FoxM1靶向调控bcl-2促进急性髓系白血病发生

目的:探讨叉头框蛋白M1(Fox M1)及其调控的原癌基因B细胞白血病/淋巴瘤-2(bcl-2)在急性髓系白血病(AML)发生中的作用。方法:RT-q PCR和免疫荧光方法检测17例AML初诊患者、17例治疗后达完全缓解(CR)患者、17例难治复发(RR)患者和15例正常骨髓标本中Fox M1的m RNA和蛋白表达;转染Fox M1 si RNA和对照si RNA至白血病HL60细胞和K562细胞,观察Fox M1对细胞生长和克隆形成的影响,流式细胞术检测Fox M1对凋亡的影响,RT-q PCR和Western blot法检测Fox M1对Bcl-2表达的影响,双萤光素酶活性实验检测Fox M1是否可以靶向作用于bcl-2启动子区域进而影响Bcl-2的表达。结果:AML初诊患者骨髓标本的Fox M1表达较正常对照显著升高,CR患者的Fox M1表达较初诊组降低,RR组的Fox M1表达较初诊组进一步升高。转染Fox M1 si RNA沉默HL60细胞和K562细胞的Fox M1表达后,细胞生长速率显著下降,细胞克隆形成能力显著降低,细胞凋亡率显著升高,bcl-2表达降低,Fox M1可靶向调控bcl-2。结论:初步证实Fox M1可通过靶向调控bcl-2促进AML发生发展,干扰Fox M1表达可抑制细胞增殖并促进细胞凋亡,提示Fox M1是治疗AML的潜在靶标。     

硼替佐米上调fas、bcl2l12、caspase-9和caspase-3基因表达

目的： 探讨硼替佐米诱导慢性粒细胞白血病细胞株K562细胞凋亡及新基因bcl2l12在其中的作用。方法: MTT比色法观察硼替佐米对K562细胞的生长抑制作用;Annexin-V标记和线粒体跨膜电位（Δψm）分析细胞凋亡;RT-PCR方法检测0、6、12和24 h fas、bcl2l12、bcl-2、 bim、bax、caspase-3和caspase-9基因表达变化。结果: 硼替佐米抑制K562细胞生长呈时间和剂量依赖性,24 h和48 h半数抑制浓度分别为161.41 nmol/L和96.33 nmol/L;硼替佐米诱导K562细胞凋亡,12 h Annexin-V阳性细胞就开始增高,并呈时间依赖性,Δψm减低;RT-PCR显示fas、bcl2l12、caspase-3和caspase-9表达增高,但bcl-2、bim和bax表达无明显改变。结论: 硼替佐米可以抑制K562生长并诱导凋亡,上调fas、bcl2l12,使线粒体膜电位下降,激活caspase-9和caspase-3基因,促使DNA发生断裂可能是其诱导凋亡的机制之一。     

沉默HIF-1α基因表达对大鼠肝癌细胞增殖的影响

 目的： 探讨沉默缺氧诱导因子　1α（HIF-1α）基因表达对缺氧状态下肝癌细胞增殖的影响。方法：选用大鼠CBRH-7919肝癌细胞株作为研究对象,利用氯化钴（CoCl2）建立缺氧模型。制备3组特异性较强的HIF-1α siRNA-脂质体复合物,转染于肝癌细胞。利用real-time RT-PCR、Western blotting等方法分别检测肝癌细胞HIF-1α、血管内皮生长因子(VEGF)、p21和cyclin D1在mRNA和（或）蛋白水平的表达。MTT及BrdU 掺入实验检测细胞增殖的变化。结果：缺氧条件下,肝癌细胞的HIF-1α和VEGF mRNA及蛋白表达显著增多（P<0.05）。HIF-1α基因表达沉默后,HIF-1α、VEGF及cyclin D1 mRNA和（或）蛋白表达明显减少（P<0.05）,p21蛋白表达明显增加（P<0.05）。HIF-1α siRNA转染组的BrdU阳性细胞比例明显少于对照组(P<0.05)。结论：沉默HIF-1α基因表达对缺氧状态下肝癌细胞的增殖有显著抑制作用。     

