双胰腺癌相关抗原RNA转染树突细胞诱导特异性抗癌免疫反应的实验研究

目的研究人胰腺癌MUC4与Survivin mRNA联合转染树突细胞(DC)诱导的特异性抗肿瘤免疫反应,为构建负载多抗原表位DC疫苗治疗胰腺癌提供实验依据。方法自胰腺癌患者外周血单核细胞中分离、培养DCs。使用体外转录和胰腺癌PCR技术扩增MUC4和Survivin mRNA后用电穿孔法将其联合转染DC。采用Western blot技术检测DCs中MUC4和Survivin的表达。用四甲基偶氮唑盐(MTT)法检测转染前后DCs存活率变化;使用IFN-γ酶联免疫法检测MUC4 mRNA与Survivin mRNA联合转染后DC诱导的细胞毒性T淋巴细胞(CTL)的活化反应。采用51Cr标准细胞毒实验检测转染MUC4和Survivin mRNA后DCs诱导的特异性CTL对体外胰腺癌细胞的杀伤作用。结果 MUC4与Survivin mRNA联合转染后72 h DCs中两者的相对表达量低于其分别转染。顺序转染后96 h DCs存活率降至50.2%,低于MUC4 mRNA与Survivin mRNA分别转染时DC 80%的存活率(P0.05)。MUC4和Survivin mRNA联合转染DC诱导的特异性CTL 24 h IFN-γ释放量达(33.84±3.51)U/mL,高于MUC4与Survivin mRNA分别转染DC诱导的CTL IFN-γ释放水平[(21.87±4.12)U/mL和(16.61±2.09)U/mL,P0.05]。DCs经MUC4 mRNA与Survivin mRNA联合转染后,可有效诱导HLA-A2+/MUC4+/Survivin+特异性CTL免疫反应,对体外培养的胰腺癌细胞具有显著的杀伤作用。结论 MUC4与Survivin mRNA联合转染的DCs可较单胰腺癌相关抗原负载DCs诱导出更加显著的特异性CTL抗肿瘤免疫。     

胰腺癌Capan-2细胞与树突状细胞融合诱导特异性抗癌免疫应答的体外研究

目的观察人胰腺癌Capan-2细胞与树突状细胞(DC)融合后诱导的特异性抗肿瘤免疫反应。方法收集2013年4月-2015年3月于沈阳军区总医院消化科就诊的人类白细胞抗原(HLA)-A2~+胰腺癌患者6例,从患者外周血单个核细胞中分离并培养DC。所获DC分为3组:(1)使用聚乙二醇-二甲基亚砜诱导法,将DC与Capan-2细胞融合以负载肿瘤抗原;(2)DC与Capan-2细胞共培养;(3)单独DC培养。通过流式细胞术检测PE-MUC4/FITC-CD86抗体双标细胞评估融合率;应用四甲基偶氮唑盐法检测各组DC的存活率变化。使用干扰素(IFN)γ酶联免疫法检测DC诱导的细胞毒T淋巴细胞(CTL)活化反应。采用51Cr标准细胞毒实验检测DC诱导的抗原特异性CTL对体外胰腺癌细胞的杀伤作用。多组间比较采用方差分析,进一步两两比较采用LSD-t检验。结果DC与Capan-2融合细胞同时表达DC表型(CD86)和MUC4分子,CD86与MUC4双阳性表达率为(38.30±7.30)%,明显高于共培养组(7.21±1.06)%;融合细胞组DC存活率呈时间依赖性下降,转染后96 h的存活率降低至62.81%,而与Capan-2细胞共培养组DC存活率稳定在80%以上,两组间差异有统计学意义(P0.05)。DC-Capan-2融合细胞诱导的CTL 24 h IFNγ释放量为(85.34±2.97)U/ml,DC、Capan-2共培养组DC诱导的IFNγ释放量为(19.07±4.25)U/ml,两转染组的差异有统计学意义(P0.05)。DC-Capan-2融合细胞诱导的特异性CTL能够有效识别和杀伤HLA-A2~+/MUC4~+的Capan-2细胞及HLAA2~+/MUC4-的PANC-1细胞,但不能有效识别和杀伤HLA-A2-/MUC4-的Mia Pa Ca-2细胞和HLA-A2-/MUC4~+的As PC-1细胞。结论胰腺癌细胞与DC融合后可诱导出显著的CTL抗肿瘤免疫反应,此过程受主要组织相容性复合体Ⅰ类抗原呈递的限制。     

