内质网氧化还原蛋白基因在胰腺癌组织中的表达及其与患者预后的关系

目的:探讨内质网氧化还原蛋白(ERO1L)在胰腺癌组织中的表达及临床意义。方法:用qRT-PCR技术检测ERO1L mRNA在82例胰腺癌组织以及12例胰腺癌旁组织中的表达,分析ERO1L mRNA表达水平与胰腺癌患者临床病理因素间以及无瘤生存期和总生存期的关系。结果:胰腺癌组织中ERO1LmRNA的相对表达量明显高于癌旁组织(2.63vs.1.12,P0.01);ERO1LmRNA表达与胰腺癌患者肿瘤分化程度、远处转移、临床分期和淋巴结转移有关(均P0.05),而与性别、年龄、肿瘤大小及部位无关(均P0.05);生存分析示ERO1LmRNA高表达患者1、3年无瘤生存率和总生存率均明显低于ERO1LmRNA低表达患者(P0.01);单因素和多因素分析显示,ERO1LmRNA表达量为胰腺癌患者术后无瘤生存和总生存的独立风险因素(均P0.05)。结论:ERO1L基因在胰腺癌组织中高表达,与胰腺癌的恶性临床病理特征密切相关,为胰腺癌患者预后的独立影响因子。     

血红素氧合酶1在胰腺癌组织中的表达及临床意义

目的:探讨血红素氧合酶1(HO-1)在胰腺癌组织中的表达及临床意义。方法:分别用免疫组化法与Western blot法检测80例胰腺癌患者癌组织及癌旁组中HO-1的表达,通过统计学方法分析HO-1表达与胰腺癌患者临床病理特征及预后间的关系。结果:免疫组化与Western blot结果显示,胰腺癌组织HO-1蛋白的阳性表达率与相对表达量均明显高于癌旁胰腺组织(P0.05);HO-1在胰腺癌组织的表达与TNM分期、肿瘤分化程度及淋巴结转移明显有关(均P0.05),而与性别、年龄无明显关系(均P0.05);Log-rank检验显示,胰腺癌组织中HO-1阳性表达患者中位生存期明显低于其阴性表达患者(25.1个月vs. 36.7个月,P0.05)。结论:HO-1在胰腺癌组织呈高表达,且与胰腺癌的恶性临床特征及不良预后密切相关,可能成为胰腺癌治疗与研究的新靶点。     

维甲酸受体α和β在胰腺癌组织中的表达及意义

目的:探讨维甲酸受体-α、β在正常胰腺和胰腺癌组织中的表达及其临床意义,通过分析其表达了解维甲酸受体-α、β在胰腺癌发生发展中的作用。方法:采用免疫组织化学方法观察维甲酸受体-α、β在10例正常胰腺组织及30例胰腺癌组织中的表达情况,并分析其表达与胰腺癌临床病理特点之间的关系。结果:维甲酸受体-α在正常组织中的表达低于胰腺癌组织(P0.05),在胰腺癌组织中随临床病理分期的升高表达量增加,并且随着肿瘤组织分化程度的降低,表达量增加(P0.05),在远处转移和淋巴结转移的胰腺癌组织中的表达高于无转移组(P0.05),但与患者年龄无关(P0.05)。维甲酸受体-β在正常胰腺组织中的表达明显高于胰腺癌组织(P0.05),在胰腺癌组织中的表达与临床病理分期、肿瘤组织分化程度及年龄无关(P0.05),远处转移和淋巴结转移组中维甲酸受体-β的表达与未转移组差异亦无统计学意义(P0.05)。结论:维甲酸受体-α和维甲酸受体-β与胰腺癌发生相关;维甲酸受体-α高表达提示预后不良;维甲酸受体-β在胰腺癌中起抑癌基因的作用。     

