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1.
为了明确N-ras、c-myc癌基因在人肝细胞癌(HCC)中的表达及其形态学分布,我们对38例石蜡包埋的HCC(其中33例带有癌周肝组织)标本进行了原位核酸杂交和免疫组化研究。结果表明,HCC及癌周肝组织中N-ras表达阳性率分别为42%和39%;c-mycmRNA阳性表达率分别为47%和36%;c-myc蛋白阳性率分别为53%和39%。HCC与癌周肝之间N-ras、c-mycmRNA及c-myc蛋白表达水平无显著差别;c-mycmRNA及蛋白阳性强度也无显著差别,其形态学分布基本一致,主要集中于癌细胞和癌周肝中的部分高度增生结节;N-ras表达增强主要见于癌细胞、癌周肝中的高度增生结节、小细胞性不典型增生及少部分肝小多角细胞。它们与HBxAg表达之间无明确的对应关系。上述结果显示,HCC中N-ras、c-myc表达都显著增强,它们可能是人HCC发生中较晚期的事件,而N-ras表达增强早于c-myc癌基因活化。  相似文献   

2.
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   

3.
动脉平滑肌细胞(SMC)是动脉粥样硬化(AS)斑块中的主要细胞,它的增殖在AS形成过程中极其重要。脂蛋白和氧化修饰型脂蛋白对SMC增殖的影响以及SMC增殖与原癌基因异常表达的关系是当前AS发病机制研究的热点之一。我们在建立人主动脉SMC体外培养方法的基础上,观察了LDL,VLDL及HDL和相应的氧化修饰型脂蛋白对培养人SMCfos,myc,erb-B原癌基因转录表达的影响。结果表明:①HDL对SMCfos,myc基因表达无影响;②LDL和VLDL有使这些基因表达增加的趋势,但与对照比较差异不显著(P>0.05);③OX-VLDL,OX-VLDL和OX-HDL有使SMCfos,myc基因表达显著增强的作用(P<0.01),且其作用较相应的天然脂蛋白大(P<0.01).上述结果说明:LDL,VLDL,OX-LDL,OX-VLDL和0X-HDL的致AS作用可能与刺激SMCfos和myc癌基因表达增加有关。  相似文献   

4.
本工作观察了体外环境中不同水平的维生素E和微量元素Se对人肝癌细胞株(SMMC-7721)生长、分化和其癌基因(N-ras、c-myc)表达水平的影响。实验结果表明:高水平维生素E(2.4、9.2、24.0nmol/L)和Se(0.15、0.30、0.60nmol/L)对肝癌细胞的集落形成率具有明显的抑制作用;生化分析显示高水平维生素E和微量元素Se均可明显抑制环境中脂质过氧化的水平,Se对癌细胞甲胎蛋白的分泌有明显的抑制作用,而维生素E作用不明显。细胞原位杂交发现维生素E浓度为2.4和9.2nmo1/L时对细胞癌基因N-ras的表达具有明显抑制作用;Se浓度为0.15和0.30nmol/L时对癌基因c-myc的表达明显抑制。实验还观察了维生素E和Se之间的叠加效应,结果显示除对环境中脂质过氧化的抑制作用具有叠加效果外,对其他指标没有明显作用。  相似文献   

5.
在建立大鼠肾小球系膜细胞(MC)体外培养方法的基础上,通过3H-TdR参入实验,RNA印迹分析和斑点杂交观察bFGF对MCDNA合成及原癌基因c-fos和c-myc表达的影响.结果表明,bFGF作用于MC18h,MC的3H-TdR参入率明显增加(P<0.05),24h达到高峰(P<0.01);bFGF显著诱导原癌基因c-fos和c-myc表达,其表达活性分别于30min和1h达到高峰.提示bFGF是MC的强效丝裂原,其对MCDNA合成的促进作用与诱导原癌基因c-fos和c-myc表达有关.  相似文献   

