吉西他滨对胰腺癌细胞株PANC-1中TMS1/ASC基因表达及启动子甲基化的影响

目的:观察吉西他滨(GEM)对胰腺癌细胞株PANC-1中甲基化诱导静止基因(TMS1/ASC)的表达及其启动子区甲基化的影响,并讨论其疗效机制。方法:将对数生长期PANC-1分为两组,以加入4.27μg/ml的GEM作用于PANC-1细胞者为实验组(GEM组),以不加GEM者为对照组,分别继续培养24h,采用DNA原位末端标记(TUNEL)法结合激光共聚焦显微镜观察两组PANC-1细胞凋亡和细胞核形态变化;采用RT-PCR检测两组PANC-1细胞中TMS1/ASC mRNA的表达情况;采用重亚硫酸盐限制内切酶法(COBRA)检测两组PANC-1细胞中TMS1/ASC的甲基化状态。结果:(1)GEM组中PANC-1凋亡明显(FITC和PI双染阳性),对照组未见PANC-1凋亡;(2)GEM组PANC-1的TMS1/ASC mRNA表达显著高于对照组(P<0.01);(3)GEM组PANC-1中TMS1/ASC启动子区甲基化率显著低于对照组(P<0.01)。结论:GEM可能通过促进PANC-1细胞凋亡,上调TMS1/ASC mRNA表达以及抑制TMS1/ASC启动子区的甲基化而起到治疗胰腺癌的作用。     

Low-dose gemcitabine induces major histocompatibility complex class I-related chain A/B expression and enhances an antitumor innate immune response in pancreatic cancer

We investigated the effect of gemcitabine (GEM), a key drug for pancreatic cancer treatment, on the expression of cell surface MICA/B in pancreatic cancer cells and resulting cytotoxicity of γδ T cells. We assessed the effect of GEM on the upregulation of cell surface MICA/B expression by flow cytometry, utilizing six pancreatic cancer cell lines. MICA and CD16 expressions from resected pancreatic cancer patient specimens, which received neoadjuvant chemotherapy (NAC) with GEM, were analyzed by immunohistochemistry. GEM could increase MICA/B expression on cell surface in pancreatic cancer cell lines (in 2 of 6 cell lines). This effect was most effectively at concentration not affecting cell growth of GEM (0.001 μM), because MICA/B negative population was appeared at concentration at cytostatic and cytotoxic effect to cell growth (0.1 and 10 μM). The cytotoxic activity of γδ T cells against PANC-1 was detected and functions through interactions between NKG2D and MICA/B. However, the enhancement of NKG2D-dependent cytotoxicity with increased MICA/B expression, by GEM treatment, was not observed. In addition, soluble MIC molecules were released from pancreatic cancer cell lines in culture supernatant with GEM treatment. Immunohistochemical staining demonstrated that MICA expression in tumor cells and CD16 positive cells surrounding tumors were significantly higher in the NAC group compared to that of the control group. There was a significant correlation between NAC and MICA expression, as well as NAC and CD16 positive cell expression. The present results indicate that low-dose GEM-induced MICA/B expression enhances innate immune function rather than cytotoxicity in pancreatic cancer. In addition, our result suggests that the inhibition of cleavage and release of MIC molecules from the tumor surface could potentially improve NKG2D-dependent cytotoxicity.     

非小细胞肺癌中S100A2、S100A4及S100P表达及意义

目的研究钙结合蛋白S100家族中S100A2、S100A4及S100P基因在非小细胞肺癌(non-small cell lung cancer,NSCLC)中的表达,阐明其与肺癌发生及转移的关系。方法以12例正常肺组织为对照,采用半定量RT-PCR技术检测17例腺癌和12例鳞癌及其癌旁组织中S100A2、S100A4及S100P mRNA的表达水平。结果(1)S100A2、S100A4及S100P mRNA在NSCLC中的表达量均高于癌旁和正常组织。(2)肺腺癌中三者mRNA表达量均高于癌旁和正常组织;肺鳞癌中S100A4和S100P mRNA的表达量高于正常组织。(3)根据不同的临床分期,S100A2、S100A4 mRNA在Ⅱ期与Ⅲ期中的表达量均高于Ⅰ期;S100P mRNA在Ⅲ期中的表达量高于Ⅰ期。(4)根据有无淋巴结转移,三者mRNA在有淋巴结转移癌组织中的表达量均高于无淋巴结转移的癌组织。(5)根据有无静脉癌栓,S100A4 mRNA在有静脉癌栓的癌组织中的表达量高于无静脉癌栓的癌组织。结论S100A4、S100A6、S100P在NSCLC中表达增加,尤其是在有淋巴结转移及TMN分期越高的癌组织中表...     