P21ras蛋白表达在胰腺癌中的临床意义

为探讨癌蛋白p2 1ras在胰腺癌组织中的表达及其与胰腺癌的临床和病理特征的关系 ,笔者采用 p2 1ras的单克隆抗体和免疫组织化学EnVision方法分别检测石蜡包埋的 3 7例胰腺癌、17例胰腺癌远处淋巴结转移组织、5例正常胰腺组织共 5 9例标本中的p2 1ras蛋白表达情况 ,所有被检标本均经病理诊断证实。结果 :胰腺癌中 ,p2 1ras蛋白在胰腺癌中的表达率为 78.3 8% (2 9/3 7) ;胰腺癌远处淋巴结转移组织中的表达率为 47.0 6% (8/17) ;正常胰腺中未发现该蛋白表达。胰腺癌患者年龄、性别、症状、肿块大小、肿瘤部位、病理分级、临床分期和淋巴结转移各因素之间p2 1ras蛋白表达率差异无显著性 (P >0 .0 5 )。提示用免疫组织化学方法检测 p2 1ras蛋白是了解胰腺癌中K ras基因改变的非常敏感、特异的方法。该蛋白的检测有助于胰腺癌诊断。     

细胞周期调节蛋白1在胰腺癌中的表达及临床意义

目的:探讨细胞周期调节蛋白1(Spy1)在胰腺癌组织中的表达及临床意义。方法:用免疫组化法检测85例胰腺癌手术标本中Spy1蛋白的表达,用统计学方法分析Spy1表达与胰腺癌患者临床病理因素及术后生存的关系,并分析患者生存率的影响因素。结果:85例胰腺癌组织中,Spy1高表达55例(64.7%),低表达30例(35.3%)。Spy1蛋白表达与肿瘤大小、TNM分期和分化程度明显有关(均P0.05)。Spy1高表达患者1、3年无瘤生存率与总生存率均明显低于Spy1低表达患者(均P0.05)。Spy1高表达(P=0.023)及淋巴结转移(P=0.005)为胰腺癌患者术后无瘤生存率的独立危险因素,Spy1高表达(P=0.035)及TNM分期(P=0.037)为胰腺癌患者术后总生存的独立危险因素。结论:Spy1蛋白高表达与胰腺癌患者恶性临床病理因素及预后不良相关,可作为判断胰腺癌患者预后的指标。     

Survivin在胰腺癌中的表达及其与胰腺癌增殖活性的关系

目的探讨Survivin在胰腺癌中的表达及其与胰腺癌增殖活性的关系。方法用RT-PCR法检测6 2例胰腺癌、1 2例慢性胰腺炎和1 0例正常胰腺组织中Survivin mRNA的表达;用免疫组织化学法检测胰腺癌中增殖细胞核抗原(PCNA)的表达,并观察两者的关系。结果Survivin mRNA在胰腺癌中表达率为7 4.2%,在慢性胰腺炎及正常胰腺组织中不表达,前者与后两者差异有显著性(P<0.0 1);与胰腺癌的分化程度、临床分期及淋巴结转移无明显关系(P>0.0 5)。Survivin的表达与胰腺癌增殖活性有关;Survivin阳性肿瘤具有较高的增殖活性,其PCNA指数为(4 6.4±1 5.2)%,明显高于Survivin表达阴性肿瘤者(2 8.4±1 4.8)%(P<0.0 1)。结论Survivin基因在胰腺癌中过表达,并与胰腺癌的高增殖有关。提示该基因对胰腺癌的发生和发展起重要作用。Survivin基因有望成为胰腺癌诊断和治疗的新靶点。     

