AKT反馈激活拮抗4EGI-1对黑素瘤A375细胞的抑制作用

目的：探索4EGI-1对黑素瘤A375细胞中AKT通路的激活作用及后者对4EGI-1抑制A375细胞增殖的影响。方法： 用20、40、60 μmol/L的4EGI-1处理黑素瘤A375细胞12、24 h,Western boltting检测4EGI-1对A375细胞中AKT磷酸化的影响;A375细胞分别受4EGI-1（40 μmol/L）、BEZ235（5 μmol/L）、4EGI-1（40 μmol/L）+BEZ235（5 μmol/L）联合处理, CCK-8实验和流式细胞术分别检测4EGI-1、BEZ235单独或联合处理对A375细胞增殖和细胞周期的影响,Western boltting检测对细胞周期相关蛋白CyclinD1表达的影响。结果： 4EGI-1促进A375细胞中AKT的磷酸化,且具有剂量依赖性;而BEZ235能够拮抗4EGI-1对AKT的促磷酸化作用。与4EGI-1组和BEZ235组相比,联合组的A375细胞增殖抑制率显著升高\[24 h时,4EGI-1组和BEZ235组抑制率分别为（7.6±1.2）%和（2.4±3.1）%,而联合组抑制率为（19.8±4.3）%;P<0.05\],S期细胞比例显著降低（4EGI-1组和BEZ235组S期细胞比例分别为25.65%和25.82%,联合处理组细胞S期为13.08%;P<0.05）,CyclinD1表达显著降低（4EGI-1组和BEZ235组CyclinD1相对表达值为0.81±0.04和0.76±0.04,联合处理组细胞CyclinD1相对表达值为0.25±0.03;P<0.05）。结论：AKT反馈激活拮抗4EGI-1对黑素瘤A375细胞的抑制作用,联合使用AKT抑制药物能够增强4EGI-1对A375细胞的生长抑制作用。     

对羟基桂皮醛诱导食管癌TE-13细胞分化及其作用机制

目的：探讨木鳖子单体化合物对羟基桂皮醛（p-hydroxylcinnamaldehyde,CMSP）对食管癌细胞株TE-13的分化作用及其机制。方法：用流式细胞术检测质量浓度为10、20、40 μg/ml的 CMSP处理TE-13细胞对该细胞凋亡和细胞周期分布的影响,用吉姆萨染色、电镜观察TE-13细胞形态学改变,Real-time PCR和ELISA方法检测TE-13细胞中肿瘤相关抗原CEA和SCC的表达,用克隆集落形成实验、Transwell迁移实验检测不同质量浓度CMSP对TE-13细胞的增殖、迁移能力的影响,Western blotting检测CMSP（20 μg/ml）对TE-13细胞中MAPK通路中各蛋白水平的影响。结果： CMSP可抑制食管癌Kyse30、TE-13、Eca109和Kyse180细胞的增殖\[(1.6±0.2)×104 vs （3.8±0.3)×104、(1.7±0.3)×104 vs (4.5±0.4)×104、 (2.5±0.1)×104 vs (4.0±0.4)×104、(1.5±0.1)×104 vs (2.5±0.3)×104个细胞, 均P<0.01\],而对人食管上皮细胞无明显作用(P>005)。CMSP处理TE-13细胞后：(1) 随CMSP质量浓度（10 、20 、40 μg/ml）和处理时间的增加（24、48、72 h）,G0/G1期细胞数量均增加、S期细胞数量减少（P<0.01或 P<0.05）,但细胞凋亡率无明显变化（P>0.05）;(2) 细胞出现典型分枝状突起,且随CMSP质量浓度增加更显著（P<0.05）;（3）CEA和SCC水平显著降低（P<0.01）;（4）抑制TE-13细胞的增殖和迁移能力,诱导细胞分化;（5）p-P38蛋白水平明显升高（P<0.01）,而p-ERK、p-SPKA/JNK蛋白水平明显降低（P<0.01）。结论： CMSP抑制食管癌TE-13细胞的增殖、诱导其分化,其作用机制可能与上调MAPK信号通路中p-P38和下调p-ERK、p-SPKA/JNK有关。     