6.
用免疫组化技术和PCR-SSCP技术对高、中、低分化大肠腺癌、癌旁粘膜、正常粘膜及大肠腺癌型息肉的P21、P53蛋白表达和k-ras基因、P53基因突变进行检测。结果,大肠腺癌P21、P53蛋白表达比大肠腺瘤增多,但增加不显著(P〉0.05),二组均比癌旁粘膜和正常粘膜P21、P53蛋白表达阳性率高(P〈0.01),大肠腺癌k-ras基因和P53基因突变率比大肠腺瘤、癌旁粘膜和正常粘膜组显著增加  相似文献   

7.
动脉平滑肌细胞(SMC)的增殖在动脉粥样硬化(AS)的形成过程中极其重要。我们在建立人主动脉SMC体外培养方法的基础上,观察了LDL,VLDL及HDL和相应的氧化修饰型脂蛋白对培养人SMCsis,jun,H-ras原癌基因及Rb抗癌基因转录表达的影响。结果表明:(1)HDL对SMCsis,jun,ras基因表达无影响;(2)LDL和VLDL有使这些基因表达增加的趋势;(3)ox-LDL,ox-VLDL和ox-HDL具有使SMCsis,jun,和ras基因表达显著增强的作用(P<0.01),且其作用较相应的天然脂蛋白大(P<0.01);(4)天然和氧化修饰型脂蛋白对Rb基因表达均无影响。据上述结果推测:LDL,VLDL,ox-LDL,ox-VLDL和ox-HDL的致AS作用可能与刺激SMCsis,jun和ras原癌基因表达增加有关。  相似文献   

8.
应用免疫组化方法检测ras基因蛋白和表皮生长因子受体(EGFR)在75例胃癌组织中的表达,研究它们与胃癌病理特征及预后关系。75例胃癌ras基因表达阳性率为46.7%,与胃癌的分化程度,生长方式,浸润深度和淋巴转移呈明显正相关(P<0.05);EGFR表达阳性率61.3%,癌旁组织及新生血管有阳性表达;EGFR表达与胃癌大体类型,分化程度,生长方式和淋巴结转移呈正相关(P<0.05);ras蛋白表达与EGFR表达有明显关系(P<0.05);Kaplan-Meier生存分析ras蛋白和EGFR表达与胃癌的预后有明显的关系(P<0.01)。两者表达的检测有助于判断胃癌的恶性程度和预后估计。  相似文献   

9.
应用细胞培养、3H-TdR和3H-Leucine掺入方法,观察血小板生长因子BB(Platelet-derivedGrowthFactorBB)对体外培养兔肺动脉平滑肌细胞DNA和蛋白质合成的影响。结果表明:(1)当PDGF-BB浓度为10ng/ml时,3H-TdR掺入值已较对照组显著增高(6262.5±412.9vs833.5±124.0,P<0.05);当PDGF-BB浓度为20ng/ml时,3H-Leucine掺入值亦较对照线显著增高(10212.8±638.3vs7340.3±1197.9,P<0.05)。(2)PDGF-BB浓度在5-25ng/ml范围内,3H-TdR,3H-Leucine掺入值与剂量直线相关(rDNA=0.97,rprot=0.90P<0.05)。说明PDGF-BB刺激体外培养兔肺动脉平滑肌细胞DNA和蛋白质合成。  相似文献   