Ezrin在胰腺癌和胰腺囊腺瘤中的表达及其意义

目的：探讨Ezrin在正常胰腺组织、胰腺癌组织及胰腺囊腺瘤中的表达及其表达与胰腺癌侵袭转移的关系。方法：用两步免疫组织化学染色法检测13例正常胰腺, 34例胰腺癌及24例胰腺囊腺瘤组织中Ezrin的表达。结果：Ezrin在正常胰腺、胰腺囊腺瘤及胰腺癌的细胞膜强阳性表达率分别为0%, 12.5%和32.4%, 各组织中Ezrin的表达差异均有统计学意义(P＜0.05)。Ezrin表达强度与肿瘤分化程度、临床分期和有无淋巴结转移有关(P＜0.05)。结论：Ezrin在细胞膜的高表达与胰腺癌的发生及侵袭转移关系密切, Ezrin可能是影响胰腺癌患者预后及癌细胞转移的一个重要因素。     

胰腺癌中TFPI-2基因的表达及其意义

目的 探讨人胰腺癌中TFPI-2基因表达及其意义.方法 采用RT-PCR及Westernblot技术,检测TFPI-2基因在50例胰腺癌、35例转移灶、8例正常胰腺组织中的表达,同时用Boy-den小室及裸鼠皮下种植瘤模型检测胰腺癌细胞系Panc-1体内、体外侵袭及转移能力.结果 胰腺癌组织及转移灶中TFPI-2 mRNA及相应蛋白表达水平均低于正常胰腺组织(P<0.05).TFPI-2的表达水平与性别、年龄、肿瘤大小及组织学分级无关,而与临床分期、尤其是有无远处转移及神经侵犯有关.Ⅲ、Ⅳ期胰腺癌组织中TFPI-2表达水平低于Ⅰ、Ⅱ期(P<0.05);无远处转移、无神经侵犯的胰腺癌组织中TFPI-2表达水平高于有远处转移、有神经侵犯的胰腺癌组织(P<0.05).转染基因胰腺癌细胞系Pane-1-TFPI-2体外侵袭能力下降,无明显肌层浸润及肝、肺转移现象.结论 TFPI-2基因表达的降低与胰腺癌侵袭和转移有关,可能参与胰腺癌的侵袭和转移调控.     

IGF-1R在胰腺癌中的表达及其临床意义

目的：探讨胰腺癌组织中IGF-1R的表达及其临床意义。方法：应用原位杂交（DNA-RNA）技术与免疫组织化学SP法检测34例胰腺癌组织和10例正常胰腺组织中IGF-1RmRNA和IGF-1R蛋白的表达,并分析其与临床病理、预后的关系。结果：IGF-1RmRNA和IGF-1R蛋白在胰腺癌组织中阳性表达率分别为58.82%和55.88%,在正常胰腺组织中阳性表达率分别为20.00%和10.00%。两者差异均有显著性(P<0.05;P<0.01)。在胰腺癌组织中,有淋巴结转移组IGF-1R阳性表达明显强于无淋巴结转移组(P<0.05);病理Ⅲ、Ⅳ期组的IGF-1R阳性表达明显强于Ⅰ,Ⅱ期组(P<0.05)。IGF-1R表达阳性组的生存时间较阴性组明显缩短(P<0.05)。结论：IGF-1R胰腺癌组织中表达增强且与胰腺癌淋巴结转移及预后有关。     

VEGF-C，Flt4在胰腺癌中的表达及临床意义

为探讨胰腺癌组织中VEGF-C及其受体Flt4的表达并探讨其临床意义。 笔者应用免疫组织化学SP法，以VEGF-C单克隆抗体标记34例胰腺癌组织，检测其表达并分析与临床病理及预后的关系。结果示，VEGF-C在胰腺癌组织中阳性表达率61.76%，在正常胰腺组织中阳性表达率为20.00%，两者相比差异有显著性意义(P<0.01)。胰腺癌组织中，VEGF-C在有淋巴结转移组的阳性表达明显强于无淋巴结转移组(P<0.05)，其表达与Flt4蛋白表达呈正相关(P<0.05)。VEGF-C表达阳性组的生存时间较阴性组缩短。提示VEGF-C在胰腺癌组织中表达增强且与胰腺癌淋巴结转移相关。     

