Background Studies have shown that the drug resistance of gastric cancer cells can be modulated by abnormal expression of microRNAs （miRNAs）.We investigated the role of miR-503 in the development of cisplatin resist...Background Studies have shown that the drug resistance of gastric cancer cells can be modulated by abnormal expression of microRNAs （miRNAs）.We investigated the role of miR-503 in the development of cisplatin resistance in human gastric cancer cell lines.Methods MiR-503 expression was measured by quantitative real-time PCR.MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide） and clonogenic assays were used to examine changes in cell viability and the drug resistance phenotype of cancer cells associated with upregulation or downregulation of the miRNA.A dual-luciferase activity assay was used to verify target genes of miR-503.Immunohistochemistry,Western blotting analysis,and a flow cytometric apoptosis assay were used to elucidate the mechanism by which miR-503 modulates drug resistance in cancer cells.Results MiR-503 was significantly downregulated in gastric cancer tissues and several gastric cancer cell lines.Additionally,downregulation of miR-503 in the cisplatin （DDP）-resistant gastric cancer cell line SGC7901/DDP was concurrent with the upregulation of insulin-like growth factor-1 receptor （IGF1R） and B-cell lymphoma 2 （BCL2） expression compared with the parental SGC7901 cell line.An in vitro drug sensitivity assay showed that overexpression of miR-503 sensitized SGC7901/DDP cells to cisplatin.The luciferase activity of reporters driven by IGF1R and BCL2 3＇-untranslated regions in SGC7901/DDP cells suggested that IGF1R and BCL2 were both direct target genes of miR-503.Enforced miR-503 expression in SGC7901/DDP cells reduced expression of the target proteins,inhibited proliferation,and sensitized the cells to DDP-induced apoptosis.Conclusion Our findings suggest that hsa-miR-503 modulates cisplatin resistance of human gastric cancer cells at least in part by targeting IGF1R and BCL2.展开更多
目的:探讨黄芪-莪术联合顺铂(DDP)抗肝癌的作用机制。方法:构建人肝癌裸鼠原位移植瘤模型。成瘤后,将其随机分为模型组、顺铂组(DDP,2 mg·kg-1,ip),黄芪-莪术高、中、低剂量(H,M,L,12,6,3 g·kg-1·d-1,ig)组,黄芪-莪术高...目的:探讨黄芪-莪术联合顺铂(DDP)抗肝癌的作用机制。方法:构建人肝癌裸鼠原位移植瘤模型。成瘤后,将其随机分为模型组、顺铂组(DDP,2 mg·kg-1,ip),黄芪-莪术高、中、低剂量(H,M,L,12,6,3 g·kg-1·d-1,ig)组,黄芪-莪术高剂量+顺铂组(H+DDP),黄芪-莪术中剂量+顺铂组(M+DDP),黄芪-莪术低剂量+顺铂组(L+DDP),每组8只。采用Td Tmediated d UTP nick end labeling(TUNEL)法观察黄芪-莪术联合顺铂对人肝癌细胞Hep G2的原位诱导凋亡作用,采用酶联免疫吸附法(ELISA)检测其对凋亡相关蛋白B淋巴细胞瘤-2(Bcl-2)的影响,采用实时荧光定量聚合酶链式反应(Real-time PCR)观察人肝癌裸鼠肿瘤组织中microRNA(miR)-122a,miR-221,miR-151的表达。结果:H,H+DDP,M+DDP,L+DDP组均有肿瘤细胞凋亡,镜下观察肿瘤细胞核内呈棕黄色,核高度凝聚,部分细胞脱落,与模型组比较有明显的凋亡现象发生(P<0.05,P<0.01),以H+DDP组诱导凋亡作用最为显著。与模型组比较,H,M,H+DDP,M+DDP,L+DDP组血清中Bcl-2含量均显著降低(P<0.01),以H+DDP组降低最为显著。与DDP组比较,H,M,L,H+DDP,M+DDP,L+DDP均能显著上调miR-122a的表达(P<0.01),H+DDP对miR-221,miR-151的表达有显著抑制作用(P<0.01)。结论:黄芪-莪术能显著诱导人肝癌细胞Hep G2凋亡,且诱导凋亡作用与剂量有一定的正相关性,其机制可能与显著下调Bcl-2表达,上调miR-122a,下调miR-221,miR-151的表达有关,与DDP合用表现为协同增效作用。展开更多
