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1.
 以人肺癌细胞 P G 和人胃癌细胞 B G C 823 作为研究对象,利用 M T T 测定、3 H Td R 参入、流式细胞术、软琼脂培养、 Northern blot、 W stern blot 等实验方法,观察了稀土化合物氯化亚鈰( Ce Cl3)抑癌作用.结果表明, Ce Cl3 浓度为 005 m m ol/ L,01 m m ol/ L,05 m m ol/ L和 1 m m ol/ L可抑制 P G 细胞的增殖;浓度为 05 m m ol/ L和 1 m m ol/ L可抑制 P G 细胞 D N A 的合成,其 G1 期细胞比例增加而 S期细胞比例减少,在软琼脂中的生长能力降低,原癌基因 c m yc 和 c ras 表达降低,p16 蛋白质表达降低.而同样浓度的 Ce Cl3 对 B G C 823 细胞和正常细胞 2 B S未见影响.提示:稀土化合物抑制肺癌细胞 P G 的增殖以及降低其恶性度的作用机制可能与一些增殖相关的原癌基因的表达和细胞周期的调控有关,其确切的机理还需进一步的研究.  相似文献   

2.
本文利用Northern印迹分析技术研究了完全致癌物二甲基苯蒽(DMBA)对小鼠表皮鸟氨酸脱羧酶(ODC)mRNA和转化生长因子β(TGF-β)mRNA水平的影响。DMBA在15μg和900μg剂量下一次涂用于小鼠皮肤,可使表皮ODCmRNA和TGF-βmRNA表达增加。ODCmRNA为单一的2.0kb大小的条带,其表达在在36h时最为明显。而TGF-βmRNA大小为2.5kb和1.9kb,其表达在36h时最高,到48h几乎降至正常,但在72h又有增加。ODC和TGF-β可能在DMBA诱癌过程中起重要作用。  相似文献   

3.
本文利用Northern印迹分析技术研究了完全致癌物二甲基苯蒽(DMBA)对小鼠表皮鸟氨酸脱羧酶(ODC)mRNA和转化生长因子β(TGF-β)mRNA水平的影响。DMBA在150μg和900μg剂量下一次涂用于小鼠肝肤,可使表皮ODC mRNA和TGF-βmRNA表达增加。ODC mRNA为单一的2.0kb大小的条带,其表达在在36h时最为明显。而TGF-βmRNA大小为2.5kb和1.9kb,  相似文献   

4.
给大白鼠侧脑室注射马桑内酯(Coriaria Lactone, CL)(175×10- 2m ol/L2μl)后可诱发癫痫,用NADPHd 组织化学方法观察大脑皮质及海马NOS阳性神经元的变化, 结果: 大脑皮质NOS阳性神经元数目逐渐增加, 至2h 达高峰, 与生理盐水组相比差异具有非常显著性意义(P< 001), 随着CL作用时间延长NOS反应由弱变强;海马区NOS阳性神经元2h 时才出现染色明显加深。对体外培养的大脑皮质及海马神经元用CL (25×10- 5m ol/L) 作用1/2h、1h、2h、4h 后NOS阳性神经元均未见明显增加。  相似文献   

5.
从 He La 细胞中提取总 R N A,采用反转录 P C R 技术,从该总 R N A 中扩增了约 530 bp 的sh T N F R55 基因的 c D N A,并克隆至质粒 p U C m el中酪蛋白酶 m el Cl 分泌信号肽编码序列的下游,构建成含融合基因 m el/ T N F R 的重组质粒 p U C m el/ T N F R.把融合基因 m el/ T N F R 插入链霉菌表达质粒 p I J459 的多克隆位点,使之位于 erm 强启动子的下游,得到重组表达质粒 p I J459 m el/s T N F R.经 Southern 杂交证明重组质粒 p I J459 m el/s T N F R 插入了 s T N F R55 基因片段.对重组菌株 Streptom yces lividans(p I J459 m el/s T N F R)的发酵液进行 S D S P A G E、受体配基杂交( Ligand blot)分析、对 T N F 敏感的 L929 细胞的细胞毒性中和试验表明,可溶性肿瘤坏死因子受体 s T N F R55 在链霉菌中得到了分泌表达,表达产物具有生物学活性.表达产物的分子量约在 26~28 k D 之间.  相似文献   