胰腺癌Capan-2细胞总RNA转染树突细胞诱导特异性抗肿瘤免疫反应的体外研究

目的 观察人胰腺癌Capan-2细胞总RNA转染的树突细胞（DCs）所诱导的抗肿瘤免疫反应.方法 从6例胰腺癌患者外周血单核细胞中分离、培养DCs.使用电穿孔法将Capan-2细胞总RNA及MUC4 mRNA分别转染DCs.应用四甲基偶氮唑蓝（MTT）法检测转染后DCs的存活率.采用蛋白质印迹法检测DCs中MUC4 mRNA的表达.使用IFN-γ酶联免疫法检测DCs诱导的细胞毒T淋巴细胞（CTLs）的活化反应.采用51Cr标准细胞毒实验检测DCs诱导的抗原特异性CTLs对体外胰腺癌细胞的杀伤效应.结果 Capan-2细胞总RNA转染的DCs（DC-Capan-2-total RNA）的存活率呈时间依赖性下降,转染后96 h的存活率降低至60.8％,而转染MUC4 mRNA的DCs（DC-MUC4 mRNA）的存活率稳定在80.0％左右,两转染组DCs的差异具有统计学意义（P＜0.05）.DC-Capan-2-total RNA的MUC4蛋白表达量亦显著低于DC-MUC4 mRNA（P＜0.05）.DC-Capan-2-total RNA诱导的CTLs 24 h IFN-γ释放量为（89.34±3.85） U/ml,DC-MUC4 mRNA为（21.77±2.14） U/ml,两转染组的差异有统计学意义（P＜0.05）.DC-Capan-2-total RNA诱导的特异性CTLs能够有效识别和杀伤HLA-A2 ＋/MUC4＋的Capan-2细胞及HLA-A2 ＋/MUC4-的PANC1细胞,而不能有效识别和杀伤HLA-A2-/MUC4-的MiaPaCa-2细胞和HLA-A2-/MUC4＋的AsPC-1细胞.结论 胰腺癌细胞总RNA转染的DCs较单个胰腺癌相关抗原转染的DCs能诱导出更加显著的CTLs抗肿瘤免疫反应,但受到MHC Ⅰ类抗原递呈的限制.     

胰腺癌相关抗原MUC1与survivin mRNA联合转染树突细胞激发特异性细胞毒T淋巴细胞能力的体外研究

目的 研究人胰腺癌MUC1与survivin mRNA联合转染树突细胞（DC）体外激发特异性细胞毒T淋巴细胞（CTL）的能力,为构建负载多抗原表位DC疫苗治疗胰腺癌提供实验依据.方法 自6例胰腺癌患者外周血单核细胞中分离、培养并鉴定DC.常规培养人胰腺癌细胞株MiaPaCa-2,采用RT-PCR方法扩增MUC1和survivin mRNA.应用电穿孔法将两种mRNA单独或联合转染DC,分别命名为DC-MUC1、DC-survivin、DC-MUC1＋ survivin.采用实时定量PCR法检测DC的MUC1、survivin mRNA表达;四甲基偶氮唑蓝（MTT）法检测DC存活率;使用混合细胞培养法检测转染DC体外刺激自体T淋巴细胞的增殖能力;应用ELISA法检测转染DC体外激发抗原特异性CTL释放Th1型细胞因子IL-2、IL-10、granzyme B、IFN-γ的水平.结果 成功获得成熟的DC,成熟DC的表面标志物CD40、HLA-DR、CD83和CD86的阳性表达率分别为34.31％、50.21％、89.17％和73.62％.DC-MUC1的MUC1 mRNA表达量为36.24±5.17;DC-survivin的survivin mRNA表达量为34.53±4.02;DC-MUC1＋survivin的MUC1、survivin mRNA表达量分别为31.79±4.26和14.67±2.96,显著低于单转染的DC（P值均＜0.05）.DC-MUC1＋ survivin的存活率呈现时间依赖性下降,96 h时的存活率显著低于单转染DC（50.21％比80％左右,P值均＜0.05）.当作为刺激细胞的DC和作为效应细胞的T淋巴细胞比例为1∶10、1∶20时,DC-MUC1＋ survivin刺激自体T细胞的增殖指数显著高于单转染DC,差异有统计学意义（P值均＜0.05）;而比例为1∶40、1∶80时的增殖指数差异无统计学意义.当DC∶T为1∶10孵育14 d时,DC-MUC1、DC-survivin、DC-MUC1＋survivin的IL-2水平分别为（892.73±32.90）、（713.62±56.37）、（1884.37±95.21） pg/ml;granzyme B水平分别为（501.62±12.30）、（203.84±12.55）、（1193.15±86.04） pg/ml;IFN-γ水平分别为（981.50±47.82）、（696.05±41.66）、（2237.94±189.55） pg/ml.DC-MUC1＋ survivin显著高于单转染的DC,差异有统计学?     

