Expression of fetoacinar pancreatic (FAP) protein in the pancreatic human tumor cell line BxPC-3

Fetoacinar pancreatic (FAP) protein is a specific component of the human exocrine pancreas that may have a role in the differentiation and transformation of this organ. In order to set out a model for studies on the regulation of FAP, 47 established cell lines from human cancer of different origins were tested for FAP expression using the monoclonal antibody J28 (Mab J28). Only two, both pancreatic, were positive. This finding supports the already reported pancreatic specificity of this antigen. Strongest expression was shown by the BxPC-3 cell line, derived from a moderately well-differentiated adenocarcinoma in the body of the pancreas. In BxPC-3 cells grown in Roswell Park Memorial Institute (RPMI) 1640-10% fetal bovine serum (FBS), Mab J28 immunostaining was localized in the cytoplasm of the cells. In serum-free medium, cells quickly died. Growth and FAP expression were maintained when this medium was supplemented with insulin. FAP is not released to the culture medium, as evidence by absence of reaction with the monoclonal antibody on nitrocellulose dot-blots. On the contrary, a positive reaction was observed in cell homogenates made by sonication or by extraction with 0.1% Triton. A competitive enzyme-linked immunosorbent assay (ELISA), using biotinylated FAP, was developed to quantify the protein in cell homogenates. Concentrations of FAP in homogenates from cells cultured in standard conditions or serum-free supplemented with insulin were in the range of 0.28-0.40 micrograms FAP/mg total protein.(ABSTRACT TRUNCATED AT 250 WORDS)     

Antiproliferative effects of natural human tumor necrosis factor-alpha, interferon-alpha, and interferon-gamma on human pancreatic carcinoma cell lines

The antiproliferative effects of natural human tumor necrosis factor-alpha (nHuTNF-alpha), natural human interferon-alpha (nHuIFN-alpha), and natural human interferon-gamma (nHuIFN-gamma) were investigated in human pancreatic carcinoma cell lines. HuP-T3, HuP-T4, and BxPC-3 carcinoma cells exhibited mild growth inhibition after treatment with nHuTNF-alpha. HuP-T3, HuP-T4, MIA-PaCa-2, and BxPC-3 cells exhibited mild or marked growth inhibition after treatment with nHuIFN-alpha. Incubation with nHuIFN-gamma caused marked growth inhibition of HuP-T4 and BxPC-3 cells, whereas HuP-T1, HuP-T3, and MIA-PaCa-2 cells showed only mild growth inhibition with the same dose of nHuIFN-gamma. Combined nHuTNF-alpha and nHuIFN-alpha (1:1) demonstrated marked synergism in comparison with their effects as single agents on HuP-T1, HuP-T3, and MIA-PaCa-2 cells. The combination of nHuTNF-alpha and nHuIFN-gamma (100:1) also demonstrated a marked synergistic effect in comparison with these cytokines alone in four out of five pancreatic carcinoma cell lines (HuP-T1, HuP-T3, HuP-T4, and MIA-PaCa-2 cell lines). The marked increase in efficacy brought about by using combinations of cytokines may enable some improvement in the treatment of pancreatic carcinoma patients in the future.     

Pancreatic secretory trypsin inhibitor stimulates the growth of rat pancreatic carcinoma cells

Pancreatic secretory trypsin inhibitor was examined for growth-promoting activity on five cell lines using standard cell culture techniques. One cell line, AR4-2J, derived from a rat pancreatic acinar cell carcinoma, responded with significantly increased incorporation of [3H]thymidine and colony formation. Pancreatic secretory trypsin inhibitor stimulated the incorporation of [3H]thymidine in liquid culture; the maximal increase was 61 +/- 10% above control (P less than 0.001) and was seen at a concentration of 10(-9) mol/L. Using a soft agarose clonogenic assay, pancreatic secretory trypsin inhibitor also consistently stimulated (3 assays) colony formation: the peak activity occurred at a concentration of 10(-10) mol/L which caused a 150 +/- 55% (mean +/- SE, P less than 0.05) increase above control. Aprotinin had no effect on the growth of AR4-2J cells and pancreatic secretory trypsin inhibitor did not bind to the epidermal growth factor receptor. AR4-2J cells were shown to produce pancreatic secretory trypsin inhibitor. The study raises the possibility that pancreatic secretory trypsin inhibitor provides autocrine stimulation of tumor cell growth.     

Trophic effects of unsulfated cholecystokinin on mouse pancreas and human pancreatic cancer.