6.
通过培养的人主动脉平滑肌细胞(hASMC)及脐静脉内皮细胞(hUVEC),应用^3H-TdR参入、Northern blot分析、逆转录多聚酶链反应(RT-PCR)、放射免疫分析(RIA)、和紫外比色法等技术观察了人主动脉中硫酸乙酰肝素蛋白聚糖(HSPG)对hASMC和hUVEC DNA合成的作用及对血小板源生长因子(PGDF)、PGDF受体、转化生长因子β(TGF-β)、内皮素-1(ET-1)或  相似文献   

7.
黑龙江铜木蚜蝇雌性的描述DESCRIPTIONOFTHEFEMALECHALCOSYRPHUS(XYLOTOMIMA)AMURENSIS(STACKELBERG)(DIPTERA:SYRPHIDAE)¥HEJilong;CHUXiping(Depar...  相似文献   

8.
动脉平滑肌细胞(sm ooth m uscle cell,SMC)是动脉粥样硬化(atherosclerosis,AS)斑块中的主要细胞,它的增殖在AS形成过程中极其重要.利用体外培养的人主动脉SMC,观察了天然高密度脂蛋白(native high density lipoprotein,N-HDL)及氧化修饰HDL(oxidized HDL,OX-HDL)对培养人主动脉SMC cyclin D1(细胞周期蛋白D1)基因转录表达的影响.结果表明:(1)N-HDL对SMCcyclin D1基因表达无影响(P> 0.05);(2)OX-HDL使SMCcyclin D1基因表达显著增强(P<0.01),其表达量随时间(2、12、24 h)延长而增加.上述结果表明,OX-HDL的致AS作用可能与其刺激SMCcyclin D1基因表达增加有关.  相似文献   

9.
应用聚合酶链反应技术,用设计带有限制性酶切位点的引物,特异地扩增从起始密码子开始的1 .8 kb 新城疫病毒( N D V) 血凝素神经氨酸酶( H N) 基因开放式阅读框,然后插入p T K2 B 的 Nhe Ⅰ位点,构建了含 N D V H N 基因的插入载体p T K H N1 和p T K H N2 ,再与感染火鸡疱疹病毒( H V T) 细胞的总 D N A 共转染鸡胚成纤维细胞( C E F) ,经有限稀释法和 Dotblot 筛选,得到含有 H N 基因的重组体r H V T1 和r H V T2 。经组织培养传代和 Western blot 分析,表明重组体在感染细胞中表达了 H N 蛋白。重组体在 C E F 上的生长特性与亲本病毒相同,且在连续传代过程中保持稳定。为国内新城疫基因工程疫苗研制奠定了基础。  相似文献   

10.
STUDIESONTHEPATTERNOFMEGASPOROGENESISANDMICROTUBULARCYTOSKELETONCHANGESINCYMBIDIUMSINENSE¥S.Y.ZeeX.L.Ye(1BotanyDepartment,Uni...  相似文献   

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Dehydroepiandrosterone (DHEA) is commonly used as a dietary supplement and may affect prostate pathophysiology when metabolized to androgens and/or estrogens. Human prostate LAPC-4 cancer cells with a wild type androgen receptor (AR) were treated with DHEA, androgens dihydrotestosterone (DHT), T, or R1881), and E(2) and assayed for prostate specific antigen (PSA) protein and gene expression. In LAPC-4 monocultures, DHEA and E(2) induced little or no increase in PSA protein or mRNA expression compared to androgen-treated cells. When prostate cancer-associated (6S) stromal cells were added in coculture, DHEA stimulated LAPC-4 cell PSA protein secretion to levels approaching induction by DHT. Also, DHEA induced 15-fold more PSA mRNA in LAPC-4 cocultures than in monocultures. LAPC-4 proliferation was increased 2-3-fold when cocultured with 6S stromal cells regardless of hormone treatment. DHEA-treated 6S stromal cells exhibited a dose- and time-dependent increase in T secretion, demonstrating stromal cell metabolism of DHEA to T. Coculture with non-cancerous stroma did not induce LAPC-4 PSA production, suggesting a differential modulation of DHEA effect in a cancer-associated prostate stromal environment. This coculture model provides a research approach to reveal detailed endocrine, intracrine, and paracrine signaling between stromal and epithelial cells that regulate tissue homeostasis within the prostate, and the role of the tumor microenvironment in cancer progression.  相似文献   

