GOLPH3通过PI3K/Akt信号通路调控上皮性卵巢癌细胞增殖与凋亡的研究

目的:探讨GOLPH3基因对上皮性卵巢癌细胞增殖及凋亡的影响及作用机制。方法:siRNA干扰技术沉默SKOV3细胞株中GOLPH3基因表达,MTT法检测细胞增殖情况,流式细胞术检测细胞凋亡情况,Western blot法检测PI3K/Akt信号通路相关基因Akt、p-Akt 473、p-Akt 308及Bcl-2表达。PI3K/Akt信号通路抑制剂LY294002处理卵巢癌SKOV3细胞后,检测SKOV3细胞的增殖能力及凋亡情况。结果:siRNA干扰SKOV3细胞株中GOLPH3基因,GOLPH3表达下调,细胞增殖减少,凋亡增多;PI3K/Akt信号通路相关基因p-Akt 473、p-Akt 308、抗凋亡基因Bcl-2蛋白表达水平均下降,Akt蛋白水平表达无显著变化。LY294002处理SKOV3细胞后,细胞增殖率降低,凋亡率升高。结论:GOLPH3基因可能通过激活PI3K/Akt信号通路促进卵巢癌细胞增殖,并抑制其凋亡的作用。     

TFF3激活PI3K/Akt通路参与宫颈腺癌的发病机制

目的:探讨TFF3通过激活PI3K/Akt信号通路调控宫颈腺癌发生发展的机制。方法:TFF3细胞因子和PI3K/Akt信号通路抑制剂(LY294002)或两者共同处理Hela细胞,CCK-8法检测Hela细胞增殖能力,Transwell小室观察细胞迁移能力,流式细胞学方法检测细胞凋亡,Western blot检测PI3K/Akt信号通路关键蛋白Akt及其激活状态蛋白p-Akt的表达。结果:与对照组相比,TFF3处理后Hela细胞的增殖和迁移能力明显提高,细胞凋亡减弱,差异有统计学意义(P0.05);LY294002处理后Hela细胞的增殖及迁移能力明显降低,细胞凋亡增多,差异有统计学意义(P0.05);TFF3+LY294002处理后Hela细胞的增殖、迁移能力及细胞凋亡与TFF3和LY294002处理组比较,差异均有统计学意义(P0.05)。Western blot结果表明,TFF3能激活p-Akt基因表达。结论:TFF3能通过提高p-Akt蛋白表达激活PI3K/Akt信号通路,从而参与调节宫颈腺癌细胞的恶性行为。     

阻断PI3K/PKB通路对卵巢癌OVACA-3细胞株增殖和凋亡的影响

目的采用PI3K/PKB信号传导通路特异性抑制剂LY294002作用于人卵巢癌OVACA-3细胞,观察阻断PI3K/PKB信号传导通路对卵巢癌细胞增殖和凋亡等生物学特性的影响,揭示阻断PI3K/PKB信号传导通路治疗卵巢癌的机理和可行性。方法不同浓度的PI3K抑制剂LY294002作用于人卵巢癌OVACA-3细胞后,运用Western Blotting检测P-AKT及细胞核内NF-κBp65表达情况;MTT法、Annexin V-FITC流式细胞技术检测不同浓度的LY294002对卵巢癌OVACA-3细胞增殖及凋亡的影响。结果 LY294002可抑制人卵巢癌OVACA-3细胞中通路效应蛋白AKT、NF-κBp65的激活,且呈浓度及剂量依赖性。LY294002对细胞增殖抑制作用具有时间依赖性(F=10.398,P=0.001)和剂量依赖性(F=9.801,P=0.002)。LY294002可使卵巢癌细胞S期比例显著减少,G0/G1期比例增多,提示LY294002促使细胞在细胞周期G0-G1期受到阻滞。最终,抑制卵巢癌细胞增殖,促使其发生细胞凋亡,使细胞周期停滞在G1期。结论 PI3K/PKB信号传导通路阻断剂LY294002有可能成为治疗卵巢癌的新药,阻断PI3K/AKT信号传导通路可作为治疗卵巢癌的新切入点。     