高糖环境下肝细胞外泌体对胰腺癌细胞迁移与侵袭能力的影响

背景与目的：在肿瘤微环境的影响和调控下,一些非肿瘤细胞通过外泌体在肿瘤的转移中起着关键作用。研究表明在胰腺癌中,高糖微环境可以促进其侵袭和转移。肝脏既是糖代谢的重要器官,也是胰腺癌转移的高发器官,胰腺癌肝转移的机制尚不清楚。因此,本研究探讨在高糖微环境下肝细胞分泌的外泌体对胰腺癌细胞侵袭、迁移的影响及机制。方法：将永生化肝细胞MIHA分别在高糖与正常糖培养基中培养后,从上清液中提取外泌体,并通过透射电镜、粒径分析和Western blot对两种培养基来源的外泌体进行鉴定;用荧光染料PKH67标记两种培养基来源的外泌体后,分别与荧光染料DAPI标记的胰腺癌细胞PANC-1共培养,通过实时激光扫描共聚焦显微镜观察PANC-1细胞对外泌体的吞噬情况。将PANC-1细胞分别与高糖培养基来源的外泌体（高糖组）及正常糖培养基来源的外泌体（正常糖组）共培养,以未加外泌体培养的PANC-1细胞为阴性对照组,随后分别用划痕试验、Transwell实验检测各组PANC-1细胞的迁移与侵袭能力,用Western blot检测各组PANC-1细胞中上皮-间充质转化（EMT）相关蛋白E-cadherin和N-c...     

吞噬和细胞运动蛋白2对胰腺癌细胞趋化性和转移能力的影响

目的观察吞噬和细胞运动蛋白2(ELMO2)对胰腺癌细胞株人源胰腺癌细胞系-1(PANC-1)的趋化运动能力、细胞黏附能力和侵袭能力的影响,探讨其作用机制。方法2018年9月至2019年7月应用小干扰RNA技术对PANC-1中ELMO2蛋白进行敲减。采用配对设计方法,分为ELMO2蛋白敲减组、阴性敲减链对照组和空白对照组。建立不同浓度的CXC趋化因子配体12(CXCL12)浓度梯度,应用趋化运动实验、细胞黏附实验和细胞侵袭实验来研究ELMO2蛋白对细胞迁移运动能力、趋化运动能力和转移侵袭能力的影响。应用免疫共沉淀技术对ELMO2蛋白与G蛋白阿尔法亚基i2蛋白(Gαi2)的相互作用机制进行研究。组间比较采用双因素方差分析方法。结果将RNAi干扰链转染进入PANC-1细胞株,细胞中ELMO2蛋白表达量明显降低。在趋化因子浓度为10μg/L时,实验结果显示,敲减组定向跨膜的移动细胞数量明显低于阴性对照组[(36.67±1.21)个比(75.67±1.76)个,t=18.270,P<0.01],差异有统计学意义。在趋化因子浓度为10μg/L的条件下,实验结果显示,敲减组细胞黏附率明显低于阴性对照组[(0.47±0.02)%比(0.79±0.01)%,t=19.850,P<0.01],差异有统计学意义。趋化因子CXCL12浓度为10μg/L时,实验结果显示,敲减组穿越基质胶的细胞数量明显低于阴性对照组,侵袭能力明显减弱[(84.33±2.03)个比(132.00±0.58)个,t=22.610,P<0.01],差异有统计学意义。构建吞噬与细胞运动蛋白2的过表达质粒(代号质粒362)载体,在Flag标签蛋白抗体的免疫沉淀物中发现Gαi2蛋白的条带。结论ELMO2蛋白的敲减可以减弱胰腺癌细胞的趋化运动能力、黏附能力和侵袭能力。外源性免疫共沉淀试验结果表明,ELMO2蛋白与Gαi2蛋白存在直接相互作用关系。     