螺旋CT结合CA19-9在胰腺癌可切除性评价中的应用

目的 探索螺旋CT双期扫描与CA19-9检测相结合在胰腺癌术前可切除性评价中的应用价值. 方法 回顾分析2002年2月至2006年2月本院52例胰腺癌患者的临床资料,根据螺旋CT双期扫描结果和血清CA19-9检测结果进行胰腺癌术前可切除性评价. 结果 CT判断胰腺癌不可切除的准确率为100%,而判断可切除的准确率为73.30%.随着胰腺癌浸润程度的进展,CA19-9水平有增高的趋势.局部侵犯组CA19-9均值与可切除组和转移组CA19-9均值差异无统计学意义.以CA19-9大于150 U/ml作为不可切除判断的临界值,在不可切除组41例患者中,只有10例患者的血清CA19-9水平大于150 U/ml,占24.39%. 结论 血清CA19-9水平随胰腺癌浸润进展程度有逐渐升高的趋势,但CA19-9水平并不能反应胰周大血管受侵犯.CA19-9检测与CT结合在胰腺癌术前可切除性评价中的临床实用价值有限.     

miR-142-5p 靶向 MCL-1 对胆管癌细胞上皮-间质转化及吉西他滨 化疗敏感性的影响

目的 探讨 miR-142-5p 靶向髓细胞白血病因子 1 (myeloid cell leukemin-1, MCL-1) 对人胆管癌 细胞 QBC939 上皮间质化 (epithelial-mesenchymal transition, EMT) 及吉西他滨 (Gemcitabine, GEM) 化疗 敏感性的影响。 方法 体外培养胆管癌细胞 QBC939 及人正常胆管上皮细胞 HIBEC, 随机分为对照组、 miR-142-5p 阴性对照 (NC) 组和 miR-142-5p 模拟物 (mimics) 组。 实时荧光定量 PCR (RT-qPCR) 法检 测各组 QBC939 细胞和 HIBEC 细胞中 miR-142-5p 和 MCL-1 mRNA 表达情况; 划痕实验和 Transwell 实验分别 检测各组 QBC939 细胞迁移和侵袭变化情况; 蛋白印迹分析法检测各组 QBC939 细胞上皮型钙黏蛋白 (E-cadherin)、 神经性钙黏附蛋白 (N-cadherin) 和波形蛋白 (Vimentin) 表达变化; 双荧光素酶报告实验验证 miR-142-5p 与 MCL-1 的靶向关系; 使用浓度为 0. 625 μg / mL GEM 处理转染 miR-142-5p 后的 QBC939 细胞, 同时设置对照组, MTT 检测细胞增殖, Annexin V-FITC/ PI 试剂盒检测细胞凋亡。 结果 与人正常胆管细胞 HIBEC 相比, 胆管癌细胞 QBC939 中 miR-142-5p 呈低表达, MCL-1 mRNA 呈高表达。 经 Targetscan Human 数据库预测显示, miR-142-5p 与 MCL-1 mRNA 3′UTR 区有结合位点。 与 MCL-1-3′UTR-WT + miR-142-5p NC 组比较, MCL-1-3′UTR-WT + miR-142-5p mimics 组荧光素酶活性降低 (P< 0. 05)。 与对照组和 miR-142-5p NC 组相比, miR-142-5p mimics 组 QBC939 细胞 miR-142-5p 表达水平、 E-cadherin 蛋白表达水平显著升高 (P< 0. 05), MCL-1 mRNA 和蛋白表达、 N-cadherin、 Vimentin 蛋白表达水平显著降低 (P< 0. 05), 细胞迁 移、 侵袭能力显著减弱 (P< 0. 05); 与 miR-142-5p NC + GEM 组相比, miR-142-5p mimics + GEM 组 QBC939 细胞存活率显著降低, 凋亡率增加 (P< 0. 05)。 结论 过表达 miR-142-5p 可通过靶向抑制 MCL-1 表达从而 抑制人胆管癌细胞的 EMT、 增加胆管癌细胞对 GEM 的化疗敏感性。     