Analysis of mTOR inhibition-involved pathway in ovarian clear cell adenocarcinoma

This study was designed to clarify the mechanism of the mammalian target of rapamycin (mTOR)-hypoxia inducible factor-1 (HIF-1) pathway using the cultured cell strain derived from human ovarian clear cell adenocarcinoma (CCA). Everolimus (a derivative of rapamycin)-treated cells and non-treated cells did not show any difference in mTOR expression. But, phosphorylated-mTOR (p-mTOR) expression significantly decreased in the treated cells, and mTOR-related factors such as phosphorylated-4E-BP1 (p-4E-BP1), HIF-1α, and vascular endothelial growth factor (VEGF) in the downstream region of mTOR revealed a marked decrease in expression. The analysis of influences of the drug on the HIF-1α degradation system showed an increase in von-Hippel Lindau (VHL) expression in the treated cells. Increase of cleaved caspase-3, one of key factors involved in apoptosis, was also shown in the treated cells. In the next step, using nude mice implanted with RMG-1 cells, a decrease in tumor size was demonstrated in 4 of the 7 mice which were orally administered with everolimus. As a result, it was suggested that everolimus administration would be helpful as an anti-tumor therapy for CCA not only via down-regulation of p-mTOR but also degradation of HIF-1α by VHL and induction of apoptosis by cleaved caspase-3.     

黄芩苷抑制CA46细胞增殖和诱导凋亡的作用机制探讨

目的： 研究中药黄芩苷（baicalin）对人Burkitt淋巴瘤细胞株CA46细胞增殖、凋亡的影响并探讨其可能作用机制。 方法：应用MTT法绘制细胞生长曲线观察黄芩苷对CA46细胞增殖的影响;Annexin V-FITC/PI双染流式细胞术、细胞DNA片段化、TdT酶介导的原位缺口末端标记(TUNEL)法检测黄芩苷诱导CA46细胞凋亡的能力;RT-PCR法检测黄芩苷作用前后c-myc、bcl-2 mRNA表达水平的变化,Western blotting法检测c-Myc、Bcl-2、procaspase-3(caspase-3前体)、PARP(多聚ADP核糖聚合酶)蛋白水平的变化。结果：细胞生长曲线结果显示黄芩苷能明显抑制CA46细胞增殖,半数抑制浓度(IC50)约为10 μmol/L;Annexin V-FITC/PI双染流式细胞术早期凋亡的检出、TUNEL晚期凋亡细胞的检出和细胞DNA片段化凋亡梯带的检出,均证实黄芩苷能有效诱导CA46细胞凋亡,细胞凋亡率呈现浓度依赖性递增。黄芩苷作用后CA46细胞c-myc、bcl-2 mRNA和c-Myc、Bcl-2、procaspase-3、PARP(116 kD)蛋白的表达呈现时间依赖性递减,而PARP(85 kD)表达呈现时间依赖性递增。结论：黄芩苷能有效抑制CA46细胞增殖,诱导其凋亡;c-Myc、Bcl-2表达水平下调和caspase-3激活可能参与了这一作用过程。     

