核因子-κB/p65表达下调对舌鳞状细胞癌裸鼠移植瘤中bcl-2和bax表达的影响

目的:本实验旨在探讨下调核因子-κB(nuclear factor-kappa B,NF-κB)/p65亚单位的表达对舌鳞状细胞癌裸鼠移植瘤生长及细胞凋亡相关基因bcl-2和bax表达的影响。方法:应用舌鳞状细胞癌Tca8113细胞建立舌鳞状细胞癌裸鼠移植瘤模型。将针对p65的小干扰RNA(small interfering RNA,siRNA)接种荷瘤裸鼠,观察下调NF-κB/p65表达后荷瘤裸鼠的生长情况;采用TUNEL法检测肿瘤组织中的细胞凋亡情况;进一步应用RT-PCR和Western印迹法检测肿瘤组织中p65、bcl-2和bax的mRNA及蛋白表达变化。结果:经p65siRNA治疗后,肿瘤的生长明显受到抑制(P<0.05);TUNEL结果表明,p65siRNA组肿瘤细胞明显发生凋亡;此外,p65siRNA组裸鼠肿瘤组织p65和bcl-2的mRNA及蛋白表达明显下调,而bax的mRNA及蛋白表达显著上调,差异均有统计学意义(均P<0.05)。结论:NF-κB/p65亚基可能在舌鳞状细胞癌的细胞凋亡中发挥重要作用。     

人参皂苷Rg3对人胰腺癌细胞Pim-3及Bad凋亡蛋白表达的影响

背景与目的：人参皂苷Rg3是一种抗肿瘤中药单体,有研究表明人参皂苷Rg3对肝癌、肺癌、结肠癌、胰腺癌等肿瘤细胞的浸润具有明显抑制作用。本实验目的是研究人参皂苷Rg3对人胰腺癌细胞株PANC-1中原癌基因Pim-3及磷酸化Bad蛋白pBad（Ser112）、Bad（Serl36）表达的影响。方法：用浓度为0、10、20、40和80μmol／L的人参皂苷Rg3处理PANC-1细胞24h后,用四甲基偶氮唑盐（MTF）法检测人参皂苷Rg3对PANC-1细胞增殖的抑制作用;用倒置显微镜和流式细胞术观察人参皂苷Rg3对PANC-1细胞凋亡的诱导作用;用Western blot法检测经不同浓度人参皂苷Rg3处理后的PANC-1细胞中pim-3、Bad、pBad（Ser112）和pBad（Ser136）的表达;定向克隆Pim-3的发夹状寡核苷酸（shorthairpinRNA,shRNA）到真核表达载体形成重组质粒pSilencer3．1-HINeo—Pim-3shRNA．将重组质粒通过脂质体介导转染PANC-1细胞,采用AnnexinV／PI流式细胞分析法检测转染后PANC-1细胞的凋亡．用Westernblot法检测转染后PANC-1细胞的pim-3及pBad（Serl12）的表达。结果：10、20、40和80btmol／L的人参皂苷Rg3对PANC-1细胞增殖的抑制率分别为20．2％、33．4％、52．8％、65．3％;经10～80μmol／L的人参皂苷Rg3处理后PANC-1细胞呈现明显的凋亡形态学改变,80μmol／L人参皂苷Rg3处理PANC-1细胞24h后,与正常对照组细胞凋亡率（3．3±2．1）％比较,处理组细胞凋亡率（12．2±1．3）％增加（P〈0．05）;人参皂苷Rg3处理PANC-1细胞24h后,Bad总蛋白表达没有明显变化。pim-3和pBad（Ser112）的表达均随人参皂苷Rg3浓度的增加而逐渐减弱。PANC-1细胞中pBad（Ser136）不表达;Pim-3shRNA转染PANC-1细胞后．与正常对照组比较,转染组早期凋亡率和总凋亡率均增加[（11．5±3．7）％VS．（5．8±2．2）％,P〈0．01;（20．8±2．6）％VS．（13．0±4．1）％,P〈O．05],转染组pim-3及pBad（S     

