原发性肝癌中MTS1/p16基因缺失的研究

肝癌的发生和发展是多种遗传改变的累积造成的，原发性肝细胞癌（ｈｅｐａｔｉｃｃｅｌｌｕｌａｒｃａｒｃｉｎｏｍａ，ＨＣＣ）的发生、发展与癌基因的激活和抑癌基因的失活有关。ＭＴＳ１／ｐ１６是新发现的多重抑癌基因（ｍｕｌｔｉｐｌｅｔｕｍｏｕｒｓｕｐｐｒｅｓｓｏｒ，ＭＴＳ１）现已证实，ＭＴＳ１／ｐ１６在人类多种恶性肿瘤中存在着不同形式的改变［１，２］。我们采用差别聚合酶链反应技术分析了３４例原发性肝细胞癌组织、癌旁组织和１０例肝炎后肝硬变肝组织的ＭＴＳ１／ｐ１６外显子２的缺失，以便了解ＭＴＳ１／ｐ１６基因…     

肝细胞癌p53基因与p21WAF1／CIP1基因的相关性分析

近年来，癌基因、抑癌基因在肿瘤发生发展中的作用日益受到人们的关注，不少学者进行了ｐ５３基因与肝细胞肝癌（ＨＣＣ）发生的相关性研究。有作者报道，野生型ｐ５３基因抑制细胞增殖的功能是通过ｐ２１ＷＡＦ１／ＣＩＰ１基因介导的〔１〕。本文检测７２例ＨＣＣ组织中...     

青年人大肠癌细胞p53蛋白表达和DNA的定量研究

目的：研究青年人大肠癌抑癌基因ｐ５３蛋白的表达和细胞ＤＮＡ含量。方法：采用流式细胞光度术（ＦＣＭ）。结果：青年组大肠癌细胞ＤＩ值（１．３０±０．１７）显著大于老年癌组（１．１０±０．０９）（Ｐ＜０．０１），且细胞增殖指数（ＰＩ）亦明显大于后者（２４．９％±６．５％ｖｓ２０．２％±４．７％）（Ｐ＜０．０５）。青年组大肠癌中ＤＮＡ异倍体癌发生率为８７．１％（２７／３１），而老年癌组仅为２８．６％（４／１４），两者之间差别有高度显著性（Ｐ＜０．００１）。ｐ５３蛋白表达量青年患者（ＦＩ＝１．３４±０．２６）显著大于老年患者（ＦＩ＝１．１５±０．２５）（Ｐ＜０．０１）。在青年大肠癌中，粘液癌和侵犯周围软组织者，其ｐ５３蛋白的阳性表达率（１００％，９５％）分别高于腺癌和浸润较浅者（６７％，５８％）（Ｐ＜０．０５），而且低分化癌和有局部淋巴转移者ｐ５３蛋白的表达阳性率（９３％，１００％）也较高、中分化癌和无局部淋巴结转移者（６９％，６８％）为高。结论：在ＤＮＡ水平上，青年大肠癌的恶性程度高于老年大肠癌；ｐ５３蛋白的高表达可能是造成青年大肠癌恶性度高的原因之一。     

