A comprehensive in vitro characterization of pancreatic ductal carcinoma cell line biological behavior and its correlation with the structural and genetic profile

There are a large number of stable pancreatic ductal carcinoma cell lines (PDCL) that are used by researchers worldwide. Detailed data about their differentiation status and genetic alterations are present in the literature, but a systematic correlation with cell biological behavior is often lacking. PDCL (n=12) were clustered by source of tumor cell (ascites, primary tumor, metastasis), and the data of functional cell biology were correlated with the reported structural and genetic profiles. Major histocompatibility complex expression, chemosensitivity and aneuploidia appeared to be related to the source of PDCL, and proliferative capacity appeared to be related to the grade of differentiation. No correlation between genetic/structural features of PDCL and biological behavior was found. All the cell lines appeared generally insensitive to in vitro treatment with 5-fluorouracil and showed variable degrees of susceptibility to gemcitabine, raltitrexed and oxaliplatin. All the PDCL showed resistance to Fas-mediated apoptosis but were significantly sensitive to the pro-apoptotic effect of inflammatory cytokines [interleukin (IL)-1, tumor necrosis factor (TNF) and interferon ]. PDCL were characterized for the secretion of several factors relevant to the tumor-immune cross talk. Vascular endothelial growth factor, CCL2, CCL5 and transforming growth factor were the factors most frequently released; less frequent was the secretion of CXCL8, CCL22, IL-6 and sporadically CXCL12, IL-10 and hepatocyte growth factor. The cytokines IL-1 and TNF were always undetectable. In conclusion, a clear correlation between structural/genetic features and function could not be detected, suggesting the weakness of a morphological classification for the in vitro studies of pancreatic cancer.     

智能化穴位温度检测仪的研制及实验研究

在经络穴位的生物物理属性中，由于皮肤温度比较灵敏，易于观察，又能及时反映该处血管的舒缩变化。作者利用铂电阻作为测温控头，用微机进行数据处理，并利用该系统进行人体皮肤温度的检测及分析。结果表明：皮肤温差点基本上是循经分布的。     

胃癌细胞株中NPRA基因启动子区CpG岛的甲基化分析

目的NPRA-cGMP信号通路系统可激活cGMP依赖的蛋白激酶,活化的蛋白激酶调控离子转运蛋白和转录因子的表达,从而最终影响细胞生长、凋亡、增殖和炎症反应。本研究旨在研究NPRA基因在胃癌细胞中的甲基化状态及其对下游mRNA表达的影响。方法应用亚硫酸氢钠处理基因组DNA后PCR并测序,我们分析了6株胃癌细胞株NPRA基因的甲基化状态及去甲基化试剂对下游mRNA表达的影响。结果在胃癌细胞中发现NPRA基因启动子区存在甲基化畸变并导致下游mRNA表达减少或沉默。去甲基化试剂可逆转mRNA表达沉默。结论胃癌细胞中存在NPRA基因甲基化畸变。     

Stimulation by means of dendritic cells followed by Epstein-Barr virus-transformed B cells as antigen-presenting cells is more efficient than dendritic cells alone in inducing Aspergillus f16-specific cytotoxic T cell responses

Adoptive immunotherapy with in vitro expanded antigen-specific cytotoxic T lymphocytes (CTLs) may be an effective approach to prevent, or even treat, Aspergillus (Asp) infections. Such lines can be generated using monocyte-derived dendritic cells (DC) as antigen-presenting cells (APC) but requires a relatively high volume of starting blood. Here we describe a method that generates Asp-specific CTL responses more efficiently using a protocol of antigen presented on DC followed by Epstein-Barr virus (EBV)-transformed B lymphoblastoid cell lines (BLCL) as APC. Peripheral blood mononuclear cells were stimulated weekly (2-5x) with a complete pool of pentadecapeptides (PPC) spanning the coding region of Asp f16 pulsed onto autologous mature DC. Cultures were split and stimulated subsequently with either PPC-DC or autologous PPC-pulsed BLCL (PPC-BLCL). Lines from the DC/BLCL arm demonstrated Asp f16-specific cytotoxicity earlier and to a higher degree than lines generated with PPC-DC alone. The DC/BLCL-primed lines showed a higher frequency of Asp f16-specific interferon (IFN)-gamma producing cells but an identical effector cell phenotype and peptide specificity compared to PPC-DC-only-primed lines. Tumour necrosis factor (TNF)-alpha, but not IL-10, appeared to play a role in the effectiveness of BLCL as APC. These results demonstrate that BLCL serve as highly effective APC for the stimulation of Asp f16-specific T cell responses and that a culture approach using initial priming with PPC-DC followed by PPC-BLCL may be a more effective method to generate Asp f16-specific T cell lines and requires less starting blood than priming with PPC-DC alone.     