目的探讨清心开窍方中皂苷、挥发油及多糖有效成分对淀粉样蛋白(Aβ)1-40海马注射诱导痴呆(Alzheimer's disease,AD)大鼠海马区Bax、Bcl-2、Caspase-3及βAPP表达的影响。方法选取112只雄性SD大鼠,随机分为7组,每组16只,分别为正常...目的探讨清心开窍方中皂苷、挥发油及多糖有效成分对淀粉样蛋白(Aβ)1-40海马注射诱导痴呆(Alzheimer's disease,AD)大鼠海马区Bax、Bcl-2、Caspase-3及βAPP表达的影响。方法选取112只雄性SD大鼠,随机分为7组,每组16只,分别为正常组、假手术组、模型组、安理申组、皂苷组、挥发油组、多糖组。采用海马注射Aβ_(1-40)诱导AD大鼠模型。造模后第2天开始灌胃,正常组、假手术组、模型组给予等量双蒸水灌胃,安理申组[盐酸多奈哌齐片,1.67 mg/(kg·d)]、皂苷组[9 m L/(kg·d)]、挥发油组[3.33 m L/(kg·d)]、多糖组[8.33 m L/(kg·d)]灌胃,每天1次,连续2周(上午10:00)。灌胃结束后,采用Morris水迷宫测试大鼠的空间学习记忆能力;采用TUNEL染色检测海马CA1区细胞凋亡;采用免疫组化、实时定量荧光PCR及WB法检测AD大鼠海马区Bax、Bcl-2、Caspase-3及βAPP表达。结果造模前各组大鼠同一时间点的逃避潜伏期、穿台次数比较,差异均无统计学意义(P>0.05),且逃避潜伏期随时间推移逐渐缩短。造模后,与模型组比较,除挥发油组、多糖组外,安理申组、皂苷组逃避潜伏期均缩短,穿台次数显著增多(P<0.05,P<0.01);与模型组比较,皂苷组、挥发油组、多糖组大鼠海马CA1区凋亡细胞数量明显减少(P<0.05,P<0.01);Bcl-2表达上调,Bax、Caspase-3、βAPP表达下调,Bcl-2/Bax比值明显提高(P<0.05,P<0.01)。结论清心开窍方3种有效成分能不同程度地改善AD大鼠的学习记忆能力,其机制可能与降低海马区Bax、Caspase-3及βAPP表达,提高Bcl-2表达,抑制AD大鼠海马区内细胞凋亡有关。展开更多
基金This research was supported by grants from the National Natural Science Foundation of China （No.81201705 and No.81201796） and the Natural Science Foundation of Jiangsu Province （No.BK2012442）.
文摘Background Studies have shown that the drug resistance of gastric cancer cells can be modulated by abnormal expression of microRNAs （miRNAs）.We investigated the role of miR-503 in the development of cisplatin resistance in human gastric cancer cell lines.Methods MiR-503 expression was measured by quantitative real-time PCR.MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide） and clonogenic assays were used to examine changes in cell viability and the drug resistance phenotype of cancer cells associated with upregulation or downregulation of the miRNA.A dual-luciferase activity assay was used to verify target genes of miR-503.Immunohistochemistry,Western blotting analysis,and a flow cytometric apoptosis assay were used to elucidate the mechanism by which miR-503 modulates drug resistance in cancer cells.Results MiR-503 was significantly downregulated in gastric cancer tissues and several gastric cancer cell lines.Additionally,downregulation of miR-503 in the cisplatin （DDP）-resistant gastric cancer cell line SGC7901/DDP was concurrent with the upregulation of insulin-like growth factor-1 receptor （IGF1R） and B-cell lymphoma 2 （BCL2） expression compared with the parental SGC7901 cell line.An in vitro drug sensitivity assay showed that overexpression of miR-503 sensitized SGC7901/DDP cells to cisplatin.The luciferase activity of reporters driven by IGF1R and BCL2 3＇-untranslated regions in SGC7901/DDP cells suggested that IGF1R and BCL2 were both direct target genes of miR-503.Enforced miR-503 expression in SGC7901/DDP cells reduced expression of the target proteins,inhibited proliferation,and sensitized the cells to DDP-induced apoptosis.Conclusion Our findings suggest that hsa-miR-503 modulates cisplatin resistance of human gastric cancer cells at least in part by targeting IGF1R and BCL2.
