Effect of Gambogic acid on the regulation of hERG channel in K562 cells <Emphasis Type="Italic">in vitro</Emphasis>

Overexpression of human ether-h-go-go （eag） related gene （bERG） has been found in a broad range of human leukemia cell lines and primary human leukemia. The block of hERG protein might be a potential therapeutic strategy for leukemia. Gambogic acid （GA） has recently exhibited marked anti-tumor potency on solid tumors of various derivations. Here, we investigated the anti-leukemia effects of GA and its relation to the regulation of hERG in K562 leukemia cells in vitro. K562 cells were treated with various concentrations of GA （0.125-8.0 μmol/L） for 0-72 h. MTT assay was used to evaluate the inhibition effect of GA on the growth of K562 cells. Cell apoptosis was measured through both Annexin-V FITC/PI double-labeled cytometry and transmission electron microscopy. Cell cycle regulation was studied by a propidium iodide method. RT-PCR and Western blot were applied to detect the expression level of hERG in K562 cells. GA presented striking growth inhibition and apoptosis induction potency on K562 ceils in vitro in a time- and dose-dependent manner. The IC50 value of GA for 24 h was 2.637±0.208 μmol/L. Moreover, GA induced K562 cells arrested in G0/G1 phase, accordingly, cells in S phase decreased gradually, and no obvious changes were found in G2/M phase cells. Under the transmission electron microscopy, apoptotic bodies containing nuclear fragments were found in GA-treated K562 cells. After treatment with GA of 2.0 μmol/L for 24 h, the percentage of apoptotic cells was increased from 4.09% to 18.47% （P〈0.01）. Overexpression of hERG channel was found in K562 cells, while GA could down-regulate it at both protein and mRNA levels （P〈0.01）. It was concluded that GA exhibited its anti-leukemia effects partially through down-regulating the expression level of hERG channel in K562 cells, suggesting that GA may be a potential agent against leukemia with a mechanism of blocking hERG channel.     

Anti-cancer Effects of Deguelin on Human Leukemia K562 and K562/ADM Cells In Vitro

In order to investigate the anti-cancer effects of deguelin and on K562 and K562/ADM cells in vitro and the underlying molecular mechanism and compare the cytotoxicity of deguelin on K562, K562/ADM cells and human peripheral blood mononuclear cells (PBMCs). The effects of de- guelin on cell proliferation were assessed by MTT assay. Apoptosis were detected by AnnexinⅤ/PI double-labeled cytometry. The effects of deguelin on the cell cycle were studied by a propidium io- dide method. Our study showed that deguelin inhibited the proliferation of K562 cell and K562/ADM cell in a time- and dose-dependent manner and had minimal effects on normal human peripheral blood mononuclear cells. The ratio of IC50 value of deguelin of 24 h on K562/ADM cells to K562 cells was only 1.27, which was significantly lower than the ratio of IC50 value of ADM (higher than 20). Deguelin could induce apoptosis of K562 cells and K562/ADM cells. K562 cells were arrested at G2/M phase while K562/ADM cells were arrested at G0/G1 phase. Our results suggested that deguelin was a novel anti-leukemia agents with high efficacy and low toxicity and it is also a promising agent for reversing drug resistance.     

苦参碱联合LY294002对人髓系白血病K562细胞增殖、凋亡和细胞周期的影响

目的 探究苦参碱（Mat）联合LY294002对人髓系白血病K562细胞增殖、凋亡和细胞周期的影响及可能机制。方法 采用CCK-8法检测不同浓度Mat单药和联合LY294002对K562细胞增殖的影响;将K562细胞分为对照组、Mat组、LY294002组和Mat+LY294002组,分别采用0.4 g/L Mat及10μmol/L LY294002单独或联合干预48 h后,应用光学显微镜观察细胞形态变化,流式细胞术annexinⅤ-FITC/PI双标记检测细胞凋亡,PI单标记检测细胞周期变化,Western blot法检测Mat联合LY294002对K562细胞p-mTOR、p-PI3K、Akt、p-Akt、CyclinD1、Bcl-2、Caspase-9蛋白表达的影响。结果 CCK-8结果显示,不同浓度Mat单药和联合LY294002均可抑制K562细胞的增殖,具有时间和浓度依赖性,且联合组增殖抑制率比单药组明显升高（P<0.01）。形态学检查显示,联合用药组比单药组凋亡表现更明显。流式细胞结果显示,与对照组及单药组相比,联合组显著促进细胞凋亡[（42.50±2.63）%,P...     