VEGF和SDF-1/CXCR4在促进卵巢癌细胞侵袭与增殖中的相关作用

目的:研究血管内皮生长因子(VEGF)和趋化因子受体(Cys-X-Cysreceptor4,CXCR4)/配体基质细胞衍生因子-1(stromalcell-derivedfactor1,SDF-1)在卵巢上皮性癌细胞中的表达及其在促进卵巢癌细胞侵袭和增殖中的相关作用,进而探讨SDF-1/CX-CR4信号参与卵巢癌发生发展的相关机制。方法:(1)用Real-timeRT-PCR检测卵巢癌细胞株SKOV3中VEGF及其单克隆抗体anti-VEGF作用前后SDF-1/CXCR4mRNA表达水平的变化;(2)通过transwell小室体外侵袭实验检测VEGF和SDF-1以及anti-VEGF和CXCR4特异性抗体(AMD3100)对SKOV3细胞趋化活性的影响;(3)用MTT法测定VEGF和SDF-1以及anti-VEGF和AMD3100作用前后SKOV3细胞增殖率的变化。结果:(1)VEGF可以上调SDF-1和CXCR4的表达且有明显的剂量依赖性。(2)VEGF和SDF-1均有促进卵巢癌细胞侵袭的作用。VEGF的促侵袭作用具有一定的剂量依赖性且可以被40μg/mlanti-VEGF阻断,SDF-1的作用没有明显剂量依赖性;CXCR4的特异性受体抑制剂AMD3100有阻断VEGF和SDF-1的促侵袭作用。(3)VEGF和SDF-1均有促进卵巢癌细胞增殖的作用。VEGF的作用具有剂量依赖性,其效应可被anti-VEGF阻断,但不被AMD3100阻断,SDF-1的促增殖作用无明显剂量依赖性,其效应可被AMD3100阻断。结论:VEGF和SDF-1对卵巢癌细胞的侵袭和增殖有直接促进作用,并且VEGF可以上调SDF-1/CXCR4的表达。两者与卵巢癌的发生和生物学行为关系密切并协同促进卵巢癌细胞的转移。     

抑制PI3K/Akt信号通路拮抗胰岛素诱导的子宫内膜癌细胞增殖

目的:研究抑制磷脂酰肌醇3激酶(PI3K)/Akt信号通路对胰岛素诱导的子宫内膜癌细胞增殖的拮抗作用。方法:将无血清饥饿的子宫内膜癌Ishikawa3-H-12细胞分为空白对照组、10-6mol/L胰岛素单独刺激组以及不同剂量PI3K抑制剂-LY294002预处理后再用胰岛素刺激组。Western blot检测各组Akt磷酸化(p-Akt)水平,MTT试验观察细胞增殖情况。结果:胰岛素可引起内膜癌细胞Akt活化,刺激15min后p-Akt/Akt比值显著高于空白对照组(68.68%vs 26.21%,P<0.001)。LY294002以浓度依赖方式抑制胰岛素引起的Akt磷酸化。MTT试验显示,在药物处理24h,48h和72h 3个时间点,不同组别570nm吸光度值(OD570nm)均有显著差异(F=156.329,700.973,812.224,均P<0.001)。胰岛素组OD570nm值均高于同时间点的空白对照组(均P<0.001),胰岛素促内膜癌细胞增殖作用于48h时最为显著。LY294002可抑制胰岛素的增殖促进作用,此抑制作用具有浓度依赖性。不同剂量LY294002抑制作用的时间依赖性不同,48h时小剂量(0.1、1、10μmol/L)的抑制作用最为显著,72h时胰岛素重新呈现一定的促增殖作用;而50μmol/L LY294002可以持久抑制胰岛素的促增殖作用。结论:PI3K抑制剂LY294002可以通过抑制Akt磷酸化阻断胰岛素信号传导,拮抗后者促子宫内膜癌细胞增殖的作用。     

TFF3过表达促进宫颈腺癌Hela细胞增殖迁移侵袭功能及其机制研究

目的:探讨TFF3基因过表达对宫颈腺癌Hela细胞增殖、迁移、侵袭的影响及相关机制。方法:构建重组慢病毒(LV-TFF3)感染宫颈腺癌细胞系Hela,应用PI3K/Akt通路抑制剂LY294002及其溶剂DMSO分别处理TFF3过表达的Hela细胞。实时荧光定量PCR检测TFF3表达,CCK-8实验验证TFF3对Hela细胞增殖能力的影响,细胞划痕实验和Transwell实验检测TFF3对细胞迁移和侵袭功能的影响,Western blot法检测TFF3过表达对PI3K/Akt/Twist1信号通路及EMT相关蛋白表达的影响。结果:重组慢病毒(LV-TFF3)感染宫颈腺癌细胞系Hela后,TFF3基因表达水平明显增高(P0.01),细胞增殖、迁移、侵袭能力明显增强(P0.05),p-Akt、Twist1和Vimentin蛋白表达水平明显增高,E-Cadherin蛋白表达水平明显降低(P0.05)。TFF3过表达的Hela应用LY294002处理后细胞功能明显降低(P0.05),p-Akt、Twist1和Vimentin表达水平下降,E-Cadherin表达水平升高(P0.05)。结论:TFF3过表达可能通过激活PI3K/Akt/Twist1信号转导通路,增强宫颈腺癌Hela细胞的增殖、迁移及侵袭能力,并引发EMT,促进宫颈腺癌的恶性生物学行为。     