CXCR4 siRNA通过抑制STAT3信号通路抑制肺癌细胞活力

目的:初步探索CXC趋化因子受体4(CXCR4)与人肺癌NCI-H292细胞活力和凋亡的关系及其作用机制。方法:采用RNA干扰技术沉默肺癌细胞中CXCR4基因的表达,将CXCR4小干扰RNA(siRNA-CXCR4)转染至NCI-H292细胞中,分为空白对照组(未转染的细胞)、阴性对照组(转染无关序列RNA)和siRNA-CXCR4组(转染siRNA-CXCR4),使用信号转导子及转录激活子3(STAT3)抑制剂NSC 74859作用于已转染肺癌细胞48 h,观察细胞的活力、凋亡及磷酸化STAT3(p-STAT3)水平的变化,用CCK-8实验检测干扰CXCR4基因表达对细胞活力的影响,流式细胞术检测细胞的凋亡率,采用Western blot检测CXCR4、STAT3、p-STAT3、细胞周期蛋白D1(cyclin D1)、cleaved caspase-3和多聚ADP-核糖聚合酶1(PARP-1)的蛋白水平。结果:Western blot检测结果显示siRNACXCR4组细胞中CXCR4蛋白的表达量显著低于对照组(P0.05)。干扰CXCR4表达显著抑制细胞的活力(P0.05),促进其凋亡(P0.05),显著增加cleaved caspase-3和PARP1的蛋白水平。siRNA-CXCR4组细胞中STAT3、p-STAT3和cyclin D1的蛋白水平显著降低(P0.05);加入STAT3抑制剂后细胞中p-STAT3蛋白水平和细胞活力显著低于siRNA-CXCR4组(P0.05),凋亡率显著增加(P0.05)。结论:CXCR4通过调控STAT3信号通路介导下游靶基因的表达,参与肺癌细胞的生长、凋亡。这一结果为肺癌的治疗提供了新的治疗靶点。     

TPX2对人肺癌细胞增殖、凋亡及cleavedcaspase-3表达的影响

目的 探讨Xklp2靶蛋白(TPX2)对人肺癌细胞增殖、凋亡及活化的半胱氨酸天冬氨酸蛋白酶3(cleaved caspase-3)表达影响。方法 培养人肺癌细胞A549,分为Control组(不进行细胞转染)、siRNA-NC组(细胞转染TPX2 siRNA control)、TPX2 siRNA组(细胞转染TPX2 siRNA),采用实时荧光定量PCR (qPCR)和Western blot检测TPX2 siRNA的转染效果。取转染后各组细胞,采用噻唑蓝检测细胞增殖情况,流式细胞术检测细胞凋亡情况,Western blot检测cleaved caspase-3蛋白表达情况。结果 TPX2 siRNA组中,TPX2 mRNA、蛋白水平和细胞光密度(OD)值均明显低于Control组和siRNA-NC组,细胞凋亡率、细胞中cleaved caspase-3蛋白表达水平均明显高于Control组和siRNA-NC组,差异均有统计学意义(P值均<0.05);而siRNA-NC组中,TPX2 mRNA、蛋白水平及细胞OD值、细胞凋亡率、细胞中cleaved caspase-3与Control组比较,差异均无统计学意义(P值均＞0.05)。结论TPX2 siRNA能够干扰人肺癌细胞A549中TPX2的表达。下调TPX2的表达能够抑制人肺癌细胞A549增殖,促进caspase-3活化,促进人肺癌细胞A549的凋亡。     

Genome-wide expression analysis of Middle Eastern colorectal cancer reveals FOXM1 as a novel target for cancer therapy

To identify genes potentially playing an important role in the progression of colorectal carcinoma (CRC), we screened global gene expression using cDNA expression array on 41 CRC tissue samples and 25 noncancerous colorectal tissue samples. Among the up-regulated genes, forkhead box M1 (FOXM1) has been shown to play a critical role in pathogenesis of various malignancies. Using immunohistochemistry on 448 Saudi CRC samples in tissue microarray format, FoxM1 protein overexpression was seen in 66% of CRC tissues and was significantly associated with poorly differentiated and highly proliferative tumors (P = 0.0200 and 0.0018, respectively). FoxM1 expression was also significantly associated with MMP-9 protein expression (P = 0.0002). In vitro data using CRC cell lines showed that inhibition of FoxM1 by thiostrepton resulted in inhibition of proliferation and induction of apoptosis in a dose-dependent manner. Overexpression of FoxM1 potentiated cell proliferation, cell transformation, and migration/invasion of CRC cells via up-regulation of FoxM1 target genes MMP2 and MMP9 and protected these cells from thiostrepton-mediated antiproliferative effects. Finally, in vivo, overexpression of FoxM1 promoted growth of CRC-cell line xenograft tumors in nude mice. Altogether, our data indicate that FoxM1 signaling contributes to aggressiveness in a subset of CRC and that the FOXM1 gene may serve as a useful molecular biomarker and potential therapeutic target.     