一种天然植物抗菌液PAMs对人白血病K562细胞的促凋亡作用

初步研究一种天然植物抗菌液(PAMs)对白血病K562细胞的杀伤作用及抗肿瘤分子作用机制。MTT法确定PAMs对K562细胞的增殖抑制作用和具有的浓度和时间依赖性;AO-EB双染、Annexin-FITC/PI流式细胞仪染色观察显示PAMs对K562细胞的杀伤作用与细胞凋亡相关,这也被进一步的分子水平与酶活力检测所证实。FQ-PCR基因表达检测发现,PAMs处理后,K562细胞株中caspase-3、caspase-9、bax等促凋亡相关基因有所上升,而抑制凋亡基因bcl-2表达下降,Western blot法检测到PAMs上调caspase-3的表达量,同时下调抑制凋亡蛋白survivin的表达。这也与caspase酶活性测定结果相一致,PAMs处理后的K562,其caspase-3、-9活性均有所上升。所有这些结果一方面揭示PAMs对白血病K562细胞株具有强的杀伤作用,同时在形态和分子水平揭示其抗肿瘤抑制作用途径与诱导细胞凋亡的密切相关性,为PAMs作为抗白血病抗肿瘤中药的研发提供参考。     

虫草素对人骨肉瘤MG-63细胞凋亡的影响及其机制研究

目的 研究虫草素对人骨肉瘤MG-63细胞凋亡的影响及其机制。方法 采用CCK-8实验检测不同浓度虫草素作用于MG-63骨肉瘤细胞24h和48h后对癌细胞增殖的抑制作用;采用流式细胞术分析虫草素对MG-63细胞周期分布及凋亡的影响;采用Western blot法检测虫草素对MG-63细胞凋亡相关蛋白Bax、Bcl-2、cleaved caspase-9、cleaved caspase-3及NICD1、Hes1蛋白表达的影响。结果 虫草素对人骨肉瘤MG-63细胞有明显的增殖抑制作用,导致MG-63细胞周期阻滞于G₀/G₁期并诱导细胞凋亡;虫草素可上调Bax、cleaved caspase-9和cleaved caspase-3蛋白的表达并下调Bcl-2,NICD1和Hes1蛋白的表达。结论 虫草素通过抑制骨肉瘤细胞增殖,诱导细胞周期阻滞于G₀/G₁期并通过线粒体凋亡途径诱导MG-63细胞凋亡从而发挥抗骨肉瘤作用,可能骨肉瘤细胞中Notch信号通路活性下调有关。     

Reversal effect of bufalin on multidrug resistance in K562/VCR vincristine-resistant leukemia cell line

ObjectiveTo probe insights into the reversal effect of bufalin on vincristine-acquired multidrug resistance (MDR) in human leukemia cell line K562/VCR.MethodsProliferative inhibition rate and the reversal index (RI) of bufalin were determined by Methyl thiazolyl tetrazolium assay. The uptake of Adriamycin (ADM) in K562/VCR cells, cell cycle and apoptosis rate were determined by flow cytometry (FCM). Cell morphologic changes were observed with Wright-Giemsa staining. The expression of P-glycoprotein (P-gp), multidrug-associated protein-1 (MRP1), Bcl-xL and Bax protein were measured by immunocytochemistry.ResultsThe human leukemia multidrug resistant K562/VCR cells showed no cross-resistance to bufalin. The RIs of bufalin at concentrations of 0.0002, 0.001 and 0.005 μmol/L were 4.85, 6.94 and 14.77, respectively. Preincubation of 0.001 μmol/L bufalin for 2 h could increase intracellular ADM fluorescence intensity to 28.07% (P<0.05) and down-regulate MRP1 expression simultaneously, but no remarkable effect was found on P-gp protein. Cell cycle analysis indicated increased apoptosis rate and apparent decreased G2/M phase proportion after treatment with bufalin. When exposed to 0.01 μmol/L bufalin, typical morphological changes of apoptosis could be observed. Down-regulation of Bcl-xL and up-regulation of Bax expression in K562/VCR cells could be detected by immunocytochemistry.ConclusionBufalin could partly reverse the MDR of K562/VCR cells, with a possible mechanism of down-regulating MRP1 expression and activating apoptosis pathway by altering Bcl-xL/Bax ratio.     