信号传导通路抑制剂PD98059和LY294002对子宫内膜癌细胞和裸鼠移植瘤的抑制作用

目的 观察有丝分裂原活化蛋白激酶(MAPK)信号传导通路抑制剂PD98059和磷脂酰肌醇3激酶(PI3K)信号传导通路抑制剂LY294002对子宫内膜癌细胞株Ishikawa细胞和子宫内膜癌裸鼠移植瘤的抑制作用.方法 (1)体外实验:实验分为4组,即PD组(加入浓度分别为0、1、50、100 μmol/L的PD98059)、LY组(加入浓度分别为0、1、50、100 μmol/L的LY294002)、PD+LY组(加入浓度均为50 μmol/L的PD98059和LY294002)、对照组[仅加入二甲基亚砜(DMSO)],分别培养24、48和72 h.应用四甲基偶氮唑蓝(MTT)比色法检测各组Ishikawa细胞的增殖情况,流式细胞仪检测各组Ishikawa细胞的细胞周期比例和细胞凋亡率.(2)体内实验:建立子宫内膜癌裸鼠移植瘤模型,随机分为4组(每组6只):PD组(注射PD98059 50 mg/kg)、LY组(注射LY294002 50 mg/kg)、PD+LY组(注射PD98059 50 mg/kg和LY294002 50 mg/kg)、对照组(注射等量的生理盐水),每周2次,共3周;观察移植瘤的生长情况,并计算抑瘤率;用末端脱氧核苷酸转移酶介导的脱氧尿苷三磷酸标记(TUNEL)法检测移植瘤组织的细胞凋亡情况,以细胞凋亡指数表示;免疫组化法检测移植瘤组织内磷酸化细胞外信号调节激酶(p-ERK)和磷酸化蛋白激酶B(p-Akt)蛋白的表达.结果 (1)PD98059和(或)LY294002处理后,PD组、LY组Ishikawa细胞增殖的抑制作用均呈明显的时间和浓度依赖性(P＜0.05),且PD+LY组细胞增殖的这种抑制作用明显高于PD组、LY组(P＜0.05).LY组细胞S期、G0/G1期比例的变化呈明显的时间和浓度依赖性(P＜0.05);PD组细胞各期比例的变化均无时间依赖性(P＞0.05),但G0/G1期、S期比例的变化呈明显的浓度依赖性(P＜0.05);PD+LY组与PD组、LY组比较,G0/G1期比例明显增加、S期比例明显减少(P＜0.05).PD+LY组细胞凋亡率为(63.3±0.5)%,明显高于PD组、LY组[分别为(30.7±20.1)%和(40.8±1.3)%,P＜0.01].(2)注射PD98059和(或)LY294002后,随着时间的延长,PD组、LY组、PD+LY组裸鼠移植瘤体积增长相对缓慢,对照组移植瘤体积增长明显,PD组、LY组、PD+LY组分别与对照组比较,差异均有统计学意义(P＜0.05);PD+LY组分别与PD组、LY组比较,差异也均有统计学意义(P＜0.05),而PD组与LY组比较,差异无统计学意义(P＞0.05).LY组、PD组、PD+LY组抑瘤率分别为(32±16)%、(38±17)%、(68±9)%,PD+LY组明显高于LY组、PD组(P＜0.05).LY组、PD组、PD+LY组细胞凋亡指数分别为(13.7±1.5)%、(14.1±1.2)%、(29.0±1.8)%,PD+LY组明显高于LY组、PD组(P＜0.01).LY组、PD组、LY+PD组裸鼠移植瘤组织中p-ERK和p-Akt蛋白的表达强度均明显弱于对照组.结论 信号传导通路抑制剂PD98059、LY294002能够抑制体外及体内子宫内膜癌细胞的生长,并促进其凋亡.

