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991.
Expression of Mcl-1 in mantle cell lymphoma is associated with high-grade morphology,a high proliferative state,and p53 overexpression 总被引:8,自引:0,他引:8
Khoury JD Medeiros LJ Rassidakis GZ McDonnell TJ Abruzzo LV Lai R 《The Journal of pathology》2003,199(1):90-97
Mantle cell lymphoma (MCL) is a distinct type of B-cell non-Hodgkin's lymphoma characterized by the t(11;14)(q13;q32) and cyclin D1 overexpression. Defects in apoptosis may contribute to pathogenesis. This study evaluated the expression of the anti-apoptotic protein Mcl-1 in two MCL cell lines and five frozen MCL tumours (four small-cell, one blastoid/large-cell) using western blot analysis. Mcl-1 expression was also assessed in 36 formalin-fixed, paraffin wax-embedded MCL tumours (24 small-cell, 12 blastoid/large-cell) by immunohistochemistry. Western blot analysis revealed the expected 37 kD protein product in both MCL cell lines and in five frozen tumours, with the blastoid case having the highest expression level. Using a cut-off of >10% immunolabelled cells for Mcl-1, it was found that 12 of 36 MCL tumours were positive. Mcl-1-positive tumours had a higher frequency of blastoid/large-cell morphology (8/12 versus 4/24, p = 0.009), p53 overexpression (3/10 versus 1/23, p = 0.04), and higher Ki67 immuno-labelling (p = 0.002). It is concluded that expression of Mcl-1 in MCL is heterogeneous. A relatively high level of Mcl-1 expression correlates with high-grade morphology, a high proliferative state, and p53 overexpression. 相似文献
992.
Bonhagen K Liesenfeld O Stadecker MJ Hutloff A Erb K Coyle AJ Lipp M Kroczek RA Kamradt T 《European journal of immunology》2003,33(2):392-401
T cell activation, differentiation and effector functions depend on signals delivered through the antigen-specific TCR and non-clonal costimulatory receptors on the T cell. Activated T cells express the inducible costimulator (ICOS). We examined the co-expression of ICOS with Th cytokines in mucosal immune responses. ICOS+CD4+ Th cells expressed strikingly different cytokines depending on the type of infection encountered and the cells' anatomical localization. In the Th2-dominated response to Schistosoma mansoni, ICOS expression of CD4+ cells isolated from the liver was strongly associated with the expression of IL-5, IL-10, IL-13, and T1/ST2, but not with the chemokine receptor CXCR5, a pattern consistent with Th2 effector cells. In the secondary lymphatic organs of schistosome-infected mice, ICOS expression was randomly correlated with Th2 effector-cytokines, but positively correlated with CXCR5 expression; a pattern consistent with follicular Th cells. In Th cells isolated from gut or liver of mice infected with Toxoplasma gondii, ICOS expression was positively correlated with IFN-gamma production. Finally, in the severe combined immunodeficiency transfer colitis model, ICOS expression was strongly positively associated with IFN-gamma and IL-2. Thus, ICOS appears to costimulate distinct effector functions in different immune responses, depending on factors such as the nature of the antigen encountered and localization and chronicity of the immune response. 相似文献
993.
Bartkova J Rajpert-De Meyts E Skakkebaek NE Lukas J Bartek J 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(1):252-266
Deregulated cell cycle and defective genome-integrity checkpoints are among the hallmarks of cancer.Here we summarize our recent studies of key components of the GI/S machinery in normal human spermatogenesis, and their abnormalities in testicular germ cell tumours (TGCTs), with special emphasis on carcinoma in situ lesions (CIS). Our combined immunohistochemical and immunoblotting analyses of normal human adult and fetal testes, CIS, seminomas, embryonal carcinomas, and teratomas, revealed an 'unorthodox' spectrum of defects within the so-called RB pathway in TGCTs. The early aberrations included lack of expression of the retinoblastoma tumour suppressor (pRB) and the CDK inhibitor pl9ink4d, and overexpression of cyclin D2. Progression from CIS to invasive TGCTswas associated with loss of another two CDK inhibitors and tumour suppressors: pl6ink4a and pl8ink4c. We also found the lack of pRB and pl9ink4d in fetal gonocytes, the candidate target cell for all types of TGCTs. These findings, together with the status of the Chk2-p53 DNA-integrity checkpoint, are considered in relation to the origin, biology and pathogenesis of TGCTs, and potential implications of the GI/S defects for the curability of these tumours. 相似文献
994.