Paris saponin I induces G<Subscript>2</Subscript>/M cell cycle arrest and apoptosis in human gastric carcinoma SGC7901 cells

The aim of this study was to investigate the effect of Paris saponinⅠ(PSⅠ)on human gas-tric carcinoma cell growth and apoptosis and to explore the potential mechanisms.The proliferation of SGC7901 cells was monitored by the MTT cell viability assay,while the nuclear morphology of apoptotic cells was assessed by Hoechst 33258 staining.Flow cytometry was performed to analyze the cell cycle progression of propidium iodide(PI)-stained SGC7901 cells and the apoptotic rate of annex-inⅤ/PI-stained cells.Western blotting was used to examine the expression of several cell cycle proteins,including cyclin B1 and Cdk1,and the apoptosis-regulated proteins Bcl-2,Bax,cytochrome c,procas-pase-9,and procaspase-3.The MTT assay demonstrated that PSⅠ could induce significant dose-and time-dependent inhibition of SGC7901 cell proliferation.Marked morphological changes,including condensation of chromatin,nuclear fragmentation and apoptotic bodies were clearly shown on Hoechst 33258 staining.PSⅠ treatment also resulted in the disruption of the cell cycle at G2/M and the induction of apoptosis.Following PSⅠ treatment,the cell cycle-related proteins cyclin B1 and Cdk1 were down-regulated.Expression of the pro-apoptotic protein Bax was increased,while anti-apoptotic protein Bcl-2 decreased.PSⅠ treatment resulted in elevated cytoplasmic cytochrome c and activation of the apoptotic proteases caspase-9 and caspase-3.These data indicate that PSⅠ acts as an inhibitor of proliferation in SGC7901 cells by inducing cell cycle arrest and mitochondria-dependent apoptosis.PSⅠ is a potential therapeutic agent against human gastric carcinoma.     

胃祺饮乙醇提取物可诱导AGS细胞G2/M 期阻滞及凋亡

Objective:To evaluate the effects of the ethanol extract isolated from Weiqi Decoction(胃祺饮,WQD-EE)on AGS cell proliferation and apoptosis.Methods:By using high-performance liquid chromatography with ultraviolet detectors(HPLC-UV)assay and MTT method,the main compounds in WQD-EE and cell viability were detected.And cell cycle distributions were determined by flow cytometry with propidium iodine(PI)staining while apoptosis was detected by flow cytometry with annexin V/Pl double staining.Finally,caspase-3 activities were measured by calorimetric method and protein expression was determined by Western blotting.Results:HPLC analysis showed that naringin(35.92μg/mg),nobiletin(21.98μg/mg),neohesperidin(17.98μg/mg)and tangeretin(0.756μg/mg)may be the main compounds in WQD-EE.WQD-EE not only inhibited AGS and MCF7 cell proliferation in a dose-dependent manner,but also blocked cell cycle progression at G_2/M stage as well as inducing cell apoptosis at concentrations triggering significant inhibition of proliferation and cell cycle arrest in AGS cells.While at 0.5 mg/mL,WQD-EE significantly increased caspase-3 activity by 2.75 and 7.47 times at 24 h and 48 h,respectively.Moreover,WQD-EE in one hand reduced protein expressions of p53 and cyclin B1,and in other hand enhanced protein expressions of cytochrome c and Bax.Protein levels of Bcl-2,Fas L and Fas were not significantly affected by WQD-EE.Conclusions:WQD-EE inhibits AGS cell proliferation through G_2/M arrest due to down-regulation of cyclin Bi protein expression,and promotes apoptosis by caspase-3 and mitochondria-dependent pathways,but not by p53-dependent pathway.     