Abstract：

Objective To investigate the effects of signal pathway inhibitors PD98059 and LY294002 on cell proliferation, apoptosis, expressions of phosphorylated extracellular signal-regulared kinase (p-ERK) and phosphorylated protein kinase B ( p-Akt) in endometrial carcinoma xenografts. Methods Human endometrial carcinoma Ishikawa cells were cultured in vitro. The effects of PD98059 and LY294002 on proliferation, apoptosis, and cell cycle distribution of endometrial cancer cells were detected by monotetrazolium ( MTT) assay and fluorescence-activated cell sorting technique. The models of xenografted tumor were established by the subcutaneous inoculation in 24 nude mice, and then they were randomly divided into 4 groups ( n = 6) , normal saline group, PD98059 group (PD group) , LY294002 group ( LY group) or PD98059 + LY294002 group ( PD + LY group) by intraperitoneal injections, respectively. The anti-tumor efficacy was evaluated by measuring tumor volume and tumor growth status. The histopathological change of tumor specimens was observed using HE staining and terminal deoxynucleotidyl transferasemediated dUTP-digoxigen in nick and labeling method (TUNEL) testing and the expression levels of p-ERK and p-Akt were detected by immunohistochemistry method. Results ( 1) The proliferation of Ishikawa cells were suppressed after treated by PD98059 and ( or) Y294002, in which A570 values of cells decreased showing both time-dependent and concentration-dependent manner ( LY294002: Fgroup = 9. 801, P = 0. 002; Ftime = 10. 398, P = 0. 001. PD98059: Fgroup= 8. 213, P = 0. 015; Ftime = 6. 839, P = 0. 036). Cell cycle distribution analysis revealed that percentage of Ishikawa cells at G0/G1 phase(Ftime =35.049, P= 0.004; Fgroup = 32. 024, P ＜0. 01) increased and percentage of S phase cells (Ftime = 7. 789, P = 0. 049; Fgroup = 30. 132, P ＜0. 01) decreased significantly. The percentage of apoptotic cells increased significantly among PD group, LY group and PD + LY group, in which there were significant difference [(63. 3 ±0.5)% vs (30. 7 ± 20. 1) % vs(40. 8 ± 1. 3) % ; F = 621. 059, P ＜ 0. 01]. (2) Compared with the control group, the increasing of transplanting tumor volume in the treated groups were obviously ( F = 23. 545 , P ＜ 0. 01) , and the inhibited rate of the tumor was higher in PD + LY group than that in PD group or LY group [(68 ± 9 ) % vs ( 32 ± 16 ) % or ( 38 ± 17 ) % ; F = 10. 283 , P ＜ 0. 05]. ( 3 ) HE staining shown that there were different degrees of necrosis for endometrial carcinoma cell in different groups. The apoptosis of tumor cells were significantly increased in treated groups by TUNEL testing [(13. 7 ± 1. 5)% , ( 14. 1 ± 1. 2)% , (29. 0 ± 1. 8 ) % ; F = 320. 344, P ＜ 0. 01]. Immunohistochemistry results demonstrated that the expressions of p-ERK and p-Akt in treated groups were lower than that in control group, of which LY + PD group was the lowest one. Conclusion The signal pathway inhibitors PD98059 and LY294002 could inhibit the growth of human endometrial carcinoma in vivo and in vitro, in which may induce cell apoptosis.     

细胞外信号调节激酶信号通路对蛋白酶体抑制剂MG262诱导卵巢上皮性癌细胞凋亡的调控作用

目的 探讨细胞外信号调节激酶(ERK)信号通路对蛋白酶体抑制剂MG262诱导卵巢上皮性癌(卵巢癌)细胞凋亡的调控作用.方法 不同浓度(1、10、20、40、60、80 nmol/L)的MG262分别处理卵巢癌细胞株SKOV3细胞24、48 h后,四甲基偶氮唑蓝(MTT)比色法检测SKOV3细胞的存活率.MG262及ERK抑制剂PD98059分别及联合处理24 h后,流式细胞仪检测SKOV3细胞及胚肾上皮细胞株293T细胞的凋亡率;酶联免疫吸附试验(ELISA)及蛋白印迹法分别检测SKOV3细胞培养上清液中血管内皮生长因子(VEGF)的浓度及细胞内VEGF蛋白的表达.MG262处理不同时间(3、6,9、12 h)后,蛋白印迹法检测SKOV3细胞内磷酸化ERK(p-ERK)及野生型p53蛋白的表达.以上实验以未加药物者为对照.结果 MTT比色法检测发现,随着MG262浓度的增加,SKOV3细胞的存活率明显下降(P＜0.05).流式细胞仪检测发现,MG262、PD98059分别或联合处理SKOV3细胞后,其细胞凋亡率分别为(30.7±4.3)%、(26.8±8.6)%、(50.3±10.6)%,与对照细胞的(7.9±1.9)%比较,差异均有统计学意义(P＜0.05);两药单独处理者分别与联合处理者比较,差异也均有统计学意义(P＜0.01).而两药分别或联合处理293T细胞后,其细胞凋亡率分别为(14.5±5.3)%、(16.2±7.5)%、(10.8±7.3)%,与对照细胞的(12.2±6.3)%比较,差异均无统计学意义(P＞0.05).ELISA及蛋白印迹法检测显示,MG262处理后SKOV3细胞培养上清液中VEGF的浓度及细胞内VEGF蛋白的表达水平均明显下降(P＜0.05).MG262处理不同时间后,SKOV3细胞内p-ERK蛋白的表达水平明显下降(P＜0.05);但SKOV3细胞内野生型p53蛋白在MG262处理前、后均无表达.结论 MG262可通过ERK信号通路诱导卵巢癌细胞凋亡,抑制卵巢癌细胞的增殖及血管生成.     

