食管癌survivin、caspase-3表达与细胞凋亡的关系

目的探讨survivinmRNA、caspase-3蛋白在食管鳞癌中的表达及其与细胞凋亡的关系。方法分别采用RT-PCR和免疫组化技术检测38例食管鳞癌及其对应的正常组织中survivinmRNA和caspase-3蛋白的表达,运用TUNEL方法检测细胞凋亡。结果73.68%食管鳞癌组织呈survivinmRNA阳性表达,显著高于正常组织,并与食管鳞癌的分化程度、临床分期有关,与年龄、性别、淋巴结转移无关;caspase-3蛋白在食管鳞癌和正常组织中的阳性表达率分别为26.32%和89.47%,差异有显著性,并与食管鳞癌的分化程度有关,与年龄、性别、淋巴结转移和临床分期无关;在食管鳞癌组织中,survivinmRNA和Caspase-3蛋白表达呈负相关;survivinmRNA阳性的食管鳞癌组中细胞凋亡指数明显低于survivinmRNA阴性组,(P<0.01),caspase-3蛋白阳性的食管鳞癌组中平均细胞凋亡指数明显高于caspase-3蛋白阴性组(P<0.01)。结论survivin、caspase-3参与了食管鳞癌的发生、发展,可以作为食管鳞癌预后的指标,survivin通过抑制caspase-3的活性而发挥其抑制细胞凋亡的作用是其主要的分子机制。     

Lmcp对子宫内膜癌细胞Survivin蛋白活性的影响

目的:检测低分子柑橘果胶（low modified citrus pectin,Lmcp）对子宫内膜癌细胞株 Ishikawa中凋亡调控因子Survivin蛋白表达的影响。方法:应用Western blot方法检测经不同浓度Lmcp（0、100、300、500 nmol/L）作用不同时间（0、6、12、36 h）后,各组 Ishikawa细胞中Survivin蛋白的表达情况。结果:提高Lmcp作用浓度及延长Lmcp作用时间,均可使Ishikawa细胞中Survivin蛋白的表达减弱。结论:Lmcp可下调子宫内膜癌细胞Ishikawa中存活蛋白 Survivin的表达,且此效果有剂量（0~500 nmol/L）和时间（0~36 h）依赖性。     

Ribozyme-mediated inhibition of survivin expression increases spontaneous and drug-induced apoptosis and decreases the tumorigenic potential of human prostate cancer cells

Survivin is a member of the inhibitor of apoptosis protein (IAP) family, which has been implicated in inhibition of apoptosis and control of mitotic progression. The finding that survivin is overexpressed in most human tumors but absent in normal adult tissues has led to the proposal of survivin as a promising therapeutic target for anticancer therapies. We decided to evaluate the effects of a ribozyme-based strategy for survivin inhibition in androgen-independent human prostate cancer cells. We constructed a Moloney-based retroviral vector expressing a ribozyme targeting the 3' end of the CUA(110) triplet in survivin mRNA, encoded as a chimeric RNA within adenoviral VA1 RNA. Polyclonal cell populations obtained by infection with the retroviral vector of two androgen-independent human prostate cancer cell lines (DU145 and PC-3) were selected for the study. Ribozyme-expressing prostate cancer cells were characterized by a significant reduction of survivin expression compared to parental cells transduced with a control ribozyme; the cells became polyploid, underwent caspase-9-dependent apoptosis and showed an altered pattern of gene expression, as detected by oligonucleotide array analysis. Survivin inhibition also increased the susceptibility of prostate cancer cells to cisplatin-induced apoptosis and prevented tumor formation when cells were xenografted in athymic nude mice. These findings suggest that manipulation of the antiapoptotic survivin pathway may provide a novel approach for the treatment of androgen-independent prostate cancer.     

YM155对肝癌HepG2细胞增殖和凋亡的影响

目的:探讨YM155对肝癌HepG2细胞增殖和凋亡的影响及可能的机制。方法:采用CCK-8法检测细胞生长抑制率；应用流式细胞仪检测细胞凋亡率的变化；Western blot法检测细胞中蛋白表达的变化，实时定量RT-PCR检测survivin mRNA表达的变化。结果:YM155对人肝癌HepG2细胞的生长抑制作用呈现剂量和时间依赖性。流式细胞术结果显示，HepG2细胞凋亡率明显升高,呈现剂量依赖性。YM155可引起survivin mRNA及蛋白表达下降，而caspase-3、caspase-9和PARP蛋白表达上升。结论:YM155可以抑制人肝癌HepG2细胞的增殖并促进其凋亡，其机制可能是通过激活caspase凋亡途径来实现。     

