CHARACTERIZATION OF A BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATUS) KIDNEY EPITHELIAL CELL LINE

Abstract: An epithelial cell line, Carvan dolphin kidney (CDK), isolated from a prematurely born female bottlenose dolphin, Tursiops truncatus , exhibited growth characteristics not previously reported for cetacean cells in culture. CDK cells were cytokeratin positive and demonstrated a maximum doubling time of 1.31 days, with plating and colony forming efficiencies approaching 100% for the early population doublings. Despite an unusually efficient colony-forming ability and rapid growth, these cells were neither transformed nor immortal, displaying normal contact inhibition, anchorage dependence, and the requirement for high concentrations of fetal bovine serum in the growth medium. CDK cells exhibited age-dependent changes in growth rate, colony-forming efficiency, and cytoplasmic profile, and showed a finite lifespan of about 50 population doublings and a stable 2N = 44 karyotype which correlates with previously reported cytogenetic analyses. Velocity sedimentation analysis showed that CDK cells contained nuclear aryl hydrocarbon receptor (Ah), indicating their potential to be induced for cytochrome P450. These data suggest that CDK cells may have utility as an in vitro toxicological model for evaluating hydrocarbon contaminant effects on Tursiops truncatus , a protected marine mammal.     

Enhanced expression of group II phospholipase A2 in human hepatocellular carcinoma

Enzyme activity, protein contents, and mRNA contents of group II phospholipase A₂ (PLA₂) in hepatocellular carcinoma (HCC) surgically obtained from 8 patients were compared with those in either its neighboring liver tissues or control liver tissues. The PLA₂ specific activity towards the mixed micelles of 1-palmitoyl-2-oleoyl-phosphatidylglycerol and cholate was significantly greater in the tumor tissues (6.62 ± 1.46 nmol/min/mg) than those in the surrounding liver tissues (1.33 ± 0.22 nmol/min/mg) and controls (0.43 ± 0.04 nmol/min/mg). The results of immunoblot analysis using a specific anti-human group II PLA₂ antibody and of Northern blot analysis using a human group II PLA₂ cDNA as a probe demonstrated that group II PLA₂ was responsible for the increased enzyme activity. The contents of immunoreactive group II PLA₂ in the tumor tissues (8.81 ± 1.24 ng/mg) were significantly higher than those in the surrounding liver tissues (1.77 ± 0.27 ng/mg); those in the control tissues were below the analytical range of the method used. The group II PLA₂ mRNA was also significantly increased in the tumor tissues, compared with that in the surrounding liver tissues, whereas it was not detectable in th controls. This indicates that group II PLA₂ in HCC is induced at the pretranslational level.     

非同位素PCR－单链构象多态性技术的建立和应用

ＰＣＲ－单链构象多态性技术问世以来,成为研究基因突变的工具,特别是在分子肿瘤学研究中,广泛应用于癌基因,抑癌基因突变的研究,常规ＰＣＲ－ＳＳＣＰ采用同位素标记ＰＣＲ产物,测序板电泳分离突变,在操作和费用上有种种局限,文章建立了一种非同位素ＰＣＲ－ＳＳＣＰ技术;通过不对称ＰＣＲ获得单链,普通ＰＡＧＥ分离,经银染检出突变,用这种方法,还研究了四株鼻咽癌细胞株ＣＮＥ１,ＣＮＥ２,ＨＫ１和ＳＵＮＥ１中肿瘤     

Primary renal hemangiosarcoma in a moustached tamarin

A wild-caught adult female Saguinus mystax died after 54 months in captivity. At necropsy, a small reddish zone in the renal cortex of one kidney was shown histologically to be a hemangiosarcoma.     

人结肠癌(CCA)单克隆抗体及其识别抗原的分析(简报)

正常细胞转化成癌细胞后,其表型发生了一系列不同于正常细胞的变化,成为肿瘤细胞的标志。Gold和Freeman(1965)用人结肠癌组织的抽提物免疫兔,发现有些用人正常结肠组织吸收后的抗血清能够与肿瘤组织和胚胎肠道抽提物起反应,但不与正常组织抽提物起反应,由于这种抗原最初被发现在胚胎组织,故名为癌胚抗原(embryonic carcinoma antigen,简称CEA)。用敏感的放射免疫或免疫酶标方     

PCR检测HPV－18DNA

采用聚合酶链式反应（ＰＣＲ）技术,对ＨＰＶ－１８序列中引物ＨＰ＿１、ＨＰ＿２之间的片段（Ｆ）进行扩增,通过两组阴、阳性对照实验证明扩增片段的特异性。用不同Ｍｇ浓度的缓冲系统进行ＰＣＲ反应发现,缓冲系统中Ｍｇ浓度高低是影响ＨＰＶ－１８／ＨＰ＿１、ＨＰ＿２特异扩增的重要因素,高浓度Ｍｇ导致扩增特异性降低。对１７例宫颈癌组织ＤＮＡ进行ＰＣＲ检测,有９例检出Ｆ片段,其检出率是５３％,为ＨＰＶ－１８与宫颈癌的相关性提供证据。     

Release of fibroblast growth factor-1 by human squamous cell carcinoma correlates with autocrine cell growth

Summary A squamous cell carcinoma cell line Nakata proliferated in serum-free culture and was not responsive to exogenous fibroblast growth factor-1 (FGF-1). Immunostaining revealed that Nakata cells expressed FGF-1 in their cytoplasms and nuclei. Two molecular mass species of FGF-1 (16 and 18 kDa) were identified in cell extracts by Western blot. These cells also expressed high-affinity FGF-1 binding sites (Kd=360 pM, 28 000 sites/cell). The results of cross-linking with [¹²⁵I]FGF-1 demonstrated the presence of two bands with molecular masses of 160 and 140 kDa. The addition of FGF-1 specific antisense oligonucleotides at 25 μM to Nakata cells resulted in an 82% inhibition in cell growth and suppressed FGF-1 expression. This effect was dose-dependent and specific, because sense oligonucleotides were ineffective in inhibiting cell growth. In addition, Nakata cell growth was suppressed by an anti-FGF-1 neutralizing antibody, which resulted in a 52% inhibition at 8 μg/ml. These results demonstrate that Nakata cells produce FGF-1, and indicate that this growth factor acts in an autocrine manner by interacting with FGF-1 binding sites on Nakata cells.