痰热清注射液抑制白血病细胞体外增殖及其作用机制（英文）

目的：探讨痰热清注射液对人白血病细胞体外增殖的影响及其作用机制。方法：将痰热清注射液以体积比稀释成1：2、1：4、1：8、1：16、1：32、1：64、1：128、1：256和1？512,共9个浓度组,分别处理增殖期慢性髓系白血病K562细胞和急性T淋巴细胞白血病Molt4细胞,镜下观察不同时间点各浓度组细胞生长情况,应用活细胞计数试剂盒检测细胞增殖能力,绘制生长曲线,计算抑制率和半数抑制浓度（half inhibitory concentration,IC50）;分别采用碘化丙啶染色法和碘化丙啶/膜联蛋白V双染法,通过流式细胞术检测Molt4细胞周期及凋亡的变化;采用实时定量聚合酶链反应方法分析痰热清注射液处理Molt4细胞后凋亡相关基因caspase-3和bcl-2的表达量变化。结果：痰热清注射液对K562和Molt4细胞增殖具有抑制作用,1？2至1？16稀释浓度组的细胞毒性大,细胞基本死亡;抑制作用呈剂量和时间依赖性,IC50分别为1？333和1？142稀释浓度。痰热清注射液1？32浓度组处理72h后,Molt4细胞处于S期的数量明显减少（P〈0.05）,凋亡细胞比例明显增加（P〈0.05）;同时,caspase-3表达增加,bcl-2表达明显减少（P〈0.05）。结论：痰热清注射液可抑制白血病细胞体外增殖并促进其凋亡,该作用可能是通过减少S期细胞数量,下调bcl-2基因表达和上调caspase-3基因表达而实现的。     

大麻受体激动剂WIN对白血病K562细胞增殖和诱导凋亡作用的研究

目的探讨大麻受体激动剂W／N-55,212-2（WIN）对白血病K562细胞增殖和凋亡的作用及机制。方法将细胞分成对照组和不同剂量大麻受体激动剂wIN用药组。CCK-8测定WIN对K562细胞增殖的影响;DAPI染色观察细胞核形态变化;JC-1分析线粒体膜电位变化;分光光度法检测Caspase-3、Caspase-8、Caspase-9的活性;流式细胞仪分析细胞凋亡率变化;Western印迹法分析Bax、Bcl-2及C-myc蛋白的表达。结果与对照组相比较,5、10、20μmol／L的WIN处理K562细胞24、48h后,增殖抑制作用明显且具有剂量依赖性,差异有统计学意义（P〈0．05）。DAPI染色和线粒体膜电位检测结果显示,K562细胞发生凋亡。流式细胞仪检测结果显示,细胞凋亡率升高。WIN处理24h后,Caspase-3、Caspase-8、Caspase-9活性均增加（P〈0．05）。Western印迹法显示,Bax蛋白表达增加,C-myc、Bcl-2蛋白表达下降。结论大麻受体激动剂WIN能抑制白血病K562细胞增殖,并诱导凋亡,其机制可能通过上调Bax蛋白表达,下调C-myc、Bcl-2蛋白表达,以及促使线粒体跨膜电位下降。激活Caspase．3、Caspase-8、Caspase-9蛋白而实现。     

Arsenic Trioxide Inhibits Proliferation in K562 Cells by Changing Cell Cycle and Survivin Expression

To study the mechanisms involved in the inhibition of chronic myeloid leukemic cells (K562) proliferation induced by arsenic trioxide (As2O3) and to explore the potential role of Survivin, an inhibitor of apoptosis protein, in the regulation of As203 induced cell apoptosis, K562 cells were cultured with As203 of different concentrations. Cells were collected for proliferation analysis by MTT assay. Cell cycle distribution and cell apoptosis were analyzed by flow cytometry. Expression of Survivin protein and mRNA were detected by flow cytometry and RT-PCR, respectively. Our results showed that As2O3 (2-10/μmol/L) inhibited K562 cells growth effectively, but it did not induce cells apoptosis significantly. The percentage of K562 cells at G2/M phase increased in proportion to As2O3 concentrations, and the expression of Survivin mRNA and content of Survivin protein was up-regulated accordingly. It is concluded that As2O3 inhibited K562 cells growth by inducing cell cycle arrest mainly at G2/M phase. Over-expression of Survivin gene and protein might be one of the possible mechanisms contributing to K562 cells‘ resistance to As2O3-induced apoptosis.     