文摘目的:探讨黄芪-莪术联合顺铂(DDP)抗肝癌的作用机制。方法:构建人肝癌裸鼠原位移植瘤模型。成瘤后,将其随机分为模型组、顺铂组(DDP,2 mg·kg-1,ip),黄芪-莪术高、中、低剂量(H,M,L,12,6,3 g·kg-1·d-1,ig)组,黄芪-莪术高剂量+顺铂组(H+DDP),黄芪-莪术中剂量+顺铂组(M+DDP),黄芪-莪术低剂量+顺铂组(L+DDP),每组8只。采用Td Tmediated d UTP nick end labeling(TUNEL)法观察黄芪-莪术联合顺铂对人肝癌细胞Hep G2的原位诱导凋亡作用,采用酶联免疫吸附法(ELISA)检测其对凋亡相关蛋白B淋巴细胞瘤-2(Bcl-2)的影响,采用实时荧光定量聚合酶链式反应(Real-time PCR)观察人肝癌裸鼠肿瘤组织中microRNA(miR)-122a,miR-221,miR-151的表达。结果:H,H+DDP,M+DDP,L+DDP组均有肿瘤细胞凋亡,镜下观察肿瘤细胞核内呈棕黄色,核高度凝聚,部分细胞脱落,与模型组比较有明显的凋亡现象发生(P<0.05,P<0.01),以H+DDP组诱导凋亡作用最为显著。与模型组比较,H,M,H+DDP,M+DDP,L+DDP组血清中Bcl-2含量均显著降低(P<0.01),以H+DDP组降低最为显著。与DDP组比较,H,M,L,H+DDP,M+DDP,L+DDP均能显著上调miR-122a的表达(P<0.01),H+DDP对miR-221,miR-151的表达有显著抑制作用(P<0.01)。结论:黄芪-莪术能显著诱导人肝癌细胞Hep G2凋亡,且诱导凋亡作用与剂量有一定的正相关性,其机制可能与显著下调Bcl-2表达,上调miR-122a,下调miR-221,miR-151的表达有关,与DDP合用表现为协同增效作用。
文摘目的探讨清心开窍方中皂苷、挥发油及多糖有效成分对淀粉样蛋白(Aβ)1-40海马注射诱导痴呆(Alzheimer's disease,AD)大鼠海马区Bax、Bcl-2、Caspase-3及βAPP表达的影响。方法选取112只雄性SD大鼠,随机分为7组,每组16只,分别为正常组、假手术组、模型组、安理申组、皂苷组、挥发油组、多糖组。采用海马注射Aβ_(1-40)诱导AD大鼠模型。造模后第2天开始灌胃,正常组、假手术组、模型组给予等量双蒸水灌胃,安理申组[盐酸多奈哌齐片,1.67 mg/(kg·d)]、皂苷组[9 m L/(kg·d)]、挥发油组[3.33 m L/(kg·d)]、多糖组[8.33 m L/(kg·d)]灌胃,每天1次,连续2周(上午10:00)。灌胃结束后,采用Morris水迷宫测试大鼠的空间学习记忆能力;采用TUNEL染色检测海马CA1区细胞凋亡;采用免疫组化、实时定量荧光PCR及WB法检测AD大鼠海马区Bax、Bcl-2、Caspase-3及βAPP表达。结果造模前各组大鼠同一时间点的逃避潜伏期、穿台次数比较,差异均无统计学意义(P>0.05),且逃避潜伏期随时间推移逐渐缩短。造模后,与模型组比较,除挥发油组、多糖组外,安理申组、皂苷组逃避潜伏期均缩短,穿台次数显著增多(P<0.05,P<0.01);与模型组比较,皂苷组、挥发油组、多糖组大鼠海马CA1区凋亡细胞数量明显减少(P<0.05,P<0.01);Bcl-2表达上调,Bax、Caspase-3、βAPP表达下调,Bcl-2/Bax比值明显提高(P<0.05,P<0.01)。结论清心开窍方3种有效成分能不同程度地改善AD大鼠的学习记忆能力,其机制可能与降低海马区Bax、Caspase-3及βAPP表达,提高Bcl-2表达,抑制AD大鼠海马区内细胞凋亡有关。