c─erbB─2、ras p21及p53在大肠癌表达的免疫组化研究

对４８例大肠癌连续切片进行ｃ─ｅｒｂＢ─２、ｒａｓｐ２１及ｐ５３３种癌相关基因产物的免疫组化ＡＢＣ法及ＡＰＡＡＰ－ＩＧＳＳ双重标记研究，结果表明：（１）癌相关基因ｃ─ｅｒｂＢ─２、ｒａｓｐ２１和ｐ５３阳性表达率在癌组织分别为５０．２％（２５／４８）、４３．８％（２１／４８）和５４．２％（２６／４８）；癌旁粘膜分别为２５％（１２／４８）、１８．８（９／４８）和２０．８％（１０／４８）；而在＂正常＂结肠粘膜则分别为１２．５％（６／４８）、６．３％（３／４８）和０．（２）有２种以上癌相关基因产物同时表达者在癌组织中有２６例（５４．２％）．在癌旁粘膜有５例（１０．５％），而在正常粘膜则未见有２种癌相关基因同时表达，（３）癌组织中ｃ─ｅｒｂＢ─２＋ｐ２１、ｃ─ｅｒｂＢ─２＋ｐ５３、ｐ２１＋ｐ５３及ｃ─ｅｒｂＢ─２＋ｐ２１＋ｐ５３同时表达者分别为２．１％、１２．５％、１６．７％及２２．９％，（４）ＡＰＡＡＰ－ＩＧＳＳ双重免疫标记结果表明，单一癌细胞可同时表达２种癌基因产物。上述结果提示：ｃ─ｅｒｂＢ─２、ｒａｓｐ２１及ｐ５３可能与大肠病的发生有关，三者在大肠病的发生中可能起协同作用。     

p16和p15基因缺失与造血系统恶性疾病

ｐ１６／ｐ１５基因为定位于染色体ｑｐ２１的抑癌因子，通过抑制细胞周期调节蛋白（ＣＹＣ）和细胞周期蛋白依赖性激酶Ｃ（ＣＤＫ）复合物的形成与激活，阻止细胞由Ｇ１期进入Ｓ期，从而减少细胞的异常生长及变异，防止肿瘤的发生和发展。ｐ１６／ｐ１５基因缺失与造血系统恶性疾病密切相关。肿瘤抑制基因ｐ１５，ｐ１６的发现，为基因治疗血液系统恶性肿瘤提供了新的途径。     

p-MAPK、cyclinD1和p53蛋白在大肠癌中的表达及其相关性

目的：检测ｐ－ＭＡＰＫ、ｃｙｃｌｉｎＤ１和ｐ５３蛋白在大肠癌中的表达，并探讨其相关性。方法：免疫组织化学Ｓ－Ｐ法。结果：１４０例大肠癌中ｐ－ＭＡＰＫ、ｃｙｃｌｉｎＤ１和ｐ５３蛋白的阳性表达率分别为９２．９％（１３０／１４０）、８７．１％（１２２／１４０）和６６．４％（９３／１４０）；５０例相应癌旁肠粘膜中阳性表达率分别为４．０％（２／５０）、６．０％（３／５０）和２．０％（１／５０）。三者阳性表达     

癌基因MDM_2和抑癌基因p53在肉瘤组织中的变化及其相关性

目的：研究ＭＤＭ２癌基因和ｐ５３抑癌基因在人肉瘤发生中的作用。方法：应用分子杂交和免疫组化技术检测了５０例肉瘤组织、１３例良性间叶瘤和１０例癌组织中ＭＤＭ２及ｐ５３的分子改变。结果：ｐ５３过表达率在肉瘤为２４／５０（４８％）；ＭＤＭ２扩增和过表达在肉瘤为１９／４９（３８．８％）和２７／４９（５５％），而在良性间叶瘤分别为１／１３（７．７％）和１／１２（８．３％），癌组均为１／１０（１０％）；ＭＤＭ２基因的异常在不同类型肉瘤间存在差异性；ＭＤＭ２扩增和过表达间存在不一致性：１９例扩增中１６例有过表达，而１１例过表达者无基因扩增。两基因改变的相关分析发现，２４例ｐ５３阳性中１８例有ＭＤＭ２改变。结论：ＭＤＭ２癌基因异常与间叶性肿瘤的恶性表型高度相关，并有一定类型特异性；ＭＤＭ２与ｐ５３的改变在肉瘤的发生中密切相关     