转染 cdc25A-Fas嵌合基因表达载体体外诱发 Tca8113细胞凋亡的研究

背景与目的: Fas/FasL与口腔鳞癌的发生、发展相关.本研究旨在探讨 cdc25A-Fas嵌合基因表达载体诱导舌鳞癌 Tca8113细胞凋亡的作用.方法:用基因工程方法分别构建 pAdTrack-CMV-cdc25A-Fas( pCCF)和 pAdTrack-cdc25A-Fas( pCF)嵌合基因表达载体;脂质体法将 pCCF、 pCF、 pAdTrack-CMV分别转染 Tca8113细胞;报告基因绿色荧光蛋白( GFP)观察转染效率; Northern blot、 RT-PCR、 Western blot、免疫组化技术检测 Fas基因的转录及表达时序; DNA凝胶电泳带型分析( DNA agarose gel electrophoresis)、原位缺口末端标记 (TUNEL)、 Annexin V、流式细胞仪( flow cytometry, FCM)检测 Tca8113细胞凋亡.结果:( 1)嵌合基因表达载体 pCCF、 pCF转 染 Tca8113细胞的转染率为 15%左右,出现在转染后第 5～ 7天.( 2)转染第 3天, pCCF、 pCF组 Fas表达显著上调;第 3、 5、 7天均表达 Fas蛋白, Fas蛋白主要在胞膜和胞浆表达;表达 Fas蛋白的 Tca8113细胞呈现部分凋亡的形态特征. (3)pCCF和 pCF转染 2.5天 (60 h), Tca8113细胞开始出现凋亡,第 3天凋亡率达到最高约 25%,与对照组细胞比较具有显著性差异( P< 0.05), pCCF和 pCF比较无显著性差异( P >0.05). (4)流式细胞仪检测到绿色荧光蛋白表达细胞峰与凋亡细胞峰一致.结论:嵌合基因表达载体 pCCF和 pCF转染口腔鳞癌 Tca8113细胞可诱导细胞凋亡.     

化学修饰的siRNA对乳腺癌细胞VEGF基因表达抑制及凋亡的诱导作用

目的：体外水平探讨化学修饰的小干扰RNA（siRNA）介导的RNAi治疗乳腺癌的可行性。方法：选用阳离子脂质体Lipofectamine2000^TM作为转染试剂,将化学修饰的针对人VEGF基因的siRNA转染人类乳腺癌细胞株MCF-7。半定量RT—PCR和蛋白印迹试验分别检测转染前后细胞中VEGF、Bcl2和baxmRNA和蛋白水平表达的变化,Hoechst33258荧光染色分析细胞凋亡。结果：与未转染的正常细胞组相比,靶向VEGF基因的siRNA转染MCF-7后,细胞中VEGF及Bcl-2mRNA和蛋白表达水平显著降低,P〈0．01。bax基因的表达未发生明显变化,Bcl-2和bax比值下降。Hoechst33258荧光染色显示转染siRNA72h后细胞内可见凋亡小体。结论：化学修饰的siRNA介导的RNAi下调靶基因VEGF的表达,并对MCF-7细胞有明显的凋亡诱导作用。     

P75NTR 基因在舌鳞状细胞癌细胞凋亡中的作用及其机制

目的：探求p75神经营养因子受体（P75 NTR）基因在舌鳞状细胞癌细胞凋亡中的作用及其可能的分子作用机制。方法p75NTR 特异性小干扰 RNA（siRNA）转染 p75NTR 阳性舌鳞状细胞癌细胞;P75NTR 阳性舌鳞状细胞癌株 Tca8113细胞分为空白对照组、阴性对照组、实验组-776（转染siRNA-P75NTR-776）、实验组-1234（转染 siRNA-P75NTR-1234）。流式细胞仪双染色标记法检测转染率及细胞凋亡;荧光定量 PCR 检测 P75NTR 基因;Western blotting 检测各组 P75NTR 蛋白的表达;四甲基偶氮唑蓝法检测 siRNA 对细胞增殖的影响;细胞免疫荧光标记法观察核转录因子-κB（NF-κB）在细胞质及细胞核中的分布变化。结果测得转染效率为30％;实验组-776、实验组-1234与阴性对照组的凋亡率分别为（20．35±0．18）％、（12．32±1．51）％、（2．63±0．10）％,前两者与阴性对照组相比,差异有统计学意义（t ＝177．20,P ＜0．005;t ＝37．12,P ＜0．005）。P75NTR 基因干扰成功,实验组-776组的 P75NTR蛋白抑制率达31％。P75NTR-siRNA 干扰后实验组-776、实验组-1234与阴性对照组 Tca8113细胞存活率分别为70．02％、78．01％和95．81％,前两者与阴性对照组相比,差异有统计学意义（χ2＝235．3,P ＜0．001;χ2＝117．5,P ＜0．005）。实验组内 NF-κB 在细胞质内分布明显增多。结论P75NTR 能促进舌鳞状细胞癌细胞增殖或抑制其凋亡,其分子机制可能与阻碍 NF-κB 核内转运密切相关。     