The effect of unsulfated cholecystokinin on pancreatic growth was evaluated in two experimental models in vivo and in vitro. Mice were injected with sulfated cholecystokinin (CCKs) or unsulfated cholecystokinin (CCKu) (10 or 20 micrograms/kg) or vehicle twice daily for 15 days. Animals were then killed and pancreatic weights, protein, amylase, and DNA content were evaluated. In vitro, growth was evaluated by DNA synthesis and viable cell counts. MIA PaCa-2 and BxPC-3 human pancreatic cancer cells were treated with CCKs or CCKu (10(-12) to 10(-9) M) for 48 or 72 h in the presence of [3H]thymidine to evaluate DNA synthesis. Viable cell counts were performed on both cell lines grown in the presence or absence of unsulfated CCK (10(-12) to 10(-9) M) for 96 h. Pancreatic weight, protein, amylase, and DNA were significantly increased in animals treated with either CCKs or CCKu. However, pancreatic weight, protein, and amylase were significantly higher in mice treated with CCKs compared to CCKu (p less than 0.005). DNA content and index of hyperplasia were the same whether mice were treated with CCKs or CCKu. CCKu was as potent a stimulus for DNA synthesis as CCKs in MIA PaCa-2 and BxPC-3 cells. Finally, CCKu increased cell counts in both pancreatic cancer cell lines. These data suggest that the mechanisms responsible for CCK-induced growth of normal pancreas and pancreatic cancer may differ from those that regulate secretion.     

Establishment and characterization of a carcinoembryonic antigen producing cell line derived from human pancreatic exocrine cancer

A human pancreatic carcinoma cell line derived from well differentiated tubular adenocarcinoma of the pancreas head has been established and maintained for nearly 4 years. This established cell line produces and releases carcinoembryonic antigen into the culture medium. The cell line grows as a monolayer in RPMI-1640 medium containing 10 percent fetal calf serum. Xenotransplantation in athymic nude mice after subcutaneous injection of EDTA-trypsin treated cells did not succeed.     

Growth effects of regulatory peptides on human pancreatic cancer lines PANC-1 and MIA PaCa-2

Several studies have reported effects of gastrointestinal regulatory peptides on growth of experimentally induced pancreatic neoplasms and human cancer cell lines. The growth of human pancreatic cancer lines PANC-1 and MIA PaCa-2 was characterized in vitro, and the effects of cholecystokinin, bombesin, insulin, epidermal growth factor, secretin, vasoactive intestinal peptide, and somatostatin were determined. Fetal bovine serum was required for initiation of growth in both cell lines. Growth effects of peptides were determined by incubating cells with peptides in serum-free medium after a 72-h preincubation in 10% serum-supplemented medium alone. Epidermal growth factor (3.4 x 10(-9) M) and insulin (10(-6) M) significantly (p less than 0.001) increased growth of both cell lines as determined by increases in deoxyribonucleic acid and protein. Bombesin, secretin, vasoactive intestinal peptide, and somatostatin (all 10(-8) M) did not affect growth of either cell line. Neither cholecystokinin-8 nor [Thr4, Nle7] cholecystokinin-9 altered growth in concentrations from 10(-12)-10(-6) M. Anchorage-dependent clonogenic growth of both cell lines was also not altered by cholecystokinin-8. Cholecystokinin added to cultures was degraded by separate effects of serum and cells. Addition of cholecystokinin-8 to cultures every 8 h maintained cholecystokinin levels but did not alter cell growth. These data support roles for epidermal growth factor and insulin as growth factors for human pancreatic cancer cell lines.     

