Sequential bcl-2 and c-myc oncogene rearrangements associated with the clinical transformation of non-Hodgkin''s lymphoma.

We report a case of untreated non-Hodgkin's lymphoma with histologic progression over 1 yr from a low-grade, small cleaved follicular center cell lymphoma to a high-grade, small noncleaved follicular center cell lymphoma. Both lymphomas had identical immunoglobulin (Ig) heavy-chain joining gene (JH), kappa light-chain joining gene, and bcl-2 gene rearrangements, indicating the clonal identity of the two tumors. The Ig heavy chain locus on one chromosome 14 was involved in an initial t(14; 18) translocation as shown by comigrating JH and bcl-2 rearrangements. However, the oncogene c-myc was in the germline configuration in the initial lymphoma but had one allele rearranged near the 3' end of exon I in the high-grade tumor; DNA sequence analysis was consistent with a chromosomal breakpoint at that site. The presence of the c-myc rearrangement in the high-grade tumor suggest a role for c-myc in the clonal evolution of the low-grade tumor into a more aggressive lymphoma. The coexistence of both bcl-2 gene and c-myc oncogene rearrangements in the same tumor is unusual, with only a few cases reported. Furthermore, this case is unique in the direct demonstration of the histologic and clinical progression of a human lymphoma associated with the sequential rearrangement of the bcl-2 gene and the c-myc oncogene.     

弥漫大B细胞淋巴瘤细胞系中bcl-6、lpp和miR-28基因表达的研究

本研究从基因和蛋白水平探讨弥漫大B细胞淋巴瘤（DLBCL）细胞系中Bcl-6、LPP和miR-28表达,及其之间的相互关系。应用Northern blot检测8个DLBCL细胞系（CTB-1、MD901、OC1-LY8、BEVA、RCK8、MD903、HRC57和K231）bcl-6和lpp的mRNA水平,液相杂交法检测miR-28表达,Westem blot检测BCL-6和LPP的蛋白水平。结果显示,bcl-6基因易位类型涉及Ig基因细胞系（Oc1-ly8、MD903、CTB-1和MD901）,其bcl-6 mRNA的表达较强,而在未涉及Ig基因易位的细胞系（HRC57和K231）中未见表达。lpp mRNA在CTB-1细胞系中表达阴性。miR-28在各细胞系中均有表达,表达强度高到低依次为：K231、CTB-1、MD903、HRC57、MD901、RCK8、OC1-LY8和BEVA。BCL-6蛋白在各细胞系表达由强到弱依次为：RCK8、BEVA、MD901、CTB-1、MD903、OC1-LY8、HRC57和K231;而LPP蛋白在K231细胞系中未见表达,余各细胞系表达由强到弱依次为：HRC57、OC1-LY8、BEVA、RCK8、CTB-1、MD901和MD903。各细胞系中bcl-6和lpp mRNA水平与蛋白的表达并不一致,即高mRNA水平并不一定导致蛋白的表达增加。结论：不同DLBCL细胞系具有不同的BCL-6、LPP和miR-8蛋白表达水平,各细胞系中bcl-6和lpp mRNA表达水平与它们表达的蛋白量不平行,有关bcl-6、lpp和miR-28基因在DLBCL发生、发展中的作用机制有待进一步探讨。     