TLR1/2信号促CD8+T细胞功能及其机制

目的：探讨Toll 受体1/2(Toll like receptor 1/2, TLR1/2)信号对荷瘤小鼠来源的CD8+T细胞功能的影响及其可能机制。方法：利用小鼠Lewis肺癌细胞株3LL建立小鼠肺癌荷瘤模型,MACS分选小鼠脾CD8+T细胞;体外经PBS或TLR1/2激动剂BLP刺激后,Real-time PCR和流式细胞术分别从基因和蛋白水平检测CD8+T细胞的TLR分子表达;用ELISA和流式细胞术检测经PBS或BLP刺激后的CD8+T细胞分泌细胞因子和增殖的能力,并用关键信号分子抑制剂分析可能的分子机制。结果：与PBS对照组相比,TLR1/2激动剂BLP不但有效上调荷瘤机体CD8+T细胞TLR1和TLR2分子的基因水平\[TLR1：（0.353±0.015） vs （0101±0.017）,P<0.01;TLR2：（0.232±0.031） vs （0.080±0.004）,P<0.05\]及蛋白水平（P<0.05）,而且显著促进CD8+T细胞分泌功能性细胞因子\[IFN-γ：（2 375±305） vs （850±50）,P<0.05;IL-2：（1 600±200） vs （350±50）,P<0.05\]和增殖的能力（P<0.05）,这一效应依赖于NF-κB和P38通路。结论： TLR1/2信号直接作用于荷瘤小鼠的CD8+T细胞并促进其功能,该研究既丰富了TLR的作用范围,也为基于TLR激动剂的肿瘤生物治疗提供了实验依据。     

桥接整合因子1 去甲基化诱导细胞周期阻滞抑制食管鳞状细胞癌EC109细胞增殖

目的：分析桥接整合因子1（bridging integrator-1, Bin1）去甲基化对Bin1 基因表达和食管鳞状细胞癌EC109 细胞增殖能力的影响,并初步探讨其可能的作用机制。方法：甲基化特异性PCR（methylation specific polymerase chain reaction, MSP）法检测去甲基化药物5-氮杂-2''脱氧胞苷（5-Aza-2''-deoxycytidine, 5-Aza-dc）处理后EC109 细胞Bin1 启动子区域的甲基化状态,用qPCR、Western blotting 和MTT法分别检测单独5-Aza-dc 和5-Aza-dc 加转染Bin1 基因干扰片段（Bin1 siRNA）处理对EC109 细胞Bin1 mRNA及其蛋白表达和细胞增殖能力的影响,流式细胞术和Western blotting 检测5-Aza-dc 处理后EC109 细胞周期和细胞周期相关蛋白（Cyclin D1 与CDK4）表达的变化。结果：去甲基化药物5-Aza-dc 处理后,EC109 细胞Bin1 基因启动子区域发生去甲基化。5-Aza-dc 处理的Bin1 去甲基化EC109 细胞Bin1 mRNA和蛋白表达明显上调（均P<0.05）,细胞增殖能力明显下降（P<0.05）,细胞阻滞在G0/G1 期,表现为S 期细胞比例显著减少,细胞周期相关蛋白Cyclin D、CDK4 表达均明显下调（均P<0.05）。Bin1 去甲基化EC109 细胞转染Bin1 siRNA后,Bin1 mRNA和蛋白表达明显下调,细胞增殖能力增强（均P<0.05）。结论：Bin1 基因启动子区域在EC109 细胞中呈完全甲基化状态,5-Aza-dc 去甲基化可使食管鳞癌细胞EC109 细胞Bin1 表达升高,通过降低细胞周期相关蛋白表达诱导细胞周期阻滞抑制EC109 细胞增殖。证实表观遗传学变化可能与食管癌细胞恶性增殖有关,可为食管癌治疗提供新的思路。     