10.
蛋白激酶C对鼻咽癌细胞c-myc,c-fos表达的影响   总被引:2,自引:0,他引:2  
用蛋白激酶C(PKC)抑制剂Staurosporine(ST,抑制催化亚基)与Sphingosine(SS,抑制调节亚基)处理人鼻咽癌细胞系CNE-2Z,经点印迹后扫描定量和免疫细胞化学检测c-myc、c-fos表达及其分布。结果发现:(1)c-myc蛋白:主要分布于胞浆,40.7%的细胞核与胞浆均为阳性;经SS或ST处理后,表达明显减弱,且核阳性率分别为17.3%与23.3%。扫描定量在SS组为对照组的60%±25.7%(P<0.05),ST组为对照组的55%±25.9%(P<0.05)。(2)C-fos蛋白:主要分布于胞浆,29.4%的细胞核与胞浆均为阳性,经SS或ST处理后,表达明显减弱,且核阳性率分别为9%与10.2%。扫描定量SS组为对照组的58.6%±25%(P<0.05),ST组为对照组的59.7%±26.2%(P<0.05)。结果表明:使用PKC抑制剂后,两种核癌基因产物量均有不同程度的减少,并且存在细胞内分布的改变,特别是其发挥效应的核内表达明显减少。结合我们以前所发现的PKC抑制剂明显抑制CNE—2Z细胞生长的结果,提示这些癌基因可能参与了PKC对CNE—2Z细胞生长的调节。  相似文献   

11.
作者检测了系统性红斑狼疮(SLE)患者外周血单个核细胞(PBMC)中 C-myc.Ki-ras 和Ha-ras 三种癌蛋白的表达和自然杀伤细胞(NK)亚群状况。结果显示,SLE 患者血液淋巴细胞和单核细胞中上述三种癌蛋白的阳性率均显著高亍健康对照组(P<0.001);而 SLE 组 NK 总数和CD16~+.CD16~+.57~+亚群细胞数则显著低于对照组(P<0.001)。作者结合文献讨论了 SLE 患者PBMC 中癌基因激活的可能机制和重要意义,以及与 NK 细胞和其亚群改变之间的相互关系。  相似文献   

12.
Cellular mediated immune responses in vitro of six males with X-linked lymphoproliferative syndrome (XLP) were investigated. Impaired natural killing (NK) activity compared to seven controls (P less than 0.001) and interferon-alpha activation (P less than 0.011) were detected. However, normal numbers of lymphocytes expressing NK-associated antigens (Leu-7 and MO1) and large granular lymphocytes (LGL) were observed in all patients. Normal lymphocyte-mediated antibody-dependent cellular cytotoxicity (ADCC) (P less than 0.531) was found. NK and ADCC activities have been regarded as being mediated by the same subsets of lymphocytes, however, results of this study do not support this hypothesis: lymphocytes with impaired NK but normal ADCC functions (NK-/K+) were found in males with XLP.  相似文献   

13.
The ability of NK cells to lyse noncultured solid tumor cells was investigated, and the results were compared with lysis of K562. Purified NK cell fractions separated by either Percoll centrifugation or a cell sorter exhibited higher level of lysis against noncultured melanoma cells than did NK-depleted cell fractions. However, the level of lysis was low (less than 10% lysis). Adding recombinant interleukin 2 (rIL 2) to the 4-hr assay induced significant lysis (more than 10%) of noncultured melanoma cells in 18 of 23 (78%) Percoll-enriched NK cell fractions and seven of 11 (64%) sorted Leu-11a+ cells at an E:T ratio of 80 and 10, respectively. In contrast, only two of 13 (14%) PBMC, five of 17 (29%) Percoll-decreased NK cell fractions, and one of 12 (8%) sorted Leu-11a- cells lysed noncultured melanomas in the presence of rIL 2. rIL 2 induced NK cells to lyse noncultured lung and breast cancer cells, as well as melanoma tumors. Exposure of NK cells to 2000 rad radiation abrogated the rIL 2-induced cytotoxicity against noncultured melanomas. Preculture of PBMC for 18 hr with recombinant interferon-gamma (rIFN-gamma) resulted in a modest level of lysis of non-cultured melanomas by sorted Leu-11a+ cells. Adding rIL 2 to the assay increased the cytotoxic activity in both rIFN-gamma-activated Leu-11a+ and Leu-7+ NK subsets. The level of noncultured tumor lysis correlated well with that of K562 lysis in all of the experiments. Purified NK cell fractions in rIL 2 cultures increased cytotoxic activity against noncultured tumor cells with incubation time for up to 3 days, and the level of NK cell-mediated lysis was dependent on both doses of rIL 2 and length of incubation. In contrast, both NK-depleted and sorted Leu-11a- cells demonstrated very low levels of solid tumor lysis after 3-day cultures with a high dose of rIL 2. Killer cell precursors induced by 3-day cultures of sorted cell fractions with rIL 2 and rIFN-gamma were found in both Leu-11a+ and Leu-7+ NK subsets, but not Leu-4+ or Leu-3a+ T lymphocytes. These results indicate that NK cells become cytotoxic for noncultured solid tumor cells by a brief contact with rIL 2, and increase cytotoxic activity after culture with rIL 2.  相似文献   