Survivin蛋白在乳腺癌发生、发展不同阶段的表达及意义

背景与目的:Survivin蛋白是新近发现的凋亡抑制因子,主要通过抑制Caspase-3、Caspase-7而阻断细胞凋亡过程,目前研究表明Survivin蛋白在很多恶性肿瘤组织中高表达。本研究通过观察Survivin在正常乳腺组织、乳腺囊性增生组织、乳腺不典型增生组织及乳腺癌组织中的蛋白表达,探讨Survivin在乳腺癌发生、发展中的作用。方法:采用免疫组织化学SP法检测正常乳腺组织(96例)、乳腺囊性增生组织(56例)、乳腺不典型增生组织(12例)及乳腺癌组织(119例)中Survivin蛋白的表达,并分析其和乳腺癌临床病理特征的关系。结果:Survivin蛋白在正常乳腺组织、乳腺囊性增生组织、乳腺不典型增生组织及乳腺癌组织中的阳性率分别为4.2%(4/96)、5.4%(3/56)、42.7%(5/12)、72.2%(86/119),后二者的阳性率明显高于前二者(P<0.005);浸润性非特殊类型乳腺癌Survivin蛋白阳性率(82.0%,73/89)明显高于浸润性特殊型乳腺癌(45.4%,10/22)和早期浸润性乳腺癌(37.5%,3/8)(P<0.05);Survivin蛋白表达在有淋巴结转移的乳腺癌中有升高的趋势,但差异无统计学意义(P>0.05)。结论:Survivin蛋白在乳腺癌发生、发展不同阶段的表达呈进行性上升的趋势,过度表达提示预后不良。     

沉默survivin基因介导口腔表皮癌细胞KB及KBv200凋亡的比较研究

背景与目的:Survivin是IAPs家族的重要成员之一,研究表明可结合凋亡途径中的Caspase-3、Caspase-7、Caspase-9抑制其活性,引起肿瘤细胞的抗凋亡作用,尤其使肿瘤细胞耐受化疗药物诱导的凋亡,与化疗耐药密切相关。survivin在人口腔表皮癌细胞KB及其耐药株KBv200均有表达,本实验拟通过RNAi方法沉默survivin基因比较研究它介导KB和KBv200细胞的凋亡作用。方法:RT-PCR法检测细胞中survivinmRNA水平,流式细胞仪检测细胞中survivin蛋白水平,Hoechst33258荧光染色法观察细胞形态,PI染色结合流式细胞仪法检测细胞凋亡率,以及Caspase-3活性测定试剂盒检测Caspase-3的活性,MTT法测定肿瘤细胞生长情况。结果:KBv200细胞中survivinmRNA和蛋白表达量较高。转染mu6/survivin质粒后48h,KB和KBv200细胞中survivinmRNA表达抑制率分别为(61.98±8.12)%和(59.29±6.32)%,蛋白表达抑制率分别为(44.25±5.26)%和(38.76±4.31)%。转染mu6/survivin质粒后24h、48h、72h,流式细胞仪结果显示KB和KBv200细胞凋亡都明显增加,均在48h凋亡达到高峰,以KB凋亡率较高,并且Caspase-3活性也都明显增加,均在48h达到最高。同时KB细胞生长抑制率分别为(33.04±2.17)%、(56.25±3.32)%和(58.26±5.15)%,KBv200细胞生长抑制率则分别为(35.23±3.43)%、(44.90±4.12)%和(44.19±4.37)%。结论:siRNA方法能够有效沉默survivin基因,不仅能诱导KB细胞凋亡,而且能介导耐药株KBv200细胞凋亡。     