胰腺癌细胞总RNA转染树突细胞诱导特异性CTL能力的体外研究

目的观察人胰腺癌Mia Pa Ca-2细胞总RNA电转染树突细胞(Dendritic Cell,DC)体外激发抗原特异性细胞毒T淋巴细胞(Cytotoxic T Lymphocyte,CTL)的能力。方法自6例胰腺癌患者外周血单核细胞中分离、培养DC。使用电穿孔法将Mia Pa Ca-2细胞总RNA体外转录和PCR扩增的MUC1m RNA转染DC,以未负载抗原的DC为对照。采用实时定量PCR技术检测各组DC中MUC1表达。四甲基偶氮唑盐(MTT)检测转染各组DC存活率变化;混合细胞培养法评价各组DC体外刺激自体T淋巴细胞增殖能力;ELISA法检测各组DC体外激发抗原特异性CTL细胞因子释放量。结果 Mia Pa Ca-2总RNA与MUC1 m RNA分别转染后48 h DC中目标抗原的相对表达量分别为37.24±3.17和34.53±2.02,两者比较无显著差异(P0.05)。电转染后96 h Mia Pa Ca-2总RNA转染组DC存活率降至60.81%,低于MUC1 m RNA单转染时DC的存活率(80%左右)(P0.05)。转染Mia Pa Ca-2总RNA DC刺激自体T细胞增殖指数为8 432±611.25,显著高于MUC1单独转染组3 664±305.17(P0.05);且转染Mia Pa Ca-2总RNA DC激发特异性CTL分泌IL-2、IL-10、Granzyme B、IFN-γ水平亦显著高于MUC1 m RNA单独转染组(P0.05)。结论胰腺癌肿瘤细胞总RNA转染的DC较单一胰腺癌相关抗原负载DC有更强的体外抗原特异性CTL激发能力。     

胰腺癌细胞总RNA转染树突细胞与胰腺癌-树突融合细胞激发特异性细胞毒T淋巴细胞能力的比较研究

目的比较人胰腺癌MiaPaCa-2细胞总RNA电转染树突细胞(Dendritic Cell,DC)与DCMiaPaCa-2融合细胞体外激发抗原特异性细胞毒T淋巴细胞(Cytotoxic T Lymphocyte,CTL)能力的差异。方法自6例胰腺癌患者外周血单核细胞中分离、培养DC。使用电穿孔法将MiaPaCa-2细胞总RNA转染DC,使用细胞融合方法将胰腺癌MiaPaCa-2细胞抗原负载DC,以未负载抗原的DC为对照。使用流式细胞术(FCM)检测PE-MUC/FITC-CD86抗体双标细胞评估融合效率;四甲基偶氮唑盐(MTT)检测转染各组DC存活率;混合细胞培养法评价各组DC体外刺激自体T淋巴细胞增殖能力;ELISA法检测各组DC体外激发抗原特异性CTL因子释放量。结果采用PEG-DMSO诱导的DC与MiaPaCa-2的融合细胞同时表达DC表型和MUC1分子,CD86与MUC1双阳性表达率为(42.3±7.30)%;融合细胞组DC存活率呈时间依赖性下降,转染后96h的存活率降低至62.81%,而MiaPaCa-2总RNA转染组DC细胞存活率稳定在85%左右,两组间差异有统计学意义(P0.05);转染MiaPaCa-2总RNA DC刺激自体T细胞增殖指数(DC:T=1:10)为8432±611.25,显著高于DC-MiaPaCa-2融合细胞(DC:T=1:10)5672±107.51(P0.05);且MiaPaCa-2总RNA转染DC激发特异性CTL分泌IL-12p70、IL-10和IFN-γ细胞水平亦显著异于DC-MiaPaCa-2融合细胞(P0.05)。结论胰腺癌细胞总RNA转染DC较胰腺癌-树突融合细胞有更强的体外抗原特异性CTL激发能力。     