吲哚美辛与埃罗替尼对胰腺癌细胞生长的协同抑制作用

背景：目前胰腺癌药物化疗疗效不佳。既往研究提示环氧合酶（COX）-2和表皮生长因子受体（EGFR）信号途径均参与了胰腺癌的发生、发展，COX-2抑制剂和EGFR抑制剂联用对胰腺癌的生长可能具有协同抑制作用。目的：观察COX-2抑制剂吲哚美辛与EGFR酪氨酸激酶抑制剂埃罗替尼对胰腺癌细胞生长的协同抑制作用。方法：以甲基噻唑基四唑（MTT）比色法检测胰腺癌细胞株BxPC-3的增殖情况，以流式细胞分析和原位末端标记（TUNEL）法观察用药前后细胞凋亡和细胞周期的变化，以逆转录聚合酶链反应（RT—PCR）观察用药前后细胞中COX-2、EGFR以及凋亡相关基因Bcl-2、Bax、Bcl-xL、Bak mRNA表达的变化。结果：BxPC-3细胞中可观察到COX-2和EGFRmRNA表达．吲哚美辛和埃罗替尼单用均可下调COX-2和EGFRmRNA的表达，两者联用时下调作用更明显。吲哚美辛和埃罗替尼单用均可抑制BxPC-3细胞增殖，促进细胞凋亡，诱导细胞周期阻滞于G0／G1期，减少抗凋亡基因Bcl-2、Bcl-xL的表达，轻微上调促凋亡基因Bax的表达，两者联用对细胞生长的抑制作用增强。结论：吲哚美辛和埃罗替尼均可抑制COX-2和EGFR的表达，下调Bcl-2／Bax比值，两者联用对胰腺癌细胞生长具有协同抑制作用。     

Somatostatin receptor subtype 2 sensitizes human pancreatic cancer cells to death ligand-induced apoptosis

Somatostatin receptor subtype 2 (sst2) gene expression is lost in 90% of human pancreatic adenocarcinomas. We previously demonstrated that stable sst2 transfection of human pancreatic BxPC-3 cells, which do not endogenously express sst2, inhibits cell proliferation, tumorigenicity, and metastasis. These sst2 effects occur as a consequence of an autocrine sst2-dependent loop, whereby sst2 induces expression of its own ligand, somatostatin. Here we investigated whether sst2 induces apoptosis in sst2-transfected BxPC-3 cells. Expression of sst2 induced a 4.4- +/- 0.05-fold stimulation of apoptosis in BxPC-3 through the activation of tyrosine phosphatase SHP-1. sst2 also sensitized these cells to apoptosis induced by tumor necrosis factor alpha (TNFalpha), enhancing it 4.1- +/- 1.5-fold. Apoptosis in BxPC-3 cells mediated by TNF-related apoptosis-inducing ligand (TRAIL) and CD95L was likewise increased 2.3- +/- 0.5-fold and 7.4- +/- 2.5-fold, respectively. sst2-dependent activation and cell sensitization to death ligand-induced apoptosis involved activation of the executioner caspases, key factors in both death ligand- or mitochondria-mediated apoptosis. sst2 affected both pathways: first, by up-regulating expression of TRAIL and TNFalpha receptors, DR4 and TNFRI, respectively, and sensitizing the cells to death ligand-induced initiator capase-8 activation, and, second, by down-regulating expression of the antiapoptotic mitochondrial Bcl-2 protein. These results are of interest for the clinical management of chemoresistant pancreatic adenocarcinoma by using a combined gene therapy based on the cotransfer of genes for both the sst2 and a nontoxic death ligand.     

Insulin-like growth factor binding protein-5 influences pancreatic cancer cell growth

AIM： To investigate the functional significance of insulin-like growth factor binding protein-5 （IGFBP-5） overexpression in pancreatic cancer （PaC）.
METHODS： The effects of IGFBP-5 on cell growth were assessed by stable transfection of BxPC-3 and PANC-1 cell lines and measuring cell number and DNA synthesis. Alterations in the cell cycle were assessed by flow cytometry and immunoblot analyses. Changes in cell survival and signal transduction were evaluated after mitogen and phosphatidylinositol activated protein kinase 3-kinase （PI3K） inhibitor treatment.
RESULTS： After serum deprivation, IGFBP-5 expression increased both cell number and DNA synthesis in BxPC-3 cells, but reduced cell number in PANC-1 cells. Consistent with this observation, cell cycle analysis of IGFBP-5-expressing cells revealed accelerated cell cycle progression in BxPC-3 and G2/M arrest of PANC-1 cells. Signal transduction analysis revealed that Akt activation was increased in BxPC-3, but reduced in PANC-1 cells that express IGFBP-5. Inhibition of PI3K with LY294002 suppressed extracellular signal-regulated kinase-1 and -2 （ERK1/2） activation in BxPC-3, but enhanced ERK1/2 activation in PANC-1 cells that express IGFBP-5. When MEK1/2 was blocked, Akt activation remained elevated in IGFBP-5 expressing PaC cells; however, inhibition of PI3K or MEK1/2 abrogated IGFBP-5-mediated cell survival.
CONCLUSION： These results indicate that IGFBP-5 expression affects the cell cycle and survival signal pathways and thus it may be an important mediator of PaC cell growth.     