RNA干扰下调Slug表达对肺癌细胞A549的细胞周期、增殖和侵袭的影响

目的：应用RNA干扰技术下调肺癌A549细胞中Slug基因的表达,探讨其对A549细胞增殖、细胞周期和细胞侵袭能力的影响。方法：构建靶向Slug基因的shRNA真核表达质粒pGPU6-GFP-Neo-Slug,与阴性对照质粒pNeg-shRNA分别用脂质体法转染A549细胞。Real-time PCR和Western blotting验证转染后Slug mRNA和蛋白的表达。CCK-8法、流式细胞术和Transwell实验分别检测下调Slug表达对A549细胞增殖、细胞周期和侵袭能力的影响。结果：成功构建pGPU6-GFP-Neo-Slug载体并转染A549细胞,转染率达90%。与pNeg-shRNA组和空白对照组相比,pSlug-shRNA组A549细胞中Slug mRNA\[（0.23±0.01）vs（0.97±0.08）、（1.0±0.09）,P＜0.05\]和蛋白\[（0.20±0.09 ）vs（1.0±0.32）、（1.13±0.26）,P＜0.05\]表达量显著降低;细胞增殖抑制率明显上升\[（35.3±5.4）% vs（1.5±0.2）%、（3.3±0.7）%,均P< 0.01\];细胞增殖指数显著降低 \[（32.92±0.69）% vs（48.19±0.71）%、（42.88±0.75）%,均P<0.05\],并且处于G1期细胞数明显增多\[（67.08±092）% vs（52.81±0.78）%、（56.12±0.73）%,均P<0.05\];细胞侵袭能力显著降低\[穿透基底膜细胞数：（55±9）vs（169±12）、（173±15）,均P<0.01\]。结论: pGPU6-GFP-Neo-Slug转染肺癌A549细胞能有效下调Slug基因的表达,从而抑制A549的增殖侵袭能力、阻滞细胞周期于G1期。     

米托蒽醌通过诱导钙网蛋白的表达抑制黑素瘤的生长

目的：观察米托蒽醌（mitoxantrone,MIT）对黑素瘤B16细胞钙网蛋白（calreticulin, CRT）表达的影响,探讨高表达CRT的B16细胞膜抗原疫苗的免疫效果及其机制。方法：不同剂量MIT处理B16细胞,免疫荧光法检测B16细胞CRT的表达。以B16细胞建立小鼠荷瘤模型,用不同剂量的MIT治疗荷瘤小鼠,观察MIT对黑素瘤生长及肿瘤组织中CRT表达的影响。制备B16细胞膜蛋白和MIT处理后B16细胞膜蛋白作为疫苗分别免疫小鼠,免疫组化检测小鼠移植瘤组织内免疫细胞的浸润情况,流式细胞术检测荷瘤小鼠脾脏中CD4+、CD8+T细胞比例的变化。结果：MIT可剂量依赖性地上调B16细胞表面CRT的表达,对照组B16细胞表面CRT为（29.40±3.57）%,高剂量MIT处理组为（72.20±2.94）%（P<0.05）;MIT促进移植瘤组织中CRT的表达,对照组为（3.21±1.37）,高剂量MIT组为（9.17±106）（P<0.05）。MIT有效抑制小鼠黑素瘤的生长（P<0.05,P<0.01）。与B16细胞膜蛋白疫苗相比,高表达CRT的MITB16细胞膜蛋白疫苗可明显上调小鼠黑素移植瘤组织中的DCs和T细胞的数量,以及脾脏细胞中CD4+、CD8+T细胞的比例（P<0.05）。结论：MIT能够上调CRT在B16细胞表面的表达,高表达CRT的B16细胞膜蛋白疫苗能够提高肿瘤组织中浸润DCs和T细胞的数量,抑制黑素瘤的生长。     