结肠癌细胞总RNA负载成熟树突细胞体外诱导抗肿瘤作用

目的应用结肠癌细胞株SW480总RNA负载成熟树突细胞(mature dendritic cell,mDC),观察其体外诱导抗肿瘤效应。方法 GM-CSF、IL-4、TNF-α体外培养获得mDC并鉴定,电穿孔法将SW480细胞总RNA转染入mDC。流式细胞术及免疫细胞染色法检测转染后癌胚抗原(CEA)蛋白在mDC内的表达。LDH法检测负载总RNA的mDC体外诱导的特异性抗肿瘤作用。结果显微镜下观察体外培养获得的树突细胞(DC)有特征性毛刺状突起,CD83表达阳性。转染后的mDC内CEA蛋白表达阳性。特异性细胞毒实验表明,转染SW480总RNA的DC能够产生CEA特异性和肿瘤特异性的细胞毒T淋巴细胞(CTL)反应;且与转染CEA mRNA的DC相比,其能诱导出针对更多未知肿瘤抗原的抗肿瘤效应。结论负载结肠癌细胞总RNA的mDC体外能产生特异性抗肿瘤作用,为结肠癌的免疫治疗提供了理论依据。     

重组IL-12逆转录病毒转染树突细胞体外对鼻咽癌细胞的杀伤作用

目的体外实验评估重组白细胞介素(IL)-12逆转录病毒转染树突细胞对鼻咽癌细胞的杀伤作用。方法构建重组IL-12重组逆转录病毒,体外转染树突细胞(DC),经培养后收集上清液,检测IL-12、干扰素-γ(IFN)的分泌水平。以鼻咽癌细胞CNE-2为靶细胞,进行细胞毒T淋巴细胞(CTL)细胞毒活性测定。结果成功构建含有m IL-12的重组逆转录病毒;IL-12基因修饰DC可以显著诱导的大量IL-12和IFN-γ分泌,与未转染DC组比较,差异有显著意义(P0.01);DC-IL-12诱导的CTL及其上清液对鼻咽癌细胞CNE-2均有显著杀伤作用,与未转染DC组相比较差别有显著(P0.01)。结论 IL-12基因修饰树突细胞可显著诱导大量IFN-γ分泌并增强其诱导特异性CTL对肿瘤的杀伤效能。     

胰腺癌MiaPaCa-2细胞总RNA体外转染树突细胞的方法探讨

目的 探讨将胰腺癌MiaPaCa-2细胞总RNA转染树突细胞(DCs)最优化的方法.方法 以rhGM-CSF、rhIL-4和TNF-α联合诱导外周血单核细胞以获得DCs,观察DCs的形态变化,流式细胞术检测DCs表面标志CD40、HLA-DR、CD83和CD86表达,混合淋巴细胞反应(MLR)测定DCs刺激异体T细胞增殖的能力.采用脂质体转染、电穿孔及被动转染三种方法将MiaPaCa-2总RNA转染DCs,应用实时定量PCR法检测MUC1 mRNA表达,MTT法测定DCs存活率.结果 所获细胞具有典型的成熟DCs形态特征,CD40、HLA-DR、CD83和CD86阳性表达率分别为34.3%、50.2%、89.2%和73.6%,对同种异体T淋巴细胞具有极强的刺激增殖作用.电穿孔法DCs转染48 h后,DCs的MUC1 mRNA表达量为45.39±9.33,明显高于脂质体法的31.68±7.25和被动转染法的18.53±3.26;DCs存活率为(80.36±2.43)%,较被动转染法的(91.48±5.42)%略低,但高于脂质体法的(67.44±2.51)%,且基本稳定在80%左右.结论 采用电穿孔法将胰腺癌MiaPaCa-2细胞总RNA体外转染DCs的效率较高,且较安全.     