14.
We have analyzed the peripheral blood lymphocytes from healthy volunteers (20 to 94 years) for the expression of natural killer (NK) cell surface markers, NK activity, and B-cell proliferative response. An increase (2- to 3.5-fold) in relative percentage and absolute number of lymphocytes expressing Leu-7 (HNK-1) or Leu-11a (CD 16) antigen was found in the elderly group (greater than 80 years) as compared to young adults (less than 40 years). A two-color immunofluorescence analysis revealed that the age-associated increment was both progressive and selective; the actual increase occurred in Leu-7+11a+ and Leu-7+11a- populations (subsets with variable and weak NK activity) but not in the Leu-7-11a+ (most active) subset. There is a corresponding decrease in the 7-11a- cells. The ratios of 7+11a+/7-11a+ and 7+11a-/7-11a+ cells doubled with advancing age. Linear regression analysis suggests that the 7-11a+ cells are highly preserved through human senescence and the ratio of 7+11a- cells to the most stable subset, 7-11a+, could expand nearly 100-fold from birth to old age. Further analysis of Leu-7+ cells for the coexpression of Leu-11c (an epitope of Leu-11a) confirmed a similar pattern of changes in 7+11c+ and 7+11c- NK subsets with advancing age. The frequency of Leu-11+ (epitopes 11a+ or 11c+), but not of the subsets of 7+ phenotype (7+11a- or 7+11c-), correlates well with the NK activity (spontaneous killing of K562 tumor cell line). The 7+11c+ cells may directly or indirectly be responsible for the increase in NK activity observed with a majority of aged donors. The inverse relationship observed between the mitogenic response of lymphocytes to pokeweed mitogen (PWM) and the initial frequency of 7+11a-, but not other phenotypes, raises a potential functional significance for the expansion of the 7+11a-(7+11c-) subset. These age-associated NK phenotypic changes provide a cellular basis for our observations on age-associated increase in NK activity and decrease in mitogenic response to PWM.  相似文献   

