室管膜瘤染色体DNA失衡的比较基因组杂交研究

目的 探讨室管膜瘤基因组DNA失衡与其组织学类型、分级和部位及患者性别和年龄的关系.方法 用比较基因组杂交检测了16例室管膜瘤的染色体基因组DNA获得和丢失.结果 16例室管膜瘤的基因组DNA获得和丢失检出率分别为15/16和13/16,共发现24个有DNA获得和19个有DNA丢失的染色体区带.黏液乳头状型(WHO Ⅰ级)的获得和丢失区带数均最多,而富于细胞型(WHOⅡ级)和伸长细胞型(WHOⅡ级)的这些异常均多于间变性室管膜瘤(WHOⅢ级).部分获得和丢失区带仅见于黏液乳头状型、富于细胞型、伸长细胞型和间变性中的一种类型,使这些室管膜瘤亚型呈现特征性基因组DNA失衡谱.黏液乳头状型、富于细胞型和伸长细胞型均常出现+7;前两者均有+5,后两者均有-22q;间变性组中+1q 最常见,但无其他亚型常见的+5、+7、-4q、-19q和-22q.任何获得和丢失区带的检出率均无性别差异(P>0.05);≤30岁组和颅内组均以+1q和+7p最常见,>30岁组和脊髓组均以+7最常见,≤30岁组与>30岁组及颅内组与脊髓组比较,三者的检出率差异均有统计学意义(P<0.05).结论 室管膜瘤的基因组DNA失衡频率随其级别升高而相应减少,以上各亚型的特征性基因组DNA失衡谱是决定它们组织学表型和级别的分子遗传学基础,+1q、+5、+7p、+7、-4q、-19q和-22q是评价其生物学行为和患者预后的重要分子遗传学标志.     

髓母细胞瘤比较基因组杂交分析及ERBB-2异常表达的意义

目的研究髓母细胞瘤全基因组的遗传学异常,探讨癌基因的异常表达在髓母细胞瘤发病机制中的作用以及与预后的关系。方法应用比较基因组杂交（comparative genomic hybridization,CGH）技术检测14例髓母细胞瘤全基因组的遗传学改变;同时,在扩大系列的29例髓母细胞瘤中,应用荧光原位杂交（fluorescence in situ hybridization,FISH）和免疫组化染色分别检测ERBB-2在基因水平和蛋白水平的表达。结果（1）CGH结果显示,在所有14例髓母细胞瘤标本中,每一条染色体臂上都检测到了染色体的失衡（获得或丢失）,最常见的染色体异常为17q（85．7％）和7q（35．7％）的获得,以及8p（50％）、16q（28．6％）和17p（35．7％）的丢失;（2）FISH检测中,44．5％（13／29例）的肿瘤细胞有ERBB-2基因的异常表达;（3）免疫组化结果显示,37．9％（11／29例）的病例有抗体c-erbB-2的阳性表达;（4）在预后较差的16例患者中,56％（9／16例）的病例有ERBB-2的过度表达。结论CGH研究发现了髓母细胞瘤全基因组的染色体失衡。在染色体17q特异性位点上ERBB-2基因的异常改变很可能在髓母细胞瘤的发病机制中起着重要的作用,其过度表达与患者的预后密切相关。     

髓母细胞瘤16号染色体的杂合性丢失分析

传统的细胞遗传学显示17号等臂染色体(isochromosome 17q)是髓母细胞瘤最常见的遗传学改变,占该肿瘤的50％～70％。近年来,随着比较基因组杂交(comparative genomic hybl4dization,CGH)技术的应用,人们在髓母细胞瘤整个基因组中发现了更为广泛的遗传学改变。除了17号染色体的异常,染色体的失衡还较常见于10q(41％),11(41％),16q(37％)和8p(33％)。基于这些研究结果,我们试图在染色体16q上进一步寻找与髓母细胞瘤相关的抑癌基因丢失位点。     

髓母细胞瘤8号染色体短臂的杂合性丢失

目的研究髓母细胞瘤8号染色体的遗传学异常,寻找与该肿瘤发病机制有关的杂合性丢失位点。方法通过微卫星分析（microsatellite analysis）方法,应用19个位于8号染色体短臂（8p）上的多态性标记物,检测髓母细胞瘤的杂合性丢失（loss of heterozygosity,LOH）。结果在所检测的23例髓母细胞瘤中,21例为原发肿瘤,2例为复发肿瘤。染色体8p总的LOH比率为51%（124个LOH/243个可分析位点）。我们在8p22-23.2之间发现了一个高比率的共同丢失区,其长度为18.14 cM。结论染色体8p22-23.1上很可能存在重要的抑癌基因,该基因的丢失可能与髓母细胞瘤发病有关。     

