冷休克对PG、HeLa细胞周期调控及p21WAF1/cip1蛋白表达的影响

目的 研究冷休克对p5 3基因突变的PG细胞、p5 3野生型的HeLa细胞的周期调控及 p2 1WAF1/cip1蛋白表达的影响。方法 将PG、HeLa细胞置 4℃冷冻 4h ,使细胞发生冷休克 ,用流式细胞仪分析细胞DNA含量及凋亡细胞百分率 ,Westernblot检测 p2 1WAF/cip1蛋白的表达。 结果 冷休克诱导PG、HeLa细胞发生G2 /M期周期阻滞及凋亡 ,p2 1WAF/cip1蛋白表达增高 (PG以 12h、HeLa以 18h最为显著 )。冷休克诱导PG、HeLa细胞发生G2 /M期周期阻滞及凋亡与 p2 1WAF/cip1蛋白表达增高同步。结论 冷休克诱导PG、HeLa细胞发生G2 /M期阻滞及凋亡、p2 1WAF/cip1表达的增高与细胞的 p5 3状态无关。

二烯丙基二硫对人白血病细胞HL-60增殖、细胞周期及p21表达的影响

目的观察二烯丙基二硫(DADS)作用于人白血病细胞系HL-60后,细胞增殖、细胞周期及细胞周期素依赖性激酶抑制蛋白p21表达的变化,探讨DADS抑制HL-60增殖、诱导G2/M阻滞的作用机制。方法不同浓度DADS作用HL-60后,MTT法检测细胞增殖情况,流式细胞仪检测细胞周期,Westernblot检测p21蛋白水平。结果在一定浓度范围之内,DADS能抑制HL-60细胞增殖,细胞周期发生G2/M期阻滞,并上调p21蛋白水平。结论DADS能通过上调p21的表达而抑制HL-60增殖,诱导其G2/M期阻滞。

CalothrixinB衍生物对白血病K562细胞的抑制作用及机制

目的:研究CalothrixinB衍生物L20对白血病K562细胞的抑制作用及其机制。方法:采用四唑盐(MTT)法检测化合物L20对K562细胞的抑制作用,使用流式细胞分析仪检测化合物L20对K562细胞凋亡及周期的影响,用DCFH-DA标记的荧光探针通过荧光显微镜观察活性氧(ROS)的改变,Western蛋白印迹检测相关蛋白的表达。结果:L20处理后的K562细胞增殖受到明显抑制,L20能够诱导K562细胞凋亡,并使其细胞周期阻滞在G 2/M期,L20还可以使ROS在K562细胞中堆积;在蛋白水平上L20能够下调p-ERK、BCL-2和p-CDC25C,上调BAX、p-CDK1及CDC25C,并激活Caspase家族。结论:L20具有通过MAPK通路诱导K562细胞凋亡及将细胞周期阻滞在G 2/M期的活性。

Influence on radiosensitivity of lung glandular cancer cells when ERCC1 gene silenced by targeted siRNA

Objective:To identify the influence on radiosensitivity of lung glandular cancer cells when excisions repair cross-complementing group1(ERCC1) gene was silenced by targeted siR NA.Methods:siR NA which targeting to ERCC1 and control siR NA was designed and synthesized.The human lung glandular cancer SPC-A-1 cells was transfected.A total of 56 nude mice were divided into two groups,and two kinds of SPC-A-1 cells were transplanted to armpit of right forelimb,to establish the nude mice subcutaneous xenotransplanted tumor model of human lung glandular cancer cells.After the tumor was developed,the nude mice were randomly divided into four groups and accepted different doses of X-Ray radiation,then the change of tumor volume,survival time of mice in every group were recorded and the average lifetime was calculated.Twenty-one days later of X-ray experiment,two mice were taken and sacrificed in each group and the tumors organizations were stripped.The cell apoptosis rate and cell cycle distributions were obtained by FCM(flow cytometry).Results:The volume of tumor which ERCC1 gene was silenced was less than single irradiation group after X-ray irradiation,and the growth speed was slower and the lifetime of mice was lengthened as well(P<0.05).The cells apoptosis rate and the rate of G2/M cells which ERCC1 gene was silenced were higher than the same dose control group and the rate of G_1 cells were lower,which indicated that the cells could be stopped at G_2/M point,the cell proliferation was inhibited,the cell apoptosis was promoted and the radiation sensitivity was improved after the ERCC1 was silenced.Conclusions:The radiation sensitivity of lung glandular tumor could be improved after the ERCC1 gene was silenced by siR NA.

