山奈酚诱导人小细胞肺癌H446细胞凋亡及机制

目的探讨山奈酚对人小细胞肺癌H446细胞的抑制作用,并研究其作用机制。方法采用MTT法、DAPI染色、流式细胞术等方法检测山奈酚对H446细胞增殖及凋亡的影响;使用Western blot检测山奈酚处理后H446细胞中p53、bax和bcl-2的表达变化。结果山奈酚抑制人小细胞肺癌H446细胞增殖,促进H446细胞阻滞于S期及G2/M期,诱导该细胞株凋亡,上调p53、bax的表达水平,降低bcl-2的表达水平。结论山奈酚对H446细胞有明显的抑制作用,该抑制作用与山奈酚诱导的细胞周期阻滞和细胞凋亡有关。     

曲美他嗪对缺氧/复氧诱导人心肌细胞凋亡的影响

目的研究曲美他嗪(trimetazidine)对缺氧/复氧致人心肌细胞凋亡及其信号改变的效应。方法通过采用胶原酶/胰酶联合消化法获取人心肌细胞,采用缺氧/复氧模拟缺血/再灌注诱导细胞凋亡,选取最佳凋亡时间为缺氧24h和复氧4h,并用免疫细胞化学法检测bcl-2、bax、细胞色素C和caspase-3蛋白的变化,用原位杂交法检测bcl-2mRNA和caspase-3mRNA表达的变化,用脂肪代谢试剂曲美他嗪不同剂量干预,观察对缺氧/复氧诱导人体外培养心肌细胞凋亡及其信号bcl-2、bax、细胞色素C和caspase-3蛋白及bcl-2mRNA和caspase-3mRNA表达的影响。凋亡信号表达用平均光密度表示。用SPSS10.0进行统计分析。结果①缺氧24h/复氧4h后细胞凋亡率明显升高(18.50%±1.00%);bcl-2(0.189±0.006)下降;bax(0.240±0.002)、caspase-3(0.230±0.002)和细胞色素C(0.225±0.003)升高;bcl-2mRNA(0.300±0.003)下降;caspase-3mRNA(0.307±0.004)升高;分别与对照组比较,差异均有显著性(P<0.01)。②曲美他嗪呈剂量依赖性明显降低细胞凋亡率,降低bax、caspase-3和cytochromeC蛋白阳性率和升高bcl-2蛋白阳性率,降低caspase3mRNA表达阳性率和升高bcl-2mRNA表达阳性率(均P<0.01)。结论曲美他嗪具有抗凋亡作用,可能与升高bcl-2蛋白和bcl-2mRNA表达与降低bax、caspase-3、cytochromeC蛋白和caspase-3mRNA表达水平有关。     

山奈酚对人小细胞肺癌H446的增殖抑制和诱导凋亡作用的影响

目的 探讨山奈酚对人小细胞肺癌H446细胞生长的抑制作用和诱导凋亡作用.方法 采用MTT 法检测生长的抑制作用;流式细胞仪检测细胞凋亡;Western Blotting技术检测凋亡相关蛋白.结果 不同浓度的山奈酚能抑制人小细胞肺癌H446细胞生长,且随浓度增加抑制作用增强(P<0.01).流式结果 显示不同浓度山奈酚组...     

Emodin elicits cytotoxicity in human lung adenocarcinoma A549 cells through inducing apoptosis

This study investigated the mechanism of the cytotoxic effect of emodin, an active anthraquinone, on human lung adenocarcinoma A549 cells. In vitro growth inhibition and suppression on colony forming were used to evaluate the effects of emodin on A549 cells. Emodin’s ability in changing the expressions of apoptosis-related genes was studied by real-time RT-PCR. Emodin could significantly inhibit the growth of A549 cells with IC₅₀ = 16.85 μg/ml (~60 μM). It also concentration dependently inhibited the colony-forming ability of A549 cells with IC₅₀ = 7.60 μg/ml (~30 μM). Hallmarks of apoptosis, such as single-strand DNA breakage and DNA fragmentation, were observed in A549 cells treated with emodin. Emodin (72 h) treatment could up-regulate the gene expression of FASL (p < 0.05) and down-regulate the gene expression of C-MYC (p < 0.01), but induce no significant changes in the gene expressions of MCL1, GAPDH, BAX and CCND1. These results suggest that emodin could induce growth inhibition and apoptosis in A549 cells through modifying the extrinsic apoptotic pathways and the induction of cell cycle arrest.     