Risk factors for the development of pancreatic cancer in familial pancreatic cancer kindreds

BACKGROUND & AIMS: Approximately 10% of pancreatic cancers are inherited, but the factors that affect tumorigenesis in familial pancreatic cancer are unknown. We sought to determine whether smoking or other factors could predict cancer risk in familial pancreatic cancer kindreds. METHODS: We conducted a nested case-control study including 251 members of 28 families. All families included 2 or more members with pancreatic cancer. We determined the effects of smoking, young age of onset within the family, diabetes mellitus, sex, and number/standing of affected relatives on the risk of pancreatic cancer. RESULTS: Smoking was an independent risk factor for familial pancreatic cancer (odds ratio [OR], 3.7; 95% confidence interval [CI], 1.8-7.6), and the risk was greatest in males and subjects younger than 50 (OR, 5.2 and OR, 7.6, respectively). Smokers developed cancer 1 decade earlier than nonsmokers (59.6 vs. 69.1 years; P = 0.01), and the number of affected first-degree relatives also increased risk (OR, 1.4; 95% CI, 1.1-1.9 for each additional family member). Diabetes was not a risk factor for pancreatic cancer, although diabetes was associated with pancreatic dysplasia. One third of families demonstrated genetic anticipation, as the mean age of onset decreased by 2 decades between generations. CONCLUSIONS: Smoking is a strong risk factor in familial pancreatic cancer kindreds, particularly among males and those under age 50. Persons with multiple affected first-degree relatives are also at increased risk. These factors may be useful in selecting candidates for pancreatic cancer screening. Members of families with multiple pancreatic cancers should be counseled not to smoke.     

Risk factors for pancreatic cancer in Orientals

In order to assess what the risk factors for patients with pancreatic cancer (PC) in Taiwan are, a retrospective study was undertaken among 282 consecutively enrolled inpatients with confirmed pancreatic cancer within the past 5 years. For comparison, 282 age- and sex-matched controls were consecutively enrolled. A history of smoking, consumption of alcohol, diabetes mellitus, cholecystectomy and gastric surgery were thoroughly reviewed. Smoking and diabetes mellitus were very common among patients with pancreatic cancer compared with controls (P< 0.01). A significant linear trend towards an increased odds ratios (OR) for the development of PC with a higher level of smoking was seen (P<0.001). Diabetes mellitus (DM) also exhibited an increased risk (OR: 2.84; P<0.01), while this risk still existed among those patients who had a diabetic history of more than 3 years. Among 129 histologically established PC patients, smoking remained as a risk factor for PC, while the linear trend with an increasing OR with increasing levels of smoking was confirmed again (P<0.01). DM, particularly over the long-term, was also a risk factor for those histologically established PC patients. In summary, cigarette smoking and existing diabetes mellitus are probable risk factors for the development of pancreatic cancer in Taiwan.     

人胰腺癌胰液蛋白质谱差异表达初步分析

目的 应用蛋白质组学方法 分析胰腺癌胰液与慢性胰腺炎、胆总管结石患者胰液问差异蛋白质的表达,初步探索胰液中可能的胰腺癌标志物,为临床胰腺癌和慢性胰腺炎的鉴别诊断提供依据.方法 内镜下逆行胰胆管造影(ERCP)放置鼻胰引流管收集患者胰液,双向凝胶电泳(2-DE)分离5例胰腺癌、6例慢性胰腺炎和3例胆总管结石患者等量混合胰液的蛋白质,运用图像分析软件进行比较和分析,识别差异表达蛋白质.应用基质辅助激光解析电离飞行时间质谱(matrix-assisted laser desorption/ionization time-of-flight mass spectrometry,MALDI-TOF-MS)鉴定部分差异蛋白质点.结果 收集到胰液总量35～200 ml,Bradford法测定蛋白质浓度为0.8～4.6 μg/μl.胰腺癌、慢性胰腺炎和胆总管结石患者等量混合胰液凝胶的蛋白质点数分别为196±12、209±15和199±10,三组间两两对比后的平均匹配率均在75%以上.部分差异蛋白质点经MALDI-TOF-MS鉴定显示:相比胆总管结石和慢性胰腺炎,转甲状腺素蛋白(TTR)二聚体支链A在胰腺癌患者胰液中表达增高;载脂蛋白A1(ApoA-1)支链A、胰石蛋白支链、Reg1β再生蛋白前体表达降低.结论 人胰腺癌、慢性胰腺炎和胆总管结石患者胰液的蛋白质谱存在一定的差异,TTR、ApoA-1、胰石蛋白和Reglβ再生蛋白可能成为胰腺癌胰液中的肿瘤标志物,为临床胰腺癌和慢性胰腺炎的鉴别诊断提供依据.     