VEGF-C对宫颈癌细胞增殖和凋亡信号传导通路的影响

目的:研究VEGF-C对体外培养的宫颈癌HeLa细胞增殖和凋亡的影响;研究VEGF-C受体KDR、信号通路PI3K、MAPK在VEGF-C对宫颈癌增殖和凋亡调控中的作用。方法:应用重组人VEGF-C蛋白体外刺激宫颈癌HeLa细胞,MTT法检测细胞增殖,流式细胞仪检测细胞周期和凋亡,Western blot检测增殖与凋亡相关基因Bcl-2、CyclinD1蛋白表达;应用KDR-Ab、信号通路PI3K抑制剂LY294002、信号通路MAPK抑制剂PD98059预处理HeLa细胞,再进行VEGF-C刺激,观察上述指标的变化。结果:重组VEGF-C(50ng/μl)刺激HeLa细胞后增殖指数增加(2.13 vs 1),细胞周期S期比率增多[(64.26±0.20)%vs(30.91±0.09)%,P<0.05],细胞凋亡率降低(3.29±0.35 vs 7.44±0.55,P<0.05);Bcl-2、Cyclin D1表达增加(P<0.05)。KDR-Ab、LY294002预处理后与VEGF-C组相比增殖指数降低,细胞周期S期比率下降,凋亡指数升高,Bcl-2、Cyclin D1表达降低。PD98059预处理后,与VEGF-C组相比增殖指数降低、细胞周期S期比率下降、Bcl-2、Cyclin D1表达降低,但对VEGF-C诱导的凋亡无明显影响。结论:外源性VEGF-C作用于肿瘤细胞自身的KDR受体,激活细胞内信号传导通路MAPK途径和(或)PI3K途径诱导Cyclin D1表达,使肿瘤细胞S期加快,促进细胞周期的进程,进而促进He-La细胞增殖;通过PI3K途径诱导Bcl-2表达,抑制凋亡。     

SDF-1/CXCR4对卵巢上皮性癌细胞增殖和侵袭的影响

目的:研究SDF-1/CXCR4在卵巢癌细胞生物学活性中的作用。方法:用RT-PCR方法检测卵巢癌细胞株SW626及Anglne中的SDF-1和CXCR4的表达。细胞经外源性SDF-1或者抗CXCR4单克隆抗体干预后,用MTT法检测细胞增殖,PI测细胞凋亡,Annexin-V/PI法检测细胞早期凋亡,Transwell小室检测细胞的迁移侵袭活性。结果:两株卵巢癌细胞株中,SW626细胞既表达SDF-1又表达CXCR4,Anglne细胞则两者均不表达。在SW626细胞中,SDF-1作用于无血清状态下培养的细胞(吸光度A值为0.911±0.01),与对照组(吸光度A值为0.506±0.01)相比,差异有统计学意义(P<0.01),而加入抗CXCR4单克隆抗体作用后(10μg/ml A值为0.725±0.01,20μg/ml A值为0.650±0.02),与SDF-1组相比,差异均有统计学意义(分别为P<0.05和P<0.01);抗CXCR4单克隆抗体作用于无血清状态下培养的细胞(10μg/ml A值为0.655±0.11和20μg/ml A值为0.520±0.04),与对照组(A值为0.724±0.03)相比,差异均有统计学意义(P<0.05)。加入外源性SDF-1后,SW626细胞在无血清状态下的早期凋亡数为15.6%,相对于对照组,差异有统计学意义(P<0.01)。抗CXCR4单克隆抗体可增加SW626细胞中的PI阳性细胞数(P<0.01)。并且,与对照组相比,SDF-1促进SW626细胞的迁移和侵袭能力增强(P<0.01),而此活性可被抗CXCR4单克隆抗体阻断。结论:SDF-1/CXCR4可能通过促进细胞增殖、迁移、侵袭及抑制其凋亡,使卵巢癌细胞获得进展。     

Stromal cell-derived factor 1alpha stimulates human endometrial carcinoma cell growth through the activation of both extracellular signal-regulated kinase 1/2 and Akt

OBJECTIVE: The aim of study was to investigate the proliferative effects of stromal cell-derived factor-1alpha (SDF-1alpha) on endometrial carcinomas cell lines with different estrogen receptors (ER) and PTEN protein profiles. METHODS: MTT assays was used to detect the proliferation of HEC-1A and Ishikawa cells, and Western blotted analysis was used to detect activation of Akt and ERK1/2 in both cell lines after exposure to various concentrations of SDF-1alpha, MAPK-specific inhibitor PD98059 or PI3K-specific inhibitor LY294002. RESULTS: Low concentrations of SDF-1alpha (50 ng/ml) induced proliferation in both cell lines. ERK1/2 was significantly activated for more than 2 h by SDF-1alpha at 20 ng/ml in HEC-1A cells, but not in Ishikawa cells. In contrast, Akt was significantly activated for over 2 h in Ishikawa cells but remained unchanged in HEC-1A cells. High concentrations of SDF-1alpha activated Akt and ERK1/2 pathways in both cell lines in a dose-dependent manner, which was primarily inhibited by LY294002 for pAkt and by PD98059 for pERK 1/2. CONCLUSIONS: SDF-1alpha could stimulate the cell proliferation of endometrial carcinoma with different expression status of ER and PTEN in vitro, likely through the activation of both Akt and ERK1/2 signaling pathways.     

