壳寡糖的抑瘤作用及其作用机制研究

Study on Anti-Tumor Effect of Chitooligosaccharides and Its Mechanism

研究不同浓度的壳寡糖(COS)对OS-RC-2肾转移瘤细胞的抑制作用及其作用机制。体外培养肾肿瘤细胞OSRC-2,MTT法、AO/EB染色和流式细胞仪检测COS对其增殖分化、凋亡和增殖周期的影响;建立小鼠OS-RC-2肾转移瘤模型,COS(50、100、300、500mg/kg)灌胃15d后取瘤块并计算抑瘤率;透射电镜观察细胞超微结构的变化;RT-PCR和免疫组化检测COS对肾转移瘤VEGFmRNA表达的影响。实验显示,100和300mg/L COS可明显抑制肾肿瘤细胞OXRC-2的增殖(F=69.21,q=11.32、19.35,P<0.05)并促进其凋亡(F=205.72,q=31.52、23.21,P<0.01),还可使细胞在G0/G1期比例明显增高,S期比例降低(x2=22.54,P<0.05)。100和300mg/kg的COS可有效抑制小鼠肿瘤的生长(F=148.39,q=25.05、15.10,P<0.05);并可使VEGFmRNA的表达明显减低(F=172.05,q=35.50、25.27,P<0.01)。镜下可见细胞出现多形性改变,核染色质边聚等。结果表明,COS可抑制OS-RC-2肾转移瘤的生长,其中100和300mg/kg剂量组抑瘤效果较佳。

In this study, we analyzed the anti-tumor effect of chitooligosaccharides （COS） at different concentrations on the renal carcinoma and its mechanism. Renal carcinoma OS-RC-2 was cultured in vitro. MTT assay, AO-EB staining and flow cytometry were used to evaluate the effect of COS at different concentrations on the proliferation, differentiation and cell cycle of renal carcinoma OS-RC-2 cells. The renal carcinoma OS-RC-2 cells were transplanted into mice to establish the tumor model. COS was administered by garage with different doses （50, 100, 300 and 500 mg/kg）. The tumor inhibitory rate was measured. Transmission electron microscopy （TEM） was used to analyze the ultra microstructural change of renal carcinoma OS-RC-2 cells before and after therapy. RT-PCR and immunohistochemistry were used to ana- lyze the VEGF expression in renal carcinoma OS-RC-2 cells. MTT revealed that 100 and 300 mg/L COS could inhibit the proliferation of renal carcinoma OS-RC-2 cells （F=69.21; q=11.32, 19.35; P〈0. 05）. AO-EB staining revealed that 100 mg/L and 300 mg/L COS could promote the apoptosis of renal carcinoma OS-RC-2 cells （F=205.72; q-=31.52, 23.21; P〈0.01）; 100 mg/L and 300 mg/L COS could stop the cell cycle of tumor cells in G0/G1 phase and out of S phase obviously （or2 =22. 54, P〈0.01） ; 100 mg/kg and 300 mg/kg COS could inhibit VEGF expression in the tumor obviously （F= 172.05; q = 35.50, 25.27; P〈0.01） and decrease the cellular volume and amount of mitochondria of renal carcinoma OS-RC- 2 cells. The cells appeared polymorphism change, chromatin edge clustering under the microscope and among others. In conclusion, COS could inhibit the growth of tumor most appropriately at 100 mg/kg and 300 mg/kg.