Endogenous opioids inhibit early-stage pancreatic pain in a mouse model of pancreatic cancer

BACKGROUND & AIMS: The endogenous opioid system is involved in modulating the experience of pain, the response to stress, and the action of analgesic therapies. Recent human imaging studies have shown a significant tonic modulation of visceral pain, raising the question of whether endogenous opioids tonically modulate the pain of visceral cancer. METHODS: Transgenic mice expressing the first 127 amino acids of simian virus 40 large T antigen, under the control of the rat elastase-1 promoter, that spontaneously develop pancreatic cancer were used to investigate the role of endogenous opioids in the modulation of pancreatic cancer pain. Visceral pain behaviors were assessed as degree of hunching and vocalization. RESULTS: Although mice with late-stage pancreatic cancer displayed spontaneous, morphine-reversible, visceral pain-related behaviors such as hunching and vocalization, these behaviors were absent in mice with early-stage pancreatic cancer. After systemic administration of the central nervous system (CNS)-penetrant opioid receptor antagonists naloxone or naltrexone, mice with early-stage pancreatic cancer displayed significant visceral pain-related behaviors, whereas systemic administration of the CNS-nonpenetrant opioid antagonist naloxone-methiodide did not induce an increase in visceral pain behaviors. CONCLUSIONS: Our findings suggest that a CNS opioid-dependent mechanism tonically modulates early and late-stage pancreatic cancer pain. Understanding the mechanisms that mask this pain in early stage disease and drive this pain in late-stage disease may allow improved diagnosis, treatment, and care of patients with pancreatic cancer.     

胰腺癌的早期诊断

胰腺癌恶性程度高,预后极差,目前临床早期诊断困难。回顾了胰腺癌发生、发展及转移过程中恶性分子生物学特征的变化及机制,从中分析可能用于胰腺癌临床诊断的靶点。归纳了胰腺癌的临床表现、高危因素、肿瘤标志物、联合检测及新设备在早期诊断中的作用,提出了合理联合应用血清学、影像学检查方法,研究、探寻新的肿瘤标志物均是目前提高临床胰腺癌早期诊断率的重要方法。     