Bcl-2 siRNA对胃癌细胞凋亡及其紫杉醇敏感性影响研究

目的:研究特异性siRNA对胃癌细胞的抑制作用,以及探讨采用RNA干扰技术下调Bcl-2基因能否增强SGC-7901胃癌细胞对紫杉醇的敏感性。方法:通过脂质体HiperFect将Bcl-2 siRNA转染入胃癌细胞SGC-7901;采用RT-PCR和蛋白印迹法检测Bcl-2 siRNA转染前后胃癌细胞Bcl-2基因表达的变化;用Annexin Ⅴ法及细胞周期分析法检测细胞凋亡;用MTS法观察细胞对药物紫杉醇敏感性的影响。结果:Bcl-2 siRNA组较空白对照组明显抑制Bcl-2 mRNA的表达水平,抑制率为(87.6±5.3)%,P=0.001;Bcl-2 siRNA组较空白对照组明显下调Bcl-2蛋白表达水平,抑制率为(85.7±3.6)%,P=0.003。Bcl-2 siRNA组、紫杉醇组和紫杉醇+Bcl-2 siRNA细胞总凋亡率分别为49.00%、46.10%和66.00%,联合用药组细胞凋亡率最强。Bcl-2siRNA+紫杉醇联合用药对SGC-7901细胞周期分析结果显示,联合用药组凋亡率为48.00%,Bcl-2 siRNA组和紫杉醇组分别为9.03%和21.50%。Bcl-2 siRNA组、阴性对照组和空白对照组的IC50分别(7.25±0.22)、(54.45±0.82)和(68.9±0.91)μg/L,Bcl-2 siRNA转染胃癌细胞SGC-7901对药物紫杉醇更敏感,其IC50值比阴性siRNA转染组降低86.7%,即对紫杉醇敏感性增加7.25倍。结论:靶向Bcl-2 siRNA可明显下调靶基因Bcl-2表达,促进SGC-7901细胞凋亡并能提高细胞对紫杉醇敏感性,为胃癌治疗提供新的策略。     

白细胞介素-8沉默对喉鳞状细胞癌细胞增殖和凋亡的影响及机制研究

目的探讨白细胞介素-8(IL-8)沉默对喉鳞状细胞癌细胞增殖和凋亡的影响及相关机制。方法将IL-8小干扰RNA(siRNA)和Lipofectamine 2000转染试剂转染至喉鳞状细胞癌Hep-2细胞作为实验组和NC组仅转染Lipofectamine 2000转染试剂的细胞作为,未做处理的细胞作为空白组。采用噻唑蓝(MTT)法检测细胞增殖能力,流式细胞仪检测细胞凋亡情况,蛋白质印迹法(Western blot)检测IL-8、蛋白激酶B(AKT)、磷酸化AKT(p-AKT)、cleaved caspase 3、B细胞淋巴瘤/白血病-2(Bcl-2)、Bcl-2相关X蛋白(B AX)的相对表达量。结果实验组喉鳞状细胞癌Hep-2细胞中IL-8蛋白的相对表达量明显低于NC组和空白组细胞,OD值明显低于NC组和空白组细胞(P<0.01)。实验组喉鳞状细胞癌Hep-2细胞的凋亡率明显高于空白组和NC组细胞(P<0.01)。实验组Hep-2细胞中p-AKT和抑制凋亡蛋白Bcl-2的相对表达量均低于空白组和NC组细胞,而促凋亡蛋白B AX和cleaved caspase 3的相对表达量均高于空白组和NC组细胞(P<0.05)。3组Hep-2细胞AKT蛋白的相对表达量比较,差异均无统计学意义(P>0.05)。结论IL-8可通过对磷酸肌醇3-激酶(PI3K)/AKT相关信号通路的调控,抑制喉鳞状细胞癌Hep-2细胞的增殖能力,并促进其凋亡,为喉鳞状细胞癌的诊断和治疗提供了新的靶点及可能的治疗策略。     