Characterization of environmental chemicals with potential for DNA damage using isogenic DNA repair-deficient chicken DT40 cell lines

Included among the quantitative high throughput screens (qHTS) conducted in support of the US Tox21 program are those being evaluated for the detection of genotoxic compounds. One such screen is based on the induction of increased cytotoxicity in seven isogenic chicken DT40 cell lines deficient in DNA repair pathways compared to the parental DNA repair-proficient cell line. To characterize the utility of this approach for detecting genotoxic compounds and identifying the type(s) of DNA damage induced, we evaluated nine of 42 compounds identified as positive for differential cytotoxicity in qHTS (actinomycin D, adriamycin, alachlor, benzotrichloride, diglycidyl resorcinol ether, lovastatin, melphalan, trans-1,4-dichloro-2-butene, tris(2,3-epoxypropyl)isocyanurate) and one non-cytotoxic genotoxic compound (2-aminothiamine) for (1) clastogenicity in mutant and wild-type cells; (2) the comparative induction of γH2AX positive foci by melphalan; (3) the extent to which a 72-hr exposure duration increased assay sensitivity or specificity; (4) the use of 10 additional DT40 DNA repair-deficient cell lines to better analyze the type(s) of DNA damage induced; and (5) the involvement of reactive oxygen species in the induction of DNA damage. All compounds but lovastatin and 2-aminothiamine were more clastogenic in at least one DNA repair-deficient cell line than the wild-type cells. The differential responses across the various DNA repair-deficient cell lines provided information on the type(s) of DNA damage induced. The results demonstrate the utility of this DT40 screen for detecting genotoxic compounds, for characterizing the nature of the DNA damage, and potentially for analyzing mechanisms of mutagenesis.     

Glycosidic intermediates identified in 1H MR spectra of intact tumour cells may contribute to the clarification of aspects of glycosylation pathways

The glycosylation process, through the addition of carbohydrates, is a major post‐translational modification of proteins and glycolipids. Proteins may be glycosylated in either the secretory pathway leading to N‐linked or O‐linked glycoproteins or as nucleocytoplasmic glycosylation that targets only single proteins involving a single β‐linked N‐acetylglucosamine. In both cases, the key precursors are the uridine diphospho‐N‐acetylhexosamines synthesised by the hexosamine biosynthetic pathway. Furthermore, uridine diphospho‐N‐acetylglucosamine participates in the biosynthesis of sialic acid. In this work, we propose MRS for the detection of uridine diphospho‐N‐acetylhexosamines visible in high‐resolution MR spectra of intact cells from different human tumours. Signals from the nucleotide and amino sugar moieties, including amide signals observed for the first time in whole cells, are assigned, also taking advantage of spectral changes that follow cell treatment with ammonium chloride. Finally, parallel changes in uridine diphospho‐N‐acetylhexosamines and glutamine pools, observed after pH changes induced by ammonium chloride in the different tumour cell lines, may provide more details on the glycosylation processes. Copyright © 2010 John Wiley & Sons, Ltd.     

急性髓系白血病血管内皮生长因子表达与预后的研究

目的 :观察人白血病细胞系血管内皮生长因子 (VEGF)表达水平 ,研究急性髓系白血病 (AML)患者血清VEGF表达水平与预后的关系。方法 :采用酶联免疫吸附法 (ELISA)对 4 9例初治、10例复发AML患者血清及人白血病细胞系U937、K5 6 2、HL - 6 0、TF - 1和NB4培养上清液 (4 8小时 )VEGF表达水平进行检测。结果 :五种人白血病细胞系培养上清液中均测到VEGF高表达。 4 9例初治、10例复发AML患者的血清VEGF表达水平分别为 2 0 1 17± 110 93pg ml和 2 32 5 9± 118 6 2pg ml,均明显高于正常对照组 (12 5 6 2± 4 5 4 3pg ml;p <0 0 5 )。初治AML患者中VEGF高表达组 (>2 0 1 17pg ml)完全缓解 (CR)率为 4 8% ,低表达组 (<2 0 1 17pg ml)CR率为 77% ,两者比较差异显著 (p<0 0 5 )。结论 :血管内皮生长因子在刺激白血病细胞增殖、迁移中发挥重要作用。AML患者血清VEGF水平与预后具相关性     