阻断丝裂原活化蛋白激酶信号通路对子宫内膜癌生长抑制作用的研究

目的:研究丝裂原活化蛋白激酶(MAPK/ERK)信号通路抑制剂(PD98059)对ER阳性表达的Ishikawa和ER低表达的HEC-1A人子宫内膜癌细胞系的裸鼠体内抗增殖作用,探讨阻断MAPK/ERK信号传导通路治疗子宫内膜癌的可行性。方法:体外培养人子宫内膜癌Ishikawa、HEC-1A细胞,将对数生长期的两种细胞分别接种于裸鼠背部皮下,建立子宫内膜癌裸鼠移植瘤模型。将两种细胞系成瘤阳性裸鼠随机分为对照组和实验组,每组6只,分别腹腔注射生理盐水和PD98059,每周2次,共3周,观察各组裸鼠移植瘤的生长情况,建立移植瘤生长曲线,计算抑瘤率。实验结束时取肿瘤组织切片HE染色,原位末端标记(TUNEL)法检测组织细胞的凋亡,Western blot检测各组织中ERK1/2的活化。结果:(1)PD98059能有效抑制人子宫内膜癌Ishikawa、HEC-1A细胞裸鼠皮下移植瘤的生长;(2)HE染色可见实验组瘤细胞核浆比相对较小,血管密度降低;TUNEL染色可见两种细胞移植瘤中实验组细胞凋亡率较对照组明显增加;(3)Western blot检测结果:PD98059能有效降低裸鼠移植瘤组织中p-ERK表达。结论:PD98059通过阻断MAPK/ERK信号传导通路增加Ishikawa和HEC-1A细胞裸鼠移植瘤组织中细胞凋亡,抑制肿瘤生长,抗肿瘤效果明显,可成为治疗子宫内膜癌的有效方法。     

Phosphatidylinositol 3-kinase/Akt regulates the balance between plasminogen activator inhibitor-1 and urokinase to promote migration of SKOV-3 ovarian cancer cells

OBJECTIVES: Increased levels of urokinase-type plasminogen activator (uPA) are associated with shortened overall survival in ovarian cancer patients. Additionally, elevated levels of the serine protease inhibitor (serpin), plasminogen activator inhibitor-1 (PAI-1), a uPA inhibitor, have also been correlated with an unfavorable prognosis in ovarian cancer. Therefore, it is critical to understand the signaling pathways that regulate PAI-1 and uPA expression in cancer cell migration-invasion. METHODS: We studied the PI3K/Akt, Rho kinase/ROCK, p38 MAPK and MEK pathways and their modulation of PAI-1 and uPA expression and wound-induced cell migration in SKOV-3 ovarian cancer cells. The PI3K/Akt pathway was further examined using pharmacological inhibitors (LY294002 and wortmannin), Akt siRNA, constitutively active Akt adenovirus and treatment with IGF-1/insulin in the SKOV-3 cells. RESULTS: The PI3K/Akt pathway negatively regulates PAI-1 expression and positively correlates with migratory abilities and uPA expression in SKOV-3 cells. A reduction in active Akt results in an increase in PAI-1 expression coupled with a decrease in uPA expression to ultimately result in reduced cell migration and invasion. By contrast, an increase in Akt activity reduces PAI-1 expression and results in an increase in SKOV-3 wound-induced cell migration. Furthermore, IGF-1 and insulin stimulated SKOV-3 migration by altering the balance between uPA and PAI-1 to favor uPA, and the enhanced migration was attenuated by treatment with LY294002 indicating PI3K/Akt in this pathway. CONCLUSIONS: These results suggest an overall ovarian tumor-protective role for PAI-1, and that the PI3K/Akt signaling pathway regulates the ratio of PAI-1:uPA to either increase or decrease cell migration.     

