Experimental Study Of Tetramethylpyrazine On Anti-angiogenesis Of Colorectal Cancer Sw620 Xenografts In Nude And The Inhibitory Tumor Mechanism

ObjectiveTo Investigate the Inhibition affects of tetramethylpyrazine on angiogenesis of xenografts in nude mice, and further explore the possible mechanism of antitumor.MethodsEstablished the model of colorectal cancer sw620 xenograft in nude mice, 30 tumor-bearing nude mice were randomly divided into five groups:NS negative control group,the low(50mg/kg), middle(100mg/kg) and high(200mg/kg) dose of tetramethylpyrazine group, endostar positive control group(20mg/kg). Measuring tumor volume and weight after administration. Observed pathological changes in tumors. Immunohistochemistry and Western blotting was used to detect tumor tissue expression of CD34, VEGF, HIF-1α.ResultsThe affects of TMP on the volume of tumor growth: high dose of TMP group and endostar group volume of tumor growth was significantly lower than the saline group (P<0.01), middle dose of TMP group was also below normal saline group (P<0.05), tumor volume of the low dose of TMP group compared with the saline group had no significant difference. The affects of TMP on the tumor weight and inhibition rate: middle high dose group of TMP group and endostar group degree of tumor weight was lower than the saline group, the low dose of TMP group compared with the saline group had no significant difference . The affects of TMP on the microvessel density : saline negative control group was significantly higher than that of high dose of TMP group and positive control endostar group (P<0.01), slightly higher than the middle dose of TMP group (P <0.05),low dose of TMP group compared with the saline group had no significant difference.The affects of TMP on sw620 tumor HIF-1αand VEGF expression: HIF-1αand VEGF expression of the middle dose of TMP group were both inhibited (P<0.05). HIF-1αand VEGF expression of the high dose of TMP group were inhibited significantly (P<0.01).ConclusionsTetramethylpyrazine can inhibit colorectal cancer sw620 xenografts growth in nude mice, the mechanism of affect may be related to improve the blood circulation drugs on tumor blood flow changes, elimination of microcirculation, improve the status of tumor tissue hypoxia, so that the decreased expression of HIF-1α, VEGF, thereby reducing angiogenesis, restore the normal microen- vironment of the body, and the purpose of ultimately inhibit tumor.