TAp63在胰腺癌中的表达及意义

目的:探讨TAp63在胰腺癌中的表达及其意义。方法:分别real-time PCR和Western blot检测TAp63 m RNA与蛋白在21例胰腺癌及其配对癌旁组织、3种胰腺癌细胞(PANC-1、CFPAC-1、Bx PC3)及正常胰腺细胞(HPDE6-C7)中的表达;用TAp63-si RNA转染PANC-1细胞后,观察TAp63 m RNA与蛋白表达的变化,并用MTT和Brd U法检测转染后PANC-1细胞的增值情况。结果:胰腺癌组织中TAp63 m RNA表达量明显低于癌旁正常胰腺组织(t=2.572,P=0.0158);TAp63m RNA与蛋白在3种胰腺癌细胞株中的表达量均明显低于正常胰腺HPDE6-C7细胞(均P0.05)。与未处理的PANC-1细胞比较,转染TAp63-si RNA后的PANC-1细胞TAp63 m RNA与蛋白明显降低,但细胞增殖与DNA合成能力均明显增强(均P0.05)。结论:TAp63在胰腺癌组织与细胞中表达降低,且表达量越低,细胞生长能力越强。     

Adenovirus-mediated wild-typep53 tumor suppressor gene therapy induces apoptosis and suppresses growth of human pancreatic cancer

Background: Thep53 tumor suppressor gene is mutated in up to 70% of pancreatic adenocarcinomas. We determined the effect of reintroduction of the wild-typep53 gene on proliferation and apoptosis in human pancreatic cancer cells using an adenoviral vector containing the wild-typep53 tumor suppressor gene. Methods: Transduction efficiencies of six p53-mutant pancreatic cancer cell lines (AsPC-1, BxPC-3, Capan-1, CFPAC-1, MIA PaCa-2, and PANC-1) were determined using the reporter gene construct Ad5/CMV/-gal. Cell proliferation was monitored using a³H-thymidine incorporation assay, Western blot analysis forp53 expression was performed, and DNA laddering and fluorescence-activated cell sorter analysis were used to assess apoptosis.p53 gene therapy was tested in vivo in a subcutaneous tumor model. Results: The cell lines varied in transduction efficiency. The MIA PaCa-2 cells had the highest transduction efficiency, with 65% of pancreatic tumor cells staining positive for beta-galactosidase (-gal) at a multiplicity of infection (MOI) of 50. At the same MOI, only 15% of the CFPAC-1 cells expressed the -gal gene. Adenovirus-mediatedp53 gene transfer suppressed growth of all human pancreatic cancer cell lines in a dose-dependent manner. Western blot analysis confirmed the presence of the p53 protein product at 48 hours after infection. DNA ladders demonstrated increased chromatin degradation, and fluorescence-activated cell sorter analysis demonstrated a four-fold increase in apoptotic cells at 48 and 72 hours following infection with Ad5/CMV/p53 in the MIA PaCa-2 and PANC-1 cells. Suppression of tumor growth mediated by induction of apoptosis was observed in vivo in an established nude mouse subcutaneous tumor model following intratumoral injections of Ad5/CMV/p53. Conclusions: Introduction of the wild-typep53 gene using an adenoviral vector in pancreatic cancer withp53 mutations induces apoptosis and inhibits cell growth. These data provide preliminary support for adenoviral mediatedp53 tumor suppressor gene therapy of human pancreatic cancer.Presented at the 51st Annual Cancer Symposium of The Society of Surgical Oncology, San Diego, California, March 26–29, 1998.     

TIMP-1 overexpression in pancreatic cancer attenuates tumor growth, decreases implantation and metastasis, and inhibits angiogenesis.

