p53N15融合肽转染肺腺癌细胞系H1299的抗肿瘤作用

目的 探讨p53N15融合肽转染对肺腺癌细胞H1299体外生长的抑制作用.方法 通过腺体相关病毒(adeno-associated virus AAV)载体把p53N15融合肽高效导入p53缺失肺腺癌H1299细胞系,应用相差倒置显微镜观察、MTT细胞活性试验及流式细胞仪技术分析p53N15对肺癌细胞的抑制作用.结果 p53N15融合肽在H1299细胞中得到了高效表达并发挥明显效应,表现为显微镜下,重组病毒转染72 h可见大片细胞死亡.MTT试验分析,重组病毒转染组细胞活性明显降低.流式细胞仪技术显示,重组病毒转染组可见大量死亡细胞.结论 p53N15融合肽转染可明显抑制肺腺癌细胞H1299的体外生长.     

p53N15融合肽转染肺腺癌细胞系H1299的抗肿瘤作用

目的 探讨p53N15融合肽转染对肺腺癌细胞H1299体外生长的抑制作用.方法 通过腺体相关病毒(adeno-associated virus AAV)载体把p53N15融合肽高效导入p53缺失肺腺癌H1299细胞系,应用相差倒置显微镜观察、MTT细胞活性试验及流式细胞仪技术分析p53N15对肺癌细胞的抑制作用.结果 ...     

联合自杀基因及内皮抑素基因双靶点体外治疗膀胱癌

目的 观察基因重组腺相关病毒自杀基因及内皮抑素(ES)联合基因体外治疗膀胱癌的效果.方法 (1)通过基因重组腺相关病毒(rAAV)-增强绿色荧光蛋白(EGFP)转染膀胱肿瘤T24细胞,确定rAAV对T24细胞的转染效率;(2)通过rAAV-胸苷激酶(TK)-核糖体插入位点(IRES)-ES(简称rAAV-TIE)体外转染T24、HUVEC细胞,MTT法、流式细胞仪等方法 来检测诱导凋亡作用.结果 (1)rAAV-EGFP转染T24细胞后可以表达携带的外源基因EGFP,感染效率约为62%;(2)rAAV-TK、rAAV-TIE转染T24细胞72 h后,流式细胞仪检测结果 显示.rAAV-TK、rAAV-TIE两组凋亡率分别是37.02%和32.14%,明显高于空病毒转染组(7.90%)和空白对照组(0.30%).结论 rAAV-TIE可有效抑制膀胱癌的血管生成和肿瘤的生长,能够双靶点基因治疗膀胱肿瘤.     

基因重组rAAV-TK治疗膀胱癌

目的 探讨基因重组rAAV-TK基因治疗膀胱癌的效果.方法 (1)通过rAAV-EG-FP转染膀胱肿瘤T24细胞,来确定重组腺相关病毒对该细胞的转染情况及转染效率;(2)通过rAAV-TK体外转染T24膀胱肿瘤细胞,MTT、流式细胞仪等方法来检测对T24细胞凋亡的诱导作用;(3)构建裸鼠膀肮肿瘤模型,分析rAAV-TK基因治疗膀胱痛的体内效果.结果 (1)在T24细胞中可以表达携带的外源基因EGFP;(2)rAAV-TK可以稳定感染T24细胞;(3)rAAV-TK转染124细胞72 h后,流式细胞仪检测结果显示,细胞凋亡率是34.12%,明显高于空病毒转染组和空白对照组;(4)瘤内注射rAAV-TK大约9 d后,肿瘤生长受到显著抑制,治疗结束后:各组肿瘤的体积分别是:rAAV-TK组(0.71±0.11)cm3、rAAV-MCS组(1.27±0.13)cm3和空白对照组(1.24±0.17)cm3(P<0.05).结论 体外和体内实验表明rAAV-TKⅨ可有效抑制膀胱肿瘤的生长,能够有效基因治疗膀胱肿瘤.     