Transient silencing of galectin-3 expression promotes both in vitro and in vivo drug-induced apoptosis of human pancreatic carcinoma cells

Pancreatic cancer demonstrates a strong resistance to anticancer drugs, presumably due to its resistance to drug induced apoptosis. Although gemcitabine (GEM) might be partially effective for treating advanced pancreatic cancer, its efficacy is still less than satisfactory. Galectin-3 (gal-3), a member of the β-galactoside-binding protein family, is a multifunctional protein with roles in tumor cell adhesion, proliferation, differentiation, angiogenesis, metastasis, and apoptosis. We have utilized gal-3 small interfering RNA (siRNA) to probe whether gal-3 regulates anticancer drug-induced apoptosis in pancreatic cancer cells. We found that Gal-3 siRNA augmented GEM- and cisplatin-induced apoptosis in pancreatic cancer cell lines in vitro. Mitochondrial depolarization induction was increased in gal-3-silenced cells after GEM treatment, resulting in activation of caspase-9, but not caspase-8. Akt phosphorylation was significantly downregulated in gal-3- silenced cells in association with apoptosis. Moreover, intratumoral administration of gal-3 siRNA increased the GEM sensitivity of tumor xenografts produced by subcutaneous inoculation of pancreatic cancer cells into nude mice. These results suggest that gal-3 might provide a novel therapeutic target in pancreatic cancer.     

The role of endoscopic ultrasound and endoscopic ultrasound-guided fine-needle aspiration in distinguishing pancreatic cystic lesions

Distinguishing mucinous from nonmucinous cystic lesions of the pancreas often constitutes a diagnostic dilemma. The clinical management differs between such lesions; therefore it is important to make an accurate preoperative diagnosis. Various centers have reported conflicting results regarding their ability to detect mucin-producing neoplastic cells and appropriately reach a diagnosis based on endoscopic ultrasound (EUS) guided FNA. The aim of this study is to assess the ability of EUS-FNA cytology to diagnose and differentiate mucinous from nonmucinous pancreatic cystic lesions. We reviewed records of patients who underwent EUS of pancreatic cystic lesions. If FNA was performed and mucinous neoplasm was suspected, aspirate was evaluated for cytomorphology and presence of mucin. FNA results were compared to final histologic diagnosis if surgery was performed.Cytologic diagnosis was provided for 28/30 (93%). By comparing EUS-FNA diagnoses with final surgical pathology, FNA accurately diagnosed in 10/11 cases with sensitivity and specificity for detection of malignancy of 100 and 89, respectively, while the accuracy for identification of mucinous cystic neoplasms was 100%. Our results indicate that in the appropriate clinical and imaging setting, EUS-FNA cytology with analysis for mucin production by tumor cells is an important test in distinguishing pancreatic cystic lesions and guiding further management.     

siRNA干扰沉默S100A4基因表达对喉癌Hep2细胞周期和侵袭的影响

目的应用RNA干扰技术下调喉癌Hep2细胞中S100A4基因的表达,探讨其对Hep2细胞周期和细胞侵袭力的影响。方法脂质体法转染S100A4siRNA至Hep2细胞。Real-time PCR和Western blot验证S100A4基因mRNA和蛋白水平的表达,流式细胞术和transwell实验分别检测下调S100A4表达对Hep2细胞周期和侵袭能力的影响。结果 S100A4 mRNA和蛋白表达水平明显降低,细胞增殖指数显著降低,并且处于G1期细胞数明显增多,细胞侵袭能力显著降低。结论 S100A4siRNA转染喉癌Hep2细胞能有效下调S100A4基因的表达,从而影响Hep2的细胞周期和抑制细胞的侵袭能力。     

Antimetastatic efficacy of adjuvant gemcitabine in a pancreatic cancer orthotopic model