BACKGROUND: Matrix metalloproteinases (MMPs) are involved in pancreatic cancer progression. This study was undertaken to determine the effects of overexpression of a natural tissue inhibitor of MMP (TIMP-1) on pancreatic cancer cell growth, metastasis, and angiogenesis. METHODS: A poorly differentiated human pancreatic cancer cell line (PANC-1) underwent gene transfection to overexpress TIMP-1 (CD-1 cells). One million PANC-1 or CD-1 cells were injected into 40 nude mice subcutaneously (N = 20) or orthotopically (N = 20). Mice were sacrificed at 120 days. TIMP-1 overexpression by CD-1 cells was confirmed prior to injection and after necropsy. Immunohistochemical staining was undertaken after necropsy to evaluate tumors for TIMP-1, MMP-2, apoptosis (TUNEL), and angiogenesis (CD-31). RESULTS: Tumors of CD-1 cells were less likely to implant (35% vs 70%, P = 0.05) and grew to smaller size (0.5 g +/- 0.03 vs 1.5 g +/- 0.20, P < 0.001) than tumors of PANC-1 cells. As well, subcutaneous CD-1 tumors appeared later than PANC-1 tumors (45 days +/- 2.0 vs 27 days +/- 2.2, P < 0.001). Orthotopic CD-1 tumors metastasized less often than PANC-1 tumors (20% vs 60%, P < 0.05). MMP-2 expression was similar in PANC-1 and CD-1 tumors, while CD-1 tumors showed increased TIMP-1 expression, increased apoptosis, and decreased angiogenesis relative to PANC-1 tumors. CONCLUSIONS: TIMP-1 overexpression reduces pancreatic cancer cell implantation, growth, metastasis, and angiogenesis, while increasing tumor apoptosis, all without altering MMP-2 production. This study demonstrates the potential role of TIMP-1 as a target in gene therapy for pancreatic cancer.     

亚硒酸钠诱导胰腺癌PANC-1细胞凋亡

目的 探讨亚硒酸钠( Na2SeO3)对胰腺癌细胞系PANC-1生长的影响及其作用机制.方法 以PBS为对照,用2、5、10、20μmol/L Na2SeO3处理胰腺癌PANC-1细胞株,用四甲基偶氮唑盐(MTT )比色法检测细胞活性,流式细胞仪检测细胞凋亡情况,观察Na2SeO3对PCNA-1细胞株生长的影响;通过ELISA法检测Caspase-3蛋白含量,Western blotting法检测细胞内及线粒体内细胞色素C( cytochrome C,Cyt C)含量.结果 与时照组相比,用不同浓度Na2SeO3作用24 h、48 h后,对PANC-1细胞抑制作用有明显差异(P<0.05);呈浓度时间依赖性.与PBS对照组相比,Na2SeO3作用组Caspase-3含量明显升高(P<0.01),细胞色素C从线粒体向胞质释放明显增多,但蛋白含量无明显变化.结论 Na2SeO3抑制PANC-1细胞的生长,促进细胞凋亡,其机制可能与Caspase-3的激活及细胞色素C的释放有关.     

TPM4对人胰腺癌细胞侵袭和迁移的影响

目的 探讨原肌球蛋白4（TPM4）对人胰腺癌细胞侵袭和迁移的影响。方法 采用qRT-PCR检测人正常胰腺导管上皮细胞（HPDE）和人胰腺癌细胞系（ASPC-1、BXPC-3、MIA PaCa-2、PANC-1、SW1990）中TPM4 RNA表达量。采用siRNA或过表达慢病毒感染胰腺癌细胞（MIA PaCa-2、PANC-1）,通过qRT-PCR、Western blotting检测各组细胞TPM4的表达,划痕实验及Transwell实验检测各组胰腺癌细胞侵袭和迁移能力。结果 GEPIA数据库中胰腺癌组织TPM4表达明显高于正常胰腺组织（P<0.05）,qRT-PCR分析TPM4 RNA在胰腺癌细胞系中表达均高于HPDE（P<0.0001）。与对照组相比,在MIA Paca-2和PANC-1中过表达TPM4促进了胰腺癌细胞侵袭迁移能力（均P<0.01）,而敲低TPM4胰腺癌细胞侵袭迁移能力则明显减弱（均P<0.01）。结论 TPM4在胰腺癌细胞中呈现高水平表达,可能在胰腺癌中发挥着癌基因的作用,其并可促进胰腺癌细胞迁移及侵袭能力。     

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.     