人恶性肿瘤中染色体9p21—p22区带的杂合性丢失

人类恶性肿瘤中常发生染色体杂合性丢失,从而丢失抑癌基因的某一个等位基因。人类９号染色体特别是该染色体的９ｐ２１－ｐ２２区带,在多种肿瘤中都存在着染色体和杂合性丢失。在定位克隆抑癌基因的过程中,对肿瘤中高频率染色体杂合性丢失的分析是对抑部基因进行定位并最终发现和克隆该类基因的先决条件之一。     

乳癌组织端粒酶活性表达及其与p16基因的关系

目的：探讨乳房恶性肿瘤组织中端粒酶活性的表达情况及ｐ１６抑癌基因的影响。方法：应用端粒重复放大程序－酶标法（ＴＲＡＰ－ＥＬＩＳＡ）及ＴＲＡＰ－银染法检测３５例有乳癌组织及２４例良性肿瘤组织中的端粒酶活性,并采用多重ＰＣＲ技术对乳癌组织的ｐ１６基因的缺失空谈进行了分析,结果：３５例乳癌标本中有２８例端粒酶活性表达为阳性（８０％）,而２４例乳房良性肿瘤标本中仅１例端粒酶活性表达阳性（４．１％）。此外３５例乳癌标本中的１５例存在有ｐ１６基因的外显子２及外显子１的缺失（４２．８％）,而该１５例中有１４例被检测为端粒酶活性阳性（９３．３％）,但２０例未缺失标本的端粒酶阳怀率仅为７０％（１４／２０）。结论：端粒酶活性与乳房肿瘤组织的恶性程度密切相关,提示端粒酶参与了肿瘤的形成过程,而端粒酶活性的增高与ｐ１６抑癌基因的缺失突     

nm23-H1、p53、PCNA表达与大肠癌浸润转移的关系

目的：研究大肠癌中ｎｍ２３－Ｈ１、ｐ５３、ＰＣＮＡ的表达与浸润转移的关系。方法：应用ＬＳＡＢ免疫组织化学方法检测７４例大肠癌中ｎｍ２３－Ｈ１、ｐ５３、ＰＣＮＡ和Ⅳ型原的表达。结果：大肠癌中ｎｍ２３－Ｈ１、ｐ５３和ＰＣＮＡ的阳性率分别为７１．６％、５２．７％和８１．１％。大肠癌中ｎｍ２３－Ｈ１低表达与淋巴结转移有关（Ｐ＜０．０２５），ｎｍ２３－Ｈ１的表达在Ⅳ型胶原表达不同的肠癌中无明显差异（Ｐ＞０．０５）；ｐ５３和ＰＣＮＡ过表达与浸润程度和淋巴结转移有关（Ｐ＜０．０５），ｐ５３和ＰＣＮＡ的表达在Ⅳ型胶原表达不同的肠癌中有非常显著的差异（Ｐ＜０．００５）；大肠癌中ｐ５３过表达与ｎｍ２３－Ｈ１低表达有关（Ｐ＜０．０１）。结论：实验结果揭示ｐ５３基因突变对于ｎｍ２３－Ｈ１基因的失活有一定影响，其作用机制有待深入研究。ｎｍ２３－Ｈ１低表达可能仅在大肠癌转移过程中发挥作用，ｐ５３过表达可在大肠癌浸润转移过程及细胞增殖中起重要作用。     

Preferentially deleted chromosome region 9p21 in large hepatocellular carcinomas

The role of somatic deletions in chromosome 9 and chromosome 22 loci in hepatocellular carcinomas (HCC) was studied. Twenty-one paired HCC and adjacent tumor-free liver tissue samples were examined for loss of heterozygosity at six chromosome 9 and ten chromosome 22 loci. Among informative cases, the highest LOH rates were observed at 9p21 (40% or 4/10 at IFNA) and 9q23 (23% or 3/13 at D9S318). Our observed LOH rate at 9p21 was significantly higher than the background level previously reported for the same tumor type. Clinical data indicate that chromosome 9p21 deletions occurred preferentially in larger tumors (>5 cm diameter). However, a sequence analysis of the MTS1 gene coding region in cases of 9p21 LOH did not reveal any change, suggesting another tumor suppressor gene as the LOH target.     