LDL-ACM复合物对裸鼠皮下移植瘤靶向抑制作用的初步研究

目的: 通过观察比较LDL-ACM复合物和游离ACM对胃癌SGC-7901,NKM-45细胞株裸鼠皮下移植的抑制效应,从而了解LDL作为抗癌药物靶向载体的应用价值。方法: 首先采用温育交换法制备LDL-ACM复合物,然后建立人胃癌细胞株裸鼠皮下移植瘤模型,以瘤重、肿瘤体积、白细胞计数、抑瘤率、生命延长率等指标观察LDL-ACM对移植瘤的抑制作用。结果: LDL-ACM组的移植瘤生长速度明显慢于生理盐水组及游离ACM组,抑瘤率和生命延长率明显高于生理盐水组及游离ACM组,外周白细胞计数无明显变化,尤其对SGC-7901瘤更为明显。结论: LDL-ACM复合物与游离ACM相比有更强的抑癌效应。LDL-ACM复合物有可能是通过LDL受体介导起作用。     

Gene and microRNA expression reveals sensitivity to paclitaxel in laryngeal cancer cell line

Paclitaxel is a widely used chemotherapy drug for advanced laryngeal cancer patients. However, the fact that there are 20-40% of advanced laryngeal cancer patients do not response to paclitaxel makes it necessary to figure out potential biomarkers for paclitaxel sensitivity prediction. In this work, Hep2, a laryngeal cancer cell line, untreated or treated with lower dose of paclitaxel for 24 h, was applied to DNA microarray chips for gene and miR expression profile analysis. Expression of eight genes altered significantly following paclitaxel treatment, which was further validated by quantitative real-time PCR. Four up-regulated genes were ID2, BMP4, CCL4 and ACTG2, in which ID2 and BMP4 were implicated to be involved in several drugs sensitivity. While the down-regulated four genes, MAPK4, FASN, INSIG1 and SCD, were mainly linked to the endoplasmic reticulum and fatty acid biosynthesis, these two cell processes that are associated with drug sensitivity by increasing evidences. After paclitaxel treatment, expression of 49 miRs was significantly altered. Within these miRs, the most markedly expression-changed were miR-31-star, miR-1264, miR-3150b-5p and miR-210. While the miRs putatively modulated the mRNA expression of the most significantly expression-altered genes were miR-1264, miR-130a, miR-27b, miR-195, miR-1291, miR-214, miR-1277 and miR-1265, which were obtained by miR target prediction and miRNA target correlation. Collectively, our study might provide potential biomarkers for paclitaxel sensitivity prediction and drug resistance targets in laryngeal cancer patients.     

Effects of transmembrane region variability on cell surface expression and allorecognition of HLA-DP3

The functional relevance of polymorphisms outside the peptide binding groove of HLA molecules is poorly understood. Here we have addressed this issue by studying HLA-DP3, a common antigen relevant for functional matching algorithms of unrelated hematopoietic stem cell transplantation (HSCT) encoded by two transmembrane (TM) region variants, DPB1^*03:01 and DPB1^*104:01. The two HLA-DP3 variants were found at a overall allelic frequency of 10.4% in 201 volunteer stem cell donors, at a ratio of 4.2:1. No significant differences were observed in cell surface expression levels of the two variants on B lymphoblastoid cell lines (BLCL), primary B cells or monocytes. Three different alloreactive T cell lines or clones showed similar levels of activation marker CD107a and/or CD137 upregulation in response to HLA-DP3 encoded by DPB1^*03:01 and DPB1^*104:01, either endogenously on BLCL or after lentiveral-vector mediated transfer into the same cellular background. These data provide, for the first time, direct evidence for a limited functional role of a TM region polymorphism on expression and allorecognition of HLA-DP3 and are compatible with the notion that the two variants can be considered as a single functional entity for unrelated stem cell donor selection.