The cytotoxic effects of bile acids in crude bile on human pancreatic cancer cell lines

Pancreatic cancer frequently causes extrahepatic cholestasis. To identify the direct effects of bile acids in jaundiced serum on pancreatic cancer, the proliferation of PANC-1 and MIA PaCa-2 cells as well as the ultrastructural alteration of PANC-1 cells cultured in crude bile modified media were studied. The growth of these cells in the RPMI-1640 media with or without 1%, 2%, and 4% of the refined crude bile was assessed after 48 and 96 h of incubation. The ultrastructure of PANC-1 cells was investigated by scanning and transmission electron microscopy after 24 and 48 h of incubation. The proliferation of both cell lines in the bile-treated media was greatly inhibited. The inhibitory rates of bile on PANC-1 ranged from 24.1% ± 3.3% to 66.9% ± 6.6% (P < 0.01) and those on MIA PaCa-2 ranged from 16.7% ± 3.8% to 50.7% ± 5.5%. (P < 0.01). When the bile-added media were replaced, the cells were able to restore their proliferating ability. The PANC-1 cells incubated in the bile-supplied media indicated that the mirovilli, mitochondria, and other organelles had thus been injured. These results suggest that bile acids appear to inhibit the proliferation of PANC-1 and MIA PaCa-2 cells, and the probable inhibitory mechanism is mainly considered to be due to the cytotoxicity of such bile acids. Received: November 2, 1999 / Accepted: May 30, 2000     

Increased PDX-1 expression is associated with outcome in patients with pancreatic cancer

BACKGROUND: During pancreatic development, pancreatic duodenal homeobox gene-1 (PDX-1) is expressed in pancreatic duct cells that have the potential to differentiate into islets. Therefore, PDX-1 is thought to be a marker of de-differentiated cells with the capacity to redifferentiate into several pancreatic cell types. We analyzed PDX-1 expression in human pancreatic cancer specimens, pancreatic cancer cell lines, and the effects of forced expression of PDX-1 in pancreatic cancer cells. METHODS: Thirty-five pancreatic adenocarcinomas were immunohistochemically stained with a polyclonal rabbit antibody against mouse PDX-1. Correlations with tumor characteristics were made with chi-squared analysis. The influence of clinicopathologic factors on survival was assessed. The expression of PDX-1 in pancreatic cancer cells was examined. Replication-deficient recombinant adenoviruses were constructed by the cosmid-adenoviral DNA terminal protein complex method. PANC-1 cells were infected with Ad-pdx-1 or Ad-LacZ. PANC-1 cells that were infected with adenovirus were used in a cell growth assay and a migration assay and for morphologic analysis. RESULTS: Interestingly, 43% of pancreatic cancers were positive for PDX-1 expression, and 57% of pancreatic cancers were negative (normal pancreatic exocrine tissue shows little or no staining for PDX-1). Lymph node metastasis (P =.02) and histologic grade (P =.04) were correlated significantly with PDX-1 expression. Patients with positive PDX-1 had a significantly worse prognosis than those patients with negative PDX-1 (P =.02). Importantly, PDX-1 was an independent variable that effected overall survival (P =.03). Pancreatic cancer cell lines showed no PDX-1 expression. There were no significant differences in cell proliferation or morphologic condition between Ad-pdx-1- and Ad-lacZ-infected PANC-1 cells. However, Ad-pdx-1-infected PANC-1 cells did show a significantly higher migration rate than Ad-lacZ-infected PANC-1 cells. CONCLUSIONS: Re-expression of PDX-1 may represent a return to a more de-differentiated state by more aggressive pancreatic cancers and may also represent an important new tumor marker for these aggressive cancers.