15.
The effects of repeated bouts of submaximal cycle ergometry exercise on changes in the percentage of peripheral blood T-lymphocytes, the T-helper/inducer and T-cytotoxic/suppressor subsets, and natural killer (NK) cells were studied in 18 healthy young men who had no history of regular exercise training. Subjects were matched on the basis of maximal O2 uptake and assigned randomly to exercise or control groups, with controls resting quietly during the exercise sessions. The percentage of peripheral blood mononuclear leukocytes that reacted with monoclonal antibodies specific for T-lymphocytes (CD3+ cells), the helper/inducer subset (CD4+ cells) and cytotoxic/suppressor subset (CD8+ cells) of T-lymphocytes, and cells with NK activity (Leu7+ cells) were enumerated by fluorescence-activated flow cytometry for samples obtained immediately before and after exercise on days 1, 3, and 5 of a 5-day exercise regimen. The results of this study were mixed with decreases in the percentage of T-lymphocytes before vs. after exercise on days 1 and 3 (P less than 0.001), a decrease in the percentage of T-helper/inducer cells before vs. after exercise on day 3 (P less than 0.05), no effect of exercise on the percentage of T-cytotoxic/suppressor cells, and a marked increase in the percentage of NK cells after exercise on days 1 (P less than 0.05) and 3 (P less than 0.01). The total number of recovered NK cells in the mononuclear leukocyte fraction of blood also increased significantly after exercise on days 1 (P less than 0.05) and 3 (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
Patients with thalassemia who receive multiple blood transfusions are at risk for the acquired immunodeficiency syndrome. Peripheral blood lymphocyte subpopulations were studied in 22 multitransfused thalassemic patients; 10 patients were without splenectomy and 12 were studied after splenectomy. Both groups were negative for anti-HIV. Four additional patients who were found positive for anti-HIV and ten healthy controls were also included in this study. Patients without splenectomy compared to controls and to patients after splenectomy showed a significant decrease of both percentage (p less than 0.001) and absolute numbers (p less than 0.001) of Leu-7+ cells without significant abnormalities of T4/T8 ratio (1.56 +/- 0.4). Patients after splenectomy compared to controls and to patients without splenectomy showed a significant increase of the absolute numbers of lymphocytes and lymphocytes subsets T11+, T3+, T4+, T8+ and SmIg+ cells. In the seropositive patients for HIV only a significant increase of the absolute number of T8+ cells was observed while the T4/T8 ratio was 1.24 +/- 0.73. The decrease in the percentage of Leu-7+ cells in patients without splenectomy correlated inversely to the total amount of blood transfused. In conclusion patients with thalassemia had normal T4/T8 ratio and did not show the abnormal immunologic profile that has been reported in haemophiliacs.  相似文献   

17.
Changes in the lymphocyte subsets of 13 patients with varicella, 5 with hand-foot-and-mouth disease, 4 with scarlet fever, 10 with measles and 20 with Kawasaki disease were examined by immunofluorescent flow cytometric analysis using monoclonal antibodies against lymphocyte cell surface antigens. The results were compared with those of age-matched normal controls. A significant increase in the percentage of Leu-2a positive (Leu-2a+) cells was shown during the early convalescence of varicella, scarlet fever and measles. A significant decrease in the percentage of Leu-3a+ cells during the acute phase was common to all the diseases examined, and a significant decrease of Leu-4+ cells was observed except in measles. As a result, a significant decrease in the Leu-3a+/Leu-2a+ ratio was common to all the diseases examined during the acute and/or early convalescent phases. Leu-M3+ cells increased significantly in varicella, scarlet fever, and Kawasaki disease. HLA-DR+ cells increased significantly in varicella and Kawasaki disease. No significant changes in the proportions of Leu-7+, Leu-10+, and 2H7+ cells were found throughout the course of all the diseases examined.  相似文献   

18.
目的:探讨HIV/HCV重叠感染患者外周血单核细胞亚群与肝损伤的关系。方法:观察对象为HIV/HCV重叠感染患者,分为对照组(n=11)、肝纤维化组(n=12)和肝硬化组(n=7)。运用流式细胞仪检测单核细胞及其亚群变化,瞬时弹性成像(Fibroscan)检测肝纤维化情况。比较单核细胞各亚群在不同程度肝损伤中的差异,并对HIV/HCV重叠感染患者外周血的单核细胞数与肝纤维化情况进行相关性分析。结果:HIV/HCV重叠感染患者肝硬化组与对照组比较,单核细胞CD14low CD16+和CD14high CD16+亚群显著增多(P=0.047,P=0.018)。HIV/HCV重叠感染患者肝纤维化组与对照组比较,单核细胞各亚群差异无统计学意义(P=0.84,P=0.812)。HIV/HCV重叠感染患者CD14high CD16+单核细胞与肝纤维化情况存在正性线性相关,方程成立,并且系数有统计学意义(P=0.018),方程似然比(r 2)0.45。结论:HIV/HCV重叠感染患者CD14high CD16+单核细胞增高有可能是肝损伤加重的原因之一。  相似文献   