肝癌特异性多靶点慢病毒的体外实验研究

目的 研究anti-AFP scFv(抗AFP单链抗体)介导的慢病毒(lentivirus)载体对表达AFP肝癌细胞特异性基因转移以及双靶点基因系统对肝癌细胞生长的抑制作用.方法 用脂质体Lipofectamine 2000将目的基因转移载体、包装结构及包膜结构质粒共转染包装细胞293T,大量收集病毒上清,过滤、浓缩.用携带AFP-WtP53-pPRIME-miR30-shRNA-IGF1R融合基因的慢病毒体外转染培养的肝癌细胞HEP3B.荧光显微镜下观察感染效果,用PCR、Western blotting鉴定WtP53、miR30-shRNA-IGF1R在细胞中的整合转录结果.CCK8观察重组慢病毒对肝癌细胞生长的影响,TUNEL检测细胞凋亡.结果 成功构建anti-AFP scFv介导的慢病毒;滴度为4.58×109 PFU/ml;PCR、Western blotting均显示阳性条带,证明anti-AFP scFv介导的慢病毒在靶细胞中整合且转录表达.重组慢病毒对肝癌细胞的生长有明显的抑制作用且有促进细胞凋亡的作用.结论 anti-AFPscFv介导的慢病毒可将双靶点基因系统高效靶向性转染、杀伤肝癌细胞.     

p27^kipl高表达对前列腺癌PC-3细胞增殖和侵袭转移的影响

目的探讨外源性人p27kip1的高表达对前列腺癌PC-3细胞增殖和侵袭能力的影响.方法利用携带人p27kip1基因的腺病毒(Ad-p27kip1)体外转染人前列腺癌PC-3细胞,逆转录-聚合酶链反应(RT-PCR)、Western印迹法分别检测目的基因不同水平的表达,通过细胞生长试验、流式细胞仪分析技术以及Boyden小室法检测PC-3转染前后细胞增殖、细胞周期、细胞凋亡和细胞体外侵袭力的变化.以Ad-X-gal病毒作为对照.结果 RT-PCR、Western印迹法检测转染Ad-p27kip1后PC-3细胞的p27kip1-mRNA(320bp)、p27蛋白(27×103)表达阳性,转染后对PC-3细胞的生长有抑制作用,出现明显的G0-G1期阻滞,早期细胞凋亡率有所增加,与对照组比较差异有显著性,Boyden小室法检测转染后体外侵袭力受到明显抑制.结论重组腺病毒介导的人p27kip1基因在体外对前列腺癌细胞系PC-3的细胞增殖和侵袭力有明显抑制作用,可望作为前列腺癌基因治疗的有效工具.     

腺病毒介导的p16基因转染对膀胱癌细胞生长影响的研究

目的　探讨复制缺陷型腺病毒介导的 p16基因转染对人膀胱癌细胞生长的影响。 　方法　将 p16重组腺病毒 (Ad p16 )感染p16蛋白表达阴性的人膀胱移行细胞癌T2 4细胞株 ,Ad LacZ、X gal染色法检测重组腺病毒的转染效率 ;Westernblot法检测 p16蛋白的表达 ;MTT法及流式细胞术评估Ad p16对T2 4细胞增殖的影响。　结果　在感染复数 (MOI)为 5 0时 ,重组腺病毒对T2 4细胞的转染率达 97% ;此Ad p16在T2 4细胞中可获高效表达 ;与转染Ad LacZ组及未转染组相比 ,转染Ad p16组T2 4细胞生长受到明显抑制 (P <0 .0 5 ) ,细胞周期分析表明生长抑制主要发生在G1 S节点。　结论　腺病毒载体可有效地将外源 p16基因导入T2 4细胞 ;p16基因重组腺病毒载体转染能抑制T2 4细胞的生长。     

