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11.
12.
Comparative genomic hybridization (CGH) analyses have detected gains of copy number on 13q, especially at 13q31-q32, in cell
lines and primary cases of various types of lymphoma. Since amplification of chromosomal DNA is one of the mechanisms that
can activate tumor-associated genes, and because 13q amplification had been reported in various other types of tumors as well,
we attempted to define by fluorescence in situ hybridization (FISH) a common region at 13q31-q32 in which to explore genes
that might be targets for the amplification events. Although the commonly amplified region we defined was relatively large
(approximately 4 Mb), only one true gene, GPC5, was found there. GPC5 was over-expressed in lymphoma cell lines that had shown amplification, in comparison with those that had not. Our findings
suggest that GPC5 is a likely target for amplification, and that over-expression of this gene may contribute to development and/or progression
of lymphomas and other tumors. 相似文献
13.
V. Turinelli T. Marchal F. Ponce C. Bonnefont-Rebeix C. Fournel-Fleury 《Comparative clinical pathology》2005,13(3):109-118
Among 276 canine lymphomas referred to the Haematology–Cytology–Immunology laboratory of the Lyon Veterinary School between 1997 and 2003, there were five aggressive large granular lymphocyte (LGL) malignancies. The five dogs were clinically examined and followed up. Cytological and histological analyses of the liver, spleen, lymph nodes, intestine and bone marrow were performed. The immunophenotype and proliferation index were established. The most significant clinical finding was that of an aggressive clinical course, the presence of hepatomegaly and/or splenomegaly, an abdominal lymphadenopathy, anaemia in four cases and blood and bone-marrow involvement in two cases. The cytological presentation was a diffuse infiltration of atypical, large granular lymphoid cells. Two cases were of the null type (CD3–, CD79a–, CD4–, CD8–), and three were of the T-cell type (CD3+, CD79a–, CD4–, CD8+). The proliferation index was high in all cases, with a median of 54.4%. The histological presentation of the null-type cases was an infiltration of the livers portal triads and the spleens red pulp. The T CD8+ cases showed two different patterns, characterised by infiltration: in the first, of all the intestines layers, the livers portal triads, the spleens red pulp and the lymph nodes and, in the second, infiltration of the livers sinusoids, the spleens red pulp. Although these aggressive LGL lymphomas are still poorly known, they may be compared to three types of human lymphoma: aggressive NK cell lymphoma/leukemia, hepatosplenic T-cell lymphoma and enteropathy-type T-cell lymphoma. 相似文献
14.
We report on a case of a 40-year-old male patient who underwent a gastrectomy because of a biopsy-proven large B-cell lymphoma of the stomach. On surgery, a nodule in the spleen also was noted. Grossly and microscopically, the two lesions were different: the tumor of the stomach appeared white-gray on the cut surface and was a centroblastic variant of diffuse large B-cell lymphoma. Histologically, one perigastric lymph node was involved. Grossly, the splenic nodule was gray-yellow and had a histological appearance of an inflammatory myofibroblastic tumor (IMT). The association between malignant tumor and IMT is rare. In such an association, the latter lesion most often has been reported in the spleen. As EBV may be involved in the genesis of both lymphoma and IMT, we tested both lesions for its presence using in situ hybridization, but the tests were negative. It remains to be verified whether the association between lymphoma and IMT is more than fortuitous. 相似文献
15.