维生素D衍生物EB1089对胰腺癌细胞系BxPC-3生长的抑制作用

目的：观察维生素D衍生物EB1089对人胰腺癌细胞系BxPC-3的生长抑制作用及其可能机制。方法：应用MTT比色法、流式细胞术、Western blot法免疫印记电泳进行检测。结果：EB1089抑制人胰腺癌细胞系BxPC-3的生长，抑制50％细胞生长的药物浓度(IC50)为10^-7mmol／L。癌细胞在EB1089作用下，G0／G1期细胞比例增加23％，S期细胞比例下降12％。胰腺癌细胞系BxPC-3的p21蛋白的表达随EB1089的作用时间和药物浓度的提高而增强。结论：EB1089对胰腺癌细胞系：BxPC-3具有生长抑制作用，其作用机制可能与p21表达上调有关。     

Alteration of integrins by interleukin-1alpha in human pancreatic cancer cells

INTRODUCTION: Adhesion of tumor cells to extracellular matrix (ECM) proteins plays an important role in tumor invasion and metastasis. AIMS: To investigate the expression of integrins in human pancreatic cancer cell lines and its alteration by interleukin (IL)-1alpha to examine the mechanism of adhesion of metastatic human pancreatic cancer cells to ECM proteins. METHODOLOGY: The expression of integrin subunits and their alteration by IL-1alpha were examined by flow-cytometric analysis and cellular enzyme-linked immunosorbent assay in three metastatic human pancreatic cancer cell lines (AsPC-1, BxPC-3, and SW1990) and two nonmetastatic cancer cell lines (PaCa-2 and PANC-1). In addition, assays of cancer cell adhesion to ECM proteins were performed to investigate if increased integrin expression actually affected the adhesive interaction between cancer cells and the putative integrin ECM ligands. RESULTS: The alpha(6) subunit expressed in metastatic cancer cells was enhanced by IL-1alpha. Metastatic cancer cells also showed preferential adherence to laminin compared with nonmetastatic cancer cells, and this was enhanced by IL-1alpha. CONCLUSION: In pancreatic cancer, the enhancement of alpha(6)beta(1) integrin by IL-1alpha through IL-1 receptor type I, as well as the expression of alpha(6)beta(1) integrin, plays an important role in metastasis formation.     

Primary culture of porcine pancreatic acinar cells

INTRODUCTION: The methodology of acinar cell culture has become of primary importance in the research of pancreatic physiology and pharmacology. AIM: To develop a method for primary culture of porcine pancreatic acinar cells. METHODOLOGY: Dispersed pancreatic acinar cells were made by RPMI-1640 medium containing collagenase III. After purification, the isolated acinar cells were cultured in RPMI-1640 medium with 2.5% fetal bovine serum. The morphologic characteristics of acinar cells were described. (3)H-thymidine incorporation of acinar cells and activity of amylase or lipase were determined during the culture. RESULTS: There were no remarkable morphologic changes in the pancreatic acinar cells during the 20-day culture. The acini showed the tendency of gathering but did not attach to the walls of the culture disks. Incorporation of (3)H-thymidine in acinar cells in the primary culture was well kept. The secretion of amylase or lipase from acini decreased with the time of culture. CONCLUSIONS: In the primary culture of acinar cells from porcine pancreas developed in this study, the acinar cells retained normal morphology and ability of growth but not secretion of amylase or lipase. The method would be beneficial for further experiments on acini of porcine pancreas.     

帕瑞昔布对人胰腺癌细胞株BxPC-3、AsPC-1增殖凋亡的影响及其机制

目的:研究帕瑞昔布(parecoxib,PCB)对人胰腺癌细胞株BxPC-3和AsPC-1的增殖、凋亡及其可能的分子机制.方法:BxPC-3、AsPC-1细胞用不同浓度PCB的培养液孵育后,利用MTT法测定细胞活性,计算IC50值,TUNEL法检测处理后细胞的凋亡情况,RT-PCR验证相关蛋白的变化表达.结果:PCB对两种细胞生长呈时间和计量依赖性抑制;PCB处理后BxPC-3、AsPC-1两种细胞IC50值为:400.98μmol/L±10.78μmol/L、256.3μmol/L±2.98μmol/L;TUNEL法检测证明凋亡率增加;RT-PCR显示COX-2表达明显降低.结论:PCB可以抑制胰腺癌细胞增殖,并诱导其凋亡生长,其可能机制是通过抑制COX-2表达来实现的.     

