RESUMO
Objective:To observe the inhibitory effects of Huangqi Jiedu Decoction on lung metastasis of breast cancer in nude mice; To explore the mechanism of intervening epithelial mesenchymal transformation (EMT) induced by Wnt/β-catenin signaling pathway.Methods:Totally 30 nude mice were divided into model group, adriamycin group and Huangqi Jiedu Decoction low-, medium-, and high-dosage groups according to random number table method. Each group was injected subcutaneously with mouse breast cancer 4T1 cells to construct tumor - bearing nude mice model. Huangqi Jiedu Decoction low-, medium- and high-dosage groups were intragastrically administrated with Huangqi Jiedu Decoction 17.82, 35.64 and 71.28 g/kg; adriamycin group was injected intraperitoneally adriamycin 0.05 g/kg; model group was intragastrically administrated with normal saline of the same volume for 21 d. Tumor volume was measured at 9, 15, and 21 days after modeling. After the end of administration, the tumor tissue was separated, the tumor weight was measured, and the tumor inhibition rate was calculated. The lung tissue was Isolated,, the number of lung metastatic nodules and the inhibition rate of lung metastasis was counted. HE staining was used to observe the tissue morphology and evaluate the effectiveness of the model. The protein expressions of β-catenin, E-Cadherin and Vimentin in lung tissue were detected by Western Blot. The mRNA levels of β-catenin, E-Cadherin and Vimentin in lung tissue were detected by real-time fluorescent quantitative PCR.Results:Compared with the model group, the tumor volume and mass of Huangqi Jiedu Decoction low-, medium- and high-dosage groups decreased ( P<0.01); the number of pulmonary metastasis nodules in Huangqi Jiedu Decoction high-dosage group significantly decreased ( P<0.01); the mRNA and protein expressions of β-catenin and Vimentinm decreased in the Huangqi Jiedu Decoction low-, medium- and high-dosage groups ( P<0.01), and the protein and mRNA expressions of E-Cadherin increased in the Huangqi Jiedu Decoction high-dosage group ( P<0.01). Conclusion:Huangqi Jiedu Decoction can effectively inhibit the growth and lung metastasis of breast cancer transplanted tumor, and the mechanism may be to down-regulate the expression of key molecules in the Wnt/β-catanin signaling pathway, thereby inhibiting the EMT process, so as to inhibit the lung metastasis of breast cancer.