转染survivin反义mRNA对Jurkat淋巴瘤细胞生长和化疗敏感性的影响 总被引:2,自引:0,他引:2
目的 研究转染survivin反义mRNA对Jurkat淋巴瘤细胞生长的影响以及转染后淋巴瘤细胞对化疗药物的敏感性。方法 构建survivin反义mRNA真核表达质粒pcDNA3.1-反义(As)survivin;利用脂质体转染法将其转入高表达survivin mRNA T淋巴母细胞淋巴瘤Jurkat细胞系,用逆转录聚合酶链反应(RT—PCR)、免疫组织化学SP法、Western印迹法检测细胞中survivin表达;用细胞计数、流式细胞术(FCM)检测其细胞生长曲线、细胞凋亡指数,并进行光镜、电镜形态学观察;并对转染pcDNA3.1-Assurvivin前后Jurkat细胞分别加入4-羟基-环磷酰胺(CTX)、甲氨蝶呤(MTX)72h后,常规MTT检测细胞存活率。结果 RT—PCR检测转染pcDNA3.1-Assurvivin后48h、5和6周Jurkat细胞survivin mRNA表达,发现survivin mRNA表达皆低于对照组;转染后survivin蛋白表达也明显降低。转染pcDNA3.1-Assurvivin后Jurkat细胞生长倍增时间(52h)明显延长;用FCM检测细胞凋亡发现,转染pcDNA3.1-Assurvivin后Jurkat细胞凋亡指数[20.2%(48h)]明显高于对照组(转染空质粒和未转染组,2.1%和1.3%);5和6周为6.2%和6.8%,明显高于未转染细胞(1.3%和1.0%)。光镜、电镜观察见转染细胞出现较多凋亡细胞及一些变性肿胀细胞;MTT检测结果显示Jurkat细胞转染前后,经化疗药物4-羟基-环磷酰胺和甲氨蝶呤作用,转染细胞的抑制率明显大于未转染组,差异有统计学意义(P〈0.05)。结论 survivin基因对Jurkat细胞系的生长起着重要的作用,抑制survivin基因表达在T淋巴母细胞淋巴瘤治疗中可能有重要的意义,该基因似可能作为治疗的靶点。 相似文献
16.
B细胞特异性激活蛋白Pax-5在淋巴瘤组织中的表达 总被引:2,自引:1,他引:2
目的探讨B细胞特异性激活蛋白(BSAP)/Pax-5在淋巴瘤的表达情况及应用价值。方法按2001年WHO关于淋巴造血组织肿瘤分类标准收集102例弥漫性大B细胞淋巴瘤(DLBCL)、3例滤泡型淋巴瘤(FL)、3例黏膜相关淋巴组织结外边缘区B细胞淋巴瘤(MALT淋巴瘤)、1例结节性淋巴细胞为主型的霍奇金淋巴瘤(NLPHL)、10例间变性大细胞淋巴瘤(ALCL)和10例浆细胞瘤,用免疫组织化学LSAB法同步检测比较BSAP与CD20的表达情况。结果102例DLBCL全部表达CD20,100例表达BSAP,3例FL、3例MALT淋巴瘤和1例NLPHL BSAP和CD20全部阳性表达,10例ALCL、10例浆细胞瘤BSAP和CD20全部阴性表达。BSAP与CD20的表达差异无统计学意义。结论。BSAP/Pax-5是一种新的B细胞标记,阳性信号定位于细胞核,抗BSAP抗体在常规外科病理诊断工作中的应用价值有限。 相似文献
17.
C. Fellbaum J. Sträter M. -L. Hansmann 《Virchows Archiv : an international journal of pathology》1993,423(5):335-341
Extranodal lymphomas of the thyroid (n=19), kidney (n=15) and testis (n=30) were investigated histologically and immunohistochemically for follicular dendritic cell pattern using the monoclonal antibody Ki-FDC1P. This recognizes follicular dendritic cells in paraffin sections. Follicular dendritic cells were most predominant in lymphomas of the thyroid. These thyroid lymphomas showed the morphological features of mucosa-associated lymphoid tissue (MALT) type lymphomas in 18 of 19 cases and were classified as high-grade malignant lymphoma of MALT type with evidence of a low-grade malignant component (n=18). Ten of these cases contained destroyed reactive follicles of follicular dendritic cells. In 6 of these 10 cases follicular dendritic cells occurred in a pattern of tumour-associated abortive follicle type. The remaining lymphoma of the thyroid was an immunoblastic lymphoma of B-cell type showing no detectable follicular dendritic cells. In extranodal lymphomas of non-MALT type follicular dendritic cells occurred in only two cases where immunocytoma involved the kidney. Malignant lymphomas of the kidney (chronic lymphocytic leukaemia,n=2; immunocytoma,n=4; centroblastic lymphoma,n=9) and of the testis (immunocytoma,n=2; centroblastic lymphoma,n=27; immunoblastic lymphoma of B-cell type,n=1) revealed no characteristics of MALT type lymphoma, cytologically or with respect to follicular dendritic cells. Classical lymphoepithelial lesions formed by centrocyte-like cells, a hallmark of MALT, occurred exclusively in thyroid lymphomas of MALT type. Although occurrence of classical lymphoepithelial lesions formed by centrocyte-like cells was limited to thyroid lymphomas of MALT type, a growth pattern of lymphoid blasts, with formation of lesions mimicking lymphoepithelial lesions superficially, was found in 6 of 27 testicular centroblastic lymphomas. Follicular dendritic cells in non-Hodgkin's lymphomas of MALT type show distinct follicular patterns not found in other extranodal lymphomas such as those found in the kidney and testis. 相似文献
18.