蓝萼甲素对人肺癌A549细胞的作用及其机制

<正>蓝萼甲素(glaucocalyxin A)是由唇形科香茶菜属植物香茶菜Rabdosia amethystoieds(Benth)Ham中分离提取出的二萜化合物,可抑制SiHa、Hela、HL-60等细胞株增殖[1]。本文研究了蓝萼甲素对人肺腺癌A549细胞增殖的影响,并初步探讨其机制。1材料与方法1.1材料蓝萼甲素(glaucocalyxin A),购自上海艾汇生物科技有限公司。Hoechst凋亡检测试剂盒、PARP,cleavedcaspase-3和caspase-8抗体购自上海碧云天生物公司,     

尖吻蝮蛇毒抑瘤组分I对人肺癌 A549细胞增殖抑制作用

目的：研究尖吻蝮蛇毒抑瘤组分I（ AAVC-I） 对人肺癌A549细胞增殖抑制及凋亡的作用。方法： 采用MTT法检测不同浓度的AAVC-I对A549细胞的24 h 与48 h 抑制率;应用HE染色、Hoechst33258荧光染色,从形态学观察细胞凋亡;采用免疫组化的方法,检测bax蛋白表达的变化。结果： MTT显示,AAVC-I能抑制A549细胞增殖,呈时间和剂量依赖性;AAVC-I处理24 h 后,镜下可见细胞核固缩,核深染及凋亡小体;免疫组化显示,随药物浓度增加,平均光密度值呈递增趋势,表明bax蛋白表达相应上调。结论：尖吻蝮蛇毒抑瘤组分I对人肺癌A549细胞具有抑制作用,并诱导其凋亡,可能与bax表达上调有关。     

呫吨酮并吡啶衍生物XP-16诱导人肺癌A549细胞凋亡

目的探讨呫吨酮并吡啶衍生物5,9-二(2-吡咯烷基乙酰氨基)-7H-吡啶并[4,3-c]呫吨-7-酮(XP-16)对人肺癌A549细胞的抗肿瘤作用及其可能作用机制。方法通过MTT法、细胞形态学和克隆实验观察XP-16对A549细胞增殖的影响;应用Hoechst 33258和PI双染法观察细胞凋亡;荧光分光光度计检测细胞内钙([Ca2+]i)及线粒体膜电位;qRT-PCR检测Bad和金属硫蛋白1A(metallothionein 1A,MT-1A)mRNA表达。结果 XP-16能抑制A549细胞增殖,呈剂量和时间依赖性。XP-16作用A549细胞24 h后,A549细胞出现染色质聚集、核碎裂等典型的凋亡形态学改变;随XP-16剂量的增加,A549细胞凋亡百分率逐渐增大。XP-16作用后,A549细胞的[Ca2+]i和线粒体膜电位降低、Bad和MT-1A mRNA的表达增加。结论 XP-16具有诱导A549细胞凋亡的作用,可能与其降低[Ca2+]i和线粒体膜电位有关。MT-1A表达的上调可能是[Ca2+]i降低的结果。     

辛伐他汀联合顺铂对人非小细胞肺癌A549细胞增殖的抑制作用

目的研究辛伐他汀联合顺铂对人非小细胞肺癌A549细胞的抑制作用,并探讨其作用机制。方法采用MTT法检测0.625、1.25、2.5、5、10μmol/L顺铂和3.125、6.25、12.5、25、50μmol/L辛伐他汀对A549细胞增殖抑制率的影响;考察2.5μmol/L顺铂与3.125、6.25、12.5、25、50μmol/L辛伐他汀联用对A549细胞增殖抑制作用的协同效果;Annexin V-FITC/PI双染后流式细胞术检测5μmol/L顺铂与25μmol/L辛伐他汀联合应用对对A549细胞凋亡率的影响;分光光度法检测辛伐他汀(25μmol/L)联合顺铂(2.5μmol/L)对A549细胞caspase-3活性的影响。结果辛伐他汀或顺铂对A549细胞的增殖有显著的抑制作用,随着浓度的增加、时间的延长,呈时间、剂量相关性,其抑制作用增强(P0.01)。顺铂(2.5μmol/L)与不同浓度(3.125、6.25、12.5、25、50μmol/L)辛伐他汀联用对A549细胞的增殖有抑制作用,随着时间的延长,辛伐他汀剂量的增加,两者联用抑制作用呈增强的趋势(P0.01),2.5μmol/L顺铂联用辛伐他汀25μmol/L的抑制作用具有协同效果。25μmol/L辛伐他汀和2.5μmol/L顺铂能有效地诱导A549细胞的凋亡,而且两者联合使用可以显著增加A549细胞的凋亡率。25μmol/L辛伐他汀联合2.5μmol/L顺铂应可以显著增加A549细胞的caspase-3酶活性。结论辛伐他汀能够显著增强顺铂对A549细胞增殖抑制、诱导凋亡的作用,可能通过上调caspase-3活性诱导A549细胞凋亡。     