沉默FoxM1通过促进线粒体释放细胞色素C诱导口腔鳞癌细胞凋亡

目的:研究沉默叉头框蛋白M1 (FoxM1)基因对口腔鳞癌细胞凋亡影响及机制。方法:口腔鳞癌SCC9细胞感染FoxM1-shRNA慢病毒或阴性对照慢病毒,用RT-qPCR和Western blot测定沉默效果。MTT法测定细胞活力变化,平板克隆实验测定细胞克隆形成能力变化,流式细胞术测定细胞凋亡变化,Western blot测定细胞中cleaved caspase-3和cleaved caspase-9蛋白水平变化,JC-1法测定细胞线粒体膜电位变化,Western blot测定细胞线粒体和胞浆中细胞色素C(cytochrome C)蛋白水平的变化。结果:FoxM1-shRNA慢病毒感染成功下调口腔鳞癌细胞中FoxM1的表达(P0.05),阴性对照慢病毒对细胞中FoxM1表达水平没有影响。沉默FoxM1的口腔鳞癌细胞活力降低(P0.05),细胞克隆形成能力也降低(P0.05),细胞凋亡率及cleaved caspase-3和cleaved caspase-9蛋白水平均升高(P0.05),线粒体膜电位降低(P0.05),胞浆中cytochrome C蛋白水平升高(P0.05),线粒体中cytochrome C蛋白水平降低(P0.05)。结论:沉默FoxM1可以通过降低口腔鳞癌细胞线粒体膜电位、促进线粒体释放cytochrome C而诱导细胞凋亡。     

阿帕替尼通过阻断VEGF通路增强胃癌放疗疗效

目的:探讨血管内皮生长因子(VEGF)受体2酪氨酸激酶抑制剂阿帕替尼对胃癌细胞株SGC-7901放疗疗效的影响及其可能机制。方法:试验设对照组、阿帕替尼组、单纯放疗组与联合组。CCK-8法检测细胞活力,流式细胞术分析细胞凋亡比例与细胞周期,免疫荧光染色观察细胞核内γ-H_2AX的表达,Western blot法检测细胞增殖和凋亡相关蛋白。结果:与阿帕替尼组或单纯放疗组相比,阿帕替尼联合X射线显著降低SGC-7901细胞的生长活力(P0.01),增殖相关蛋白p-PLCγ1和p-ERK1/2的水平下降;细胞凋亡比例明显升高(P0.01),凋亡相关蛋白PARP、cleaved caspase-9和cleaved caspase-3蛋白水平上调,Bcl-2表达下降;SGC-7901细胞核内γ-H_2AX焦点淬灭延迟,表明阿帕替尼干扰放射线诱导的DNA双链断裂的修复;SGC-7901 G_2期细胞比例显著增高(P0.01)。结论:阿帕替尼通过阻断VEGF通路增加胃癌细胞对X射线照射的敏感性。     

沉默NANOG表达对人肝癌细胞HepG2中cyclin D1表达及细胞增殖的影响

 目的:探讨RNA干扰沉默NANOG表达后对肝癌细胞HepG2中细胞周期素D1(cyclin D1)表达及细胞增殖的影响。方法:将以NANOG基因为靶点的NANOG-siRNA瞬时转染肝癌细胞HepG2,real-time PCR和Western boltting检测NANOG、cyclin D1 mRNA和蛋白的表达,CCK-8和平板克隆形成实验检测细胞增殖能力,流式细胞术检测细胞周期情况。结果:与mock组比较,转染NANOG-siRNA后,肝癌细胞HepG2中NANOG、cyclin D1 mRNA和蛋白水平均下调(P＜0.05),细胞增殖能力下降(P＜0.05),进入G 0/G 1期的细胞比例增多(P＜0.05)。结论:沉默NANOG表达可引起肝癌细胞HepG2中cyclin D1的表达下降,导致细胞增殖能力下降。     