Stromal response to Hedgehog signaling restrains pancreatic cancer progression

Pancreatic ductal adenocarcinoma (PDA) is the most lethal of common human malignancies, with no truly effective therapies for advanced disease. Preclinical studies have suggested a therapeutic benefit of targeting the Hedgehog (Hh) signaling pathway, which is activated throughout the course of PDA progression by expression of Hh ligands in the neoplastic epithelium and paracrine response in the stromal fibroblasts. Clinical trials to test this possibility, however, have yielded disappointing results. To further investigate the role of Hh signaling in the formation of PDA and its precursor lesion, pancreatic intraepithelial neoplasia (PanIN), we examined the effects of genetic or pharmacologic inhibition of Hh pathway activity in three distinct genetically engineered mouse models and found that Hh pathway inhibition accelerates rather than delays progression of oncogenic Kras-driven disease. Notably, pharmacologic inhibition of Hh pathway activity affected the balance between epithelial and stromal elements, suppressing stromal desmoplasia but also causing accelerated growth of the PanIN epithelium. In striking contrast, pathway activation using a small molecule agonist caused stromal hyperplasia and reduced epithelial proliferation. These results indicate that stromal response to Hh signaling is protective against PDA and that pharmacologic activation of pathway response can slow tumorigenesis. Our results provide evidence for a restraining role of stroma in PDA progression, suggesting an explanation for the failure of Hh inhibitors in clinical trials and pointing to the possibility of a novel type of therapeutic intervention.Pancreatic ductal adenocarcinoma (PDA) is the fourth most common cause of cancer-related death in the United States and is the most lethal of common human malignancies, with a 5-y survival rate of ∼7% (1, 2). The most effective chemotherapy regimens for metastatic or locally advanced inoperable disease are largely palliative and are capable of extending overall survival by only several months (3, 4). Even localized disease, treatable with surgery followed by adjuvant chemotherapy, has a dismal 5-y survival rate of 24% (1). Among gastrointestinal malignancies, PDA is unique in that it is predominantly driven by oncogenic Kras activity. In addition, PDA pathogenesis is marked by a striking desmoplastic reaction to invading tumor cells. This desmoplasia includes a dense extracellular matrix with abundant stromal fibroblasts and influences the cellular biology of the tumor as well as its response to chemotherapeutic agents.Hedgehog (Hh) signaling has been thought to play a role in PDA desmoplasia and tumor progression but is notable during embryonic development of the pancreas for its absence in the region of embryonic endoderm from which the pancreas forms (5–7). This absence of activity is required for normal specification of early pancreatic progenitor fate, and pharmacologic or antibody treatments that inhibit Hh pathway signaling cause expansion of such fates, as indicated by ectopic expression of the pancreatic progenitor marker Pdx1 (5–7). In adult mice, expression of Shh (Sonic hedgehog) is barely detectable and is limited to pancreatic duct glands, which are small outpouchings of the major pancreatic ducts (8).Increased levels of Shh expression are observed in the setting of pancreatic injury and throughout the course of human and murine PDA progression, beginning in the early epithelial precursor lesions, acinar-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia (PanIN). Shh is also expressed in locally invasive carcinomas and in distant metastases (9–11). Pharmacologic blockade of Hh pathway response with antagonists, such as cyclopamine and HhAntag, that inhibit activity of the critical Hh-transducing molecule Smoothened (Smo) has been reported to reduce the growth of human pancreatic cancer xenografts in nude mice (9, 11, 12); cyclopamine was also reported to prolong survival in a genetically engineered mouse (GEM) model of pancreatic cancer (13). Hh pathway blockade using either small-molecule antagonists or the Shh ligand-blocking antibody 5E1 was also reported to inhibit distant metastases from human pancreatic xenografts in athymic nude mice (14–16).Hh signaling in normal pancreas and in PDA is exclusively paracrine (17), with expression of Shh limited to epithelium and response restricted to stroma. Correspondingly, deletion of Smo in the pancreatic epithelium does not affect PDA pathogenesis in a GEM model (18). Hh response and its inhibition thus primarily affect stromal cells and, in the setting of PDA, has been reported to have a major impact on the desmoplastic reaction (19–21). An indirect therapeutic benefit of Hh pathway blockade thus may be to decrease stromal fibrosis and increase functional vascularity, potentially enhancing the penetration and effectiveness of standard chemotherapy (20).Given the preclinical evidence suggesting possible therapeutic benefits of Hh pathway blockade in limiting local or metastatic PDA growth and enhancement of chemotherapy, several clinical trials have been launched using small-molecule Hh pathway antagonists for this disease (22). These trials have typically combined an Hh pathway antagonist with standard chemotherapy, but, unfortunately, results have been either negative or equivocal. Thus, for example, in a phase 2 double-blind placebo-controlled study of saridegib, a cyclopamine derivative, 122 patients with previously untreated metastatic PDA were treated with either saridegib plus gemcitabine or placebo plus gemcitabine, with overall survival (OS) as a primary end point. Interim data analysis indicated that median OS for the saridegib plus gemcitabine arm was less than 6 mo whereas the median OS for the placebo plus gemcitabine arm was greater than 6 mo, resulting in termination of the clinical trial (23). In another randomized, placebo-controlled phase 2 study, the FDA-approved Smo antagonist vismodegib plus gemcitabine was compared with placebo plus gemcitabine in patients with previously untreated metastatic PDA (24). At the time of interim analysis, the OS was 6.3 versus 5.4 mo for vismodegib versus the placebo arm, with an unimpressive hazard ratio of 0.97. Recently, an interim analysis was reported of a single-arm phase 2 study using vismodegib in combination with gemcitabine and nab-paclitaxel (25), with an estimated OS of 10 mo for 59 patients, which is greater than the published historic controls of 8.5 mo for gemcitabine plus nab-paclitaxel (4).     