2,3-吲哚醌对人神经母细胞瘤细胞SH-SY5Y凋亡和端粒酶表达的影响

目的研究2,3-吲哚醌(2,3-dioxoindoline,ISA)对人神经母细胞瘤细胞SH-SY5Y凋亡和端粒酶表达的影响。方法体外培养人神经母细胞瘤细胞SH-SY5Y细胞,将SH-SY5Y细胞随机分为对照组和ISA不同浓度(0、100、200、400μmol·L-1)处理组,采用Hochest33258荧光染色和琼脂糖凝胶电泳分析细胞凋亡;采用Western blot检测凋亡抑制基因bcl-2、凋亡基因bax蛋白表达的变化;采用RT-PCR检测加药后SH-SY5Y bcl-2,bax及端粒酶逆转录酶(hTERT) mRNA表达水平的变化。结果100、200、400μmol·L-1ISA处理SH-SY5Y细胞48h后,荧光染色可观察到明显的细胞凋亡的核浓缩、核碎裂形态;bcl-2 mRNA及蛋白表达逐渐减少(P<0.05),各组间比较差别有统计学意义;bax mR-NA及蛋白表达水平未见变化(P>0.05);hTERT mRNA表达水平降低(P<0.05),各组间差异比较有统计学意义;200、400μmol·L-1ISA处理SH-SY5Y细胞48h,琼脂糖凝胶电泳可见DNA梯带。结论2,3-吲哚醌可能通过下调bcl-2和hTERT表达诱导SH-SY5Y细胞凋亡,并在一定浓度范围内呈浓度依赖关系。     

A synthetic curcumin derivative hydrazinobenzoylcurcumin induces autophagy in A549 lung cancer cells

Context: Curcumin exhibits growth-suppressive activity against a variety of cancer cells, but low bioavailability restricts its application in chemotherapeutic trials. Nowadays, a growing number of curcumin derivatives or analogs are known, hoping to replace curcumin and circumvent this problem. Hydrazinobenzoylcurcumin (HBC) has been synthesized and identified as a potent inhibitor of cell proliferation in previous reports.

Objective: This study presents a novel mechanism of cell autophagy induced by HBC in the human non-small lung epithelial carcinoma (A549) cells.

Materials and methods: Cells were cultured and treated with HBC at different concentrations (10–80?μM) and at different time periods (1–24?h). Microscopic analysis was used to detect the morphology changes and autophagolysosomes of A549 cells. An acridine orange staining assay was conducted to evaluate the autophagolysosomes and autophagic vacuoles was analyzed by monodansylcadaverine (MDC) and GFP-LC3 transfection analysis. Western blotting was used to assess the conversion of microtubule-associated protein light chain 3 (LC3).

Results: HBC could induce A549 cells autophagolysosomes formation in a dose and time-dependent manner and the inhibitory rate of HBC (80?μM) on the viability of A549 cells reached 76.68?±?5.81% after 24?h of treatment. Autophagic vacuoles increased in a concentration-dependent manner in HBC-treated cell. Furthermore, conversion of LC3-I to LC3-II, accumulation of GFP-tagged LC3 positive intracellular vacuoles and increased fusion of autophagosomes with lysosomes suggested the occurrence of autophagy.

Conclusion: Our data indicate that HBC induced A549 cell autophagy, which is a novel cell death mechanism induced by curcumin derivatives.     