多囊卵巢综合征患者子宫内膜组织中胰岛素PI3K/Akt信号通路的活化及其意义

目的 通过分析多囊卵巢综合征(PCOS)患者子宫内膜组织中胰岛素的磷脂酰肌醇3激酶(PI3K)/蛋白激酶B(Akt)信号通路中Akt的表达及其活化程度,探讨PI3K/Akt信号通路活化在PCOS子宫内膜增生及癌变形成中的作用及意义,并分析影响该信号通路活化程度的因素.方法 选择2007年1月-2008年6月在天津医科大学总医院就诊的PCOS患者52例为PCOS组,非PCOS(输卵管因素不孕或卵巢良性肿瘤)患者32例为对照组;测定所有患者的血清生殖激素水平、空腹血糖及胰岛素水平,并取子宫内膜组织行病理检查;计算体质指数(BMI)、稳态模型评估法计算的胰岛素抵抗指数(HOMA-IR).对PCOS组患者根据病理检查结果分为正常子宫内膜、子宫内膜增生及癌变,根据是否存在胰岛素抵抗分为胰岛素抵抗和非胰岛素抵抗.蛋白印迹法检测子宫内膜组织中Akt、磷酸化Akt(p-Akt)蛋白的表达水平.结果(1)PCOS组患者子宫内膜组织中p-Akt蛋白的表达水平[(46±18)％]高于对照组[(33±9)％],两组比较,差异有统计学意义(P＜0.01).(2)PCOS组子宫内膜增生及癌变患者子宫内膜组织中p-Akt蛋白的表达水平[(56±19)％]高于正常子宫内膜者[(31±12)％],两者比较,差异有统计学意义(P＜0.05);胰岛素抵抗患者子宫内膜组织中p-Akt蛋白的表达水平[(50±19)％]高于非胰岛素抵抗者[(34±10)％],两者比较,差异有统计学意义(P＜0.01).(3)HOMA-IR、BMI与子宫内膜组织中p-Akt蛋白的表达水平呈正相关(r=0.400、0.326,P均＜0.05).结论 PCOS患者子宫内膜存在胰岛素PI3K/Akt信号通路的过度活化,该信号通路过度活化与PCOS子宫内膜增生及癌变有关.胰岛素抵抗、肥胖可能是影响子宫内膜组织中胰岛素PI3K/Akt信号通路过度活化的独立风险因素.     

瘦素(leptin)对卵泡生长的启动作用及机制研究

目的:探讨瘦素(leptin)在原始卵泡启动生长中的作用及其机制。方法:利用2日龄大鼠离体卵巢体外培养模型,在Waymouth培养体系中分别添加瘦素、瘦素抑制剂(leptin antagonist)以及ERK1/2信号通路特异性抑制剂(PD98059),通过形态学观察原始卵泡启动生长的变化,Westernblotting检测卵泡ERK1/2、磷酸化-ERK1/2(P-ERK1/2)蛋白表达量的变化。结果:瘦素能够促进原始卵泡的启动生长(P<0.05),还可激活卵泡ERK1/2信号通路中的ERK1/2蛋白磷酸化(P<0.05);用瘦素抑制剂和PD98059可显著抑制瘦素促原始卵泡生长效应(P<0.05),亦可显著抑制瘦素对卵泡ERK1/2蛋白磷酸化(P<0.05)。结论:瘦素能够促进原始卵泡的启动生长,其作用机制可能与ERK1/2信号通路有关。     

Hypoxia Enhances FGF2- and VEGF-Stimulated Human Placental Artery Endothelial Cell Proliferation: Roles of MEK1/2/ERK1/2 and PI3K/AKT1 Pathways

Placental development occurs under a low oxygen (2–8% O₂) environment, which is critical for placental development and angiogenesis. In this study, we examined if hypoxia affected fibroblast growth factor-2 (FGF2)- and vascular endothelial growth factor (VEGF)-stimulated cell proliferation via the mitogen-activated protein kinase kinase 1/2 (MEK1/2)/extracellular signal-regulated kinases 1/2 (ERK1/2) and phosphatidylinositol-3 kinase (PI3K)/v-akt murine thymomaviral oncogene homologue (AKT1) pathways in human placental artery endothelial (HPAE) cells. We observed that under normoxia (～20% O₂), FGF2 and VEGF dose-dependently stimulated cell proliferation. Hypoxia (3% O₂) significantly promoted FGF2- and VEGF-stimulated cell proliferation as compared to normoxia. Under both normoxia and hypoxia, FGF2 rapidly induced ERK1/2 and AKT1 phosphorylation, while VEGF-induced ERK1/2, but not AKT1 phosphorylation. However, hypoxia did not significantly alter FGF2- and VEGF-induced ERK1/2 and AKT1 phosphorylation as compared to normoxia. PD98059 (a MEK1/2 inhibitor) at 20 μM and LY294002 (a PI3K inhibitor) at 5 μM attenuated FGF2- and VEGF-induced phosphorylation of ERK1/2 and AKT1, respectively. PD98059, even at doses that drastically inhibited FGF2-induced ERK1/2 phosphorylation (20 μM) and caused cell loss (40 μM), did not affect FGF2-stimulated cell proliferation, which was confirmed by U0126 (another potent MEK1/2 inhibitor). PD98059, however, dose-dependently inhibited VEGF-stimulated cell proliferation. Conversely, LY294002 dose-dependently inhibited FGF2-, but not VEGF-stimulated cell proliferation. These data suggest that in the MEK1/2/ERK1/2 and PI3K/AKT1 pathways differentially mediate FGF2- and VEGF-stimulated HPAE cell proliferation. These results also indicate that hypoxia promotes FGF2- and VEGF-stimulated cell proliferation without further activation of the PI3K/AKT1 and MEK1/2/ERK1/2, respectively.     