花姜酮对胰腺癌细胞迁移和侵袭的影响及机制的研究

目的:探讨花姜酮(zerumbone)对人胰腺癌细胞株BxPC-3和Panc-1迁移和侵袭的影响及其相关基因的表达。方法:以BxPC-3和Panc-1为研究对象,通过四甲基偶氮唑盐(MTT)实验选择毒性较小的花姜酮浓度,用细胞划痕实验、Transwell小室迁移和侵袭实验检测药物对细胞迁移和侵袭能力的影响,蛋白质印迹(Western blot)检测各细胞组CXC族趋化因子受体4(CXCR4)、促分裂原活化蛋白酶激酶1/2(MEK1/2)、磷酸化MEK 1/2(p-MEK1/2)、细胞外调节激酶1/2(ERK1/2)、磷酸化ERK1/2(p-ERK1/2)蛋白表达变化。结果:花姜酮对BxPC-3和Panc-1细胞的生长均有抑制作用,且随着药物浓度的增高和作用时间的延长而增强(P<0.05)。低浓度药物作用后BxPC-3和Panc-1的划痕迁移率都低于对照组(P<0.05)。与对照组相比,Transwell迁移和侵袭实验中BxPC-3和Panc-1用药组的平均穿膜细胞数均减少(P     

慢病毒载体介导CD55抑制对胰腺癌BxPC-3细胞迁移、侵袭和成瘤的影响

目的探讨慢病毒载体介导的RNA沉默CD55基因抑制胰腺癌BxPC-3细胞迁移、侵袭和成瘤的效果及机制。方法采用CD55-RNAi-LV(慢病毒包装靶向抑制CD55的shRNA载体)转染BxPC-3细胞(实验组),设转染NC-GFP-LV(慢病毒包装作对照的空载体)的BxPC-3细胞为对照组,未转染的BxPC-3细胞为空白组。Transwell法检测各组细胞体外迁移、侵袭能力。三组细胞分别以1.0×107/200μL的浓度注入裸鼠皮下,7周观察成瘤情况。结果与对照组及空白组比较,实验组细胞迁移能力及侵袭能力明显减弱(P均<0.05);瘤体出现晚且瘤体体积小(P<0.05)。结论 CD55基因对胰腺癌细胞系BxPC-3细胞迁移、侵袭和成瘤能力有调控作用,可望成为胰腺癌新的治疗靶点。     

STAT3基因沉默对胰腺癌细胞株的增殖及对吉西他滨敏感性的影响

目的 探讨信号转导与转录激活因子3（STAT3）基因沉默对吉西他滨介导的胰腺癌细胞株增殖和凋亡及对吉西他滨治疗敏感性的影响.方法 以STAT3荧光素慢病毒及对照的海肾萤光素酶慢病毒感染6株胰腺癌细胞株（BxPC3、L3.6pl、CFPAC-1、MPanc-96,PANC1、MiaPaCa-2）及人胰腺癌导管上皮细胞株（HPDE）,检测各细胞STAT3及磷酸化STAT3（pSTAT3）蛋白的表达.应用RNA干扰技术沉默6株胰腺癌细胞株STAT3基因表达,应用蛋白质印迹法检测细胞STAT3蛋白表达,MTS法检测细胞的增殖,流式细胞仪检测细胞的凋亡.结果 6株胰腺癌细胞株STAT3及pSTAT3蛋白表达量均显著高于HPDE细胞,但胰腺癌细胞的表达量与其对吉西他滨耐药性及敏感性无明显相关.转染靶向STAT3的siRNA（siSTAT3）的BxPC3、MiaPaCa-2、PANC1、L3.6pl、CFPAC-1、MPanc-96细胞STAT3蛋白表达量分别为0.40±0.04、0.09±0.01、0.38±0.02、0.27 ±0.06、0.10±0.02、0.24±0.04,较转染阴性对照siRNA（siNC）细胞的表达量2.27±0.21、1.83 ±0.12、2.27±0.17、2.23±0.21、0.33±0.05、1.24±0.19均显著下降（P值均＜0.05）.但对细胞的增殖及凋亡无明显影响.STAT3基因沉默可以增加所有6株细胞对吉西他滨的敏感性,吉西他滨的杀伤效应增加了10％～15％.结论 STAT3表达水平同胰腺癌的化疗药物耐药性无明显相关性,沉默STAT3基因表达可增加细胞对吉西他滨耐治疗的敏感性.