13.
To assess the role of hepatocyte growth factor (HGF) and androgen in growth of prostate epithelial cells, we isolated mouse ventral prostate epithelial cells and cultured them in a three-dimensional type I collagen gel matrix under serum-free conditions. Although the prostate epithelial cells tended to die in the insulin-supplemented basal medium, 5alpha-dihydrotestosterone (DHT) prevented the cell death, and HGF slightly stimulated the growth. By contrast, coexistence of DHT and HGF greatly augmented the growth and branching morphogenesis of the epithelial cells. Some of the outgrowths formed under these conditions showed enlarged structures resembling the prostate ducts or alveoli. Examination of the stromal cell-conditioned medium revealed that a growth-stimulating activity is present in the conditioned medium. A major portion of this activity was abolished by anti-HGF IgG. These observations suggest that HGF is produced by the stromal cells of the prostate gland and supports the androgen stimulation of growth of the epithelial cells.  相似文献   

14.
The growth of isolated epithelial and stromal cells from both androgen-dependent normal rat prostate and an androgen-responsive model rat prostate tumor is androgen-independent. When added to co-cultures of epithelial and stromal cells separated by a semipermeable membrane, androgen stimulated epithelial cell growth without an effect on stromal cell growth. Northern blot and nuclease protection analysis of mRNA revealed that stromal cells specifically expressed an androgen-sensitive secreted member of the heparin-binding fibroblast growth factor family [keratinocyte growth factor (KGF)/fibroblast growth factor-7]. KGF was mitogenic for epithelial cells, but not for stromal cells. Epithelial cells expressed specifically a splice variant of the bek receptor gene that specifically binds KGF. Expression of the bek receptor gene in stromal cells was undetectable by Northern blot and nuclease protection analyses. The results suggest that stromal cell-derived KGF has the properties of an andromedin, which mediates the indirect control of epithelial cell proliferation by androgen through a directional stromal-to-epithelial cell paracrine mechanism.  相似文献   

15.
Upon androgen deprivation, Shionogi (SC-115) mouse mammary tumors undergo phenotypic changes enabling their escape from growth dependence on androgens. Even within androgen-responsive cell populations, marked clonal heterogeneity is observed in the trophic effects of androgens. The present study compares several parameters of androgen action between three SC-115 cell clonal subpopulations exhibiting high (clone 107), low (clone S1A2) and no trophic response (clone 415) to androgens. These parameters pertain to (1) kinetics of androgen binding, (2) metabolism of 5alpha-dihydrotestosterone (DHT), 5alpha-androstane-3alpha,17beta-diol (3alpha-diol) and 5alpha-androstane-3beta,17beta-diol (3beta-diol), (3) ornithine decarboxylase (ODC) activity and (4) interleukin-1alpha (IL-1alpha) action on cell proliferation. Only marginal differences in the affinity and abundance of androgen-specific binding sites were detected between the three clones. While clone S1A2 degraded DHT to 3alpha-diol at a much faster rate than the highly androgen-sensitive 107 cells and androgen-insensitive 415 cells, differences in the rates of intracrine conversion of 3alpha-diol and 3beta-diol to DHT did not correlate with the ability of these steroids to stimulate cell proliferation. Induction of ODC activity at the onset of exponential growth was strongly DHT-dependent in 107 cells, whereas this dependence was markedly attenuated in androgen-hyposensitive cells. Unexpectedly, DHT strongly repressed the marked ODC induction resulting from fresh medium addition in 415 cells which show no growth response to androgens. Low IL-1alpha concentrations were mitogenic in all three SC-115 clones. Whereas the mitogenic action of IL-1alpha was completely androgen-dependent in 107 cells, this dependence was relieved in S1A2 cells, which responded to DHT and IL-1alpha in an additive fashion. Thus, clonal heterogeneity in the pattern of steroid metabolism within Shionogi tumors cannot solely account for loss of androgen dependence, which may rather correlate with the constitutive activation of transduction pathways controlling the expression of growth-associated genes (e.g. ODC) by serum growth factors, including IL-1alpha.  相似文献   