腺相关病毒载体介导p27Kip1基因转染骨肉瘤MG-63细胞的研究

目的 观察p27Kip1基因转染后对骨肉瘤MG-63细胞增殖和生存能力的影响.方法 重组质粒在内的三质粒共转染包装、收集腺相关病毒颗粒,检测病毒滴度并感染MG-63细胞,细胞免疫组织化学检测p27Kip1基因的表达,并行细胞增殖实验、细胞周期分析,探讨p27Kip1基因对骨肉瘤MG-63细胞的体外作用.结果 三质粒成功共转染293细胞,X-gal染色观察转染率为60%;采用CPE法(微量全细胞病变法)检测病毒滴度1.6×108 PFU/ml;细胞免疫细胞化学鉴定p27Kip1基因高表达;细胞生长曲线显示转染组细胞增殖明显减慢;流式细胞仪观察转染AAV-p27Kip1组细胞周期见S、G2期细胞比例明显降低,G0/G1期细胞比例增高.结论 p27Kip1基因重组腺相关病毒感染骨肉瘤MG-63细胞后能高表达目的 基因,并阻滞细胞于G1/S期,从而显著抑制骨肉瘤MG-63细胞增殖.     

野生型p53基因对不同内源性p53状态的肝癌细胞株生长的影响

目的探讨外源性野生型p53(wild-type p53,WT-p53)基因对具有不同内源性p53功能状态肝癌细胞生长的影响.方法通过表达WT-p53的重组腺病毒载体(Ad-p53),将p53基因导入具有不同内源性p53功能状态的肝癌细胞株Bel-7402、QGY-7701和PLC/PRF/5中,用MTT法检测Ad-p53对各细胞株生长的影响,流式细胞仪分析各组细胞中DNA含量及凋亡的比例.结果当取40、200、800 MOI值的表达p53的腺病毒分别转染PLC/PRF/5、Bel-7402和QGY-7701细胞时,72 h后行MTT检测,OD值分别为在 PLC/PRF/5细胞,空载体(Ad-LacZ)组0.98±0.16,Ad-p53组0.02±0.00(P＜0.01);在Bel-7402细胞Ad-LacZ组1.04±0.23,Ad-p53组0.10±0.02(P＜0.01);而在QGY-7701细胞Ad-LacZ组1.88±0.24,Ad-p53组1.86±0.19(P>0.05).细胞周期分析显示,在PLC/PRF/5,表现为既诱导细胞凋亡,又诱导细胞周期阻滞.在Bel-7402,表现为诱导细胞周期阻滞.结论外源性p53对肝癌细胞生长的抑制可能与内源性p53功能状态无关.     

人肿瘤转移抑制基因NM23-H1抑制卵巢癌转移机制体内体外实验研究

目的研究卵巢癌的人转移抑制基因NM23H1转移抑制的机制。方法首先构建由人肿瘤转移抑制基因NM23H1及真核细胞表达载体PcDNA3.1/zero构建成重组质粒PcDNA.NM23H1,并将其转染到高转移卵巢癌细胞株HO8910。体外实验:通过细胞DNA合成的流式细胞仪分析,以发现NM23H1对癌细胞生长的改变采用成集落实验,以观察转染组对转化生长因子(TGF)β刺激形成的集落数及细胞数并与对照组对比。同时检测转染组对化疗药物顺铂的敏感性。体内实验:将转染细胞注射于裸鼠皮下观察成瘤时间和肿瘤转移情况。结果NM23H1对卵巢癌细胞生长有一定抑制作用;实验组与对照组比较,实验组所形成的集落少,集落中细胞数目也少;被转染的细胞比对照组对顺铂更敏感,细胞死亡数多;裸鼠体内实验表明NM23H1对卵巢癌有抑制生长作用,主要对淋巴道转移有一定程度的抑制作用。结论NM23H1经高转移卵巢癌细胞株的体外实验发现对卵巢癌细胞生长及转移均有一定抑制作用;可增加对顺铂治疗的敏感性;体内实验表明,NM23H1可抑制癌瘤生长,对卵巢癌淋巴道转移有一定抑制作用。     

Aberrant Expression and Mutation-Inducing Activity of AID in Human Lung Cancer

Background

Activation-induced cytidine deaminase (AID) is expressed in B lymphocytes and triggers antibody diversification. Recent reports have indicated that the constitutive expression of AID in mice causes not only lymphomas, but also cancers of some organs including the lung, prompting us to investigate the expression and effect of AID on human lung cancer.