caspase-3、bcl-2蛋白在非霍奇金淋巴瘤组织的表达及其与细胞凋亡和增殖的关系 总被引:8,自引:0,他引:8
目的探讨caspase-3、bcl-2蛋白在非霍奇金淋巴瘤(NHL)发生、发展中的可能作用及相互关系.方法应用TdT介导的dUTP缺口末端标记(TUNEL)技术和免疫组织化学链霉素抗生物素-过氧化酶(SP)法,检测5例反应性增生淋巴组织和119例NHL组织中的细胞凋亡和增殖细胞核抗原(PCNA)、caspase-3、bcl-2蛋白的表达水平.结果 caspase-3和bcl-2在119例NHL中表达的阳性率分别为86.6%(103例)和53.8%(64例).二者在良、恶性淋巴组织中的表达方式相反在反应性增生淋巴滤泡中心caspase-3高表达而bcl-2阴性表达,滤泡套区caspase-3阴性表达而bcl-2高表达;在肿瘤性滤泡中心bcl-2常高表达而caspase-3常表达减弱或不表达;在NHL中二者的表达与肿瘤恶性度呈相反关系,高度恶性组中caspase-3的表达(44.4%)高于低度恶性组(23.7%,P<0.01),而B细胞性淋巴瘤中bcl-2的表达(42.6%)低于低度恶性组(75.5%,P<0.01);caspase-3的表达与凋亡指数呈正相关(r=0.512, P <0.01)),bcl-2的表达与凋亡指数呈负相关(r=-0.436, P<0.01).此外,NHL的凋亡指数与增殖指数呈显著正相关(r=0.710, P<0.01).结论 caspase-3可能参与了NHL的凋亡调节机制.caspase-3和bcl-2蛋白在良、恶性淋巴组织中常呈现相反的表达方式,提示二者在淋巴细胞增殖动力学调节中可能存在着密切联系. 相似文献
19.
荷瘤小鼠红细胞免疫功能观察 总被引:15,自引:0,他引:15
本实验利用小鼠可移植性组织细胞型淋巴瘤LⅡ接种于近交系615小鼠右后肢爪垫皮下,按宿主荷瘤时间以及肿瘤生长发展的不同阶段分期分批处死动物,每批动物均从眼房静脉窦取血,检测荷瘤小鼠红细胞C3b受体花环率(RBC-C3bRR),红细胞免疫复合物花环率(RBC-ICR),观察荷瘤动物在肿瘤发展的几个不同时期红细胞免疫功能的变化情况。结果显示,荷瘤小鼠的RBC-C3bRR明显低于正常,并且随着肿瘤的发展呈下降趋势。在肿瘤侵袭早期和中期RBC-C3bRR下降十分迅速,而到肿瘤转移开始至转移晚期以后,其下降速度减慢。荷瘤小鼠的RBC-ICR高于正常,在肿瘤侵袭中期急骤增高,以后稳定在较高水平。本实验结果提示,肿瘤侵袭转移可能与宿主红细胞免疫功能有一定的关系,这些改变可作为评估肿瘤发展程度的参考指标之一,而且对于研究肿瘤转移机理有着十分重要的意义。 相似文献
20.
C. L. Dolman 《Acta neuropathologica》1986,72(2):197-199
Summary Three cases of neoplastic angioendotheliosis were examined immunohistochemically by the peroxidase-antiperoxidase method for Factor VIII-related antigen and various leukocyte markers. In all three cases, the tumor cells stained positively for common leukocyte antigen. IgM, and kappa or lambda light chains were demonstrable in two cases. Stains for carcino-embryonic antigen and muramidase were negative. This indicates that the neoplastic cells in the lumen of blood vessels were of lymphoid origin.Supported by a B. C. Medical Services Grant, Vancouver Foundation 相似文献