Prognostic factors in laryngeal carcinoma: the role of apoptosis,p53, proliferation (Ki-67) and angiogenesis 总被引:3,自引:0,他引:3
Teppo H Soini Y Melkko J Koivunen P Alho OP 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(4):451-457
Even though the roles of different known or suggested prognostic factors in laryngeal cancer have been studied in detail, clinical stage at time of diagnosis and anatomic subsite of the tumour remain the only practical predictors of clinical outcome and offer the only guidelines in the planning of treatment. In this study, the relative roles of known demographic and clinical prognostic factors, in addition to four histopathological factors, were evaluated in a sample of 100 laryngeal carcinoma patients with multivariate analysis using the Cox regression model. In addition to advanced stage (stage III-IV) (relative hazard of death (HR) 8.9, p=0.01) and supraglottic disease (HR 5.6, p=0.02), high apoptotic index (HR 11.1, p=0.05) was significantly associated with poor survival. Cell proliferation, p53 and angiogenesis did not significantly affect the prognosis. In the future, high degree of apoptosis could be used to identify patients with poor prognosis in laryngeal cancer. 相似文献
995.
为了解含十字形结构域蛋白-3(JMJD3)对肺癌细胞A549增殖与迁徙的影响,通过JMJD3表达质粒转染A549培养48h后,EDU染色及流式细胞术检测细胞增殖与凋亡,划痕实验检测细胞迁徙,RT-PCR检测p21mR-NA表达。结果显示,JMJD3转染后EDU阳性比例明显高于对照(JMJD3:40.75%±2.07%,对照:20.97%±1.5%,P<0.001);G1期细胞比例降低(JMJD3:47.80%±1.85%,对照:54.60%±0.95%,P=0.005)。转染JM-JD3后p21mRNA表达量为35.89%±3.71%,而对照为91.78%±3.74%,两组p21表达变化明显(P<0.001)。转染JMJD3质粒24h和48h后细胞迁徙距离分别为(0.47±0.27)cm和(0.96±0.40)cm,对照为(0.57±0.22)cm和(1.08±0.33)cm,两组无显著性差异(P>0.05)。JMJD3可促进A549细胞增殖,降低G1期细胞比例并下调p21mRNA表达,但对A549迁徙无明显影响。 相似文献
996.
目的 探讨3种不同玻片厚度的激光共聚焦专用细胞培养皿制备的细胞样品在激光共聚焦显微镜(CLSM)下采集的荧光染色图像差异.方法通过活细胞及固定后细胞荧光染色实验,采用激光共聚焦显微镜观察细胞形态及荧光亮度,检测不同条件下成像的平均荧光强度,考察3种厚度玻片(0.085~0.13、0.13~0.16、0.16~0.19m... 相似文献
997.
BACKGROUND:Mouse pluripotent stem cells are induced to differentiate into insulin-secreting cells that can effectively improve blood glucose levels in diabetic mice.
OBJECTIVE:To detect mRNA and protein levels of insulin-like cell clusters from induced pluripotent stem cells and to investigate the function of insulin-secreting cells in vitro and in vivo.