上调 Notch－1基因对 U215细胞 AKT －mTOR 通路的影响

目的：观察上调 Notch －1基因对人胶质瘤 U251细胞生学物行为及 AKT －mTOR 信号通路的影响。方法：采用 pNL －NICD 慢病毒感染 U251细胞,以 RT －PCR 和 Western －Blot 检测 Notch －1基因 mRNA 和蛋白的表达,以 MTT 检测细胞增殖能力,流式细胞术检测细胞周期变化,Transwell 实验检测细胞侵袭能力,同时检测 Notch －1上调对 AKT、mTOR、P70S6K、4Ebp －1蛋白的影响。结果：与对照组比较,NICD 慢病毒转染72h后,Notch －1基因 mRNA 和蛋白表达明显增高（P ＜0．01）;Notch －1上调明显促进 U251细胞增殖、侵袭、促进细胞进入 S 期,增加周期蛋白 Cyclin D1、CDK －4的表达,促进 AKT、mTOR 蛋白磷酸化。结论：上调 Notch －1基因促进 U251细胞增殖、侵袭,其机制和活化 AKT －mTOR 通路有关。     

基因对胃癌MGC 803细胞的抑制作用及其可能的机制

目的:研究沉默乳腺癌相关抗原1（breast cancerassociated antigen 1,BRCAA1)基因对胃癌细胞株MGC803的抑制作用及其可能的机制。方法：构建BRCAA1基因shRNA载体，将构建的shRNABRCAA1质粒与阴性对照质粒shRNAN转染胃癌MGC803细胞，24 h后用荧光显微镜观察转染效率，实时定量PCR检测 BRCAA1和GAPDH基因mRNA表达水平。MTT法检测转染后24、48与72 h的细胞增殖水平，AnnxinV PE/7AAD检测转染24 h后的细胞凋亡水平，Western blotting检测转染48 h后细胞的凋亡相关蛋白表达水平。结果：BRCAA1 siRNA表达质粒转染MGC803细胞24 h 的转染效率为（81.2±2.6）％ 。转染后48 h MGC803细胞的BRCAA1 mRNA水平下降了61.4％，MGC803细胞增殖的抑制率达45.0%，转染siRNA细胞的凋亡率明显高于未转染细胞和对照质粒转染细胞\[（14.4±１.6）% vs（5.4±2.0）％，（4.4±2.5）％，P<0.05\]。转染siRNA细胞的凋亡相关蛋白Rb与Bax的表达量显著增加（P<0.05），Bcl2的表达量显著减少（P<0.05）。结论：BRCAA1基因的沉默可有效抑制人胃癌MGC803细胞的增殖和诱导细胞凋亡，其机制与其促进Rb和Bax蛋白表达、抑制Bcl2蛋白表达有关。     

mTOR抑制剂FIM-A对人骨肉瘤细胞株MG-63的抑制作用及其机制

目的： 观察新型哺乳动物雷帕霉素靶蛋白（mammalia target of rapamycin,mTOR）抑制剂含磷西罗莫司衍生物FIM-A对人骨肉瘤MG-63细胞增殖及凋亡的影响。 方法： 不同浓度（1×10-9~1×10-5 mol/L） FIM-A处理MG-63细胞后,采用CCK-8法检测MG-63细胞的增殖,流式细胞术检测MG-63细胞周期和凋亡情况,ELISA法检测血管内皮细胞生长因子（vascular endothelial cell growth factor,VEGF）和低氧诱导因子（hypoxia inducible factor-1α,HIF-1α）的分泌量,RT-PCR和Western blotting分别检测FIM-A对MG-63细胞中mTOR、p70核糖体S6激酶（p70S6 kinase protein,p70s6k）及4E结合蛋白1（4E-binding protein 1,4E-BP1）mRNA和蛋白表达的影响。 结果： 与人成骨hF-OB1.19细胞相比,人骨肉瘤MG-63细胞中mTOR、p70s6k及4E-BP1 mRNA的表达水平明显升高（P<0.05）。FIM-A可有效抑制MG-63细胞的增殖（P<0.05）,且呈剂量依赖性（r=0940, P<0.01)。1×10-6 mol/L FIM-A 处理24 h后与对照组相比,G0/G1期MG-63细胞比例明显增加\[（56.4±3.2）% vs （43.4±6.9）%,P<0.05\],而MG-63细胞的凋亡率没有明显改变。不同浓度FIM-A作用24 h后,MG-63细胞中HIF-1α和VEGF表达均明显低于对照组（P<0.05）,且具有剂量依赖性（HIF-1α,r=-0.988, P<0.01; VEGF, r=-0.998, P<0.01)。同时,FIM-A对MG-63细胞中mTOR（r=-0.919,P<0.01）、p70s6k（r=-0.843,P<0.01）及4EBP1（r=-0.818,P<0.01）蛋白的磷酸化也具有浓度依赖性抑制作用。 结论： FIM-A能抑制人骨肉瘤MG-63细胞的增殖,并阻滞细胞周期于G0/G1期,其机制可能与影响mTOR信号通路蛋白磷酸化有关。     