一株伴有t(6;11)(q27;q23)和p53基因异常的人单核细胞白血病细胞系SHI-1的建立及鉴定

目的建立人急性单核细胞白血病(AML—M5b)细胞系并研究其生物学特性。方法从1例AML—M5b患者白血病复发时的骨髓标本分离出单个核细胞，用液体培养法进行培养。采用瑞特染色、电子显微镜、细胞化学染色、流式细胞仪、R显带核型分析、逆转录-聚合酶链反应(RT—PCR)、荧光原位杂交(FISH)、半固体甲基纤维素集落培养、裸小鼠致瘤实验、荧光定量PCR、DNA荧光染色法及支原体肉汤培养法、短串联重复序列(STR)-PCR、p53基因的PCR扩增产物测序、多色FISH(M—FISH)和^3H—TdR掺入实验等方法对SHI-1细胞的生物学特性进行了鉴定、结果建立了1个可持续增殖的人单核细胞白血病细胞系SHI-1；形态学和免疫表型呈现典型的单核系特征；核型分析显示SHI-1细胞系有和患者复发时骨髓细胞完全相同的异常：46，XY，t(6；11)(q27；q23)，del(17)(p11)；RT—PCR检出MLL—AF6融合基因的转录本；FISH俭测结果显示存在6号和11号染色体之间易位、MLL基因的重排和p53基因的缺失；PCR产物测序结果显示1个p53等位基因6号外显子发生点突变ATC→ACC集落培养显示SHI-1细胞具有较强的集落形成能力；皮下接种4只裸小鼠均形成实体肿瘤；荧光定量PCR提示无EB病毒感染；DNA荧光染色法和支原体肉汤培养法术检出支原体；M—FISH证实传代至2003年3月的SHI-1细胞除有t(6；11)、del(17)(p11)外，还有t(7；13)所致的衍生7号染色体、18单体和来自8号染色体的微小体；STR—PCR结果显示SHI-1细胞系确实来自患者原代白血病细胞；IL4-和IL-15可促进SHI-1细胞的增殖，IFN-1、TNFα、IL-2、PDGF和IL-7可抑制SHI-1细胞的增殖。结论SHI-1是1个伴有t(6；11)(q27；q23)和P53基因异常的裸小鼠高致瘤性人单核细胞白血病细胞系，为白血病研究提供了一个新的有价值的工具。     

非霍奇金淋巴瘤bcl-2／IgH基因重排及微小残留病变的检测

探索bcl-2基因重排在非霍奇金淋巴瘤(NHL)的发生及演变中的作用,以bcl-2/IgH重排为克隆标志,建立敏感的检测淋巴瘤微小残留病变的方法。用多聚酶链反应(PCR)检测bcl-2/IgH基因重排,用系列稀释试验检测该方法的灵敏度。经检测9种恶性淋巴瘤细胞系中Su-DHL-4和Su-DHL-6有bcl-2/IgH基因重排,用系列稀释试验检测该方法的灵敏度为1:10~5。29例NHL石蜡包埋的组织标本中,共检出6例有bcl-2基因重排,其中滤泡型NHL(F-NHL)4例(36.4％),弥漫型NHL(D-NHL)2例(18.2％),全部在B细胞性NHL中检出。16例F-NHL患者中,4例外周血和骨髓中同时检出bcl-2(MBR)/IgH基因重排,化疗达CR后依然存在。结论提示,bcl-2基因重排主要与低度恶性的B细胞性淋巴瘤有关,重排方式以bcl-2(MBR)/IgH为主。bcl-2基因重排的检测为对滤泡性淋巴瘤微小残留病变的检测提供了一个快速、敏感、特异的方法,对该疾病的分期、疗效和预后的评估有一定的临床价值。     

Monoclonal lymphocyte proliferation and bcl-2 rearrangement in essential mixed cryoglobulinaemia

Abstract. A patient with essential mixed cryoglobulinaemia (EMC) type II and hepatitis C virus (HCV) infection, in whom immunophenotypic and genotypic studies demonstrated a clonal proliferation of B lymphocytes, is described. Fluorescent in situ hybridization with probes to Ig heavy chain gene and to the oncogene bcl-2 demonstrated a translocation of bcl-2 to the immunoglobulin heavy chain locus on chromosome 14. A sharp rise in the level of the monoclonal IgM was associated with a second genetic aberration [t(8:22) (q24:q11)]. No other clinical evidence of disease progression could be demonstrated. Low grade lymphoproliferative disorder with typical cyto-genetic abnormalities developed on the background of EMC and HCV. Clinical progression was associated with a second genetic abnormality involving the myc oncogene. It is possible that HCV chronic infection may indirectly influence oncogenes associated with lymphoma.     

套细胞淋巴瘤中P53基因的研究进展

套细胞淋巴瘤(mantle cell lymphoma,MCL)是2001年WHO淋巴造血组织肿瘤新分类中的一种独立的B细胞非霍奇金淋巴瘤,几乎所有的MCL都有t(11;14)(q13;q32)易位,此易位使11q13上的BCL-1癌基因(cyclin D1)与14q32上的IgH基因重排,导致cyclin D1过度表达,促进细胞由G1期进入S期而使G1期缩短。MCL临床病程和转归呈异质性,许多临床和实验室特征可影响其预后,其中P53基因的异常与MCL的病程及转归密切相关。本文就P53基因的缺失、突变与MCL的关系,P53异常患者的治疗作一综述。     

Primary hyperparathyroidism caused by parathyroid-targeted overexpression of cyclin D1 in transgenic mice