Celastrol induces apoptosis in non-small-cell lung cancer A549 cells through activation of mitochondria- and Fas/FasL-mediated pathways

Celastrol is a natural compound extracted from the traditional Chinese medicinal herb, Tripterygium wilfordii Hook. It has attracted interests for its potential anti-inflammatory and antitumor effects. However, the molecular mechanisms of celastrol-induced apoptosis in cancer cells remain unclear. In this study, we investigated the effects of celastrol on the human non-small-cell lung cancer (NSCLC) cell line A549 in vitro. Celastrol caused a dose- and time-dependent growth inhibition of A549 cells with an IC₅₀ of 2.12 μM at 48 h treatment. Celastrol induced A549 cells apoptosis as confirmed by annexin V/propidium iodide staining and DNA fragmentation. Celastrol-induced apoptosis was characterized by cleavage of caspase-9, caspase-8, caspase-3, and PARP protein, increased Fas and FasL expression, and a reduction in the mitochondrial membrane potential. Furthermore, celastrol induced the release of cytochrome c. Celastrol also up-regulated the expression of pro-apoptotic Bax, down-regulated anti-apoptotic Bcl-2, and inhibited Akt phosphorylation. These results demonstrate that celastrol can induce apoptosis of human NSCLC A549 cells through activation of both mitochondria- and FasL-mediated pathways.     

Ceramide induces apoptosis in human lung adenocarcinoma A549 cells through mitogen-activated protein kinases

AIM: To provide experimental data for further research on the signal transduction of apoptosis in lung adenocarcinoma cells, we examined the effects of exogenous C2-ceramide administration on several members of the mitogen-activated protein kinase (MAPK) superfamily and caspase-3 in A549 cells. METHODS: Cell viability and apoptosis were analyzed by cell counting kit-8 assay and flow cytometry. Various MAPK and caspase-3 proteins were detected by Western blotting. RESULTS: C2-ceramide selectively altered the phosphorylation state of members of the MAPK superfamily, causing hyperphosphorylation of mitogen-activated protein kinase kinase (MEK)1/2 and the p38 MAPK, but not affecting the phosphorylation of extracellular signal-regulated kinase 1/2 and the c-Jun N-terminal kinase. SB-203580 (a p38 MAPK inhibitor) and p38 siRNA, but not U0126 (a MEK inhibitor), partially rescued cell death induced by C2-ceramide. C2-ceramide promoted the activation of caspase-3. CONCLUSION: Exogenous C2-ceramide induced apoptosis in human lung adenocarcinoma A549 cells. The activation of MAPK and caspase-3 were involved in the mechanisms of C2-ceramide-induced apoptosis in A549 cells.     

Indole-3-carbinol induces apoptosis through p53 and activation of caspase-8 pathway in lung cancer A549 cells

Indole-3-carbinol (I3C) has anti-tumor effects in various cancer cell lines. However, the anti-tumor effect of I3C on human lung cancers has been rarely reported. We investigated the anti-tumor effects and its mechanism of I3C on human lung carcinoma A549 cell line. Treatment of the A549 cells with I3C significantly reduced cell proliferation, increased formations of fragmented DNA and apoptotic body, and induced cell cycle arrest at G0/G1 phase. I3C increased not only the protein levels of cyclin D1, phosphorylated p53, and p21 but also the expression of Fas mRNA. Cleavage of caspase-9, -8, -3 and PARP also was increased by I3C. Treatment with wortmannin significantly suppressed both I3C-induced Ser15 phosphorylation and accumulation of p53 protein. The inhibition of caspase-8 by z-IETD-FMK significantly decreased cleavage of procaspase-8,-3 and PARP in I3C-treated A549 cells. Taken together, these results demonstrate that I3C induces cell cycle arrest at G0/G1 through the activation of p-p53 at Ser 15 and induces caspase-8 mediated apoptosis via the Fas death receptor. This molecular mechanism for apoptotic effect of I3C on A549 lung carcinoma cells may be a first report and suggest that I3C may be a preventive and therapeutic agent against lung cancer.     

