桑黄多糖对肉瘤S180细胞体内外的抑瘤作用

摘要

目的:研究桑黄多糖对肉瘤S180细胞体内外的抑瘤作用.方法:选用对数生长期肉瘤S180细胞,加入0(空白对照)、2、4、8 mg/mL的桑黄多糖溶液,分别培养12、24、36、48 h,MTT法测定细胞体外增殖抑制率,荧光染色法观察细胞凋亡形态,流式细胞术检测细胞凋亡率.建立S180细胞荷瘤小鼠模型并随机分为对照组和桑黄多糖高、中、低剂量组(400、200、100 mg/kg),每组10只,每天ig相应药物1次,连续12 d;末次给药24 h后处死小鼠,称瘤质量,计算抑瘤率,免疫组化法检测肿瘤组织中抑癌基因PTEN与癌基因C-myc蛋白表达.结果:与空白对照比较,桑黄多糖能增高S180细胞的增殖抑制率,促进其凋亡率升高(P<0.05或P<0.01),且具有浓度与时间依赖性.与对照组比较,桑黄多糖各剂量组小鼠的抑瘤率明显升高(P<0.01),PTEN蛋白表达增强(P<0.05或P<0.01),C-myc蛋白表达减弱(P<0.05).结论:桑黄多糖具有体内外抑瘤作用,并能上调抑癌基因PTEN和下调癌基因C-myc的蛋白表达.%OBJECTIVE:To study the antitumor effect of phellinus linteus polysaccharide on sarcoma S180 cells in vivo and in vitro. METHODS:Sarcoma S180 cells in logarithmic growth period were selected,adding into 0(blank control),2,4,8 mg/mL phellinus linteus polysaccharide solution and respectively culturing for 12,24,36,48 h. The in vitro proliferation inhibition rate of cells was determined by MTT method;its apoptotic morphology was observed by fluorescence staining and cell apoptosis rate was detected by flow cytometry. S180 tumor-bearing mice models were established and randomly divided into control group,phellinus linteus polysaccharide high-dose,medium-dose,low-dose groups(400,200,100 mg/kg),10 in each group. Model mice were in-tragastrically administrated related medicined,once a day,for 12 d. Mice were executed after 24 h of last administration,tumor weight was determined,tumor inhibition rate was calculated. Immunohistochemistry was conducted to detect the tumor suppressor gene PTEN and oncogene C-myc protein expressions in tumor tissue. RESULTS:Compared with blank control group,phellinus linteus polysaccharide can increase the proliferation inhibition rate of S180 cells and induce the increase of apoptosis rate(P<0.05 or P<0.01),showing a concentration-time manner. Compared with control group,the tumor inhibition rates in phellinus linteus polysaccharide groups were obviously increased (P<0.01),PTEN protein expressions were strengthened (P<0.05 or P<0.01) and C-myc protein expressions were weakened (P<0.05). CONCLUSIONS:Phellinus linteus polysaccharide shows antitumor ef-fect in vivo and in vitro,which can up-regulate the PTEN,down-regulate C-myc protein expressions.