of Cytosacpe software was used to obtain the core signal transduction molecule. Finally, the expression of these signal transduction molecules was detected by RT-PCR, immunohistochemistry and Western blot. Results Observed from the bioluminescence imaging technology in vivo, the fluorescent area of the breast cancer in inoculation area of each group mice gradually increased over time, indicating that the tumor volume is continuously increasing. The fluorescence distribution of the blank control group was dispersed on the 30th day, which had exceeded the vicinity of the original inoculation focus, indicating that the tumor had obvious metastasis. However, the drug observation group and the drug control group did not show such obvious transfer. Transcription expression profile chip results showed that there were 123 differentially expressed genes in the drug observation group and the blank control group, of which 64 genes were up-regulated and 59 genes were down-regulated. The signal transduction network of the 123 differentially expressed genes was obtained. The core genes recommended were AGT, CCL20, CXCL9, CXCL10, and HTR1B. RT-PCR results showed that the expression of AGT, CCL20, CXCL9, CXCL10, and HTR1B in the drug observation group were reduced compared with the blank control group, and the difference was statistically significant, p < 0.01. The results of immunohistochemistry showed that the core genes of the drug observation group showed a low expression trend, and the difference of CCL20 and CXCL10 was statistically significant, p < 0.01. Western blotting results also showed that each core gene protein in the drug observation group, compared with the blank control group, showed a downward trend. The difference of AGT and CCL20 was statistically significant, p < 0.01, and the difference of CXCL10 was also statistically significant, p < 0.05 . Conclusions Wumei decoction,a traditional Chinese medicine classic prescription, can inhibit lung metastasis of breast cancer to a certain extent. Inhibiting the expression of AGT, CCL20, CXCL9, CXCL10, HTR1B and other core signal transduction molecules in the lung metastasis microenvironment is one of its mechanisms.