Immunohistochemical analysis of cleaved caspase-3 detects high level of apoptosis frequently in diffuse large B-cell lymphomas of the central nervous system

The purpose of the present paper was to examine the level of apoptosis and the relationships among apoptosis, apoptosis-associated proteins, and proliferating potential in lymphoma tissues to clarify the characteristics of apoptosis in diffuse large B-cell lymphomas (DLBCL) of the central nervous system (CNS). The formalin-fixed, paraffin-embedded tissues of CNS and non-CNS DLBCL (20 cases each) were studied by terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) and immunohistochemistry, using antibodies against single-stranded DNA (ssDNA), cleaved caspase-3, bcl-2, bax, p53, Fas and Ki-67. The cleaved caspase-3 immunohistochemistry detected apoptosis of the lymphoma cells most sensitively compared to TUNEL and ssDNA immunohistochemistry. High expression (grade + + or + + +) of cleaved caspase-3 was found more frequently in CNS DLBCL (11 cases, 55%) than non-CNS DLBCL (three cases, 15%; P = 0.009). Bax-positivity of lymphoma cells was increased in six cases of CNS DLBCL, which also showed high positivity of cleaved caspase-3. There was no significant correlation between the cleaved caspase-3-positivity and the Ki-67 positivity. The present study indicates that the number of apoptotic cells and expression level of cleaved caspase-3 were significantly higher in CNS DLBCL than non-CNS DLBCL, and that the correlation of bax and cleaved caspase-3 expression was often present in CNS DLBCL.     

二苯乙烯苷对同型半胱氨酸诱导血管内皮细胞凋亡及bcl-2、bax、caspase-3表达的影响

 目的：研究何首乌二苯乙烯苷（TSG）对同型半胱氨酸（Hcy）诱导人脐静脉内皮细胞（HUVECs）凋亡及bcl-2、bax和caspase-3 mRNA表达的影响。方法：建立Hcy （3 mmol/L）所致培养HUVECs核损伤模型,TSG（1和10 μmol/L）提前2 h预孵育,然后再以Hcy处理,作为TSG保护组。用Hoechst 33342核染色法观察HUVECs细胞核损伤状态,以流式细胞术检测细胞凋亡情况,用实时荧光定量RT-PCR法检bcl-2、bax和caspase-3 mRNA的表达。结果：经3 mmol/L Hcy处理后,与正常培养的细胞相比,HUVECs核损伤加重,凋亡细胞比例升高,bcl-2表达降低（P＜0.01）,bax和caspase-3表达增加（P＜0.01）。TSG 1 μmol/L和10 μmol/L预孵育后再经3 mmol/L Hcy处理,与单经3 mmol/L Hcy损伤模型组相比,HUVECs细胞核损伤降低,凋亡率下降,bcl-2的表达增加（P＜0.05）,bax和caspase-3表达降低（P＜0.05）。结论：TSG具有降低Hcy所致HUVECs的细胞损伤和抑制凋亡的作用,其机制可能与影响bcl-2、bax和caspase-3的表达有关。     

抗HER-2抗体chA21对人乳腺癌SKBR3细胞凋亡的诱导作用及其机制

目的探讨抗HER-2工程抗体chA21在体外对高表达HER-2的人乳腺癌SKBR3细胞凋亡的诱导作用及其分子机制。方法采用透射电镜和原位末端标记技术(TUNEL)观察和检测chA21对SKBR3细胞凋亡的诱导,采用免疫细胞化学技术检测凋亡相关基因bc l-2、bax、Fas及caspase-3表达的改变。结果chA21作用72 h,可见SKBR3细胞凋亡,chA21高浓度组(5.4mg/L)凋亡指数显著高于低浓度组(0.2 mg/L)(P<0.01);chA21处理组SKBR3细胞的bax、Fas及caspase-3表达增加,而bc l-2表达及bc l-2/bax比值降低,上述改变在chA21高、低两个浓度组间有显著差异(P<0.01)。结论chA21在体外可诱导SK-BR3细胞凋亡,其分子机制与调节凋亡相关基因bax、bc l-2、Fas及caspase-3的表达有关。     