survivin抗肺癌细胞凋亡的分子机制

目的 研究survivin反义寡核苷酸（ASODN）诱导肺癌细胞凋亡的作用,探讨survivin抗肺癌细胞凋亡的分子机制。方法 在脂质体介导下,分别以100mmol／L、300mmol／L和500mmol／L浓度的survivin ASODN,作用于肺癌细胞株NCI-H44624h、48h和72h后,用RT-PCR和Western blot检测survivin mRNA及蛋白表达,流式细胞仪（FCM）检测细胞凋亡;Rh123染色法检测细胞线粒体膜电位（△ψm）变化;ELISA法检测胞浆细胞色素C（cyt C）浓度;比色法检测胞浆内天冬氨酸特异性半胱氨酸蛋白酶-9（caspase-9）、caspase-3的活性;Western blot检测caspase-8蛋白表达;加入环孢霉素A（CsA）后,以FCM检测细胞凋亡。结果 与各对照组相比,survivin ASODN显著下调了survivin mRNA表达,且呈时间和浓度依赖性,其中以500mmol／L作用72h时效果最佳,抑制率达62．7％,其蛋白表达也显著下调。NCI-H446细胞的凋亡指数（AI）为48．35％,明显高于对照组（3．75％）、空脂质体组（3．41％）、无义寡核苷酸（NSODN）组（4．69％）、100和300mmol／LASODN组（19．85％和34．39％）;增殖指数（PI）为24．38％,明显低于上述各组（75．54％、73．12％、71．76％、51．03％和38．94％,P均〈0．01）。survivin ASODN导致细胞△ψm逐渐下降,并相继引起cytc的释放、caspase-9和caspase-3的激活,而caspase-8酶原无变化。CsA显著抑制了survivin ASODN诱导的细胞凋亡。结论 survivin通过调控线粒体凋亡途径发挥抗肺癌细胞凋亡作用;survivin ASODN能够显著下调survivin mRNA及蛋白表达,诱导肺癌细胞凋亡,抑制细胞增殖。     

Survivin在乳腺癌中的表达及其与Caspase-3、PCNA表达的关系

目的探讨Survivin在乳腺癌发生、发展中的作用及其与Caspase-3蛋白表达和细胞增殖的相互关系.方法用免疫组化S-P法检测Survivin在正常乳腺组织(10例)、乳腺囊性增生组织(18例)、不典型增生组织(20例)和乳腺癌组织(50例)中的表达以及Caspase-3、PCNA在乳腺癌组织中的表达.结果Survivin蛋白在正常乳腺组织无表达,在乳腺囊性增生组织、不典型增生组织、乳腺癌组织中的阳性率分别为5.6%(1/18)、45.0%(9/20)、72.0%(36/50),差异有显著性(P＜0.05).Survivin蛋白的表达与临床分期和淋巴结转移有关(P＜0.05),与年龄、是否绝经、肿瘤大小和组织学分级均无关.Survivin与Caspase-3的表达呈负相关(P＜0.01).Survivin蛋白表达阳性的乳腺癌PCNA的标记指数明显高于Survivin蛋白表达阴性的乳腺癌细胞PCNA的标记指数(P＜0.01).结论Survivin蛋白在乳腺癌中表达上调,提示其通过抑制凋亡在乳腺癌发生、发展中起重要作用,可能成为乳腺癌基因治疗的新靶点.Survivin通过与激活的Caspase-3结合,抑制其活性,从而阻止细胞凋亡.Survivin不仅参与凋亡的调控,还促进了细胞增殖.     

Therapeutic targeting of the survivin pathway in cancer: initiation of mitochondrial apoptosis and suppression of tumor-associated angiogenesis.

PURPOSE: Molecular antagonists of the inhibitor of apoptosis protein survivin have shown promise as novel anticancer strategies for triggering tumor cell apoptosis, dysregulating mitotic progression, and inhibiting tumor growth in preclinical models. However, how survivin couples to the cell death machinery has remained elusive, and the relevant cellular targets of survivin antagonists have not been completely elucidated. Experimental Design: Human umbilical vein and dermal microvascular endothelial cells were infected with replication-deficient adenoviruses encoding survivin (pAd-Survivin), green fluorescent protein (pAd-GFP), or a phosphorylation-defective survivin Thr(34)-->Ala (pAd-T34A) dominant negative mutant. The effect of wild-type or mutant survivin was investigated on capillary network stability, endothelial cell viability, and caspase activation in vitro and on kinetics of tumor growth and development of angiogenesis in a breast cancer xenograft model in vivo. The cell death pathway initiated by survivin targeting was mapped with respect to cytochrome c release, changes in mitochondrial transmembrane potential, and apoptosome requirements using mouse embryonic fibroblasts deficient in Apaf-1 or caspase-9. RESULTS: Adenoviral transduction of endothelial cells with pAd-Survivin inhibited growth factor deprivation- or ceramide-induced apoptosis, reduced caspase-3 and -7 generation, and stabilized three-dimensional capillary networks in vitro. Conversely, expression of pAd-T34A caused apoptosis in umbilical vein and dermal microvascular endothelial cells and resulted in caspase-3 activity. Cell death induced by survivin targeting exhibited the hallmarks of mitochondrial-dependent apoptosis with release of cytochrome c and loss of mitochondrial transmembrane potential and was suppressed in Apaf-1 or caspase-9 knockout mouse embryonic fibroblasts. When injected in human breast cancer xenografts, pAd-T34A inhibited growth of established tumors and triggered tumor cell apoptosis in vivo. This was associated with a approximately 60% reduction in tumor-derived blood vessels by quantitative morphometry of CD31-stained tumor areas, and appearance of endothelial cell apoptosis by internucleosomal DNA fragmentation in vivo. CONCLUSIONS: Survivin functions as a novel upstream regulator of mitochondrial-dependent apoptosis, and molecular targeting of this pathway results in anticancer activity via a dual mechanism of induction of tumor cell apoptosis and suppression of angiogenesis.     

