知识与财富的链接
目的 观察低氧下丹参酮ⅡA(Tan Ⅱ A)对人胃癌SGC7901细胞突变型p53表达的影响,及其与HIF-1α表达和凋亡的关系. 方法 用氯化钴(CoCl2)创建低氧模型,设常氧对照组、低氧对照组和低氧加不同浓度Tan Ⅱ A组.分别取0.5mg/L、1.0mg/L、2.0mg/L、5.0mg/L、10.0mg/L的Tan Ⅱ A干预低氧胃癌SGC7901细胞48h和72h后HOECHST染色法检测细胞凋亡.Tan Ⅱ A(0.5mg/L、2.0mg/L、10.0mg/L)干预低氧胃癌细胞48h后,免疫细胞化学二步法检测HIF-1α和突变型p53蛋白表达的变化. 结果 HOECHST染色法发现,低氧条件下,Tan Ⅱ A可呈时间、剂量依赖性地诱导胃癌SGC7901细胞凋亡(P<0.01),10.0mg/L TanⅡA作用细胞72h后,凋亡率达(40.70±1.55)%.免疫细胞化学法显示,Tan Ⅱ A呈剂量依赖性地抑制HIF-1α和突变型p53蛋白表达,且二者呈高度正相关(n=4,r=0.886,P<0.05). 结论 低氧条件下Tan Ⅱ A抑制人胃癌SGC7901细胞HIF-1α和突变型p53的表达,并诱导其凋亡,提示Tan Ⅱ A可能对防治低氧及p53突变导致的克隆选择及凋亡抵抗具有重要作用.
AbstractObjectiveThe effects of Tan ⅡA on the expression of mutant p53 (mt p53) and HIF-1α in gastric cancer SGC7901 cell under hypoxia and the correlation between expression of mt p53, HIF-1α and apoptosis were studied. MethodsThe model of hypoxia was established by CoCl2. There were three groups: normal control group, hypoxia control group, and hypoxia combined with different concentrations of Tan ⅡA group. After Tan ⅡA was added to the media with 0.5, 1.0, 2.0, 5.0 and 10.0mg/L respectively for 48 and 72h during hypoxia, the apoptosis of SGC7901 human gastric cancer cells was detected by HOECHST stain. After Tan ⅡA was added to the media with 0.5, 2.0 and 10.0mg/L respectively for 48h during hypoxia, the expression of HIF-1α and mt p53 protein was detected by immunocytochemical staining. ResultsThe results of HOECHST stain found that Tan ⅡA induced apoptosis of gastric cancer cells in a dose- and time-dependent manner under hypoxia(P＜0.01), and the apoptosis rate reached (40.70±1.55)% after treatment with 10.0 mg/L Tan ⅡA for 72h. The results of immunocytochemical staining revealed that the expression of HIF-1α and mt p53 protein was inhibited by Tan ⅡA in a dose-dependent manner under hypoxia. High positive correlation was found between the expression of HIF-1α and mt p53(n=4, r=0.886, P＜0.05). ConclusionTan ⅡA can inhibit the expression of HIF-1α and mt p53 protein, and induce the apoptosis of SGC7901 human gastric cancer cells under hypoxia, suggesting that Tan ⅡA might play an important role in fighting against hypoxia-and p53 mutation- induced clonal selection and apoptosis resistance of tumor.