DAPK过表达对HL-60 细胞生物学功能及caspase-3 表达的影响

目的探讨死亡相关蛋白激酶（DAPK）过表达对HL-60细胞生物学功能及对caspase-3表达的影响。方法采用RT-PCR技 术检测白血病细胞株DAPK基因mRNA的表达。运用真核表达载体pReceiver-M29-DAPK,用脂质体LipofectamineTM 2000介 导转染HL-60细胞,研究其过表达对白血病细胞凋亡、细胞周期及分化的影响,并对caspase-3表达的影响。结果DAPK基因在 K562、Molt4、U937细胞表达阳性,而HL-60细胞则表达阴性。转染pReceiver-M29-DAPK后,应用流式细胞术和Hoechst33342 染色可观察到转染后HL-60细胞出现凋亡,凋亡细胞百分率显著增高。PI单染和瑞氏染色法分析观察转染前后的HL-60细胞, 各细胞周期及形态均无改变。转染后caspase-3的表达水平显著增高。结论DAPK基因过表达的HL-60细胞凋亡增强,但对 HL-60细胞周期和细胞分化无影响。Caspase-3可能参与了凋亡调控。     

Bcr/abl融合基因的小干扰RNA对K562细胞增殖和凋亡的影响

目的 观察特异性bcr/abl融合基因的siRNA对慢性粒细胞白血病K562细胞增殖和凋亡的影响。方法　设计并化学合成bcr/abl融合基因融合位点b3:a2 21个核苷酸 siRNA作用于K562细胞,用WST-8法检测细胞增殖抑制率;RT-PCR 检测 bcr/abl mRNA表达水平;PI单染流式细胞仪检测细胞周期;Annexin V-PI双染测定细胞凋亡比例;Hochest33258 染色荧光显微镜观察细胞凋亡的形态学变化。结果 ①Bcr/abl siRNA作用K562细胞24h,48h,72h后,明显抑制K562细胞增殖,各浓度组间的增殖抑制率无明显差异(p>0.05);②Bcr/abl siRNA能显着下调bcr/abl mRNA水平,各浓度组间差异无显著性(p>0.05);③Bcr/abl siRNA作用组细胞周期阻滞于G1期;④Bcr/abl siRNA作用后细胞出现明显的早期凋亡群,各浓度组间的早期凋亡率差异无统计学意义(p>0.05),细胞出现核固缩、核边集、凋亡小体等改变。结论 　特异性bcr/abl siRNA可显着抑制K562细胞bcr/abl融合基因的表达,抑制细胞的增殖,诱导凋亡,但其作用未显示明显的剂量依赖性。     

Effects of betulinic acid on proliferation and apoptosis in Jurkat cells and its in vitro mechanism

Summary  The anti-cancer effects of betulinic acid (BA) on Jurkat cells and its in vitro mechanism were examined by using MTT assay. Apoptosis was detected by using Hoechst33258 staining and annexin-V/PI double-labeled cytometry. The effects of betulinic acid on the cell cycle of Jurkat cells were studied by propidium iodide method. RT-PCR and Western blotting were used to analyze the changes of cyclin D3, bcl-xl mRNA and protein levels in Jurkat cells after treatment with betulinic acid. Our results showed the proliferation of Jurkat cells was decreased in betulinic acid-treated group with a 24-h IC50 value being 70.00 μmol/L. Betulinic acid induced apoptosis of Jurkat cells in a time- and dose-dependent manner. The number of Jurkat cells treated with betulinic acid showed an increase in G₀/G₁ phase and decrease in S phase. After treatment with 0, 20, 60, 100 μmol/L betulinic acid for 24 h, the number of Jurkat cells was increased from (31.00±1.25)% to (58.84±0.32)% in G₀/G₁ phase, whereas it was decreased from (61.45±1.04)% to (35.82±1.95)% in S phase. PBMCs were less sensitive to the cytotoxicity of betulinic acid than Jurkat cells. The expressions of cyclin D3, bcl-xl mRNA and protein were decreased sharply in Jurkat cells treated with betulinic acid. It is concluded that betulinic acid is able to inhibit the proliferation of Jurkat cells by regulating the cell cycle, arrest cells at G₀/G₁ phase and induce the cell apoptosis. The anti-tumor effects of betulinic acid are related to the down-regulated expression of cyclin D3 and bcl-xl. Zi CHEN, Female, born in 1980, Resident This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30500686).     