Survivin, a member of the inhibitor of apoptosis family, is induced by photodynamic therapy and is a target for improving treatment response

We observed that photodynamic therapy (PDT) induces the expression and phosphorylation of the inhibitor of apoptosis (IAP) protein survivin in murine and human cancer cells and tumors. Survivin inhibits caspase-9, blocks apoptosis, and is associated with resistance to chemotherapy and radiation. Survivin is a client protein for the 90-kDa heat shock protein (Hsp-90), and the binding of survivin to Hsp-90 assists in the maturation, proper folding, assembly, and transport of this IAP protein. A derivative of the antibiotic geldanamycin, 17-allylamino-17-demethoxygeldanamycin (17-AAG), interferes with proper binding of client proteins, such as survivin, to Hsp-90 and leads to misfolding of client proteins, ubiquination, and proteasome degradation. We hypothesized that PDT efficacy may be reduced by treatment-mediated expression and phosphorylation of survivin, and therefore, targeting the survivin pathway could increase PDT responsiveness. To address this hypothesis, we examined cellular and molecular responses following exposure to PDT, 17-AAG, and the combination of PDT plus 17-AAG in human BT-474 breast cancer cells using Photofrin and NPe6 as photosensitizers. Cells treated with the combination of PDT and 17-AAG exhibited decreased expression of the Hsp-90 client proteins phosphorylated survivin, phosphorylated Akt, and Bcl-2. The decreased expression of these client proteins was accompanied by higher apoptotic indexes and increased cytotoxicity. To confirm a specific role for survivin in modulating PDT, we used a human melanoma cell line, YUSAC2/T34A-C4, stably transfected with an inducible dominant-negative survivin gene under the control of a tetracycline-regulated (tet-off) promoter. PDT treatment of melanoma cells expressing the dominant-negative survivin resulted in increased cleavage of the caspase substrate poly(ADP-ribose) polymerase, apoptosis, and cytotoxicity when compared with results following PDT of the same melanoma cell line expressing wild-type survivin. These results show for the first time that targeting survivin and possibly other Hsp-90 client proteins improves in vitro PDT responsiveness and suggest that manipulation of the antiapoptotic pathway maintained by survivin may enhance PDT-mediated cancer therapy.     

Survivin expression correlates with clinical stage,histological grade,invasive behavior and survival rate in endometrial carcinoma

Survivin is a new member of the inhibitor of apoptosis family of anti-apoptotic proteins. It has been reported that survivin is expressed during fetal development and in cancer tissues. Because suppression of apoptosis is important for carcinogenesis and tumor growth, we investigated the expression of survivin in human endometrial carcinomas. We analyzed serial frozen sections for survivin protein expression in 31 cases of endometrial carcinoma and 20 cases of normal endometria by fluorescent immunohistochemistry. We analyzed the relationship between the percentages of survivin-stained cells and the patient's characteristics, including clinical stage, histological grade, presence of invasion to >1/2 myometrium, clinical outcome, and survival rate. Survivin was weakly detected in some normal endometria in the proliferative phase (0-5.1%) and in the secretory phase (0-15.8%). There was, however, abundant survivin immunoreactivity in the nucleus and/or cytoplasm of the endometrial carcinoma cells. Scoring on the basis of the percentage of positive cells indicated that survivin expression was significantly associated with proliferating cell nuclear antigen-labeling index, clinical stage, histological grade, the presence of invasion to >1/2 myometrium, clinical outcome, and survival rate (P<0.01, respectively). We conclude that the survivin protein is a defining diagnostic marker for endometrial carcinomas that may also yield prognostic information.     