19.
The characteristics of the effector cells and monocytes, and conditions required for the monocyte-mediated augmentation of human natural killer (NK) cell activity were investigated. Enriched null cell populations were further fractionated by Percoll centrifugation and used as effector cells. The LGL-enriched fraction was less susceptible than either the unfractionated cells or the other Percoll fractions to the monocyte augmentation when mixed with monocytes in the chromium-release assay and when precultured with monocytes for 12 hr, retrieved by carbonyl iron treatment, and tested for NK activity against K562. This differential susceptibility was reflected at the single cell level. The LGL-enriched Percoll fraction did not display the increase in target-binding cells with lytic activity that was exhibited by the other effector cell preparations after culture with monocytes. No differences in Leu-7 and Leu-11 phenotypes were detected between enriched null cells that had been cultured with and without monocytes for 12 hr. At the monocyte level, it was shown that pretreatment of the monocytes with LPS did not alter their NK-augmenting activity appreciably. Glutaraldehyde-fixed monocytes were not effective, and actinomycin D-treated monocytes were less effective than untreated or irradiated monocytes when mixed with enriched null cells in the assay. Actinomycin D-treated monocytes did not augment and possibly suppressed NK activity tested after 12-hr culture, and irradiated monocytes were less effective for augmenting NK activity than untreated cells. Monocyte-mediated augmentation could be detected when the medium used for null cell-monocyte coculture was supplemented with a) different lots of fetal bovine serum, b) human AB serum, c) autologous serum, or d) no serum. Polymyxin B and indomethacin did not alter the monocyte effect. Finally, the monocyte-mediated augmentation of human NK was not MHC restricted, since allogeneic combinations were also effective. These results suggest that 1) lymphocytes other than LGL participate in the monocyte-mediated augmentation of NK activity, 2) the augmentation is probably activational rather than maturational, 3) the monocytes must be viable to be effective when mixed with null cells during the assay, 4) de novo RNA and/or protein synthesis by the monocytes is required for the monocytes to induce augmented activity in null cells after 12-hr coculture, 5) prostaglandin synthesis and endotoxin are probably not involved in the augmentation, 6) the phenomenon is not MHC restricted, and 7) monocytes may express augmentative and suppressive activities concurrently.  相似文献   

20.
目的检测HIV阴性隐性梅毒患者外周血T淋巴细胞亚群及NK淋巴细胞的比例,并探讨其临床意义.方法应用流式细胞仪检测43例未经治疗的隐性梅毒患者和46例已经数疗程驱梅治疗但RPR持续阳性2年以上的隐性梅毒患者外周血T淋巴细胞亚群及NK淋巴细胞的比例,并与30例健康人群的检测结果相对照.结果1.未经治疗的隐性梅毒患者和已经治疗但RPR持续阳性2年以上的隐性梅毒CD3、CD4及NK淋巴细胞的比例分别与健康人群的检测结果相比,差异均无显著性(P>0.05);未经治疗的隐性梅毒患者CD8淋巴细胞的比例明显高于对照组(P<0.001);已经治疗但RPR持续阳性2年以上的隐性梅毒患者CD8淋巴细胞的比例高于对照组(P<0.05);未经治疗的隐性梅毒患者CD4/CD8的比率明显低于对照组(P<0.001),而已经治疗但RPR持续阳性2年以上的隐性梅毒患者CD4/CD8的比率与对照组相比差异无显著性(P>0.05);2.未经治疗的隐性梅毒患者和已经治疗但RPR持续阳性2年以上的隐性梅毒患者的检测结果相比,CD3、CD4及NK淋巴细胞的比例及CD4/CD8的比率差异无显著性(P>0.05);未经治疗梅毒患者CD8淋巴细胞比例高于已经治疗但RPR持续阳性2年以上的隐性梅毒患者(P<0.05).结论未经治疗的隐性梅毒患者和已经治疗但RPR持续阳性2年以上的隐性梅毒患者均存在细胞免疫不平衡和免疫抑制,这种异常可降低机体抵抗和消除梅毒螺旋体感染的能力,并且可能是梅毒患者难于治愈,RPR持续阳性的主要原因.  相似文献   

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