Materials and Methods

We examined AID mRNA expression in 17 lung cancer cell lines and 51 primary lung cancers using a quantitative RT-PCR analysis. Next, we established H1299 lung cancer cells stably overexpressing AID and performed a supF forward mutation assay. We then examined AID protein expression and p53 mutation in 129 primary lung cancers by an immunohistochemical analysis and PCR-SSCP and sequencing analyses, respectively.

Results

Aberrant mRNA expression of AID was detected in 29% (5 of 17) of the lung cancer cell lines and 31% (16 of 51) of the primary lung cancers. AID-overexpressing H1299 clones showed a 5.0- to 6.1-fold higher mutation frequency than an empty vector-transfected H1299 clone, and about half of the AID-induced mutations were base substitutions, indicating that AID induces gene mutations in lung cancer cells. Furthermore, an association was found between the AID protein expression level and the p53 mutation status in an analysis of 129 primary lung cancers. A further expression analysis revealed that a portion of AID is localized at the centrosomes.

Conclusion

Our current findings suggest that the aberrant expression of AID may be involved in a subset of human lung cancers as a result of its mutation-inducing activity.

     

Checkpoint kinase 1 protein expression indicates sensitization to therapy by checkpoint kinase 1 inhibition in non–small cell lung cancer

Background

When presenting with advanced stage disease, lung cancer patients have <5% 5-y survival. The overexpression of checkpoint kinase 1 (CHK1) is associated with poorer outcomes and may contribute to therapy resistance. Targeting CHK1 with small-molecule inhibitors in p53 mutant tumors might improve the effectiveness of chemotherapy and radiotherapy in non–small cell lung cancer (NSCLC).

Methods

We evaluated CHK1 messenger RNA and protein levels in multiple NSCLC cell lines. We assessed cell line sensitization to gemcitabine, pemetrexed, and radiotherapy by CHK1 inhibition with the small molecule AZD7762 using proliferation and clonogenic cell survival assays. We analyzed CHK1 signaling by Western blotting to confirm that AZD7762 inhibits CHK1.

Results

We selected two p53 mutant NSCLC cell lines with either high (H1299) or low (H1993) CHK1 levels for further analysis. We found that AZD7762 sensitized both cell lines to gemcitabine, pemetrexed, and radiotherapy. Chemosensitization levels were greater, however, for the higher CHK1 protein expressing cell line, H1299, when compared with H1993. Furthermore, analysis of the CHK1 signaling pathway showed that H1299 cells have an increased dependence on the CHK1 pathway in response to chemotherapy. There was no increased sensitization to radiation in H1299 versus H1993.

Conclusions

CHK1 inhibition by AZD7762 preferentially sensitizes high CHK1 expressing cells, H1299, to anti-metabolite chemotherapy as compared with low CHK1 expressing H1993 cells. Thus, CHK1 inhibitors may improve the efficacy of standard lung cancer therapies, especially for those subgroups of tumors harboring higher expression levels of CHK1 protein.     

腺病毒介导p53基因联合肿瘤坏死因子对H22腹水瘤的协同作用

目的评价p53腺病毒注射液（AD-p53）与肿瘤坏死因子（TNF）联合腹腔给药对H22腹水瘤模型的协同抑制作用。方法建立H22腹水瘤的昆明小鼠模型，48h后以AD-p53、TNF、生理盐水等腹腔注射，治疗周期为1周，治疗后测量腹围、体重，计量腹水，计数瘤细胞数，以流式细胞分析检测瘤细胞凋亡、死亡比例及细胞周期。结果AD-p53腹腔给药1周，出现瘤细胞G0／G1期阻滞；其和TNF联用后，未生成腹水的小鼠增多；在生成腹水的小鼠，腹水量和瘤细胞数均较单用时明显减少。结论AD-p53可阻滞瘤细胞周期，抑制增殖，联合TNF腹腔给药，在抑制腹水瘤时具有协同作用。     