16.
6-Methylene progesterone (6MP) is an irreversible in vitro kcat inhibitor of rat prostate 5 alpha-reductase, the enzyme which converts testosterone (T) to dihydrotestosterone (DHT). Treatment of adult rats with 6MP or diethylstilbestrol (DES) decreased the weight of the ventral prostate (VP) by 45%, while castration reduced it by 86%. Histologically, the 6MP-treated VP were indistinguishable from those of controls, while the VP from DES-treated rats showed fibrous stromal hypertrophy as in castrated rats. The prostatic hydroxyproline content, an index of collagen levels, was enhanced by castration or DES, but was not significantly increased by 6MP. Within 2 days of 6MP treatment, the 5 alpha-reductase activity was reduced by 46% and ornithine decarboxylase (ODC) activity was lowered by 27%. During this time the prostatic acid phosphatase activity increased 42% and remained elevated with continued exposure to 6MP up to 13 days. The castration-induced involution of the VP was accompanied by a reduction in serum T and an increase in serum luteinizing hormone (LH). 6MP had no effect on T and LH serum levels but reduced the DHT content within the VP by 64%. Our results indicate that the structure and secretory acid phosphatase activity of the VP are less sensitive to changes in the ratio of T:DHT than is cell proliferation. Thus, the relative amounts of DHT and T within the VP may prove to be more significant than the absolute amount of either androgen in controlling prostate growth or its attendant neoplasms.  相似文献   

17.
In normal prostate, keratinocyte growth factor (KGF), also known as fibroblast growth factor-7 (FGF-7) serves as a paracrine growth factor synthesized in stromal cells that acts on epithelial cells through its receptor, KGFR. KGF and KGFR were found in human cancer epithelial cells as well as stromal cells. Since KGF expressed in epithelial cells of benign prostatic hyperplasia (BPH) and in prostate cancer, it has been suggested that KGF might act as an autocrine factor in BPH and prostate cancer. To investigate the roles of KGF in cancerous stroma, primary cultured human prostate cancer stromal cells (PCSCs) were isolated and evaluated. These PCSCs possessed estrogen receptors and KGFR, but not androgen receptor as determined by RT-PCR and Western blot, respectively. KGF exhibited mitogenic and anti-apoptotic effects that correlated with induction of cyclin-D1, Bcl-2, Bcl-xL and phospho-Akt expression in PCSCs, where treatment with KGF antiserum abolished cell proliferation and anti-apoptotic protein expression. PCSCs exposed to KGF for various time periods resulted in phosphorylation of Akt and subsequent up-regulation of Bcl-2. KGF modulated dynamic protein expression indicated that KGF triggered cell cycle machinery and then activated anti-apoptotic actions in PCSCs. Cell proliferation analysis indicated that tamoxifen or ICI 182,780 reduced cell viability in a dose-dependent manner; however, KGF prevented this inhibition, which further demonstrated KGF triggered anti-apoptotic machinery through activating Bcl-2 and phospho-Akt expression. In summary, KGF has an autocrine effect and serves as a survival factor in primary cultured human prostate cancer stromal cells.  相似文献   

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During implantation, matrix metalloproteinases are believed to play roles in the tissue remodelling that accompanies decidualization in the endometrium and in embryo invasion. The objective of this study was to characterize further the expression of matrix metalloproteinases 2 and 9 in the mouse uterus during early pregnancy and oil-induced decidualization. mRNA encoding matrix metalloproteinase 2 was detected in pregnant uteri and uteri undergoing oil-induced decidualization by northern blot analyses. The steady-state concentrations of mRNA encoding matrix metalloproteinase 2 did not change significantly in implantation compared with inter-implantation areas on days 5-8 of pregnancy but were significantly lower in stimulated compared with non-stimulated uterine horns during artificially induced decidualization. mRNA encoding matrix metalloproteinase 9 was also detected in uteri undergoing oil-induced decidualization but not in pregnant uteri. Its concentration was significantly greater in uterine horns undergoing oil-induced decidualization compared with control horns. Immunoreactive matrix metalloproteinases 2 and 9 were detected in the uterus during early pregnancy and oil-induced decidualization by immunohistochemistry, localized to the endometrial stroma, but the staining progressively became weaker and was absent in areas that had undergone decidualization. By day 8 of pregnancy and 72 h after the induction of decidualization, matrix metalloproteinase 2 and 9 proteins remained mainly in the region of non-decidualized stromal cells adjacent to the myometrium. In implantation segments, they were also localized to the region of the trophoblast giant cells. The second objective of the present study was to determine whether endometrial stromal cells isolated from uteri sensitized for decidualization express matrix metalloproteinases 2 and 9. Northern blot analyses and gelatin zymography showed that these cultured cells expressed matrix metalloproteinase 2 and 9, and that transforming growth factor beta1 significantly increased matrix metalloproteinase 9 expression. The results of the present study further characterize matrix metalloproteinases 2 and 9 expression in the uterus during implantation and artificially induced decidualization.  相似文献   

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