原发性肝细胞癌1号染色体杂合子丢失的初步研究

目的 分析原发性肝细胞癌（ＨＣＣ）１号染色体短臂（１ｐ）上１０个位点等位基因杂合子丢失（ＬＯＨ）,以期寻找１ｐ上可能存在的与ＨＣＣ发生有关的肿瘤抑制基因的缺失区域。方法 用聚合酶链反应（ＰＣＲ）方法分析３８例ＨＣＣ的１号染色体短臂１０个位点微卫星多态性标记的ＬＯＨ。所有患者均做ＨＢＶ５项检测和ＨＣＶ血清抗体的ＥＬＩＳＡ法检测。结果 在８４．２％（３２／３８例）的ＨＣＣ组织中检出染色体１ｐ片段的ＬＯ     

A 3-Mb physical map of the chromosome region 8p21.3-p22, including a 600-kb region commonly deleted in human hepatocellular carcinoma,colorectal cancer,and non-small cell lung cancer

To isolate a putative tumor suppressor gene(s), we have constructed a physical map and a detailed deletion map of chromosome region 8p21.3-p22, where loss of heterozygosity (LOH) has been frequently seen in human hepatocellular carcinomas (HCC), colorectal cancers (CRC), and non-small cell lung cancers (NSCLC). The smallest commonly deleted region at 8p21.3-p22 in HCC and CRC was between the loci defined by CI8-245 and CI8-2644; in NSCLC, a region between CI8-1051 and CI8-2644 was commonly deleted. A contiguous physical map of 12 cosmid markers in the 8p21.3-p22 region was constructed by means of multi-color fluorescence in situ hybridization (FISH) and pulsed-field gel electrophoresis (PFGE). On the basis of this physical map, which spans roughly 3.1 Mb, the estimated sizes of the commonly deleted regions were at most 1.2 Mb in HCC and CRC and 0.6 Mb in NSCLC. As four of the 12 physically ordered markers are located within the 0.6 Mb region commonly deleted in all three tumor types, nearly one fourth to one fifth of the target region has already been covered with cosmid inserts. Genes Chrom Cancer 10:7–14 (1994). © 1994 Wiley-Liss, Inc.     

Colon cancer connections. Cancer syndrome meets molecular biology meets histopathology.

Short tandem repeat polymorphism markers on the short arm of chromosome 8 were used to search for loss of heterozygosity (LOH) in colorectal carcinoma and dysplasia complicating ulcerative colitis, in prostatic carcinoma, and in malignant fibrous histiocytoma (MFH). Fifty percent of prostatic carcinomas (13/26), 44% of carcinomas or dysplasias arising in ulcerative colitis (7/16), and 30% (4/12) of MFH cases showed LOH for markers on 8p. Detailed mapping demonstrated variability in the size of the chromosomal region showing LOH; however, the data suggest a common 30-centimorgan region of LOH on chromosome 8p between the LPL locus and pter in colorectal and prostatic cancers. In addition, LOH was observed on 8p in both high-grade and low-grade dysplasia in ulcerative colitis, indicating that LOH on 8p may occur at an early stage of neoplastic development in this disorder. In contrast, MFH cases exhibited LOH for marker D8S87, which has been identified as being near the putative Werner's syndrome locus. These results suggest that a tumor suppressor gene, located on the distal portion of chromosome 8p, exists in common for prostatic and colorectal carcinomas, and a second tumor suppressor gene may exist linked to the Werner's syndrome locus.     