Gemcitabine is a promising new agent that has been recently studied for palliation of advanced (stage IV) unresectable pancreatic cancer. We hypothesized that adjuvant gemcitabine would reduce recurrence and metastases following surgical resection of pancreatic cancer. To test this hypothesis, we evaluated gemcitabine on a green fluorescent protein (GFP) transductant of the human pancreatic cancer cell line BxPC-3 (BxPC-3-GFP) using surgical orthotopic implantation (SOI) in nude mice. GFP enabled high resolution fluorescent visualization of primary and metastatic growth. Five weeks after SOI, the mice were randomized into three groups: Group I received exploratory laparotomy only. Group II underwent surgical resection of the pancreatic tumor without further treatment. Group III underwent tumor resection followed by adjuvant treatment with gemcitabine, 100 mg/kg every three days for a total of four doses, starting two days after resection. The mice were sacrificed at thirteen weeks following implantation and the presence and location of recurrent tumor was recorded. Gemcitabine reduced the recurrence rate to 28.6% compared to 70.6% with resection only (P=0.02) and reduced metastatic events 58% in the adjuvant group compared to resection only. This study, demonstrating that gemcitabine is effective as adjuvant chemotherapy post-pancreatectomy, suggests this new indication of the drug clinically. This revised version was published online in July 2006 with corrections to the Cover Date.     

miR-125b-1增强乳腺癌SKBR-3细胞对紫杉醇的药物敏感性

目的探讨miR-125b-1增强紫杉醇对乳腺癌SKBR-3细胞化疗敏感性的影响,及其对靶基因Her2蛋白表达的影响。方法合成miR-125b-1并通过LipofectamineTM2000转染SKBR-3细胞,将实验分为空白对照组（脂质体转染SKBR-3细胞株）、阴性对照组（siRNA转染SKBR-3细胞株）、miR-125b-1组（miR-125-1转染SKBR-3细胞株）3组。分别用RT-PCR和蛋白质印迹法检测Her2 mRNA和蛋白质表达水平的变化;流式细胞仪检测细胞周期;MTT法检测miR-125b-1对紫杉醇作用于SKBR-3细胞化疗敏感性的影响。结果 miR-125b-1转染后的SKBR-3细胞中Her2 mRNA和蛋白质水平显著下降;流式细胞仪检测结果显示,转染miRNA-125b-1的SKBR-3细胞G2M期细胞比例显著高于其他组（P=0.000）,而空白对照组与阴性对照组比较差异无统计学意义（P=0.094）。三组之间比较,G0-G1期、S期比例差异无统计学意义;用miR-125b-1处理组细胞的IC50与未处理组相比下降2.69倍,差异有统计学意义（P〈0.05）。结论 miR-125b-1可增强乳腺癌SKBR-3细胞对紫杉醇的化疗敏感性,下调Her2可能是其作用机制之一。     

Evaluation of performance of EUS-FNA in preoperative lymph node staging of cancers of esophagus, lung, and pancreas

We reviewed the cytologic and histologic diagnoses and EUS report of 77 consecutive patients who had undergone EUS-FNA preoperative staging for esophageal, lung, and pancreatic cancers at our institution. A total of 122 EUS-FNA lymph nodes were identified. Thirty of 77 cases had histologic follow-up. Using surgical node staging and/or surgical resection as the reference standard, the sensitivity, specificity, accuracy, and positive and negative predictive values were 75%, 95%, 89%, 86%, and 90%, respectively, for EUS-FNA node staging. We compared cytologically malignant and benign lymph node groups with eight EUS parameters including the total number of lymph nodes found by EUS, the shape, margin, long axis, short axis, echogenicity, location of the lymph node, and EUS tumor staging. We found that the short axis is the best EUS feature to predict malignancy. Lymph nodes found in an abdominal location in esophageal and lung cancer are likely malignant.     

