Radiosensitization Effect and Mechanism of Xuefu Zhuyutang on Transplanted Esophageal Carcinoma in Nude Mice / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo explore the radiosensitization and underlying mechanism of Xuefu Zhuyutang on subcutaneous transplanted esophageal carcinoma. MethodThe subcutaneous xenograft model of human esophageal carcinoma ECA-109 in nude mice was induced and the model mice were divided into a model group， an irradiation group， a Xuefu Zhuyutang group， and a combination group， with six nude mice in each group. After the intervention， the transplanted tumors were removed and weighed， and the tumor inhibition rate of each group was calculated according to the formula. The protein expression of hypoxia-inducible factor-1α （HIF-1α） and vascular endothelial growth factor A （VEGFA） was detected by immunohistochemistry （IHC）. The protein expression of mammalian target of rapamycin （mTOR）， HIF-1α， VEGFA， and vascular endothelial growth factor receptor 2 （VEGFR2） in transplanted tumors was detected by Western blot. The mRNA expression of mTOR， HIF-1α， and VEGFA in transplanted tumors was detected by real-time quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the conditions in the model group， the tumor weight decreased in the irradiation group and the Xuefu Zhuyutang group （P<0.05）， as well as the combination group （P<0.01）. Compared with the irradiation group， the combination group showed decreased tumor weight （P<0.05）， with tumor inhibition rate of 57.37%. Compared with the model group， the irradiation group， the Xuefu Zhuyutang group， and the combination group showed decreased protein expression of VEGFR2， p-mTOR， HIF-1α， and VEGFA （P<0.05， P<0.01） and reduced mRNA expression of mTOR， HIF-1α， and VEGFA （P<0.05， P<0.01）. Compared with the irradiation group， the combination group showed down-regulated protein expression of VEGFR2， p-mTOR， HIF-1α， and VEGFA （P<0.05， P<0.01） and reduced mRNA expression of mTOR， HIF-1α， and VEGFA （P<0.05， P<0.01）. ConclusionXuefu Zhuyutang can inhibit the growth of transplanted esophageal carcinoma ECA-109 in nude mice and shows an obvious radiosensitization effect in combination with radiotherapy. The mechanism may be related to the inhibition of the mTOR/HIF-1α/VEGFA signaling pathway to improve the hypoxic state of tumors.