人非小细胞肺癌组织中Survivin的表达及与caspase-3和p21WAF1表达的意义

目的:探讨非小细胞肺癌(nonsmallcelllungcancer,NSCLC)组织中survivin、caspase3和p21WAF1的蛋白表达与临床病理指标的关系及survivin与caspase3和p21WAF1蛋白表达之间的关系。方法:在87例NSCLC原发灶中应用免疫组织化学SP法检测survivin、caspase3和p21WAF1蛋白的表达。结果:在87例NSCLC原发灶中survivin、caspase3和p21WAF13种蛋白表达阳性率分别为71.26%、64.37%和48.28%。它们均与组织学类型无关,P>0.05,而与淋巴结转移均显著相关,P<0.05;survivin和caspase3的蛋白表达与肿瘤细胞分化程度无关,P>0.05,但p21WAF1与肿瘤细胞分化程度显著相关,P=0.003。在87例NSCLC中,survivin的表达与caspase3(P=0.001)和p21WAF1均呈显著负相关,P=0.000。结论:Survivin、caspase3和p21WAF1均与NSCLC的浸润进展显著相关。Survivin可能直接作用于caspase3阻断了细胞的凋亡过程,或通过抑制p21WAF1的表达而缩短了细胞周期,从而促进了NSCLC的癌细胞不断增殖。     

YM155对骨肉瘤细胞系F5M2增殖和凋亡的影响

目的:探讨YM155对人骨肉瘤细胞系F5M2的作用及其机制.方法:体外培养人骨肉瘤细胞系F5M2,不同浓度YM155处理人骨肉瘤细胞系F5M2,用MTT法检测其对细胞增殖的影响;流式细胞仪检测细胞凋亡率;实时荧光定量PCR检测survivin mRNA的表达;蛋白免疫印迹法检测survivin、caspase-3蛋白的表达.结果:YM155可抑制人骨肉瘤细胞F5M2的增殖,且呈剂量依赖性.随着YM155浓度的升高,人骨肉瘤细胞F5M2凋亡率明显增加,同时能够降低survivin在 mRNA水平和蛋白水平的表达,以及激活caspase-3.结论:YM155能够有效抑制人骨肉瘤细胞F5M2增殖,并诱导其凋亡,其可能机制为下调骨肉瘤细胞系F5M2 survivin的表达,继而激活caspase凋亡信号通路.     

Apoptotic effects of signal transduction inhibitors on human tumor cells with different PTEN expression

An important mechanism of antitumoral targeted therapies is the induction of apoptosis in tumor cells. Tamoxifen and trastuzumab (Herceptin), respectively, are able to trigger apoptosis in human breast cancer cells. But, frequently altered apoptotic signal cascades, for instance through PTEN mutations, help tumor cells to escape antitumoral therapy. We studied to what extent the apoptotic effect of signal-transduction inhibitors is dependent on PTEN expression. PTEN expression was analysed by Western blot analysis in tumor cell lines of the breast (BT-474, MCF-7, MDA-MB-231), ovary (BG-1, SK-OV-3) and endometrium (Ishikawa, HEC-1A). Apoptotic effects of tamoxifen, trastuzumab, ZD1839 (Iressa) and different mitogen-activated protein kinase (MAP) inhibitors were measured after 24 h of treatment. Cellular apoptosis was determined by the detection of cytoplasmic histone-DNA complexes. The tested tumor cell lines exhibited a different PTEN expression, ranging from a high expression (ovarian cancer cell line BG-1 and BT-474 breast cancer cells) to a total absence of PTEN expression (endometrial Ishikawa cells). The apoptotic effect of receptor-targeting drugs (tamoxifen, trastuzumab, ZD1839) was dependent both on receptor expression and PTEN expression. When cells were treated with MAPK inhibitors, no correlation between PTEN expression and the apoptosis rate was observed. Our data underline the importance of PTEN expression regarding the induction of apoptosis through various targeted therapies.     