miR-130a对大鼠脑基底动脉平滑肌细胞活力和凋亡的影响

目的:探讨微小RNA(miR)-130a对大鼠脑基底动脉平滑肌细胞(basilar arterial smooth muscle cells,BASMCs)生物学行为的影响及可能的作用机制。方法:采用real-time PCR法检测大鼠BASMCs在血管紧张素Ⅱ(AngⅡ)作用下miR-130a的表达水平。转染miR-130a inhibitor下调BASMCs中miR-130a的表达,采用CCK-8法和流式细胞术检测BASMCs活力、细胞周期及凋亡情况;Western blot检测细胞周期及凋亡相关调控因子细胞周期蛋白D1(cyclin D1)、细胞周期蛋白依赖性激酶2(CDK2)、p21、p-Rb、Bcl-2和cleaved caspase-3/caspase-3的蛋白水平。Real-time PCR及Western blot检测检测生长阻滞特异性同源盒蛋白(Gax)的表达情况。结果:AngⅡ可促进BASMCs中miR-130a的表达,而抑制Gax的表达。miR-130a inhibitor可部分抑制AngⅡ增加BASMCs细胞活力的效应,并上调Gax的表达。此外,下调miR-130a后细胞早期凋亡率显著增加(P0.05);同时细胞中cyclin D1、CDK2、Bcl-2和p-Rb的蛋白水平均显著降低,p21及cleaved caspase-3的蛋白水平显著升高(P0.05)。结论:沉默miR-130a可上调BASMCs中Gax的表达,进而影响细胞周期及凋亡相关因子的表达,从而抑制细胞活力,并促进其凋亡,提示miR-130a可作为高血压脑血管重构的一个潜在诊疗靶点。     

Effect of cobalt and chromium ions on bcl-2, bax, caspase-3, and caspase-8 expression in human U937 macrophages

The bcl-2 and caspase families of proteins play a central role in the modulation of apoptosis. The purpose of this study was to analyze the effect of Co(2+) and Cr(3+) ions on the expression of bcl-2, bax, caspase-3 and caspase-8 to better understand the mechanisms leading to ion-induced apoptosis in macrophages. U937 human macrophages were exposed to Co(2+) and Cr(3+) ions. The expression of proteins was measured by Western blot while caspase activities were measured by colorimetric assay. Results show that Co(2+) ions inhibited bcl-2 expression with significant effect (p<0.05) after 16 h and a maximal 52% inhibitory effect after 24 h. Co(2+) stimulated bax expression with a significant stimulation (p<0.05) after 8 h and a maximal 1.75-fold increase after 16 h. Co(2+) also stimulated the expression of the active fragment of caspase-3 as well as caspase-3 activity maximal increase after 24 h. Co(2+) ions had no effect on caspase-8 expression or activity.Cr(3+) ions inhibited bcl-2 expression with significant effect (p<0.05) after 16 h and a maximal 43% inhibitory effect after 24 h. Cr(3+) stimulated bax expression with significant stimulation (p<0.01) after 8h and a maximal 2.25-fold increase after 24 h. Cr(3+) ions also stimulated the expression of the active fragments of caspase-3 and -8, as well as the activities of both proteases. The effect of Cr(3+) ions on the expression of both caspase active fragments was maximal after 16 h incubation. In conclusion, our results suggest that the modulation of the expression of proteins from the bcl-2 and the caspase families of proteins are implicated in the induction of macrophage apoptosis by Co(2+) and Cr(3+) ions.