New infusion device for trans-tissue, sustained local delivery of anticancer agent to surgically resected tissue: potential use for suppression of local recurrence of pancreatic cancer

Local recurrence is a major cause of death of patients who have undergone resection for pancreatic cancer. To reduce the incidence of local recurrence, a new drug-infusion device, which is fixed on resected tissues immediately after surgery, was devised for trans-tissue, sustained local delivery. The drug-infusion device proposed here has the following functions: tight adhesion of the device on resected tissues, sustained drug infusion to the tissue, drug reloading, and easy removal from the body after use. The fabricated prototype experimental device, described here, was a thin infusion pouch made of a thin elastomer film (segmented polyurethane), which is connected to an elastomeric tube for drug reloading. The suppressive effect of the device delivering the anticancer agent, gemcitabine (GEM), was examined using subcutaneous tumor-bearing athymic mouse. A low-dose, local sustained GEM delivery using the device significantly suppressed the tumor growth and regrowth after surgery. The preliminary model experimental result appears to provide a promising therapeutic procedure for increased survival rate of the patients undergoing surgery for pancreatic cancer.     

Impact of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in lymph nodal and mediastinal lesions: a multicenter experience

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an established procedure in lung cancer (LC) staging and in the diagnosis of mediastinal masses. Most of the experiences reported refer to single specialized centers where dedicated teams of endoscopists and pathologists perform the procedure. We report the EUS-FNA experience of a cooperation group involving clinicians and cytopathologists from three hospitals. Fifty-seven consecutive EUS-FNA of mediastinal nodes in LC patients, eight mediastinal and two subdiaphragmatic masses were collected in 3 years. EUS-FNA was performed by two endoscopists and three experienced pathologists. On-site evaluation was performed in all cases by the three cytopathologists. Lymph node negative cases underwent surgery, which confirmed the cytological diagnoses but also detected two false negatives. Four of the 10 EUS cytological diagnoses of mediastinal and subdiaphragmatic masses were histologically confirmed. All EUS diagnoses were blindly reviewed by three pathologists to assess intra and interpersonal reproducibility. FNA-EUS diagnoses were: 10 inadequate (17%), 10 negative (17%), 4 suspicious (7%) and 33 positive (59%). Diagnoses of mediastinal and subdiaphragmatic masses were: relapse of lung carcinoma (3), mesenchimal tumor not otherwise specifiable (3), gastrointestinal stromal tumor (GIST) (1), esophageal carcinoma (2) and paraganglioma (1). The sensitivity attained was 85% and the specificity 100%; revision of the slides demonstrated a significant diagnostic reproducibility of the three cytopathologists (P < 0.5). The sensitivity and specificity attained were similar to those reported in the literature suggesting that experienced cytopathologists and endoscopists from different institutions can employ the same procedure reaching comparable results.     

Hedgehog pathway expression in heterogeneous pancreatic adenocarcinoma: implications for the molecular analysis of clinically available biopsies.

Recent studies suggest that hedgehog (HH)-pathway signaling is required for the initiation and continued growth of pancreatic adenocarcinoma (PAC). Definitive gene expression analysis of PAC remains difficult, owing to the host desmoplastic stromal interaction and subsequent tumor heterogeneity. The primary goal of this study was to evaluate the effect of heterogeneity within a series (n=5) of matched clinical PAC biopsies [snap-frozen, formalin-fixed paraffin-embedded (FPE), endoscopic ultrasound-guided fine-needle aspirate (EUS-FNA)]. Differential expressions, specific to tumor cells, were evaluated by comparisons of uninvolved pancreas (n=9), EUS-FNA (n=14), and macrodissected (tumor-cell-enriched) biopsies (n=16). To determine whether treatment modulates gene expression, a unique (independent) set of synchronous EUS-FNA samples (n=4) was obtained before, and 2 weeks after, chemoradiation. mRNA levels were evaluated using real-time quantitative polymerase chain reaction formatted in a TaqMan low-density array, which was capable of simultaneously quantifying 46 independent genes in the HH pathway. Protein levels for Patched, Smoothened, and glioma-associated oncogene 1 (Gli-1) in FPE tissues were determined, using immunohistochemistry. A significant concordance (P<0.0001) was observed in the HH-pathway mRNA levels between matched surgically resected (both snap-frozen and FPE) and EUS-FNA biopsies. HH-pathway mRNA levels changed (increased) only after macrodissection, suggesting localization to tumor cells. Immunohistochemical staining for Patched, Smoothened, and Gli-1 confirmed the increased (P<0.001) levels of protein in the PAC cells, compared with cells from uninvolved pancreas. EUS-FNA biopsies that were obtained before and during chemoradiation demonstrated no significant changes in HH-pathway gene expression. Collectively, these studies demonstrate presence of HH-pathway expression in all the clinical PAC biopsies examined, suggesting that this is a significant tumor-associated target and offering the possibility that specific molecular profiling might be attempted from these heterogeneous tissues.     