Adenoviral melanoma differentiation-associated gene 7 induces apoptosis in lung cancer cells through mitochondrial permeability transition-independent cytochrome c release

OBJECTIVE: Melanoma differentiation-associated gene 7 is a novel tumor suppressor gene that induces apoptosis in lung cancer cells when delivered by adenoviral gene transfer as Ad-mda7. The mechanisms of action are not well defined but may involve release of cytochrome c from the mitochondria with subsequent caspase activation. METHODS: The lung cancer cell lines A549 and H1299 were transduced with Ad-mda7, adenovirus containing the gene for p53 (Ad-p53), and control adenoviral luciferase vectors. Staurosporine was used as a positive control to induce cytochrome c release through mitochondrial permeability transition-dependent pores, whereas cyclosporine (INN: ciclosporin) was used to specifically inhibit these mitochondrial permeability transition-dependent pores. Apoptosis was evaluated with fluorescence-activated cell sorting analysis of subdiploid populations and mitochondrial membrane potential changes with tetramethylrhodamine ethylester perchlorate. RESULTS: Melanoma differentiation-associated gene 7, transduced by Ad-mda7 into H1299 and A549 lung cancer cells, resulted in sharp increases in cytosolic cytochrome c levels followed by induction of apoptosis and cellular death. The release of cytochrome c from the mitochondria occurred without changes in the mitochondrial membrane potential. Unlike staurosporine treatment, transduction with Ad-p53 and Ad-mda7 caused releases of cytochrome c and apoptosis that were not blocked by cyclosporine, suggesting a mitochondrial permeability transition pore-independent pathway. CONCLUSIONS: Ad-mda7 induces apoptosis in lung cancer cells through mitochondrial cytochrome c release in a process that is not dependent on mitochondrial membrane potential changes and occurs through mitochondrial permeability transition-independent pores. This unique mechanism of action may allow treatment of patients with lung cancer resistant to mitochondrial permeability transition-dependent cell death processes.     

丁酸钠对人胰腺癌细胞ASPC-1生长的影响及其机制的研究

目的 探讨丁酸钠对人胰腺癌ASPC-1细胞生长的影响并探讨其作用机制.方法 使用不同浓度丁酸钠处理ASPC-1细胞.MTT法观察肿瘤细胞的增殖;流式细胞仪检测细胞凋亡和细胞周期的变化;Western印迹法检测细胞内p21、p53、bcl-2、bax蛋白表达的变化,实时定量PCR检测p21和bcl-2的表达.结果 丁酸钠能明显抑制ASPC-1细胞的增殖,其作用具有明显的时间和剂量依赖性.丁酸钠处理24 h后ASPC-1细胞凋亡率明显提高(P＜0.05),S期细胞比例显著降低(P＜0.05),G0/G1期细胞比例显著升高(P＜0.05).p21、bax蛋白表达明显上调(P＜0.05);bcl-2蛋白的表达显著降低(P＜0.05);p53蛋白表达无明显变化(P＞0.05).结论 丁酸钠可以通过诱导胰腺癌细胞的凋亡和周期阻滞而抑制癌细胞生长;其发生机制可能与下调抗凋亡基因bcl-2、上调促凋亡基因bax和肿瘤抑制基因p21的表达有关.