靶向survivin基因siRNA对宫颈癌细胞放射敏感性影响的实验 

 目的 探讨survivin表达对宫颈癌放射敏感性的影响。 方法 RT-PCR和Western blot法分析survivin基因mRNA和蛋白的表达, 平板集落形成实验检测细胞 增殖,流式细胞术检测细胞凋亡率。 survivin siRNA转染HeLa细胞,比较survivin siRNA对细胞凋亡、增殖以及放射敏感性的 影响。 结果 在宫颈癌HeLa细胞中存在survivin的表达,survivin siRNA可诱导HeLa细胞凋亡并抑制增殖 。 结论 survivin siRNA可通过影响细胞凋亡和增殖来增加HeLa细胞的放射敏感性     

Survivin、caspase-3在非霍奇金淋巴瘤组织中的表达及意义

背景与目的:Survivin是新近发现的凋亡抑制因子,在肿瘤的发生中起重要作用。Survivin在多种肿瘤组织广泛表达而在正常成人组织不表达,可直接抑制caspase-3和caspase-7活性。本研究旨在通过检测survivin、caspase-3蛋白在不同恶性度非霍奇金淋巴瘤(non-Hodgkinslymphoma,NHL)组织中的表达,探讨二者与NHL发病的关系及其临床意义。方法:应用免疫组织化学EnVisionsystem法检测NHL患者组织标本survivin、caspase-3蛋白的表达。结果:Survivin及caspase-3在54例NHL中的阳性率分别为51.9%(28/54)和83.3%(45/54)。Survivin在低度恶性组NHL中的表达(19.0%,4/21)低于中-高度恶性组(72.7%,24/33),两组之间有显著性差异(P<0.05);caspase-3表达也有同样规律。Survivin及caspase-3的共同表达率为46.3%(25/54)。结论:NHL中有survivin过度表达。     

Effects of matrine in combination with cisplatin on liver cancer

Matrine, an alkaloid isolated from Sophora flavescens, promotes tumor cell apoptosis and strengthens the anticancer capacity of chemotherapeutic drugs. The present study aimed to investigate the inhibitory effect and underlying mechanism of matrine in combination with cisplatin on liver cancer progression. Tumor progression was studied in nude mice. The human liver cancer cell line HepG2 was injected into BALB/c nude mice subcutaneously to establish a tumor model. Mice were subsequently treated with matrine, cisplatin, matrine + cisplatin or normal saline. Nude mice and tumor growth were monitored. Tumors were excised and the expression of survivin, caspase-3, caspase-7 and caspase-9 was detected by immunohistochemistry. Western blotting was used to determine the expression of survivin, caspase-3, caspase-7, caspase-9 and X-linked inhibitor of apoptosis protein (XIAP) in tumor tissues. The results demonstrated that matrine exerted anticancer effects in liver cancer-transplanted tumors, as evidenced by decrease in tumor weight and volume. Furthermore, the tumor inhibition rate in mice treated with matrine + cisplatin was 83.3%, whereas it was of 37.5 and 75% in mice treated with matrine or cisplatin alone, respectively. In addition, the expression of survivin and XIAP was significantly downregulated, whereas the expression of caspase-3, caspase-7 and caspase-9 was significantly upregulated in tumor tissues from nude mice treated with matrine + cisplatin, compared with those treated with cisplatin, matrine or normal saline. These findings suggested that the combination of matrine and cisplatin may promote tumor cell apoptosis in liver cancer by activating the caspase apoptosis pathway and suppressing the survivin-associated inhibition of caspase-9.     

Non-steroidal anti-inflammatory drugs inhibit cellular proliferation and upregulate cyclooxygenase-2 protein expression in endometrial cancer cells

We determined the effects of several non-steroidal anti-inflammatory drugs (NSAIDs), aspirin (acetylsalicylic acid, ASA), indomethacin and a cyclooxygenase-2 (COX-2)-selective inhibitor (NS398), on cellular proliferation and regulation of COX-2 protein expression in endometrial cancer cells in vitro, and investigated their modes of action. All three NSAIDs markedly inhibited the proliferation of Ishikawa, HEC-1A and AN3CA endometrial cancer cell lines in a time- and concentration-dependent manner. ASA and indomethacin triggered apoptosis in cells of all three lines through release of cytosolic cytochrome c, activation of caspase-9 and-3, and cleavage of poly(ADP-ribose) polymerase (PARP), but NS398 induced minimal apoptosis only in Ishikawa cells. ASA altered the cell cycle distribution, with G2/M phase accumulation of cells, and induced overexpression of Ki-67 protein. Both ASA and indomethacin reduced the protein levels of Bcl-2 and Bcl-xl, but upregulated those of Bax and Bcl-xs. COX-2 protein expression and PGE(2) production were upregulated by ASA and indomethacin in all three cell lines. However, NS398 did not alter COX-2 protein expression or PGE(2) production in these cells. These results indicate that NSAIDs inhibit proliferation of endometrial cancer cells independently of the reduction of COX-2 protein expression. A cytochrome c-dependent apoptotic pathway and/or cell cycle arrest may contribute to the inhibitory effects of these NSAIDs.