髓母细胞瘤全基因组的等位基因型分析

目的研究髓母细胞瘤全基因组的遗传学异常,寻找与该肿瘤发病有关的等位基因失衡的特异性染色体位点。方法应用包括384个微卫星灶标记物的高分辨全基因组等位基因型分析法研究12例髓母细胞瘤的遗传学改变。结果我们在所有39条常染色体臂上发现了238个(62．3％)失衡的等位基因。在染色体7q(58．3％),8p(66．7％),16q(58．3％),17p(58．3％)和17q(66．7％)上存在非随机的等位基因丢失或获得。另外,在平均值以上的等位基因失衡出现在染色体3p(33．3％),3q(33．3％),4q(41．7％),7p(33．3％),8q(41．7％),10q(41．7％),13q(33．3％),14q(33．3％)和20q(33．3％)。染色体上等位基因失衡的比率与患者的预后无明显关联。结论发生在染色体7q,8p,16q,17p和17q上的等位基因失衡可能在髓母细胞瘤的发病机制中起着重要的作用。     

微阵列比较基因组杂交分析一例足月小样儿的染色体畸变

目的 分析一例足月小样儿的染色体畸变,探讨患儿低出生体重的原因.方法 采集临床已确诊的足月小样儿外周血并抽提基因组DNA,进行微阵列比较基因组杂交,分析患儿基因组拷贝数的改变.培养患儿及其父母外周血淋巴细胞,进行染色体核型分析并确定患儿染色体畸变的来源.结果 微阵列比较基因组杂交显示患儿在10q125.2→qter区域存在长22 Mb片段的重复,同时在15q26.2→qter区域存在长5 Mb片段的缺失.核型分析显示患儿核型为46,XY,-15,+der(15)t(10;15)(q25;q26)pat.结论 患儿在10q25.2→qter区域存在部分三体,而在15q26.2→qter区域存在部分单体,这两种染色体畸变可能均是导致患儿表现为足月小样儿的病因之一.     

髓母细胞瘤10号染色体的杂合性丢失分析

目的探讨髓母细胞瘤的遗传学异常及其发病机制。方法通过微卫星分析（microsatellite analysis）方法,应用7个分别位于10号染色体长臂上PTEN（10q23）和DMBT1（10q25）基因位点的特异性标记物,分析18例髓母细胞瘤的杂合性丢失（loss of heterozygosity,LOH）。结果18例髓母细胞瘤中,位于10q23上的LOH比率为24％（9／37可分析标记）;位于10q25上的LOH比率为47％（9／19可分析标记）。结论在髓母细胞瘤中,染色体10q25上高比率的杂合性丢失提示,位于该位点上DMBT1基因的遗传学改变可能在髓母细胞瘤的发病机制中起着重要的作用。     

应用微阵列比较基因组杂交技术精确诊断不平衡染色体畸变

目的 探讨微阵列比较基因组杂交技术(array-based comparative genomic hybridization,array-CGH)在诊断不平衡染色体畸变中的应用价值.方法 选取4例常规G显带染色体核型分析未能确诊的不平衡染色体畸变病例,按照标准的Affymetrix SNP 6.0微阵列的操作手册进行杂交、洗涤及全基因组扫描,并通过相应的计算机软件分析结果.结果 通过array-CGH技术分析,明确了所有4例染色体不平衡畸变的诊断并且进行精确定位,其中对2例患者镜下染色体出现无法确定来源的额外条带进行了自身直接重复的确诊;对2例患者G显带无法识别的缺失合并重复的衍生染色体进行了精确诊断.结论 array-CGH技术在DNA水平上对染色体不平衡畸变的诊断具有独特的高分辨率、高敏感性和高特异性,并且能够精确定位,对染色体疾病作出基因型-表型关系的诊断具有重大的应用价值.     