沉默FOXQ1基因抑制肝细胞癌SMMC-7721细胞迁移侵袭能力

目的：探讨沉默叉头框蛋白Q1(forkhead box Q1,FOXQ1)基因后对肝细胞癌（hepatocellular carcinoma,HCC）SMMC-7721细胞迁移侵袭能力的影响及其机制。方法: 制备FOXQ1-shRNA、NC-shRNA重组慢病毒,将其感染到SMMC-7721细胞中;实验设干扰组、阴性对照组和空白组,用Transwell小室法检测细胞迁移、侵袭能力;利用qRT-PCR和Western blotting法检测SMMC-7721细胞中FOXQ1、MMP-2和MMP-9mRNA和蛋白的表达。结果: 随着肝癌SMMC-7721细胞的迁移侵袭能力的增强,FOXQ1的表达逐渐增加;干扰组较阴性对照组与空白组FOXQ1表达水平降低\[（0.34±0.03）vs（0.89±007）和（0.84±0.05）,P<0.05\];沉默FOXQ1基因后,SMMC-7721细胞的迁移侵袭能力显著下降\[(9.67±1.15) vs （25.67±208）和(27.33±2.52),P<0.05\],MMP-2与MMP-9表达水平下降\[MMP-2：(0.35±0.04) vs (0.61±0.05)和(065±008);MMP-9： (0.40±0.05) vs (0.73±0.07)和(0.77±0.06),均P<0.05\]。结论: 沉默FOXQ1基因的表达能够抑制肝癌SMMC-7721细胞的迁移、侵袭能力,其机制可能与MMP-2与MMP-9的表达下调有关。     

Biomarkers in clear cell renal cell carcinoma

The treatment of advanced renal cell carcinoma (RCC) has evolved significantly following the identification of the von Hippel–Lindau (VHL) gene and the function of its protein, and subsequent development of antiangiogenic therapies. A series of clinical trials resulted in the approval of three new agents with significant activity in this disease. Additional studies are now underway to identify subsets of patients most likely to benefit. This article reviews the current therapy for advanced RCC and the development of biomarkers in RCC. This requires the identification of disease characteristics at a clinical, genetic and molecular level associated with response and/or surrogate measures of clinical benefit. Currently, a variety of prognostic factors (lactate dehydrogenase, performance status, disease-free interval, hemoglobin and calcium levels) are utilized to predict the survival of RCC patients. The use of validated biomarkers in either serum/plasma, urine or tissue could enhance this process, as well as define at the molecular and genetic levels, factors associated with response to therapy and/or the development of resistance. Examples include plasma VEGF levels, VHL gene mutation status and carbonic anhydrase IX levels in tumor tissue, among others. Validation of such biomarkers is crucial in order for them to be clinically useful.     

Biomarkers in clear cell renal cell carcinoma

The treatment of advanced renal cell carcinoma (RCC) has evolved significantly following the identification of the von Hippel-Lindau (VHL) gene and the function of its protein, and subsequent development of antiangiogenic therapies. A series of clinical trials resulted in the approval of three new agents with significant activity in this disease. Additional studies are now underway to identify subsets of patients most likely to benefit. This article reviews the current therapy for advanced RCC and the development of biomarkers in RCC. This requires the identification of disease characteristics at a clinical, genetic and molecular level associated with response and/or surrogate measures of clinical benefit. Currently, a variety of prognostic factors (lactate dehydrogenase, performance status, disease-free interval, hemoglobin and calcium levels) are utilized to predict the survival of RCC patients. The use of validated biomarkers in either serum/plasma, urine or tissue could enhance this process, as well as define at the molecular and genetic levels, factors associated with response to therapy and/or the development of resistance. Examples include plasma VEGF levels, VHL gene mutation status and carbonic anhydrase IX levels in tumor tissue, among others. Validation of such biomarkers is crucial in order for them to be clinically useful.     