Abstract：

Objective To investigate the effects of sodium butyrate(NaBT) on proliferation of human pancreatic cancer cell line ASPC-1 and explore the possible mechanism. Methods The methylthiazolyl tetrazolium assay (MTT) method was used to detect cell proliferation and draw a curve. The cell apoptosis and cell cycle were determined with flow cytometry. Western blot was used to study the effect NaBT on the pancreatic cancer cells and explore its mechansim. Real-time PCR was employed to assess the expression levels of p53, p21, bcl-2 and cell cycle regulation gene p21. Results After incubation with different concentrations of NaBT for 24 to 72 h, ASPC-1 cell proliferation was inhibited dramatically. NaBT induced an increase of G0/G1 phase cells and a significant decrease in the ratio of S phase cells. The expression of p21 and bax was up-regulated at protein and mRNA level. The expression of bcl-2 was down-regulated at protein and mRNA level. There was no significant difference in the expression of p53 at protein and mRNA level. Conclusion TSA-induced growth inhibition is associated with a block in the G0/G1 phase and apoptosis, which may occur through down-regulating the expression of apoptosis gene bcl-2 and up-regulating the expression of cell cycle regulation gene p21and pro-apoptotic gene bax.     

以白细胞介素4-受体为靶标的胰腺癌靶向治疗研究

目的 检测白细胞介素4受体(IL-4R)在胰腺癌组织及人胰腺癌细胞株中的表达,观察以抗白细胞介素-4受体单抗(MAIL4R)为载体构建的免疫毒素MAIL4R-CTX对胰腺癌细胞的靶向杀伤作用.方法 应用免疫组织化学检测IL-4R在26例胰腺癌组织、15例胰腺正常组织中的表达;免疫细胞化学染色检测IL-4R在人胰腺癌PANC-1、BxPC-3细胞和人肺腺癌H1299细胞中的表达;采用噻唑蓝(MTT)法观察MAIL4R、眼镜蛇毒细胞毒素(CTX)、免疫毒素MAIL4R-CTX对体外培养PANC-1,BxPC-3细胞和H1299细胞生长的影响.结果 IL-4R在26例胰腺癌组织中均呈不同程度的阳性表达,而15例胰腺正常组织中仅1例呈弱阳性表达,余均为阴性表达;人胰腺癌PANC-1,BxPC-3细胞均表达IL-4R,H1299细胞不表达IL-4R;CTX对PANC-1,BxPC-3和H1299细胞均有明显抑制作用,但对3株细胞的抑制率差异无统计学意义(P＞0.05);MAIL4R对PANC-1、BxPC-3和H1299细胞均无明显抑制作用;MAIL4R-CTX对过表达IL-4R的BxPC-3和PANC-1细胞的生长具有显著的抑制作用,并且为剂量依赖性,而对低表达IL-4R的H1299细胞不敏感,在浓度为18.75 mg/L,作用4h时PANC-1和BxPC-3细胞分别有86.4%和95.2%被杀伤,H1299细胞仅死亡26.8%(P＜0.01).结论 IL-4R过表达于胰腺癌组织和胰腺癌细胞株,而低表达于正常胰腺组织中,免疫毒素MAIL4R-CTX在体外对过表达IL-4R的细胞株PANC-1、BxPC-3有靶向性杀伤作用.     

腺病毒载体介导的早幼粒细胞白血病基因生长抑制因子诱导胃癌细胞凋亡的机制研究

目的 探讨腺病毒载体介导的早幼粒细胞白血病基因（PML）生长抑制因子诱导胃癌细胞凋亡作用的机制。方法 将人PML全长cDNA插入穿梭质粒pSGCMV，再与腺病毒骨架质粒pPE3共转染293细胞后获得重组病毒。用重组病毒感染胃癌细胞系SGC-7901，采用噻唑蓝比色法、流式细胞术以及免疫细胞化学法对p53和bcl-2在肿瘤细胞内的表达以及细胞凋亡的定性与定量指标进行检测。结果 经腺病毒介导的PML处理的SGC-7901细胞生长受到明显抑制，凋亡细胞发生率升高，且与MOI值呈正相关，MOI值由5增加到20，细胞的生长抑制率从22．4％增加到38．5％，而细胞凋亡率从37．2％增加到49．8％。经腺病毒介导的PML处理的SGC-7901细胞内p53蛋白表达较对照组明显增加，bel-2蛋白的表达则无明显变化。结论 腺病毒介导的PML对胃癌细胞的杀伤主要是通过诱导细胞凋亡，p53蛋白高表达为其诱发胃癌细胞凋亡的机制之一。