荧光原位杂交联合微阵列比较基因组杂交分析一例原发性闭经患者的染色体畸变

目的分析1例原发性闭经患者的染色体畸变,探讨该患者原发性闭经的可能原因。方法采集临床已确诊的原发性闭经患者外周血,并抽提基因组DNA,进行荧光原位杂交和微阵列比较基因组杂交,分析染色体异常。结果微阵列比较基因组杂交显示患者染色体Xp22.31区域存在长1.637Mb片段的三倍体,Xp21.2-q21.1区域存在长52.156 Mb片段的重复片段。结论微阵列比较基因组杂交技术可以检测染色体微小畸变,值得临床推广应用。     

用比较基因组杂交技术(CGH)检测肾癌染色体畸变

目的应用比较基因组杂交技术(CGH)分析原发性肾癌肿瘤组织中染色体异常变化,探讨肾癌细胞遗传物质的改变,揭示肾癌发生发展的内在本质及其与临床特征之间的关系。方法采用CGH技术对12例肾癌组织提取的全基因组DNA进行检测,以了解肾癌全基因组的变化。结果CGH技术检测的12例肾癌标本中均有染色体的畸变(扩增和/或缺失),常见的扩增区是1p、4p、5q、7p、9p、16p,常见的缺失区是3q、4q、6q、9q、14q、18q。结论原发性肾癌存在广泛的遗传物质不平衡现象,肾癌细胞染色体扩增和/或缺失可能是肾癌发生发展的基础。     

Chromosome aberrations associated with centrosome defects: a study of comparative genomic hybridization in breast cancer

Centrosome abnormalities occur frequently in various tumors and can cause chromosomal instability and eventually promote cancer development. We investigated the chromosome aberrations associated with centrosome abnormalities in 30 cases of breast cancer, combining immunohistochemical staining and comparative genomic hybridization. Except for some common chromosome alterations (including gains of 1q, 8q, 17q, 20q, and Xq and losses of 8p, 11q, 13q, 14q, 16q, 17p, 22q, and Xp) that have also been seen more frequently in other studies, we discovered some new changes that have rarely been reported, including gains at 2p, 5p, 10p, 15q, 16p, 18q, 21q, and 22q and losses at 6p, 8p23, 11p13-pter, 13q34, and 14q32-qter. We also identified some changes (such as gains of 17q, 20q, and Xq and losses of 17p, 13q, and 14q) harboring candidate genes. We also explored the expression of centrosome protein in different molecular subtypes of breast cancer. Our findings provide a new way to explore the molecular mechanisms of breast tumorigenesis and accordingly potential new targets for therapy for this disease.     

比较基因组杂交技术的应用

肿瘤发生和发育畸形与染色体的不平衡有关,包括染色体的扩增和缺失.常规的比较基因组杂交技术(conventional comparative genomic hybridization)由于能在一次试验中掌握整个基因组DNA拷贝数的变化并可以将此改变准确的定位于染色体,因而在探讨肿瘤的发生和生长发育畸形机理的研究方面得到了广泛的应用.在此基础上发展起来的微阵列比较基因组杂交技术(microarray CGH/ array-based CGH),为精确、定量地研究人类基因组微缺失和微扩增及其定位提供了有力工具.本文综述了CGH和CGHa 技术的原理及应用.     

Minimal regions of chromosomal imbalance in retinoblastoma detected by comparative genomic hybridization

Mutation of both alleles of the retinoblastoma gene (RB1) initiate oncogenesis in developing human retina, but other common genomic alterations are present in the tumors. In order to sublocalize the altered genomic regions, 50 retinoblastoma tumors were examined by comparative genomic hybridization (CGH). The minimal regions most frequent gained were 1q31 (52%), 6p22 (44%), 2p24-p25 (30%) and 13q32-q34 (12%). The minimal region most frequently lost was 16q22 (14%). The overall total number of gains or losses evident on CGH was significantly greater in those tumors with either or both 6p or 1q gain, than in tumors with neither 6p nor 1q gain suggesting that chromosomal instability may be associated with acquisition of these changes. Genes mapping to 6p22 and 1q31 may be important in tumor development in retina subsequent to the loss of RB1 alleles.     

利用比较基因组杂交技术分析食管癌组织中染色体基因组的变化特征

目的　探讨河南食管癌高发区居民食管癌发生发展的基因组变化特征。方法　应用比较基因组杂交技术分析52例原发性食管癌患者染色体基因组变化,按临床分期、有无淋巴结及远处转移进行分组比较。结果　在食管癌中3q、8q、5p、1q、6q、18p、20q的染色体基因组扩增和3p、1p、9q、19p、4p、8p染色体基因组丢失频繁( >20% )。3q、5p、1q、11q13 14的染色体基因组扩增和4pq、13q染色体基因组丢失与食管癌病理分期相关(P<0 .05)。8q扩增和4p丢失与淋巴结转移相关(P<0. 05)。2p扩增和4pq、l1q14 qter的丢失与远处器官转移相关(P<0 .05)。结论　染色体3q、8q、5p、1q、6q、18p和20q部位可能存在与食管癌变密切相关的癌基因, 3p、1p、9q、19p、4p和8p可能存在与食管癌变密切相关的抑癌基因; 3q、5p、1q、11q13 14扩增和4pq、13q丢失与食管癌的发展相关,而8q、2p扩增和4pq、11q14 qter的丢失是食管癌发展的晚期事件与食管癌转移相关,不同的基因参与了淋巴结转移和远处器官转移。     