Q39在缺氧条件下诱导人白血病K562细胞凋亡

目的:探索3-(4-溴苯基)-2-(乙砜基)-6-甲基喹喔啉-1,4-二氧化物(Q39)在缺氧条件下诱导人白血病K562细胞凋亡的作用机制。方法:1MTT法测定Q39对K562细胞的体外抑制作用,计算其半数抑制浓度(IC50)。24,6-Diamidino-2-Phenylindole(DAPI)荧光染料染色观察细胞的凋亡情况。3流式细胞术测定K562细胞凋亡率。4JC-1染色法观察Q39对K562细胞线粒体膜电位(△Ψm)的影响。5Western-blotting法检测低氧条件下细胞内procaspase-3、cleaved caspase-3、PARP、Bax、Bcl-2和HIF-1α蛋白表达的变化。结果:在缺氧(3%O2)条件下,Q39对K562细胞表现出较强的体外抑制增殖作用,IC50为(0.21±0.05)μmol/L。经DAPI染色证实,Q39作用6h后开始诱导K562细胞凋亡,后期细胞体积缩小,并出现凋亡小体。流式细胞术结果显示:K562细胞与Q39共孵育0、6、12和24h的凋亡率分别为2.8%、3.2%、5.9%和19.2%。JC-1染色实验结果显示:孵育0、6、12、24和48h后Q39使K562细胞的线粒体△Ψm呈明显下降趋势,并且具有时间依赖关系。Western-blotting结果显示:Q39降低K562细胞的HIF-1α、procaspase-3和Bcl-2蛋白表达,明显增加Bax和cleaved caspase-3蛋白表达,并且促使PARP裂解。结论:Q39在缺氧条件下对K562细胞有较好的抑制作用,并能通过降低HIF-1α蛋白表达和调节其他凋亡相关蛋白表达,促使K562细胞线粒体△Ψm下降,诱导细胞凋亡。Q39诱导细胞凋亡可能是通过线粒体和HIF-1α信号转导通路实现的。     

不同齿科合金对成纤维细胞增殖凋亡的影响及机制研究

目的 探讨不同齿科合金对成纤维细胞增殖凋亡的影响及机制。方法 小鼠成纤维L929细胞分为阴性对照组、金合金组、镍铬合金组和铜合金组,各组细胞培养48h后,MTT实验检测细胞增殖;流式细胞术检测细胞周期和细胞凋亡率;Western blot法检测Bcl-2、Bax、cleaved caspase-3蛋白表达。结果 金合金组和镍铬合金组细胞增殖率与阴性对照组比较,差异无统计学意义（P>0.05）,铜合金组细胞细胞增殖率显著低于阴性对照组（P<0.01）;金合金组G₁期、S期和G₂期细胞与阴性对照组差异无统计学意义（P>0.05）,镍铬合金组和铜合金组G₁期细胞显著低于阴性对照组,S期和G₂期细胞显著高于阴性对照组（P<0.05）;金合金组细胞凋亡率及Bcl-2、Bax、cleaved caspase-3蛋白表达与阴性对照组差异无统计学意义（P>0.05）,镍铬合金组和铜合金组细胞凋亡率及Bax、cleaved caspase-3蛋白表达均显著高于阴性对照组,Bcl-2蛋白表达显著低于阴性对照组（P<0.01）。结论 金合金组、镍铬合金组和铜合金组对成纤维细胞增殖凋亡均有一定的影响,金合金组的影响最小,不同齿科合金引起成纤维细胞凋亡的机制可能与调控Bcl-2、Bax、cleaved caspase-3蛋白表达有关。     