Remnant pancreatic volume as an indicator of poor prognosis in pancreatic cancer patients after resection

BackgroundRemnant pancreatic volume (RPV) is a well-known marker for short-term outcomes in pancreatic cancer patients after resection. However, in terms of the long-term outcomes, the significance of the RPV value remains unclear. Here, we address whether the RPV value is a predictor of the long-term outcomes in pancreatic cancer patients after resection by comparing various cancer-, patient-, and surgery-related prognostic factors and systemic inflammatory response markers in a retrospective cohort.MethodsThe RPV was measured on a three-dimensional (3D) image, revealing the actual pancreatic parenchymal remnant volume. Ninety-one patients who underwent pancreaticoduodenectomy were retrospectively enrolled. We divided the cohort into high- and low-RPV groups based on a cut-off value (>31.5 cm³, n = 66 and ≤31.5 cm³, n = 25, respectively). The median survival times (MSTs) were compared between the two groups. Using multivariate analysis, the RPV and other well-known prognostic factors were independently assessed.ResultsThe MSTs (days) were significantly different between the two groups (high, 823 vs. low, 482, p = 0.001). Multivariate analysis identified the RPV (≤31.5 cm³) (hazard ratio [HR], 2.015; p = 0.011), lymph node metastasis (HR, 8.415; p = 0.002), lack of adjuvant chemotherapy (HR, 5.352; p < 0.001), stage III/IV disease (HR, 2.352; p = 0.029), and pathological fibrosis (HR, 1.771; p = 0.031) as independent prognostic factors.ConclusionsThe present study suggests that the RPV value is also useful for predicting long-term outcomes in pancreatic cancer patients after resection.     

Surgery for pancreatic cancer: recent controversies and current practice

Pancreatic duct carcinoma remains a common disease with a poor prognosis. More than 30,000 Americans will die of the disease in 2004, making it the fourth leading cause of cancer death. Despite significant advances in the treatment of many other human tumors, the 5-year survival rate for persons diagnosed with pancreatic cancer has not changed in decades and remains <5%. This is due both to the inherently aggressive biology of the disease and to its late diagnosis in most cases. Surgical resection of localized disease remains the only hope for cure of pancreatic cancer. Over the past 2 decades, significant advances in diagnostic imaging, staging, surgical technique, and perioperative care have led to marked improvement in the surgical management of pancreatic cancer patients. Operative mortality rates for pancreaticoduodenectomy are now <5% at major centers, and the average length of hospital stay has been reduced to <2 weeks. Improvements in patient outcome after pancreatic cancer surgery have made possible, for the first time, the design and conduct of large adjuvant therapy studies in pancreatic cancer. Such clinical trials are critical for improving outcomes for pancreatic cancer patients.     

胰腺癌的不典型64排螺旋CT影像表现

目的 分析胰腺癌的64排螺旋CT的不典型表现,以提高对该肿瘤的CT征象的认识水平.方法 回顾性分析经手术病理证实的缺乏典型CT征象的12例胰腺导管腺癌的64排螺旋CT资料.结果 12例均为胰腺导管腺癌.其中,中分化导管腺癌7例,中高分化导管腺癌1例;黏液腺癌1例;腺鳞癌3例.8例导管腺癌病灶中位于胰头及(或)钩突部7例,胰颈部1例,表现为等、低密度或囊实性肿块,增强后无明显强化;5例肿瘤呈明显外生性或有外生倾向;5例肿瘤远端胰管无扩张,2例出现胆总管和肝内胆管扩张,仅1例出现肿瘤远端胰腺萎缩.1例黏液腺癌CT平扫示胰头部5 cm囊性病灶,增强后仅囊性病灶下方少许实性部分轻度强化,体尾部胰管中度扩张(7 mmn),胆总管及邻近血管未受侵犯.3例腺鳞癌病灶中位于胰头2例,胰体部1例,肿块最大径3.0～4.5 cm,CT增强扫描胰腺实质期示3例病灶内均见液化坏死区,病灶远端胰管均轻度扩张(4～5 mm),胆总管和肝内胆管均未见扩张.结论 胰腺癌可出现不典型的CT影像表现,要注意与易混淆疾病进行鉴别诊断.