Comparison of alterations of chromosome 17 in carcinoma of the ovary and of the breast

 Breast and ovarian carcinomas share a region of allelic loss on chromosome 17q25, suggesting that these tumours may arise by similar molecular pathways. We analysed paraffin-embedded tissues from 84 sporadic ovarian carcinomas and 42 sporadic infiltrating ductal carcinomas of the breast for abnormalities on chromosome 17. Loss of heterozygosity (LOH) of at least one informative marker on 17q was identified in 49 of 82 (60%) ovarian carcinomas, as against only 6 of 40 (15%) informative breast carcinomas (P<0.0001). In ovarian carcinoma, LOH was most commonly observed for GH on 17q23 (56%), and was also frequently observed at 17q21 (46%). In contrast, LOH of D17S1330/CTT16 on 17q25 was observed in only 19% of ovarian tumours. LOH in breast carcinomas was most frequently observed at 17q21 (16%), less frequently at 17q23 (7%) and not identified at all at 17q25 in any breast cancers. Immunohistochemical analysis demonstrated overexpression of the p53 gene product in 38 of 84 (45%) ovarian carcinomas, as against 10 of 42 (24%) breast carcinomas (P=0.0195). p53 immunoreactivity was significantly associated with LOH in ovarian and breast cancers. Immunohistochemical expression of HER2/neu was observed in 6 of 84 (7%) ovarian and 3 of 42 (7%) breast carcinomas. There was no relationship between HER2/neu immunoreactivity and LOH. Although sporadic carcinomas of breast and ovary share some regions of allelic loss on chromosome 17q, differences in other alterations on this chromosome suggest divergent pathways of tumour development. Received: 8 July 1998 / Accepted: 6 January 1999     

Allelic loss on chromosomes 3p, 5q and 17p in renal cell carcinomas

Lossof-heterozygosity (LOH) has been studied on 3p (von Hippel-Lindau gene locus), 5q and 17p (p53 gene locus) by a polymerase chain reaction (PCR)-based strategy in 42 sporadic renal cell carcinomas (RCC). LOH at seven micro-satellite loci on 5q was Investigated because a tumor sup presser gene on 5q involved In the development and/or progression of RCC has not yet been identified. LOH was found In seven (17%) RCC at single or multiple locl on 5q, 38% (11/29 Informative cases) on 3p, and 6% (2/35 Informative cases) on 17p. Replication error (RER) was present in 10% (4/42) RCC at single or multiple loci. The minimum region of deletion on 5q to account for LOH was mapped to 5q31.1 (interferon regulatory factor-1; IRF-1 locus), where LOH was detected In 23% (6/26 Informative cases). LOH on 3p and 5q occurred In both stage 2 and more advanced (stage 3 and 4) tumors at similar incidences (41 and 33% on 3p; and 24 and 22% on 5q, respectively), suggesting that LOH on these chromosomes Is an early genetic event. All RCC exhibiting LOH on 3p or 5q (IRF-1 locus) were the clear cell or the mixed clear and granular cell types. These findings suggest that LOH on 3p and 5q plays an important role in the genesis of clear cell RCC. In addition, only one tumor exhibited LOH on both 3p and 5q, which suggests that LOH occurs not sequentially but independently.     

甲状腺肿瘤3号染色体短臂杂合性缺失的研究

目的 探讨甲状腺肿瘤中3号染色体短臂(3p)杂合性缺失(LOH)状态及其临床意义.方法 收集74例甲状腺肿瘤标本,包括20例甲状腺腺瘤(FA)、24例滤泡性甲状腺癌(FTC)和30例乳头状甲状腺癌(Prc).通过PCR扩增和银染分析其3p上11个微卫星位点的杂合性缺失状态.结果 FFC的LOH频率达到71%(17/24),PTC中30%(9/30),FA中10%(2/20).FFC的3p LOH频率显著高于FA和PTC(P<0.01).FTC中存在两个最小共同缺失区,分别位于3p26-pter和3p14.2-3p22.PTC上存在一个最小共同缺失区,位于3p 25.2-26.1.结论 FTC的3p LOH频率显著高于FA和PTC.3p的3个最小缺失区上可能存在着与FTC和PTC发生发展相关的肿瘤抑制基因.     