Non-small and small cell lung carcinoma cell lines exhibit cell type-specific sensitivity to edelfosine-induced cell death and different cell line-specific responses to edelfosine treatment

The unique signal transduction pathways that distinguish non-small cell lung carcinoma (NSCLC) from small cell lung carcinoma (SCLC) are poorly understood. We investigated the ability of edelfosine, an inhibitor of phosphatidylinositol-specific phospholipase C (PLC) to inhibit cell viability among four NSCLC cell lines and four SCLC cell lines. The differential sensitivity of cells to edelfosine's cytostatic and cytotoxic effects has been attributed to edelfosine-induced changes in the activities of many enzymes, including c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinases (ERK), p38 kinase, and poly(ADP-ribose) polymerase (PARP). To investigate the role of these enzymes in edelfosine-induced cytotoxicity, we correlated edelfosine-induced changes in enzyme activity and cell viability among the different NSCLC and SCLC cell lines. We found that NSCLC cells are much more susceptible to the cytotoxic effects of this drug than are SCLC cells. Three out of the four edelfosine-sensitive NSCLC cell lines (NCI-H157, NCI-H520, NCI-H522) exhibit G2/M arrest, significant apoptosis and some degree of JNK activation in response to drug treatment. In contrast, none of the SCLC cell lines exhibit edelfosine-induced G2/M arrest or significant apoptosis. A comparison of the edelfosine-induced effects among the sensitive and resistant lung cancer lines indicates that there is little correlation between edelfosine-induced cytotoxicity and altered activities of JNK, ERK, p38, or cleavage of PARP. These results demonstrate that edelfosine-induced changes in JNK, ERK, p38, or PARP are not good predictors of cell susceptibility to edelfosine-induced cytotoxicity. Thus, edelfosine-induced inactivation of PLC may disrupt signaling cascades downstream of PLC that are unique to individual cellular environments. These findings also identify edelfosine as one of the few potential chemotherapeutic agents that has a greater cytotoxic effect against NSCLC cells than SCLC cells.     

A human squamous cell carcinoma cell line.

An epithelial cell line COLO 16 has been established from a human squamous carcinoma, characterized and maintained for over two years. The cells produce a parathyroid-like hormone and carcinoembryonic antigen. The line is definitely not a "HeLa contaminant." The cell line is available to other investigators.     

Allogeneic stem cell transplantation for renal cell carcinoma

Allogeneic hematopoietic stem cell transplantation from a compatible donor has been utilized as adoptive immunotherapy in metastatic, cytokine-refractory renal cell carcinoma (RCC). Since the year 2000, several investigators have established that RCC is susceptible to a graft-versus-tumor effect: they reported that patients with renal cancer may have partial or complete disease responses, in the 20-40% range, after allogeneic transplantation following a reduced-intensity regimen. However, transplant-related mortality is still high in the 10-20% range, and responses are rarely durable. Experimental evidence suggests that donor-derived T cells and natural killer cells are the main mediators of the graft-versus-RCC effect upon allogeneic hematopoietic stem-cell transplantation. Isolation of CD8(+) cytotoxic T lymphocyte clones recognizing several target antigens of graft-versus-RCC effect (minor histocompatibility antigens on RCC cells; a peptide epitope derived from human endogenous retrovirus type E; the tumor-associated antigen encoded by the Wilms' tumor 1 gene) has increased our knowledge of the disease and has opened up the possibility of antigen-specific adoptive cell therapy. The introduction in the clinic of molecularly targeted agents that interfere with neoangiogenesis, both monoclonal antibodies and small tyrosine-kinase inhibitor molecules (e.g., sunitinib, sorafenib and bevacizumab), has decreased the use of allogeneic transplantation. Although not curative, novel targeted agents may be combined with allogeneic transplantation or with adoptive cell therapy in order to maximize the chances of cure.