RESUMO
ObjectiveTo investigate the effect of Guiqi Baizhu prescription （GQBZ） combined with oxaliplatin on the expression of epidermal growth factor receptor （EGFR） and vascular endothelial growth factor receptor-2 （VEGFR2） and angiogenesis in gastric cancer-bearing mice. MethodThe tumor-bearing model of gastric cancer was induced in Kunming mice. The mice were randomly divided into blank group， model group， oxaliplatin group （10 mg·kg-1）， and high- （17.68 g·kg-1）， medium- （8.84 g·kg-1）， and low-dose （4.42 g·kg-1） combination groups （GQBZ combined with oxaliplatin）. After the last administration， the transplanted tumor was collected and the tumor inhibition rate was calculated. Hematoxylin-eosin （HE） staining was used to observe the morphological changes of tumor tissues. Enzyme-linked immunosorbent assay （ELISA） was used to detect the serum content of epidermal growth factor （EGF）， interleukin-8 （IL-8）， and vascular endothelial growth factor （VEGF）. Western blot and immunohistochemistry （IHC） were used to detect the expression of EGFR， phosphorylated EGFR （p-EGFR）， VEGFR2， phosphorylated VEGFR2 （p-VEGFR2）， and platelet-endothelial cell adhesion molecule （CD31）. Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of EGFR and VEGFR2. ResultThe tumor weight in the drug intervention groups was significantly lower than that in the model group （P<0.01）. Compared with the oxaliplatin group， the high- and medium-dose combination groups showed reduced tumor weight （P<0.05， P<0.01）. The tumor cells in the model groups were high in cell density and regular in shape， and no clear tissue necrosis was seen. The tumor cell density in the drug intervention groups was reduced， and clear tissue necrosis and large-scale inflammatory cells were visible. Compared with the blank group， the model group and the drug intervention groups showed increased serum levels of EGF， VEGF， and IL-8 （P<0.05， P<0.01）. Compared with the model group， the drug intervention groups showed decreased serum levels of EGF， VEGF， and IL-8 （P<0.01）， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and declining mRNA expression of EGFR and VEGFR （P<0.01）. Compared with the oxaliplatin group， the high- and medium-dose combination groups showed decreased serum levels of EGF， VEGF， and IL-8 （P<0.05， P<0.01）， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and dwindled mRNA expression of EGFR and VEGFR2 （P<0.05， P<0.01）. The low-dose combination group showed decreased serum levels of EGF， VEGF， and IL-8， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and dwindled mRNA expression of EGFR and VEGFR2， but the difference was not statistically significant. ConclusionGQBZ combined with oxaliplatin can inhibit the growth and angiogenesis of tumor tissues in gastric cancer-bearing mice by affecting the expression of EGFR and VEGFR2.