中国人结肠癌染色体12p12-13杂合性丢失的研究

目的通过对中国人结肠癌染色体12p12-13杂合性丢失（loss of heterozygosity,LDH）分析，了解KRAS2基因与结肠癌发生发展的关系。方法从10例结肠癌手术切除标本中，提取肿瘤、癌旁及相应正常组织的DNA，用PCR．变性聚丙烯酰胺凝胶电泳．免疫荧光标记多重微卫星PCR法，对染色体12p12-13杂合性丢失进行分析。结果10例癌旁组织中有3例（30％）在12p12-13处至少有一个位点出现杂合性丢失，其中D12S1034出现频率最高，为28．57％（2／7）；10例原发性结肠癌标本中6例（60％）在12p12-13处至少有一个位点出现有杂合性丢失，D12S1034和D12S1591是高频率丢失集中的区域，均占42．86％（3／7）；癌旁组织、癌组织均发生LDH的标本有3例，占30％（3／10）；仅在癌组织中发生LDH的标本有3例，占30％（3／10）；仅在癌旁组织中发生LDH，癌组织无信号的标本1例；杂合性丢失的频率与肿瘤患者的年龄、性别、肿瘤大小、肿瘤部位及淋巴结转移均无关。结论SRAS2基因所在的12p12-13区域在结肠癌发生发展过程中出现基因组不稳定，该区域的高频杂合性丢失可能直接影响野生型KRAS2基因的转录与翻译。     

Rb基因在肝癌组织及细胞中存在缺失

利用ＰＣＲ技术对４２对肝癌及癌旁正肝细胞，４个肝癌细胞株的Ｒｂ基因的两个数量可变的重复序列（ＶＮＴＲ）区进行了分析，发现８例肝癌组织（１９．０２％）和２株肝癌细胞存在Ｒｂ基因的杂合性丧失（ＬＯＨ），表明Ｒｂ基因的缺失在肝癌的发生发展中起着一定，地ＰＣＲ－ＶＮＴＲ技术在快速检测Ｒｂ基因缺失上的价值进行了讨论。     

Genetic Changes in Chromosomes 1p and 17p in Thyroid Cancer Progression

Little is known about the genetic alterations that occur during the progression of thyroid neoplasms. To understand better the biology of thyroid tumors, we investigated several genetic loci in benign and malignant thyroid neoplasms. Forty-one thyroid tumors (6 adenomas, 16 papillary, 14 follicular, and 5 anaplastic carcinomas) were studied. Normal and tumor cells were microdissected from paraffin-embedded tissues. DNA was used for polymerase chain reaction-based loss of heterozygosity (LOH) analysis with the following markers: D1S243 (1p35–36), D1S165 (1p36) and D1S162 (1p32), TP53 (17p13), and INT-2 (11q13). Immunohistochemistry for Ki-67 was performed. The Ki-67 labeling index (LI) was the percentage of positive tumor cells. LOH at 1p was seen in 2 of 5 (40%) informative cases of anaplastic carcinoma (2 of 2 at D1S162 and 1 of 2 at D1S165) and in 2 of 11 (18%) informative cases of follicular carcinoma (2 of 7 at D1S243, 2 of 7 at D1S165, and 1 of 6 at D1S162). One anaplastic (20%) and two follicular carcinomas (14%) had LOH in at least two of the 1p loci analyzed. None of the adenomas and papillary carcinomas had LOH at these loci. LOH at 17p and 11q13 were infrequent. Ki-67 LI was 1.4, 7, 16, and 65% in adenomas, papillary, follicular, and anaplastic carcinomas, respectively. Allelic loss at 1p may occur in aggressive types of thyroid carcinoma and may be a marker of poor prognosis. LOH at 1p may represent a late genetic event in thyroid carcinogenesis. LOH at 17p and 11q13 (MEN gene locus) is uncommon in thyroid neoplasms.