Anti-proliferative and apoptotic effects of S1,a tetrandrine derivative,in human gastric cancer BGC-823 cells

The aim of the study was to investigate the anti-proliferation and apoptosis-inducing effects of S1, a novel tetrandrine derivative, in human gastric cancer BGC-823 cells and explore the possible mechanism of action. The anti-proliferative activity was determined by MTT assay; the induction of cell cycle arrest and apoptosis were detected by flow cytometry. Quantitative real time RT-PCR and Western blotting were used to evaluate the m RNA and protein expression levels in mitochondrial pathway. S1 significantly reduced cell viability and induced a G2/M phase arrest and apoptosis in dose- and time-dependent manner. Further studies showed that S1 increased m RNA and protein expression of Bax and the Bax/Bcl-2 ratio. Moreover, S1 decreased the protein expression of procaspase-9 and procaspase-3, suggesting that the induction of apoptosis may be related to the alteration of the ratio of Bax/Bcl-2 and the activation of caspases. These findings suggested that S1 merits further investigation as a novel therapeutic agent for the treatment of human gastric cancer.

Sinomenine ester derivative inhibits glioblastoma by inducing mitochondria-dependent apoptosis and autophagy by PI3K/AKT/mTOR and AMPK/mTOR pathway

Glioblastoma multiforme(GBM)in the central nervous system is the most lethal advanced glioma and currently there is no effective treatment for it.Studies of sinomenine,an alkaloid from the Chinese medicinal plant,Sinomenium acutum,showed that it had inhibitory effects on several kinds of cancer.Here,we synthesized a sinomenine derivative,sino-wcj-33(SW33),tested it for antitumor activity on GBM and explored the underlying mechanism.SW33 significantly inhibited proliferation and colony formation of GBM and reduced migration and invasion of U87 and U251 cells.It also arrested the cell cycle at G2/M phase and induced mitochondria-dependent apoptosis.Differential gene enrichment analysis and pathway validation showed that SW33 exerted anti-GBM effects by regulating PI3 K/AKT and AMPK signaling pathways and significantly suppressed tumorigenicity with no obvious adverse effects on the body.SW33 also induced autophagy through the PI3 K/AKT/mTOR and AMPK/mTOR pathways.Thus,SW33 appears to be a promising drug for treating GBM effectively and safely.

阻断TRPC6通道对人子宫内膜癌细胞和裸鼠移植瘤放射敏感性的影响

目的:探讨阻断瞬时受体电位阳离子通道6(TRPC6)对子宫内膜癌细胞和裸鼠移植瘤放射敏感性的影响。方法:选用高表达TRPC6的子宫内膜癌细胞株HEC-1A,用阻断剂SKF96365阻断子宫内膜癌细胞中TRPC6表达,流式细胞仪检测细胞周期。将HEC-1A细胞分为4组:对照组、单纯SKF96365组、单纯照射组和SKF96365+照射组(10μmol/L SKF96365+放射),计算细胞克隆数,判断细胞的增殖能力和放射增敏率。将32只雌性裸鼠随机分为4组,每组8只,分别为单纯SKF96365组、单纯照射组、SKF96365+照射组和对照组,右腹皮下注射5×10~6个细胞,每周测量裸鼠皮下肿瘤体积,接种12周后处死小鼠,测肿瘤的重量和体积,计算肿瘤生长延迟时间(TGD)和放射增敏因子。结果:SKF96365处理后,子宫内膜癌HEC-1A细胞中G_2/M期细胞百分比明显增加,G_0/G_1期百分比减少。SKF96365+照射组的细胞克隆数最低。裸鼠的实验结果与细胞实验结果相似,SKF96365+照射组裸鼠的皮下移植瘤体积和重量最小。结论:阻断TRPC6通道对子宫内膜癌HEC-1A细胞和裸鼠的肿瘤均有明显的放射增敏作用。TRPC6通道可作为子宫内膜癌放射增敏的调控点,可能成为子宫内膜癌治疗的新靶点。