三七总皂苷对K562细胞增殖、凋亡及周期的影响及机制

目的研究三七总皂苷（PNS）对K562 细胞增殖、凋亡、周期的影响及其相关分子机制。方法采用MTT法检测PNS对
K562细胞增殖的影响;AO/EB双荧光染色法及Annexin V-FITC/PI双染色法观察细胞凋亡及死亡状况;流式细胞术检测K562
细胞的周期变化;RT-PCR检测mTOR信号通路主要分子mRNA的表达变化;Western blot 检测cleaved caspase-3 蛋白、cyclin
D1蛋白及mTOR信号通路主要蛋白及磷酸化蛋白的表达量变化。结果100~800 μg/mL的PNS 作用于K562细胞后能够抑制
细胞增殖。PNS能够上调cleaved caspase-3蛋白表达,促使K562细胞发生凋亡。并且下调cyclin D1蛋白表达,促使K562细胞
阻滞在G0/G1期。同时,PNS 能够抑制K562 细胞mTOR mRNA 表达,降低mTOR 蛋白和磷酸化蛋白p-mTOR（Ser2448）、
p-p70S6K（Thr229/389）及p-4E-BP1（Thr37/46）的表达,从而抑制mTOR信号通路活性。结论PNS 对体外培养K562细胞有抑
制增殖,促进凋亡,使其发生周期阻滞的作用。其机制可能与PNS抑制mTOR信号通路活性、上调cleaved caspase-3蛋白表达
及抑制cyclin D1蛋白表达有关。
     

Effects of POH in Combination with STI571 on the Proliferation and Apoptosis of K562 Cells

Sofar ,the 2 phenylaminopyrimidineSTI5 71isthemostsuccessfulofthemolecularlydesignedATPcompetitorsfromNovartisPharma (Basel,Switzer land) ,whichspecificallyinhibitsAbltyrosinekinaseatmicromolarconcentrations .InhibitionoftheBcr Ablkinaseactivitybythiscom…     

芒果苷减轻IL-1β诱导的软骨细胞凋亡

目的：软骨细胞凋亡是骨关节炎重要的发病机制,芒果苷具有抗炎和抗凋亡等多种药理作用,然而芒果 苷对软骨细胞凋亡的作用尚不清楚。本研究探讨芒果苷对IL-1β诱导的软骨细胞凋亡的影响。方法：将小鼠软骨细胞 ATDC5随机分为control组、IL-1β组、MFN-L组、MFN-M组、MFN-H组及MFN+LY294002组。Control组细胞不加 任何干预;IL-1β组细胞用IL-1β(10 ng/mL)处理24 h;MFN-L、MFN-M、MFN-H组细胞先分别用5、10、20 μmol/L 的芒果苷预处理 1 h,再用 IL-1β(10 ng/mL)处理 24 h;MFN+LY294002 组细胞先加入 LY294002(25 μmol/L)处理 1 h, 再加入芒果苷(20 μmol/L)处理1 h,最后再用IL-1β(10 ng/mL)处理24 h。用CCK-8检测细胞活力,流式细胞术检测细 胞凋亡,比色法检测caspase-3活性,蛋白质印迹法检测Bcl-2,Bax及磷脂酰肌醇-3-激酶/蛋白激酶B(PI3K/Akt)通路 相关蛋白质的表达。结果：与control组相比,IL-1β组细胞活力显著降低,细胞凋亡率显著上升,caspase-3活性显著 增加,Bax蛋白质表达水平显著上调,Bcl-2、p-PI3K和p-Akt蛋白质表达水平显著下调(均P<0.05)。与IL-1β组相比, MFN-L、MFN-M、MFN-H组细胞活力显著升高,细胞凋亡率显著下降,caspase-3活性显著下降,Bax蛋白质表达水 平显著下调,Bcl-2、p-PI3K和p-Akt蛋白质表达水平显著上调(均P<0.05)。与MFN-M组相比,MFN+LY294002组细 胞凋亡率显著上升,Bax蛋白质表达水平显著上调,Bcl-2蛋白质表达水平显著下调(均P<0.05)。结论：芒果苷可减 轻IL-1β诱导的软骨细胞凋亡,其保护作用是通过激活PI3K/Akt通路实现的。