纤维粘连蛋白与整合素结合调控肿瘤细胞的凋亡

目的：探讨细胞表面整合素受体蛋白与纤维粘连蛋白的结合在肿瘤细胞逃避凋亡中的作用及其信号传导途径。方法：用免疫荧光法检测人鳞状上皮细胞癌HSC-3细胞中整合素受体蛋白亚单位的表达；建立细胞悬浮分离培养导致凋亡的模型；利用封闭抗体法检测不同整合素受体蛋白亚单位在此凋亡过程中的作用；Western blot检测：P53及Bcl-2／Bax在凋亡过程中表达蛋白的变化。结果：整合素受体蛋白av在正常上皮细胞中表达少或无，但在HSC-3细胞中表达较强。av封闭抗体可明显提高HSC-3细胞凋亡程度。在纤维粘连蛋白作用的HSC一3细胞中，p53蛋白表达受抑制，凋亡调节蛋白Bcl-2表达上升，Bax表达下降，Bcl-2／Bax比率上升，细胞凋亡率降低。结论：HSC-3细胞表面整合素受体蛋白av通过与纤维粘连蛋白结合，抑制了P53蛋白的表达，提高了细胞凋亡调节蛋白Bcl-2／Bax的比率，这是HSC-3细胞避免凋亡的重要原因之一。     

窖蛋白1 mRNA在人舌癌细胞系中的表达

目的:检测窖蛋白1基因mRNA在舌癌不同转移力细胞系中的表达,初步探讨窖蛋白1在肿瘤发生发展中的作用.方法:以舌鳞状细胞癌Tca8113细胞系及其脑转移株Tb作为研究肿瘤转移分子机制的模型,应用RT-PCR技术检测窖蛋白1 mRNA的表达.结果:窖蛋白1 mRNA在两种细胞中均有表达,其在Tb细胞中的表达水平高于Tca8113细胞.结论:窖蛋白1可能在舌癌转移过程中发挥作用.     

RNA干扰RhoBTB1表达促进结肠癌HT29细胞增殖、抑制其凋亡的相关研究

目的:探究RNA干扰RhoBTB1基因表达对结肠癌HT29细胞增殖、凋亡的影响。方法:采用Lipofectamine 2000将siRNA RhoBTB1或siRNA NC转入HT29细胞中，实验分为Control组、转染对照组和siRNA Rho组，噻唑蓝（MTT）和流式细胞术分别检测细胞的的活力和凋亡率，蛋白质印迹法（Western Blot）检测细胞中RhoBTB1、活化的含半胱氨酸的天冬氨酸蛋白水解酶3（Cleaved Caspase-3）、B细胞淋巴瘤/白血病-2（Bcl-2）、Bcl-2相关X蛋白(Bax)的表达量。结果:与对照组相比，HT29细胞转染siRNA RhoBTB1后，细胞中RhoBTB1蛋白的表达量显著低于对照组（P<0.05），细胞活力显著升高（P<0.05），凋亡率显著降低（P<0.05），Cleaved Caspase-3、Bax蛋白水平明显降低(P<0.05)，Bcl-2蛋白水平显著增加（P<0.05）。结论:RNA干扰RhoBTB1表达促进结肠癌HT29细胞增殖，抑制其凋亡，可能通过调节线粒体凋亡通路相关蛋白的表达量发挥作用。     

Pim-1 acts as an oncogene in human salivary gland adenoid cystic carcinoma

Background

Pim-1 (Provirus integration site for Moloney murine leukemia virus 1) belongs to the Ser/Thr kinase family and plays a pivotal role in occurrence and development of oncogenesis. Recent studies have demonstrated that Pim-1 phosphorylates RUNX3 and alters its subcellular localization. However, few studies have concerned the implications of Pim-1 in the salivary gland adenoid cystic carcinoma (ACC). In this study, we aimed to clarify the function of Pim-1 in ACC in vitro. Meanwhile, we measured the levels of Pim-1 and RUNX3 in the ACC tissues. The correlations between Pim-1/RUNX3 levels and clinical parameters were also analyzed.

Methods

SACC-83 and SACC-LM cells were transfected with the Pim-1 siRNA. Pim-1 mRNA and protein expression were measured using real-time PCR and immnuoblot, respectively. Cell proliferation was analyzed by CCK-8 assay. Cell cycle, apoptosis, and mitochondrial membrane potential were detected by flow cytometry. Effects of Pim-1 on cells’ invasion were evaluated by transwell migration assay. Pim-1 and RUNX3 levels in ACC tissues were examined by immunohistochemistry.

