Chutan-Jiedu decoction reverses resistance of lung cancer to gefitinib by processing EMT

AIM: To investigate the mechanism of Chutan-Jiedu decoction (CJD) reversing the resistance of lung cancer to gefitinib via epithelial-mesenchymal transition (EMT) pathway.METHODS: BALB/c nude mice (n=60) were selected to establish lung cancer xenograft model with human lung adenocarcinoma drug-resistant cell line H1975, which were randomly divided into 6 groups (10 mice per group):model group, gefitinib (0.04 g/kg) group, low-dose (13.52 g/kg) CJD group, middle-dose (27.04 g/kg) CJD group, high-dose (54.08 g/kg) CJD group, and combined medication group (27.04 g/kg CJD+0.04 g/kg gefitinib). The mice in each group were treated for 2 weeks before the tumor size and tumor weight were detected for the calculation of the tumor inhibitory rate. The mRNA and protein expression levels of E-cadherin, Snail and vimentin were determined by immunohistochemistry, Western blot and real-time PCR.RESULTS: Compared with model group and gefitinib group, the tumor size and the tumor weight in middle-dose CJD group, high-dose CJD group and combined medication group were decreased significantly (P<0.05). The results of immunohistochemistry, Western blot and real-time PCR showed that the expression of E-cadherin at mRNA and protein levels was increased significantly, while the expression of Snail and vimentin at mRNA and protein levels was decreased significantly (P<0.05).CONCLUSION: The growth of lung adenocarcinoma H1975 xenografts in nude mice is inhibited by CJD. In addition, the resistance of lung cancer to gefitinib is reversed. The mechanism may be related to the regulation of EMT-related protein expression.