Monosaccharide digitoxin derivative sensitize human non-small cell lung cancer cells to anoikis through Mcl-1 proteasomal degradation

Advanced stage cancers acquire anoikis resistance which provides metastatic potential to invade and form tumors at distant sites. Suppression of anoikis resistance by novel molecular therapies would greatly benefit treatment strategies for metastatic cancers. Recently, digitoxin and several of its novel synthetic derivatives, such as α-l-rhamnose monosaccharide derivative (D6-MA), have been synthesized and studied for their profound anticancer activity in various cancer cell lines. In this study, we investigated the anoikis sensitizing effect of D6-MA compared with digitoxin to identify their anti-metastatic mechanism of action. D6-MA sensitized NSCLC H460 cells to detachment-induced apoptosis with significantly greater cytotoxicity (IC50 = 11.9 nM) than digitoxin (IC50 = 90.7 nM) by activating caspase-9. Screening of the Bcl-2 protein family revealed that degradation of anti-apoptotic Mcl-1 protein is a favorable target. Mcl-1 over-expression and knockdown studies in D6-MA and digitoxin exposed cells resulted in rescue and enhancement, respectively, indicating a facilitative role for decreased Mcl-1 expression in NSCLC anoikis. Transfection with mutant Mcl-1S159 attenuated detachment-induced cell death and correlated with a remaining of Mcl-1 level. Furthermore, D6-MA suppressed Mcl-1 expression via ubiquitin proteasomal degradation that is dependent on activation of glycogen synthase kinase (GSK)-3β signaling. In addition, D6-MA also targeted Mcl-1 degradation causing an increased anoikis in A549 lung cancer cells. Anoikis sensitizing effect on normal small airway epithelial cells was not observed indicating the specificity of D6-MA and digitoxin for NSCLC. These results identify a novel cardiac glycoside (CG) sensitizing anoikis mechanism and provide a promising anti-metastatic target for lung cancer therapy.     

消瘤1号通过影响bax和bcl-2的表达诱导人乳腺癌细胞MCF-7凋亡

目的：探讨中成药消瘤1号诱导MCF-7人乳腺癌细胞凋亡的作用及其分子机制。方法：采用细胞培养技术,用不同浓度的含药血清（含药物浓度为1、10、100、1 000μg/ml）处理MCF-7细胞,用MTT法检测药物对细胞增殖的影响;以流式细胞仪测定碘化丙啶染色细胞细胞周期的变化;采用实时-PCR法检测bax mRNA和bcl-2 mRNA表达。结果：消瘤1号处理MCF-7细胞后,随着药物浓度增加,作用时间延长,细胞增殖速度减慢。流式细胞仪检测结果显示,消瘤1号使MCF-7细胞阻滞于S期,随着药物浓度的增加,细胞凋亡逐渐增加。消瘤1号还能够促进细胞中bax mRNA表达,减少bcl-2 mRNA表达,并呈浓度依赖性。结论：消瘤1号诱导MCF-7细胞凋亡,其机制涉及bax/bcl-2比值升高,引起线粒体释放细胞色素C。消瘤1号有可能开发为治疗乳腺癌的药物。     

Annosquacin B induces mitochondrial apoptosis in multidrug resistant human breast cancer cell line MCF-7/ADR through selectively modulating MAPKs pathways

Context: Multidrug resistance (MDR) is a major obstacle to efficient therapy of cancers. It is a prime concern for researchers to find compounds with anti-proliferative activity on MDR cell lines. In recent years, annonaceous acetogenins (ACGs) were reported to have anti-proliferative activity. However, the underlying mechanisms are still unknown.

Objective: This study determines the mechanisms of anti-proliferative activity induced by Annosquacin B (AB) against MCF-7/ADR cells.

Material and methods: The cytotoxicity of AB at varying concentrations (0.64, 1.6, 4, 10, 25, 62.5, 156.25?μM) on MCF-7/ADR cells was assessed using the MTT assay. Annexin V-FITC/propidium iodide staining and Acrinidine orange and ethidium bromide (AO/EB) staining were employed to investigate whether AB (14, 7, 3.5?μM) could induce apoptosis in MCF-7/ADR cells. Levels of caspase-3 and caspase-9, Bax, Bcl-2 and MAPKs kinases were evaluated by western blot assay following treatment with various concentrations of AB (3.5, 7, 14?μM) at different time points (0, 0.5, 1, 2, 4, 8, 12?h).

Results and conclusion: MTT assay showed that AB significantly decreased cell viability on MCF-7/ADR (IC₅₀ of 14.69?μM). AB-induced apoptosis in MCF-7/ADR cells through mitochondrial apoptosis pathways. It induced typical apoptosis by morphologic changes; elevate levels of caspase-3, caspase-9 as well as the ratio of Bax/Bcl-2. In addition, AB increased the expression of p-p38 MAPK and decreased the expression of p-JNK, while whether ERK1/2 had an effect on the MCF-7/ADR apoptosis remains to be determined.