雷公藤内酯醇联合紫杉醇对COC1/DDP细胞凋亡的影响及其对PI3K/AKT/GSK3β信号通路的调控

目的：通过研究雷公藤内酯醇（TP）联合紫杉醇对耐顺铂人上皮性卵巢癌细胞（COC1/DDP细胞）凋亡的影响,以探讨两药联合对COC1/DDP细胞作用的机制。方法：将对数生长期COC1/DDP细胞随机分为6组：空白对照组、紫杉醇组（3.13μg/ml）、LY294002组（10μmol/ml）、TP组（10ng/ml）、LY294002＋紫杉醇组（10μmol/ml LY294002＋3.13μg/ml紫杉醇）、TP＋紫杉醇组（10ng/ml TP＋3.13μg/ml紫杉醇）。采用MTT法检测各组的细胞增殖活性;普通光镜及AO/EB染色荧光显微镜观察细胞形态的变化;Annexin V-FITC/PI双染法流式细胞仪检测细胞凋亡率;Western blot法检测各组细胞中Akt、pAkt、GSK3β、p-GSK3β蛋白的表达变化。结果：（1）细胞增殖抑制率：TP＋紫杉醇组显著高于TP、紫杉醇组（P〈0.05）;LY294002＋紫杉醇组显著高于LY294002、紫杉醇组（P〈0.05）。联合用药组中,TP＋紫杉醇组显著高于LY294002＋紫杉醇组（P〈0.05）;单用药组中,TP组〉紫杉醇组〉LY294002组（P〈0.05）。各组抑制率均呈时间依赖性（P〈0.05）。（2）普通光镜及AO/EB染色荧光显微镜下观察,除空白组外,各用药组的细胞形态均有凋亡样改变。两联合用药组的细胞凋亡数显著高于各自单药组,TP＋紫杉醇组高于LY294002＋紫杉醇组;单用药组的细胞凋亡数：TP组〉紫杉醇组〉LY294002组。（3）流式细胞仪检测发现,两联合用药组的细胞凋亡率大于各自单药组（P〈0.05）。联合用药组中,TP＋紫杉醇组凋亡率显著高于LY294002＋紫杉醇组（P〈0.05）;单药组的细胞凋亡率为：TP〉紫杉醇〉LY294002（P〈0.05）。（4）p-Akt蛋白和p-GSK3β蛋白的表达从空白对照组→紫杉醇组→LY294002组→TP组→LY294002＋紫杉醇组→TP＋紫杉醇组,呈逐渐减少的趋势,而总Akt、GSK3β蛋白的表达不变。结论：TP可协同紫杉醇促进COC1/DDP细胞凋亡,其机制可能是通过抑制PI3K/Akt/GSK3β信号通路,从而下调了耐药相关蛋白p-Akt、p-GSK3β的表达。     

E-钙粘素介导的细胞粘附通过EGFR激活卵巢癌细胞PI3K-Akt信号通路

目的研究E-钙粘素介导的细胞粘附对卵巢癌细胞Akt及其上游的磷脂酰肌醇3-激酶(phosphatidylinositol 3-Kinase,PI3K)信号的激活及对卵巢癌细胞增殖的作用。方法基于卵巢癌细胞株CaOV-3构建Ca2+依赖性细胞粘附模型;Western blot和免疫沉淀法检测E-钙粘素介导的细胞粘附通过表皮生长因子受体(epidermal growth factor recep-tor,EGFR)对PI3K-Akt的激活;同时通过阻断该通路的关键组分观察对卵巢癌细胞增殖的影响。结果(1)E-钙粘素介导的细胞粘附可激活卵巢癌细胞内部的EGFR-PI3K-Akt信号通路;(2)应用E-钙粘素抗体或PI3K抑制剂处理的CaOV-3细胞株表现出生长受阻的现象,72h时细胞生长抑制率分别达73.5%和78.8%。结论E-钙粘素激活卵巢癌细胞EGFR-PI3K-Akt相关的信号转导通路对肿瘤细胞的增殖有重要作用。干预该信号通路的关键组分显著抑制细胞生长,为卵巢癌的靶向治疗提供了新的有价值的干预靶点。