Chromosome DNA imbalances in human astrocytic tumors: A comparative genomic hybridization study of 63 Chinese patients

Astrocytic tumors are the most frequent primary brain neoplasms. They are clinically characterized by wide variations in histology. Analysis of chromosome DNA imbalance may help to advance diagnosis, grading, and classification, and to determine appropriate therapeutic approaches for tumors of astrocytic lineages. Comparative genomic hybridization (CGH) provides comprehensive information about chromosome DNA aberrations, and is an important technique for evaluating the differences at genomic levels among the same or different grade tumors. In this study, 63 astrocytic tumors of Chinese patients were screened by CGH, and the relationship between their chromosome DNA imbalances and the histopathological classification, grading, and clinical features was analyzed. Most tumors showed genomic copy aberrations detected by CGH. The most frequent abnormalities were regional gains in chromosome 1q and 7p; regional losses in chromosome 1p, 2q, 4q, 6p, 10q, 12q, 15q, 19q, and 22q were also frequently observed. The gain of 1q and the loss of 15q were relevant to the histological types and grades of WHO classification. The losses of 4q and 10q correlated with age in the group of anaplastic astrocytoma, which was unreported in the literature. This study confirmed that chromosomal aberrations, such as +1q, −4q, −10q, +7p, and −15q possibly contributed to the pathogenesis of these tumors. Our data was the first report on the chromosomal aberrations of astrocytic tumors of Chinese patients.     

Detection of chromosomal imbalances in retinoblastoma by matrix-based comparative genomic hybridization

The genetic hallmark of retinoblastoma is mutation or deletion of the RB1 gene, whereas other genetic alterations that are also required are largely unknown. To screen for genomic imbalances on a genomewide level, we studied a series of 17 primary retinoblastomas by matrix-based comparative genomic hybridization (matrix-CGH). The matrix-CGH chip contained 6,000 immobilized genomic DNA fragments covering the human genome, with an average resolution of about 500 kb. The most frequent imbalances detected were gains on chromosome arms 1q (12 of 17), 6p (10 of 17), 2p (5 of 17), and 19q (4 of 17) and loss on 16q (7 of 17). Candidate regions could be narrowed to small intervals by the identified minimally overlapping regions on 1q22, 1q32.1q32.2, 2p24.1, and 6p21.33-p21.31. Furthermore, two as-yet-unknown high-level amplifications were detected, each in a single patient, on chromosome bands 1p34.2 and 1p33. Thus, this study identified new chromosomal regions and therefore potential candidate genes that may play a role in retinoblastoma.     

Detection of chromosomal DNA gains and losses in testicular germ cell tumors by comparative genomic hybridization

To extend the results of conventional cytogenetic analysis of testicular germ cell tumors (TGCTs), we applied the new molecular cytogenetic method of comparative genomic hybridization (CGH), which enables the detection of chromosomal imbalances without the need for dividing cells. DNA from II TGCTs was studied by CGH. In all tumors examined, gain of 12p, mostly of the whole p arm, could be demonstrated. However, in three tumors, an amplification of 12p material restricted to the chromosomal bands 12p11.2-p12.1 was found. Further fluorescence in situ hybridization (FISH) analysis using a yeast artificial chromosome (YAC) that was previously mapped to that region revealed multiple copies of that chromosomal segment in interphase nuclei of these tumors. This finding is an important clue to the localization of candidate protooncogenes at 12p involved in TGCTs. Gains of small chromosomal regions at 2p, 4q, 6p, and 19p were also detected recurrently. Furthermore, gains of chromosomes 8, 14, 21, and X as well as loss of chromosome 13 were frequent findings. In conclusion, CGH provides new insights into genetic alterations of TGCTs. By using CGH, chromosomal subregions could be identified that may harbor genes involved in the pathogenesis of this malignancy. Genes Chromosom Cancer 17:78–87 (1996). © 1996 Wiley-Liss, Inc.