The relationship between abnormal cell proliferation and aberrant control of hormonal secretion is a fundamental and poorly understood issue in endocrine cell neoplasia. Transgenic mice with parathyroid-targeted overexpression of the cyclin D1 oncogene, modeling a gene rearrangement found in human tumors, were created to determine whether a primary defect in this cell-cycle regulator can cause an abnormal relationship between serum calcium and parathyroid hormone response, as is typical of human primary hyperparathyroidism. We also sought to develop an animal model of hyperparathyroidism and to examine directly cyclin D1's role in parathyroid tumorigenesis. Parathyroid hormone gene regulatory region--cyclin D1 (PTH--cyclin D1) mice not only developed abnormal parathyroid cell proliferation, but also developed chronic biochemical hyperparathyroidism with characteristic abnormalities in bone and, notably, a shift in the relationship between serum calcium and PTH. Thus, this animal model of human primary hyperparathyroidism provides direct experimental evidence that overexpression of the cyclin D1 oncogene can drive excessive parathyroid cell proliferation and that this proliferative defect need not occur solely as a downstream consequence of a defect in parathyroid hormone secretory control by serum calcium, as had been hypothesized. Instead, primary deregulation of cell-growth pathways can cause both the hypercellularity and abnormal control of hormonal secretion that are almost inevitably linked together in this common disorder.     

A human lymphoma cell line with multiple immunoglobulin rearrangements.

The development of a cell culture system efficient in the establishment of lymphoma cell lines has made it possible to dissect basic biological and molecular aspects of lymphoma cells. We have established a lymphoma cell line from a patient with B cell lymphoma. The cell line has a complex karyotype with translocations involving bands 8q24, 14q32, and 18q21. Molecular analysis revealed that the Myc gene was rearranged; we were unable to demonstrate rearrangement of the Bcl-2 gene. Evaluation of the structure of the heavy chain Ig genes revealed that the cell line carried the same rearrangements as the cells from which the cell line was derived. The pattern of rearrangement, however, was unusual in that there were at least four rearranged bands when DNA cut with HindIII was probed with a fragment of the heavy chain joining region. To further characterize the cell line, subclones were derived. Individual subclones had the same pattern of rearrangement as the parent cell line. The results of these studies provide evidence that multiple rearranged Ig genes may be present in a single clone of cells.     

T(11;18)及核bcl-10蛋白在胃肠MALT淋巴瘤中的表达

为了探讨t(11；18)(q21；q21)染色体易位及核bcl-10蛋白在胃肠粘膜相关淋巴组织淋巴瘤(MALT lymphoma)中的表达，用酸性酚氯仿法从石蜡组织中提取RNA；逆转录合成cDNA后用聚合酶链反应(PCR)扩增API2-MALT1融合基因；用免疫组织化学法检测石蜡切片中bcl—10蛋白的表达。结果表明：42例MALT淋巴瘤中，t(11；18)(q21；q21)染色体易位在低度恶性MALT淋巴瘤中的表达为14％，在伴高恶转化型MALT淋巴瘤中的表达为46％，在40例弥漫大B细胞淋巴瘤(diffuse 1arge B cell lymphoma，DLBCL)对照组中没有表达；43例MALT淋巴瘤中bcl-10蛋白在低度恶性MALT淋巴瘤的核表达为61％，在伴高恶转化型MALT淋巴瘤中的核表达为69％。结论：t(11；18)易位可能与高度进展MALT淋巴瘤有一定相关性，但与DLBCL无关;bcl-10蛋白的核表达在恶性程度不同的两组MALT淋巴瘤中无显著性差异，其原因有待进一步研究。     

慢性淋巴细胞白血病bcl-2基因表达与重排的研究

人类恶性肿瘤常伴有非随机性染色体异常,并由于使调控细胞生长的基因表达失控而在肿瘤的发生中发挥十分关键的作用。bcl-2基因由于t(14,18)染色体易位而激活在低恶度的非霍奇金淋巴瘤的发生和演变中的作用已举世公认。类似的重排和非重排引起的bcl-2过度表达也见于慢性淋巴细胞白血病。我们应用免疫组化染色和聚合酶链反应检测了11例慢性淋巴细胞白血病bcl-2基因表达和重排,结果发现所有病例均高度表达Bcl-2蛋白,1例有t(14,18)(q32,q21)染色体易位。结论提示慢性淋巴细胞白血病普遍存在bcl-2基因高表达,bcl-2基因在慢性淋巴细胞白血病的发生和发展中发挥着十分重要的作用。     

Interphase cytogenetics for the detection of the t(11;22)(q24;q12) in small round cell tumors.