METHODS:Mouse induced pluripotent stem cells cultured in vitro were induced to differentiate into insulin-secreting cells using combined inducers through three stages. The morphology of endodermal cells, islet-derived progenitor cells and mature islet cells in each stage was observed and relative gene expression levels were detected by PCR. Mature insulin-like cell clusters underwent dithizone staining and functions of insulin released in vitro were observed by ELISA assay. Finally, the insulin-secreting cells were transplanted into the subrenal capsule of diabetic mice, and then blood glucose levels were observed.
RESULTS AND CONCLUSION:The mature spherical insulin-like cell clusters were successfully obtained in vitro, which were in iron red by dithizone staining, and expression of insulin mRNA was determined by PCR. The insulin-like cell clusters could secrete insulin in response to various blood glucose levels by ELISA assay. In addition, after the cells clusters were transplanted into the subrenal capsule of mice with type 1 diabetes, the blood glucose levels were marbedly improved. 相似文献
998.
BACKGROUND:With the depth understanding of mesenchymal stem cells, mesenchymal stem cells are found to exert a prominent effect on immune regulation and anti-inflammation.
OBJECTIVE:To investigate the therapeutic effect of umbilical cord blood stem cell transplantation on endotoxin-induced hypertension in pregnant rats.
METHODS:Twenty-four pregnant Sprague-Dawley rats were randomized into three groups with eight rats in each group: control, model and experimental groups. Endotoxin-induced hypertension models were made in the model and experimental groups. Meanwhile, rats were given intravenous injection of umbilical cord blood stem cell suspension (1 mL) in the experimental groups and the same volume of normal saline in the control and model groups. Therapeutic effects of umbilical cord blood stem cell transplantation were observed through detection of systolic blood pressure, urine protein level, serum white blood cell quantity and Ang II and ET-1 expression.
RESULTS AND CONCLUSION:Compared with the control group, the systolic blood pressure, urine protein level and serum white blood cell quantity of rats were increased significantly in the model group, and over time, endotoxin continuously promoted these parameters in the model group. After cell transplantation, a significant reduction in systolic blood pressure, urine protein level and serum white blood cell quantity of rats was found in the experimental group compared with the model group (P < 0.05). After modeling, the expression levels of Ang II and ET-1 were decreased significantly, while these levels were increased significantly after cell transplantation (P < 0.05). These findings indicate that umbilical cord blood stem cell transplantation may have a certain therapeutic effect on gestational hypertension in rats, which may be realized by regulating the secretion of endothelial injury-related factors. 相似文献
999.
目的 探讨cRGD肽二聚体对B16黑色素瘤细胞的体外抑制作用及其在荷B16黑色素瘤细胞小鼠动物模型体内的分布及显像研究.方法 用MTT法检测不同浓度及作用时间cRGD肽二聚体对B16黑色素瘤细胞体外增殖能力的影响.采用直接标记法标记99 Tcm-c(RGD)2.建立荷B16黑色素瘤株动物模型,待肿瘤体积为1.0 ~ 1.5cm3左右时,分别于30min、1h、2h、3h、4h、5h及6h时,进行荷瘤鼠体内生物分布及动态显像研究.结果 cRGD肽二聚体浓度为500mg/L、作用48h时,对B16黑色素瘤细胞的增殖具有明显的抑制作用.室温下、ρ(SnCl2·2H20)=1 g/L、反应时间为30 min时,99Tcm-c(RGD)2的标记率可达(87.42±3.21)%,标记产物经Sephadex G10分离纯化后放射化学纯度大于95%;静脉注射后30min行小鼠全身SPECT显像,肿瘤部位可见明显显像剂聚集,但肿瘤与周围组织的对比度较低;延迟至6小时肿瘤仍清晰可见,且随时间延迟肿瘤与周围组织的对比度增高,此时肿瘤/血液为2.15±0.24,肿瘤/肌肉为5.07 ±0.03.结论 该结构cRGD肽二聚体对B16黑色素瘤细胞株具有一定的体外抑制作用,且动物体内肿瘤组织摄取率高,显像清晰,证明其可进一步应用于聚合物多肽靶向药物的研发. 相似文献
1000.