胰腺癌新辅助治疗和转化治疗的现状与展望

胰腺癌手术切除率低,预后极差。近年来,随着新型药物的出现、治疗手段的多样化及多学科诊疗模式的发展,胰腺癌的新辅助治疗与转化治疗引起了广泛的关注。本文系统梳理了新辅助治疗和转化治疗在胰腺癌中的临床应用以及转化治疗后手术时机的选择,提出将可切除型胰腺癌分为低风险组和高风险组。低风险组患者推荐优先手术切除,高风险组与交界性可切除胰腺癌患者直接手术R0切除率较低,行新辅助治疗后,可明显提高R0切除率。对于不可切除胰腺癌患者应综合评估能否行转化治疗,部分转化有效患者可行根治性手术。然而,胰腺癌新辅助治疗与转化治疗方案的选择、治疗周期及术后辅助方案等问题目前尚无共识。相信伴随高级别循证医学证据的出现,新辅助治疗和转化治疗将在胰腺癌治疗中得到更广泛的应用。     

CXCL12／CXCR4对胰腺癌细胞生物学行为的影响

目的探讨CXCLl2／CXCR4生物轴对胰腺癌细胞增殖、侵袭等生物学行为的影响。方法体外培养胰腺癌细胞系Miapaca-2,将其分为对照组、CXCLl2组和AMD3100组。（1）采用RT—PCR检测胰腺癌细胞中CXCLl2、CXCR4、基质金属蛋白酶-2（MMP-2）、基质金属蛋白酶-9（MMP-9）和人尿激酶型纤溶酶原激活物（uPA）mRNA的表达水平;（2）采用CCK-8法检测各组细胞的增殖情况;（3）采用Transwell侵袭实验检测CXCLl2／CXCR4对胰腺癌细胞趋化活性的影响。结果胰腺癌细胞系Miapaca-2中CXCLl2mRNA未见表达,而CXCR4mRNA在胰腺癌细胞中有表达。MMP-2、MMPO和uPAmRNA在AMD3100组、对照组和CXCLl2组中的表达水平呈递增趋势,差异具有统计学意义（P〈0．05）。胰腺癌细胞的增殖和侵袭能力在CXCLl2组明显增强,而在AMD3100组得到了有效的抑制,组间差异有统计学意义（P〈0．05）。结论趋化因子CXCLl2及其受体CXCR4所构成的生物轴对胰腺癌细胞的增殖和侵袭能力发挥着重要的作用。     

S100A4在类风湿关节炎滑膜中的表达及其对成纤维样滑膜细胞分泌VEGF促进血管生成的影响

目的:研究S100钙结合蛋白A4(S100A4)在类风湿关节炎(rheumatoid arthritis,RA)患者和正常人膝关节滑膜中的表达水平,以及S100A4对类风湿关节炎成纤维样滑膜细胞(rheumatoid arthritis fibroblast-like synoviocytes,RAFLSs)促进血管生成的影响。方法:滑膜分别取自RA患者(RA组)及正常人(control组)膝关节,免疫组化法观察S100A4和VEGF蛋白在2组滑膜中的表达情况。RAFLSs分离自活动性RA滑膜;ELISA法检测S100A4刺激RAFLSs分泌血管内皮生长因子(vascular endothelial growth factor,VEGF)的作用;用rh S100A4孵育RAFLSs的条件培养基作用于人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs),检测S100A4体外血管生成能力。结果:S100A4及VEGF蛋白在RA组滑膜中高表达(P0.05),rh S100A4显著刺激RAFLSs分泌VEGF,呈时间和剂量依赖性(P0.05);rh S100A4孵育RAFLSs的条件培养基可促进HUVECs在体外形成管腔。结论:S100A4蛋白在RA患者膝关节滑膜中高表达,S100A4可通过促进RAFLSs分泌VEGF来刺激滑膜血管生成。这些结果提示S100A4可作为治疗RA的潜在靶点。