Results

Pim-1 siRNA reduces cell proliferation, induces apoptosis, causes cell cycle arrest through cell cycle related proteins (Cyclin D1 and CDK4), mitochondrial depolarization, and decreases invasive ability in SACC-83 and SACC-LM cells. Pim-1 and RUNX3 levels are significantly relevant and associated with T-stage and nerve invasion in the ACC tissues.

Conclusions

This study demonstrates the oncogenic role of Pim-1 in ACC. The findings also suggest that Pim-1 may serve as a neoteric therapeutic target and potential prognostic marker for ACC cancer.

     

Functional Role and Therapeutic Potential of the Pim-1 Kinase in Colon Carcinoma

Purpose

The provirus integration site for Moloney murine leukemia virus 1 (Pim-1) kinase is overexpressed in various tumors and has been linked to poor prognosis. Its role as proto-oncogene is based on several Pim-1 target proteins involved in pivotal cellular processes. Here, we explore the functional relevance of Pim-1 in colon carcinoma.

Experimental Design

RNAi-based knockdown approaches, as well as a specific small molecule inhibitor, were used to inhibit Pim-1 in colon carcinoma cells. The effects were analyzed regarding proliferation, apoptosis, sensitization toward cytostatic treatment, and overall antitumor effect in vitro and in mouse tumor models in vivo.

Results

We demonstrate antiproliferative, proapoptotic, and overall antitumor effects of Pim-1 inhibition. The sensitization to 5-fluorouracil (5-FU) treatment upon Pim-1 knockdown offers new possibilities for combinatorial treatment approaches. Importantly, this also antagonizes a 5-FU-triggered Pim-1 up-regulation, which is mediated by decreased levels of miR-15b, a microRNA we newly identify to regulate Pim-1. The analysis of the molecular effects of Pim-1 inhibition reveals a complex regulatory network, with therapeutic Pim-1 repression leading to major changes in oncogenic signal transduction with regard to p21^Cip1/WAF1, STAT3, c-jun-N-terminal kinase (JNK), c-Myc, and survivin and in the levels of apoptosis-related proteins Puma, Bax, and Bcl-xL.

Conclusions

We demonstrate that Pim-1 plays a pivotal role in several tumor-relevant signaling pathways and establish the functional relevance of Pim-1 in colon carcinoma. Our results also substantiate the RNAi-mediated Pim-1 knockdown based on polymeric polyethylenimine/small interfering RNA nanoparticles as a promising therapeutic approach.     

Aberrant expression of serine/threonine kinase Pim-3 in hepatocellular carcinoma development and its role in the proliferation of human hepatoma cell lines

Most cases of human hepatocellular carcinoma develop after persistent chronic infection with human hepatitis B virus or hepatitis C virus, and host responses are presumed to have major roles in this process. To recapitulate this process, we have developed the mouse model of hepatocellular carcinoma using hepatitis B virus surface antigen transgenic mice. To identify the genes associated with hepatocarcinogenesis in this model, we compared the gene expression patterns between pre-malignant lesions surrounded by hepatocellular carcinoma tissues and control liver tissues by using a fluorescent differential display analysis. Among the genes that were expressed differentially in the pre-malignant lesions, we focused on Pim-3, a member of a proto-oncogene Pim family, because its contribution to hepatocarcinogenesis remains unknown. Moreover, the unavailability of the nucleotide sequence of full-length human Pim-3 cDNA prompted us to clone it from the cDNA library constructed from a human hepatoma cell line, HepG2. The obtained 2,392 bp human Pim-3 cDNA encodes a predicted open reading frame consisting of 326 amino acids. Pim-3 mRNA was selectively expressed in human hepatoma cell lines, but not in normal liver tissues. Moreover, Pim-3 protein was detected in human hepatocellular carcinoma tissues and cell lines but not in normal hepatocytes. Furthermore, cell proliferation was attenuated and apoptosis was enhanced in human hepatoma cell lines by the ablation of Pim-3 gene with RNA interference. These observations suggest that aberrantly expressed Pim-3 can cause autonomous cell proliferation or prevent apoptosis in hepatoma cell lines.     