Among the small round cell tumors differential diagnosis is particularly difficult for their undifferentiated or primitive character. In this mixed group of tumors, only the primitive neuroectodermal tumors, which include Ewing's sarcoma (ES), show the unique and consistent feature of the (11;22)(q24;q12) translocation, which can therefore be considered a hallmark of these neoplasias. We analyzed four primitive neuroectodermal tumor cell lines, one osteosarcoma cell line, and 11 patients by fluorescent in situ hybridization with cosmid clones 23.2 and 5.8, bracketing the t(11;22) at 11q24. Metaphase spreads from tumor cell lines, and from biopsy specimens of three patients with ES were analyzed. In the remaining eight patients comprising five ES, two small cell osteosarcomas and one chronic osteomyelitis, only nuclei preparations were available for analysis. We detected the t(11;22) in interphase nuclei of the four primitive neuroectodermal tumor cell lines, of three patients in which the karyotype demonstrated the translocation and in five cases of ES in which cytogenetic analysis had not been possible. Two cases of small cell osteosarcoma and one chronic osteomyelitis were also analyzed and were both normal with respect to the t(11;22). By analyzing cell lines and small round cell tumor samples by fluorescent in situ hybridization, we established that interphase cytogenetics is a rapid alternative to chromosomal analysis for the detection of the t(11;22) and represents an invaluable tool for the differential diagnosis of small round cell tumors.     

The chromosome translocation (11;14)(p13;q11) associated with T cell acute leukemia. Asymmetric diversification of the translocational junctions

The t(11;14)(p13;q13) translocation associated with T cell acute lymphocytic leukemia generates two abnormal chromosomes, designated 11p+ and 14q-. To investigate the mechanism of t(11;14)(p13;q11) formation, we analyzed the translocation junctions of 11p+ and 14q- from two patients. The 11p+ junctions consisted of precise fusions of a pseudo recombination signal from chromosome 11 and the downstream recombination signal of the TCR D delta 2 gene segment from chromosome 14. In contrast, the 14q- junctions from both patients were diversified by random loss and addition of nucleotides at the translocation site. This asymmetric pattern of junctional diversification is typical of normal Ig/TCR gene rearrangement, and therefore implies that the t(11;14)(p13;q11) translocation arose due to aberrant activity of the Ig/TCR recombinase.     

慢性粒细胞白血病急变伴t(3;21)(q26;q22)染色体易位受累基因的研究

目的探讨慢性粒细胞白血病（CML）急性髓系白血病（AML）变伴t（3;21）（q26;q22）的受累基因.方法对1例CML AML变伴t（3;21）（q26;q22）患者细胞间期和中期分裂相细胞采用荧光原位杂交技术（FISH）检测AML1和bcr/abl基因重排,RT-PCR联合序列分析检测t（3;21）（q26;q22）受累基因.结果der（3）和der（21）染色体上均检测到AML1基因杂交信号,AML1-MDS1-Evi1、AML1-MDS1、AML1-EAP及Evi1基因均表达,未见AML1-Evi1融合基因表达,AML1-MDS1-Evi1基因表达水平是AML1-MDS1、AML1-EAP表达水平的1.58和1.54倍,患者Evi1基因表达水平是HEL细胞系Evi1表达水平的2.71倍.结论t（3;21）（q26;q22）导致形成AML1-MDS1-Evi1、AML1-MDS1融合基因及Evi1基因激活,这些继发的分子遗传学异常是CML急性变伴t（3;21）（q26;q22）患者急变发生的分子基础.     