原癌基因Pim-3在胰腺癌组织中的表达及其与胰腺癌细胞增殖的相关性

目的：探讨胰腺癌组织中Pim-3的表达及其与癌细胞增殖的相关性。方法：采用免疫组化SP法检测15例正常胰腺组织和49例胰腺癌组织中Pim-3与增殖细胞核抗原(PCNA)蛋白的表达,并计算PCNA增殖指数。结果：Pim-3在正常胰腺组织中不表达,而在胰腺癌组织中阳性表达,表达率为73.47％(36/49),明显高于正常胰腺组织(P<0.01)。胰腺癌组织中PCNA的增殖指数(32.54％±14.69％)明显高于正常胰腺组织(6.25％±2.59％)(P<0.01)。且随胰腺癌细胞中Pim-3蛋白表达水平升高,肿瘤细胞增殖活性相应增加,Pim-3蛋白表达与PCNA增殖指数呈正相关(r=0.726,P<0.01)。结论：Pim-3在胰腺癌组织中高表达,Pim-3与细胞的增殖密切相关,可能在胰腺癌的发生发展中起重要作用。     

Roles of Pim-3, a novel survival kinase, in tumorigenesis

Pim-3 is a member of the Provirus integrating site Moloney murine leukemia virus (Pim) family, which belongs to the Ca(2+) /calmodulin-dependent protein kinase (CaMK) group and exhibits serine/threonine kinase activity. Similar to other members of the Pim family (i.e. Pim-1 and Pim-2), Pim-3 can prevent apoptosis and promote cell survival and protein translation, thereby enhancing cell proliferation of normal and malignant cells. Pim-3 is expressed in vital organs, such as the heart, lung, and brain. However, minimal phenotypic changes in Pim-3-deficient mice suggest that Pim-3 may be physiologically dispensable. Pim-3 expression is enhanced in several cancer tissues, particularly those of endoderm-derived organs, including the liver, pancreas, colon, and stomach. The development of hepatocellular carcinoma is accelerated in mice expressing the Pim-3 gene selectively in the liver only when these mice are treated with a hepatocarcinogen, indicating that Pim-3 can act as a promoter but not as an initiator. Moreover, inhibition of Pim-3 expression can retard in vitro cell proliferation of hepatocellular, pancreatic, and colon carcinoma cell lines by promoting cell apoptosis. Furthermore, a Pim-3 kinase inhibitor has been reported to inhibit cell proliferation in an in vivo xenograft model using a human pancreatic cancer cell line without inducing any major adverse effects. Thus, Pim-3 kinase may be a candidate molecule for the development of molecular targeting drugs against cancer.     

Identification of a phenanthrene derivative as a potent anticancer drug with Pim kinase inhibitory activity

Pim-3, a proto-oncogene with serine/threonine kinase activity, is aberrantly expressed in malignant lesions, but not in normal tissues, of endoderm-derived organs, including the pancreas, liver, colon, and stomach. Furthermore, the development of hepatocellular carcinoma is accelerated in mice expressing Pim-3 transgene selectively in the liver when these mice are treated with a hepatocarcinogen. These observations suggest that a chemical targeting Pim-3 kinase may be a novel type of anticancer drug. In the present study, we screened low molecular weight chemicals and observed that the phenanthrene derivative T26 potently inhibited Pim-3 and Pim-1, but only weakly inhibited Pim-2. Moreover, T26 markedly inhibited the in vitro growth of human pancreatic cancer cell lines by inducing apoptosis and G(2) /M arrest. The growth inhibitory effects of T26 were reversed by overexpression of Pim-3 cDNA in human pancreatic cancer cells, indicating that T26 acts primarily on Pim-3. Furthermore, T26 inhibited the growth of a human pancreatic cancer cell line in nude mice without causing apparent adverse effects when it was administered after tumor formation was evident. These observations imply that the chemical and its related compounds may be effective for the treatment of cancers in which there is aberrant Pim-3 expression.     

Detection of human papillomavirus DNA sequences in tongue squamous-cell carcinoma utilizing the polymerase chain reaction method.

Twenty-four cases of tongue squamous-cell carcinoma (SCC) were analyzed for human papillomavirus (HPV) DNAs by the polymerase chain reaction (PCR) method and the dot-blot hybridization technique. HPV DNAs were detected in 8 cases. One specimen histopathologically diagnosed as poorly differentiated grade-III SCC contained both HPV-16 and HPV-18 DNA, and 7 other cases contained HPV-16 DNA.     

pim-3基因及其相关作用

Pim-3作为表达丝氨酸和(或)苏氨酸激酶活性的原癌基因pim家族新成员,与pim-1、pim-2在序列、结构和功能上高度相似,通过磷酸化众多特异性底物而在细胞周期改变、细胞凋亡以及某些肿瘤发生中起重要调控作用.