伴有11q异常Burkitt样淋巴瘤19例临床病理分析

目的伴有第11号染色体长臂(11q)异常的Burkitt样淋巴瘤(BLL-11q)是最近新报道的罕见肿瘤,目前病例报道以西方人群为主,鲜有亚洲人群病例资料。本研究旨在探讨中国BLL-11q的临床病理特征及预后。方法收集2016-08—2020-04北京友谊医院病理科诊断的19例BLL-11q,对其病变行HE染色、免疫组化染色、EBER原位杂交和FISH检测,进行随访和文献复习;同时与75例Burkitt淋巴瘤(BL)病例的免疫表型进行对比研究。结果19例BLL-11q患者中男女比为13∶6,中位年龄11岁;8例以头颈部无痛性淋巴结肿大为主要表现,11例发生于淋巴结外,表现为鼻咽部异物感5例,腹痛和咽痛各2例,乳腺肿痛和肩胛骨疼痛各1例。形态学几乎以弥漫浸润为主,肿瘤细胞形态多样,BL样10例,高级别B细胞淋巴瘤(HGBL)样9例。免疫组化显示肿瘤细胞一致性表达CD20、CD10和Bcl-6,与BL病例的免疫表型对比发现,BLL-11q病例常表达LMO2(57.89%vs 1.33%,P<0.001),不表达CD38(57.89%vs 1.33%,P<0.001)。EBER检测所有病例均为阴性。19例MYC基因断裂均阴性并伴有11q基因异常,其中9例做了Bcl-2和Bcl-6基因断裂检测均为阴性。18例患者行化疗伴或不伴利妥昔单抗治疗,1例患者未行放化疗;除1例哺乳期患者外,所有患者均无病生存。结论BLL-11q是一种罕见、预后较好的生发中心B细胞淋巴瘤,各年龄段均可发病,儿童和青少年更为多见,结外相对高发;形态学表现为BL样和HGBL样;BL样形态的BLL-11q病例出现CD38阴性和LMO2阳性的概率高。     

Silencing Bcl-2 in models of mantle cell lymphoma is associated with decreases in cyclin D1, nuclear factor-kappaB, p53, bax, and p27 levels

Molecular mechanisms responsible for lymphoma resistance to apoptosis often involve the bcl-2 pathway. In this study, we investigated the cell signaling pathways activated in bcl-2-overexpressing human mantle cell lymphoma cell lines (JVM-2 and Z-138) that have been treated with oblimersen, a molecular gene silencing strategy that effectively suppresses bcl-2 in vitro and in vivo. Z-138 cells expressed higher levels of bcl-2 and were more sensitive to the effects of bcl-2 silencing, mediated by oblimersen or bcl-2 small interfering RNA, in vitro. Tumors derived following injection of Z-138 cells were sensitive to oblimersen as judged by decreases in tumor growth rate and decreases in cell proliferation (as measured by Ki-67). Immunohistochemistry and Western blot analysis of oblimersen-treated Z-138 tumors revealed a dose-dependent decrease in bcl-2 levels and an associated increase in the proapoptotic proteins caspase-3 and caspase-9. Silencing bcl-2 in Z-138 xenografts revealed an associated dose-dependent suppression of bax, a decrease in nuclear factor-kappaB and phospho-nuclear factor-kappaB, and transient loss of p53 levels. Coimmunoprecipitation studies suggest that the latter observation is mediated by an association between bcl-2 and phospho-mdm2. Bcl-2 silencing also led to p27 down-regulation and coimmunoprecipitation studies point to a role for bcl-2 in regulation of p27 localization/degradation. Bcl-2 silencing was also correlated with loss of cyclin D1a protein levels but not cyclin D1b levels. Coimmunoprecipitation studies indicate that bcl-2 may mediate its effects on cyclin D1a via interaction with p38 mitogen-activated protein kinase as well as a previously unreported interaction between bcl-2 and cyclin D1a.     

套细胞淋巴瘤发病机制的研究进展

套细胞淋巴瘤(MCL)是一种侵袭性的非霍奇金淋巴瘤(NHL),该病的经典遗传学标志为t(11;14)(q13;q32)移位和细胞周期蛋白(cyclin) D1过表达,以难治和易复发为临床特征,并且总体预后不良.近年,随着对MCL细胞遗传学及分子发病机制研究的不断深入,靶向药物的开发与应用,使得该病的临床疗效有所提高.本文就近年来MCL发病机制中细胞遗传学、信号通路、转录因子、肿瘤微环境等改变的研究最新进展作一综述,旨在为MCL的早期诊断和靶向治疗提供新的方向.     

套层细胞淋巴瘤细胞系中染色体13q31-q32上miR-17-92基因簇的DNA序列研究

为了研究B细胞淋巴瘤的染色体13q31-q32上miR-17-92基因簇的特点,观察B细胞淋巴瘤中miR-17-92基因簇在基因组DNA水平上是否存在改变,及其对miR-17-92基因簇的表达和与淋巴瘤发生关系的影响。应用PCR和DNA序列测定技术检测Rec1、G519和Z138三个套细胞淋巴瘤(mantel cell lymphoma,MCL)细胞系中染色体13q31-q32上miR-17-92基因簇。结果表明,3个MCL细胞系的miR-17-92基因簇DNA序列与正常人的序列比对完全一致。由此可以认为,MCL细胞系中miR-17-92基因簇在DNA序列上没有异常改变,不是miR-17-92基因簇的过度表达原因。